Building Technology Program

Cooling with less: Design and simulation of multifunctional building components for a material-efficient, heat-resilient architecture

2025-04-07T08:40:47Z

Cooling with less: Design and simulation of multifunctional building components for a material-efficient, heat-resilient architecture Gascón Alvarez, Eduardo As temperatures rise globally and the demand for housing intensifies, designing affordable buildings for heat resilience and with low carbon emissions becomes crucial. Conventional air conditioning (AC) systems, although often an effective and accessible cooling solution, are energy-intensive and typically fail to consider local climatic and urban contexts. This work alternatively focuses on the opportunity behind designing building components (such as slabs, blocks, roofs, or footings) for multifunctionality, integrating passive strategies and low-energy cooling systems within them in a material-efficient manner. Collapsing multiple functions into a single building component is typically regarded as a strategy that leads to better overall performance and reduced costs compared to implementing each function separately. However, the effectiveness of this strategy in cooling-dominated climates and in the context of the current climate crisis remains underexplored. The dissertation proposes new designs and evaluation methods for three multifunctional building components: multi-hollowed blocks (ceramic blocks with interior air pockets), shaped chilled slabs (shaped concrete slabs with embedded radiant ceiling systems), and integrated heat sinks (thermally activated concrete footings and roofs). Each component is designed to optimize a specific cooling strategy based on its context within the building and intrinsic material properties - thermal mass, radiant cooling, and ground/radiative cooling. Chapter 2 demonstrates how shape-optimized ceramic blocks can double the heat capacity of existing commercial solutions without additional material or reduce their weight by 33% while increasing the heat capacity by 23%. Chapter 3 presents slab geometries that achieve embodied carbon reductions of up to 50% relative to conventional prismatic floors while reducing operational carbon by 12-14%. Chapter 4 finds that buildings in temperate climates with a Floor Area Ratio (FAR) of up to 4.5 can meet 100% of the cooling demand exclusively through heat dissipation systems integrated into the building’s foundations and roof. Methodologically, this research puts together heat transfer theory and analytical models with state-of-the-art shape optimization methods; this effort results in a fast and accurate multi-objective simulation framework tailored for early design stages. This thesis provides, for the first time, validated methods and quantitative results that support the viability of multifunctional building components in cooling-dominated climates, optimizing the shape of walls, blocks, foundations, and roofs to improve their structural and thermal performance simultaneously, reducing their weight and improving buildings’ resilience to heat. From a climate adaptation perspective, this approach ensures that buildings are ready for extreme heat even when active systems are unavailable due to, for example, a power outage. From a carbon mitigation perspective, the presented results highlight the potential to reduce the whole-life carbon of buildings by shape-optimizing components for enhanced thermal performance and material efficiency.

Accelerating Urban Building Energy Modeling

2024-12-12T03:55:43Z

Accelerating Urban Building Energy Modeling Le Hong, Zoe; Wolk, Samuel Enabling data-driven decision-making in the built environment is critical to achieving ambitious and urgent decarbonization goals. In the building sector, urban building energy models (UBEMs) have become a valuable tool for jurisdictions to develop evidence-based retrofitting policies, but dynamically exploring solutions is hampered by the computational expense and organizational overhead of physics-based building energy models. In order to address these challenges, we present a fast, flexible, and comprehensive UBEM methodology which can be used to reduce identified barriers to time-sensitive decision-making in building stock decarbonization spheres. The methodology combines the speed of current data-driven approaches with the flexibility of computationally intensive, but accurate, engineering models. Identifying machine learning methods as a viable approach, we implement convolutional neural networks (CNNs) which embed timeseries from hourly weather data and building schedules; the embeddings are then combined with static building characteristics and projected to monthly heating and cooling loads. The proposed approach allows for programmatic flexibility and robustness to unique hourly weather conditions globally, while contextual abstraction enables geometric independence. A dataset of over 1 million detailed thermodynamics-based simulations was constructed to train and validate the surrogate model. Model results at the individual shoebox, building, and urban scales compare favorably to traditional numerical methods and meet accepted error bounds under national energy simulation standards. Additional validation at the urban- and national-scales are performed using public building simulation datasets. We then demonstrate expanded applications, which leverage the reduced computational cost of the framework to make traditionally infeasible analysis modes tractable and deployable. The methodology presented is intended to be utilized for both very-large-scale systematic analysis and near-real-time interactive explorations. In developing this framework, we aim to provide new mechanisms for key stakeholders in the decarbonization effort to quickly generate actionable insights and engage in iterative discussions to develop evidence-based policy across global building stocks.

From Waste to Structure: A Deep Reinforcement Learning Approach to Circular Design

2024-10-17T03:51:02Z

From Waste to Structure: A Deep Reinforcement Learning Approach to Circular Design Sørensen, Karl-Johan I. The design-to-construction process of buildings predominantly follows a top-down linear workflow, where a design is drawn and subsequently refined to determine the required materials and components. This approach assumes an infinite material supply or the capability to manufacture what is needed for the design. Constructing in this manner is resource-intensive and wasteful, making it incompatible with our global climate goals. One way to significantly reduce our material and environmental footprint is by extending the lifespan of building materials through circular design practices. In this approach, the available materials define the architecture, inverting the process from top-down to bottom-up. This method, known as Inventory-Constrained Design, enables the creation of new buildings using materials sourced from construction and demolition waste streams. These inventories, characterized by their non-standard and uniquely varied elements, are hard to design with due to the enormous quantity of possible combinations of even a few discrete elements. Identifying a feasible design that aligns with the designer's intent and meets functional requirements becomes an overwhelmingly time-consuming task, heavily reliant on manual trial and error. Computational optimization has been implemented to automate the process, but state-of-the-art algorithms still require manually pre-defining a parametric target design-space or take too long to compute when applied to larger problems. This thesis proposes a new method for circular design utilizing Deep Reinforcement Learning (RL) to design structures, requiring only a design gesture and the inventory as input. It works by training an artificial neural network to sequentially assemble a structure from inventory elements, following the gesture while meeting a structural goal. Hence, the design layout directly arises from available inventory. After training, the neural net can be employed instantaneously to design new structures with new inventories without any significant computational expense. To evaluate the effectiveness of the RL method, it is applied to the specific problem of inventory-constrained design of planar roof trusses and demonstrated in a realistic example of assembling a long-span roof from a disassembled transmission tower.

Automated Engineering Design for Reusable Concrete Building Structures

2024-10-17T04:15:35Z

Automated Engineering Design for Reusable Concrete Building Structures Wongsittikan, Pitipat Concrete contributes to 8% of global CO2 emission through reinforced concrete (RC) structural system. Unlike steel and timber structures, RC components are rarely reused due to the inseparable phase between concrete and steel. This results in down cycling of the components into aggregates or landfill material. The Pixelframe structural system [1] was proposed to facilitate the reusability of concrete components by implementing the existing external post-tensioning system in bridge structures and fiber reinforced system to design building beams and columns. This work presents an automated engineering design workflow for Pixelframe, including a engineering mechanics of the system that conforms to ACI 318- 19 [2] and fib Model Code 2010 [3], half-scale tests to verify the preliminary behavior of the system, and a scalable design algorithm for minimum embodied carbon designs. The workflow also uncovers new insights on choosing ranges of concrete strengths based on the element lengths and potential carbon reduction from refining the number of different concrete strengths in a building. This work demonstrates the utilization of existing building systems in the context of reusability and the potential of automated computational structures in aiding the design decisions to facilitate the circular economy of concrete structures.

In Tension: Computational exploration of the design space of tensile network structures

2024-10-17T03:43:06Z

In Tension: Computational exploration of the design space of tensile network structures Burke, Adam T. Cable and rope net structures are lightweight tensile systems and generally cannot resist compression or bending. Tensile network structures are often used to span long distances without intermediate supports and have found applications in art, architecture, and structural engineering due to their physical and visual lightness. However, the design of tensile net structures is generally challenging since their form cannot be arbitrarily defined. Instead a process of form-finding must be used to establish a geometry where all edges of the network carry only tensile forces. Physical models and computational methods can be used for the form-finding of tensile network structures; however the primary challenge in the design process is the adjustment of the network parameters to achieve a specific design. Recent work has shown that automatic differentiation software packages can be used to efficiently design funicular structures (that is, those that work in pure tension or pure compression) with additional designer driven objectives, but these techniques remain largely inaccessible to general designers, architects, and engineers due to the involved process of problem setup and limited interactivity of existing tools. To address this limitation, I introduce a new tool set consisting of two main components, Ariadne and Theseus. These components take advantage of automatic differentiation of objective functions for efficient tensile network simulation and provide a user interface for architects, engineers, and other designers as a plugin for a commonly used 3d modeling software. In this thesis, I outline the structure and features of this tool set, show results of networks optimized with different composable objectives, and show some fabricated examples. Next, I explore the the generation of more complex 3d network topologies through a procedural shape grammar. Finally, I explore the use of differentiable simulation in conjunction with machine learning techniques to optimize the geometry of tensile networks using semantic input and to develop an implicit representation of the space of equal edge length tensed network poses. Together, this new tool set and additional methods enable a more expansive exploration of the design space of tensile networks where design intent and practical constraints are respected.

Developing frameworks for an equitable future: from building decarbonization to generative modeling.

2024-10-17T03:20:49Z

Developing frameworks for an equitable future: from building decarbonization to generative modeling. De Simone, Zoe In this thesis I develop computational frameworks to understand equity under two perspectives: building decarbonization policy and generative modeling. Part 1 - Equitable building decarbonization Buildings significantly contribute to global carbon emissions, necessitating urgent decarbonization to meet 2050 climate targets. The U.S. strives for net-zero emissions by 2050, supported by federal incentives promoting building upgrades. However, financing deep retrofits for all U.S. homes exceeds available public funds. This chapter proposes a model that examines long-term carbon reduction trajectories under various incentive policies, focusing on fairness and equity. Using Oshkosh, WI, as a case study, it explores the philosophical, economic, political, and mathematical dimensions of creating just and effective decarbonization policies that ensure healthy, low-carbon homes for all. Part 2 - Equitable diffusion models Generative Text-to-Image (TTI) models, while capable of producing high-quality images, often replicate training data biases. Traditional fairness views in machine learning, which consider fairness as binary, are challenged. This section introduces DiffusionWorldViewer, a novel framework with a Web UI that enables users to analyze the underlying worldviews of diffusion models and edit model outputs to align with their personal fairness perspectives, thus promoting a diverse understanding of fairness in AI technologies.

Low-Cost Masonry for the Design of Barrel-Vaulted Flooring Systems

2024-10-17T03:09:26Z

Low-Cost Masonry for the Design of Barrel-Vaulted Flooring Systems Haile, Nebyu Samuel The world's population is projected to grow rapidly in urban areas, with a projected 2.5 billion more urban dwellers by 2050 (UN-DESA, 2019). This urban growth will notably concentrate in Less Economically Developed Countries (LEDCs), where 16 of the top 20 most populous cities are anticipated to be situated by 2100 (Hoornweg & Pope, 2017). LEDCs face a critical challenge in meeting the demand for affordable housing due to various factors, notably the high material costs, which can make up to 90% of residential construction expenses (Meikle, 2011). Most multi-story housing in LEDCs relies on reinforced concrete frames with flat slabs. This structurally inefficient system heavily depends on imported cement and steel for many locations. Compounding this issue, in LEDCs, the construction sector contributes significantly to their annual carbon emissions, sometimes doubling the global average and exacerbating the climate crisis (Yokoo et al., 2016). Addressing the pressing need for affordable housing requires alternative, more efficient structural systems that utilize affordable and environmentally conscious materials. This thesis aims to address the challenge of affordable housing by proposing the implementation of unreinforced barrel-vaulted earthen floor systems as an alternative to conventional concrete flat slabs, which are often cost-prohibitive in LEDCs. While existing research predominantly focuses on thin concrete shells for vaulted floors, this study emphasizes earthen vaulted floor systems, utilizing locally available and cost-effective materials. Specifically, it analyzes the maximum spanning capacity of three shallow unreinforced earthen barrel-vaulted floor typologies, examining their associated costs and carbon footprints. Furthermore, the thesis investigates the feasibility of one of these typologies by constructing and evaluating a physical 3m span prototype subjected to international building code loads. The outcomes highlight the structural integrity, cost-effectiveness, and reduced carbon footprint of earthen vaulted floor systems, offering insights into a more environmentally conscious and economically feasible floor system typology for building construction in LEDCs.

System-level design of low-carbon structures

2024-10-17T03:56:32Z

System-level design of low-carbon structures Fang, Demi L. “What is more likely to be associated with a reduction in emissions: switching from concrete to timber, or shortening the spans throughout the building?” While such insights are valuable for mitigating emissions from structural systems during early stages of design, it is difficult to answer these types of questions in current paradigms of performance-driven design. This dissertation makes several original contributions to the system-level design of low-carbon structures. First, a literature-supported network of strategies available to reduce emissions during early-stage structural design is established and evaluated on the bases of literature availability, impact, implementability, and compatibility. Material efficiency and material choice represent two key levers for reducing emissions in structural design, but it is difficult to navigate trade-offs between these strategies at a system level of structural design. Holistic design strategies can help achieve this, but these current paradigms of performance-driven design (e.g. deploying rules of thumb, comparing a few design options, and optimization) are limited in their capacity to inform decision-making towards higher performing designs. There is a particular opportunity to produce these insights using data-driven approaches given the growing quality and quantity of data in the field of low-carbon structural design. In response, this dissertation analyzes both types of data that are available in the field: wild data (measured from the industry) and synthetic data (produced from bottom-up parametric structural models). Data from over 200 fully designed structural systems from a structural engineering firm are analyzed. This analysis is the first to 1) provide empirical evidence for floors and foundations representing the largest opportunities for carbon reductions and 2) evaluate the relationship between structural material quantities and embodied carbon in structural systems (many analyses evaluate the latter without the former). In a field where material choice is a predominant impression for reducing emissions, these new insights importantly affirm the prominent role of material efficiency in reducing a structural system’s emissions. While the design space of wild data includes a diverse variety of projects, leveraging a synthetic dataset computed from a bottom-up parametric model helps produce insights specific to the design problem at hand. The final contribution of this dissertation is to propose a computational framework that leverages synthetic data to empower decision-making in design. The framework addresses two challenges: 1) the challenge of extracting decision-making insights from design data, and 2) the challenge of comparing decision-making across continuous (numerical) and categorical variables, which are typical in most design problems. In this framework, a machine learning model is trained on a provided set of design data to compute gradients across the design space. These gradients are distilled into “influence metrics”, which offer a novel, accessible way to build and supplement intuition on low-carbon design decisions. A few case studies in low-carbon structural design are presented to demonstrate the use of the proposed method with synthetic datasets. By striking a meaningful balance between applying rules of thumb and optimization, the method empowers a paradigm shift from performance-driven design to performance-informed, human-driven design. Key words: embodied carbon of structural systems, design decision-making, low-carbon structural design

Beyond the Bioclimatic Chart: An Automated Simulation-Based Method for Assessing Natural Ventilation and Passive Design Potential

2024-10-17T04:09:36Z

Beyond the Bioclimatic Chart: An Automated Simulation-Based Method for Assessing Natural Ventilation and Passive Design Potential Herb, Svenja Technological advancements in the building industry have significantly transformed climate and comfort control in buildings. This allows for air conditioning in deserts and heating in the Arctic, ensuring occupant comfort. This innovation, however, has contributed to a homogenization in architectural designs globally, from the hot climates of Mumbai to the cold environments of Boston, and moderate settings like London. Such uniformity often overlooks local climatic conditions, resulting in increased energy consumption and elevated greenhouse gas emissions. Climate-responsive design on the other hand creates solutions that leverage local climates—such as through natural ventilation and optimal solar gain management—to reduce energy consumption. Depending on climate and program, the coordinated use of these passive design strategies may or may not lead to indoor thermal comfort conditions without the need for an air-conditioning system. There are two primary approaches to explore the passive design potential of a building during schematic design: Bioclimatic chart and building energy modeling (BEM). The former method is a key feature in building science textbooks and is solely based on widely available local weather data. It provides general design advice without requiring previous knowledge or the need to describe the building program. BEMs facilitate detailed testing of how a building is operated and how the above listed passive design techniques can be combined to obtain the highest possible comfort conditions and energy savings. However, the use of BEM has traditionally been more complex and time-consuming to use as it requires significant knowledge of the underlying building physics and numeric methods to mimic them. This thesis evaluates the bioclimatic chart's accuracy in predicting overheating hours associated with various passive design strategies, through comparison with BEM data. Furthermore, it introduces a new simulation-based approach called “ECOmpass”. ECOmpass automates early-stage design simulations and offers design recommendations for passive strategies with just one click.

How Much Does It Really Cost? A Dynamic Approach to Building Retrofit Costs for Decarbonization Pathways

2024-10-17T03:36:42Z

How Much Does It Really Cost? A Dynamic Approach to Building Retrofit Costs for Decarbonization Pathways Kirkeby, Amanda Carbon emissions are driving the planet out of its delicate Goldilocks balance. Evidence and the call-to-action date back to 1896 with Swedish scientist Svante Arrhenius and his seminal paper that first predicted the effect of carbon dioxide on the global temperatures. With the Intergovernmental Panel on Climate Change (IPCC) goal of global net zero emissions by 2050, the urgency is stronger than ever. An ever-growing number of municipalities are setting pledges to do their part, often without a concrete plan. With buildings accounting for 40% of total global emissions, building retrofits are a key component to these pathways to zero carbon. Urban building energy modeling (UBEM) research efforts have developed physics-based decision-making tools to define city-scale technology pathways to reach climate goals. However, a crucial question in making these pathways actionable has been largely neglected: how much does it really cost? The scarcity of contemporary cost data and methods for cost prediction at the urban scale makes this question difficult, and further questions around equitable incentive programs nearly impossible to answer. This work demonstrates the concept and relevance of implementing a dynamic cost model in the UBEM context. Several cost models are applied to a case study of 13,000 residences in Oshkosh, WI to predict costs for homeowners to retrofit their homes with three different upgrade packages. A willingness to pay analysis is then performed with upfront cost predictions from different models, illustrating the impact a more robust cost model may have in providing more realistic predictions of an upgrade strategy’s techno-economic success. Through its compatibility with existing UBEM frameworks and local input costs, the dynamic building upgrade cost model hosts the potential to further support municipalities in developing economically feasible building retrofit strategies for decarbonization pathways.

Pathways to Net Zero: Financing Strategies For Low-Income Homeowners

2024-10-17T03:48:04Z

Pathways to Net Zero: Financing Strategies For Low-Income Homeowners Moore, Lauren Housing retrofits are crucial for accomplishing national housing sector decarbonization goals. Single measure retrofit improvements are not sufficient for low-income homes which are often in less-thanoptimal condition and are subsequently uncomfortable and expensive to operate. Comprehensive retrofit approaches are necessary to achieve the energy efficiency targets for the aging housing stock. Historic educational and economic barriers pose challenges for incentivizing low-income homeowners to retrofit their homes. Proactive strategizing that considers both educational and economic factors are needed to see increased retrofit adoption amongst these groups. Policy makers need an understanding of retrofit impact for more effective resource allocation and homeowners need better incentives, and tools to conceptualize the benefits, time commitment and cost associated with deep retrofits. To address this problem, we present a retrofit pathway modeling framework to accurately predict the time required to achieve comprehensive retrofits for the homeowner. Taking retrofit cost and annual energy saving into account, we are proposing a new Government sponsored and led financing program inspired by the successful 401(k) retirement plans and level 529 saving programs, which offers an either 2x or 3x match to the annual investment the homeowner commits to saving each year to ensure low-income homeowners are accounted for in the journey to building sector decarbonization by 2050 and beyond. For a case study home in the Grove Park neighborhood located in Atlanta, Georgia, hot water heat pump retrofits are the most impactful on building annual energy use but retrofits that have low cost and short payback periods such as installing LED light fixtures and low-flow showerheads are the recommended have the largest potential for shortening the years required to achieve comprehensive retrofits and therefore, are recommended for policy makers to incentivize in the community. Strategic financing can be used to ensure a financially feasible pathways for homeowners with varying annual budget amounts. For the example home, the program allows homeowners who invest only $50 annually to achieve comprehensive retrofits four times faster than if they only utilize existing incentive programs. Individual building energy simulation combined with socioeconomic analyses are needed to meet the needs of diverse low-income communities across the United States.

From Liquid to Stone: Reimagining the design of concrete structures for reuse

2024-10-17T03:01:14Z

From Liquid to Stone: Reimagining the design of concrete structures for reuse Donovan, Inge; Schnitzler, Jenna Every year, 360 million metric tons of concrete construction waste are sent to landfill in the United States, in large part originating from the demolition of economically obsolete buildings. Meanwhile, global demand for new concrete is accelerating – in 2021, the production of new concrete was responsible for up to 9% of global CO2e emissions, and our dependence on concrete is only expected to rise over the next 50 years. Concrete’s ubiquity is reinforced by its liquidity; it is simultaneously invisible and ever-present, undergirding global modernization through its cheap, local nature and its ability to take on any form in quick order. However, design with concrete has remained mostly unchanged, with inefficient, irreversibly fused structures cast in place to meet quickly changing programmatic needs, few of which survive longer than 30-50 years. Due to its careless application, concrete is perceived as a low-value material, and is therefore used wastefully, discarded quickly, and usually downcycled. The monolithic and inflexible nature of reinforced concrete structures perpetuate concrete’s culture of obsolescence and demolition. To meet emissions targets and demand for building, we need to close the loop by developing a circular economy of structural materials. Instead of reusing salvage materials that have already entered the waste stream, this thesis confronts the design of new concrete structures directly, presenting the design of and methodology behind Pixelframe, a precast kit of parts for reconfigurable concrete structures. In a future where buildings are increasingly seen as stockpiles for subsequent reuse, the reinvention of concrete structures is an imperative that presents an opportunity for a new tectonic – concrete is no longer a liquid poured once and cured on site, but instead is a material more akin to stone, retaining value across multiple lifespans.

Modeling technology pathways and retrofit adoption to achieve city-wide building emissions reduction goals

2024-10-17T04:12:50Z

Modeling technology pathways and retrofit adoption to achieve city-wide building emissions reduction goals Berzolla, Zachary M. Achieving net zero emissions from buildings by 2050 is an unprecedented challenge that will require an all-in effort at local, state, federal, and international levels. The exact path to reach this goal in existing buildings varies widely from one community to another. Thus local planning efforts and a bottom-up approach is needed to attain emissions reduction goals. This dissertation lays out a framework to create technology pathway roadmaps to help cities around the world identify actionable strategies to achieve their building emissions reduction goals. These “technical potential” roadmaps can help policymakers quantify the exact requirements in terms of retrofits, workforce, and material to attain their end goals. The application of these tools in 24 cities around the world are discussed. A sound roadmap is only as good as its implementation, and currently retrofit rates lag what is necessary to achieve 2050 goals on time. One of the oft-cited barriers to retrofit adoption is the high upfront cost. This dissertation documents a survey carried out by the author and the resulting model used to help quantify households’ willingness to pay for retrofits. Leveraging the willingness to pay model enables policymakers to analyze the techno-economic pathways to their goals. Finally, one of the greatest challenges to achieve emissions reduction goals is the timeline of retrofit adoption. Under the current business as usual retrofitting rate, less than a fifth of the building stock will be retrofitted by 2050. To help policymakers grasp this temporal challenge, this dissertation introduces a novel application of technology diffusion models that can quantify retrofit adoption over time. The tools developed in this dissertation are aimed at providing communities of all sizes with data-driven insights to meet their ambitious but necessary building-related decarbonization goals in a timely manner.

Spatial Computing for Building Performance and Design

2024-10-10T03:50:28Z

Spatial Computing for Building Performance and Design Weber, Ramon Elias Accommodating urban population growth while reducing emissions from the built environment poses an unprecedented challenge to the architectural discipline. To enable more sustainable construction, the dissertation proposes a new computational design framework to investigate how building performance from an environmental and user perspective relates to spatial design. The dissertation surveys existing computational methodologies for design automation and identifies new opportunities and value propositions for architectural computing in design guidance, feedback, and optimization. Exploring methods that can be used to generate and optimize structural systems of buildings and interior layouts, a specific focus lies in the design of residential buildings. By applying generative design methods to building analytics, new ways for estimating the embodied carbon of a building and the environmental impact of system-level design choices can be explored. First, the research demonstrates how generative geometric algorithms can be coupled with structural simulations to accurately predict the structural material quantity and, through that, the embodied carbon of a building in early stages of design. Second, a new method for representing, analyzing, and generating spatial layouts – the hypergraph – is proposed, that captures the characteristics of any given floor plan. Unveiling new architectural opportunities through automatic geometry creation, the hypergraph shows potential to improve the quality of residential spaces in terms of environmental performance and access to daylight. Enabling new design tools for architects, it offers creative applications and new collaborative workflows for incorporating new spatial metrics in the design process. Allowing for new quantitative insights in building performance, the research demonstrates that spatial efficiency can outperform envelope upgrades in terms of carbon emission savings.

Nature-Based Coastal Adaptation: A Comparative Assessment to Inform Effective Implementation

2023-10-19T03:06:45Z

Nature-Based Coastal Adaptation: A Comparative Assessment to Inform Effective Implementation Winer-Chan, Rose As coastal adaptation planning becomes the new normal, governments have increasingly shifted a significant portion of new infrastructure from hardened “gray” structures toward natural and “nature-based” solutions (NbS): restored or constructed ecosystems that, by enhancing or mimicking natural processes, mitigate coastal hazards while offering socioeconomic, environmental, and public health benefits. However, the use of NbS remains limited due to uncertainty over cost and performance, a fragmented regulatory landscape, inconsistent planning tools, and the context dependence of NbS design. This thesis aims to explore these diverse uncertainties in detail by shedding light on the key factors and processes that may pose critical barriers or drive success during the implementation of nature-based coastal adaptation (NBCA) projects. This study employs stakeholder interviews to explore and compare four NBCA case studies from design through implementation: Hunter’s Point South Park and West Pond in Queens, New York; Rose Larisa Park in East Providence, Rhode Island; and the Sand Motor in South Holland, the Netherlands. By identifying the common challenges, success drivers, and success metrics shared across these projects, this thesis hopes to provide useful early insights that help NBCA decision-makers thoughtfully define and measure success, anticipate key challenges, and take steps to overcome those challenges and achieve more successful implementation.

Generative Structural Design: An Algorithmic Approach to Synthesizing and Optimizing Steel Lateral Systems

2025-12-02T19:27:34Z

Generative Structural Design: An Algorithmic Approach to Synthesizing and Optimizing Steel Lateral Systems Hirt, Natasha K.(Natasha Karolina) Mitigating the immense environmental impact of the built environment is an important objective for the architecture, engineering, and construction industries. As initial decisions around layout and configuration have significant effects on the structural efficiency of buildings and are difficult to revise later in the design process, it is essential to provide designers with accurate material quantity and embodied carbon estimates at early design stages. The diversity of architectural expression and complexity of structural calculation has made it challenging to develop a tool that is sufficiently accurate, adaptive, and automated to accomplish this goal. This thesis presents a methodological and an analytical contribution. A novel generative structural design method is proposed, taking low-fidelity inputs, such as those that might be considered during early-stage design, and outputting a high-fidelity structural model that can be analyzed and iterated. The algorithm is tested on 233 structures drawn from wild and synthetic datasets, and a comparative analysis performed between five lateral system typologies. The findings correspond with the literature, verifying the premium for height proposed by Khan as well as Samyn’s slenderness premium. The analysis demonstrates the utility of synthetic structural system design for individual building analysis and generates new knowledge about the relative efficiencies of different lateral system typologies at a range of heights. The method evaluates how computational tools, such as design space visualization and topology optimization, may be realistically integrated into generative algorithms. Finally, the rich data produced with generative structural design reveals new ways to visualize, analyze, and understand the ways in which designers’ choices affect the ultimate efficiency and environmental impact of built structures.

Physics-based Estimates of Structural Material Quantities for Urban-level Embodied Carbon Assessment in Buildings

2023-08-01T03:02:30Z

Physics-based Estimates of Structural Material Quantities for Urban-level Embodied Carbon Assessment in Buildings Sory, Leïlah Yadia Kelly Decarbonizing the built environment requires immediate actions to meet global climate targets. The world population growth and rapid urbanization rate add to the urgency of this challenge. In fact, buildings account for about 40% of all energy and carbon emissions from operations and materials’ production and construction processes. More specifically, buildings’ structural systems are responsible for a significant share of the upfront embodied carbon emissions before construction. Most LCA tools focus on fully detailed material takeoffs from high-resolution Building Information Models (BIM) and are therefore incomplete during conceptual design. Moreover, Urban building energy modeling (UBEM) is a proven technique allowing cities to evaluate technology pathways to achieve their net-zero emissions goals. It involves simplified building archetypes to estimate operational energy on a large scale with reasonable accuracy. However, little attention has been paid to urban-level embodied carbon assessment. Therefore, this thesis investigates the potential of implementing physics-based structural quantities estimation in early-stage design for embodied carbon quantification at the urban scale. This approach combines bottom-up engineering calculations with data-driven surrogate modeling to automatically predict embodied carbon from a high-fidelity model. Finally, structural parameters are defined into energy model archetypes to deploy this method into an existing urban scale modeling tool. The feasibility of the proposed methodology is assessed through case studies to estimate embodied carbon and energy use intensities at the individual-building and urban scales. Results show the benefits of spatially mapping the distribution of embodied and operational carbon in the building stock and obtaining more nuanced estimates of carbon emissions compared with existing benchmarking studies. The primary use case of this work is to better inform planning and policy decision-making for retrofitting strategies and future building design.

Early Stage Embodied and Operational Analysis for Guiding Sustainable Architectural Design Decisions

2023-08-01T03:56:20Z

Early Stage Embodied and Operational Analysis for Guiding Sustainable Architectural Design Decisions Lyu, Yiwei Buildings account for a significant portion of global energy consumption and greenhouse gas emissions. Simulating building performance in the early design stage allows architects and engineers to adjust design decisions to reduce embodied carbon and energy consumption. Life-cycle assessment (LCA) is one of the most comprehensive methodologies to evaluate the environmental impact of architectural production and operation. This thesis aims to address the challenges involved in applying LCA to architectural design in the early design stage. By conducting a literature review of the status quo of architectural LCA and identifying the gaps in existing research and tools, this paper continues the research of a novel workflow in Grasshopper that calculates greenhouse gas (GHG) emissions and costs from both embodied and operational phases. The workflow addresses the early-stage uncertainty through random inputs with a Monte Carlo approach and implements surrogate models to accelerate the process for each iteration. The author's contribution to the workflow includes improving its robustness and accuracy by redesigning the simulation model to generate more accurate training data and transitioning to a new machine-learning algorithm. The results of the study provide insights into design decisions that can reduce embodied and operational carbon. A parallel case study was conducted to assess the trade-offs between embodied and operational carbon with regard to construction material selection. In the end, the thesis also proposes possible future research directions.

Eating On And Beyond The Infinite Corridor

2023-08-01T04:14:13Z

Eating On And Beyond The Infinite Corridor Searight, Tristan Infinite Stops are part of a design strategy for MIT’s Campus that aims to make eating well effortless and enticing. Approaches to improving wellbeing and community, in addition to reducing carbon emissions and resource use at MIT must account for the benefits of social, plant-based meals. Foodscape research uses the tools of architecture, GIS, behavioural economics, and participatory planning to explore how the relationship between daily life and the built environment shapes eating habits. Mapping parties invited members of MIT to describe their typical meals and spaces that support their social ideals. Typically, people walk a maximum of 5 minutes from previous and preceding activities to obtain meals which are eaten in 18 minutes or less. Work related convenience, cost, and the opportunity to run into friends often dictates where, what and how people eat. Social meals are valued, and people travel further to find spaces that exhibit an attractive social atmosphere in its architecture, menu, music, and hospitality. In combination with MIT’s geographic isolation from food places, time constraints make the spatial and cultural setting of the Infinite Corridor a key ingredient to people’s eating habits social opportunities. Infinite Stops are built structures that intervene on the corridor; punctuating its “corridic” setting with plant-based food linked with a variety of “staying” spaces. The Stops provide fast and slow meals which help connect and mediate the densely populated corridor space with the underutilised outdoor spaces. Infinite Stops presents a vision for MIT to leverage design—graphic, architectural and urban—to achieve its health, community and sustainability goals. Though they butt up against systemic socio-economic challenges, they hint at how over the course of a university program, teaching or staffing role, the occasional meal can create meaningful and positive behaviour change. The underlying approach and findings can empower planning departments to study their respective time-famished, work-driven foodscapes and find opportunities to support eating well across different mealtime needs.

Structural Steel Reuse as a Cost-Effective Carbon Mitigation Strategy

2023-08-01T04:22:04Z

Structural Steel Reuse as a Cost-Effective Carbon Mitigation Strategy Berglund-Brown, Juliana New structures can be designed from existing steel elements at lower cost and with dramatically lower carbon emissions when compared to conventional steel structures. Steel building structures typically have the highest embodied carbon impacts when compared to masonry, wood, concrete, and reinforced concrete projects (De Wolf et al 2016). Designing with salvaged structural steel is a beneficial alternative for structural engineers to reduce embodied carbon in the built environment and implement life-cycle oriented and cost-conscious design of steel structures. However, there are still many barriers to designing with reused gravity elements in buildings at scale, such as the uncertainty surrounding element availability, and understanding which factors contribute to carbon emissions associated with reuse. This thesis establishes more certainty about the supply of steel elements, quantifies potential carbon and cost savings, and identifies the variables that most impact such savings to better enable designing steel frames. This work first provides the context and terminology to connect structural systems to circular economy and reuse, and then outlines why reusing gravity beams and columns is particularly advantageous via a state-of-the-art overview of the steel value-chain. Next, a high-level material flow analysis is conducted for the U.S. structural steel market, indicating that the quantity of the existing steel heavy section scrap covers 140% of the demand for imports of steel. An LCA utilizing a comparative cut-off method is then performed and coupled with a cost estimation, which demonstrates a potential for around an 87% reduction in carbon emissions from steel reuse instead of recycling. Based on the findings of the partial LCA, an exploratory data analysis is then performed with both a stochastic sampling and nine real building projects to identify the variables most impacting carbon cost associated with reuse. Structural weight is found to have the greatest effect on reuse emissions, followed by number of elements, and then transportation distance. Finally, this thesis explains the implications steel reuse has for stakeholders in the structural steel industry, including fabricators and engineer and design teams. In short, this thesis presents the case for steel reuse, and the intrinsic carbon, cost, and structural value it could have.

Feeling Images of the Sun on Earth

2023-08-01T03:28:45Z

Feeling Images of the Sun on Earth Abou Ras, Ous We are solar societies with diverse relationships and practices that revolve around the Sun. But as mechanical systems became reliable, we retreated to thermally controlled environments away from the Sun. Energy became a utility to feed these systems. As the time spent indoors increased, energy demands rose alongside its greenhouse emissions; and the connection to our Star was reduced to a utility with a paradoxical duality: both as a valuable source of energy to be maximized, and a nuisance in the summer to be minimized. Dealing with this conundrum, architecture has divided sunlight into two experiential components. The aesthetic qualities of light are reserved for its visual phenomenon, while its thermal characteristic is either portrayed as a renewable energy source to be utilized outside of the design domain, or as a nuisance to be shaded from. In this thesis, I explore sunlight as a carrier of energy – where energy is seen as mass, and our visual and thermal experiences are determined by intensity and contrast of the mass of the Sun falling on Earth. Building off landscape practices that created diverse microclimates with sunlight, solar capturing techniques are analyzed and reimagined as parts of analogue machines that translate the homogonous array of sunlight falling on an outdoor public site into a landscape of concentrated energies. The proposal is a temporal field of hot – and perhaps even burning – surfaces that provide warm moments that act as urban hearths for people to collimate around in an otherwise cold empty park in Cambridge, Massachusetts. Leveraging recent advancements in computer graphics, a ray-tracing tool is developed to estimate solar collector energy output and visualize light concentration of different geometries and materials across varying solar positions. By repurposing solar technologies to heat small volumes for short periods of time, this thesis reimagines how we might view the Sun’s energy – from utility to a metaphysical cosmic mass– creating images that can be felt even on a cold cloudy day.

Human intent prediction for adaptive lighting based on a limited data scenario

2025-10-30T15:50:03Z

Human intent prediction for adaptive lighting based on a limited data scenario Sun, Jiamin (Researcher in architecture), author. An adaptive environment involves various ubiquitous computing and computer-aided technologies. It provides users with environmental supports such as lighting, air conditioning, motion assistance. Among the different control schemes, lighting is an essential element because it strongly affects people's visual experience and work productivity. The generalized residential lighting system is limited to create a personalized and responsive environment. Additionally, multiple and complex light sources make it difficult for users to obtain optimized lighting configurations. In general, an intelligent control system requires an extensive database of user habits in order to infer different user intents. In this work, we present a new personalized lighting control method that can learn explicit and implicit context though knowledge-based background and interactions. Instead of collecting a large amount of personal data, we explore the possibility to achieve a valid control method based on a limited data scenario. We consider language as one of the most important inputs from users when they are interacting with a smart environment. Although there has been a large amount of work in automatic control based on speech recognition, the situation is different for using language to control lights according to different preferences. In our study, on the one hand, multiple dimensions of representation of lighting status are studied and organized in a way that can be derived from people's language input. We have generated a learning model and a small database based on the hierarchy of different lighting settings. On the other hand, besides the learning part, we explore how users can directly teach the lighting system. That is, through continuous interactions, the control system learns users' profiles through limited interaction data and gradually becomes consistent with specific personal preferences. In addition to lighting control methods, we also introduce the different components of typical lighting systems and networks. This work contributes to fundamental knowledge in the areas of ubiquitous computing and home automation. This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Thesis: S.M. in Architecture Studies, Massachusetts Institute of Technology, Department of Architecture, 2019; Thesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2019; Cataloged from student-submitted PDF of thesis.; Includes bibliographical references (pages 75-80).

City Image: a dynamic perspective using machine learning and natural language processing

2023-04-01T04:01:32Z

City Image: a dynamic perspective using machine learning and natural language processing Wang, Rui The city image is a collective mental image of the city elements that can be perceived and interpreted by the public. The broader one’s understanding of the city image, the better urban design we will have. Over half a century ago, Kevin Lynch innovatively introduced this idea and summarized five physical elements – node, path, edge, landmark, and district, guiding the practice of urban design. Many subsequent studies confirmed its stability and further expanded the physical elements from a static viewpoint. However, cities are complex adaptive systems that involve both physical and subjective (affinity and reactions) aspects of temporal change. This thesis focuses on a dynamic perspective of not only physical but also subjective city images during both day and night, and in different timeframes. Taking advantage of machine learning, this thesis measures how the public values the city based on hundreds of thousands of geo-tagged photos and their textual descriptions. The thesis demonstrates the possibility of large-scale studies on the city image. To identify its subjective associations, natural language processing is applied to extract frequently used words and evaluate sentiment analysis, reflecting the public’s affinity and reactions, positive and negative. Results are presented in the form of data visualization maps and charts. Case studies examined two major US cities and their representative elements – Boston (Fort Point Channel and Boston Common) and New York City (World Trade Center, High Line, and Brooklyn Bridge Park). The main conclusion is that there does exist the subjective city image based on dynamic analysis of Lynch’s physical elements which plays a key role in an in-depth understanding of city image. Based on the state-of-the-art technologies and perspective, the thesis sheds light on a comprehensive understanding of city image, formulating a new criterion as a potential guide for urban planning.

Thermal Collectives Architectural Imaginaries Beyond Modern Comfort

2023-04-01T03:57:05Z

Thermal Collectives Architectural Imaginaries Beyond Modern Comfort Cousin, Tim; Faber, Olivier The era of abundance is over. The urgent need for CO2 emission reductions, combined with the rising price of energy and building materials, as well as restrictions on construction waste, call for alternative modes of building and inhabiting our cities. The notion of “comfort” implies practices of consumption that have shaped our cultural and sensorial experience of domesticity. But “modern comfort”, the one we know today, is a recent construct that was shaped in the aftermath of the post-war economic boom. Modern comfort is characterized by the transition from the tactical heating of human bodies in space to the global and uniform conditioning of spaces themselves —at all times and across all seasons. This was rendered possible by the development of fuel intensive HVAC systems and supported by complex curtain wall envelopes that have resulted in the industry-wide abandonment of thermal intelligence and its associated material practices. In a near future context of fuel scarcity, a group of people come together to confront the rising difficulty of maintaining their comfort. Their vision for living together in an alternative mode of dwelling calls for new forms of abundance in a world of scarcity, achieved through thermal intelligence. Their manifesto outlines the following fundamentals: • Living with thermal properties and climate • Collectivizing living spaces • Applying thermal intelligence to material ethics in construction and maintenance. The group surveys the numerous stranded modern office buildings on the outskirts of Paris. They acquire one of them at a bargain, and commission an experienced thermal architect to design the major spatial and infrastructural rearrangements to unlock the building’s passive thermal capacity. In support of the Thermal Collective’s new way of dwelling, the residents share their skills and build and maintain the interior fit out. We will follow the stories of some of the inhabitants as they construct, live in and care for their Thermal Collective.

Fibers and Fragments: Weaving local resources into the Arabian Gulf's modern material culture.

2023-04-01T03:16:20Z

Fibers and Fragments: Weaving local resources into the Arabian Gulf's modern material culture. Al Khayat, Latifa Khalil Yaqoob Considering the constraints of using solely local materials of the Arabian Gulf, this thesis explores two components that constitute a future construction practice: concrete in compression (mined from demolition sites) and carbon fibers in tension. The discovery of oil in 1932 accelerated the use of reinforced concrete in the Gulf, which was first spurred by British officials and economic agents in Bahrain. Ninety years later, the construction industry has yet to find a replacement for François Coignet’s steel reinforcement bar. Its corrosive nature is exacerbated in harsh climates and weakens reinforced concrete. This thesis responds to this challenge by drawing lessons from the practices of craftworkers before the era of oil extraction in the 1940s. The woven and mortared dwellings using palm fibers, clay, and stone provide productive analogs for the possibilities of using synesthetic fibers and concrete in future construction practices. The Crown Jewels feature a construction system of post-tensioned concrete rubble. Piercing, stringing, threading, weaving, and splicing lead to a more effective combination of carbon fibers and concrete fragments. These processes tie the two contrasting materials together: (1) Concrete derived from demolition of modernist blocks, which is frequently a devalued ‘waste’ material destined for landfills, and (2) Carbon fiber, which is a highly valued and energy-intensive counterpart. Although a technical endeavor, this thesis operates in a geography where Gulf states are trying to reinvent their economies and building practices. Yet, these states still maintain an affinity and adherence to British regulations set during its time as a protectorate. To that end, these proposed systems and materials are in alignment with a nationalist, developmental narrative, which is untethered from foreign norms and rather are rooted in prior material practices and cultures of building of the land.

Reshaping concrete: Empowering development through low-carbon structural design

2023-04-01T03:54:39Z

Reshaping concrete: Empowering development through low-carbon structural design Ismail, Mohamed Abdelbagi Less Economically Developed Countries (LEDCs) are struggling to meet the demand for affordable housing in their growing cities. There are several reasons for this, but a major constraint is the high cost of construction materials. In LEDCs, material costs can constitute up to 90% of the total cost of residential construction. Importantly, structural systems for multi-story housing in LEDCs are nearly always constructed in reinforced concrete and typically use structurally inefficient typologies like prismatic beams and flat slabs despite their structural material waste. This is because their construction mimics the materially inefficient practices of the More Economically Developed Countries (MEDCs), which were developed to reduce labor over material costs. The mounting use of steel-reinforced concrete structures in LEDC cities also raises concern about the environmental costs of construction; construction accounts for 20-30% of LEDC carbon emissions. This dissertation addresses these challenges with a set of strategies for the design and analysis of materially efficient concrete elements that can reduce the economic and environmental costs of urban construction. Developed to meet the constraints of LEDCs, structural elements are optimized to reduce the embodied carbon associated with the concrete and reinforcing steel while resisting the same loads as a standard building structure. These strategies include a novel approach to 3D shape parameterization, as well as a decoupled analytical engineering analysis method that accounts for the key failure modes and code-based constraints of reinforced concrete design. This method is verified through design examples that show how the embodied energy and carbon of concrete floor systems can be reduced by over 60% through shape optimization. Prototypes are fabricated and load tested to verify the efficacy of the structural design method, and to illustrate its ability to generate fabricable designs in an LEDC construction context. Finally, in order to broaden its potential impact, this research involves the development of accessible tools and methods for designers and stakeholders in LEDCs. The thesis presents an open-source toolset for the design and analysis of complex concrete elements and an intuitive design interface to communicate the performance and visual impact of materially efficient structures in real-time during early-stage design phases. This is especially useful in designs with exposed structural systems, allowing structural performance to play a key role in the final architecture. This thesis presents several strategies for the design of efficient concrete structures that allow us to build far more with far less, reducing the environmental and economic costs of construction while responding to the needs of LEDCs. These methods may enable the design of concrete elements for multiple performance criteria such as structural behavior, acoustic transmission, and thermal mass. They can also enable an accessible design practice through machine learning, real-time iterative workflows, and visualization tools that include the end user in the architectural design process. Keywords: reinforced concrete, shape optimization, digital fabrication, stress testing, machine learning, development, sustainability

Algorithmic planning for robotic assembly of building structures

2023-03-03T03:20:48Z

Algorithmic planning for robotic assembly of building structures Huang, Yijiang This thesis develops the algorithmic foundations for applying automated planning techniques to program robots to assemble discrete spatial structures. Benefitting from the robot’s capacity for moving, positioning, and holding elements precisely, robotic assembly aims to neutralize the cost and time impact of increasing demand for non-standard, customized designs using programmable robotics and automated process. Programming robots to assemble structures requires us to reason about the construction sequence and the robotic motions. The critical planning challenge is satisfying both stiffness constraints that limit the deformation of the structure and geometric constraints that ensure the robot does not collide with the structure. Current planning approaches either require a significant amount of human intervention or do not scale to the numeric scale and geometric complexity demanded by construction. As we shift from mass production in manufacturing to mass customization in construction, we need versatile planning tools that can adapt to different structural typologies, off-load tedious human programming work, and involve human expertise when relevant. This thesis addresses this need by proposing a unified algorithmic framework to formulate and solve assembly planning problems. Our investigations are grounded on three broad classes of assembly planning problems: (1) spatial extrusion, (2) pick-and-place assembly, and (3) robotic assembly with multiple tool changes. For each class of assembly problems, we propose scalable, efficient planning algorithms and test them with simulated and real-world case studies. This thesis demonstrates how algorithmic planning can provide us with a much smoother transition between an assembly design and its final execution on the robot. Based on these sound foundations of the "forward-evaluation" of robotic constructability in various contexts, we finally attempt to "close the loop" - deriving a metric to measure constructability and use it to guide the performance-driven exploration of a discrete design catalog.

Mitigating Peak Load and Heat Stress under Heat Waves by Scheduling Cooling and Energy Storage Systems

2023-01-20T04:04:25Z

Mitigating Peak Load and Heat Stress under Heat Waves by Scheduling Cooling and Energy Storage Systems Zhang, Zhujing As the climate changes, heat waves are becoming more frequent and severe. Exposure to heat waves could lead to heat stress. Heat waves intensify cooling demand and reduce air conditioner efficiencies. It causes peaks in electricity demand that pose operational challenges to the power grid. This thesis provides simulation-based methods to mitigate peak load and heat stress under heat waves by adjusting the schedules of the cooling and energy storage systems in buildings. This thesis demonstrates three scheduling methods: (1) cooling system scheduling, (2) energy storage system scheduling, and (3) combined cooling and energy storage system scheduling. The cooling system scheduling methods involve (1) generating baseline and training data with EnergyPlus (𝐸𝑃) simulations, (2) fitting surrogate models that relate cooling system adjustments to the perturbations in purchased power and Standard Effective Temperature (𝑆𝐸𝑇* , a comprehensive measure of thermal comfort, which is found to be a useful measurement of heat stress), and (3) embedding the 𝐸𝑃 data and trained models in an optimizer to schedule cooling system adjustments. The methods provide closely predicted optimized solutions with less computation cost than solving the problem by brute-force 𝐸𝑃 simulations. The energy storage system scheduling method relocates the power discharging from the energy storage system based on 𝐸𝑃 simulated baseline grid purchased power and its average value. The scheduling of the cooling and energy storage systems combines the two methods above. Case studies of these methods on a single building and a six-building neighborhood in the climate of Miami and Kuwait are offered. In these case studies, the methods reduce peak load significantly while maintaining 𝑆𝐸𝑇* within comfortable ranges. Among the three methods, the combined scheduling of cooling and energy storage systems is able to reduce peak power the most.

Self-Shaping Mechanisms Prototyping of PneuKnit Systems

2022-08-30T03:32:53Z

Self-Shaping Mechanisms Prototyping of PneuKnit Systems AlHajri, Maryam A. Our surroundings are constantly in flux, whether it is changes in the environment or changes in those who inhabit it. However, most of our spaces and building components are designed for permanence and durability without acknowledging the nuanced fluctuations of the user’s behavior, lifestyle, or changes in the natural environment. The strive for building permanence, designed to resist change, contributes to the 100 million tons of wasted materials annually due to recurring renovations and remodeling that inevitably addresses these fluctuations. What if our parts were active and could sense, react, respond, adapt, and co-evolve with their inhabitants and surrounding context? Rather than building with static dormant components, this alternative presents us with opportunities to advance the built environment and rethink its interrelations with its users and its context, resulting in spaces that are performative and attuned to user needs. This thesis seeks to develop a typology of lightweight adaptable systems that are rapid and affordable to manufacture. It investigates the fabrication of responsive self-actuating mechanisms; specifically, hybrid pneumatic-knitted (pneu-knit) systems that are autonomous and adaptable to changes within the environment through embedded sensors. The integrated sensors detect the input stimuli–in this particular case study user proximity–transmitting the data to a signal processor and interpreter, which then generates output values for the air pressure settings. This acts as a direct informer and physical shaper of the pneu-knit system, whereby the differentiated shaping generates through the structure and the design of the pneumatic component. The contributions of this work include developing a fabrication framework and method to integrate the knitted, pneumatic, and sensing components for the assembly of affordable, adaptable, lightweight material systems that are attuned to their surroundings.

Using Urban Building Energy Modeling to Develop Carbon Reduction Pathways for Cities

2022-08-30T03:15:27Z

Using Urban Building Energy Modeling to Develop Carbon Reduction Pathways for Cities Ang, Yu Qian Cities have been the nexus of economic activity and growth, but they have an insatiable appetite for energy. In response to the challenges and potential impact of climate change, cities and municipalities around the world are developing climate action plans to reduce carbon emissions and enhance resilience of their built environments. However, policymakers require a data-driven method to identify the most impactful, economical, and feasible strategies – and further translate these to actionable policy levers. This research serves to democratize and facilitate the wider use of urban building energy models in cities and municipalities. First, key applications and use cases of urban building energy modeling (UBEM) are identified, and a minimum viable UBEM is introduced for each use case. This framework streamlines computational requirements, data, and calibration needs, promoting more rapid development and utilization of UBEMs. Second, a web-based framework to rapidly generate UBEMs for carbon reduction technology pathways is developed, subsequently piloted in the City of Evanston, and found to significantly reduce time and resources needed for developing and utilizing UBEMs. The approach was further validated in collaboration with policymakers and researchers in eight cities – viz. Braga (Portugal), Cairo (Egypt), Dublin (Ireland), Florianopolis (Brazil), Kiel (Germany), Middlebury, VT (USA), Montreal (Canada), and Singapore. Finally, conventional UBEMs typically only incorporate building properties and characteristics. This dissertation also presents an exploratory approach – using supervised and unsupervised data science / machine learning methods – to integrate building properties with socio-economic data from census for better inference and understanding of energy use in cities Each approach is documented with the relevant results compared against conventional modelling workflows and / or validated through real-world urban case studies. The major contribution is the development and validation of methods and frameworks that can rapidly and automatically generate UBEMs to help cities and municipalities develop carbon reduction pathways to impact.

Airflow in Interior Spaces: Implications on Comfort and Health

2022-08-30T03:40:40Z

Airflow in Interior Spaces: Implications on Comfort and Health Kongoletos, Johnathan J. The International Energy Agency projects that rising income and greater access to air conditioning equipment in many developing countries will increase CO₂-equivalent emissions, energy consumption, and urban heat island effects. India exhibits these traits, where new building trends, hot climatic conditions, increasing social aspirations, and rapid population growth is likely to spread the adoption of air conditioning. Within India, while air-conditioners are attainable, the financial cost of acquisition and operation preclude their usage by the population’s most vulnerable. To reduce the need for air conditioning and increase available building options, low cost and socially-acceptable options are necessary to reduce productivity losses and excess mortality. This work presents the results of long-term temperature monitoring within four occupied homes, builds a model for understanding the influence of material choice, and evaluates that model on the basis of a reduction in peak indoor air temperature and energy savings as compared to an equivalent air conditioner. Results from the occupied homes show a peak reduction in inside air temperature of 8.2 °C during the summer months relative to informal housing in the same community. Further, using scale models and input from the Ramdev Nagar community in Bhuj, the impacts of operational airflow changes are quantified with a focus on next-day thermal comfort. Applicable outside of India, the techniques can be used concurrently with active cooling systems to reduce energy consumption or extend capacity. Targeting near-term implementation in India, this work focuses on tangible improvements spanning construction and operation. Shifting towards offices using chilled beams, this work presents data on the impact of ceiling fans on chilled beam performance both in steady-state and in transient situations to address discomfort in conference room settings where rapid changes in cooling performance are required or capacities exceeded. This work extends on that theme to propose improved thermostat placement targeting the reliability of the thermostat readings to serve as a proxy for thermal comfort. Finally, this work looks at dispersion of bioaerosols within a classroom environment. Via simulations, this work contributes through the quantification of different ventilation approaches and generalizable recommendations for contaminant control at the breathing zone.

Thin shell foundations: Embodied carbon reduction through materially efficient geometry

2022-08-30T03:11:45Z

Thin shell foundations: Embodied carbon reduction through materially efficient geometry Feickert, Kiley Anne Due to increasing global population, floor area is expected to double by 2060. At the same time, the building sector contributes 11% of global greenhouse gas emissions annually as a result of current construction processes. Therefore, if global warming is to be limited to 1.5ºC above pre-industrial levels, reducing embodied carbon will play a key role and business-as usual construction processes must be reconsidered. This research aims to reduce carbon emissions associated with reinforced concrete structural elements while addressing the need for a significant increase in adequate housing due to rapid urbanization. The structural floor system, frame and foundations represent the systems with the most potential to limit emissions, as they are the biggest contributors to embodied carbon in a building. In contexts where labor costs drive construction costs, particularly in the Global North, material is consumed excessively at the expense of time. This research proposes shell foundations in lieu of spread foundations, drawing from historical applications such as Félix Candela’s Customs Warehouse, built in 1953. Shells distribute loads more efficiently through their cross-section, reducing the quantity of material required structurally which ultimately reduces their embodied carbon. In this research, existing analytical equations are applied in a parametric design workflow to evaluate the environmental impact of conventional prismatic foundations and shell foundations for the same design load. For a 2MN column load on clay soil, shells reduce embodied carbon in foundations by 48%. By applying this approach systematically, insights are gained regarding their applicability to various building typologies and site conditions. For high applied loads, and soils with low bearing capacity, shells significantly outperform their prismatic counterparts. Foundations are then considered within the context of a whole building to determine the potential downstream savings when multiple systems are shape optimized. When floor slabs are shape-optimized in addition to using shell foundations, the embodied carbon of a building can be reduced by 72%. Digital fabrication offers a pathway to economically build materially efficient foundations while addressing the additional time and labor often associated with more complex geometry. For example, advances in 3D printing earth suggest local soil can act as formwork if printed in the required shape to receive the shell geometry. Additionally, subtractive methods are explored, where earth is compacted and milled to create formwork for a shell foundation.

Interactive Procedural Design Exploration for Modular Structures

2022-08-30T03:48:32Z

Interactive Procedural Design Exploration for Modular Structures Rao, John Huanshuo This thesis presents a grammar-based methodology for generating and evaluating structures that are constructed as aggregations of modular units. Using modular units as a building system can be more efficient for construction and potentially high performing structurally. Most of modular structures today are built in simple stacks which clearly advantages construction efficiency and the structural load transfer. However, other more complex configurations of modules might better address other important design factors such as daylight availability and the creative design intent of the architects. With the goal of expanding the design exploration process for modular structures, this thesis proposes a new methodology that integrates procedural design generation using shape grammars and structural performance evaluation using finite element analysis. Algorithmically, this paper takes inspiration from recent advances in discrete modeling tools. Under the existing frameworks, aggregations can be generated following either stochastic procedures or deterministic procedures. However, using deterministic systems often yields expected results with limited diversity while using stochastic systems does not give designers direct control over the generation process. By controlling the stochasticity of the generation process based on user feedback and performance goals, the methodology proposed in this thesis generates design options that follow specific design intent yet provides unexpected results.

Optimization of Cable-stayed Bridges at the Conceptual Design Stage

2022-08-30T03:02:56Z

Optimization of Cable-stayed Bridges at the Conceptual Design Stage Oey, Olivia Conceptual design of cable-stayed bridges, which defines the structure’s geometry and typology in the early stages of design, has significant influence on the structure’s efficiency, cost, aesthetics, and constructability. However, conventional design approaches for bridge design places greater emphasis on detailed structural analysis than conceptualization, resulting in designers being stuck in an iterative design loop with a structurally inefficient system. This thesis looks at developing a user-friendly conceptual design tool in the form of efficiency curves, which relates the geometrical aspect ratio 𝐿/𝐻 of different cable-stayed typologies to its structural performance in terms of volume. By developing a parametric model in the Grasshopper environment, numerous design variables such as number of stay cables, span lengths, materiality, loading conditions, boundary conditions, and flexural rigidity in the towers and decks are able to be investigated and incorporated to obtain a more realistic behavior of the structurally indeterminate cable-stayed bridge. A series of design curves are proposed for the harp, fan, web, and semi-fan cable configurations. The performance of the forms improves from the web, fan, semi-fan to harp configuration under symmetric loads, and under asymmetric loads, the fan configuration performs better than the harp configuration. Furthermore, since the design curves converge with increasing number of cables, the use of a truss analysis is sufficient for conceptual design, provided that the number of cables is adequate; this design approach, however, does not apply for the web configuration. Furthermore, a region of ’flatness’, equivalent to a range of 𝐿/𝐻 ratios that lies within a 10% variation of the optimum design solution, is proposed for different typologies, material, and boundary conditions. Overall, the web configuration has the most restrictive design curve out of all the typologies, with a very tight range of optimum 𝐿/𝐻 ratio.

Meeting A Community’s Emissions Reduction Targets Using Urban Building Energy Modeling

2022-06-02T03:27:01Z

Meeting A Community’s Emissions Reduction Targets Using Urban Building Energy Modeling Berzolla, Zachary M. Communities around the world are striving to meet aggressive emissions reduction targets in a short time frame. This paper lays out a six-step process using urban building energy modeling to identify a combination of building energy efficiency upgrades and renewable energy deployment strategies that meet emissions goals. The process involves key decision makers in each municipality working with an energy modeling consultant to build up a model of their building stock and simulate various scenarios to meet the desired emissions reduction goals. Through a case study of Oshkosh, Wisconsin, the six-step process is tested, and a concrete action plan to meet their 80% emissions reduction goals by 2050 is presented. The final recommended solution involves upgrading all residences in Oshkosh to ENERGY STAR certified home standards, installing cold climate heat pumps to displace fossil-fuel based heating, and deploying photovoltaics over an area equivalent to 50% of all rooftops. To aid in the final step of the process, implementation, the city-wide strategies were broken down into actions individual homeowners could take and what the cost and payback periods for these actions would be. In order to meet global emissions reduction goals, the six-step process presented in this paper will need to be carried out in communities around the world. The approach has been shown to be flexible and applicable to anywhere with emissions goals and access to building footprint and characteristic data.

Early Design Stage Building Lifecycle Analysis (LCA) of Cost & Carbon Impact

2022-02-08T03:11:34Z

Early Design Stage Building Lifecycle Analysis (LCA) of Cost & Carbon Impact Liu, Jingyi In my research, I have developed a building lifecycle analysis (LCA) workflow that recommends sustainable solutions based on the optimization of building lifecycle cost ($) and carbon impact (kgCO2eq). The workflow can analyze conceptual geometries in the early design stage when there is limited information. The first part of the workflow recommends sustainable features of building attributes, and the second part recommends detailed construction schemes. By following the recommended design solutions, the workflow helps save on average around 15% on cost, and around 25% on carbon impact in the U.S. Take a medium office building as an example; a 15% cost saving corresponds to around $9 million in the U.S. The workflow also reduces its analysis time to around 30 minutes, whereas analyzing a detailed model using conventional LCA tools takes hours. This new LCA workflow helps with data-driven design decision-making. It is unique because it ensures both performance and flexibility during the early design stage. As for attribute features, it recommends ranges for numerical attributes and rankings for categorical ones, which allows users to choose their preferred values or options. As for construction schemes, design diversity is quantified to produce various design solutions. The workflow also allows users to customize the minimum and maximum boundaries for numerical attributes and select their favorite categorical options, enabling users to tailor their design needs. The whole workflow is developed in Grasshopper, a code-friendly platform in the conceptual design software Rhino. Cutting-edge technologies are applied, including machine learning, optimization, data analysis, and visualization.

Generative Urbanism toward Thermal Synergy: Sustainable urban design for district heating and cooling

2022-02-08T03:34:43Z

Generative Urbanism toward Thermal Synergy: Sustainable urban design for district heating and cooling Wan, Qianqian Thermal performance has a long legacy in urban morphology, where the climate is interpreted explicitly in the forms of settlements. Mediating the temperature has taken a large portion in the energy sector since modern times. Besides the passive techniques, a closer observation of the space conditioning mechanism and the nature of thermal energy may produce systematic improvement in energy efficiency while maintaining the comfort level. Specifically, the synergy between heating and cooling needs in the urban environment provides the chance to circulate heat with low primary energy consumption. This thesis suggests heat recovery as a driving force in generative urban design, based on the echo between the mixed-use development ideology in the design world and the clustering of diverse user profiles suggested by thermal engineers. Contrary to the interdisciplinary collaboration convention, where urban design schemes are largely settled prior to the evaluation of infrastructural performance, this research explores the possibility to integrate engineering considerations into early phase design evolution and the impact of spatial features on energy performance. The thesis proposes the synergy score metric as a preliminary evaluation method to evaluate urban contexts and design schemes from a scope of thermal overlap between heating and cooling loads. Being naturally compatible with computational design optimization workflow, the metric bridges the iterations of design generation, performance assessment and multi-objective optimization, and navigates the design variants to approach greater heat sharing potential in the land use allocation scenario. The thesis then investigates the district heating and cooling network as the infrastructural system that embeds the synergy idea in essence. It examines the energy flow in a heat sharing network through simulation and analyzes the relationship between spatial sensitive features and energy performance metrics. The research explores the state-of-art performance-driven design optimization techniques and suggests a reproducible framework that couples design and engineering visions for integrated spatial and energy planning. Communicating at a methodology level in the design-engineering collaboration is the crux of contemporary smart planning toward a sustainable urban metabolism.

Heat Vulnerability and Risk Analytics for The Built Environment

2022-02-08T03:48:00Z

Heat Vulnerability and Risk Analytics for The Built Environment Bayomi, Norhan Magdy Climate change risks are considered one of the major global concerns that face humankind in the 21st century. Heatwaves have been identified as one of the deadliest climate hazards, especially in urban areas. Also, extreme heat events have been growing in intensity, duration, and frequency; more risks are expected to affect the urban population. Heat vulnerability assessment in the built environment is a complex process with multiple dynamics and components of human-natural systems and their interaction with the surrounding built environment. These dynamics include social, demographics, urban growth, environmental changes, access to public services, and policy impacts. Yet, there are considerable gaps in the literature on the effect of heat exposure and the built environment as a protective factor from potential vulnerability and risk perspectives. This dissertation addresses this need by developing a multifaceted and multi-scalar framework for heat vulnerability assessment. The framework is designed to inform decision-makers on the local dimension and the distribution of vulnerable populations by answering two key questions: where and what are the impacts of heat exposure in an urban setting? Who are the most susceptible populations to heat exposure? The dissertation explores vulnerability at multiple levels starting with a detailed assessment of the built environment by integrating the impacts of the physical characteristics of the existing building stock, available urban resources for long-term adaptation, and individuals’ adaptive capacity and potential health impacts under varying indoor exposure. Next, a methodology for rapid vulnerability analytics using novel technology such as aerial thermography coupled with Computer Vision (CV) and Machine Learning (ML) techniques to assess the thermal performance of building envelopes to provide actionable data for adaptation strategies at both the building and district levels. Finally, an evaluation framework to assess policy impact on the vulnerability of the urban system during heat events and how delays in the public policy response can increase risk levels

MASS BALANCE: Design strategies for lightweight, thermally massive construction systems

2022-01-15T03:21:23Z

MASS BALANCE: Design strategies for lightweight, thermally massive construction systems Gascón Alvarez, Eduardo The design of lightweight, thermally massive construction systems offers the opportunity to tackle two of the main challenges currently facing the built environment: the need to reduce the use of concrete, responsible for 5-8% of global carbon emissions, and the mitigation of the impacts of extreme heat events, which are becoming increasingly recurrent worldwide. This work presents new strategies to design and evaluate integrated construction elements that simultaneously consider their structural and thermal performance. Specifically, focusing on concrete floor systems becomes critical from both perspectives given their outsized contribution to structural mass and impact on thermal comfort. Methodologically, this thesis proposes the application of computational fluid dynamics (CFD) to study the dynamic thermal behavior of structurally optimized slabs. By simulating the ability of the thermal mass and ceiling’s geometric shape to flatten daily temperature fluctuations, the impact on occupants’ thermal comfort is evaluated. At the same time, the activation of these floor systems by, for example, embedding water pipes is analyzed as an additional opportunity of integrating functions and further improving the performance of these systems. The results obtained demonstrate the possibility of designing shaped slabs that, in addition to a 55% embodied energy reduction relative to conventional prismatic solutions, can still increase their passive thermal mass performance by 6.5% and their active cooling capacity by 14.5%. Moreover, the implementation of multi-optimization techniques allows for the exploration of Pareto-optimal designs that, at the expense of lowering the material savings achievements to 38%, can further improve their thermal behavior up to 9.5% (passive) and 28% (active).

Evaluating Overheating Preventative Measures in Residential Buildings and Passive Survivability

2022-01-15T04:07:29Z

Evaluating Overheating Preventative Measures in Residential Buildings and Passive Survivability Oladipo, Yesufu G. Buildings that are thoughtfully planned for future climate scenarios, designed well, and properly maintained have the potential to provide thermally comfortable environments. These same buildings can significantly reduce energy consumption and decrease CO2 emissions. This research evaluates the impact of the use of natural ventilation and modifications to the exterior wall to decrease the probability of heat-related illness and overheating. Assessments within this research are within a two-story residential building. The outdoor weather data selected for the assessments is from New York, NY during an extreme hot week. Assessments made within this research are intended to give guidance on the selection of the most appropriate combination of exterior wall properties and natural ventilation strategies within a well-insulated and tightly sealed building. The daily operations of buildings and the number of occupants in buildings generate internal heat loads. Additionally, indoor air temperatures are impacted by solar heat gain from glazed openings and heat transmitted by conduction through exterior wall surfaces. Natural ventilation strategies can reduce indoor air temperatures and increase air velocities close to the skin. Increasing air velocities close to the skin can supplement an individual’s thermoregulatory system. Air flows near the skin allow the body to expel heat in a manner that reduces the necessity of skin wettedness. Skin wettedness aids in reducing the surface and core temperatures of an individual through the dissipation of heat. Both surface and core temperatures can help to indicate the level of heat stress encountered by an individual. The primary metric used in this research is the thermal sensation standard effective temperature (SET). Standard effective temperature incorporates heat loss to the environment and an evaluation of it is currently recognized by LEED as a measure to promote passive survivability. The results from the simulations in this research show a drastic distinction for the potential of heat stress between the models that use natural ventilation through open windows and open interior doors versus models that do not.

On the Relationship Between Spatial-Temporal Outdoor Thermal Comfort Simulations and Bike Ridership

2022-01-15T03:30:44Z

On the Relationship Between Spatial-Temporal Outdoor Thermal Comfort Simulations and Bike Ridership Young Li Wen, Elizabeth Lyn Predicting resident comfort throughout a city over time and predicting the impact of these thermal sensations on mobility mode choice are key information required by urban planners and policy makers to promote and implement thermal comfort concepts. The Universal Thermal Climate Index (UTCI) has been linked to outdoor activity patterns and used to evaluate the effectiveness of urban interventions to improve thermal comfort. However, calculating the UTCI at high resolutions in urban spaces is complex as it requires inputs such as the ambient temperature, relative humidity, wind speed and mean radiant temperature at the point of interest. This thesis investigates how simulating the urban environment at increasing levels of spatial refinement impacts UTCI values along three bike routes in Cambridge, MA. As a baseline, UTCI is estimated using data from a local weather file. Then, shading from buildings and trees along the routes are considered. Next, local wind speeds are incorporated from computational fluid dynamics simulations. Finally, surface temperatures of the surrounding environment are included. Subsequently, with the UTCI simulations and publicly available bike ridership data from Bluebikes, Boston’s bike-sharing program, the relationship between bike ridership patterns and UTCI values along each route is studied. Supervised machine learning models are applied to predict bike ridership based on UTCI and other predictors. UTCI simulation results show that incorporating the various increments of spatial resolution does influence hourly UTCI values and the comfort bands that they fall into, especially in urban areas. Incorporating local wind speeds provides the largest impact on UTCI values, and causes a 10% reduction in annual cold stress hours. While the increments in spatial refinement also impacts UTCI in unshaded and exposed areas, the impact is smaller than in urban areas. The statistical models trained to predict hourly bike trip counts based on UTCI and other demand and weather predictors achieved a root mean squared error of 1.02 trips. 48% of predictions were correct, and an additional 40% of predictions were off by 1 trip. This thesis demonstrates the importance of spatial refinement in simulating UTCI, and motivates future research into efficient simulation methods or rules-of-thumb for deriving spatial-temporal UTCI values. Future work into building a robust predictive model would motivate the design of thermally comfortable environments for human-powered transportation in cities.

Machine Learning for Human Design: Developing Next Generation Sketch-Based Tools

2022-01-15T04:00:55Z

Machine Learning for Human Design: Developing Next Generation Sketch-Based Tools Ong Wen Xi, Bryan Formal computational approaches in the realm of engineering and architecture, such as parametric modelling and optimization, are becoming increasingly powerful, allowing for systematic and rigorous design processes. However, these methods often bring a steep learning curve, require previous expertise, or are unintuitive and unnatural to human design. On the other hand, analog design methods such as hand sketching are commonly used by architects and engineers alike. They constitute quick, easy, and almost primal modes of generating and transferring design concepts, which in turn facilitates the sharing of ideas and feedback. In the advent of increasing computational power and developments in data analysis, deep learning, and other emerging technologies, there is a potential to bridge the gap between these seemingly divergent processes to develop new hybrid approaches to design. Such methods can provide designers with new opportunities to harness the systematic and data-driven power of computation and performance analysis while maintaining a more creative and intuitive design interface. This thesis presents a new method for interpreting human designs in sketch format and predicting their structural performance using recent advances in deep learning. Furthermore, the thesis will also demonstrate how this new technique can be used in design workflows including performance-based guidance and interpolations between concepts.

Structural design synthesis using machine learning

2025-10-30T15:50:03Z

Structural design synthesis using machine learning Danhaive, Renaud Aleis Pierre Emile. This dissertation investigates how data-driven methods may support creative, performance-informed design processes for early-stage building and structural design. Given the imperative to curb greenhouse gas emissions, designers have an increased responsibility to consider the environmental impact of their decisions early on in the design process when they have outsize effects on a building's environmental performance. Although existing methods of optimization and design space exploration can guide designers toward better design options based on simulation data, there remain significant hurdles to the effective adoption of these tools despite their potential benefits. First, many engineering simulations remain cumbersome to connect with and slow to run, disrupting the pace of a fluid design process. Second, the design spaces used to generate and evaluate design variations are so vast that they are virtually impossible for humans to effectively explore. Finally, due to the intrinsically human nature of architecture and design, there is strong resistance to any process which purports to fully automate it. This dissertation addresses these challenges by proposing three strategies that capitalize on recent advances in deep learning to connect the power of performance-driven computing with the fluidity and creativity of human design and help human designers explore complex structural design spaces more intuitively. The first approach uses convolutional neural networks to expand surrogate modeling, which substitutes fast data-driven approximations for slow engineering simulations, from the prediction of single metrics to entire simulation fields. This reveals how performance is distributed spatially, providing more holistic feedback than previously possible. Two case studies show how this can uniquely link shape exploration and design materialization in fast and responsive ways. The second strategy introduces a sequential sampling algorithm that can help increase the effectiveness of many data-driven design approaches by helping build high-quality design datasets. Finally, the third approach takes advantage of the proposed sampling scheme to train deep generative models with low-dimensional latent spaces that can be intuitively explored by human designers to synthesize diverse structures with prescribed performance levels. Cases studies spanning different typologies and scales illustrate these approaches and demonstrate how harnessing advances in machine learning can amplify human creativity in structural design. Thesis: Ph. D. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, September, 2020; Cataloged from the official pdf of thesis.; Includes bibliographical references (pages 203-219).

Valuing design and designing value : the financial impact of daylight and views in office building real estate

2025-10-30T15:50:03Z

Valuing design and designing value : the financial impact of daylight and views in office building real estate Turan, Irmak İfakat. Architecture and finance both contribute to the conception and production of the built environment. Their agendas for buildings are sometimes in agreement and other times at odds. In this dissertation, I examine the intersection of architecture and finance by quantitatively assessing the economic value of design. Specifically, I measure the premium of two visual attributes--daylight and views--in office spaces in the borough of Manhattan in New York. Combining computational building performance analysis with empirical commercial rent data, I evaluate offices simultaneously as designed spaces and as property. First, I simulate spatially-distributed daylight and views in 5,154 offices. In the case of views, the hybrid performance-finance approach informs a new method for view modeling in an urban context. Second, using a hedonic pricing regression, I measure the premium for daylight and views in office rent prices. The results show that spaces with high levels of daylight have a 5 to 6% premium over spaces with low daylight; and spaces with high access to views have a 6% premium over spaces with low access to views. The combined value of spaces with both high daylight and view access, similarly, is 6%, indicating that the impact of daylight and views together is significant but is not additive. The identified premiums reflect how much more tenants are willing to pay for these attributes, holding all other building, neighborhood, and lease contract characteristics constant. At a moment when the affordability and sustainability of the urban built environment are in question, identifying the financial value of spatial characteristics can inform the production and regulation of properties. Architectural design and the flow of real estate capital are among a multitude of factors that collectively impact the creation of buildings. Combining methods of building performance analysis and financial modeling, this dissertation presents a new lens through which to understand how spatial design relates to economic forces governing our built world. Thesis: Ph. D. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, September, 2020; Cataloged from the official pdf of thesis.; Includes bibliographical references (pages 143-151).

Hydroponic container farms : validation of a building energy model and its integration in urban design

2025-10-30T15:50:03Z

Hydroponic container farms : validation of a building energy model and its integration in urban design Liebman-Peláez, Mariana. Controlled environment agriculture (CEA) systems, or plant factories, have developed within the urban context following efforts to expand local food production and provide an alternative to conventional agriculture with lower rates of greenhouse gas emissions and resource consumption. One urban CEA system, container farms, consist of vertical hydroponic farms inside retrofitted shipping containers. The artificially controlled interior environments within container farms along with their portability and modularity allow container farms to grow food in a variety of otherwise unused locations regardless of climate and daylight availability. While container farms and plant factories in general may provide a promising option for sustainable urban agriculture, they are highly energy intensive, particularly for lighting and thermal control. As a result, urban designers and policy makers require holistic assessment tools and methodologies to understand the viability of plant factories in reducing the greenhouse gas emissions of food systems. However, due to limitations of building performance simulation (BPS) tools, existing urban design methodologies assess the energy use of plant factories using simplified building energy models that omit the energetic effects of plants. While previous studies have developed methods that consider plant-air interactions within BPS tools through the use of co-simulators, to date there has been a lack of energy validation studies for such models. This research attempts to bridge this gap by validating a first-principle hourly energy model for an operational hydroponic container farm located in Boston, Massachusetts. The energy model (NMBE of 3% and CV[RMSE]of 9%) combines a plant evapotranspiration model in parallel with a BPS tool, EnergyPlus. The validation focuses on the reliability of the energy model in predicting hourly conditioning loads and comments on the practical challenges and limitations of modeling hourly conditioning for container farms and other plant factories. Second, this research uses the validated energy model to simulate methods for reducing conditioning loads of container farms under various climate and upgrade scenarios. Finally, this research explores the integration of container farms in an urban neighborhood and the potential for reducing additional demands on the neighborhood's energy supply system. Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, September, September, 2020; Cataloged from the official PDF of thesis. "September 2020."; Includes bibliographical references (pages 53-56).

Examining the feasibility of a novel ground-storage cooling system

2025-10-30T17:03:45Z

Examining the feasibility of a novel ground-storage cooling system Tang Liwen, Nicole. The Boston climate is known for its long, cold winters but it also suffers from hot, humid summers. The dehumidification needed to maintain occupant comfort in summer is often provided by condensing the excess moisture onto surfaces cooled by cold water. The systems currently used to provide the cold water have limited efficiencies, so alternative systems must be sought in order to achieve reductions in building energy use and to reduce the rate of climate change. This research examines the feasibility of a ground-cooling storage system that stores the abundant Boston winter cold in an underground block of soil to provide dehumidification in summer. In winter, heat exchangers use the cold air to produce cold water, which flows through a set of pipes in the soil block, cooling the soil. In summer, the cooling stored in the soil block is used to provide cold water for the dehumidifier, thus meeting the latent cooling loads of the building. The physical scale of the system required was found to be reasonable, relative to typical building sizes. The soil block, which does not use any valuable program space, was sized as less than 10% of the overall building size and did not require deep excavation. Winter thermal modeling showed that the soil block could be fully charged in a typical winter season. The summer thermal modeling showed that the system can meet the majority of the building cooling loads and is capable of responding to cooling peaks. The system energy use is primarily driven by the use of the heat exchangers for winter charging. The system was estimated to have a coefficient of performance of 71, which is much higher than that of comparable systems used for dehumidification. In conclusion, this feasibility study found that the proposed system shows promising results as an alternative to conventional systems and is worth further investigation. Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, September, September, 2020; Cataloged from the official PDF of thesis.; Includes bibliographical references (pages 101-102).

Air quality impacts of crop residue burning in India and mitigation alternatives

2025-10-30T17:03:45Z

Air quality impacts of crop residue burning in India and mitigation alternatives Lan, Ruoyu, S.M. Massachusetts Institute of Technology. Crop residue burning is a leading contributor to air pollution and ill health in India. Despite current bans to curtail agricultural fires, burning persists because of a lack of alternatives that are both effective and politically viable. This thesis applies adjoint of the GEOS-Chem regional chemistry-transport model in combination with epidemiological and economic models to inform rational decision-making. First, this thesis estimates the premature deaths as 43,000-73,000 valued at 10-23 billion USD in India attributable to exposure to ambient fine particulate matter (PM2.5) from crop residue burning, and finds Punjab, Haryana, and Uttar Pradesh contribute the majority (83%-95%) over 2005-2016, with 35-40% of impacts occurring in densely populated areas downwind. Second, this thesis quantifies the sensitivity of net impacts to potential changes in space and time, suggesting that relatively significant air quality benefits across India could be achieved in southeast Punjab; promoting burning earlier in the morning in November in Punjab alone could prevent up to 8,700 (95% CI: 5,700-12,000) premature deaths annually, valued at 2.2 (95% CI: 0.22-7.0) million USD. Third, this thesis compares the cost and benefit of mitigation alternatives for both the public and private sectors. The findings support the use of targeted and potentially low-cost alternatives rather than bans. Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, September, September, 2020; Cataloged from the official PDF of thesis.; Includes bibliographical references (pages 49-55).

Hydrological disasters : designing to shelter in place

2025-10-30T17:03:45Z

Hydrological disasters : designing to shelter in place Gonzalez- Placito, Alejandro. The focus of this thesis is hydrological disasters and the question it attempts to answer is: how can we design and implement housing structures along U.S. coastlines that fully withstand hydrological disasters? Priority and severity is shown by increasing trends in natural disaster occurrence frequency and damage and reconstruction costs. Cost increase is due in part because disaster events are more destructive, but also because of overbuilding and high housing density located within high risk areas. First, using several literature sources, this thesis analyzes various aspects of natural disaster response and education. This paper achieves its goal to increase awareness about the flaws in government risk management and lack of disaster awareness and mitigation design curricula amongst architecture institutions. As a design thesis, alternative housing models are presented in the later sections. The design process begins with hazard-risk identification and then outlining important building regulations. FEMA Coastal Construction Manual along with other sources were useful in understanding necessary mitigation measures required for coastal development designs. After research, a new design solution is presented. Design inspiration was drawn from similar technology and the need for innovative, resilient, and economical designs. This thesis hopes to use idealized designs to start more conversation about natural disaster defensive architecture. Thesis: S.B. in Art and Design, Massachusetts Institute of Technology, Department of Architecture, February, 2021; Cataloged from the official pdf version of thesis.; Includes bibliographical references (pages 49-50).

Illuminating preference : rethinking colored lighting in workplace environments

2021-07-05T14:03:20Z

Illuminating preference : rethinking colored lighting in workplace environments Lesina Debiasi, Lukas. Comfort in workspace lighting is hard to define. In recent years "smart hardware" has enabled personalized control in lighting. Provided interfaces, however are often forcibly tying the ephemeral nature of light and personal preference into a simplified interface. In this thesis, three new paradigms are proposed, emphasizing on personalization through sensing and matching preferred light to a given workplace task. Firstly a study attempts to find correlations between semiotic meaning and task on different media trying to establish pipeline for interaction. In a second example, the experience itself becomes the most essential part and is thus framed around the question, to whether sufficient knowledge of preference can be matched to nearby workplaces through methods oflearning. Thirdly in a personalized lighting setup, a microcontroller, equipped with a camera, uses image recognition algorithms tracking movement and pose of people in the room adjusting lighting condition to suit a given task. In summary, this thesis poses the question: how can personalized lighting rethought, to better allow for tasks in workplace environments? Thesis: S.M., Massachusetts Institute of Technology, Department of Architecture, September, 2020; Thesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, September, 2020; Cataloged from student-submitted PDF of thesis. "February 2020." Confirmed by MIT Registrar Office, graduation date is September 2020.; Includes bibliographical references (pages 69-71).

LIVING TINY

2021-07-05T14:03:20Z

LIVING TINY Jia, Effie. Living Tiny is a thesis that explores the role of architecture as a tool for designing both the built environment as well as the social realm of living. In a rapidly urbanizing world, the current pattern of city development results in unwanted isolation, expensive housing prices, and unsustainable growth. Can alternative forms of densification produce more appealing economical, social, and environmental results? This thesis proposes a design that builds upon the already existing infrastructure of alleyways and streets of typical urban neighborhoods. Through the implementation of a secondary scale, a new housing typology can emerge that satisfies the needs of the missing middle. Based on case studies of tiny houses and cohousing principles, Living Tiny envisions a two-part system of collective living that involves tiny house accessory dwelling units (ADUs) and communal buildings for shared amenities. Sited in Austin, Texas, the thesis presents its design for Mueller Tower District, a neighborhood featuring mixed-use zoning and a variety of housing typologies. The envisioned community benefits not only from the increased affordability and sustainability of living, but also from a greater quality of life through social interactions with the people around them. Through thoughtful, human-based architecture, cities of the future can avoid becoming concrete jungles; instead, they can become vibrant communities that support diverse, interconnected populations. Thesis: S.B. in Art and Design, Massachusetts Institute of Technology, Department of Architecture, May, 2020; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 59-61).

Mass reduction : opportunities and structural optimization methods to reduce material use in mass timber buildings

2025-08-23T03:22:59Z

Mass reduction : opportunities and structural optimization methods to reduce material use in mass timber buildings Mayencourt, Paul Louis. .Mass timber, a contemporary type of wood construction using engineered wood products, sourced from sustainably managed forests, has the potential to reduce the carbon emissions of the construction sector and act as a climate mitigation solution. Mass timber buildings made from renewable wood material can store carbon over their life cycles and support the regeneration of forests. Unfortunately, in the current market conditions in North America, a modern mass timber construction can cost up to 5-15% more than a conventional building, resulting in a low likelihood of wide adoption beyond green construction trends or environmentally conscious clients. There is, however, a missed opportunity in the way these buildings' structural systems are designed: up to 66% of structural material is under-utilized as a result of standardization because it is more convenient to manufacture. Structural optimization and new manufacturing techniques (i.e. digital fabrication) offer ways to design and manufacture customized structural elements with higher material efficiencies. This dissertation presents three new structural design methodologies to reduce cost through a reduction of material use in modern mass timber buildings. Each methodology addresses a standard structural element with high-recurrence and low material efficiency. The first methodology examines the design of hollow cross-laminated timber panels. The second methodology was developed to design shaped structural timber beams. The last methodology expands the design of shaped beam elements to frame structures. The results demonstrate that a total cost reduction of 5-7% can be achieved from structural material savings of 16-26%. A reduction of the total cost of mass timber structures is then likely to increase their competitiveness against other structural solutions and drive a greater implementation of sustainable mass timber as a climate mitigation solution. Thesis: Ph. D. in Architecture: Building Technology, Massachusetts Institute of Technology, Department of Architecture, February, 2019; Cataloged from student-submitted thesis.; Includes bibliographical references (pages 143-153).

Building an all-electric Volpe : a perspective on economic considerations and carbon emissions

2021-07-05T14:03:20Z

Building an all-electric Volpe : a perspective on economic considerations and carbon emissions Sharma, Charu,S.M.Massachusetts Institute of Technology. Recent studies show the need for deeper and faster cuts to global emissions if countries/cities are to meet goals set out in the Paris agreement. Buildings account for 35% of US greenhouse gas emissions and offer a unique opportunity to help reduce a large part of these emissions while providing net benefits. Buildings in the US rely on natural gas for 40% of their energy demand and primarily use it for space and water heating. This leads to higher emissions, leaky infrastructure, and public health risks because of poor indoor air quality. Devising economic alternatives that can help offset this natural gas dependency while making low energy-consuming buildings offers the best chance to reduce emissions at scale. In this thesis, we focus on exploring such alternatives by taking the case of a mixed-use site. We take the example of John A. Volpe National Transportation Systems Centre, Cambridge, a mixed-use site being developed by MIT consisting of housing, retail, offices, and laboratories. To analyze its carbon emissions over its lifetime, this research first estimates energy demand and compares two different energy sources - local electricity grid and an on-site cogeneration plant. Second, we analyze the use of natural gas for heating in each of the above supply scenarios in addition to making projections for future carbon intensity and energy costs. Third, we evaluate the impact of the recommendations in different landscapes by forecasting the price trend of electricity and natural gas and understanding their sensitivities to each scenario. Finally, using the performance metric of carbon emissions per person per year, this project analyzes relative emission variances in different scenarios. We find that an all-electric model is profitable for residential buildings and only marginally more expensive for other typologies over its lifetime than the baseline buildings. Thesis: S.M., Massachusetts Institute of Technology, Department of Architecture, May, 2020; Cataloged from the official PDF of thesis.; Includes bibliographical references.

Timber joinery in modern construction: Mechanical behavior of wood-wood connections

2021-07-05T14:03:20Z

Timber joinery in modern construction: Mechanical behavior of wood-wood connections Fang, Demi L. Timber joinery is a method of geometrically interlocking timber elements prevalent in historic cultures around the world, including North America, Europe, and East Asia. The use of joinery as structural connections faded with the development of metallic screws and nails. Two recent developments offer the opportunity to revive this historic timber connection type: 1) the increasing desire to reduce embodied carbon in buildings by replacing more components with timber as a low-carbon structural material, and 2) recent digital fabrication capabilities which enable the precise milling of complex geometries as an alternative to the time- and labor-intensive handiwork required previously. How can joinery connections be designed in modern structural joints? Can we quantify the sustainability advantage of using these all-timber joints in lieu of the modern convention of metallic fasteners? This thesis addresses both questions as applied to the Japanese Nuki joinery type, though the workflows may be applied to any joinery geometry. First, the rotational stiffness of the Nuki joint is characterized and cross-verified using multiple methods. Second, the embodied carbon of a gravity frame using Nuki joints is compared to that of a gravity frame using conventional metallic fasteners. The use of Nuki joints not only eliminates the use of steel and aluminum but also provides rotational stiffnesses that enable smaller beam sections to be used. It is shown that gravity frames designed with Nuki joints could reduce embodied carbon by over 70% compared to gravity frames designed using conventional beam hanger connections. The findings make a case for all-timber joinery connections to be implemented as a sustainable alternative to conventional metallic connections used in modern timber construction. Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, May, 2020; Cataloged from the official PDF of thesis.; Includes bibliographical references (pages [107]-112).

Computing embodied effort in the constructible design space of bobbin lace

2021-07-05T14:03:20Z

Computing embodied effort in the constructible design space of bobbin lace Elberfeld, Nathaniel Joseph. In recent years, research in design and computation has included processes of making as an expansion of the more established study of shapes with grammar formalism. This interest parallels a rise in craft practices as, perhaps, a counterpoint to the proliferation of digital fabrication in which fidelity to original specifications is considered crucial to the success of a project but whose means and methods are often obfuscated or of secondary importance. Making grammars (Knight and Stiny 2015), by contrast, offer an opportunity to examine one of the most important yet least understood considerations of a design: the effort it takes to physically produce it. This thesis introduces embodied effort as a contribution from human beings or machines that includes the work, steps, routines, applied skill, cognitive processing, or other forms of output that directly contributes to the production of a design.; To compute this effort, effort grammars are introduced to expand the formalism of making grammars to include an effort-cost tabulation that corresponds to moments of making. In these grammars, constructability is embedded in a design through an emergent topology in contrast to topologies that emerge through geometric optimization that may solve form or structural considerations but can be highly effortful and costly, or impossible to make. As a case study for computing embodied effort, an effort grammar is developed for a textile production technique called bobbin lacemaking to show how a limited set of making rules can achieve an infinitely variable, complex, and constructible design space. The grammar is used in conjunction with primary sources to identify the physical and cognitive effort required in each step of making bobbin lace and a mathematical model for calculating this embodied effort is introduced.; A computer program is written to automate the rules and effort computation on-the-fly and an exploration of the design space is discussed. Effort is situated as critical consideration of contemporary design practice. Thesis: S.M., Massachusetts Institute of Technology, Department of Architecture, May, 2020; Cataloged from the official PDF of thesis.; Includes bibliographical references (pages 115-118).

The constrained geometry of structures : optimization methods for inverse form-finding design

2021-07-05T14:03:20Z

The constrained geometry of structures : optimization methods for inverse form-finding design Cuvilliers, Pierre(Pierre Emmanuel) This dissertation aims to improve form-finding workflows by giving more control on the obtained shapes to the designer. Traditional direct form-finding allows the designer to generate shapes for structures that need to verify a mechanical equilibrium when built; however, it produces shapes that are difficult to control. This dissertation shows how the design of constrained structural systems is better solved by an inverse form-finding process, where the parameters and initial conditions of the direct form-finding process are automatically adjusted to match the design intent. By defining a general framework for the implementation of such workflows in a nested optimizer loop, the requirements on each component are articulated. The inner optimizer is a specially selected direct form-finding solver, the outer optimizer is a general-purpose optimization routine. This is demonstrated with case studies of two structural systems: bending-active structures and funicular structures.; These two systems that can lead to efficient covering structures of long spans. For bending-active structures, the performance (speed, accuracy, reliability) of direct form-finding solvers is measured. Because the outer optimization loop in an inverse form-finding setup needs to rely on a robust forward simulation with minimal configuration, we find that general-purpose optimizers like SLSQP and L-BFGS perform better than domain-specific algorithms like dynamic relaxation. Using this insight, an inverse form-finding workflow is built and applied with a closest-fit optimization objective. In funicular structures, this dissertation first focuses on a closest-fit to target surface optimization, giving closed-form formulations of gradients and hessian of the problem. Finding closed-form expressions of these derivatives is a major blocking point in creating more versatile inverse form-finding workflows.; This process optimizer is then reimplemented in an Automatic Differentiation framework, to produce an inverse form-finding tool for funicular surfaces with modular design objectives. This is a novel way of implement-ing such tools, exposing how the design intent can be represented by more complex objects than a target surface. Reproducing existing structures, and generating more efficient funicular shapes for them, the possibilities of the tool are demonstrated in exploring the design space and fine-tuned modifications, thanks to the fine control over the objectives representing the design intent. Thesis: Ph. D. in Architecture: Building Technology, Massachusetts Institute of Technology, Department of Architecture, May, 2020; Cataloged from PDF version of thesis.; Includes bibliographical references (pages [133]-145).

Optimization of Patterned Surface Structures

2021-07-05T14:03:20Z

Optimization of Patterned Surface Structures Rivera, Diego Alfonso. This thesis advances a recent work on the optimization of patterned surface structures used for architecture and structural engineering. On their own, well-designed surface structures--such as plates and shells--can be highly efficient, but by introducing specific aperture patterns, designers can further improve their potential for structural efficiency. Used as a way to invigorate an otherwise homogeneous architectural environment, even intricately patterned surfaces with highly complex geometries can be realized thanks to recent advancements in digital fabrication technologies. Most recent work on the integration of pattern design and structural optimization lacks general structural engineering applicability and does not address the incompatibility of traditional analysis methods with contemporary CAD environments.; This thesis, on the other hand, builds upon a method that employs the concept of isogcometric analysis to bridge the gap between CAD modeling and structural analysis and, in turn, lays the groundwork for structural pattern optimization in a more accessible computational environment. Initially introduced as a more systematic approach for exploring structural patterns, the studied method is further developed into a design workflow by the author of this thesis. Specifically, the presented research includes: adapting the previous method for more generic surface and pattern geometries, performing detailed parametric studies, and outlining an adaptive optimization framework more suitable for conceptual design exploration.; The design workflow is tested on five design case studies, which demonstrate that while the studied methods can be utilized for high-resolution analysis, using an adaptive framework yields comparable results and can save designers significant computational time in the early stages of design. Implemented by the author in Rhinoceros3D and Crasshopper3D, this expanded framework for structural pattern optimization illuminates a new and accessible avenue for designing patterned surface structures. This research provides designers a new way to synthesize architectural creativity and computational rigor in the early stages of conceptual design and even paves way for future research to further develop it into a robust design tool that can help designers marry architectural objectives and structural performance. Thesis: M. Eng., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, May, 2020; Cataloged from the official PDF of thesis. "May 2020."; Includes bibliographical references (pages 83-86).

Topology optimized hemispherical shell under asymmetric loads

2021-07-05T14:03:20Z

Topology optimized hemispherical shell under asymmetric loads Melcher, Grace(Grace E.) Domes are an efficient way to span long distances and resist gravity loads. The two kinds of classical domes prevalent in architecture are continuous shells and grid shells. Continuous shells are monolithic concrete or masonry; grid shells reorient material in lattice members to create depth throughout the shell thickness. This thesis considers the design of a topology optimized hemisphere, a hemispherical continuous shell, and a hemispherical grid shell, and compares the structural performance of these three shells under asymmetric loads. First, a novel topology optimized dome is defined and generated with the objective to minimize strain energy. Then a numerical study is conducted on the three shells, continuous, grid, and optimized hemisphere, to investigate the different structural behavior of each material design scheme. This includes a linear elastic finite element analysis of each hemisphere's response under its own buckling load. Finally, plastic analyses are presented including the effects of large deformations and material yielding to determine the optimized hemisphere's response in comparison to the classical hemispheres. The proposed method uses topology optimization over the new domain of a thin shell lofted into space, as opposed to the more common planar and three-dimensional spaces for structural optimization. This thesis demonstrates good correlation of load capacity between Timoshenko's theoretical predictions and numerical analysis using Abaqus. The proposed topology optimized hemisphere has a seven-fold increase in load capacity under asymmetrical loading, when compared to a grid shell of the same volume. Thesis: M. Eng., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, May, 2020; Cataloged from the official PDF of thesis.; Includes bibliographical references (pages 48-50).

Exploring mechanisms for improved air quality in Mumbai resettlement dwellings : evidence from fieldwork and simulation

2021-07-05T14:03:20Z

Exploring mechanisms for improved air quality in Mumbai resettlement dwellings : evidence from fieldwork and simulation Lueker, Justin(Justin David) In megacities like Mumbai, rapid urban migration has driven over half the population to reside in informal settlements known as "slums." The local government seeks more efficient use of scarce land and a higher standard of living for slum dwellers by resettling them in permanent multistory structures. However, existing resettlement schemes result in environmental conditions that are often no better than the places from which people were located, with dense clusters of high-rise buildings being referred to as "vertical slums." Thus it is essential to base design decisions on evidence-driven consideration of indoor and outdoor environmental quality. This project involves a measurement, simulation, and engagement campaign that focuses on one important element of sustainable design, household air pollution, an issue described as the most prevalent environmental risk factor worldwide. Household surveys revealed occupant behavior patterns and aesthetic preferences while a measurement campaign informed the primary pollution sources and the relationship between architecture and pollution exposure. While acknowledging the unique project constraints for the slum resettlement context, we identify air quality improvement mechanisms that are resource-efficient, scalable, and culturally sensitive. By strategically applying these mechanisms in tandem, the simulations suggest that passive strategies alone can reduce annual average pollution exposure by more than 95% for household occupants. Future efforts will include a trial application of proposed design alternatives in an occupied Mumbai apartment, as well as presentation of results to NGO partners and municipal housing authorities. Ultimately, this project seeks to motivate the addition of environment- and health-centric design practices to the architectural specifications of low-income residential projects in cities like Mumbai. This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2019; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 108-124).

Materially efficient structural floor systems for housing in India

2021-07-05T14:03:20Z

Materially efficient structural floor systems for housing in India Ismail, Mohamed A.(Mohamed Abdelbagi) .In 2015, the government of India launched the "Housing for All by 2022" initiative to build 20 million units of affordable urban housing for lower income groups. Thus far, they have built fewer than two million units. In India, it is estimated that material costs can constitute 60 to 80% of the total cost of residential construction. Nonetheless, their construction mimics the materially inefficient practices of developed countries, practices developed to reduce labor over material costs. As a result, prismatic beams and flat slabs are frequently used despite their structural inefficiency. In its current state, the construction industry is resource intensive and unsustainable. The mounting use of steel-reinforced concrete structures in Indian cities has also garnered concern for the environmental costs of construction; construction accounts for 22% of India's carbon emissions.; The impact of structural systems on a building's embodied energy are immediately apparent: cement and steel are responsible for nearly 90% of a multistory concrete frame building's total embodied energy, and at least 50% of that is in the horizontally-spanning elements alone. With no end to construction in sight, new practices are needed to curb the environmental and economic costs of India's construction. This thesis explores the design of materially efficient floor systems that can reduce the economic and environmental costs of construction. Utilizing computational structural design, this thesis presents several strategies for the structural optimization of one-way concrete floor systems. Designed for the constraints of India, the structural elements are optimized to reduce the necessary volume of concrete and steel while resisting the same loads of an equivalent solid prismatic beam or slab.; While structural optimization for material efficiency is not a new practice, it is technically challenging and often reserved for large-scale and exclusive architectural projects. Conversely, this research applies these principles to common residential construction. This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Thesis: S.M., Massachusetts Institute of Technology, Department of Architecture, 2019; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 137-139).

Design-integrated Urban Heat Island analysis tool and workflow : development and application

2021-07-05T14:03:20Z

Design-integrated Urban Heat Island analysis tool and workflow : development and application Awino, Hellen Rose Anyango. The Urban Heat Island (UHI) effect is a well-studied phenomenon broadly attributed to human activities that transform open terrain into cityscapes. Among global 21st-century concerns, projected trends in population growth, urbanization, and regional climate change could exacerbate the warming in cities and intensify the UHI effect. Yet, microclimate analysis essential to assessing UHI intensity is often neglected, resulting in poor planning practices with adverse effects on health, comfort and energy use within cities. With buildings responsible for substantial quantities of global energy consumption and carbon emissions, this context demands climate-responsive design to achieve better-performing cities. The UHI effect presents an urban design challenge, but only recently has there been a platform for design workflow integration.; Despite existing engines that accurately evaluate UHI intensity in urban environments, architects, designers, and urban planners have often not incorporated such simulation into microclimate studies due to prohibitively expensive computational costs, disconnected workflows within unintuitive or unfamiliar platforms, and uncertainty about difficult-to-obtain urban climatology parameters. These hindrances cause impactful delay within the design feedback loop and often generate a lack of confidence in the simulation process and output. This thesis proposes a Computer-Aided-Design integrated graphical user interface for the Urban Weather Generator (UWG), an urban-scale climate prediction tool developed by Bruno Bueno to simulate microclimatic conditions of urban sites using operational weather station data.; The goal is to make the powerful and computationally cheap engine accessible to design workflows by incorporating it as a plugin within the conventional design software Rhinoceros-3D, and by coupling it with the Local Climate Zone classification scheme developed by urban climate experts lain Stewart and Timothy Oke to standardize quantitative physical descriptions of cities. The proposed update automates geometric parameter extraction and implements a reliable means of urban morphological parameter estimation. As a case study, an iterative urban-scale design exploration is analyzed for selected climates. This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Thesis: S.M., Massachusetts Institute of Technology, Department of Architecture, 2019; "June 2019." Cataloged from PDF version of thesis.; Includes bibliographical references (pages 106-108).

Auto-calibrated urban building energy models as continuous planning tools for greenhouse gas emissions management

2021-07-05T14:03:20Z

Auto-calibrated urban building energy models as continuous planning tools for greenhouse gas emissions management Nagpal, Shreshth. To reduce greenhouse gas emissions associated with their buildings' energy use, owners frequently rely on building energy models that are calibrated to existing conditions for evaluation of potential energy efficiency retrofits. Development of such calibrated models requires the estimation of a series of building characteristics, a process which is extremely effort-intensive even for a single building and, therefore, almost prohibitive for large campus projects which often include hundreds of diverse-use buildings. There is a need for a framework that combines established urban energy model generation techniques with data-driven methods to reduce the manual and computational cost of developing calibrated baseline campus energy models, allow for real time evaluation of future building upgrades, and display their consequences to decision makers on an ongoing basis. This dissertation addresses this need by proposing new workflows for different development stages of models designed to evaluate future energy scenarios for large institutional campuses. First, the strengths and limitations of different urban modeling methodologies are assessed (modeling approach). Next, a methodology to employ statistical surrogate models is proposed for rapid estimation of unknown building properties (auto-calibration). Finally, a continuous energy performance tracking framework is presented to enable university campuses to manage their building related greenhouse gas emissions over time (continuous planning). As a proof of concept, the complete method has been implemented and tested at the author's home institution. Auto-calibration and continuous planning can be implemented independently or combined, and the dissertation includes a discussion about their possible impact if applied across the building stock. This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Thesis: Ph. D. in Architecture: Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2019; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 109-117).

Early building design using multi-objective data approaches

2021-07-05T14:03:20Z

Early building design using multi-objective data approaches Brown, Nathan C.(Nathan Collin) During the design process in architecture, building performance and human experience are increasingly understood through computation. Within this context, this dissertation considers how data science and interactive optimization techniques can be combined to make simulation a more effective component of a natural early design process. It focuses on conceptual design, since technical principles should be considered when global decisions are made concerning the massing, structural system, and other design aspects that affect performance. In this early stage, designers might simulate structure, energy, daylighting, thermal comfort, acoustics, cost, and other quantifiable objectives. While parametric simulations offer the possibility of using a design space exploration framework to make decisions, their resulting feedback must be synthesized together, along with non-quantifiable design goals.; Previous research has developed optimization strategies to handle such multi-objective scenarios, but opportunities remain to further adapt optimization for the creative task of early building design, including increasing its interactivity, flexibility, accessibility, and ability to both support divergent brainstorming and enable focused performance improvement. In response, this dissertation proposes new approaches to parametric design space formulation, interactive optimization, and diversity-based design. These methods span in utility from early ideation, through global design exploration, to local exploration and optimization. The first presented technique uses data science methods to interrogate, transform, and, for specific cases, generate design variables for exploration. The second strategy involves interactive stepping through a design space using estimated gradient information, which offers designers more freedom compared to automated solvers during local exploration.; The third method addresses computational measurement of diversity within parametric design and demonstrates how such measurements can be integrated into creative design processes. These contributions are demonstrated on an integrated early design example and preliminarily validated using a design study that provides feedback on the habits and preferences of architects and engineers while engaging with data-driven tools. This study reveals that performance-enabled environments tend to improve simulated design objectives, while designers prefer more flexibility than traditional automated optimization approaches when given the choice. Together, these findings can stimulate further development in the integration of interactive approaches to multi-objective early building design. Key words: design space exploration, conceptual design, design tradeoffs, interactive design tools, structural design, sustainable design, multi-objective optimization, data science, surrogate modeling This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Thesis: Ph. D. in Architecture: Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2019; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 201-219).

Peripheral timber applications for waste wood material in extreme climates and earthquake risk regions

2021-07-05T14:03:20Z

Peripheral timber applications for waste wood material in extreme climates and earthquake risk regions Brose, Andrew(Andrew John) Worldwide, discarded construction and demolition material account for 40% of all municipal solid refuse including residential, commercial, institutional, and agricultural waste flows (Elgizawy, El-Haggar, and Nassar 2016). Hong Kong sends over 200 tons of timber waste from old formwork and scaffolding to the landfill per day (Wang et al. 2016). After fulfilling their assumed raison d'etre, the cement-flaked shuttering boards and stubby scaffolding poles arrive amongst the discards, eventually deformed beyond utility. This thesis explores the possibilities of reusing wood that sits at the fringe of construction projects, in applications that bring back the beauty and elegance ingrained in the oldest of building material. In part, this project is a remolding of the perception of undervalued wood species and construction waste. This research proposes specific techniques, inculcating value into discarded wood material and bringing a new mechanism for the material production of timber existing at the periphery of design and construction. In application, this study considers solutions around natural fiber composites and timber space-frame roofs for affordable housing projects. A prototype space-frame using small diameter wood elements was constructed in India and made practical by the development of a simple joint system. Load testing of the frame provided positive results (2.3 kN/m²) and surpassed India National Building Code standards for roof design. In addition, waste wood fibers incorporated in cementitious wall and roof panels improved thermal insulation properties (0.164 W/m²·K) while increasing flexural strength (4.6 N/mm²). Prototype and samples were tested within the objectives of improved thermal comfort, increased earthquake safety, and reduced material cost. This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Thesis: S.M. in Architecture Studies: Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2018; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 63-66).

Automatic calibration of an urban microclimate model under uncertainty

2022-01-13T07:53:53Z

Automatic calibration of an urban microclimate model under uncertainty Mao, Jiachen Simulation models play an important role in the design, analysis, and optimization of modern energy and environmental systems at building or urban scale. However, due to the extreme complexity of built environments and the sheer number of interacting parameters, it is difficult to obtain an accurate representation of real-world systems. Thus, model calibration and uncertainty analysis hold a particular interest, and it is necessary to evaluate to what degree simulation models are imperfect before implementing them during the decision-making process. In contrast to the extensive literature on the calibration of building performance models, little has been reported on how to automatically calibrate physics-based urban microclimate models. This thesis illustrates a general methodology for automatic model calibration and, for the first time, applies it to an urban microclimate system. The study builds upon the previously reported and updated Urban Weather Generator (UWG) to present a deep look into an existing urban district area in downtown Abu Dhabi (UAE) during 2017. Based on 30 candidate inputs covering the meteorological factors, urban characteristics, vegetation variables, and building systems, we performed global sensitivity analysis, Monte Carlo filtering, and optimization-aided calibration on the UWG model. In particular, an online hyper-heuristic evolutionary algorithm (EA) is proposed and developed to accelerate the calibration process. The UWG is a fairly robust simulator to approximate the urban thermal behavior for dierent seasons. The validation results show that, in single-objective optimization, the online hyper-heuristics can robustly help EA produce quality solutions with smaller uncertainties at much less computational cost. Finally, the resulting calibrated solutions are able to capture weekly-average and hourly diurnal profiles of the urban outdoor air temperature similar to the measurements for certain periods of the year. Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2018.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 79-86).

Folding fan fac̦ade : designing an actuated adaptive fac̦ade system for fine-grain daylight control

2021-07-05T14:03:20Z

Folding fan fac̦ade : designing an actuated adaptive fac̦ade system for fine-grain daylight control Kim, June,S.B.Massachusetts Institute of Technology. In architecture, natural light is one of the main factors to consider when designing a building or a room. A building has to be designed in such a way to allow the right amount of natural light in which influences the building occupants' visual and thermal comfort level. Curtains, blinds, shades, or shutters are the most common static shading methods currently used to regulate the amount of sunlight coming into a room. However, traditional blinds or shades cannot be customized with respect to fine-grain localized control, which can result in suboptimal indoor lighting levels when the blinds or shades are down. While static window treatments are practical low-cost options, they cannot offer the level of adjustment that dynamic shadings can provide. Majority of the time, occupants of a room have the freedom to adjust the shades; however, the shades are often left in one position since occupants are not willing to constantly adjust the shutters every time the outside environmental conditions change. Unlike traditional blinds, adaptive fac̦ades are designed to automatically adjust positions depending on the environmental changes or have the ability to be fine-grain controlled by the occupant. Because of the ability to respond to fluctuating weather conditions, adaptive fac̦ades can provide optimal indoor day lit space. The purpose of this thesis is to design and build a proof-of-concept prototype of a folding fan-shaped actuated adaptive facade system. Because of the scope of this thesis, the prototype is designed to fit in one of the windows at McCormick Hall instead of a full scale building fac̦ade. There are 13 fan-shaped shades units that can be individually controlled to reduce direct sunlight coming into the indoor space. The results demonstrate that this technology can be designed and built with a modest budget and commonly available tools to achieve high quality results for customized daylight control. This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Thesis: S.B., Massachusetts Institute of Technology, Department of Architecture, 2018; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 57-58).

Design for infectious disease control in the developing world : the power of natural ventilation

2022-01-13T07:53:53Z

Design for infectious disease control in the developing world : the power of natural ventilation Anderson, Abigail M Contaminated particles in hospitals can spread from infected patients to those who are hospitalized for non-disease-related reasons. The reputation of hospitals, especially in the developing world, as places where diseases are spread rather than cured necessitates design strategies focused on stopping or controlling disease spread among patients. In this thesis, I examine the potential of architectural layout, among other factors, to reduce the spread of contaminants through passive ventilation strategies. Using Computational Fluid Dynamics, I propose a system of hospital rooms which minimizes contaminant spread among patients while maintaining comfortable airflow rates. Thesis: S.B., Massachusetts Institute of Technology, Department of Architecture, 2018.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 55-56).

Implementation and evaluation of thermal avoidance strategies in arid, cost-constrained climates aimed at improving indoor thermal comfort : a case study in Bhuj, India

2022-01-13T07:53:53Z

Implementation and evaluation of thermal avoidance strategies in arid, cost-constrained climates aimed at improving indoor thermal comfort : a case study in Bhuj, India Kongoletos, Johnathan J. (Johnathan James) The use of air conditioning in the buildings sector has been rapidly increasing. The International Energy Agency projects that rising income and greater access to air conditioning equipment in many developing countries will increase CO₂-equivalent emissions, energy consumption, and urban heat island effects. India is a prime example of a region where new building trends, hot climatic conditions, increasing social aspirations, and rapid population growth is likely to spread the adoption of air conditioning. To reduce the need for air conditioning, the research team has worked to develop, implement, and evaluate methods to reduce temperatures within the built environment using largely passive means. Building on the past work of Nelson and Gradillas, the thesis presents the results of long-term temperature monitoring within four homes in Bhuj, India. Results from the collective work have helped to inform future designs for the region, and resulted in an innovative roof concept. Using scale models, thermal simulations, and full-scale housing, results from the thesis explore new methods of implementing solutions for reduced solar heat gain, reduced heat absorption, and increased heat rejection. The research concludes by presenting early work on additional techniques and implications of using indigenous products to better thermal comfort conditions. Applicable outside of India, the techniques can be utilized in other regions and climates, as well as concurrently with active cooling systems to reduce energy consumption or extend existing capacity. Further work will seek to improve the design and adaptability of the system to different regions. Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2018.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 150-155).

Automated motion planning for robotic assembly of discrete architectural structures

2023-07-17T13:52:13Z

Automated motion planning for robotic assembly of discrete architectural structures Huang, Yijiang (Architect) Massachusetts Institute of Technology Architectural robotics has proven a promising technique for assembling non-standard configurations of building components at the scale of the built environment, complementing the earlier revolution in generative digital design. However, despite the advantages of dexterity and precision, the time investment in solving the construction sequence and associated robotic motion grows increasingly with the topological complexity of the target design. This gap between parametric design and robotic fabrication congests the overall digital design/production process and often confines designers to geometries with standard topology. In the goal of filling this gap, this research presents a new robotic assembly planning framework called Choreo, which eliminates human-intervention for parts that are typically arduous and tedious in architectural robotics projects. Specifically, Choreo takes discrete spatial structure as input, and then assembly sequence, end effector pose, joint configuration, and transition trajectory are all generated automatically. Choreo embodies novelties in both algorithm design and software implementation. Algorithm-wise, a three-layer hierarchical assembly planning framework is proposed, to gradually narrow down the computational complexity along the deep and branched search tree emerging in this combined task and motion planning problem. Implementation-wise, Choreo's system architecture is designed to be modularized and adaptable, with the emphasis on being hardware-agnostic and forging a smooth integration into existing digital design-build workflow. Case studies on fabrication results of robotic extrusion (also called spatial 3D printing) are presented to demonstrate Choreo's power on efficiently generating feasible robotic instructions for assembling shapes with non-standard topology and across the scales. Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2018.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 71-80).

Material matters : process of intuitive design

2022-01-13T07:53:53Z

Material matters : process of intuitive design Ryan, Anna K. (Anna Kathryn) Steady. Tighten. Splice. Bend. Fold. Weave. Elongate. Stiffen. Break: This is the vocabulary of an undertaking of craft, designing-while-making, improvising, learning-while-doing. This thesis is an exploration of design as craft. Woven plywood models are created in improvisational moves, benefitting from the embodied knowing that comes with extended material engagement. The making of these pieces is an experimental and playful process, where methods are tested and discovered by hand. The body is the driver in this way of making, and decisions are made based on the possibilities and limitations of the material. The plywood pieces are held together with friction alone. With no boundary conditions and no permanent fixatives, they are endlessly malleable, repeatedly remade into new forms, each time producing new lessons for the maker. Drawings are created after making, in order to map these undevelopable forms. The series of drawings are not representative of form, but are instead a method to unravel the story of making. The resultant family of structures advocate for designers to engage with material in order to make discoveries of forms and methods that would not have arisen using the hylomorphic model of design. Working by hand allows the material to assert its own logic, principles, and exciting possibilities. Thesis: M. Arch., Massachusetts Institute of Technology, Department of Architecture, 2018.; Cataloged from PDF version of thesis.; Includes bibliographical references (page 100).

Modeling of opening characteristics of an atrium in natural ventilation

2022-01-13T07:53:53Z

Modeling of opening characteristics of an atrium in natural ventilation Luo, Qinzi Atriums are widely applied in non-residential buildings to provide social contact, daylight, air circulation, and aesthetic requirements. Buoyancy-driven ventilation systems are common because they can maintain suitable thermal comfort and reduce energy. Modeling techniques used to simulate naturally ventilation include analytical models, full-scale and small-scale experiments, computational fluid dynamics(CFD) and airflow network tools, which have advantages and limitations. Investigations on atrium structure and opening characteristics have been limited up to now. This thesis studies the temperature stratification and air flow rates inside atrium buildings in purely buoyancy-driven ventilation. Ventilation effects in models with different heat sources, opening locations, opening sizes and numbers of floors are compared using CFD simulations. An airflow network tool, CoolVent, is used to compare the results with CFD models. Both temperatures and flow rates match well with discrepancies less than 10%. Therefore, the well-mixed temperature assumption in the atrium in the airflow network tool is suitable for single-layer atrium buildings. The full-scale experiment provides a detailed data set for further investigations. Air temperatures keep stable on every floor but increase with height. Therefore, the well-mixed temperature assumption over the entire height of the atrium in many analytical models is not applicable when the cross section of the atrium is small. The prediction of temperature distribution and flow rates in atrium buildings with buoyancy-driven ventilation is provided in details. Indoor air temperatures and flow rates can be calculated with known outside air temperatures and surface temperatures in the atrium. The estimation of heat transfer coefficients, especially the approximation of stairs can cause some discrepancies between calculated and actual results. Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2018.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 97-99).

Comparative urban performance simulation

2022-01-13T07:53:53Z

Comparative urban performance simulation Farrell, Robert James, III This research is concerned with applying environmental urban performance analysis methods to comparative urban master planning. Using bottom-up physics-based urban simulation algorithms, the author established a repeatable methodology for computationally analyzing and comparing urban environments. Conditions simulated included, individual building operational energy use, floor-by-floor spatial daylight autonomy, and site wide occupant mobility. The study area is the Interstate 195 redevelopment site in Providence, Rhode Island. Four historic master planning documents were sampled from 1992 to 2012. The predominate instrument for geometric modeling and simulation was the MIT Urban Modeling Interface(UMI). The methodology proposed in this study provides both, a specific framework of values for performance optimization in Providence as well as a more general framework for the automation of urban simulations in disparate regions. Results from this experiment were processed using custom instrumentation, built using web-based network architecture, to provide rapid result visualization and interactive urban data display. The research concludes by proposing a new architecture of urban system modeling. Thesis: S.M. in Architecture Studies, Massachusetts Institute of Technology, Department of Architecture, 2017.; Cataloged from PDF version of thesis.; Includes bibliographical references.

Biologically-inspired high-performance envelope design in tropical climates

2022-01-13T07:53:53Z

Biologically-inspired high-performance envelope design in tropical climates McCormick, Elizabeth L. (Elizabeth Lister) Removed from bioclimatic design and vernacular styles, modern buildings have become merely icons, symbolic of humankind's victory over nature - evident in the rapid escalation of global greenhouse gas emissions and fossil fuel consumption. As tropical regions face unprecedented growth, this thesis looks to the physiological adaptations of tropical plants to identify fac̦ade design strategies that reduce or eliminate the need for air conditioning in hot-humid regions. Using the dynamic stressors of tropical climates as a source of inspiration, this work hypothesizes that the abundant latent energy found in tropical climates can be used to power discernable thermal change in unconditioned spaces. Using environmental cues to trigger non-linear events, plants can change observable characteristics in response to even small changes in external stimuli. This research questions how extreme differentials at the façade can promote change in interior environments. Using infrared photography to understand the thermal response of tropical plants under environmental stress plus an extensive review of plant physiology, this thesis explores space, variability and storage, as strategies for building enclosure systems. Given the innate ability of porous materials to change characteristics in different environments, materials are manipulated to control directional vapor drive in ways that benefit interior thermal comfort. To explore the hygrothermal behavior of potential enclosure materials and assemblies, the author designed and constructed a custom tabletop hotbox, which is easily and affordably replicated. Through extensive testing and biological translation, the result is a repeatable method of exploring natural phenomena and choreographing moisture drive in building materials, as inspired by plant biology. Thesis: S.M. in Architecture Studies, Massachusetts Institute of Technology, Department of Architecture, 2017.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 105-108).

Free4orm framing : high-performance bending-active strip construction

2022-01-13T07:53:53Z

Free4orm framing : high-performance bending-active strip construction Aeck, Richard Hull This thesis re-thinks conventional light frame and panelized construction methodologies employed in residential and general medium-scale construction. To do so, it investigates the flexural geometry, the structural performance, and volumetric approaches to systematizing elastically bent developable strips. Many rapidly-renewable sheet materials exist or are near market, and the local availability of flatbed machining increases with each new makerspace. Thus, this thesis proposes using simple cutting and bending operations, site-applied attachments, and granulated insulation to produce permanent, freeform, stressed-skin formwork (which is herein branded "Free4orm" strip construction). Observing only partial engagement of medium-scale building applications, this project deploys elastic bending for design diversity by developing open, pre-cut, site-assembled systems for complex structural form. Initial contextual, typological, and geometric research exercises lead to an experimental installation (fiber-reinforced polymer rod and shrink-wrap), to material testing (plywood, bamboo, and phenolic paper), and then to creating computational dimensional analysis tools. Different methods of assembling (tiling, hinging, linking, networking, self-straining, wrapping, staggering etc.) and "unitizing" bending-active strips are developed, tested, and ultimately combined into a prototype, "bend-up, zip-up, iron-up," methodology. Numerical solvers and plug-ins (Strand7, Karamba, and Scan&Solve) are used for in-process analysis to inform conceptualization and to supplement theoretical predictions. Full-scale prototype "unitized, rapid-assembly" and "semiunitized, site-assembly" specimens are fabricated and experimentally loaded to evaluate theoretical stress predictions and preliminary detailing. In the closing design exercises and demonstrations, a single-module arch and a heliotropic canopy are presented. This project explores different possibilities for using flexure to create cost-aware dimensional variation in residential building systems in order to enable passive functional articulation and increase access to surface-active architecture. Thesis: S.M. in Architecture Studies, Massachusetts Institute of Technology, Department of Architecture, 2017.; Cataloged from PDF version of thesis. "February 2017."; Includes bibliographical references (pages 127-131).

Modeling urban energy supply schemes

2022-01-13T07:53:53Z

Modeling urban energy supply schemes Tran, Bradley J Rapid urbanization places increased pressure on governments and cities to use economical, low-carbon energy supply strategies. This manuscript details efforts to develop an integrated energy supply and demand analysis tool to help urban planners and designers evaluate and compare schemes to satisfy the electric, heating, and cooling demands of urban areas. Current simulation tools tend to focus on either the demand- or supply-side aspect of the energy challenges cities face. Additionally, these tools are often overly simplistic or complex with steep learning curves, rendering analyses directionally incorrect or inaccessible. The developed framework integrates a 3D modeling platform, an industry-standard energy simulation engine, and variable-efficiency supply models to increase the accessibility and usability of results. This will help municipalities, developers, and urban planners make informed decisions related to energy supply schemes at the neighborhood level regarding estimated energy consumption, carbon emissions, and energy costs. The approach is applied to case studies from six mixed-use neighborhood designs in three cities: Boston, Lisbon, and Kuwait City. The results illustrate the significance of using load- and temperature-dependent supply models instead of constant COP models. The results underscore the influence that weather, equipment, and regional power generation characteristics have on the optimal energy supply strategy for a given neighborhood design. Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2017.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 23-25).

Low carbon pathways for structural design : embodied life cycle impacts of building structures

2022-01-13T07:53:53Z

Low carbon pathways for structural design : embodied life cycle impacts of building structures De Wolf, Catherine (Catherine Elvire Lieve) Whole life cycle emissions of buildings include not only operational carbon due to their use phase, but also embodied carbon due to the rest of their life cycle: material extraction, transport to the site, construction, and demolition. With ongoing population growth and increasing urbanization, decreasing immediate and irreversible embodied carbon emissions is imperative. With feedback from a wide range of stakeholders - architects, structural engineers, policy makers, rating-scheme developers, this research presents an integrated assessment approach to compare embodied life cycle impacts of building structures. Existing literature indicates that there is an urgent need for benchmarking the embodied carbon of building structures. To remediate this, a rigorous and transparent methodology is presented on multiple scales. On the material scale, a comparative analysis defines reliable Embodied Carbon Coefficients (ECC, expressed in kgCO2e/kg) for the structural materials concrete, steel, and timber. On the structural scale, data analysis evaluates the Structural Material Quantities (SMQ, expressed in kg/m²) and the embodied carbon for existing building structures (expressed in kgCO2e/m²). An interactive database of building projects is created in close collaboration with leading structural design firms worldwide. Results show that typical buildings range between 200 and 550 kgCO2e/m² on average, but these results can vary widely dependent on structural systems, height, size, etc. On the urban scale, an urban modeling method to simulate the embodied carbon of neighborhoods is proposed and applied to a Middle Eastern case study. A series of extreme low carbon case studies are analyzed. Results demonstrate that a novel design approach can lead to buildings with an embodied carbon as low as 30 kgCO2e/m² which is an order of magnitude lower than conventional building structures today. Two pathways are implemented to lower the embodied carbon of structures: choosing low carbon materials (low ECC) and optimizing the structural efficiency of buildings (low SMQ). This research recommends new pathways for low carbon structural design, crucial for lowering carbon emissions in the built environment. Thesis: Ph. D. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2017.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 151-174).

Building archetype calibration for effective urban building energy modeling

2022-01-13T07:53:53Z

Building archetype calibration for effective urban building energy modeling Cerezo Davila, Carlos In response to the current environmental challenges, city governments worldwide are developing action plans to both reduce GHG emissions and increase the resilience of their built environment. Given the relevance of energy use in buildings, such plans introduce a variety of efficiency and supply planning strategies ranging from the scale of buildings, to full districts. Their implementation requires information about current building energy demands, and how these demands, and the city's energy ecosystem at large, may change as a result of a specific urban intervention. Unfortunately, metered data is not available at a sufficient level of detail, and cities face an "information gap" between the aggregate scale of their emission targets, and the scale of implementation of energy strategies. To close it, municipalities and other interested stakeholders require modeling tools that provide accurate spatially and temporally defined energy demands by building. Urban Building Energy Models (UBEMs) have been proposed in research as a bottom-up, physics based, urban modeling technique, to estimate energy demands by building for current conditions and future scenarios. Given the large number of data inputs required in their generation, UBEMs have relied on their characterization through "building archetypes". Yet, in the absence of detailed building and energy data, this process has remained somewhat arbitrary, relying on deterministic assumptions and the subjective judgement of the modeler. The resulting simplification can potentially lead to predictions that misrepresent urban demands and misinform decision makers. In order to address these limitations and enable the large scale application of UBEMs, this dissertation introduces a set of modeling and calibration techniques. First, in order to demonstrate the feasibility of citywide municipal UBEMs, an 80,000 buildings model is generated and simulated for the city of Boston, based exclusively on currently available and maintained municipal datasets. An automated modeling workflow and a new library file format for archetypes are developed for that purpose, and current limitations of municipal datasets and practices are identified. To improve the reliability of UBEMs in reproducing metered demands, a new calibration approach is proposed, which applies principles of Bayesian statistics to reduce the uncertainty in archetype parameters defined stochastically based on a sample of metered buildings. The method is demonstrated and validated in the model of a residential district in Kuwait with 323 annually metered buildings, showing errors below 5% in the mean and 15% in the variance when compared with the measured EUI distribution. The accuracy of the resulting UBEM when reproducing EUI distributions is also compared with typical deterministic approaches, resulting in an error improvement of 30-40%. The method is expanded for its application when monthly energy data is available, and applied for the calibration of a sample including 2,662 residential buildings in Cambridge, MA. Finally, the relevance of calibrated archetype-based UBEMs in urban decisions is discussed from the perspectives of policy makers, energy providers, urban designers and real estate owners in two application cases in neighborhoods of Kuwait City and Boston. Thesis: Ph. D. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2017.; Cataloged from PDF version of thesis. Page 156 blank.; Includes bibliographical references (pages 143-152).

Validated interactive daylighting analysis for architectural design

2022-01-13T07:53:53Z

Validated interactive daylighting analysis for architectural design Jones, Nathaniel Louis The conventional approach to predicting interior illumination and visual discomfort in buildings is to run a ray tracing simulation with high accuracy settings, wait while the simulation processes, and repeat as necessary with modifications to the scene and settings. This workflow lacks interactivity and usually occurs late in the design process to validate a completed design, if at all. For architecture to benefit from daylight as a practical, glare-free alternative to electric lighting, daylighting simulation and visual discomfort predictions must be available in real time during design. This thesis describes three innovations towards this goal: development of a parallel ray-tracing engine, validation against high dynamic range (HDR) photography and annual simulations, and human subject tests with interactive progressive rendering. Lighting simulation can be sped up more than an order of magnitude by running it in parallel on readily available graphics processing units (GPUs). Accelerad is a GPU-accelerated version of RADIANCE synthetic imaging software for global illumination simulation developed by the author, introducing a novel method for parallel multiple-bounce irradiance caching. In validation studies comparing simulated and measured luminance and visual discomfort, Accelerad achieves similar accuracy to RADIANCE at a speedup of 16 to 44 times. Applied to annual simulation methods to calculate climate based daylighting metrics such as daylight autonomy and annual sun exposure, Accelerad is 10 times faster than DAYSIM and 25 times faster than the five-phase method. Additionally, a progressive path tracing option is explored that calculates glare probability in seconds and enables interactive visual discomfort simulation. By providing accurate lighting simulation results to designers in real time, this information is expected to inform the design process in ways not previously possible. In human subject tests, the availability of realtime feedback was associated with increased exploration of the design space, higher confidence in proposed designs, higher satisfaction with the design task, and better performing designs with respect to daylight autonomy and daylight glare probability. This supports the theory that system response time affects users' cognitive states and suggests that designers will be more likely to adopt building performance simulation tools if they produce reliable results at interactive speeds. Thesis: Ph. D. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2017.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 139-152).

Structural grid shell design with Islamic pattern topologies

2022-01-13T07:53:53Z

Structural grid shell design with Islamic pattern topologies Khouri, Noor K Geometric patterns, pioneered centuries ago as a dominant form of ornamentation in Islamic architecture, represent an abundant source of possible topologies and geometries that can be explored in the preliminary design of discrete structures. This diverse design space motivates the coupling between Islamic patterns and the form finding of funicular grid shells for which structural performance is highly affected by topology and geometry. This thesis examines one such pattern through a parametric, performance-driven framework in the context of conceptual design, when many alternatives are being considered. Form finding is conducted via the force density method, which is augmented with the addition of a force density optimization loop to enable grid shell height selection. A further modification allows for force densities to be scaled according to the initial member lengths, introducing sensitivity to pattern geometry in the final form-found structures. The results attest to the viable synergy between architectural and structural objectives through grid shells that perform as well as, or better than, quadrilateral grid shells. Historic and cultural patterns therefore present design opportunities that both expand the conventional grid shell design vocabulary and offer designers an alternative means of referencing vernacular traditions in the modern built environment, through a structural engineering lens. Key words: grid shell, structural topology, Islamic pattern, parametric design, performance driven design, force density method, form finding. Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2017.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 81-84).

Machine learning paradigms for building energy performance simulations

2022-01-13T07:53:53Z

Machine learning paradigms for building energy performance simulations Aijazi, Arfa N. (Arfa Nawal) This research seeks to overcome a technical limitation of building energy performance simulations, the computation time, by using surrogate modeling, a class of supervised machine learning techniques where the output is a performance metric. Though early machine learning methods were introduced decades ago, the convergence of computation power, more data collection, and maturation of methods has led to an explosion in the types of problems machine learning can be applied to. A comparison of several common surrogate modeling techniques found that parametric radial basis functions and Kriging are highly accurate regression techniques for predicting building energy consumption. For a single climate, these regression techniques can predict the total energy consumption to within 2% of a detailed energy simulation, but in a fraction of a second, about five orders of magnitude faster. Integrating a Kriging surrogate model with multi-objective optimization, allowed for finding retrofit recommendations in Lisbon that are cost effective and can reduce the present-day energy consumption of an existing apartment by up to 20%. Similarly, integrating surrogate model with multi-objective optimization can find retrofit options in Boston that can reduce the present-day energy consumption and unmet hours in the future. Combined this body of works strives to add value to existing building energy performance simulation tools as more than just an exercise for code compliance but as a real design tool that can guide decision making. Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2017.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 134-138).

C L I M A + : an early design natural ventilation prediction method

2022-01-13T07:53:53Z

C L I M A + : an early design natural ventilation prediction method Arsano, Alpha Yacob One of the most widely discussed passive building design strategies is using natural ventilation for cooling. In addition to providing fresh air, which enhances occupant productivity and comfort, strategic implementation of natural ventilation in buildings reduces the energy needed for cooling. And this reduction in energy consumption significantly reduces carbon dioxide emissions. During the initial design phase, designers routinely use climate-file based analysis to evaluate the potential for comfort ventilation against other passive building strategies. Following this initial screening, it is customary to conduct detailed simulations to further develop design ideas. At this point, inconsistencies can arise between the early climate-file based analysis and later-stage simulations. Major differences arise from limitations of climate-file based analysis to account for influences of construction assemblies, building program, and occupant comfort preferences. This manuscript presents a building performance-based climate analysis method where quick, single-zone simulations are run in EnergyPlus. The ventilation cooling potential for a site and a building program is calculated using a series of Python scripts. Thesis: S.M. in Architecture Studies, Massachusetts Institute of Technology, Department of Architecture, 2017.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis. "June 2017."; Includes bibliographical references (pages 64-65).

Improvisational specification of design spaces

2022-01-13T07:54:01Z

Improvisational specification of design spaces Charidis, Alexandros As a mathematical abstraction and as a model for automated problem solving, the classical notion of a design space has proven convenient for the sciences and the engineering disciplines over the past sixty years. This is also true for models of calculating in design. These models, however, assume implicitly that a design space, one of possible compositions of shapes, is invented as a one-off final description or specification of designs, and that the individual who designs or composes has nothing new to contribute in the calculations other than to search and select among available possibilities. I suggest that this is limiting for the visual fields, such as architecture and applied arts. In this thesis, I articulate a novel, improvisational theory of design spaces. I describe a model of calculating an improvisational specification that complements the proposed theory and reconciles classical analytical approaches with the open-ended creative practice of improvisation. The proposed specification is based on the shape grammar formalism and the associated algebras of shapes due to their unique treatment of shapes as raw, unanalyzed pictorial entities. The model is made of two calculating procedures: a. compositional rules are applied on shapes and their parts distinguished in observation, b. backwards descriptive rules specify the composition in terms of topological decompositions of shapes. Improvisation moves forward through compositional rules applied perceptually on shapes, while the design space in which composition happens is specified backwards by studying how shape decompositions map continuously from one rule application to another. I describe the differences between the proposed improvisational specification and classical specifications, which are defined in terms of symbols rather than spatial, pictorial entities. I outline important extensions to the proposed formalism and conclude by proposing improvisation as an alternative umbrella concept that presents opportunities to expand classical conceptualizations of design spaces from exclusive engagement with analysis as a form of preliminary projection of results before calculating. Thesis: S.M. in Architecture Studies, Massachusetts Institute of Technology, Department of Architecture, 2017.; Thesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2017.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 93-97).

The Roman Pantheon : scale-model collapse analyses

2022-01-13T07:53:53Z

The Roman Pantheon : scale-model collapse analyses Plunkett, J. William (James William, Jr.) The Roman Pantheon is among the largest unreinforced masonry dome ever built and is an unparalleled example of the construction capabilities of the ancient Romans. As one of the most well-known buildings in the world, its preservation remains important because of its cultural and societal significance, and the methods used to assess the safety of historic masonry structures continue to be developed, particularly for three-dimensional vaulted forms. Through a study of the Roman Pantheon, this thesis compares analytical and experimental results on a 1:100 scale model of the variable thickness, hemispherical dome. The model is created using additive manufacturing for accuracy. This thesis, using a physical scale model, quantifies the safety of the Roman Pantheon against the two most probable causes of collapse (i) deformation of the building geometry and (2) seismic activity. The structural behavior of the model is compared to analytical predictions of (1) spreading supports, simulating leaning walls that result from the dome thrust or settling of the foundations, and (2) tilting, a first-order approximation of horizontal ground acceleration. The experimental tests lead to the formation of a mechanism and collapse due to instability. High-speed imagery captures the observed collapse mechanisms and failure limits. Experimental results are compared to analytical predictions for hemispherical masonry domes. The results of the physical experiment demonstrate the potential for digitally fabricated scale models in approximating the behavior of three-dimensional structures with complex geometries. The low cost and rapid approach provides a useful method for validating analytical predictions of the limit states and collapse mechanisms of unreinforced masonry structures. Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2016.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 27-31).

Modeling and characterizing bi-directional airflow in natural ventilation

2021-07-05T14:03:20Z

Modeling and characterizing bi-directional airflow in natural ventilation Zhang, Qin, Ph.D. Massachusetts Institute of Technology Bi-directional airflow in natural ventilation is an essential but not-well-understood scenario due to the complexity of airflow patterns as well as the strong coupling effect between temperature and ventilation. Neglecting bi-directional natural ventilation will result in problematic solutions and inaccuracy in estimation of ventilation performance. This work is focused on filling the knowledge gap by understanding the bi-directional airflow using computational fluid dynamics (CFD). Two important scenarios are simulated and analyzed: 1. Two-zone model with pure buoyancy forces, 2. Multi-zone model with combined wind and buoyancy forces. In the 1st model, a new concept of "local discharge coefficient" is proposed for its consistency under different boundary conditions. The influence of radiative heat transfer on simulation accuracy and ventilation performance is also investigated. In the 2nd model, the transient behaviors of airflow and the dynamics of wind and buoyant forces are analyzed and characterized. A new physical model is proposed based on simplified assumptions and nondimensionalization. This model is able to predicting the transient behavior of multi-zonal ventilation that involves bidirectional airflow patterns. The result of this study is to be integrated in CoolVent, the software designed by Building Technology Lab. Thesis: S.M., Massachusetts Institute of Technology, Department of Architecture, 2016.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 98-105).

From sink to stock : the potential for recycling materials from the existing built environment

2022-01-13T07:53:53Z

From sink to stock : the potential for recycling materials from the existing built environment Turan, Irmak İfakat This thesis examines the prospect for new local recycling schemes for concrete and masonry waste within an existing urban environment. Using Lisbon, Portugal as a case study, I propose three context-specific material recycling scenarios to make use of mineral construction waste generated as city's aging residential building stock is replaced over the next 30 years. The objective of the work is to explore whether the existing stock, as it is overturned, can feed the future built environment and to what degree. What happens to construction waste when obsolete buildings are demolished? In the case of Lisbon, most of it is used as backfill or disposed in landfill. Little of the mineral waste's material value is recovered. Nonetheless, the urban built environment maintains the alluring prospect of being a source for our impending resource needs. The concept of urban mining and the circular economy movement bolster this proposition as a path towards more efficient, localized resource use within cities. I compare the three recycling proposals, along with standard landfill disposal, in terms of greenhouse gas emissions, land use, and cost. The results show that from both an environmental and economic standpoint, recycling is not always the optimal solution. The impacts depend not only on the recycling processes and end uses, but also the avoided and added burdens consequent to changes in the existing system. Through this analysis, I identify both the limiting factors and potential opportunities for improvement in the current paradigm of material use and reuse in construction, in Lisbon and beyond. Thesis: S.M., Massachusetts Institute of Technology, Department of Architecture, 2016.; "June 2016." Cataloged from PDF version of thesis.; Includes bibliographical references (pages 88-93).

One size does not fit all : innovation in emergency housing with a focus on Nepal 2015

2022-01-13T07:53:53Z

One size does not fit all : innovation in emergency housing with a focus on Nepal 2015 Voros, Jamie L Abstract Every year millions of people are displaced due to natural disasters and very primitive transitional shelters, or 't-shelters', exist to provide semi-permanent housing. Many t-shelter designs do not cater to all the needs of their inhabitants and are only functional in the short term, often leaving many people relying on t-shelters for housing in an unsafe and unsanitary environment. This thesis addresses the problem of people needing housing and of unsafe transitional housing by presenting a new design process and ultimately a t-shelter design specifically for the victims of the 2015 earthquakes in Nepal in the Kathmandu area. The process involves three key elements; identifying the specific needs of the displaced people, analyzing what materials and labor are available and ensuring that the shelter will be used as intended and therefore remain safe. The resulting shelter design harnesses the structural strength of the geodesic dome, the simplicity of reciprocal joinery and strong yet lightweight nature of bamboo. The effectiveness of the proposed new design process is demonstrated through checking the resulting shelter design meeting measurable outcomes like cost, structural integrity and skill level required to construct. Thesis: S.B., Massachusetts Institute of Technology, Department of Architecture, 2016.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 71-72).

Urban building energy modeling and retrofit design as a means to inform effective public policy : Boston case study

2025-12-05T13:17:35Z

Urban building energy modeling and retrofit design as a means to inform effective public policy : Boston case study Irani, Ali(Architect), Massachusetts Institute of Technology Residential buildings use upwards of 20% of the total energy consumed annually in the United States. This, coupled with the desire to reduce overall utility costs and improve occupant comfort on the part of residents, places cities, as the main catalyst for local energy policy, at the forefront of the drive for a more sustainable built environment. This thesis seeks to explore the potential savings associated with energy retrofits in selected neighborhoods in the city of Boston, by developing a comprehensive urban energy model and implementing two retrofit strategies. As part of the methodology, this thesis will combine GIS data with building construction, use, and equipment data to develop a quick, accurate, and adaptable energy simulation model. By combining the findings of the simulation with socio-economic indicators such as income level and ownership type, this thesis will examine how to best implement the selected building retrofit strategies. Of particular interest, is the idea of an annual adoption rate for a particular strategy and the perceived effects of socio-economic indicators on the actual adoption. Ultimately, the findings of this thesis will enable a thoughtful discussion of the effective implementation of public policy and serve as a guide for further investigations focusing on the demographics of urban energy use. Thesis: S.B., Massachusetts Institute of Technology, Department of Architecture, 2016.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 41-42).

Illuminating education : composition and use of lighting in public K-12 classrooms

2022-01-13T07:53:53Z

Illuminating education : composition and use of lighting in public K-12 classrooms Ballina, Mariana Despite ample research on light's effect on the human body (and particularly its effect on student and teacher health and performance), understanding of light's role in operational energy consumption, and advancement made in architectural design to address these impacts, little is known about actual use patterns and occupant exposure to light in classroom settings. Through the measurement of lighting conditions and an examination of occupant behavior under both electric and natural lighting systems in K- 12 schools of Southern California, this research aims to bridge gaps between knowledge of light's impact on the human body and results of human exposure to various light as well as our understanding of occupant use and the current architectural design of schools. An analysis of illuminance and color temperature measurements across 21 classrooms, observations, and questionnaire responses from 27 teachers reveals muted daylight availability and low and warm color electric lighting conditions in the classroom that consistently falls below recommended illuminance and light levels, as well as lighting controls, installations, and design that may not allow for adequate control within these rooms by occupants. The work presented informs future design choices and assumptions made by architects of K- 12 schools, and may provide context for research on and estimates of light's biological impact on students. Thesis: S.B., Massachusetts Institute of Technology, Department of Architecture, 2016.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 101-102).

Improving the use of commercial building HVAC systems for electric grid ancillary services

2022-01-13T07:53:53Z

Improving the use of commercial building HVAC systems for electric grid ancillary services Blum, David H. (David Henry) Increasing renewable and distributed electricity generation increases the requirement of grid-scale flexibility, often provided through ancillary services. Buildings can play a significant role in meeting this challenge by providing ancillary services with their HVAC systems. However, use of commercial HVAC systems in this way comes with significant challenges, which relate to interactions between the HVAC system and building operation, electricity markets, and electric grid operators. This thesis addresses these challenges through the use of dynamic modeling, model predictive control, and energy storage scaling techniques. First, a model of a representative VAV system is built using Modelica and simulated to characterize the system's performance while providing reserve and regulation ancillary services. It is found that reserves are provided most effectively when airflow is reduced through the terminal units, while regulation is provided most effectively when power-consuming equipment is directly controlled and has little effect on occupancy service. Next, a novel 24-hour HVAC MPC optimization problem is formulated and solved that separately accounts for a building's reserve and regulation revenue from electricity markets. Over a three-day period, it is found that ancillary service revenue can make up for 67% of HVAC energy costs when considering wholesale energy prices, and 18% when considering retail energy prices and market rules that disallow overlapping regulation and reserve capacity offerings. Second, an MPC control approach is used for the determination of opportunity costs associated with HVAC ancillary service provision, which are comparable to those of generators and could be bid into ancillary service markets. A method is developed to these costs and it is found that they can exceed $66/MWh if considering wholesale energy prices, and $93/MWh if considering retail electricity prices. Lastly, energy and power densities and costs for three thermal storage technologies available to commercial buildings are produced and compared to those of batteries. In addition, a method is developed to estimate the building HVAC reserve capacity within neighborhoods without the need for sophisticated energy simulations. In a case study involving 172 buildings, it is estimated that approximately 1100 kWh of peak hourly reserve capacity is available if thermostat setpoints are changed by 2°C. Thesis: Ph. D. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2016.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 135-145).

Multi-objective optimization for the conceptual design of structures

2022-01-13T07:53:53Z

Multi-objective optimization for the conceptual design of structures Brown, Nathan C. (Nathan Collin) Using computational tools, fast and accurate predictions of building performance are increasingly possible. In parallel, the expectations of a high-performance building have been rising in contemporary architecture, as designers must synthesize many inputs to arrive at a design that fulfills a wide range of requirements. Despite the clear need for assistance in prioritizing and managing different design objectives, advances in performance analysis have not commonly translated into guidance in early stage design, as the limits of the traditional design process and a separation of disciplines have relegated performance feedback to later phases. In order to facilitate better design on a holistic level, researchers in related areas have developed multiobjective optimization (MOO), which is a methodology intended for navigating complex design spaces while managing and prioritizing multiple objectives. However, after reviewing existing design optimization research and considering current usage of optimization in AEC practice, a number of clear research questions arise: How can conceptual, architectural design problems be formulated and solved using MOO in a way that generates diverse, high-performing solutions? What is the best way for the designers of buildings and structures to interact with MOO problems? Finally, how does the use of MOO in the conceptual phase affect design possibilities and outcomes? This thesis addresses these key research questions, along with a number of secondary questions, through a combination of design case studies, tool development, user experience testing, and historical analysis. First, it presents a conceptual framework for implementing MOO within architectural parametric design tools in flexible, interactive way. Next, it shows the outcomes of a conceptual design exercise in which participants are given increasing access to performance feedback. Finally, through the application of MOO to three long span roof case studies, it demonstrates how MOO can lead to diverse, high-performing results that are difficult to generate through other means, before introducing a new way in which multi-objective techniques can be used to analyze historical structures. Together, these contributions encourage more widespread and effective use of multi-objective optimization in conceptual design, leading to better performing buildings and structures without overly constraining creative, innovative designers. Key words: multi-objective optimization, design space exploration, conceptual design, design tradeoffs, interactive design tools, structural design, embodied and operational energy. Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2016.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 107-113).

Decoding details : integrating physics of assembly in discrete element structures

2022-01-13T07:53:53Z

Decoding details : integrating physics of assembly in discrete element structures Ariza, Inés S.M. Massachusetts Institute of Technology Architecture is intrinsically the coordination of parts to form a whole, and the detail is the critical point where this coordination is resolved. Between technical and perceptual constraints, details are geometrical solutions and organizational devices that negotiate physics, construction, assembly, materials, fabrication, economy, and aesthetics, all at once. Over centuries, detail formulas have been created, tested and revised by builders, architects, engineers and fabricators; collected in catalogs and magazines, they have been usually documented in two-dimensional sections that silence all intervening forces. While masters with knowledge in construction and materials are able to iterate through different possibilities creating novel details, usually less experienced designers can only reproduce standard solutions. In the era of digital design and fabrication, where material and building information can be parametrically linked and massively computed, can we challenge what we can build with a new way of looking at details? This thesis introduces the concept of synced detailing, where conflicting constraints are resolved in the details. As a case study, stability and assemblability are studied on a structurally challenging discretized funicular funnel shell. The goal is to eliminate scaffolding during assembly using only joint details. Finite element (FE) analysis is performed at every step of the assembly sequence to show global and local instability. Local translation freedom (LTF) analysis shows the range of feasible assembly directions. Detailing knowledge is studied and encoded in shape rules to create a detail grammar. Real time visual feedback of the constraints informs the designer to apply these rules to create joints that satisfy across a range of priorities. This method is generalizable for other constraints, allowing architects to create novel solutions informed by quantifiable analysis and encoded knowledge. Keywords: details, discrete element structures, assembly, funnel shell, digital fabrication. Thesis: S.M., Massachusetts Institute of Technology, Department of Architecture, 2016.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 69-71).

Procedures for automated building energy model production for urban and early design

2022-01-13T07:53:53Z

Procedures for automated building energy model production for urban and early design Dogan, Timur This research is meant to facilitate a wider use of energy simulation in urban and schematic building design. The major contribution is the development and validation of software algorithms that can manage, automatically produce and execute building energy models for urban and schematic design. Modeling approaches for building performance simulation engines such as EnergyPlus and TRNSYS have been developed. The first approach introduces an algorithm that automatically converts arbitrary building massing models into multi-zone thermal models following the ASHRAE 90.1 Appendix G prescribed perimeter and core discretization schema. This method yields geometrically resolved multizone models and provides a streamlined workflow for single and multi-building energy evaluation. The second approach dissects an urban massing model that may consist of hundreds of buildings with various architectural programs into a discrete number of "typical room" energy models. It is shown that for standard interior partitions and fully conditioned spaces the method yields results that are comparable to conventional perimeter and core simulations in terms of accuracy as well as temporal and spatial resolution at a fraction of the calculation time. This speed-up facilitates interactive urban level design evaluations. The third approach explores the energetic consequences of using a zoning methodology that goes beyond generic perimeter and core subdivisions. Based on a review and categorization of real floor plan designs it is shown that key characteristics of interior subdivisions have a decisive effect on building energy use and present a largely untapped opportunity for architects to reduce building energy use in schematic design. Each approach is documented and simulation results are compared against conventional modeling workflows for a realworld urban case study. As a proof of concept, the mentioned methods have been implemented as plug-ins for the widely used CAD modeling software Rhinoceros3d (Rhino) and its parametric scripting environment Grasshopper. Thesis: Ph. D. in Architecture: Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2015.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 103-109).

Integrating interactive evolutionary exploration and parametric structural design

2022-01-13T07:53:59Z

Integrating interactive evolutionary exploration and parametric structural design Danhaive, Renaud Aleis Pierre Emile Current modeling and analysis tools are extremely powerful and allow one to generate and analyze virtually any structural shape. However, most of them do not allow designers to integrate structural performance as an objective during conceptual design. As structural performance is highly linked to architectural geometry, there is a need for computational strategies allowing for performance-oriented structural design in architecture. In order to address these issues, this research combines interactive evolutionary optimization and parametric modeling to develop a new computational strategy for creative and high-performance conceptual structural design. Parametric modeling allows for quick exploration of complex geometries and can be combined with analysis and optimization algorithms for performance-driven design. However, this methodology often questions the designer's authorship as it is based on the use of black-box optimizers. On the other hand, interactive evolutionary optimization empowers the user by acknowledging his or her input as fundamental and includes it in the evolutionary optimization process. This approach aims at improving the structural performance of a concept without limiting the creative freedom of designers. Taking advantage of the two frameworks, this research implements an interactive evolutionary structural optimization framework in the widely used parametric modeling environment constituted by Rhinoceros and Grasshopper. Previous work has illustrated the benefits of combining parametric modeling and genetic algorithms for design space exploration. Comparatively, the implemented design tool capitalizes on Grasshopper's versatility for geometry generation but supplements the visual programming interface with a flexible portal increasing the designer's creative freedom through enhanced interactivity. The tool can accommodate a wide range of structural typologies and geometrical forms in an integrated environment. This research offers a versatile, performance- and user-oriented environment for creative and efficient conceptual structural design. Thesis: M. Eng., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2015.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 47-48).

Demonstration of HVAC chiller control for power grid frequency regulation

2022-01-13T07:53:53Z

Demonstration of HVAC chiller control for power grid frequency regulation Su, Po-An (Po-An Leo) Secondary frequency regulation is a necessary electric grid ancillary service that balances electric power system supply and demand on short time intervals of seconds to minutes. Commercial HVAC chillers may be well positioned to provide secondary frequency regulation as a demand side resource. Commercial 200 ton (703 kWth) chillers serving two buildings in the Boston area are used to experimentally develop a practical closed-loop controller that modifies chiller power demand to provide secondary frequency regulation. In the first setup, a physical controller is connected directly to the chiller and adjusts power through chilled water setpoint. In the second setup, both the chiller and air handling units are controlled through the BAS. Demonstrations using standard electric system operator test routines show the chiller power response to exceed qualification requirements while providing up to +/-25% of chiller nameplate power in secondary frequency regulation capability. The controller is further demonstrated to provide secondary frequency regulation continuously for several hours longer than the standard test routines, during which building cooling load changes significantly. Analysis of results indicate minimum power and variable COP as two factors that could be incorporated into future models to more accurately reflect observed chiller transient behaviour and predict performance. BAS communication delays, ramp rate limits, and compressor cycling are additional factors that can have significant negative impacts on controller performance. Extrapolation of experiment results to higher-level analysis indicates that chillers can contribute to the secondary frequency regulation requirements at the grid level in aggregate, although potential varies greatly depending on climate and building type. There is more potential in the south, where 21% of secondary frequency regulation requirements might be met with chillers; the contribution of chillers in colder climates is minimal. Short-term power balance to achieve stability is essential for the operation of the modern electrical power system. Providing stability through modified control of existing HVAC chillers in commercial buildings is a technologically feasible alternative to existing solutions and can make a meaningful contribution to the electrical grid. Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2015.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 74-77).

Comfort analysis of differences in classroom designs between socioeconomic statuses

2022-01-13T07:53:53Z

Comfort analysis of differences in classroom designs between socioeconomic statuses Coston, Brianna (Brianna Elizabeth) Classroom design has been ever changing, attempting to keep up with the new ideas about education and learning. As we learn more and more about how children learn, we adapt our learning styles with this new knowledge. Architecture is something that is meant to last for a while since construction costs of buildings are so expensive. Because our buildings are changing slower than our learning styles, we are currently having to spend large amounts of money on retrofits to buildings that aren't the best fit. This thesis is a look into the history behind how schools have changed in America and an analysis of a few schools in San Diego that are stuck thirty years behind the times. It takes the pros and cons of these schools and proposes a new way to look at school design for the future. Thesis: S.B., Massachusetts Institute of Technology, Department of Architecture, 2015.; Cataloged from PDF version of thesis.; Includes bibliographical references (page 39).

Towards comfortable and walkable cities : spatially resolved outdoor thermal comfort analysis linked to travel survey-based human activity schedules

2022-01-13T07:53:53Z

Towards comfortable and walkable cities : spatially resolved outdoor thermal comfort analysis linked to travel survey-based human activity schedules Rakha, Tarek Outdoor thermal comfort can influence human powered mobility choices, namely walking and biking. As more people are living in cities than ever before in human history, the urban environments we erect and populate are unfortunately contributing to phenomena such as climate change, which is negatively affecting urban life. Our understanding and creation of comfortable environments that are conducive to human powered transport can significantly influence carbon emissions, energy efficiency, and human health, as well as have considerable economic and time saving impacts. With the continuous integration of computer-based decision support systems in design processes, there is a need for developing simulation frameworks that aid architects, urban designers and planners in making informed sustainable design decisions. The focus of this work, therefore, is the development of computer tools and workflows that promote the design of walkable and bikeable cities through comfortable outdoor spaces. This dissertation presents firstly, a simulation methodology, verified through a validation experiment conducted on the MIT campus, for spatially and temporally resolved Mean Radiant Temperature (MRT) simulation and consequent outdoor thermal comfort assessment. Secondly, Building Performance Simulation (BPS) occupancy and trip schedules generation through data clustering techniques applied to activity-based travel surveys. An office modeling case study is presented through extracted occupancy scenarios, to compare simulation accuracy against current practice standards. Finally, an assimilation of both workflows is presented to generate "Trip Comfort" metrics for human powered mobility assessment, in the context of existing or newly designed urban structures. Thesis: Ph. D. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2015.; Cataloged from PDF version of thesis.; Includes bibliographical references.

Pan climatic humans : shaping thermal habits in an unconditioned society

2022-01-13T07:53:53Z

Pan climatic humans : shaping thermal habits in an unconditioned society Mackey, Chris (Christopher William) The relationship between people and the thermal environment has a profound impact on lifestyle and culture, influencing what we wear, what spaces we gather around, and how we go about our lives. Yet this relation is often oversimplified in the design of conditioned spaces, assuming occupants have unchanging thermal preferences and no desire to participate in the shaping of a building's microclimates. While we gain a basic satisfaction of thermal need from this simplified view, we lose much by complicating our buildings with HVAC equipment to the point that inhabitants do not understand them, by cellularizing space into bubbles of conditioned air that limit opportunities for continuous communal space, and by having occupants rely on central heating/cooling systems that often require harmful concentrated energy sources, such as fossil fuels. This thesis asks if and how we can design spaces of everyday life that not only satisfy a basic thermal need but also encourage occupant participation in the shaping of microclimates, promote thermally-based social cohesion, and do so using only on passive means. Since the traditional process of evaluating heating/cooling load with an energy model does not hold for unconditioned design, the thesis question requires a new method for exploring design decisions in relation to the thermal environment. Accordingly, research began by developing software to produce high spatial/temporal resolution thermal maps that evaluate design decisions by indicating the parts of a space made warmer or cooler in relation to a seasonal "comfort temperature." With this new means of understanding the thermal environment, several geometric design strategies are tested for two climates - Los Angeles and New York. The tests illustrate that the geometry of a space can have an enormous effect on its thermal habitability once the assumptions of air conditioning and oversimplified occupants are removed. The most powerful of the tested design strategies are used to develop two completely passive urban co-habitation/co-working projects that express and embellish these discovered geometric factors. The designs operate off of a generalizable logic in which the communal, daytime spaces are placed in the areas of a site where they can take advantage of the most powerful and stable thermal strategies while the fringes include less stable, intermittently- occupied, private spaces where occupants can tune the microclimate as they wish. Although this generalizable logic is constant, the two designs illustrate that widely different forms can emerge based on the climate and the tested strategies. Thesis: M. Arch., Massachusetts Institute of Technology, Department of Architecture, 2015.; Thesis: S.M., Massachusetts Institute of Technology, Department of Architecture, 2015.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 144-147).

Daylit density : a simulation-based framework towards performance-aware zoning and real estate development

2022-01-13T07:53:53Z

Daylit density : a simulation-based framework towards performance-aware zoning and real estate development Saratsis, Emmanouil Population growth and related space constraints have led to a planning paradigm that promotes living and working in high-density urban areas. Increasing urban density, however, leads to a conflict between space-use efficiency and access to daylight. To manage this conflict and to ensure sufficient solar access, cities have traditionally relied on zoning guidelines that propose simple, two-dimensional geometric evaluation techniques. This practice seems antiquated in times when computer aided design tools enable architects to test designs before construction. Recent advances in building performance simulation software allow us to compute annual climate-based daylight performance metrics of urban environments accurately, in high spatial resolution and in a timely manner. Given that zoning requirements as well as massing design decisions at the urban planning level may make or break the long-term daylighting potential of a whole neighborhood, the adoption of these tools by zoning boards and planners seems particularly relevant. This manuscript therefore presents a simulation-based framework for formulating more nuanced prescriptive zoning rules, along with a performance-based approach for developers and planners interested in exploring innovative urban massing solutions. The framework is used to evaluate the daylighting performance of common and innovative urban block typologies in New York City. The performance of the investigated massing designs varies; in some cases the designs significantly outperform existing strategies, supporting urban densities that are twice as high as current zoning maxima. Findings are illustrated using a case study and compiled into a set of recommendations for zoning boards, planners and real estate developers towards more sustainable management of solar access at the urban scale. Thesis: S.M., Massachusetts Institute of Technology, Department of Architecture, 2015.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Title as it appears in MIT Commencement Exercises program, June 5, 2015: Daylit Density : a simulation-based framework for performance-aware zoning and real estate development. Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 85-86).

Towards interactive sustainable neighborhood design : combining a tangible user interface with real time building simulations

2022-01-13T07:53:53Z

Towards interactive sustainable neighborhood design : combining a tangible user interface with real time building simulations Rose, Cody M. (Cody McCullough) An increasingly urbanizing human population presents new challenges for urban planners and designers. While the field of urban design tools is expanding, urban development scenarios require the input of multiple stakeholders, each with different outlooks, expertise, requirements, and preconceptions, and good urban design requires communication and compromise as much as it requires effective use of tools. The best tools will facilitate this communication while remaining evidence-based, allowing diverse planning teams to develop high quality, healthy, sustainable urban plans. Presented in this work is a new such urban design tool, implemented as a design "game," created to facilitate collaboration between urban planners, designers, policymakers, citizens, and any other stakeholders in urban development scenarios. Users build a neighborhood or city out of Lego pieces on a plexiglass tabletop, and the system simulates the built design in real time, projecting colors onto the Lego pieces that reflect their performance with respect to three urban performance metrics: operational energy consumption, neighborhood walkability, and building daylighting availability. The system requires little training, allowing novice users to explore the design tradeoffs associated with urban density. The simulation method uses a novel precalculation method to quickly approximate the results of existing, validated simulation tools. The game is presented in the context of a case study that took place at the planning commission of Riyadh, Saudi Arabia in March 2015. Post-game analysis indicates that the precalculation method performs suitable approximations in the Saudi climate, and that users were able to use the interface to improve their neighborhoods' performance with respect to two of the three offered performance metrics. Furthermore, users demonstrated substantial enthusiasm for interactive, tangible, urban design of the sort provided. Improvements to future versions of the design game based on the case study are suggested, but overall, the work presented indicates that collaborative, interactive design tools for diverse stakeholders are an excellent path forward for sustainable design. Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2015.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 73-74).

Urban weather generator user interface development : towards a usable tool for integrating urban heat island effect within urban design process

2022-01-13T07:53:53Z

Urban weather generator user interface development : towards a usable tool for integrating urban heat island effect within urban design process Nakano, Aiko Urban Weather Generator (UWG) is the urban design simulation tool that provides climate-specific advice for cityscape geometry and land use to assist the development of energy-efficient cities that are also thermally comfortable. The software enables urban designers to parametrically test built densities for masterplanning and urban planners to advocate zoning regulations such as building height and land use as well as policies for traffic intensity with energy and thermal implications of these interventions. UWG is the first tool publicly available that incorporates microclimatic considerations in urban design and energy simulations. The project succeeds the work of Bueno et al. (2014) to develop a useful and accessible urban design tool to model urban heat island effect (UHI) from measurements at an operational weather station based on neighborhood-scale energy balances. The sensitivity analyses for Boston, MA, USA, and Punggol, Singapore identify as key parameters the building morphologies such as site coverage ratio and fac̦ade-to-site ratio; building surface albedo and emissivity; and sensible anthropogenic heat in the urban canyon. The consistency of results for these cities reduced required user inputs to the model by 46% without decreasing the simulation accuracy. The developed software is available as a stand-alone tool as well as a new plug-in for the Rhinoceros-based urban modeling interface (umi) to integrate the microclimate analysis in the formal design process. The graphical user interface is written in programming language C# in the Microsoft .NET platform and is available free of charge at http://urbanmicroclimate.scripts.mit.edu/uwg.php. The newly proposed workflow for energy- and thermal comfort-driven urban design and planning is demonstrated through a case study of the new 130 thousand square meter development on the MIT East Campus in Cambridge, MA, USA. An IPCC-based climate change prediction is considered along with UHI to evaluate the proposed massing models at each design phase to ensure thermally comfortable urban development along the way. Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2015.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 125-131).

Analysis and design for thermally autonomous housing in resource-constrained communities : a case study in Bhuj, India

2022-01-13T07:53:53Z

Analysis and design for thermally autonomous housing in resource-constrained communities : a case study in Bhuj, India Gradillas, Madeline S In the 2010 International Workshop on Housing, Health and Climate Change Meeting Report, the World Health Organization identifies housing as a primary cause of poor health in developing countries. The report cites inadequate protection from extreme heat as one of six major concerns for healthy housing environments. As India's population rapidly increases, informal settlements face particular heat risk because of harsh climate conditions, sub-standard building construction and lack of access to electricity for mechanical cooling. There is a need for housing to provide thermal comfort and health by passive means at low cost. Climate specific passive cooling techniques are well known, but are rarely implemented in informal settlements because of density, lack of resources, design integration, and materials availability. This thesis is situated in the practical connection of two normally disparate parts: applied research in passive cooling techniques, and design for development. The work presented results from the establishment of an international co-design partnership between MIT and The Hunnarshala Foundation for Building Technology and Innovations, an NGO based in the hot and arid region of Bhuj, India. It presents data analysis and codesign work that drove the development, field prototyping, and evaluation of appropriate, implementable building solutions to improve thermal conditions in affordable housing in hot and arid climates. New low-cost, multi-layered roof assembly designs are presented and evaluated. Experimental results show that even in severe arid climates the interior conditions can approach ASHRAE and EN 15251 Adaptive Thermal Comfort standards through most of the operating hours. The results of this research will be an important contribution to the designs of the initial phase of the large-scale Rajiv Awas Yojana Slum Free Bhuj re-development housing construction over the next five years in Western India. Thesis: S.M., Massachusetts Institute of Technology, Department of Architecture, 2015.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 154-157).

Improving in place : a passive solar design approach to public housing redevelopment

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Improving in place : a passive solar design approach to public housing redevelopment Geisinger, Jeffrey For the New York City Housing Authority, or NYCHA, sustaining the city's 178,000 units of public housing for future generations is a significant and increasingly difficult task. Faced with aging infrastructure and cuts in federal funding, the city has turned to private sector partnerships for new ways to finance the upkeep of its buildings. The 2013 Land Lease Initiative, NYCHA's unrealized plan to generate funds by renting underutilized open space to residential developers, demonstrated economic potential but overlooked opportunities to repair critical deficiencies in the urban design and energy-efficiency of its public housing developments. This thesis suggests that passive-solar design strategies can influence a more sustainable approach to public housing revitalization, integrating site-sensitive infill development with existing building upgrades. Focusing on the Douglass Houses in the Upper West Side of Manhattan, I analyze how the Land Lease Initiative's high-rise massing would worsen existing buildings' access to natural sunlight, and I suggest an infill development model that preserves solar access to existing facades while connecting the superblocks to the surrounding urban fabric. My research then explores the application of sunspace additions to existing public housing to expand living spaces while simultaneously reducing heating demand. I conclude with a discussion of financial plausibility and large-scale impact on NYCHA's overall housing portfolio. This investigation aims to create an integrated process that links new development and public housing upgrades across site, building, and dwelling scales. Thesis: S.M., Massachusetts Institute of Technology, Department of Architecture, 2015.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 61-63).

New structural systems in small-diameter round timber

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New structural systems in small-diameter round timber Bukauskas, Aurimas (Aurimas M.) Trees, when used as structural elements in their natural, round form, are up to five times stronger than the largest piece of dimensioned lumber they could yield. Additionally, these whole-timbers have a lower effective embodied carbon than any other structural material. When combined into efficient structural configurations and joined using specially-engineered connections, whole-timber has the potential to replace entire steel and concrete structural systems in large-scale buildings, bridges, and infrastructure. Whole-timber may be the most appropriate structural solution for a low-carbon and fully renewable future in both developed temperate regions and the developing Global South. To reduce barriers to adoption, including project complexity and cost, a standardized "kit of parts" in whole-timber is proposed. This thesis proposes new designs for the first and most important element of this kit: a structurally independent column in whole-timber. A 20' compound column in whole-timber is prototyped at full-scale. New, simple calculation methods are developed for estimating the buckling capacity of tapered timbers. Based on conservative assumptions, the embodied carbon of whole-timber column systems is shown to be between 30% and 70% lower than conventional steel systems. Thesis: S.B., Massachusetts Institute of Technology, Department of Architecture, 2015.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (page 51).

Predicting the potential for energy efficiency retrofits in single-family homes : an exploration of data targeting mechanisms

2022-01-13T07:53:53Z

Predicting the potential for energy efficiency retrofits in single-family homes : an exploration of data targeting mechanisms Goldstein, Kaitlin Ryan Historically, the lack of data on the United States' housing stock has been one of the primary barriers to market penetration of residential energy efficiency retrofits. Without knowledge of the homes and customers to reach, outreach has been untargeted and inefficient. As such, a study was performed to determine whether the potential for residential energy efficiency retrofit could be determined in the absence of utility data. The first phase of the research investigated the best pre-retrofit gas consumption metric to predict post-retrofit savings. Energy intensity (weather normalized total gas consumption per square foot) was chosen from four distinct metrics as the best corollary to energy savings. The second phase attempted to predict the pre-usage metric from phase one using only home characteristics and demographics, and the most predictive variables were determined. Data mining techniques were then explored to predict retrofit candidacy using energy intensity as a proxy. After showing that this was difficult to predict even when utility data was available, the progression to the third phase was reconsidered but explored. The models did not perform as expected for three reasons: 1) the marketing variables were not clean/accurate enough 2) the marketing variables did not explain enough of the variance in energy intensity and, 3) the connection between energy intensity and retrofit candidacy was not sufficiently well defined. While a definitive model of retrofit candidacy in the absence of utility data was not found, the research completed offers: 1) a mechanism by which to connect retrofit savings data to homes that have not yet undergone retrofit 2) an in-depth look at using publicly available variables to predict home energy consumption and, 3) a detailed examination of the connection between retrofit potential and raw gas utility data. Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2014.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 90-91).

Structural connections in plywood friction-fit construction

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Structural connections in plywood friction-fit construction Wagner, Mali E. (Mali Esther) CNC mills allow precise fabrication of planar parts with embedded joinery which can be assembled into complex 3D geometries without the use of foreign mechanical fasteners. This thesis studies the behavior of the friction-fit attachment geometries which serve as the sole means of structural connections. The thesis begins by describing the process of converting digital files into physical objects. Next is presented precedents for the use of this system to create both functional and abstract forms, including kits of parts for residential buildings. A review is given of the ongoing research into attachment design optimization and open-source customization, revealing the unanswered question of how the attachments can meet load demands. yourHouse, a full-scale home composed of 3/4" plywood friction-fit parts, is selected as a case study through which the structural performance of the integrated attachments can be analyzed. A series of load tests are performed on the structural connections identified in the house. The function of these connections permits the internal structure and sheathing elements to perform as composite beams for carrying bending. The methodology and expected behavior of the parts are presented, followed by the test results. Next, a discussion and analysis of the data and observations are given to provide first approximations of the system's wind load and gravity load capacity. Finally, recommendations regarding component design, span tables, and the construction method are given with justifications based on the empirical data. Thesis: S.B., Massachusetts Institute of Technology, Department of Architecture, 2014.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 89-90).

Addressing the problem with natural ventilation : producing a guide for designers to integrate natural ventilation into the early stages of building design

2022-01-13T07:53:53Z

Addressing the problem with natural ventilation : producing a guide for designers to integrate natural ventilation into the early stages of building design Fennessy, Kristian (Kristian M.) Currently, the United States alone is responsible for approximately twenty percent of the world's total energy consumption. This consumption is equivalent to roughly 100 quadrillion Btu of energy, or in plainer terms, over $1 trillion in energy expenditures annually. This sector alone comprises nearly half of all the energy consumed in the United States. Additionally, about seventy-five percent of all electricity produced in the U.S. is consumed by building operations. This precedent has convinced me that finding an alternative is worth the investment. The purpose of my thesis project is to explore substitutes to mechanical heating, ventilation, and air conditioning (HVAC) building systems. My project revisits the concept of natural ventilation and explores and evaluates its feasibility as an energy-saving and comfortable alternative to mechanical ventilation systems. Additionally, my project focuses on how buildings can be designed to naturally condition the indoor environments of our buildings. More specifically, I would like to help architects discover how they can utilize natural ventilation effectively. Using the TRNSYS simulation environment, I methodically show how a designer would use TRNSYS to make informed decisions about natural ventilation in their designs. My research is meant to be a valuable tool for other designers who are unsure or uncomfortable with utilizing this natural process to condition their buildings. The final deliverable of my thesis project is a comprehensive strategy for designers to incorporate natural ventilation in the early stages of their building design. Thesis: S.B., Massachusetts Institute of Technology, Department of Architecture, 2014.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 66-69).

Material quantities in building structures and their environmental impact

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Material quantities in building structures and their environmental impact De Wolf, Catherine (Catherine Elvire Lieve) Improved operational energy efficiency has increased the percentage of embodied energy in the total life cycle of building structures. Despite a growing interest in this field, practitioners lack a comprehensive survey of material quantities and embodied carbon in building structures. This thesis answers the key question: "What is the embodied carbon of different structures?" Three primary techniques are used: (1) a review of existing tools and literature; (2) a collaboration with a worldwide network of design firms through conversations with experts and (3) the creation of a growing interactive database containing the material efficiency and embodied carbon of thousands of buildings. The first contribution of this thesis is to define challenges and opportunities in estimating greenhouse gas emissions of structures, expressed in carbon dioxide equivalent (CO₂e). Two key variables are analyzed: material quantities (kgmaterial/m² or kgm/m²) and Embodied Carbon Coefficients (ECC, expressed in kgCO2e/kgm). The main challenges consist of creating incentives for sharing data, identifying accurate ECCs and resolving transparency while protecting intellectual ownership. The main opportunities include using Building Information Models to generate data, proposing regional ECCs and outlining a unified carbon assessment method. The second contribution is the development of an interactive online tool, called deQo (database of embodied Quantity outputs), to provide reliable data about the Global Warming Potential of buildings (GWP, measured in kgCO2e/m² and obtained by multiplying the two key variables). Given the need for a long-term initiative, a framework is offered to create an interactive, growing online database allowing architects, engineers and researchers to input and compare their projects. The third contribution is the survey of 200 existing buildings obtained through deQo. Two general conclusions result from this survey of building structures: material quantities typically range from 500 to 1500 kg/m² and the GWP typically ranges between 200 and 700 kgCO2e/m2. Conclusions from this survey include that healthcare buildings use more materials whereas office buildings have a lower impact. Additionally, specific case studies on stadia, bridges and skyscrapers demonstrate that the design approach can have a significant impact on the embodied carbon of building structures. Ultimately, this thesis enables benchmarking of the environmental impact of building structure Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2014.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 75-84).

The use of visual comfort metrics in the design of daylit spaces

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The use of visual comfort metrics in the design of daylit spaces Jakubiec, John Alstan It is desirable to design buildings with natural daylight and views to the outside, which can maximize passive solar heating, minimize electric lighting use and contribute to feelings of wellbeing and awareness. Unfortunately, the presence of daylight is not always a positive one. Excessive brightness, strong contrast or intense reflections from daylight can cause visual discomfort or the inability to perform tasks. Typically, the total amount of luminous flux incident upon a surface per unit area - illuminance - present is used to predict visual discomfort due to questions about the benefit and validity of luminance-based analysis measures that are more related to the way the human visual system perceives light. This thesis aims to advance the understanding and usefulness of visual comfort prediction to the point that it can become commonly used in architectural design processes. One method through which this is achieved is by testing the ability of visual comfort analysis to resolve subjective occupant comfort. It was found that of existing discomfort glare metrics, daylight glare probability (DGP) was the most likely to perform well in a variety of daylight conditions and space types. Furthermore, a long-term simulation and survey study found that between 53.7% and 70.1% of an occupant's visual satisfaction could be resolved by analyzing DGP, the presence of direct sunlight and predicted monitor contrast ratio. This choice of metrics was reinforced by a separate laboratory study, which found that 74.4% of subjective comfort could be resolved and identified new subjective luminance thresholds that identify likely discomfort. A new adaptive visual comfort model, the 'adaptive zone,' is proposed in this thesis to deal with spatiality and view in visual discomfort analysis. Finally, ways of applying these verified and new measures in design processes are tackled in this work by producing new temporal maps, spatial discomfort analysis, and plan-based mappings of visual satisfaction. Thesis: Ph. D. in Architecture: Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2014.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 137-144).

Computational exploration of the structural design space

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Computational exploration of the structural design space Mueller, Caitlin T This dissertation focuses on computational strategies for incorporating structural considerations into the earliest stages of the architectural design process. Because structural behavior is most affected by geometric form, the greatest potential for structural efficiency and a harmony of design goals occurs when global formal design decisions are made, in conceptual design. However, most existing computational tools and approaches lack the features necessary to take advantage of this potential: architectural modeling tools address geometry in absence of performance, and structural analysis tools require an already determined geometrical form. There is a need for new computational approaches that allow designers to explore the structural design space, which links geometric variation and performance, in a free and interactive manner. The dissertation addresses this need by proposing three new design space strategies. The first strategy, an interactive evolutionary framework, balances creative navigation of the design space with a focus on performance. The original contributions of this strategy center on enhanced opportunities for designer interaction and control. The second strategy introduces structural grammars, which allow for the formulation of broad and diverse design spaces that span across typologies. This strategy extends existing work in geometry-based shape grammars by incorporating structural behavior in novel ways. Finally, the third strategy is a surrogate modeling approach that approximates the design space to enable fast and responsive design environments. This strategy contributes new ways for non-experts to use this machine-learning-based methodology in conceptual design. These three complementary strategies can be applied independently or in combination, and the dissertation includes a discussion about possibilities and techniques for integrating them. Finally, the dissertation concludes by reflecting on its potential impact on design in practice, and by outlining important areas for future work. Key words: conceptual structural design, design space exploration, structural optimization, interactive evolutionary algorithm, structural grammar, surrogate modeling, structural design tools Thesis: Ph. D. in Architecture: Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2014.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 199-206).

Rafael Guastavino and the Boston Public Library

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Rafael Guastavino and the Boston Public Library Mroszczyk, Lisa J. (Lisa Jean) This thesis looks at the role of Spanish architect Rafael Guastavino in the design and construction of the Boston Public Library through an examination of correspondence, construction documents and meeting minutes from the Archives of the Trustees of the Boston Public Library, the Guastavino/Collins Archive at Columbia and articles in Boston newspapers. This examination explains how and why Guastavino received the contract for tile vaulting at the library, the method of construction, his relationship with architect Charles F. McKim and the effect the library had on Guastavino's reputation and career as a builder. Thesis: S.B., Massachusetts Institute of Technology, Department of Architecture, 2004.; Cataloged from PDF version of thesis.; Includes bibliographical references (pages 66-68).

Building community while building responsibly : a sustainable housing complex for Central Los Angeles

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Building community while building responsibly : a sustainable housing complex for Central Los Angeles Gutiérrez, Octavio, S.B. Massachusetts Institute of Technology Thesis: S.B. in Art and Design, Massachusetts Institute of Technology, Department of Architecture, 2001.; Cataloged from PDF version of thesis.

Thermal properties of granular silica aerogel for high-performance insulation systems

2022-01-13T07:53:53Z

Thermal properties of granular silica aerogel for high-performance insulation systems Neugebauer, Adam (Adam Halbert) Based on mounting evidence in support of anthropogenic global climate change, there is an urgency for developments in high-performance building techniques and technologies. New construction projects provide substantial opportunities for energy efficiency measures, but they represent only a small portion of the building stock. Conversely, while existing buildings are plentiful, they typically have a much narrower range of feasible energy efficiency options. Therefore, there will continue to be a need for the development of new and improved energy efficiency measures for new building construction and even more so for deep retrofits of existing buildings. This thesis provides an overview of the research performed into the on-going development at MIT of a high-performance panelized insulation system based on silica aerogel. Two test methods were used for measuring the thermal conductivity of the granules: the transient hot-wire technique and the guarded hot-plate system. Utilizing the hot-wire set-up, it was demonstrated that compressing a bed of granules will decrease the thermal conductivity of the system until a minimum point is reached around the monolithic density of the aerogel. For the Cabot granules, this was seen at 13 mW/m-K and about 150 kg/m3. The MIT granules showed equal performance to the Cabot granules at bed densities 20-30 kg/m3 lower. The hot-plate testing was able to experimentally evaluate previous analytical predictions regarding the conductivity impact of the internal panel truss and the under-prediction of radiant heat transfer in the hot-wire method. Hot-wire testing was also done in a vacuum chamber to quantify potential performance improvements at reduced air pressures. Since a vacuum would require the incorporation of a barrier film into the panel system, some analyses were done into the thermal bridging potential and gas diffusion requirements of such a film. Additionally, physical prototyping was done to explore how the film would be incorporated into the existing panel design. The aerogel-based insulation panel being developed at MIT continues to show promise, though there are still plenty of opportunities remaining in the development cycle. Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, 2013.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (pages 65-67).

Comparison of simplified models of urban climate for improved prediction of building energy use in cities

2022-01-13T07:53:53Z

Comparison of simplified models of urban climate for improved prediction of building energy use in cities Street, Michael A. (Michael Anthony) Thermal simulation of buildings is a requisite tool in the design of low-energy buildings, yet, definition of weather boundary conditions during simulation of urban buildings suffers from a lack of data that accounts for the UHI effect. To overcome barriers preventing the use of more representative climate data in building thermal simulations, this thesis evaluates two recently developed methods for generating urban weather files from a rural station. The two methods examined are computationally inexpensive. The first method is the urban weather generator (UWG) a model developed by Bueno et al. and the second is a temperature alteration algorithm developed by Crawley 2008. Actual weather data is used to validate the modeled urban data. Actual and modeled weather data is then used in simulation of a typical single-family and small office building to quantify normalized energy use metrics of urban buildings. Applying the UWG to appropriate rural weather data reduces the error associated with energy prediction of an urban single-family building by nearly half (21% to 13%). If the Crawley algorithm is applied to rural data, the resulting weather data will produce simulation results that are lower (- 8%) and upper limits (+ 11%) to the actual urban energy simulation results. For applications that either require feedback with the urban design or have extensive data on the urban morphology we recommend the use of the UWG with a radius of 500 m. For applications that lack urban site data and are order of magnitude estimations, the Crawley algorithm generally is able to provide extremes of the predicted EUI. Thesis (S.M. in Building Technology)--Massachusetts Institute of Technology, Dept. of Architecture, 2013.; Cataloged from PDF version of thesis.; Includes bibliographical references (p. 127-131).

Lightweight concrete : investigations into the production of natural fiber reinforcement

2022-01-13T07:53:53Z

Lightweight concrete : investigations into the production of natural fiber reinforcement Garbis, Leonidia Maria The purpose of this study is to investigate the benefits of adding natural fiber tensile reinforcement to aerated concrete. Concrete is a great composite material which can be created in various proportions and with various materials to alter its strength, density and porosity, amongst other properties. Concrete which is used commonly in construction of columns, beams, and slabs acts well in compression but fails under tension. The common solution is to reinforce the structure in areas where it experiences tension with steel. There are other materials besides steel which also take tension well. Natural fibers for example come in various strengths and types and would create lighter and perhaps more sustainable beam designs. Natural fibers have been used for their availability, workability, and high tensile strengths for centuries. This research discovers how the natural fibers distribute within the mixture and how they affect the aeration of the concrete, as well as how they affect the strength. Multiple samples are cured with different fiber types and in different proportions within the mixture. Furthermore, similar experimentation is conducted to discover an ideal ratio of aggregate to aerated concrete mix. The aggregate gives the concrete greater strength and economy, but could negatively affect the aeration. The various concrete mixes are poured and allowed to cure to maximum strength before indirect tensile tests and compression tests are conducted. The effects of creating smooth aerated concrete molds are also investigated. All experiments conducted are precursory to an ultimate tensile reinforced aerated concrete beam design with an aggregate mix and smooth surfaces. Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Architecture, 2013.; Cataloged from PDF version of thesis.; Includes bibliographical references (p. 34).

Quantifying architects' and engineers' use of structural design software

2022-01-13T07:53:59Z

Quantifying architects' and engineers' use of structural design software Arnaud, Virginie B. (Virginie Blandine) Both architects and engineers encounter significant barriers and hurdles that compartmentalize both fields and increase the complexity of collaborative design. In addition to little interaction between both fields, software programs are limited in many aspects. That is why the current industry's organization and tools confront engineers and architects with significant challenges. If improvements are made, they would reduce designers' effort and the time spent to overcome these challenges, and would positively impact the quality of their work. Thus, it is necessary to identify problems in current tools and to study the design process to find areas for improvement in design software programs. This paper presents a discussion on the limitations of structural design software and a study on the differences between architects and engineers during the design process through the analysis of the use of a newly developed framework: StructureFIT. This tool was recently developed at MIT and aims to create an interface between both disciplines. In this thesis, a usability study and a questionnaire were specifically designed to gather data from 38 graduate students of architecture and engineering. This material aims to assess users' level of satisfaction with current tools, identify the areas to be improved in current software programs, quantify the differences in designers' practices, and assess StructureFIT. The analysis of findings suggests that users are not fully satisfied with current tools. The reason is that most design tools do not easily foster the exploration of structural alternatives due to lack of user-friendliness, compared to StructureFIT that did meet the users' demands. This work also provides a better understanding of engineers' and architects' respective design approaches as discussed through the analysis of the usability study results. Lastly, StructureFIT does provide a positive design exploration for designers, since the tool enabled users to dramatically improve structural performance while providing a wide diversity of solutions. The richness of generated efficient design solutions is what makes StructureFIT an innovative and promising approach. Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2013.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis. Page 137 blank.; Includes bibliographical references (p. 135-136).

Energy reduction strategies for existing Air Force healthcare facilities

2024-03-18T19:43:21Z

Energy reduction strategies for existing Air Force healthcare facilities Ramos, Jose I. (Jose Israel) Federal buildings are required to reduce 30% of their energy use intensities (energy use per square foot) by 2015 and 37.5% by 2020. Additionally, 15% of federal buildings are required to achieve an Energy Star Rating of 75 or above by 2015. Despite rigorous efforts, current Air Force healthcare building performance reveals only a 15% decrease has been achieved from the 2009 baseline levels and only 12% of the building inventory holds the Energy Star Rating. Projections similarly reveal full compliance by 2020 may not be achievable, therefore, the need for a comprehensive and more robust effort is proposed. This thesis seeks to develop a road map for the Air Force's 68 existing healthcare buildings towards compliance by 2015. A methodology has been developed that leverages the Air Force's state-of-the-art energy efficiency strategy, the building energy performance analysis for 68 healthcare facilities including ten in-depth case studies, and multi-agency interviews to produce the road map. Strategic energy management plans, building system retrofits, whole building retro commissioning, occupant behavior and medical equipment plug loads and standby loads have been assessed. Investment costs, energy savings, and return on investments present timeline objectives intended to deliver a comprehensive strategy towards energy savings in Air Force healthcare facilities by 2015. Findings indicate that an energy master plan that incorporates a systematic building diagnostics approach targeting HVAC equipment and system operations as the most effective strategy. The results reveal that HVAC retrofits and implementation of no cost measures such as temperature setpoints and setbacks collectively reduce building energy use by 85% and energy use intensities by 50% by 2015. Projections include a total budget request of $43.5 million, annual cost savings of $4.1 with a 9.4% return on investment. Thesis (S.M. in Architecture Studies)--Massachusetts Institute of Technology, Dept. of Architecture, 2013.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (p. 118-124).

Analysis and characterization of ancillary service demand response strategies for variable air volume HVAC systems

2022-01-13T07:53:53Z

Analysis and characterization of ancillary service demand response strategies for variable air volume HVAC systems Blum, David H. (David Henry) Output variability and prediction difficulties with respect to solar and wind electricity resources increase the requirement of grid-scale reserve capacity and add strain to existing firm generators used for reserves and other ancillary services. Residential and commercial buildings account for a large portion of the electricity consumed in the U.S. and can play a significant role in smart grids to help meet challenges brought about by intermittent renewable generation. High resolution power consumption and HVAC performance data measured in a real building was used to identify real-world operational qualities of VAV systems to be considered by building researchers and building practitioners. This includes the relative magnitude of building power loads, the direct and indirect relationships between environmental conditions and HVAC power consumption, the discrete operation of staged or cycled power loads, and the presence of HVAC operational faults. Also, three static pressure adjustment tests were performed over a one day period. Results showed that fan and terminal unit controllers responded within two minutes and system air flowrate was strongly related to power consumption. Dynamic models were created in order to simulate the performance of a VAV system providing spinning reserves by four different common demand response strategies: zone air dry bulb temperature setpoint adjustment (ZDBA), duct static pressure setpoint adjustment (SPA), supply air temperature adjustment (STA), and chilled water temperature adjustment (CWA). Simulations were run over ranges of implementation and cooling load intensities and the results were used to create characteristic curves for each strategy, which map performance in terms of system power consumption reduction, system airflow reduction, and zone temperature rise. Inflection points on the curves that delineate performance effectiveness are found to result from maximum or minimum terminal unit damper positions. In the future, the development of mathematical functional forms of these characterization curves could help predict and optimize the performance of VAV systems in providing ancillary services to electricity networks. Thesis (S.M. in Building Technology)--Massachusetts Institute of Technology, Dept. of Architecture, 2013.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (p. 113-119).

Model predictive control for energy efficient cooling and dehumidification

2022-01-13T07:53:53Z

Model predictive control for energy efficient cooling and dehumidification Zakula, Tea Energy has become a primary concern in countries worldwide, and is a focus of debates on national security, climate change, global economy, and the developing world. With more people in developing countries adopting the lifestyle of western countries as rapidly as possible, limited only by economic means, a tremendous increase in world's energy consumption in the next few decades seems difficult to avoid. The building sector is of particular interest, since it accounts for a large portion of the total energy market: currently in the U.S. forty percent of the total energy and seventy percent of electricity is consumed by residential and commercial buildings. Within commercial buildings, cooling equipment represents the second largest consumer of electricity. This research analyzes one option for reducing space cooling energy consumption, an advanced cooling system termed low-lift cooling system (LLCS). The system comprises thermally activated building surfaces (TABS) with water running through pipes embedded in a building's construction to serve both as cool storage and as a means of delivering the cooling effect. The LLCS utilizes model predictive control (MPC) algorithm that, based on weather and load predictions, determines the cooling strategy over next 24 hours that minimizes energy consumption. Different objectives, such as minimizing the total cost of electricity, can be achieved by modifying the objective function. Currently there is no commercially or publicly available software that allows the analysis of systems that employ MPC. The first goal of this research was to develop a computer algorithm that can simulate the LLCS performance, but also the performance of other cooling systems that employ MPC. The second goal was to analyze the LLCS performance across different U.S. climates relative to a conventional cooling system and to explore different dehumidification strategies that can be used in combination with the LLCS. This research significantly advances the knowledge of simulation and performance of the LLCS. The developed MPC algorithm enables a systematic study of primary factors influencing dynamic controls and the savings potential for an individual building. The algorithm is highly modular, enabling easy future expansion, and is sufficiently fast and robust for an implementation real buildings. The results of the analysis suggest that the electricity savings using the LLCS are up to 50% relative to an all-air system under conventional control and up to 23% relative to an all-air system under MPC. The savings were achieved through lower fan and pump transport energy and better utilization of part-load efficiencies inherent in inverter-compressor equipment, a result of the TABS technology and the optimal control. Thesis (Ph. D. in Building Technology)--Massachusetts Institute of Technology, Dept. of Architecture, 2013.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (p. 147-154).

Evaluating the performance of natural ventilation in buildings through simulation and on-site monitoring

2022-01-13T07:53:53Z

Evaluating the performance of natural ventilation in buildings through simulation and on-site monitoring Cheng, Haofan Natural ventilation in buildings is capable of reducing energy consumption while maintaining a comfortable indoor at the same time. It is important that natural ventilation is taken into consideration in the early design stage, probably through simulation program. However, existing simulation programs are limited because of their model assumption, simulation efficiency and user friendliness. In this document a simulation program, CoolVent, is presented. It implements a multi-node, thermal and energy coupled model to simulate natural ventilation in buildings. The program is validated to be effective and efficient in simulation. Combined with the DOE building database, CoolVent evaluates the performance of different ventilation modes in different types of building and weather conditions. The second half of this thesis includes a detailed on-site monitoring study of a naturally ventilated building in Boston. It details the post-occupancy system characteristics. The monitoring results have also been compared with CoolVent. The simulation results are verified by comparing with the monitored ones. The program is then used to evaluate the potential of improved operation. Thesis (S.M. in Building Technology)--Massachusetts Institute of Technology, Dept. of Architecture, 2013.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Vita. Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (p. 120-121).

Recharging the facade : designing and constructing novel BIPV assemblies

2022-01-13T07:53:53Z

Recharging the facade : designing and constructing novel BIPV assemblies Keller, Alexander Freimark Building Integrated Photovoltaics (BIPV) have been the subject of research and design applications for several decades. While some large-scale applications have been realized, prohibitively high costs and multiple technical complexities persist. A main cause of these challenges is a lack of system-level design and engineering ofphotovoltaic (PV) systems coupled with traditional methods of building construction. PV installation remains a highly specialized construction practice and is typically completed by skilled experts in the field who deal with intricate electrical connections like wiring to batteries and inverters. This complicated installation process, in addition to other soft costs like permitting and system components, account for approximately fifty percent of the overall cost of a solar power system. The installation of photovoltaic systems must be simplified and streamlined to make PV more cost effective. Furthermore, existing BIPV strategies fail to address two key concerns that have negatively impacted the power output and efficiency of the system: optimal tilt angle and high cell temperature. Low cell efficiency will continue to hinder BIPV's penetration in the market without design strategies that ensure higher yields. This thesis presents the design, development, and construction of two novel BIPV products. One is integrated with masonry construction, and the other is integrated with pre-fabricated panel construction. An experimental methodology was developed in order to test and analyze the effectiveness of the systems' design strategies for providing an optimal tilt angle, cooling and heat recovery capabilities, and finally, financial viability. Preliminary results reveal that the optimal geometry of the system provides 30% more power compared to vertically oriented wall systems. Secondly, the strategy for cell cooling provides the system with on average 9% more power. Lastly, the integration of these systems during construction can decrease overall costs by as much as 17% compared to typical PV systems. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2013.; Pages 156-157 blank. Cataloged from PDF version of thesis.; Includes bibliographical references (p. 149-154).

The design and implementation of a smartphone illuminance meter

2022-01-13T07:53:53Z

The design and implementation of a smartphone illuminance meter Sparks, Devon D The proliferation of consumer smartphones has offered new opportunities for environmental sensing and mobile computation. Recent smartphone models - equipped with GPS trackers, accelerometers, megapixel cameras and rich software stacks - offer the possibility of emulating specialized tools completely in software. This paper documents recent efforts to build a robust, smartphone-based illuminance meter application, and describes its prototype implementation. Though hardware and software constraints prevent the complete development of such a prototype, its use and potential are demonstrated. Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Architecture, 2013.; Cataloged from PDF version of thesis.; Includes bibliographical references (p. 14-15).

Deleveraging domesticity : incremental design forays on middle income housing

2022-01-13T07:53:53Z

Deleveraging domesticity : incremental design forays on middle income housing Miller, Christopher M., M. Arch. (Christopher Michael). Massachusetts Institute of Technology Housing today has little do with architecture. Design is a currency of services, while housing today is intensively packaged as a consumer good. It is packaged with land as speculative real-estate, and bundled abstractly into mortgage-backed securities for trade in global investment markets. Both strategies allow people of ordinary means to assume it's monumental cost. Because so very few can buy housing outright, it is built by debt and for debt. This thesis proposes an alternative, in which the critical role of mortgage-financing is directly supplanted by a new set of incremental residential design services. It proposes that middle and low income housing can be not only paid for, but also designed and built during occupancy. Proposed as the centerpiece of a new mode of professional architectural practice, this flexible timeline facilitates reconsideration of housing's materials, labor logistics, and constructional methodologies. The same timeline can accommodate its individual owners' changing needs throughout a progressively tailored and domestically integrated process. Though rental markets may fluctuate, credit scores plummet, mortgage qualifications creep, and income-inequality may intensify, incremental design services can pin the production of housing to that irrespectively distributed and far more egalitarian commodity of time. Given more or less time, these can serve both middle and low income households at equal and unsubsidized standards. The structure of this thesis first elaborates and quantifies the underlying need and argument for designed incremental housing in the United States. It then explores the enabling strategies, attitudes, and issues that arise surrounding three distinct design exercises. These each comprise an approximately eighty thousand dollar magnitude of cash expense, but diverge in value by articulating design logistics as a parallel currency. They are respectively urban, suburban, and rural in setting. They are tailored to a plausibly fictitious clientele of respectively high, middle, and low incomes, and so adopting HUD's definition of affordable housing costs as 30% or less of household income, are conducted in the course of three, six, and twelve years respectively. Their single and central commonality is a complete prohibition of paper debt. Thesis (M. Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 2013.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis. Pages 172 and 173 blank.; Includes bibliographical references (p. 166-171).

Lightweight concrete : investigations into the production of variable density cellular materials

2022-01-13T07:53:53Z

Lightweight concrete : investigations into the production of variable density cellular materials Cooke, Timothy Graham This research focuses on the intersection between material composition and form in the development of a new type of concrete. As concrete is the most widely used building material in the world, innovation in this material has more potential to effect change in our built environment than innovation in any other. With the objective of minimizing raw material consumption and energy use, this work attempts to develop methods for creating a cellular lightweight concrete with variable density that can be cured at room temperature. Most aerated concretes traditionally require high temperature and high pressure curing; the goal of this research is to create a lower embodied energy product through the use of room temperature curing, while at the same time maximizing performance through variation of the density of the material through its section-essentially locating stronger material where it is needed. This more durable and versatile concrete product will be able to compete with traditional lightweight concretes, which provide benefits such as insulation, as well as normal-weight concrete, which is harder and stronger. The research aims to capitalize on the inherent heterogeneity of the material by producing a substance whose internal properties can be varied based on the needs of a specific part of a building. I am interested in replacing the concept of the "assembly" of materials to gain a desired function with a more unitary concept: the manipulation of a single material to meet a building's multiple needs. A desired outcome of the work is to reconceive how we put buildings together, not as assemblies of discrete elements but as monolithic yet malleable wholes. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2012.; Cataloged from PDF version of thesis.; Includes bibliographical references (p. 123-127).

Toward zero net energy buildings : optimized for energy use and cost

2022-01-13T07:54:12Z

Toward zero net energy buildings : optimized for energy use and cost Brown, Carrie Ann, Ph. D. Massachusetts Institute of Technology Recently, there has been a push toward zero net energy buildings (ZNEBs). While there are many options to reduce the energy used in buildings, it is often difficult to determine which are the most appropriate technologies to implement. To reach zero energy, some designs extensively rely on the use of photovoltaics (PV) to meet the building load, without first exploring the benefits of deep energy efficiency measures. To minimize energy use in a cost effective manner, a tool has been developed to help compare distributed generation (DG) alternatives with energy efficiency measures early in the design process. It was designed to be accessible to non-technical users and to allow them to set up and run simulations in just a few minutes. The tool was built on top of Design Advisor, which provides the capability to analyze a suite of energy efficiency measures such as insulation, window type, schedules, and HVAC types, as well as green and cool roofs. New modules that have been developed for Design Advisor include: heat pumps, absorption chillers, PV, cogeneration, and cost. Using capital cost above baseline as the independent variable, the tool outputs the net annual energy use and total cost (capital and energy) for each case analyzed in the optimization. This allows the user to understand the range of technologies and costs involved along the path from the basecase to a ZNEB. Thesis (Ph. D. in Building Technology)--Massachusetts Institute of Technology, Dept. of Architecture, 2012.; Cataloged from PDF version of thesis.; Includes bibliographical references (p. 119-125).

Study and prediction of the energy interactions between buildings and the urban climate

2022-01-13T07:54:12Z

Study and prediction of the energy interactions between buildings and the urban climate Bueno Unzeta, Bruno Urbanization produces higher air temperatures in cities than in the undeveloped rural surroundings. This phenomenon is known as the Urban Heat Island (UHI) effect and has been measured in different cities around the world. Conventional building energy programs use standard meteorological databases obtained from measurements at operational weather stations, which are usually located in open areas outside of the city, typically at the airport. Therefore, air temperature measurements may not include the UHI effect. The UHI effect can have an impact on the energy consumption of buildings, especially residential and naturally ventilated buildings. At the same time, the energy performance of buildings can affect outdoor air temperatures, mainly through the waste heat emissions from outdoor air-conditioning equipment. Consequently, there are situations in which the interactions between the indoor and outdoor environments are reciprocal and thus both domains have to be solved simultaneously. This thesis presents a study of the energy interactions between buildings and the urban climate through the development and evaluation of a set of models. Based on first principles, these models include three different Urban Canopy and Building Energy Models (UC-BEMs), with different levels of detail and applications, and a novel urban climate prediction tool, the Urban Weather Generator (UWG). Developed at the intersection of building energy and urban climate studies, the research builds on fundamental knowledge in both domains. The UC-BEMs account for building thermal effects on climatological predictions and have the potential to predict building energy consumption at urban scale. The UC-BEMs can be coupled with mesoscale atmospheric simulations, establishing a multi-scale model approach from the atmosphere down to buildings that can be used to analyze the impact of future climate change scenarios on the urban climate and the energy consumption of buildings. The UWG calculates site-specific urban climate conditions from measurements at an operational weather station. The model can be used alone or integrated into existing programs in order to account for the UHI effect in building energy simulations. The UWG is evaluated with field data from Toulouse, France, and Basel, Switzerland. Thesis (Ph. D. in Building Technology)--Massachusetts Institute of Technology, Dept. of Architecture, 2012.; Cataloged from PDF version of thesis.; Includes bibliographical references (p. 125-130).

The effect of geometry and topology on the mechanics of grid shells

2022-01-13T07:54:23Z

The effect of geometry and topology on the mechanics of grid shells Malek, Samar R. (Samar Rula) The use of grid shell structures in architecture and structural engineering has risen in the past decade, yet fundamental research on the mechanics of such structures is lacking. Grid shells are long span structures comprised of a lattice of single layer members forming a curved surface. Grid shells can be made of a wide range of materials from steel to wood. They have potential to be used in readapting existing spaces or in new aesthetically pleasing structures. By studying their mechanics, engineers can be more effective at the schematic phase of design so that the potential of grid shells can be maximized. This research conducts a parametric study that varies the topology and topography of grid shells. The parametric space is framed around real-world design constraints including the grid spacing, panel shape, span-to-height ratio and the use of double curvature. In this thesis, the buckling capacity is evaluated using finite element analysis for two typical grid shell geometries: the spherical cap and the corrugated vault. First, a spherical cap is considered for which an analytical solution exists and therefore the accuracy of the numerical procedure is validated. Simple closed-form solutions are derived using the concept of the equivalent continuum and compared to the numerical models. Then, the parametric study of the spherical cap is performed including variations of the grid spacing, the span to height ratio and the panel shape (triangles and quadrilaterals). Having determined the efficiency of the computational tool the study is extended to the barrel vault. Here the new features of the analysis are the use of double curvature by introducing corrugation along the edge and the crown. By understanding the fundamental mechanical behavior of grid shells, design guidelines aimed to maximize their capacity and efficiency and intended to facilitate the discussion between architect and engineer are proposed. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2012.; Cataloged from PDF version of thesis.; Includes bibliographical references (p. 128-131).

Cleanroom design

2022-01-13T07:54:12Z

Cleanroom design Erickson, Douglas H The development of the integrated circuit which replaced the vacuum tube, started the size reduction process for computer components. These integrated circuits are made from silicon (chips) and are comprised of electronic switches, or gates. The gates are measured in size of microns. The diameter of a human hair is approximately 60 microns across. Facilities that develop, and manufacture these integrated circuits require the strictest guidelines for environmental controls and prevention of potential health hazards that personnel may encounter while working in these facilities. The major environmental controls are particle size and number, temperature, relative humidity, air flow velocity, and pressure. Providing this and other forms of control are used to develop what are called cleanrooms. Cleanrooms are used for the manufacture of a number of different kinds of products. The focus of this research will be on the microelectronics industry. This industry leads all other industries in developing systems, standards, and monitoring technologies, to control microcontamination which is the essence of what a cleanroom does. This thesis will be divided into two parts. The first part defines what a cleanroom is and what it is comprised of. Next, there will be methods presented to design this type of space in a more energy and cost efficient manner. The second part involves the research in the vertical laminar flow aspect of operating a cleanroom. The vertical laminar flow offers a structured method for controlling air flow and provides an effective means for discharging particulates out of the cleanroom. By comparison, the conventional air flow system throws the particulates in a random fashion. The vertical laminar flow has its limitations. By itself, the vertical flow operates well, but people, and equipment cause turbulence which disrupts its effectiveness. Working with these variables through research, an alternate method of working with this vertical laminar flow was developed. The results, recorded by photographs show an alternative for dealing with the turbulence and eddys caused by the operations in the cleanroom. There will be a discussion followed by a number of questions, and responses which will be the basis for this research on vertical laminar flow. Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1987.; Includes bibliographical references (leaves 147-150).

Mapping comfort : an analysis method for understanding diversity in the thermal environment

2022-01-13T07:54:12Z

Mapping comfort : an analysis method for understanding diversity in the thermal environment Webb, Amanda Laurel Our thermal experience is never neutral. Whether standing near a cold window in the winter, or in the shade on a sunny day, we constantly experience a rich set of thermal stimuli. Yet, many of the tools used in professional practice to analyze and design thermal environments in buildings do not account for the richness of our thermal experience. This disconnect between our analysis tools and our experience results in buildings that use more energy than they should, and that leave occupants dissatisfied with their thermal environment. This thesis seeks to bridge the gap between our thermal experience and our building thermal analysis tools. A unique methodology has been developed that produces mapping of thermal comfort parameters in all three spatial dimensions, as well as over time. Both heat balance and adaptive comfort indices have been incorporated into the methodology. An accompanying software program, called cMap, has been developed to illustrate the ways that this methodology can be used with existing energy analysis software and to demonstrate how it can fit into existing analysis workflows in professional practice. Thesis (S.M. in Architecture Studies)--Massachusetts Institute of Technology, Dept. of Architecture, 2012.; Cataloged from PDF version of thesis.; Includes bibliographical references (p. 67-70).

Localized design-manufacture for Developing Countries : a methodology for creating culturally sustainable architecture

2022-01-13T07:54:12Z

Localized design-manufacture for Developing Countries : a methodology for creating culturally sustainable architecture Peinovich, Ella Can improved technology uptake in developing countries promote cultural sustainability and enable the production of endogenous solutions for development? This thesis, which focuses on technology dissemination for the benefit of under-served communities, is aimed at building capacity locally for self-sustained manufacturing processes using Computer-Aided Design and Computer-Aided Manufacturing (CAD/CAM) tools suited to create solutions for local infrastructures. Unlike imposed exogenous solutions, an approach is needed which promotes localization of the design-manufacture process to encourage cultural sustainability. The research is threefold: 1) catalogue cultural artifacts that can benefit from digital reproduction for widespread methodological adoption 2) build capacity locally through sustained educational channels and 3) implement technological manufacturing processes that are culturally sustainable and replicable. Thesis (M. Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 2012.; Cataloged from PDF version of thesis.; Includes bibliographical references.

Estimating material and energy intensities of urban areas

2022-01-13T07:54:12Z

Estimating material and energy intensities of urban areas Quinn, David James, Ph. D. Massachusetts Institute of Technology The objective of this thesis is to develop methods to estimate, analyze and visualize the resource intensity of urban areas. Understanding the resource consumption of the built environment is particularly relevant in cities that are rapidly growing, as the urban forms that emerge have long-term consequences for both the quality of life of the inhabitants, and their future material and energy demands. This work was completed by assembling datasets of cities from around the world, identifying geometric patterns in the built environment, relating these geometric patterns to material and energy intensities, and illustrating these intensities in a visually intuitive way. This thesis describes a standardized analytical approach to assess the physical characteristics of the built environment, enabling comparisons to be made between cities. This approach provides a preliminary assessment of resource intensities that may be useful for decision-makers to compare differences among a variety of urban forms. Finally, a new web-map visualization tool has been developed that enables users to gain an understanding of the resource intensity of 40 cities in the USA. This tool allows the user to explore the resource intensity of urban areas using a web-browser, and to dynamically generate reports that can compare areas within a city, or entire cities, to each other. Thesis (Ph. D. in Architecture: Building Technology)--Massachusetts Institute of Technology, Dept. of Architecture, 2012.; Cataloged from PDF version of thesis.; Includes bibliographical references (p. [189]-199).

Disaster debris management and recovery of housing stock in San Francisco, CA

2022-01-13T07:54:12Z

Disaster debris management and recovery of housing stock in San Francisco, CA Saiyed, Zahraa Nazim This thesis investigates the potential effects of a 7.2 magnitude earthquake in San Francisco City, particularly the implications on San Francisco's residential housing stock and impacts on the construction and demolition waste stream. The study uses System Dynamics methodology to analyze the feasibility of recycling disaster debris as new construction material to rebuild the diminished housing stock. A meta-analysis identifies capacity requirements for transport and processing material, and seeks to project a time frame for refurbishing lost housing. Simulated scenarios of policy measures provide the basis for recommendations on improving San Francisco's post-disaster recovery as related to debris handling and reoccupation of housing. Results show that an increased use of recycled content products diverts upwards of 1.6 million tons of debris from landfill, with an additional two years of delay in overall recovery. Under this hypothesis, and considering residential housing recovery as a proxy for city-wide recovery, the effects of a largescale earthquake would require an estimated recovery time of 6.8 years. Future work will address additional influencing variables of economics while honing existing factors within the dynamic model, as well as applications to other vulnerable cities in a domestic and international context. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2012.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student submitted PDF version of thesis.; Includes bibliographical references (p. 156-160).

Collapse mechanisms of small-scale unreinforced masonry vaults

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Collapse mechanisms of small-scale unreinforced masonry vaults Shapiro, Elaine Elizabeth The structural behavior of masonry arches under various forms of loading is well-studied; however, the three-dimensional behavior of barrel vaults and groin vaults is not as well understood. This thesis aims to address this problem by performing scale model testing of barrel and groin vaults as a complement to analytical solutions. The behavior of the model vaults are observed in four cases: (1) spreading supports, (2) vertical point loads applied at various locations of the vault's geometry, (3) point loads applied to an initially deformed vault, and (4) horizontal acceleration through tilting. In all cases, extensive experimental testing is carried out on a subset of three model vaults: two barrels and one groin vault, all with the same radius and thickness ratio but with different angles of embrace. High-speed cameras are used to capture the collapse mechanism of the vaults. The analyses include equilibrium methods executed through Excel and Matlab programs, publicly available online applets for arch stability, and hand calculations. The testing and analysis carried out in this thesis reveal several properties that can be used by engineers studying existing structures. First, a groin vault's spreading capacity is determined by the constituent barrel vault that is spreading. This simplifies the analysis to a two-dimensional problem. Second, the load capacity of a barrel vault is linearly proportional to the initial deformation in span. So, if a vault experiences a span increase that is 25% of the maximum it can withstand, its load capacity decreases by 25%. Nearly all vaults have experienced deformations due to settlement over time and will therefore respond differently to loading than a perfect vault which is the common starting point in analysis. This work can be applied to the understanding and maintenance of masonry vaults in service throughout the world. Thesis (S.M. in Building Technology)--Massachusetts Institute of Technology, Dept. of Architecture, 2012.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student submitted PDF version of thesis.; Includes bibliographical references (p. 61-63).

Sonic facade, creating a sounding architecture

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Sonic facade, creating a sounding architecture Granville, Alina (Alina T.) While architecture inherently makes sound when people and the environment interact with it, architects seldom orchestrate a building to produce sound. This thesis proposes a sonic facade that turns an existing building into a sound producing instrument. Sonic facade is a wind powered sound producing device that can be integrated into a wall structure. The facade is produced out of a series tubes, or more technically, a series of air column vibrators. While all the tubes may be the same length, the combination of three different types of tubes produces different sounds. This thesis proposes a seven rule shape grammar for users to determine the placement and implementation of the sonic facade on an existing building and site. The shape grammar allows for a range of simple to complex possibilities that could be applied to a variety of buildings. The sonic facade not only has an aural quality, but it is also an indicator and transmitter of the outside world. When the tubes pass from the outside to the inside of a building, the wind, the rain, and passersby bring sound inside the building. Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Architecture, 2012.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (p. 94-95).

Energy flows : empowering New Orleans

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Energy flows : empowering New Orleans Guiraud, Florence Nathalie This thesis claims to develop alternative energy-harvesting systems by looking at their implementation at the residential scale in order to facilitate the economical autonomy of a community and thus improve its living conditions. It can be said that the evolution of the farming tools brought an opportunity of emancipation to farmers -- greater production yields than what was necessary to subsist were sold on markets thus increasing the economical power of the farmer and conceptually stretching the domestic space to the field owned. Taking the hurricane-devastated, slow-recovering New Orleans as a site for intervention, the thesis will challenge existing building materials for their flood resistance and reaction to an inundated environment while developing tools to harvest energy from the multiple environmental conditions present at this location. Ultimately, the thesis will try to demonstrate how these tools will influence geography and the concept of property. Six years after the devastation of hurricane Katrina, New Orleans is still struggling to gain economical growth solely depending on tourism and oil-related businesses. Louisiana's offshore oil industry benefits from an exemption of state taxation, creating an unbalanced economical and ecological situation. Louisiana's oil is being drilled without Louisiana receiving any monetary compensation, and the bayou's biodiversity is being devastated from reoccurring oil spills along with the dredging of the sediments at the bottom of the Mississippi river to facilitate the movement of tankers and protect settlements along the river's edge. New Orleans' population currently relies on the Army Corps of Engineers' infrastructure and a colonized oil industry to survive, while it could insure its own protection against natural disasters by regaining stewardship over land and water, and by competing with the oil industry through the creation of an alternate energy market. Through the investigation of newly developed materials and energy systems created for industrial uses, and by understanding their potential in the domestic realm, this thesis will seek to create new techniques of harvesting energy which will respond to the different climatic and topographical conditions present in New Orleans; the strong winds, the variations in tides, the current velocity of the Mississippi River and the potential of the bayou's biodiversity. Moreover, it hopes to generate new methods of residential constructions and typology, adapted to different disaster threat level conditions particular to the area, and potentially reorganize the domestic realm according to its new added functions. Recognizing the possibility of another flood in New Orleans and understanding the effect of the Army Corps of Engineer's flood prevention devices on the bayou's ecosystem, the thesis's methodology will require a thorough analysis of existing hydrological methods of flood protection and water based harvest, hydro-morphological and geomorphological patterns, creating a catalog of tools from which one may start speculating in the design phase. An analysis of selected urban and architectural precedents will be useful to assess the potential of each tool and its particular repercussions on the landscape and the organization of the greater urban form. Further analysis will be devoted to energy producing and harvesting devices, procuring the thesis with insights of their impact on existing infrastructure and their potential at the residential scale for both energy performance and architectural adaptation. The content of this research will be continuously tested. Other important implementation strategies, land organization and transformation will be investigated through different scales of physical models, constantly informing the specificity of the design to its physical and ecological environment. Thesis (M. Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 2012.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (p. 120-121).

Effects of planning and policy decisions on residential land use in Singapore

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Effects of planning and policy decisions on residential land use in Singapore Davis, Noel R A study of current land use in Singapore shows that through effective long-term space planning, the island city-state has maintained an adequate stock of developable residential land to meet its most ambitious maximum population projections. Two indicators of residential land use efficiency are defined: Residential Land Use Footprint, [Lambda]r, measures the per-capita residential land requirement; Mean Residential Redevelopment Time, [Tau]r, defines the weighted average time for the government to redevelop a typical plot of residential land. A dynamic stock-and- ow model is described to calculate the historical residential land use footprint and mean residential redevelopment time between 1990 and 2011. Finding that the primary driver of residential land use footprint is the change in household occupant density, a System Dynamics model is developed to simulate the historical housing price, supply response, and occupant density. Using a stock management structure to modulate housing supply and commodity dynamics structures to determine housing prices, the calibrated model is used to forecast the behavior trends of several housing policy and population growth scenarios. Thesis (S.M. in Building Technology)--Massachusetts Institute of Technology, Dept. of Architecture, 2012.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (p. 191-197).

Heat recovery and thermal storage : a study of the Massachusetts State Transportation Building

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Heat recovery and thermal storage : a study of the Massachusetts State Transportation Building Bjorklund, Abbe Ellen A study of the energy system at the Massachusetts State Transportation Building was conducted. This innovative energy system utilizes internal-source heat pumps and a water thermal storage system to provide building heating and cooling. The potential benefits of this type of system include both energy savings and operating and equipment cost savings when compared to more conventional building heating and cooling systems. The study involved monitoring of equipment performance, computer simulation of the building energy system dynamics, and analysis of actual and modelled system efficiency. It was found that the building is presently operating as a 'low energy' building, despite a number of factors which have limited the heat pump system's capability to entirely meet winter heating requirements. Significant additional operation efficiency and cost savings are potentially available if a variety of measures are undertaken, including: stratification of the thermal storage system, utilization of demand management controls, and increased lighting system efficiency. Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture; and, (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1986.; Typescript (photocopy).; Includes bibliographical references (v. 2, leaves 288-292)

Modernizing the passing joint : a standardized building system to facilitate contemporary bamboo housing construction in regions of economic constraint

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Modernizing the passing joint : a standardized building system to facilitate contemporary bamboo housing construction in regions of economic constraint Bentcheva, Yuliya D The thesis was inspired by the excellent mechanical properties of bamboo and its positive environmental effects. Despite its abundance and great qualities, the material has not been incorporated into the history of standard light frame wood construction and is therefore not used to its full potential, especially in regions of economic constraint in greatest need of housing structures. Can we design a light-frame construction system that allows for the non-standard nature of bamboo members and is inspired by the unique properties of the material? Can we reveal its contemporary uses and therefore allow for its cultural acceptance? The research investigates how a grid of members behaves as a system - incorporating imperfections and variations of individual elements. Along with the structural exploration, the work addresses the cultural misconception of bamboo as the "poor man's lumber" The exercises are aimed towards creating a housing unit that incorporates available materials into contemporary design elements. Thesis (M. Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, February 2012.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; "02-2012." Cataloged from student submitted PDF version of thesis.; Includes bibliographical references (p. 85).

Collapse analysis of unreinforced masonry domes and curving walls

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Collapse analysis of unreinforced masonry domes and curving walls Zessin, Jennifer Furstenau The safety and assessment of historic masonry structures continues to be a challenge for most analysts, especially for more complex buildings. Historic masonry structures have great cultural and economic value, but engineers have not examined the collapse modes for many masonry elements. This thesis examines the collapse of unreinforced masonry structures in response to large support displacements and constant horizontal ground accelerations. Two different structural forms are studied and collapse conditions are established for each. The aim of this research is to allow simple, but meaningful, analytical models and experimental results to inform each other in an effort to better define masonry collapse mechanisms. The first structural form to be analyzed is the masonry dome. For historical masonry domes, small outward movements of the supports will cause cracking and may lead to collapse. The critical span increase to cause collapse of a hemispherical dome is determined for domes with varying thicknesses using two small-scale physical models. In addition, the critical value of constant horizontal acceleration to cause collapse of a hemispherical dome is also examined, simulated by tilting the two domes on a plane. In both cases, a mechanism forms, rendering the dome unstable and collapse ensues. Simple analytical models, emphasizing the relationship between geometry and equilibrium, are able to accurately predict the failure limits and mechanisms. The second structural form to be analyzed is the curving masonry wall. In an effort to better understand the origins and perceived benefits of curving masonry walls, their stability is measured relative to the amount of curvature in the wall. The critical value of constant horizontal acceleration to cause collapse of a curving wall is determined using multiple equilibrium methods and compared with both full-scale and small-scale experiments for dry-stacked bricks. Based on these results, new limits for the stability of these structures are proposed. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2012.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (p. 176-182).

Desiccant dehumidification analysis

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Desiccant dehumidification analysis Xing, Hai-Yun Helen, 1976- Desiccant dehumidification has been given increasing interest in the air conditioning industry. Compared with conventional vapor compression air conditioning systems, desiccant dehumidification saves energy by separating humidity control from temperature control and also improves the indoor air quality as a good filter. This research explores the potential of applying desiccant dehumidification systems in buildings with less energy consumption. As the first step, the adsorption mechanism is explored and desiccant material properties are obtained based on a literature review. The heat and mass transfer in the desiccant - moist air system is well understood and modeled using both pseudo-gas-side controlled (PGC) transfer coefficients and semi-infinite transfer coefficients. Compared with experimental data, the model well predicts single processes while the prediction for cyclic processes is acceptable for practical applications. This model provides a useful tool for two purposes: analysis of desiccant unit 's performances and optimization of the design and operations of a unit. Based on the semi-infinite body theory, the semi-infinite model provides a way to simplify the solid-side diffusion resistance. A temperature control strategy is proposed to improve the mass transfer efficiency. A design in which the desiccant temperature is controlled in sections is tested using the model developed before. Simulations show that temperature control enhances mass transfer. Using the model, parametric analysis is conducted on a temperature-control led packed-bed desiccant unit. The effects on dehumidification performances of processing air mass flow rate, regeneration temperature and cycle time are studied. Parametric analysis gains insight into the correlations and interactions between different operation parameters. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2000.; Includes bibliographical references (p. 115-116).

Transformed materials : a material research center in Milan, Italy

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Transformed materials : a material research center in Milan, Italy Skerry, Nathaniel S. (Nathaniel Standish), 1971- [Transformed Materials] is an exploration into today's design methodologies of architecture production. The emergence of architectural form is questioned in relation to the temporal state of design intent and the physical material construct. At a time when there is an increased awareness of the current state of technology, material innovation and methods of fabrication, there are new speculations of what materiality is and can be. This thesis will propose an architecture that emerges through an exploration of the material concept that directly informs and expresses the fundamental ideas of the project. Building methods have changed widely over time, and are co-responsible for creating a dialog between functional requirements, technological invention, and material implication that reflects the current cultural state. Today's architectural products have in a sense reverted back to thin surfaces. Current cultural issues such as socioeconomic, environmental impact, transportability, efficiency, lightness, storability, technology, and mass production, have over time created a state of "thinness ". This project tries to offset the current trend of building by accepting the norms of architectural products, and reinventing their role within a contemporary language that explores more deeply the material qualities and properties associates with it. This thesis will use steel as the primary building material. Steel is a material that has become standardized in how it is shaped and formed, thus its ability to produce an architecture has been reduced purely to a dogmatiC approach of engineered solutions or preconceived results. Steel, is artificial by nature; if we suspend our preconceptions of steel, could the material be designed such that its role is critical in defining space, structure and program in a tectonic system? The area of research and examination will be focused on the design of a Material Research Center (mRC). located in Milan, Italy. Thesis (M. Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 2002.; Includes bibliographical references (p. 74-75).

Applications of sustainable technology to retrofits in urban areas

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Applications of sustainable technology to retrofits in urban areas Taylor, Paki (Paki A.), 1974- Energy Losses from old buildings comprise a significant percentage of the total residential energy consumption in the United States. Retrofitting buildings for conservation can greatly decrease the present energy demand and help prevent an eventual depletion of the world's natural resources. This investigation analyzes energy efficient measures applicable to retrofits in residential buildings in New England. The project estimates the likely performance of the latest sustainable technology and rates them according to cost-effectiveness for an average homeowner. Various retrofit measures and applications of sustainable technology are assessed according to relative importance and net savings. Improvements include a building envelope upgrade, an installation of a ground source heat pump and renewable energy systems. The analysis determines the energy savings relative to two base case models: a Cambridge Code and 1920s standard. The retrofit measures are analyzed at present and future energy rates. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2001.; Includes bibliographical references (p. 204-205).

Residential building energy analysis : development and uncertainty assessment of a simplified model

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Residential building energy analysis : development and uncertainty assessment of a simplified model Spindler, Henry C. (Henry Carlton), 1970- Effective design of energy-efficient buildings requires attention to energy issues during the preliminary stages of design. To aid in the early consideration of a building's future energy usage, a simplified building energy analysis model was developed. Using this model, a new computer program was written in C/C++ to calculate annual heat and cooling loads for residential buildings and to provide information about the relative importance of load contributions from the different building components. Estimates were made regarding the uncertainties of parameter inputs to the model, such as material properties, heat transfer coefficients and infiltration rates. The new computer program was used to determine the sensitivity of annual heat and cooling loads to model input uncertainties. From the results of these sensitivity studies, it was estimated that the overall uncertainties in the annual sensible heat and cooling load predictions amount to approximately ±30% and ±40%, respectively, for two buildings studied in Boston, Massachusetts. Further model simplification techniques were implemented that reduced annual load calculation times on a 180 MHz computer to about 8 and 12 seconds for a lightweight and massive building, respectively. The error introduced by these simplifications was approximately 4% and 10% for the annual sensible heat and cooling loads, well below the overall uncertainties in the load predictions. Comparison studies were performed with this new computer program and Energy-10. Overall, good agreement between the programs' annual load predictions was found. Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1998.; Includes bibliographical references (p. 163-165).

Energy conservation and thermal comfort in buildings in northern Pakistan

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Energy conservation and thermal comfort in buildings in northern Pakistan Sullivan, Gregory Patrick The Hunza Valley, a remote area of mountainous northern Pakistan, is undergoing rapid change culturally, socially, and architecturally. Many of these changes are linked to the exchange of information and commerce facilitated by the Karakoram Highway. This highway, completed in 1974, has allowed a culture and lifestyle dating back many of hundreds of years to be influenced by lower Pakistan and western cultures. Architecturally, these changes have led to the use of new, non-traditional, building material (concrete block and window glass) and new building designs which are climatically inappropriate and more consistent with the mild climate of lower Pakistan. This study examines these changes from an energy perspective in the homes and schools in and around Karimabad, a central village in the Hunza Valley. To assess baseline energy consumption, recorded indoor and outdoor temperature data for three homes and two schools were analyzed. These data were used with a steady state energy model to assess and compare energy consumption of a traditional and a modem home and assess energy conservation measures and design changes. The results showed a 30 percent reduction in heat loss in the traditional home compared to the modem home. This reduction is mostly due to the higher wall and roof thermal resistance values of the traditional home. Further insulation of the walls in both home types is recommended. In the case of the modem homes adding R-5 of rigid foam insulation is estimated to reduce heat loss by 46 percent, over the base case modem home, with a simple payback of 3.8 years. The use of windows is recommended on the south facing facade netting a simple payback of 3.9 years and the use of buried walls (into the north slope) and shared walls (cluster housing) were each estimated to save 17 percent over the standard modem home. Indigenous insulations were researched for use in homes and schools. Sawdust and straw were found to be the most practical and were used with a gluebinder to make 1.5"x 15"x 25" panels. These panels were tested in a flat screen thermal conductivity tester specifically built and calibrated for this study. The measured thermal resistance values were R-2.89/inch (+ /- 9.7 %) for the ... Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1995.; Includes bibliographical references (leaves 158-159).

Recommendations for the analysis and design of naturally ventilated buildings in urban areas

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Recommendations for the analysis and design of naturally ventilated buildings in urban areas Truong, Phan Hue The motivation behind this work was to obtain a better understanding of how a building's natural ventilation potential is affected by the complexities introduced by the urban environment. To this end, we have derived in detail the physical principles of wind- and buoyancy-driven natural ventilation for a standard apartment geometry, documented and analyzed the existing data on wind pressure coefficients in terms of urban morphological parameters, and examined the ow in the urban boundary layer and how it relates to the boundary layer at the rural site of the meteorological station. The information and understanding that emerged from this research has been assembled into a set of graphical methods and simple guidelines that can be applied by designers to the early design phases of natural ventilation projects in urban areas. These methods can be used to estimate indoor-outdoor temperature differences and air ow rates for several opening geometries. Our hope is for these methods to offer a good overview of how natural ventilation calculations can be applied to urban areas and to help resolve some of the main difficulties that a designer might encounter during this process. While the approach is primarily intended to inform decision-making during the beginning design stages, we imagine that, from applying it, designers will also acquire a more physical and intuitive understanding of how the forces of natural ventilation are altered in progressively denser urban sites and that this could also aid in the interpretation of results at the simulation stage. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2012.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (p. 119-121).

Design of structurally-sound masonry buildings using 3D static analysis

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Design of structurally-sound masonry buildings using 3D static analysis Whiting, Emily Jing Wei In the design of buildings, structural analysis is traditionally performed after the aesthetic design has been determined and has little in uence on the overall form. This thesis presents methods to integrate architectural design and structural analysis. While existing tools focus on providing an analysis of the stress state, the proposed methods focus on geometry and equilibrium to obtain forms that are more structurally sound. The feasibility of masonry structures is modeled using a novel penalty formulation, assuming a rigid-block behavior of masonry. Two methods were developed that apply this model of feasibility to structural optimization. In the first approach, structural feasibility is introduced into procedural modeling of buildings. A set of designated free parameters are automatically tuned to achieve structural feasibility constraints. It is demonstrated how this allows for more realistic structural models that can be interacted with in physical simulations. In the second approach, a closed form derivation of structural gradients is presented that measures the change in stability of a building with respect to geometry modifications. The method computes the gradient of structural feasibility constraints, parameterized by vertex modifications. The gradients are visualized as interaction tools, giving user-guidance for effectively modifying a structural design. User-controlled constraints, formulated as penalty functions, are incorporated so that the user can explore variations of structurally feasible designs. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2012.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (p. 95-100).

Variable volume architecture : expanding the boundary

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Variable volume architecture : expanding the boundary Saheba, Asheshh (Asheshh Mohit), 1972- Research into the creation of a Variable Volume Architecture is explored through a series of proposals and projects. An argument is established to develop the means and methods of achieving an architecture of transformation. The basis for developing such a stance is substantiated and clarified with the act of probing into constructs of various scales. The design and manufacturing of a full scale prototype is explored to bring bearing on the physical resolution of the proposal. The device is an acknowledgment of potential applications and uses. The material, spatial, and structural nature of the propositions are articulated and examined throughout the investigation. The morphology of the concepts presented is derived to bring clarity to issues towards an endeavor for creating a responsive architectural landscape. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2001.; Includes bibliographical references (p. [88]-89).

A multilateral design methodology for development contexts : a framework for the Dharavi potters

2022-01-13T07:54:12Z

A multilateral design methodology for development contexts : a framework for the Dharavi potters Razvi, Amina S. (Amina Sultana), 1975- The migration from rural areas to urban environments, and the continuous growth of the current population has caused an increasing shortage of low-in come urban housing in developing countries. In addition, the high cost of available housing has driven many in the lower income groups into squatter settlements in and along the periphery of urban developments. These squatter settlements are often the result of ineffectual and dysfunctional social and economic policy, compromised structures of governance, corrupt land markets, lack of equitable and humane regulation, and improper and inefficient finance scenarios. While poverty has many dimensions, urban poverty often has a broader meaning of cumulative deprivation, characterized by: squalid living conditions; risks to life and health from poor sanitation, air pollution, crime and violence, traffic accidents, and natural disasters; and the breakdown of traditional family and community safety nets. Rapid population increases within urban areas, crumbling infrastructure, growing inequalities between rich and poor, and insufficient urban services point to the need for a reevaluation of current models of urban development. Through an investigation of a multi-disciplinary approach to development, this project will identify the difficulties and potentials within the context of development in order to augment current design, planning, financing, and construction knowledge towards the creation of viable and sustainable architecture. The Khumbar Wada potters' community in Dharavi, Mumbai will be utilized to illustrate the potential for multi lateral approaches to go beyond the rhetoric that has compromised the discussion of architecture and its relationship to development work. The design will address development strategies and construction processes that express local conditions within the urban, architectural, and tectonic scales. Through the investigation and implementation of architectural infrastructure, the design will alleviate environmental, economic, and political constraints while accommodating local values. A potters' workshop will serve to illustrate the potential of a multi lateral design methodology. This thesis aims to suggest a framework for decision-making that can be used across various sectors and at multiple scales and the physical implementation of infrastructure that allows for the creation of more humane environments. Thesis (M.Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 2002.; Page 83 blank.; Includes bibliographical references (p. 80-82).

Minimizing electricity costs with an auxiliary generator using stochastic programming

2022-01-13T07:54:29Z

Minimizing electricity costs with an auxiliary generator using stochastic programming Rafiuly, Paul, 1976- This thesis addresses the problem of minimizing a facility's electricity costs by generating optimal responses using an auxiliary generator as the parameter of the control systems. The-goal of the thesis is to find an optimization method that can cope with the uncertainty in the building load while also handles the complex electricity price structures. The building load is the random factor of the stochastic problem and is composed of the weather load and the occupancy load. Several optimization techniques such as Dynamic Programming and Linear Programming (deterministic optimization) are looked at. Stochastic Programming using Nested Bender's Decomposition method is chosen and studied to solve the optimization problem. Stochastic Programming, which is a hybrid of Dynamic Programming and Linear Programming, is used because it can cope with the complex electricity price structures and the uncertainty of the building load while avoiding an explosion in the number of states. However, the method is not suitable for our problem, which is a Mixed Integer Programming problem. Moreover, the random sampling adds some limitations on the method. In addition, the ~high memory requirement and the extensive computational time prohibit the method from being used for a long planning period. Hence, a new control system, which is the combination of Stochastic Programming and Linear Programming, is proposed. The key of this proposed method is the reduction of the problem into a two-stage stochastic problem. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000.; Includes bibliographical references (p. 95-97).

A framework for sustainable buildings : an application to China

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A framework for sustainable buildings : an application to China Ospelt, Christoph, 1970- A framework has been established to discuss the different topics of Sustainability in the context of buildings. The framework includes the dimensions of time and space and the dimensions of ecology, society, and economy. Buildings are shown to have a substantial share on the total environmental and human health impact of an economy. In an energy efficient building, the impact embodied in the building construction can be dominant over the impacts from building operation. Life cycle assessment is a tool that provides the means for establishing quantitative indicators of sustainability. The different existing impact assessment methods used to aggregate hundreds of different pollutant releases and resource consumption into a few useful indicators are analyzed. Ways of integrating these indicators into the design process are shown and existing design tools and building assessment methods are discussed. A case study on Chinese buildings shows the potential for energy conservation measures as the primary means of directing the Chinese building stock towards a more sustainable path. Developed countries will have to lower their impact on global ecosystems substantially in order to allow countries like China to approach our standard of living. Taking into account the slow turn-over rate of buildings, new buildings have to be at least four times more environmentally effective on a lifetime basis. The necessary data on building materials needs to be made available. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 1999.; Includes bibliographical references (p. 149-156).

Scale model studies of displacement ventilation

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Scale model studies of displacement ventilation Okutan, Galip Mehmet Displacement ventilation is an air conditioning method that provides conditioned air to indoor environments with the goal to improve air quality while reducing energy consumption. This study investigates the performance of displacement ventilation systems in open plan office environments, focusing on vertical temperature stratification. It explores the possibility of improving the performance of these systems by reducing the temperature stratification at lower levels and allowing them to operate with high cooling loads without exceeding thermal comfort limits. An experimental setup consisting of a scale model of an open plan office room and equipment necessary to provide the experimental conditions was designed and constructed. Steady state experiments on displacement ventilation were conducted. The experiments simulated a variety of cases in terms of heat gain per area, air supply flow rate and slow mixing at lower levels. Temperature distributions in the model and fluid flow rates were measured. Flow visualization was performed to investigate the flow patterns in the office room. The vertical temperature profiles for the considered cases were not linear. The vertical temperature stratification increased when the heat gain in the office increased. It was within the comfort limits for all simulated cases, except the case with the maximum heat gain (38W/m2). The introduction of slow mixing at lower levels decreased the temperature differential in all experiments. This effect of slow mixing was more pronounced at lower heights. This suggested that displacement ventilation may accommodate higher cooling loads if slow mixing at the lower levels is provided. Flow visualization results indicated that the height of the stratification was about 1m above the floor. The plumes over the heat sources had different characteristics, implying the possible importance of the size, shape and spatial distribution of the heat sources. Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1995.; Includes bibliographical references (leaves 144-146).

Heat pipe dehumidification for supermarket energy savings

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Heat pipe dehumidification for supermarket energy savings Oliver, Eric M. (Eric Michael) This thesis examines the possibility of using a heat pipe installed in the air conditioning unit of a supermarket to increase the level of dehumidification of the inside air. This dehumidification is expected to reduce the energy consumption of the refrigeration system due to an improved efficiency of the heat transfer at the display case. This increase in efficiency will be due to reduced frost buildup on the refrigeration coils. Chapter two includes a physical and psychometric analysis of the heat pipe, proving that for any system where direct evaporation dehumidification is used, at any given time when dehumidification is being performed, the addition of a heat pipe will increase the amount of moisture being removed by the cooling coil. For this thesis, a heat pipe was installed in a supermarket in Worcester, Massachusetts. Over a period of the summer from the beginning of June to the end of October, various air temperatures and relative humidities, refrigeration line temperatures, pressures, and mass flows, and compressor power consumption were monitored for fifteen minute periods. The monitoring period included two months before the installation and three months after the installation to determine changes in the air system and refrigeration system due to the presence of the heat pipe. Chapters two through five describe the equipment, site and strategy used in the analysis. Chapter six describes the results of the monitoring, and Chapters seven and eight give the results of the air system and refrigeration system models. The systems were modelled using monitored data and engineering equations to predict humidity levels and power consumption based on ambient conditions. The analysis was unique in that a heat pipe application had never been previously studied in a Northeast location, since the mild summers made dehumidification less of an issue than in Southern states. This study was also considerably more in depth than previous studies (summarized in Chapter 2), for which savings estimates do not account for large potential errors. This study concluded that potential savings estimates (0-8% reduction in supply air humidity, -1 % reduction in refrigeration power) were within statistical error (9% for specific humidity, 4% for refrigeration power), and therefore inconclusive. Further studies with superior equipment and modelling strategies are needed to substantiate heat pipe dehumidification. Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1994.; Includes bibliographical references (leaves 178-179).

Probing the black box : experiments in design and design education

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Probing the black box : experiments in design and design education Mulvey, Christopher P. (Christopher Paul), 1975- Conventional analysis and design methods based on preexisting methods and assumptions preconditions and limits the designer's level of engagement with the specific context that is under investigation. A structural analysis is concerned with the disclosure of [subconscious] tendencies and agendas from within a form or site. This thesis develops methods that facilitate the organization and evaluation of 'design information' gathered from a structural analysis. The methodologies developed in this thesis place an equal emphasis on excavating the logic and tendencies of both the physical context and the logic of the conceptual structuring of the designer's processes. This approach acknowledges that each situation offers its own specific truths and that each project needs to readdress the issue as to what constitutes the discipline of architecture. The methodologies developed in this thesis analyze the site through the lens of events as a means to suspend preconceptions and investigate the tendencies of the designer. It takes as axiom that some thoughts and intentions cannot be reached frontally, but rather require analogies, metaphors or other such strategies to uncover the subconscious meaning. The design methodology developed in this research is a proposal for such a strategy. This suspension allows for the emergence of intuitions and strategies directly from site and the context. These methods also become a means to elicit, record and classify the 'conceptual schema' or the structure of the designer's thought. They attempt, in a constructivist manner, to aid the students in clarifying their thought processes. This thesis will explore the mapping of concepts and approaches clearly and externally as a means to create an intellectual space for the designer to work within. This space becomes a way to test and evaluate ideas, and intuitions within a 'conversational approach'. This approach defines the role of the designer as both writer and reader. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2000.; Includes bibliographical references (leaves 75-77).

Improving the quality and transparency of building life cycle assessment

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Improving the quality and transparency of building life cycle assessment Hsu, Sophia Lisbeth Life cycle assessment, or LCA, is a powerful method for measuring and reducing a building's environmental impacts. Its widespread adoption among designers would allow the environmental component of sustainability to gain more traction in design philosophy and client goals. Currently, the stakeholders in building design-both design professionals and clients-have few resources for proper LCA education and use, and there are no common metrics agreed upon for reporting the results of LCAs for buildings. This thesis assesses the strengths and weaknesses of resources available to design practitioners for performing LCA, including a pilot credit in the United States Green Building Council's Leadership in Energy and Environmental Design ratings system. A case study performs an LCA comparing two structural materials in an office building. The study aims to be as transparent and repeatable as possible, in order to set a good example on which to model future building LCAs. Based on the critical review of LCA resources and the lessons learned from the case study, eight key points are proposed for improving the quality and transparency of building life cycle assessment projects. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2011.; Cataloged from PDF version of thesis.; Includes bibliographical references (p. 54-60).

Lighting a building with a single bulb : toward a system for illumination in the 21st c.; or, A centralized illumination system for the efficient decoupling and recovery of lighting related heat

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Lighting a building with a single bulb : toward a system for illumination in the 21st c.; or, A centralized illumination system for the efficient decoupling and recovery of lighting related heat Levens, Kurt Antony, 1961- Piping light represents the first tenable method for recovery and reutilization of lighting related heat. It can do this by preserving the energy generated at the lamp as radiative, departing from precedent and avoiding absorption of and re-emission of radiant heat as convection and conduction. Within thermodynamic limits, the radiant heat generated by an electric lamp or the sun is available for optical concentration and for reconstitution as a high thermodynamic quality power reservoir. Piping light from a large central lamp facilitates the decoupling of lighting related heat at the source, and also means that the efficiency of one central fixture can be stringently optimized instead of the multitude of fixtures it replaces in buildings. Luminous efficacy for a full-spectrum lamp decoupled of its infrared can be shown to approach theoretical limits of 250 lumens/watt. UV generated by the lamp, if coupled along with the illumination into the transport fibers, can be converted into visible radiation at the emitting end of the fiber, supplementing the light output. Fiber optics are used to carry information over long distances (actually encoded pulses of radiative IR), but certain fiber optics can carry tremendous amounts of energy. As fiber optics become more and more plentiful in telecommunications, their prices will come down. Cost and operating expense studies included in the final chapter of this thesis indicate that a large single source with light that is efficiently coupled and piped throughout a building's interior could reduce electric light consumption to one-fourth, and that even at current fiber pricing levels some systems can be competitive in initial cost to conventional lighting. Certain aspects of centralization suggest further reductions in cost and operating expenses such as centralized, instead of localized, relamping and cleaning, and eliminated requirements for thermal, electrical, and structural hardware at room fixture locations. The economic and technical feasibility of a central system depends on the simultaneous minimization of fiber aperture area and energy losses. Thermodynamically, the concentration of light for transport cannot surpass the energy density of the source. So such a system employs, at best, an optical process that preserves the extent of the source. That is, a high brightness source must be used to drive the system, regardless of the lamp's lumen output. High brightness lamps, then, can be viewed as an alternative to high efficacy lamps for increasing the energy performance of lighting systems in buildings. This thesis anticipates the existence of high brightness, high lumen lamps. The sun's 10,000 footcandles in peak conditions can be a potent contributor to the energy efficacy of buildings if a collection and utilization strategy is properly devised. At 100 sq. ft of available illumination for each sq. ft of collected sunlight, a scenario including simultaneous collection and distribution of electric light and heat and sunlight and solar heat in a building could reduce to near zero the energy consumed for lighting during peak sun conditions. Studies in this thesis indicate that an economically driven future role of solar energy in the lighting, heating, and cooling of buildings could very well revolve around keeping sunlight in the form of illumination and sunheat in the form of radiative heat, instead of converting both into electricity via photovoltaics and reconversion of this electricity back into electric light. Conventional lighting is an inefficient process, essentially using heat sources for the light they provide. Not only is lighting related electricity generating predominantly waste heat, this heat must be removed from the building's envelope by an additional input of energy. Even energy saving fluorescent lamps and fixtures produce at least 80% heat. This might serve to explain why 30% of the country's electricity is consumed by lighting. This thesis proposes a method for decoupling and recovery of lighting related heat, and transporting light in lieu of electricity to lighting fixtures (Chapters 2 and 6). Each of the optical components that would comprise such a system is examined. Chapter 7 investigates the radiation source. Chapter 8 develops the source reflector which will direct the source's radiative output in a particular direction. Chapter 9 studies a mirror that will separate the source's radiation beam into a light beam and a heat beam for subsequent processing. Chapter 10 looks at the heat collector that will convert the heat beam into a usable high-temperature power reservoir. Chapter 11 devises the light collector/ concentrator that will facilitate coupling of light energy into a fiber optic transport network. Chapter 12 assembles the constituent components into central modules. Chapter 5 surveys the light transport media, in particular fiber optics and Prism Optical Light Guide, for suitability to building lighting applications. The exact method of solar couplature is not introduced. Sample energy efficiency comparisons, cost and payback scenarios, implementation issues and concepts for room emitters are included in chapter 13. Related concepts for a transparent concentrating solar collector for use as a window or skylight, and a solar concentrating wall are disclosed in the conclusory chapter. Material included in this thesis has been patented by MIT. The usage of such material for any commercial means requires a licensing agreement. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1997.; Includes bibliographical references (leaves 227-229).

Applied change of mean detection techniques for HVAC fault detection and diagnosis and power monitoring

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Applied change of mean detection techniques for HVAC fault detection and diagnosis and power monitoring Hill, Roger Owen A signal processing technique, the detection of abrupt changes in a time-series signal, is implemented with two different applications related to energy use in buildings. The first application is a signal pre-processor for an advanced electric power monitor, the Nonintrusive Load Monitor (NILM), which is being developed by researchers at the Massachusetts Institute of Technology. A variant form of the generalized likelihood ratio (GLR) change-detection algorithm is determined to be appropriate for detecting power transients which are used by the NILM to uniquely identify the start-up of electric end-uses. An extension of the GLR change-detection technique is used with a second application, fault detection and diagnosis in building heating ventilation and air-conditioning (HVAC) systems. The method developed here analyzes the transient behavior of HVAC sensors to define conditions of correct operation of a computer simulated constant air volume HVAC sub-system. Simulated faults in a water-to-air heat exchanger (coil fouling and a leaky valve) are introduced into the computer model. GLR-based analysis of the transients of the faulted HVAC system is used to uniquely define the faulty state. The fault detection method's sensitivity to input parameters is explored and further avenues for research with this method are suggested. Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1995.; Includes bibliographical references (leaves [159]-[161]).

A scale model study of displacement ventilation with chilled ceilings

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A scale model study of displacement ventilation with chilled ceilings Holden, Katherine J. A. (Katherine Joan Adrienne) Displacement ventilation is a form of air-conditioning which provides good air quality and some energy savings. The air quality is better than for a conventional mixed ventilation system. The maximum amount of cooling that displacement ventilation can provide whilst maintaining a comfortable space is between 25 and 40 W/m2. Chilled ceilings can be added to increase the cooling capacity of the system. A scale model study was carried out to determine comfort levels at different conditions, to establish maximum cooling loads and to observe flow patterns in a typical office room with displacement ventilation and a chilled ceiling. Refrigerant R114 was used as the scaling fluid and an existing test box was used as the model room. Heat sources were simulated using electric resistances in aluminum enclosures. A gas and a water circuit were built to supply ventilation and cooling to the room. Flow visualization was carried out by injecting refrigerant laden with ammonium chloride smoke into the supply point. The smoke was lit by a spotlight shone between two pieces of cardboard and images were taken using a video camera. The results showed that for displacement ventilation alone, the temperature distribution was within stringent comfort levels for heat loads up to 25 W/m2 with an air change rate of 7.5. When a chilled ceiling was added, up to 40 W/m2 could be cooled within comfort levels. The refrigerant was radiatively absorbing, so the radiation cooling from the ceiling was reduced. Therefore, this maximum cooling load is probably an underestimate. Some displacement occurred at low levels for this cooling load, which indicated good air quality, but it was below the breathing zone. At higher loads, the flow appeared to be mixed. Therefore, the benefit of enhanced air quality with displacement ventilation was lost when a chilled ceiling was added. The use of a scale model allowed the study of ventilation systems without building a full scale room. It was of limited use for this study because the heat transfer by radiation could not be modelled correctly with this refrigerant. Further experiments could be carried out with lower supply air rates. The experiments could be improved by ensuring more accurate measurement of the water and gas flow rates and temperatures, reducing heat losses. Flow visualization could be improved by injecting smoke at different points within the room and by using a stronger, more focused plane of light. The apparatus could be used for future work on heat transfer that does not involve a significant amount of radiation. It is recommended that a more leak-tight box with a greater height is built and a more environmentally friendly refrigerant is used. Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1995.; Includes bibliographical references (p. 81-84).

A re-connection : modeling built works after natural systems

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A re-connection : modeling built works after natural systems Griffith, Laurie Anne, 1973- The constructed world is full of built works that consume energy and emit unusable waste. This is fostered by the act of 'masking' the true situation and the lack of embedded feedback, associated with the destructive operations of centralized, unintelligent systems. This inefficient organization encourages the destructive processes of production and consumption to remain unaccountable, broadening the disparity between the built environment and the natural ecosystem. Similarly, there is an increasing social disconnection between people and the natural environment, signified by less time spent outdoors and particular advancements in building technology. In order to counter this trend, this thesis takes the position that it is imperative to become more ecologically and socially interconnected. To accomplish this, it is necessary to draw from the efficiency and interdependency of the natural environment; therefore, built systems must model themselves after natural systems. In response to this need, I have proposed built works as net producers of energy, inherently giving to the livelihood of the whole, and partiCipating in an expressed, dynamic built world eco-system/place. This intention was initially addressed by establishing criteria to re-define the relationships between existing built works and energy production, motivated by the notions of a whole-systems methodology <3.1>, renewable energy production and recycling <3.2>, and social involvement and influence <3.3>. The design intention was then executed by focusing on both energy flows and available renewable energy sources, coupled with a process of un-masking and re-connecting in order to heighten awareness, respect, and delight in the context of the built environment. As the set of criteria was conceived, a 'typical' urban site was chosen on which to integrate and test these intentions. The following design exploration addresses the means employed to transform the existing site into an energy producing system of entities, and an ecologically and SOCially interconnected built place. Thesis (M.Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 2001.; Some pages folded.; Includes bibliographical references (p. 123-125).

Development of straw insulation board : fabrication methods, structure, thermal performance

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Development of straw insulation board : fabrication methods, structure, thermal performance Harvey, Henry S. (Henry Stimson) Insulation board is being fabricated and tested for use in developing countries. It is made at a low density, in the area of 5 to 10 pounds per cubic foot (80 to 160 kilograms per cubic meter), and has good thermal properties for an air based insulation, meaning R3 to R4 per inch (Btu-in/ hr-ft2-°F)-, or a conductivity of .048 to .036 W/m-K. The initial effort is to produce a straw insulation board suitable for northern Pakistan, where we are studying the needs and construction of schools and houses. Some type of rigid insulation is needed, as opposed to loose fill, because the buildings have solid masonry walls without an air gap. These boards will be suitable for other developing countries as well The initial survey of possible methods included 1) containing the straw in panels with wire and battens, 2) pulping the straw, and 3) binding with adhesive. In this latter category starch, PVA and sodium silicate were tried as adhesive using uncut and shredded straw, with various methods of application such as spraying, foaming, and dipping, at various adhesive loading rates. Small samples were formed at a range of densities to test structural and thermal properties. This survey suggested that all three of these approaches can succeed structurally and thermally, but that competing economically with existing insulation board is difficult. For boards with binder, the adhesive efficiency was poor. In the final phase of the project, a batch of boards was made at ICI Polyurethane's North American research and development facility, using methane di-isocyanate as the binder. The boards, made at a range of densities and resin contents, and using straw with and without the fine particles, were tested thermally and structurally at MIT. Good mechanical properties were obtained at resin contents as low as 2% by weight. At densities of 8 and 10 pounds per cubic foot (pcf), these boards have R values of 3.7 and 3.45 per inch, respectively. The pressure required to compress the 10 pcf boards to 10% of their original thickness is approximately 15 pounds per square inch (psi), and the modulus of rupture in bending is in the range of 50 psi. Removing the fine particles from the straw improved board strength markedly. These boards at a density of 10 pcf and 2 to 4 % resin content have an estimated materials cost of 2 [cents] per insulating unit (R-ft2), substantially less than either the cost of the expanded polystyrene available in Pakistan, or the retail cost of any rigid board insulation sold in North America. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 1997.; Includes bibliographical references (p. 66-69).

Adaptable structural surfaces

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Adaptable structural surfaces Foeldeak, Hans-Michael, 1975- The framework for this thesis are the lightweight constructions that have been developed during the 20th century. As part of this thesis, a prototype for a column has been developed, that is a hybrid construction out of a lattice and surface structure. It follows the principle of adaptability instead of rigidity through taking advantage of the distributive qualities of weaker materials. Tlu·ough this development as well as through the study of the history of lightweight structures, a set of principles has been developed that can serve as the basis to a different approach to structures. This approach deals with questions of how structures can support architectural ideas without becoming the center of focus themselves, how structures can be applied in a topical way in today's postindustrial situation, and how architects can deal with a special field within architecture and how their way of working can be complimentary to engineers' and scientists' way of working. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2003.; Includes bibliographical references (leaves 55-57).

Modeling the water consumption of Singapore using system dynamics

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Modeling the water consumption of Singapore using system dynamics Welling, Karen Noiva Water resources are essential to life, and in urban areas, the high demand density and finite local resources often engender conditions of relative water scarcity. To overcome this scarcity, governments intensify infrastructure and project demand into the future. Growth in the economy, population, and affluence of cities increase water demand, and water demand for many cities will increase into the future, requiring additional investments in water infrastructure. More sustainable policies for water will require capping socioeconomic water demand and reducing the associated demand for non-renewable energy and material resources. The thesis consists of the formulation of a System Dynamics model to replicate historic trends in water consumption for the growing city of Singapore. The goal of the model is to provide a platform for assessing socioeconomic demand trends relative to current water resources and water management policies and for examining how changes in climate and infrastructure costs might impact water availability over time. The model was calibrated to historical behavior and scenarios examined the vulnerability of supply to changing demand, climate, and cost. The outcome is a qualitative dynamic assessment of the circumstances under which Singapore's current policies allow them to meet their goals. Singapore was chosen as the case study to demonstrate the methodology, but in the future, the model will be applied to other cities to develop a typology of cities relative to water resources. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2011.; Cataloged from PDF version of thesis.; Includes bibliographical references (p. 217-226).

Designing for forces : an early-stage design program for axial-force structures

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Designing for forces : an early-stage design program for axial-force structures Jordan, Alexander D. W. (Alexander David Weigert) Structures that carry most of their load through the axial forces of tension or compression are more materially efficient than standard structures. However, they are not as straightforward to design since the forces in the structure depend on shape. The traditional method of form finding for such axial force structures is to create physical hanging models. These models are slow to produce and difficult to measure. Few digital design aids exist for designing axial force structures, and those that do tend to be for optimization or analysis, not necessarily for early stage design. In addition, they tend to lack desired functionality for a design program, and also tend focus on creating forms without considering engineering functionality. Since form and forces are so intertwined in axial-force structures, consideration of both in the early stages of design is desirable and is not fully addressed by existing programs. This thesis presents a new early stage design program, ForceDesigner, which improves the functionality of earlier programs and facilitates design by both architects and engineers. It builds on earlier design programs that use the particle spring system for creating digital hanging models, implementing the system in Processing and Java. The result is a program with a number of novel functions that allows designers interested in both form and forces to more quickly and easily create an unlimited number of efficient structures. Thesis (S.B. in Art and Design)--Massachusetts Institute of Technology, Dept. of Architecture, 2011.; Cataloged from PDF version of thesis.; Includes bibliographical references (p. 64).

Methods to improve school design in Sierra Leone

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Methods to improve school design in Sierra Leone Clonts, Kelly A Most schools in Sierra Leone are constructed using a standard design with little variation from building to building. They are relatively high-cost and have poor ventilation, lighting and thermal comfort. In January 2010, thirteen primary schools in Sierra Leone were analyzed in order to identify design changes that will improve performance and reduce costs. One struggle that this analysis revealed is that construction methods have not changed for decades, as local builders resist changes in the current design. This thesis aims to explain small-scale alterations for primary school buildings in Sierra Leone and list the impact on daylighting and thermal comfort performance for each alteration. For each design alteration, the daylight performance, air flow, and thermal comfort of the new design are compared to the standard design. The overall goal of this thesis is to create guidelines that can be used to reduce the risk of design changes and improve the performance of schools without raising costs. Thesis (S.B. in Art and Design)--Massachusetts Institute of Technology, Dept. of Architecture, 2011.; Cataloged from PDF version of thesis.; Includes bibliographical references (p. 80-83).

BridgeGreen : bridging the disconnect between design professionals and resources fro environmentally, socially, and economically responsive architecture

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BridgeGreen : bridging the disconnect between design professionals and resources fro environmentally, socially, and economically responsive architecture Elbaum, Meredith Sue, 1975- Sustainable design, whether referred to as green, high performing, responsible, or environmentally, socially, and economically responsive architecture, is influencing the global building industry. Most major firms of architecture including Gensler, Hellmuth, Obata, Kassabaum, and Skidmore Owings and Merrill, are designing green buildings. Growth in programs like Leadership in Energy and Environmental Design (LEED) and Building Research Establishment Environmental Assessment Method (BREEAM), the United States and Great Britain's respective green building rating programs, illustrate the rising trend to go "green" within the industry. There are many obstacles facing the growth of the green building industry. While most architects admit green architecture is non-dismissable, because of these obstacles, they continue to design a majority of buildings with little consideration for environmental impact. Many of these obstacles can be overcome with the right resources. Resources already exist to assist designers in lessening the environmental impact of buildings. However, there is a clear disconnect between available resources and the design professionals they target. Professionals, for the most part, do not know what these tools are, where to find them, who should use them, and when to use them in the design process. This thesis bridges this disconnect between design professionals and available resources. It suggests appropriate strategies for a prescribed design phase based upon environmental impact, building system, and design professional, and presents a list of resources for each strategy. Its aim is to disseminate resources to the appropriate professionals so that they can make informed decisions during the design process relative to environmental impact. Manifested in the form of an interactive web-based tool, it lends itself to future development. An increase in informed decisions will inevitably decrease the negative impact buildings have on the environment. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2003.; Includes bibliographical references (p. 100-105).

Financial analysis of energy-efficient façade systems for application in commercial office developments

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Financial analysis of energy-efficient façade systems for application in commercial office developments Dee, Rocelyn Sy, 1976- Advocates for sustainable development have been campaigning for the implementation of green features in developments. New and high-technology energy-efficient technologies, such as photovoltaic cells and double skin façades, have been difficult to incorporate in developments even though they carry with them the promise of better performance and greater environmental impact. While some proponents of green development would have us believe that energy-efficient technologies are worthwhile investments, the truth is that the benefits do not always outweigh the costs. The key is promoting mass applications of these technologies is by providing an instrument for decision-makers to understand performance implications of building systems choices as represented by financial costs and benefits. It is through this holistic comprehension, as opposed to a dissection of development components, that risk perception can be mitigated and well-informed decisions can be made. This proposal presents a financial analysis of the implications of different façade. These systems will be applied to a similar base building with same performance specifications for a controlled comparison. The building type will be limited to commercial offices. It is important to note that the objective is not to arrive at an absolute cost valuation, but rather to cognize the relative efficiencies of one against the other. By using currency-based values as a representation of advantages and disadvantages, we are communicating in a common language familiar to decision-makers. This thesis hopes to achieve a better understanding of the efficiencies, or inefficiencies, of using high-technology façades. While the primary goal is to achieve a more accurate picture of the financial performances of high-technology energy efficient systems against conventional systems, the analysis will also give us a good understanding as to what barriers stand in the way, and what conditions have to exist for them to achieve widespread application. In the end, this could be the more valuable contribution. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2002.; Includes bibliographical references (116-120).

Natural ventilation possibilities for buildings in the United States

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Natural ventilation possibilities for buildings in the United States Dean, Brian N. (Brian Nathan), 1974- In the United States, many of the commercial buildings built in the last few decades are completely mechanically air conditioned, without the capability to use natural ventilation. This habit has occurred in building designs since the designers do not have the tools to understand the impact of using natural ventilation as an option in conditioning a building. Research has been conducted to create a better understanding of how natural ventilation can be used successfully in building designs. First, understanding the buildings that currently use natural ventilation and secondly by analyzing how buildings can operate in different climates. It is important in the building design industry to know the feasibility of designs, and is therefore important to see buildings that have used natural ventilation techniques. It is also important in the building design industry to know if the natural ventilation techniques that have been used, can be used in the climate that a building needs to be designed for. It was determined that increased airflow through natural means can significantly enhance the functionality of buildings in the United States. Throughout the United States there are numerous hours when outdoor conditions suggest using natural ventilation for a primary cooling system. Natural ventilation can help a building maintain comfort for the occupants, reduce energy usage, reduce cooling equipment size and increase indoor air quality. With the use of a natural ventilation design tool, designers can understand the impact that each of the buildings major features has on the overall comfort or energy required to make it comfortable. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2001.; "June 2001."; Includes bibliographical references (p. 171-172).

Material impacts on operational energy usage

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Material impacts on operational energy usage Love, Andrea, S.M. Massachusetts Institute of Technology Decisions regarding materials and construction of a building are made all the time in the architectural process, but thought is not always given to how those choices may affect the buildings ultimate energy usage and the impact they may have on climate change. This thesis focuses on concrete structures and how the thermal mass and the thermal resistivity influence energy usage. The investigation was done looking at large commercial office buildings in the climates of Phoenix and Chicago. A comparison was conducted between a steel frame and concrete frame structure, showing how the differing thermal mass impact energy usage. An investigation was also undertaken to better understand thermal bridging in concrete commercial building envelopes and the impact they have. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2011.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student submitted PDF version of thesis.; Includes bibliographical references (p. 96-103).

Sustainability in architecture

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Sustainability in architecture Cordero, Elizabeth, 1959- Current standard practice in architecture does not take into account the external societal costs that a building creates. To understand the total consequences of a building, one must consider all of the ecological and human health factors involved for a specific project and site. The aim of sustainable architecture is to construct a well-designed building and site environment that is healthy for the occupants, has minimal undesirable impact upon the environment, is effective in the use of natural resources, and is economical and durable. Although tangible impacts are visible only after construction begins, decisions made on the drawing board have long-term environmental consequences. The objective of this thesis is to present the information and tools available to the architect to create a sustainable project. With these tools, the architect can meet the challenges of sustainable design with an informed decision making process. This thesis defines sustainability as it applies to architecture, compares environmental performance rating systems and guidelines, discusses simulation, design, and life cycle analysis tools, outlines specific green building strategies, devises a methodology for prioritization, and summarizes design and construction procedures that incorporate these green concepts into the building process. The thesis finishes with a complete project plan that, when incorporated, will promote the realization of sustainable buildings. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2001.; Includes bibliographical references (p. 189-197).

Straw insulation materials to address heating fuel requirements, thermal comfort, and natural resource depletion in developing regions

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Straw insulation materials to address heating fuel requirements, thermal comfort, and natural resource depletion in developing regions Charlson, Joseph Arons In modem society, major stresses are placed on the natural environment in an attempt to make the location comfortable for the human occupants. For many developing regions with cold winters such as northern Pakistan, new building construction has been driven by structural and economic criteria. Thermal comfort can be improved, heating fuel requirements can be reduced, and degradation of the natural environment can be mitigated by improving the thermal performance of these buildings. This thesis presents strong evidence for the benefits of thermal insulation and presents an optimal solution for producing that insulation in a sustainable and cost-competitive manner. Using Polymeric Methylene Diisocyanate as a binder, we were able to develop a formula for low density, structurally sound, straw based insulation board. The fabrication process involves the spraying of isocyanate onto an agricultural furnish of mixed fiber lengths in a rotating drum. The process appears to be one that could be used in developing regions. It is likely that this board can be manufactured well below the cost of competing insulation board products on a unit thermal resistance basis. Forty-one experimental boards were fabricated. The thermal, structural, and economic characteristics of these boards have been tested and analyzed. A formula has been developed for an optimized solution based on binder load, fiber size concentrations, density, and economic cost. The optimal boards meet or exceed all of our product design specifications. The optimal insulation placement scenarios for community-built school buildings are explored through the use of a dynamic building thermal modeling software, SERI-RES. The work described in this thesis provides a strong foundation for moving ahead and improving the thermal performance of the schools. Installation of insulation will improve thermal comfort in schools that continue to be unheated or under-heated. For those schools that are more fully heated, insulation will reduce fuel use at no penalty in thermal comfort. Improved thermal comfort will extend the use of schools in winter and payback periods are of reasonable duration, from two to four years for heated schools. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 1997.; "February 1997."; Includes bibliographical references (p. 252-253).

Natural ventilation generates building form

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Natural ventilation generates building form Chen, Shaw-Bing Natural ventilation is an efficient design strategy for thermal comfort in hot and humid climates. The building forms can generate different pressures and temperatures to induce natural ventilation. This thesis develops a methodology that uses a computational fluid dynamics (CFD) program. The purpose of the CFD program is to assist architects to design optimum building form for natural ventilation. The design of a cottage in Miami, Florida demonstrates the application of this methodology. The first phase of this methodology is to create an input file for the CFD program. The input file uses wind velocity, wind direction, and air temperature of the site to simulate the weather. Different weather conditions can be generated through modification of the first input file. The second phase of this methodology is to develop building forms. The CFD programs can simulate airflow in different building forms by changing the building geometry in the input files. The program calculates the airflow pattern, velocity, and temperature for different forms. The printouts of the simulations allow architects to understand the airflow behavior in spaces with different forms. This thesis also uses the CFD program to study variance between the proposed and the actual results of a design. As demonstrated in a sports museum in Washington, DC, this case study clearly displays a difference between the intentions of the architect and the results of CFD calculation. Some problems appear in developing CFD models. However, when the input files are correctly defined, and the calculations converge, very few computational problems appear in developing building forms. Therefore, architects can easily use the CFD programs to develop building form after the input files are correctly defined. Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1996.; Includes bibliographical references (leaves 149-151).

Mainstreaming straw as a construction material : understanding the future of bio-based architectural materials

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Mainstreaming straw as a construction material : understanding the future of bio-based architectural materials Carbone, Christopher M. (Christopher Martin), 1975- There is a current trend in design and construction towards the use of distinct prefabricated components in the production of buildings. There is also a growing awareness by architects and builders of the environmental impact caused by the production, operation, and disposal of buildings. Since the industrial revolution, building materials have tended towards high-energy solutions, as materials of renewable origin are inherently difficult to manufacture to the tight tolerances demanded from modern design. Additionally, they are perceived as more susceptible to fire and rot than many synthetic materials. Yet, impending energy shortages as well as environmental concerns now force us to reconsider if there are ways to use renewable materials without compromising design. One such material worthy of reconsideration is straw; which has been used for thousands of years in architecture. Straw refers to the dried stems of grain bearing grasses, which are often burned or tilled back into the soil after the grain has been harvested. This paper will survey the current global production of straw and the environmental impact of straw use in construction. Further, it will identify future opportunities for the use of straw in modern design. Included is a design for a straw insulation system for commercial architecture. The system is comprised primarily of straw with a bio-based shell. This insulation system is designed for disassembly from the other building systems so that these organic materials can return to their natural cycles at the end of the use phase. A sample design is given to demonstrate its use in construction, and prototypes are built to test the feasibility of this design. Computer simulations are performed to demonstrate hygro-thermal response of this design to the climates of Boston, Massachusetts; Minneapolis, Minnesota; and Los Angeles, California. Preliminary thermal testing of the prototypes qualitatively indicates their effectiveness. The analysis is then expanded to a discussion of the link between global waste generation, resource consumption, and life spans of building systems. Finally, a simple method of classifying natural resources is presented which may help educate future generations to better understand the full ramifications of design and development, and a life cycle analysis of the designed component is performed using this new classification scheme. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2003.; Includes bibliographical references (p. 143-158).

Metered energy consumption and analysis of energy conservation techniques in desktop PCs and workstations

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Metered energy consumption and analysis of energy conservation techniques in desktop PCs and workstations Bosko, Kristie L. (Kristie Lee) This thesis investigates potential energy savings due to the application of power managed PCS, monitors, and workstations. The basis of this effort includes electric metering of such equipment at six preliminary and one primary location, a large business office in Boston, Massachusetts. Metering there occurred over an 8 week period, using an in-line metering device, and at a resolution of one minute intervals. The results of this study show that many problems exist in the field today which prevent any energy savings from being realized. These include both software and hardware incompatibilities. It was found that either the equipment was not enabled from the beginning; that various problems caused inadvertent disabling of the energy saving features, or that lack of knowledge about specific power management techniques caused the user to intentionally disable the features. Since this work began, the EPA's Energy Star Computers and Monitors Program updated their requirements such that energy saving features are now enabled when they are shipped from the manufacturer. All computers tested in this investigation were installed before the application of this condition, which was October 1, 1995. However, many problems exist other than those remedied by this requirement, including: computers which disengage from the network environment upon entering the lowest power management levels, various software incompatibilities, problematic methods of achieving power reduction, and little to no training of users or even prior negative experiences with power managed equipment There is a need for manufacturers to develop suitable or standard methods of achieving power management In addition, computer procurement employees or users must be taught about power management methods, and must have an opportunity to voice questions or concerns to manufacturers regarding power managed equipment. More research needs to be focused on network incompatibilities. Specifically, many computers are disconnected from their network upon engaging the lowest power level. This is due to either unacceptable power management methods or "stand-alone" power manageable computers which are placed on a network. Users purchasing computers intended for network use should be informed about whether the energy saving features are compatible with their type of network. This thesis is divided into two parts, the first for PCs and the second for workstations. The primary metering site for workstations was the Massachusetts Institute of Technology, which contains both Energy Star compliant and non-compliant machines. Opportunities for energy conservation in workstations are compared and contrasted to those of desktop PCs and monitors. In addition, current and future trends in workstation manufacturing and their impacts on energy conservation are explored. Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1996.; Includes bibliographical references (p. 99-100).

An interactive performance-based expert system for daylighting in architectural design

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An interactive performance-based expert system for daylighting in architectural design Gagne, Jaime M. L. (Jaime Michelle Lee) Design practitioners are increasingly using digital tools during the design process; however, building performance simulation continues to be more commonly utilized for analysis rather than as a design aid. Additionally, while simulation tools provide the user with valuable information, they do not necessarily guide the designer towards changes which may improve performance. For designing with daylighting, it is essential that the designer consider performance during the early design stage, as this is the stage when the most critical design decisions are made, such as the overall building geometry and faqade elements. This thesis proposes an interactive, goal-based expert system for daylighting design, intended for use during the early design phase. The system gives the user the ability to input an initial model and a set of daylighting performance goals. Performance areas considered are illuminance and glare risk from daylighting. The system acts as a "virtual daylighting consultant," guiding the user towards improved performance while maintaining the integrity of the original design and of the design process itself. This thesis consists of three major parts: development of the expert system, implementation of the system including a user interface, and performance assessment. The two major components of the expert system are a daylighting-specific database, which contains information about the effects of a variety of design conditions on resultant daylighting performance, and a fuzzy rule-based decision-making logic, which is used to determine those design changes most likely to improve performance for a given design. The expert system has been implemented within Google SketchUp along with a user interface which allows a designer to fully participate in the design process. Performance assessment is done in two ways: first by comparing the effectiveness of the system to a genetic algorithm, a known optimization method, and second by evaluating the success of the user interactivity of the tool, its use within the design process, and its potential to improve the daylighting performance of early stage designs. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2011.; Cataloged from PDF version of thesis.; Includes bibliographical references (p. 223-233).

Church housing : a symbol of hospitality

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Church housing : a symbol of hospitality Kwack, Elizabeth S. (Elizabeth Sey-Kyung) This project is located in Bloomfield, NJ. Less than fifteen miles from New York City, the Township of Bloomfield was first settled by the Dutch in 1691 and later by the English in 1719. In 1812, the State of New Jersey finally incorporated Bloomfield as a township. Until then, it had been a parish of the city of Newark. The Township took its name from the Bloomfield Presbyterian Church. This church was named for General Joseph Bloomfield, the fourth Governor of New Jersey and the first Governor to be born in New Jersey Bloomfield prides itself on its rich historical background. In 1830, a town resident David Oakes established a woolen mill. This mill prospered and provided employment for hundreds of immigrants and among its various materials, uniforms for the Union Army in the Civil War. In addition, the Township housed many military leaders including General George Washington during the American Revolution. Moreover, the community's Green functioned as a military training ground during the war. Today, it remains among the most attractive features of Bloomfield. The Township Green and its surrounding buildings, including the Oakes' mansion, which is now used as a performing arts center, have been recognized as a historic district. In 1945, the Bethany United Presbyterian Church purchased a tract of property from the Township of Bloomfield. Like Bloomfield, this church has a meaningful history. Though the construction of the church building itself began in 1945, the church as a congregation became established years earlier. Its original meeting place was a local storefront just up the street of the now existing church. In 1947, the Bethany congregation marched down the street to its present location. It was a very ceremonial event that marked years of planning, prayer, hard work, and the faith of church leaders and members alike. In expressing the church's interest in obtaining the land, Reverend William H. Neebe, on behalf of Bethany's Board of Trustees wrote to the Bloomfield Town Council, "We believe that as a church we are rendering a public service to the community Our only reason for existence is for service to the town and community... .Anything that aids the church enhances the opportunity that the church has to serve the community." Thesis (S.B. in Art and Design)--Massachusetts Institute of Technology, Dept. of Architecture, 2002.; "June 2002." Unpaged. Cataloged from PDF version of thesis.

Preservation of early wrought iron trusses : the 1848 roof of the Cochituate gatehouse

2022-01-13T07:54:12Z

Preservation of early wrought iron trusses : the 1848 roof of the Cochituate gatehouse Ferriss, Lori (Lori E.) This thesis investigates the historic significance, structural condition, and preservation challenges of the wrought iron roof trusses of the Cochituate aqueduct's inlet gatehouse as the possible earliest surviving example of their type in the United States. Through an examination of the existing structure and archival documentation of the structure's history from archived documents, this project establishes the necessity for the structure's preservation and offers solutions for its future restoration. Thesis (S.B. in Art and Design)--Massachusetts Institute of Technology, Dept. of Architecture, 2009.; Cataloged from PDF version of thesis.; Includes bibliographical references (p. 51-52).

A global typology of cities : classification tree analysis of urban resource consumption

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A global typology of cities : classification tree analysis of urban resource consumption Saldivar-Sali, Artessa Niccola D., 1980- A study was carried out to develop a typology of urban metabolic (or resource consumption) profiles for 155 globally representative cities. Classification tree analysis was used to develop a model for determining how certain predictor (or independent) variables are related to levels of resource consumption. These predictor variables are: climate, city GDP, population, and population density. Classification trees and their corresponding decision rules were produced for the following major categories of material and energy resources: Total Energy, Electricity, Fossil fuels, Industrial Minerals & Ores, Construction Minerals, Biomass, Water, and Total Domestic Material Consumption. A tree was also generated for carbon dioxide emissions. Data at the city level was insufficient to include municipal solid waste generation in the analysis. Beyond just providing insight into the effects of the predictor variables on the consumption of different types of resources, the classification trees can also be used to predict consumption levels for cities that were not used in the model training data set. Urban metabolic profiles were also developed for each of the 155 cities, resulting in 15 metabolic types containing cities with identical or almost identical levels of consumption for all of the 8 resources and identical levels of carbon dioxide emissions. The important drivers of the differences in profile for each type include the dominant industries in the cities, as well as the presence of abundant natural resources in the countries in which the cities are the main economic centers. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2010.; Cataloged from PDF version of thesis.; Includes bibliographical references (p. 101-103).

Improving the Fanger model's thermal comfort predictions for naturally ventilated spaces

2022-01-13T07:54:12Z

Improving the Fanger model's thermal comfort predictions for naturally ventilated spaces Truong, Phan Hue The Fanger model is the official thermal comfort model in U.S. and international standards and is based on the heat balance of the human body with the environment. This investigation focuses on re-specifying the parameters in Fanger's model, the majority of which are empirically-derived coefficients, to improve its thermal comfort predictions for naturally ventilated spaces. A sensitivity analysis revealed that the comfort temperature prediction is by far most sensitive to the comfort value of mean skin temperature. Furthermore, the sensitivity analysis also indicated that for the Fanger model to produce better comfort temperature predictions for naturally ventilated buildings, the comfort mean skin temperature needs to be correlated to an outdoor climate variable, thereby accounting for the psychological adaptations of occupants of naturally ventilated buildings that were largely ignored in the original climate chamber derivation of this parameter. A modified comfort mean skin temperature, that is a function of both metabolic rate and outdoor effective temperature and is applicable to naturally ventilated environments only, produces comfort temperature predictions that agree well with field study data. The thermal sensation transfer coefficient was also updated based on a weighted multiple linear regression of field study data. The results suggest that a Fanger model with a modified comfort mean skin temperature and modified thermal sensation transfer coefficient can significantly improve the thermal comfort predictions for naturally ventilated spaces. However, experiments need to be conducted to determine the true functional forms of both parameters. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2010.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (p. 58-60).

Predictive pre-cooling control for low lift radiant cooling using building thermal mass

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Predictive pre-cooling control for low lift radiant cooling using building thermal mass Gayeski, Nicholas (Nicholas Thomas) Low lift cooling systems (LLCS) hold the potential for significant energy savings relative to conventional cooling systems. An LLCS is a cooling system which leverages existing HVAC technologies to provide low energy cooling by operating a chiller at low pressure ratios more of the time. An LLCS combines variable capacity chillers, hydronic distribution, radiant cooling, thermal energy storage and predictive control to achieve lower condensing temperatures, higher evaporating temperatures, and reductions in instantaneous cooling loads by spreading the daily cooling load over time. The LLCS studied in this research is composed of a variable speed chiller and a concrete-core radiant floor, which acts as thermal energy storage. The operation of the chiller is optimized to minimize daily energy consumption while meeting thermal comfort requirements. This is achieved through predictive pre-cooling of the thermally massive concrete floor. The predictive pre-cooling control optimization uses measured data from a test chamber, forecasts of controlled climate conditions and internal loads, empirical models of chiller performance, and data-driven models of the temperature response of the zone being controlled. These data and models are used to determine a near-optimal operational strategy for the chiller over a 24-hour horizon. At each hour, this optimization is updated with measured data from the previous hour and new forecasts for the next 24 hours. The novel contributions of this research include the following: experimental validation of the sensible cooling energy savings of the LLCS relative to a high efficiency split system air conditioner - savings measured in a full size test chamber were 25 percent for a typical summer week in Atlanta subject to standard efficiency internal loads; development of a methodology for incorporating real building thermal mass, chiller performance models, and room temperature response models into a predictive pre-cooling control optimization for LLCS; and detailed experimental data on the performance of a rolling-piston compressor chiller to support this and future research. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2010.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Cataloged from student-submitted PDF version of thesis.; Includes bibliographical references (p. 143-159).

Heat pump simulation model and optimal variable-speed control for a wide range of cooling conditions

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Heat pump simulation model and optimal variable-speed control for a wide range of cooling conditions Zakula, Tea The steady-state air-to-air heat pump model presented in this thesis was developed from the first principles. The main objective was to develop a heat pump model that can be used as a part of larger simulation models, and that will make a connection between simple models that do not describe equipment behavior accurately enough and complicated models that are computationally very expensive. The model consists of the evaporator, compressor and condenser sub-model, each modeling the steady-state behavior of a particular component. To confirm the model accuracy, simulation results are compared with the experimental data from the Mitsubishi "Mr. Slim"® heat pump. The reported COP prediction errors are up to 20% under-prediction when the evaporating temperature is more than 2 K under-predicted, and 10% when the evaporating temperatures are more accurately predicted (less then 2K underpredicted). The model is strongly sensitive on the evaporator temperature prediction errors, since they influence the compressor inlet density. A grid search optimization algorithm is used to find the heat pump optimal performance map. The map defines the optimal evaporator fan speed, condenser fan speed and compressor speed needed to achieve the lowest total power consumption for the given cooling rate, ambient and zone temperature. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2010.; "June 2010."; Includes bibliographical references (p. 127-129).

Regionalism and the design of low-rise building envelope systems

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Regionalism and the design of low-rise building envelope systems Tapia, Jason W. (Jason Wilfredo) This investigation proposes the use of a three-pronged approach to evaluating building envelopes for low-rise affordable housing in urban contexts: construction cost estimating, building performance modeling, and cradle to grave life cycle assessment. Two climate regions were investigated: hot-humid and hot-dry, in two large urban cities: Phoenix and Miami. The envelope systems compared were conventional for the practice area versus best practice and high r-value systems. The results demonstrate that the application of the three-pronged method yields data architects can use to improve energy performance, reduce costs and limit negative environmental impacts. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2010.; "June 2010."; Includes bibliographical references (p. 78-86).

Complete drawing prototypes for urban complete streets

2022-01-13T07:54:12Z

Complete drawing prototypes for urban complete streets Winder, James Ira A study was performed to determine how drawings for streets may be tailored to a broad range of viewers and agendas, yet still be viewed as a credible design tool for architects. With a growing number of cities designing their own guidelines according to the Complete Streets movements, it's necessary to develop a graphic style that not only appeals to the typical engineering aspect of streets, but is also robust enough to include details for various design components and spatial qualities not before considered in street design. New drawings and information graphics were invented to better describe multi-modal streets, spatial qualities, and a fully conceived taxonomy of urban street types. It was discovered that three drawing types are especially useful for conveying this type of information: Perspective- Sections, Overhead Views, and Transects. Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Architecture, 2010.

Unique airflow visualization techniques for the design and validation of above-plenum data center CFD models

2022-01-13T07:54:12Z

Unique airflow visualization techniques for the design and validation of above-plenum data center CFD models Lloyd, Michael David, S.M. Massachusetts Institute of Technology One cause for the substantial amount of energy used for data center cooling is poor airflow effects such as hot-aisle to cold-aisle air recirculation. To correct these and to investigate innovative designs that will notably increase efficiency requires a robust, well-verified computational fluid dynamics (CFD) model. Most above-plenum data center CFD models are only validated using temperature data. Although a temperature-only validation method can be useful, it does not confirm that the airflow patterns predicted by the CFD model are accurate. Since the airflow patterns above a raised-floor plenum should be confidently understood before they can be optimized, it is necessary to adopt a validation method that offers more than just a comparison of temperature data. This thesis summarizes the unique validation process of a CFD model for a small data center test cell located in Cambridge, Massachusetts. The validation method features point velocity and temperature measurements and the use of small neutrally-buoyant bubbles to visualize the airflow patterns above a raised-floor plenum. The data center test cell was designed to emulate a standard hot-aisle and cold-aisle airflow configuration. The airflow visualization revealed that each perforated tile had a substantial nonuniform air velocity distribution leading to an unexpected three-dimensional flow pattern above the racks. When this surprising reality was properly accounted for in the CFD boundary conditions, good agreement was found with the observed airflow patterns. It is the purpose of this thesis to show the difficulties and value of utilizing more robust validation techniques for data center CFD models. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2010.; Includes bibliographical references (p. 119-121).

The 4-dimensional masonry construction

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The 4-dimensional masonry construction Davis, Lara K. (Lara Katherine) This design-research thesis - The 4-Dimensional Masonry Construction - presents innovation in the design and construction of thin-shell tile vaulted structures. The core research contributions of this thesis are: #1 Testing limit states of unit hinging + displacement in single-layer tile vaults. #2 Introducing modified masonry units to achieve directional surfaces with high degrees of double-curvature and porosity. The 4-Dimensional Masonry Construction operates as a heuristic device to conceptualize, visualize and represent the way in which a masonry unit hinges in space within a complex, doubly-curved structural surface. By modifying masonry units, the resulting system of aggregation can produce asymmetrical and disaggregating tile coursing geometries - predictable yet geometrically incomprehensible systems. By establishing reciprocity between the modified unit/ system relation and the method of vault assembly, new forms in structural masonry are possible. Such structural forms are a product of these unique unit/ system geometries, the constraint of structural geometries (catenary systems and double curvature for lateral stiffness), the techniques of graphical analysis to define such a structure spatially, and the logic of sequencing to maintain the units' systematic relation, to constrain units inherently given to push the limits of constructibility. Thesis (M. Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 2010.; Cataloged from PDF version of thesis.; Includes bibliographical references (p. 132).

An urban weather generator coupling a building simulation program with an urban canopy model

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An urban weather generator coupling a building simulation program with an urban canopy model Bueno Unzeta, Bruno The increase in air temperature observed in urban environments compared to the undeveloped rural surroundings, known as the Urban Heat Island (UHI) effect, is being intensely studied, due to its adverse environmental and economic impacts. Some of the causes of the UHI effect are related to the interactions between buildings and the urban environment. This thesis presents a methodology intended to integrate building energy and urban climate studies for the first time. It is based on the premise that at the same time buildings are affected by their urban environment, the urban climate is affected by the energy performance of buildings. To predict this reciprocal interaction, the developed methodology couples a detailed building simulation program, EnergyPlus, with a physically based urban canopy model, the Town Energy Balance (TEB). Both modeling tools are leading their respective fields of study. The Urban Weather Generator (UWG) methodology presented in this thesis is a transformation of meteorological information from a weather station located in an open area to a particular urban location. The UWG methodology fulfils two important needs. First, it is able to simulate the energy performance of buildings taking into account site-specific urban weather conditions. Second, it proposes a building parameterization for urban canopy models that takes advantage of the modelling experience of a state-of-the-art building simulation program. This thesis also presents the application of the UWG methodology to a new urban area, Masdar (Abu Dhabi). The UHI effect produced in this hot and arid climate by an urban canyon configuration and its impact on the energy performance of buildings are analyzed. Thesis (S.M. in Building Technology)--Massachusetts Institute of Technology, Dept. of Architecture, 2010.; Cataloged from PDF version of thesis.; Includes bibliographical references (p. 125-128).

Managing stormwater in Watertown, MA : overcoming obstacles to change

2022-01-13T07:54:44Z

Managing stormwater in Watertown, MA : overcoming obstacles to change Chai, Shutsu K. (Shutsu Kindness) As effective imperviousness increases with urbanization, the impacts of stormwater runoff on local water systems and aquatic life are more and more deleterious. Stormwater runoff carries pollutants into nearby water bodies, alters stream banks, reduces stream base flows and bypasses infiltration processes that both clean and recharge groundwater. While these consequences are still invisible to the average citizen, human life is wholly dependent on adequate quantity and quality of water resources, which polluted stormwater runoff threatens. This link has motivated more widespread attention to and effort in stormwater management, yielding new technologies, initiatives and solutions. As this new paradigm for stormwater management grows better established and more broadly accepted, the struggles to minimize the impact of runoff have shifted from the technology to implementation. A deeper understanding of the challenges and barriers to the adoption of new best management practices will allow us to better target efforts to overcome those obstacles. Conducting a case study of Watertown, MA, I interviewed local officials, planners and activists. Through these conversations, I identified four primary barriers: funding shortages, disagreement over implementation mechanisms, knowledge limitations and site constraints. Despite these limitations, educational programs, codified local regulations coupled with design guidelines and a flexible local funding source can help localities surmount those hurdles. Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2009.; Includes bibliographical references (p. 65-68).

Thrust Network Analysis : exploring three-dimensional equilibrium

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Thrust Network Analysis : exploring three-dimensional equilibrium Block, Philippe (Philippe Camille Vincent) This dissertation presents Thrust Network Analysis, a new methodology for generating compression-only vaulted surfaces and networks. The method finds possible funicular solutions under gravitational loading within a defined envelope. Using projective geometry, duality theory and linear optimization, it provides a graphical and intuitive method, adopting the same advantages of techniques such as graphic statics, but offering a viable extension to fully three-dimensional problems. The proposed method is applicable for the analysis of vaulted historical structures, specifically in unreinforced masonry, as well as the design of new vaulted structures. This dissertation introduces the method and shows examples of applications in both fields. Thrust Network Analysis, masonry, historic structures, compression-only structures, limit analysis, equilibrium analysis, funicular design, form-finding, structural optimization, Gothic vaults, reciprocal diagrams. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2009.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Includes bibliographical references (p. 145-153).

Seismic assessment strategies for masonry structures

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Seismic assessment strategies for masonry structures DeJong, Matthew J. (Matthew Justin) Masonry structures are vulnerable to earthquakes, but their seismic assessment remains a challenge. This dissertation develops and improves several strategies to better understand the behavior of masonry structures under seismic loading, and to determine their safety. The primary focus is on historic arched or vaulted structures, but more modern unreinforced masonry structures are also considered. Assessment strategies which employ simplified quasi-static loading to simulate seismic effects are initially addressed. New analysis methods which focus on stability or strength are presented, and the merits of these strategies are clarified. First, a new parametric graphical equilibrium method is developed which allows real-time analysis and illuminates the complex stability of vaulted masonry structures. Second, a finite element strategy for predicting brittle fracture of masonry structures is extended to incorporate non-proportional loading and shell elements. These extensions enable prediction of damage and collapse mechanisms in general, but are specifically used to predict the response of a full-scale masonry structure to quasi-static cyclic loading. Subsequently, assessment methods based on the dynamic response of masonry structures under earthquake loading are presented. First, rigid body dynamics and an experimental testing program are used to characterize the rocking response of the masonry arch for the first time.; (cont.) An assessment criterion is developed which successfully predicts experimentally observed arch collapse under a variety of earthquake time histories. Second, the behavior of rocking structures is addressed in general, and clearly distinguished from typical dynamic oscillators. The rocking response is time dependent, evoking the development of a statistical method for predicting collapse. Finally, the ability of discrete element methods to predict the dynamics of masonry structures is evaluated through comparison with analytical and experimental results, and a rational method for assigning modeling parameters is proposed. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2009.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Includes bibliographical references (p. 181-189).

Fault detection methods for vapor-compression air conditioners using electrical measurements

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Fault detection methods for vapor-compression air conditioners using electrical measurements Laughman, Christopher Reed. (cont.) This method was experimentally tested and validated on a commercially available air handler and duct system. In the second class of faults studied, liquid refrigerant, rather than vapor, enters the cylinder of a reciprocating compressor during operation. Since the higher cylinder pressures that result can cause substantial damage and are difficult to measure directly, a method for detecting this fault is proposed that only uses observations of the compressor voltage and current. The performance of this fault detection method was also experimentally validated with electrical and mechanical measurements on a semi-hermetic compressor. The final diagnostic method detects refrigerant leakage in a residential air conditioning system by identifying changes in the system's cycling behavior. This method also uses measurements of the compressor's electrical power, as well as a small set of temperature measurements, to determine the presence of the fault. This fault detection method was developed and tested on an occupied residence.; This thesis proposes novel methods that use measurements of electrical terminal variables to identify common mechanical faults in vapor-compression air-conditioners. The importance of air-conditioning in many applications and the current cost of energy both provide powerful incentives for developing fault detection methods, as faults can have a significant impact on the system's functionality and efficiency. While many extant fault detection and diagnostic (FDD) methods depend upon arrays of mechanical sensors, concerns about sensor reliability and the overall complexity of these methods motivated this research into electrically-based FDD methods, which typically incorporate smaller numbers of more reliable sensors. These electrically-based methods use models of the electromechanical energy conversion process to correlate observed changes in the electrical variables to changes caused by faults in the mechanical load. Such an approach allows both electrical and mechanical faults to be identified via the same sensor apparatus, and makes it possible to identify faults that manifest themselves on a wide range of timescales.FDD methods for three different classes of common faults are studied in this research. The first diagnostic method identifies blockage or leakage in a duct via electrical measurements made at the fan motor terminals. The estimates of the motor's speed and torque developed at the operating point are used in tandem with a fan curve to directly estimate the airflow through a duct system without any additional mechanical measurements. Includes bibliographical references (p. 409-424).; Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2008.

Structural analysis and assessment of Guastavino vaulting

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Structural analysis and assessment of Guastavino vaulting Reese, Megan L This thesis studies the behavior and pathologies of the masonry tile structures built by the R. Guastavino Company in order to provide recommendations on their analysis and assessment. Structural analyses of two specific geometries - domes and barrel vaults - are carried out with equilibrium and elastic methods to determine how well each assesses the safety of Guastavino shells. Results show that stresses are relatively low in these structures, so they are unlikely to fail due to inadequate material capacity. The safety, then, is dependent on the stability of the structure rather than its material strength. Analysis of a Guastavino structure should demonstrate its stability, and graphical equilibrium analysis is well-suited to this task. Case studies of three Guastavino projects - the Grace Universalist Church, the Saint Louis Art Museum, and the Army War College - provide examples of pathologies specific to masonry tile structures and demonstrate how they were successfully or unsuccessfully analyzed and rehabilitated in the past. Guastavino shells exhibit behavior similar to other masonry structures, but have an additional characteristic that sets them apart: soffit tiles can debond and fall as a result of cracking or water damage. Falling tiles pose a serious mortal danger but do not necessarily threaten a structure's safety. Nonetheless, they elicit dramatic structural repairs and retrofits. The case studies present an opportunity to critically evaluate structural interventions with an understanding of masonry tile vault behavior. By bringing both sensitive and unsuccessful rehabilitations to light, hopefully Guastavino shells will be protected from unnecessary retrofits in the future. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2008.; Includes bibliographical references (p. 122-125).

RISK COMPLEX : preparing the body for new hardware

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RISK COMPLEX : preparing the body for new hardware Voiland, Luke (Luke A.) Today's citizen navigates a vast society engaged in the explicit of wealth and implicit creation of risks. Each transaction inhere es both wealth and risk within the system. In 1986 Utrich Beck explanation for this emerging post modern condition. His work, Risk Society: Towards a New Modernity, sketches the outlines of a society the management and reduction of risk. Beck recognizes that a reach a point where efforts to increase wealth will be supersede to avoid risk. The organization of society will shift from the pro distribution of goods and services, to the redistribution and r risk. Through play activities the RISK COMPLEX will prepare cit risk society. The RISK COMPLEX seeks to provide a space that empowers the individual within the complicated web of risk connections. Visitor to the RISK COMPLEX learn about methods and technologies that allow their individual risk. In the same way a child uses play to simulate ... empower individuals within the Risk society. Sited on Coney island the RISK COMPLEX taps into historical plays cape that include the beach and boardwalk. The architecture links to the existing amusement infrastructure but seeks to carve out a seperate matrix of simulated risks that individuals can engage. Thesis (M. Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, June 2008.; Includes bibliographical references (p. 92-94).

Modeling the resource consumption of Housing in New Orleans using System Dynamics

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Modeling the resource consumption of Housing in New Orleans using System Dynamics Quinn, David James, Ph. D. Massachusetts Institute of Technology This work uses Systems Dynamics as a methodology to analyze the resource requirements of New Orleans as it recovers from Hurricane Katrina. It examines the behavior of the city as a system of stocks, flows and time delays at a macro-level. The models used to simulate this behavior are compared to historic data. The construction materials, energy and labor required to construct several different types of housing systems are examined and these data are combined with the macro-scale analysis of the city. Several alternative scenarios are proposed based on the interactions of feedback loops identified. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2008.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Includes bibliographical references (p. 130-136).

Revealing the potential of Compressed Earth Blocks : a visual narration

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Revealing the potential of Compressed Earth Blocks : a visual narration Rabie, Omar Compressed Earth Blocks (CEB) is a developed earth technology, in which unbaked brick is produced by compressing raw soil using manual, hydraulic, or mechanical compressing machines. Revealing the potential of an affordable sustainable material like CEB may help tackle today's fundamental challenges, social equity and environmental sustainability. For one year in India, I learned and practiced the basics of this technology in Auroville Earth Institute, and then conducted a group of design and construction experimentations for a natural resort project. Through these experimentations, I tried to reveal CEBs' capabilities through design innovation. The thesis captures my new understandings of the design competence of the material in relation to the design process, through narrating the story of this experience using images and a dialogue between the designer, mason, sponsor and the blocks themselves. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2008.; Includes bibliographical references (leaves 63-64).

Valuable bridges : cable-stayed bridges and value engineering in American civil engineering culture, 1969-1979

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Valuable bridges : cable-stayed bridges and value engineering in American civil engineering culture, 1969-1979 Samuels, Fallon M. (Fallon Michele) A history and theory of cable-stayed bridges in the context of a cultural discourse on civil construction projects' value, this thesis studies the significance of cable-stayed bridge designs to 'value engineering' objectives for major highway bridge projects of the 1970s. This study of preliminary designs and feasibility studies for highway bridges presents the alternate bridge designs versus alternative bridge typologies selected during this period as one instance of American civil engineering culture adapting to major bridge projects the economically measured but industrial approach to choosing, reconfiguring and eliminating construction systems of value engineering. Only as analytical mechanisms of bridge construction that figure as economically competitive in prevailing market conditions do the high-capital and technologically innovative bridge designs of the Luling Bridge (LA, 1978) and the Pasco-Kennewick Bridge (WA, 1977) develop into physical constructions built almost exclusively with federal highway funds. This shift in cable-stayed bridge designs' fate from abandoned projects in the 1960s is discussed as the reflection of structural engineers' engaging in the post-capitalist practices of analytical and then physical systems building, decision analysis, speculation as well as the interdisciplinary cultures from which these concepts stem. Critical studies of preliminary designs and construction industry data circa 1970 reveal cable-stayed bridge type selections to be at once the linchpin to politicization of VE in American highway bridge building by 1979 and the Achilles heel of an American civil engineering culture that sought a renaissance in bridge engineering not a redefinition of its principles through a new method of planning for alternate futures. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2007.; Page 109 blank.; Includes bibliographical references (p. 99-108).

Transition dynamics between the multiple steady states in natural ventilation systems : from theories to applications in optimal controls

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Transition dynamics between the multiple steady states in natural ventilation systems : from theories to applications in optimal controls Yuan, Jinchao In this study, we investigated the multiple steady state behavior, an important observation in numerical and experimental studies in natural ventilation systems. The-oretical models are developed and their applications in numerical simulations and ventilation controls are presented. In a system with multiple steady states, how the system reaches different steady states is determined by the initial values of the systems and the dynamical system characteristics of the system. Mathematical models are developed to model the dynamical system behavior of a series of ventilation systems, ranging from simple single-zone systems to complex systems with thermal mass. More importantly, we found that the system can transform from one steady state to another under sufficient perturbations (disturbances) when multiple steady states exist. A successful transition is determined by both the magnitudes and durations of the perturbations. The transition dynamics are found to be important in theoretical, computational, and control applications. For example, the actual stability of a mathematically (or locally) stable steady state is highly correlated to the minimum perturbation requirements for a state transition. If two indicative parameters-the minimum perturbation time and the minimum perturbation magnitude-are small for the system to transit from one steady state to another, a mathematically stable steady state can be unstable in actual conditions, where stochastic disturbances exist as "strong perturbations". Further, building thermal mass is also found to have significant impacts on the state transitions between the multiple steady states. With thermal mass, the state transition becomes more difficult to occur. The state transition dynamics can also be applied to numerical simulations.; (cont.) We have developed a convenient dynamical simulation method to identify the possible steady states in buildings with complex geometries and test the stabilities of the obtained steady states. The method can determine nearly all the possible steady state the system may reach in a feasible range using different search methods; whether the steady states obtained are stable in an actual environment can also be determined by a disturbance test based on the transition dynamics between the multiple steady states.Further, the state transition dynamics can be strategically applied in hybrid ventilation controls. In the past, designers and engineers have viewed the multiple steady states as negative aspect of ventilation design and have been trying to avoid the multiple steady states as much as possible. In this study, we have developed positive applications of multiple steady states based on a dynamic state transition in real-time to enhance the ventilation efficiency of a hybrid ventilation system and to reduce the energy usage in buildings. A coupled multi-zone airflow and thermal program for transient entire building simulations is also developed in parallel with the study. With the understanding on the multiple steady state issues, the developed program has overcome a few non-trivial numerical problems reported in other similar simulation programs and has shown good numerical performance in coupled airflow and thermal analysis. The program is also used as a tool for identifying the multiple steady states in buildings with complex geometries and for testing the actual stabilities of the obtained steady states in real conditions. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2007.; Includes bibliographical references (p. 269-274).

The design of effective policies for the promotion of sustainable construction materials

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The design of effective policies for the promotion of sustainable construction materials Kua, Harn Wei, 1971- This research explores the associated effects of policy tools employed to promote sustainable building materials. By comparing the original motivations and intended effects of these policies and their actual outcome, and subsequently understanding the reasons behind any disparities between them, we suggest ways by which future policy planning can be improved. This research is based on seven detailed case studies. They cover the applications of virgin material taxes in Denmark and Sweden, forest management and biodiversity legislations in United States' Northwest and its coupling economic adjustment initiative, legislations/public outreach/demonstration projects on the use of substitute fuels for cement manufacturing in United States and the United Kingdom, and economic incentives to promote afforestation/reforestation in Chile. Each of these cases is attended by negative, unanticipated outcomes. By analyzing these outcomes, we observe that a negative and unanticipated policy outcome occurs when a sustainability indicator/issue is either completely ignored by policymakers, or the policymakers fail to identify intrinsic but inconspicuous links between seemingly disparate indicators.; (cont.) These unexpected outcomes can be reduced, or avoided, if policymakers conceptualize policies more broadly, for which purpose we propose the concept of integrated policymaking. This concept promotes the idea of co-addressing, or even co-optimizing, a wide range of eleven to sixteen sustainability indicators covering all the three domains of sustainability - economy, environment and employment. Furthermore, in doing so, policymakers must promote interactions among the different levels of governmental agencies (i.e. horizontal and vertical integration) and between the governmental and non-governmental stakeholder groups (i.e. time horizon integration and integration across stakeholder groups). We emphasize the significance of five different but interrelated types of feedback loops in supporting these different types and goals of integration. Finally, we applied this concept to the seven cases and proposed a series of innovative integrated policy strategies to address the negative, unanticipated outcomes observed. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2006.; Includes bibliographical references.

Dynamic interrelationship between technology and architecture in tall buildings

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Dynamic interrelationship between technology and architecture in tall buildings Moon, Kyoung-Sun The interrelationship between the technology and architecture of tall buildings is investigated from the emergence of tall buildings in the late 19th century to the present. Through the historical research, a filtering concept is developed - original technology and remedial technology - through which one can clearly understand the interrelationship between the technological evolution and architectural esthetic and further stylistic transition of tall buildings. More desirable visions for the future can be constructed based on this concept. Contemporary design practice of tall buildings is reviewed, and design guidelines are provided for new design trends. Investigated in depth are the behavioral characteristics and design methodology for diagrid structures, which emerge as a new direction in the design of tall buildings with their powerful structural rationale and symbolic architectural expression. Moreover, new technologies for tall building structures and facades are developed for performance enhancement through design integration, and their architectural potentials are explored. Special emphasis is placed on the research on the structural dynamic motion control using double skin facades / distributed tuned mass dampers. Design integration among architecture-related disciplines is emphasized throughout the research process as a means to more effectively overcome or at least minimize contemporary technological limitations and to create architecture of higher quality.; (cont.) While each study makes its own contribution theoretically and in a particular design situation, from a wider viewpoint, the contribution of this thesis is to create more constructive relationships of architecture-related disciplines to produce better architecture through synergistic effects. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2005.; Page 230 blank.; Includes bibliographical references (p. 225-229).

Study of natural ventilation design by integrating the multi-zone model with CFD simulation

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Study of natural ventilation design by integrating the multi-zone model with CFD simulation Tan, Gang, 1974- Natural ventilation is widely applied in sustainable building design because of its energy saving, indoor air qualify and indoor thermal environment improvement. It is important for architects and engineers to accurately predict the performance of natural ventilation, especially in the building design stage. Unfortunately, there is not any good public tool available to predict the natural ventilation design. The integration of the multi-zone model and the computational fluid dynamics (CFD) simulation provides a way to assess the performance of natural ventilation in whole buildings, as well as the detailed thermal environmental information in some particular space. This work has coupled the multi-zone airflow model with the thermal model. A new program, called MultiVent, has been developed with a web-server that can provide online calculation for the public. The MultiVent program can simultaneously simulate the indoor air temperature and airflow rate with known indoor heat sources for buoyancy dominated, buoyancy-wind combined and wind dominated cases. To properly apply the MultiVent program to the natural ventilation design, two configurations in naturally ventilated buildings should be carefully studied: the atrium and large openings between the zones. A criterion has been set up for dividing the large opening and the connected atrium space into at least two sub-openings and sub-zones. The results of the MultiVent calculation can provide boundary conditions to the CFD simulation for some particular zone. In order to correctly simulate the particular space with CFD, the location and conditions at the integrating surface (boundary surface) have been studied. This work suggested that the simulation zone should include part of the connected atrium space when; (cont.) the occupied room is simulated with CFD. There are two options to integrate the MultiVent and CFD simulation through different boundary conditions: velocity (mass) integration and pressure integration. The case studies of this work showed that both of them can generate good CFD simulation results. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2005.; Includes bibliographical references (p. 150-154).

Development of two heliodon systems at MIT and recommendations for their use

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Development of two heliodon systems at MIT and recommendations for their use Osser, Roselin E. (Roselin Emily) Heliodons aid the building design process by allowing the simulation of different solar angles with respect to physical scale models. At MIT, two different variations of this kind of setup are being developed. The first one consists of a small, portable heliodon that is manually operated, and meant for use outdoors with the real sun and sky. The second is a larger indoor setup that consists of a computer-controlled moving table exposed to a stationary light source. A computer interface allows the designer to automatically take different sets of model photos from a camera positioned next to or inside a model, and view the images in useful ways. Both approaches are presented in this paper and their limitations, causes of inaccuracy and potentialities are discussed based on experimental verification and through Radiance simulations. The results of a usability study with student volunteers and a case study on an existing research space on the MIT campus are also presented as a means of illustrating the potential value of such devices for building design investigation and development. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2007.; Includes bibliographical references (p. 145-152).

Opportunities for building design and construction resulting from local resources

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Opportunities for building design and construction resulting from local resources Weathers, Thomas A. (Thomas Anthony) Current and future generations of architects must learn to operate effectively in an era of unprecedented resource constraints if they want to achieve their design intentions. This thesis addresses the architect's role in resource consumption. Specifically, it explores the potential for design and construction constrained to local resources. This research encompasses the following questions:What are the material resources local to MIT? What are the architectural and logistical limitations of using those resources in buildings? How might this research shape a building at MIT? By auditing local resources and industries, this thesis highlights unique opportunities for an architect to mobilize sustainable materials for MIT's growth. The subsequent design exercise transforms this knowledge into building strategies responsive to material and energy constraints. This new building serves to increase the density of MIT's east campus, developing underutilized lots on the edge of a future quad and rehabilitating a condemned structure. A framework of fixed and fluid components allows for sustainable adaptation, creating a flexible environment sought by emerging interdisciplinary groups. Thesis (M. Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 2007.; Includes bibliographical references (p. 48-51).

Methodology for the evaluation of natural ventilation in buildings using a reduced-scale air model

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Methodology for the evaluation of natural ventilation in buildings using a reduced-scale air model Walker, Christine E. (Christine Elaine) Commercial office buildings predominantly are designed to be ventilated and cooled using mechanical systems. In temperate climates, passive ventilation and cooling techniques can be utilized to reduce energy consumption while maintaining occupant comfort using natural ventilation. However, current modeling techniques have limitations and assumptions that reduce their effectiveness in predicting internal building performance. There are few tools to predict the thermal performance of and resulting airflow patterns in naturally ventilated office buildings accurately. This thesis presents three significant contributions for the evaluation of natural ventilation in buildings: * A methodology for assessing the performance of naturally ventilated buildings through a reduced-scale air model was developed based on dimensional analysis and similitude criteria. Buoyancy, wind, and combined ventilation strategies for a multi-zoned commercial office building with an open floor plan layout were evaluated using the reduced-scale model. * Guidelines were established for monitoring natural ventilated buildings as a means to evaluate their operation, based on field measurements of a prototype building were established. * A framework for evaluating current techniques for modeling airflow patterns in naturally ventilated buildings was developed, including guidelines for model development and analysis. Data from the reduced-scale model were compared to the data obtained from monitoring a prototype building and then used in creating numerical simulations.; (cont.) Certain building characteristics, such as atrium stack vents and railings, influenced the resulting simulation predictions and simple analytical model results. Lack of detailed temperature stratification and surface temperature data in the prototype building prohibited the exact comparison of the methodology for more complex design characteristics, such as thermal mass. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2006.; Includes bibliographical references (p. 167-171).

Catalan vaulting in advanced material : new approaches to contemporary compressive form

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Catalan vaulting in advanced material : new approaches to contemporary compressive form Ramage, Michael H. (Michael Hector) The translation of traditional building methods to modern construction techniques offers unexplored opportunities for material and form in architecture. Recent innovations in cellular ceramics married with traditional timbrel vaulting suggest a new approach to compressive form in structural masonry spans. Research into the history and construction of timbrel vaults and the material properties of cellular ceramic masonry shows that they are well-suited to one another. Building timbrel vaults with aerated autoclaved concrete (AAC) brings to architectural practice a new family of economically viable, expressive configurations of structural spans in masonry. The Catalan masonry technique, also referred to as timbrel or Guastavino vaulting, allows thin structural spans to be built without the use of supporting formwork. Once widely used in American construction, the technique is now little-known. This thesis documents the recent construction of two 11.3m (37') domes in England and structural research into building timbrel vaults with AAC tile. An artist's studio designed based on the information gained demonstrates the renewed feasibility of building expressive masonry structures. The techniques used to design and build structural masonry spans show that merging modern materials with traditional craft capitalizes on the significant strengths of each. These new buildings demonstrate the economic efficiency and formal viability of timbrel vaulting in contemporary architecture. Thesis (M. Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 2006.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Includes bibliographical references (p. 55-57).

A standard simulation testbed for the evaluation of control algorithms & strategies related to variable air volume HVAC systems

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A standard simulation testbed for the evaluation of control algorithms & strategies related to variable air volume HVAC systems DeSimone, Mark The parameters for a dynamic, computer simulation model were developed. The parameters characterize the physical and geometric properties of a building shell, the internal and external building loads, the buildings secondary systems, and the plant or primary energy source. The purpose of the model is to provide a standard testbed for the evaluation of control algorithms and strategies related to variable air volume HVAC systems. This work was conducted in collaboration with, and under subcontract to Loughborough University of Technology, Loughborough England. The prototype building is a four level commercial, multi-use building and activities in the building include classroom / educational space professorial and student offices, and office / administrative. The building contains three air-handling units; one unit and the volume it serves provides the basis for the testbed. The model volume is divided into thirty four zones, each with its own single duct, pressure independent V A V terminal box with hot water reheat. A perimeter heating system, composed of hot water convectors, radiators and baseboard heaters, augments the room comfort control system. Local loop control in the mechanical room and for all but one of the zones is micro-processor based pneumatic actuated. One prototype direct digital control terminal box system was in use for a classroom zone. DDC control systems and motor driven actuators were substituted in the testbed for the pneumatic equipment. Zoning in the volume was redistributed into six zones; the supply and return duct system was redesigned to accommodate the simplified zone configuration. A survey was conducted to determine the availability of sub-one-hour solar and collateral weather data. Historically, data in this frequency has been collected, but, not reported. A relatively new program called the Automated Surface Observing System (AS OS) and operated by the National Oceanic and Atmospheric Administration will eventually provide weather data at varying intervals down to one minute, depending on the type of information required. Daily and monthly summaries are available, however, resolution is reduced and averaged to one hour intervals. The SOLMET program, under the auspices of DOE, provides archived solar data at one hour intervals on CD Rom. Data is collected from twenty-six stations distributed around the United States. Collateral weather data is also provided with the solar data and for simulation purposes the SOLMET data provides the best resource.; Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1995.; Includes bibliographical references.

Equilibrium analysis of masonry domes

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Equilibrium analysis of masonry domes Lau, Wanda W This thesis developed a new method to analyze the structural behavior of masonry domes: the modified thrust line analysis. This graphical-based method offers several advantages to existing methods. It is the first to account for the ability of domes to achieve a range of internal forces, gaining potentially an infinite number of equilibrium solutions that could not be derived otherwise. This method can also analyze non-conventional axisymmetrical dome geometries that are difficult or impossible to analyze with existing methods. Abiding by limit state conditions and the principles of the lower bound theorem, the modified thrust line method was used to ascertain the theoretical minimum thrust of spherical and pointed domes, a parameter that was previously unsolved. Several methods to estimate minimum thrust to-weight ratio were provided. For spherical domes, this ratio may be estimated as -0.583[alpha] + 1.123; for pointed domes, the estimated ratio is 0.551[delta] -1.061[delta]/[alpha] -0.615[alpha] + 1.164, where [alpha] and [delta] are the embrace and truncating angles, respectively.; (cont.) From the results, salient relationships between minimum thrust and dome geometry were derived, including an inverse relationship between the minimum thrust and the thickness-to-radius ratio, angle of embrace, and, for pointed domes, the truncation angle of the crown for a constant angle of embrace. The capabilities of the modified thrust line method were demonstrated in two masonry dome case studies that existing methods could not successfully analyze. The potential of this method to predict the ultimate load capacity of masonry domes was also explored. The method overpredicted the capacity of two small-scale masonry domes loaded to failure by a concentrated applied load at the crown; however the small size of the domes compared to real-world domes suggested that scale effects may have influenced their behavior. Finally, interactive geometry programs of the modified thrust line method and other existing graphical analysis methods were created to disseminate these illustrative tools to understanding the structural behavior of masonry domes. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2006.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Includes bibliographical references (p. 121-123).

A system for optimizing interior daylight distribution using reflective Venetian blinds with independent blind angle control

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A system for optimizing interior daylight distribution using reflective Venetian blinds with independent blind angle control McGuire, Molly E An operational algorithm for blind angle control is developed to optimize the daylighting performance of a system of reflective Venetian blinds. Numerical modeling and experiment confirm that independent control of alternating blinds yields adequate visual comfort and daylight distribution to a distance of 10 m from the window under most clear sunny and overcast sky types. Under overcast sky conditions, all blinds are set to a uniform angle which optimizes light redirection to 10 m. For cases of direct solar incidence, alternating blinds are used for shading and light redirection and adjusted with changing solar position. For low solar angles, a set of blind angle configurations is developed utilizing blind-blind reflections to maximize light penetration. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2005.; Includes bibliographical references (p. 94-96).

Passive electromagnetic damping device for motion control of building structures

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Passive electromagnetic damping device for motion control of building structures Palomera-Arias, Rogelio, 1972- The research presented in this thesis develops a new device for the passive control of motion in building structures: an electromagnetic damper. The electromagnetic damper is a self-excited device that provides a reaction force to an applied motion. We chose a tubular permanent-magnet linear machine as this new structural damper, and we derive its mathematical model using quasi-static electromagnetic theory. Computer simulations and experimental characterization of a small-scale prototype electromagnetic damper validated the mathematical model of the device. The behavior of the electromagnetic damper approximates that of an ideal damper. We conducted a feasibility study for the application of electromagnetic dampers to full-scale buildings. We used two performance measures: the damping density and the damping cost of the device. Comparing the performance of the electromagnetic damper to that of viscous fluid dampers, the maximum damping density of electromagnetic dampers is, at best, equal to that of hydraulic dampers, but with a price at least five times higher. The permanent magnet's current technology and cost are the limiting factors for the electromagnetic damper.; (cont.) However, the electromagnetic damper provides flexibility not available previously to building designers as it can be used as a semi-active damper, as an actuator or as an energy regenerator without physical modifications to the device. Finally, we developed a design methodology for the electromagnetic damper to achieve a specified damping performance and introduced two techniques for the dynamic response analysis of buildings with electromagnetic dampers: One based on frequency domain approximations and one based on state-space models. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2005.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Includes bibliographical references (leaves 112-115).

Material flow analysis of concrete in the United States

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Material flow analysis of concrete in the United States Low, Man-Shi Concrete is the second most consumed material in the world after water. Due to the sheer mass of concrete consumed annually and its associated resource and environmental impacts, improving the materials management of concrete consumption is a critical problem in the United States. It is increasingly evident that the society lacks knowledge of the collective material composition of the urban environment-of how we produce, consume and dispose of concrete. This thesis argues that the lack of informational linkages is driving the individual approaches of the construction industry, policy makers, environmental agencies and waste management industry, which results in the current segregated and government-subsidized material management. In order to identify opportunities for more effective materials management, this thesis performs the first comprehensive Material Flow Analysis for concrete in the United States for the year of 1996 to identify opportunities for more effective materials management. The dominant concrete products and the end-use categories in the United States are identified. The associated water, energy and fuel consumption and emissions produced are also incorporated. Five lifecycle stages are covered: (i) extraction of raw materials, (ii) cement manufacturing, (iii) production, (iv) use and (v) waste management of concrete. Two untapped material management opportunities are identified: minimizing water consumption during the extraction stage and the off-site production stage.; (cont.) In addition, three key observations are made: (i) the energy efficiency of the cement industry in the United States is close to saturation, (ii) product choice and concrete design are dominant factors for a more responsible materials consumption approach, and (iii) demand-side management is recommended as a more optimal approach than recycling in dealing with the current construction trends in the United States. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2005.; MIT Rotch Library copy is in leaves.; Also issued in leaves.; Includes bibliographical references (p. 155-164).

Beyond blue and red arrows : optimizing natural ventilation in large buildings

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Beyond blue and red arrows : optimizing natural ventilation in large buildings Meguro, Wendy (Wendy Kei) Our growing understanding of technology and environment has expanded the complexities of producing large naturally ventilated buildings. While it may be argued that designing for natural ventilation is a straightforward, intuitive process, somewhere between the simple diagrams and signing off on the building, the designer must be able to verify that the design will be effective -- essentially that people will be comfortable, and that the system is robust. Today, professional experience is the only methodology to understand the broad considerations behind these new structures. Literature reviews and interviews with industry professional illustrate the lack of information available to the academic and practicing audiences describing the series of calculated decisions and challenges surrounding the design of large naturally ventilated buildings. Architecture professionals and students desiring to engage in these recent, innovative practices would therefore benefit from a resource describing the options available to evaluate a proposed design and optimize a completed building. The thesis examines the strategic decisions in evaluation and monitoring of three case study buildings (Morphosis' San Francisco Federal building, Fosters & Partners' Swiss Re building, and Behnisch & Behnisch's Genzyme building) and derives principles influencing future architecture practice. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2005.; Includes bibliographical references (p. 136-139).

Puja Pandals : rethinking an urban bamboo structure

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Puja Pandals : rethinking an urban bamboo structure Oza, Nilay Pandal's are large tent like structures that are recreations of popular buildings, usually temples, built in wood and cloth over a bamboo super-structure. Traditionally they are built for Durga Puja, a festival in the month of October in parts of Eastern India. Today these structures have become expressions of a broader popular culture where themes both religious and non-religious are played out. Building on research on Pandal's this study contends that, with certain modifications, bamboo could be used to construct cost-effective, large span, temporary structures in Urban South Asia. It is also contented that the abundance and availability of bamboo has, to an extent, worked against its intelligent use. Any degree of structural innovation is deemed unnecessary as it is not considered commensurate with its cheap availability. Here the material is valued for its qualities and is not premised on its obvious use and expendability. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2000.; Includes bibliographical references (leaf 40).

Equilibrium systems : studies in masonry structure

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Equilibrium systems : studies in masonry structure Block, Philippe (Philippe Camille Vincent) This thesis presents new interactive computational analysis tools for masonry structures based on limit state analysis. Thrust lines are used to clearly visualize the forces within the masonry and to predict possible collapse modes. The models are interactive and parametric to explore the relation between the different geometrical parameters and the possible equilibrium conditions. Collapse mechanism analyses are determined by combining kinematics and statics. Complex three-dimensional problems are analyzed using the same methods. This thesis presents a series of analysis tools that are fast and easy to use, but at the same time rigorous and highly accurate. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2005.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Includes bibliographical references (leaves 38-40).

Deployable structures inspired by the origami art

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Deployable structures inspired by the origami art Giesecke, Ken, 1976- My thesis is an exploration of design methods and tools using origami as a vehicle to test their usefulness and coming to terms with their limitations. I have taken my fascination with a particular development in origami and put my belief in its potential for architectural application to the test by way of various investigations: materials and structural analysis, mathematical reasoning, manipulating space and form, parametric modeling, fabrication, and finite element testing. Parting from conventional, figural forms, mathematicians developed open-surface forms together with theorems that governed the ability of these folded forms to fold flat. I selected a particular form, the Kao-fold, for its simplicity, beauty, and structural properties and imagined many exciting possibilities, specifically for its application in designing a deployable structure. I analyzed its crease pattern, exploring variations and their corresponding folded forms. Simultaneously, different material ideas for larger-scale structures were tested and a particular configuration was assessed for internal stresses and its structural stability. Its transformation from a flat sheet to a folded state was scrutinized under the lens of mathematical reasoning, namely trigonometry, by linking the acute angle of its crease pattern and the dihedral angle in its folded state to its final folded configuration. The rigidity of this investigation was offset by the freedom afforded in manipulating paper models. As such, different spatial qualities and forms were explored while addressing the issue of scale and potential applications.; (cont.) The transformational characteristics discovered were digitally simulated via the construction of parametric models, which was a more controlled manipulation of the form in a virtual space. In order to go beyond the realm of representation and address real-life building issues, a temporary open-air shelter was designed and constructed in detail. The goal was to tackle the complexity of assigning materials, designing components and fabricated them. As a final endeavor, the model's construction was tested for its structural stability using a finite element software. Thesis (M.Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 2004.; Includes bibliographical references (p. 60-63).

Flexibility in building design : a real options approach and valuation methodology to address risk

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Flexibility in building design : a real options approach and valuation methodology to address risk Greden, Lara V. (Lara Virginia), 1977- This research develops an approach to designing and valuing flexible systems subject to identified future uncertainties. The approach addresses two shortcomings of current design and decision-making practices that are particularly evident in the buildings industry: 1) systems are designed as though they will remain as static entities despite existing in uncertain environments, and 2) typical decision-making methods, such as net present value and life-cycle costing, do not recognize uncertainty and the ability to make decisions in the future as uncertainties are resolved. The flexible design approach produces an improved design result by addressing the risks and opportunities induced by uncertainty. Two applications relevant to sustainable building design are developed to demonstrate the approach. First, the value of the flexibility to change the use of a space, thereby increasing building longevity and reducing waste, is evaluated. Option value is defined as the savings of low renovations costs as compared to the cost of renting space on the market. Uncertainties include the market price of rent, timing, amount of space needed, and number of renovations. It is shown that higher upfront investment leading to reduced cost for future change is economically justified in certain scenarios. The value of flexibility increases with increased time horizon and increased uncertainty in the market price of rent. The Black-Scholes formula can be used to approximate the value of flexibility in some cases. Second, the risk of employing an innovative technology is addressed with a flexible design that provides a fallback position.; (cont.) Specifically, the risk that a naturally ventilated (NV) building becomes overheated in the future due to climate uncertainty is addressed with an option to install mechanical cooling (MC). A model that simulates the system's technical performance under uncertainty demonstrates the value of the option. It is shown that in some locations, increased climate variability does not reduce the viability of NV (i.e., the option to install MC remains unexercised). The likelihood of installing MC is sensitive to design parameters. The results also demonstrate the benefits of the flexible, NV building as compared to MC: delayed or avoided capital costs (e.g., chillers) and cooling energy savings. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2005.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Includes bibliographical references (p. 223-232).

An indoor public space for a winter city

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An indoor public space for a winter city Crane, Justin Fuller Winter is a marginalized season in North American design. Even though most cities in the northern United States and Canada have winter conditions-snowfall, ice, freezing temperatures, and long nights-for substantial portions of the year, their built environments do little to embrace their climate. Architecture confronting the problems of design for a winter city must have two complementary components-a social one that addresses comfort and the interaction between the public and private realms, and a technical one that addresses energy- efficiency. First, winter cities lack equitable and attractive indoor places of refuge from the elements. The most common contemporary response to the climate is to create huge commercial developments. These take the form of free-standing megamalls or networks of indoor storefronts winding through downtowns via tunnels and elevated skyways. These draw people who can afford to shop away from the public realm while leaving city streets deserted. Second, winter cities use superlatively high amounts of energy for heating, and this consumption continues to grow as a result of sprawling suburbs and generic building that disregards its context. The proposed mediatheque for St. Paul, Minnesota confronts these problems by using thermal qualities as a driver for its design. Like winter, thermal qualities are an often ignored factor in architecture. However, by using them to shape space, choose materials, and complement social interaction, the design for an indoor urban space will welcome all members of the public, use energy responsibly, and celebrate diverse activities throughout the day and the year. Thesis (M. Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 2005.; Includes bibliographical references (p. 90-93).

Houses in Heaven are made of steel : understanding change in Ecuadorian amazon Secoya structures

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Houses in Heaven are made of steel : understanding change in Ecuadorian amazon Secoya structures Arboleda, Gabriel This thesis explores the change in the building structures of a Northeastern Ecuadorian group, the Secoya of the Aguarico River. In the context of environmental activism and cultural survival there are many reasons to lament major alterations in the Secoya's lifestyle in recent years. One of the most visible transformations experienced by this group is the abandonment of several traditional architectural types, including the Jaihub'e or communitarian longhouse. The thesis focuses on understanding the forces that have influenced the Secoya decision to adopt the Zinc House type, a metallic-roofed individual housing unit. These include change in their economic systems, depletion of the natural resources necessary for traditional construction, Western cultural pressure, difficulty to adapt the traditional structures to a modern life, and finally a historical predisposition to change. In short, the Secoya changed firstly because everything around changed, leaving them with no other option, and secondly because, simply, human beings naturally tend to change. The change was meaningful for the Secoya because many building practices that were actively linked to social life were abandoned. It was meaningful for us outsiders because our expectations of an exotic culture were left unfulfilled when it changed. However, rather than the loss of another indigenous culture, what the case illuminates is the nature of our own expectations, those conforming to an urban, pop mythology regarding sustainability. We should follow the Secoya example and change our own urban mythology, because our mythology wrongly overvalues cultural idleness and nature as the means for guaranteeing sustainability;; (cont.) it emphasizes that sustainability depends on resource saving rather than on social justice, and it believes that sustainable solutions are an universal panacea that invariably applies to every culture, geography and historical context. The thesis seeks to expand the frontier of architectural theory towards an unconventional scenario, that of the Upper Amazon, in a series of specific topics: First, it provides detailed knowledge on three typologies of ethnic interest, one of them aboriginal (locally originated), one indigenous (locally adapted) and one modern (neutral-global). Second, it offers historical knowledge about the evolution of the Upper Amazonian building tradition. Third, it discusses how myth and building structure interact in the Upper Amazonian traditional house. Fourth, it details the serious cultural implications of the abandonment of the traditional types. Five, it presents knowledge about the environmental and social factors contributing to the abandonment of those types. And six, it helps to develop awareness about our own urban myths on sustainability in the context of change. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, June 2005.; Includes bibliographical references (p. 132-135).

Model identification with application to building control and fault detection

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Model identification with application to building control and fault detection Armstrong, Peter Ross, 1950- (cont.) may still be solved as an unconstrained linear least squares problem. To enforce the constraint on system eigenvalues, the problem is formulated as an unconstrained mixed (linear and non-linear) least-squares problem, which is easier to solve than the corresponding problem with linear objective function and non-linear constraints. The (usually unfounded) assumption on which the normal equations are based--that observations of the independent variables are error free--is relaxed at the cost of one more non-linear term. The resulting model coefficients are valid for predicting heat rate given zone temperature as well as for predicting zone temperature given heat rate. Control. Three important control applications involving transient zone thermal response are HVAC curtailment, optimal start, and night precooling. A general framework for model-based control of zone and whole-building operation is developed. Optimal precooling under time-of-use rates is formulated to solve the optimal fan operation sequence using a one-day control horizon with hourly time steps. Energy and demand cost savings are presented.; Motivated by the high speed of real-time data acquisition, computational power, and low cost of generic PCs and embedded-PCs running Linux, this thesis addresses new methods and approaches to fault detection, model identification, and control. Fault detection: A series of faults was introduced into a 3-Ton roof-top air-conditioning unit (RTU). Supply and condenser fan imbalance were detected by changes in amplitude spectrum of real power resulting from the interaction of impeller rotation and the dominant chassis vibration mode. Ingestion of liquid refrigerant by the compressor was identified by detecting power and reactive power transients during compressor starts. An adaptive ARX(5) model was used to detect ingestion during steady compressor operation. Compressor valve or seal leakage were detected by a change in the leakage parameter of a simple evaporator-compressor-condenser model that explains the rise in compressor load from 0.25 to .5 seconds after compressor start, i.e. as shaft speed rises from about 50% to 90% of synchronous speed. Refrigerant undercharge was also detected by changes in start transient shape. Overcharge was detected by steady state compressor power and reduced evaporator and condenser air flow were detected by steady state power draw of the respective fan motors. Model Identification. On-line models are useful for control as well as fault detection. Model-based control of building loads requires a valid plant model and identification of such a model for a specific building or zone is a non-trivial inverse problem. The thesis develops three advances in the thermal diffusion inverse problem. Two involve thermodynamic constraints. The problem is first reformulated in such a way that the constraint on temperature Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2004.; Includes bibliographical references (p. 110-115).

FLUX : adaptable architecture for a dynamic society

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FLUX : adaptable architecture for a dynamic society Greene, Aaron Steven Wendel, 1978- (cont.) Perhaps a more functional architecture that is kinetic, transformable, capable of disengagement, and reassembly could keep up with the occupants' need to have multiple programs taking place in one space, maintain economy, and alleviate the over use of energy and resources.; Contemporary society is being re-defined by continuous travel and motion, resulting in the collapse of time and space--the origins of globalization, and infinite, never ceasing data transfer; both of which have propelled us into the Information Age. The resulting cultures are hybrid, more complex, and always transforming. As corporations and communities continue to expand and contract, re-locate, emerge, and vanish, their need to be capable of adapting is increasing. On Monday, the client desires a mid-rise building with an open floor plan on all levels. The following Wednesday, his company's stock has gone through the roof and his financial advisors suggest a mixed use facility, with retail space on the lower three levels and ten extra floors of office space. By Friday, his architect will have designed a sky-scrapper. These fast pace changing needs, the various forms of infrastructure that facilitate transfer, and evolving technology confront architects with a major question. Can architecture become flexible, adaptable, and transformable in order to meet the ever-changing demands of contemporary society? Infrastructure permeates every facet of our lives. It allows us to move to here and there, it brings resources, data, and entertainment to our very fingertips. It operates at various scales, and even provides stability within society. The thought of architecture fusing with or becoming like infrastructure is not a new subject matter, theorist have written about it for years. The human species has always been transient, so why the need for a new architecture? Our new technologies have also prompted the degradation of our global environment, and caused the over utilization of various natural resources. Thesis (M. Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 2004.; Includes bibliographical references (p. 99-102).

TALL : rethinking the systems of the contemporary high rise

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TALL : rethinking the systems of the contemporary high rise Namkung, Kenneth, 1977- The life of modern work is complex. What once entailed simple activities encapsulated within simple and hierarchically designed spaces has evolved into a highly volatile and complex organism. Businesses and workers are increasingly mobile, unpredictable and collaborative, requiring new types of spaces to correspond to new methods of working. While there has been much recent interest in the design of the workplace and on flexible, efficient and wired office environments, this focus has lead to the development of innovative interior systems and infrastructures that are typically inserted into rather generic architecture. This schism between complex program and simple space is most evident in the typology of the tall office building. Repetitive stacked slabs built to conservative economic programs create appallingly generic environments. In other words, the skyscraper is typically conceived as a homogenous container for heterogeneous activity. This thesis hypothesizes that the typology of the skyscraper can be redesigned to accommodate a more complex series of spaces designed around the needs of modern office culture, and that this complexity can be manifested in architectural form. This is accomplished using a multipronged research methodology. The first component is an analysis of the spatial types found in the office. The second component is a new inhabitational model that accommodates multiple occupational modes. The third component is a flexible architectural system that accommodates sectional variation and organizational change through on-site maintenance and reconstruction. The fourth component utilizes emergent technologies in architecture to rethink the skin of the office building as a dynamic and permeable object that incorporates multifunctional environmental buffer spaces. These intersecting agendas are manifested in the form of a sixty floor office tower located in midtown Manhattan. The end result of this process is not a focused research inquiry into a singular agenda but is rather" a prototype that innovates at many scales, and does so in a way that fits within economic necessities of large scale office development. Thesis (M.Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 2003.; Includes bibliographical references (p. 86-87).

Radiative transfer and thermal performance levels in foam insulation boardstocks

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Radiative transfer and thermal performance levels in foam insulation boardstocks Moreno, John David The validity of predictive models for the thermal conductivity of foam insulation is established based on the fundamental geometry of the closed-cell foam. The extinction coefficient is experimentally and theoretically determined; the theoretical prediction based on measured geometrical properties differed from the measured values by an average of 6% for ten different foams An approximate method uses measured geometrical values to adjust the measured diffusion coefficients of reference foams. The adjusted coefficients are used as inputs to a computer program which computes the effective thermal conductivity of the foam as a function of time. Values of effective thermal conductivity measured on laboratory and field samples are used as a standard for comparing the results of the physical models and the ageing program. Measured and predicted values differ by 11%, 13%, 1%, 5%, and 1% for the initial thermal conductivity of five foams tested. These errors decrease with time. The ageing program is used to simulate the time-averaged performance as a function of foam density, mean cell diameter, and fractional distribution of solid polymer. The results of the simulation indicate that for a 15 year service life, the optimal density is approximately 3 lb / ft3. Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1991.; Includes bibliographical references (leaves 82-83).

Soundfield simulation : the prediction and validation of acoustical behavior with compute models

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Soundfield simulation : the prediction and validation of acoustical behavior with compute models Saad, Omar, 1974- In the past, acoustical consultants could only try to convince the client/architect that with calculations and geometrical plots they could create an acoustically superb space. Now, by modeling the significant acoustical parameters of a design, we can preview a proposed acoustical solution and it is possible to identify the objective parameters that correspond to certain subjective reactions experienced by listeners. The results of a simulation can be presented not only for the eyes but also for the ears. This document explains the basics behind acoustic computer simulation. It includes case studies that analyze and validate numerical parameters and create a sound simulation of a space that allows the listener to subjectively "grade" the acoustical qualities. It includes details on how human hearing uses several techniques to localize sound sources, how we can simulate factors that influence human auditory perception with computer software, and how we can reproduce the listening experience for a space that has not been built. The simulation techniques offer the possibility to use the ears and listen to the acoustics of a room during the design process. Several acoustic problems can be detected by the ears, whereas they may be difficult to express with a parameter that can only be calculated. Using these tools the acoustician can communicate the acoustic consequences of a design to the client/architect effectively. This technique can be used very early in the project to achieve exceptional results. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2004.; Includes bibliographical references (leaves 56-58).

An analysis of residential window waterproofing systems

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An analysis of residential window waterproofing systems Parsons, Austin, 1959- The prevalence of vinyl nail-on windows in the North American new home construction market has prompted ASTM International to write ASTM E2112-01 "Standard Practice for Installation of Exterior Windows, Doors and Skylights". This thesis focuses on the window jamb flashing recommendation in ASTM E2112-01 for vinyl nail-on windows by asking the question of whether a vinyl window's integral nail-on flange is by itself an adequate jamb flashing. To answer this question, the Jamb Drip Test was designed and completed on fourteen (14) window/wall details. The answer to the question depends on the window/wall construction sequence. When the weather resistant barrier (WRB) is installed prior to the window, it isn't. When the WRB is installed after the window, the nail-on fin is by itself an adequate jamb flashing. Based on this Jamb Drip Test study, a recommended window/wall construction sequence of sheathing- flashing (sill, jamb and head) - vinyl nail-on window - WRB - siding option is proposed. This sequence recognizes that while the nail-on fin may be an adequate jamb flashing, without flashing, the designer cannot take full advantage of the symbiotic relationship between the nail-on flange and the space it creates between the adjoining building elements (e.g. sheathing and the WRB). In this capacity, jamb flashing is added to the construction sequence to protect the sheathing from wetting and aid in directing incidental water to the exterior. Based on this proposed construction sequence, effort was focused on improving the present state of the art window/wall weatherproofing detail. An alternative to the use of high performance sealant to create the seal between the flashing and the window's nail-on flange is proposed. The present recommendation uses a; (cont.) one-piece folded sheet that envelops the window flange, WRB and at the same time incorporates the window flashing function. This novel, dual function (window seal + window flashing system) product is called w-Flashing. The thesis ends with a description of w-Flashing's performance attributes, prototype design and recommended installation sequence around a vinyl nail-on window. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2004.; Includes bibliographical references.

The use of coated micropowders to reduce radiation heat transfer in foam insulation

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The use of coated micropowders to reduce radiation heat transfer in foam insulation Marge, Arlene Lanciani Polyurethane foam is the most effective insulation currently available for buildings. Chlorofluorocarbon (CFC) blowing agents, which have low thermal conductivities, contribute highly to the effectiveness of this insulation. However, CFC blowing agents are being phased out because they are depleting the earth's protective ozone layer. Alternate blowing agents, with higher thermal conductivities, will compromise the insulating value of the foam insulation. To counteract this effect, the author has sought to improve the effectiveness of foam insulation by increasing its extinction coefficient. In this work, theoretical analysis and experimental measurements have been used to study and increase the extinction coefficient of polyurethane foam insulation. Radiative heat transfer, which accounts for approximately 25% of the total heat transfer through foams, is inversely proportionate to the extinction coefficient. Foam cell walls presently have a transmissivity of about 80% to infrared radiation. The extinction coefficient of foams can be improved by decreasing the cell sizes or by increasing the absorptivity of the foam cell walls. The approach of this work has been to increase the cell wall opacity through the addition of opaque micropowders. Conduction through the solid polymer is of the same magnitude as the radiative transfer, also accounting for approximately 25% of the heat transfer of the foam. To maintain the low thermal conductivity of the polymer, the micropowders added to reduce radiative transfer through the foam must not change its characteristic conductivity. Polymer micropowders with thermally opaque coatings of graphite have been developed in this work using core micropowders with diameters between 8 and 30 [mu]m. Theory predicts that the smaller the particle size, the larger the resulting improvement in extinction coefficient. The coatings required for opacity are less than 0.1 [mu]m thick, composing less than 7% of the overall volume of the powder. The extinction coefficients of the coated micropowders have been experimentally derived and agree well with analytical predictions. These coated micropowders have been added to foams with the goal of increasing their extinction coefficients. The resulting foams indeed demonstrate improved extinction coefficients when compared to a powderless control foam. This improvement results both from reduction in cell size and increased cell wall opacity. The resulting effective conductivities of the foams have been decreased by as much as 6% through the addition of these relatively large micropowders. These results correlate well with predicted values and indicate that the addition of smaller particles will result in even more improvement. Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1991.; Includes bibliographical references (leaves 126-129).

Reworking the city of workers : a new housing paradigm for the immigrant city

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Reworking the city of workers : a new housing paradigm for the immigrant city Butler, Britta Erika, 1974- The climate of the reception of immigrants to the United States has soured, and circumstances are becoming increasingly difficult for persons seeking to gain residency. Reasons often given for the reversal in this practice are that immigrants are poor, uneducated, take jobs away from Americans, and use valuable resources otherwise available to the native-born. This at-best cautionary condition is unfortunate, not only because it decreases diversity in a society already afraid of "the other", but because the US is the very model founded on foreigners trying to make lives for themselves. In evidence now is a disdain and distrust of foreigners that could eventually affect all people in the US, resulting in an atmosphere of suspicion and negativity toward anyone who is perceived as different. This design thesis posits that immigrants are important additions to local neighborhoods and economies. If they are supported physically and psychologically during their initial period of arrival, they can more readily become integral members of American society. The design of housing, a learning center, and incorporation of the arts becomes a new means by which immigrants can retain ties to their cultural heritage, while concurrently increasing self-sufficiency, dispelling ignorance, and fostering greater acceptance and knowledge in the community at large. Thesis (M.Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 2003.; Includes bibliographical references (p. 71).

Informed home energy behavior : developing a tool for homeowners to monitor, plan and learn about energy conservation

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Informed home energy behavior : developing a tool for homeowners to monitor, plan and learn about energy conservation Stigge, Byron J. (Byron John), 1977- Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2001.; Includes bibliographical references (p. 76-78).

Green building technologies : should a developer implement photovoltaics, underfloor air distribution, and natural ventilation?

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Green building technologies : should a developer implement photovoltaics, underfloor air distribution, and natural ventilation? Donovan, Richard J. (Richard James), 1974- This thesis explores implications of green, or environmentally sensitive, development in the commercial real estate industry. Developers, as building owners, will respond to ideas that can improve their profits, not necessarily to an environmental call to arms. The ability to lease up a development quickly is a competitive advantage that a developer can realize as increased net operating income. Green building strategies may increase the productivity of occupants, which may also help a developer differentiate a project from the competition. Three green building technologies, underfloor air distribution, photovoltaics, and natural ventilation, are examined in detail to determine if they are financially feasible for a developer to include in a commercial real estate office project. This thesis attempts to use a financial argument, to address the issue of environmental sustainable, or green, development. The results of the study are that natural ventilation and underfloor air distribution are currently promising technologies that should be seriously considered by developers. The high cost of photovoltaics, however, does not justify their current use in a commercial development. A large part of the decision to include green developments is dependent on the developer understanding his/her clients, the tenants. This thesis includes a survey of both developers and tenants in an effort to gauge their interest in green technologies and willingness to pay for them. The results of the survey are presented, and suggestions for the future of green building practices are laid out. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2001.; Includes bibliographical references (p. 61-64).

An evolution-based generative design system : using adaptation to shape architectural form

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An evolution-based generative design system : using adaptation to shape architectural form Caldas, Luisa Gama (Maria Luisa da Oliveira Gama Caldas), 1968- This dissertation dwells in the interstitial spaces between the fields of architecture, environmental design and computation. It introduces a Generative Design System that draws on evolutionary concepts to incorporate adaptation paradigms into the architectural design process. The initial aim of the project focused on helping architects improving the environmental performance of buildings, but the final conclusions of the thesis transcend this realm to question the process of incorporating computational generative systems in the broader context of architectural design. The Generative System [GS] uses a Genetic Algorithm as the search and optimization engine. The evaluation of solutions in terms of environmental performance is done using DOE2.1E. The GS is first tested within a restricted domain, where the optimal solution is previously known, to allow for the evaluation of the system's performance in locating high quality solutions. Results are very satisfactory and provide confidence to extend the GS to complex building layouts. Comparative studies using other heuristic search procedures like Simulated Annealing are also performed. The GS is then applied to an existing building by Alvaro Siza, to study the system's behavior in a complex architectural domain, and to assess its capability for encoding language constraints, so that solutions generated may be within certain design intentions. An extension to multicriteria problems is presented, using a Pareto-based method.; (cont.) The GS successfully finds well-defined Pareto fronts providing information on best trade-offs between conflicting objectives. The method is open-ended, as it leaves the final decision-making to the architect. Examples include finding best trade-offs between costs of construction materials, annual energy consumption in buildings, and greenhouse gas emissions embedded in materials. The GS is then used to generate whole building geometries, departing from abstract relationships between design elements and using adaptation to evolve architectural form. The shape-generation experiments are performed for distinct geographic locations, testing the algorithm's ability to adapt buildings shape to different environments. Pareto methods are used to investigate what forms respond better to conflicting objectives. New directions of research are suggested, like combining the GS with a parametric solid modeler, or extending the investigation to the study of complex adaptive systems in architecture. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2001.; Includes bibliographical references (leaves 284-291).

Detection and diagnosis of faults and energy monitoring of HVAC systems with least-intrusive power analysis

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Detection and diagnosis of faults and energy monitoring of HVAC systems with least-intrusive power analysis Luo, Dong, 1966- Faults indicate degradation or sudden failure of equipment in a system. Widely existing in heating, ventilating, and air conditioning (HVAC) systems, faults always lead to inefficient energy consumption, undesirable indoor air conditions, and even damage to the mechanical components. Continuous monitoring of the system and analysis of faults and their major effects are therefore crucial to identifying the faults at the early stage and making decisions for repair. This requires the method of fault detection and diagnosis (FDD) not only to be sensitive and reliable but also to cause minimal interruption to the system's operation at low cost. However, based on additional sensors for the specific information of each component or black-box modeling, current work of fault detection and diagnosis introduces too much interruption to the system's normal operation associated with sensor installation at unacceptable cost or requires a long time of parameter training. To solve these problems, this thesis first defines and makes major innovations to a change detection algorithm, the generalized likelihood ratio (GLR), to extract useful information from the system's total power data. Then in order to improve the quality of detection and simplify the training of the power models, appropriate multi-rate sampling and filtering techniques are designed for the change detector. From the detected variations in the total power, the performance at the system's level is examined and general problems associated with unstable control and on/off cycling can be identified. With the information that are basic to common HVAC systems, power functions are established for the major components, which help to obtain more reliable detection and more accurate estimation of the systems' energy consumption. In addition, a method for the development of expert rules based on semantic analysis is set up for fault diagnosis . Power models at both system and component levels developed in this thesis have been successfully applied to tests in real buildings and provide a systematic way for FDD in HVAC systems at low cost and with minimal interruption to systems' operation. Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2001.; Includes bibliographical references (p. 171-175).

Properties and applications of double-skin building facades

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Properties and applications of double-skin building facades Arons, Daniel M. M., 1966- A new era of commercial buildings is emerging in Europe, driven by innovative designs in Germany, Britain and the Netherlands. Engineers and Architects are collaborating to design a new typology of buildings that are energy efficient, environmentally friendly, and architecturally sleek. The common elements are double-skin facades (DSF's) that employ sun shading and air movement between inner and outer glass membranes. The doubleskin or "airflow" facade is tied to mechanical systems either physically with ducts or by significantly affecting the performance of those systems by reducing building loads. As compared to conventional facade systems, DSF's are credited with providing a 30% reduction in energy consumption, providing for natural ventilation even in skyscrapers, and providing valuable noise reduction. They also create a visually transparent architecture that is impossible with conventional curtain wall facades with similar properties. However, most building owners, architects and engineers do not have the language or analytical tools to analyze the appropriateness of this technology to buildings of varying occupancies and configurations and in various climates. Double-skin facades are defined and a typological system is proposed as a quick reference tool that will aid in understanding and communicating about the family of solutions that lie within a family of technologies that fit the definition of DSF's. A series of case studies examines a range of DSF typologies and analyzes their goals, structure, and relative success. An analytical model is developed and described to provide a flexible tool for evaluating energy impacts of a wide range of double-skin facade designs. A parametric analysis suggests how this model may be used as a design tool by emphasizing key properties of DSF systems. The analysis and model is applied to the potential technology transfer to Tokyo, Japan. Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2000.; Includes bibliographical references (p. 267-273).

Numerical solution of nonlinear algebraic systems in building energy modeling

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Numerical solution of nonlinear algebraic systems in building energy modeling Lorenzetti, David Michael When solving a system of nonlinear equations by Newton-Raphson's method, a common means of avoiding divergence requires each step to reduce some vector norm of the residual errors, usually the convenient and tractable sum of squares. Unfortunately, the descent requirement subjects the solver to difficulties typically associated with function minimization-- stagnation, and convergence to local minima. The descent requirement also can disrupt a successful Newton-Raphson sequence. To explore these problems, the thesis reformulates the theory of function minimization in terms of the familiar Jacobian matrix, which linearizes the equations, and a vector which relates first-order changes in the norm to first-order changes in the residuals. The resulting expressions give the norm's gradient, and approximate its Hessian, as functions of the key variables defining the underlying equations. Therefore when Newton- raphson diverges, the solver can choose a reasonable alternate search strategy directly from the Jacobian model, and subsequently construct an appropriate norm for evaluating the search. Applying these results, the thesis modifies a standard equation-solving algorithm, the double dogleg method. Replacing the published algorithm's r-square norm with a general family of weighted r-square norms, it develops and tests a variety of rules for choosing the particular weighting factors. Selecting new weights at each iteration avoids local minima; in tests on a standard suite of nonlinear systems, the resulting algorithms prove more robust to stagnation, and often converge faster, than the double dogleg. In separate investigations, the thesis specializes to equation-solving a double dogleg variation which minimizes the norm model in the plane of its steepest descent and Newton-Raphson directions, and develops a scalar measure of divergence which, unlike a residual norm, does not depend on results from function minimization. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture and Planning, 1997.; Includes bibliographical references (p. 249-251).

Energy efficiency in office technology

2022-01-13T07:54:11Z

Energy efficiency in office technology Dandridge, Cyane Bemiss This thesis, directed toward a wide variety of persons interested in energy efficiency issues with office technology, explores several issues relating to reducing energy use and improving energy efficiency of office equipment. Chapter 2 compares policies and programs in several European countries and the United States that could enhance the energy efficiency of office technology. Different programs are examined, including federal government programs where in some cases target values for power usage of office equipment have already been set. Large customer procurement programs, industry involvement, with emphasis on voluntary labeling programs, and research projects are also examined. Procedures that provide energy consumption measurements of various types of equipment are important for providing information to emerging procurement programs. Two sets of proposed test procedures for testing energy consumption of copiers, fax machines and printers are examined and compared. In Chapter 3, comparisons are made of the electrical power and energy used by computers, displays, copiers, printers and facsimile machines, both while operating and while idle. Technology options for reduced energy and power consumption and improved energy efficiency are examined. As the capability of office equipment has increased, there has been a trend toward increased electrical power requirements and energy consumption while equipment is in active operation. Computer power continues to grow rapidly. These factors will combine to exert an upward pressure for electrical power. However, some emerging technologies are lessening or in some cases reversing this trend, with little or no penalty in performance or production. The overall balance between increased service and efficiency is uncertain. Chapter 3 also examines the embodied energy of paper and office equipment. I compare it to the total energy required to produce a printed page of information, or required over the lifetime of the machine. Many difficulties were encountered in collecting and comparing data on power requirements of various machines. Procedures for testing the energy usage of office equipment are needed to make valid comparisons between machines. This thesis describes in Chapter 4, modifications to the procedure issued by the American Society for Testing and Materials (ASTM) to test energy consumption in copiers, to account for energy saver modes and double-sided copying. It also presents new procedures submitted to the ASTM committee for printers and fax machines. A fourth procedure is also presented here, one to test the energy consumption of personal computers. Typically, office equipment is not in use for much of the time it is turned on. Use of power management in office equipment can considerably decrease overall energy consumption. While energy saver modes are more prevalent in copiers, those printers that have incorporated this feature achieve more dramatic power reductions. Fax machines do not seem to utilize this technology at all, even though many have high power consumption when they are idle. How energy saving modes effect the overall energy consumption of machines is largely determined by operating profiles of the machines. The effect of operating profiles on energy usage with imaging equipment has not yet been examined. Methods of determining operating profiles of office equipment are presented in Chapter 5. A comparison is made between the energy use predicted by the ASTM procedures, energy use predicted by the ASTM procedures and actual operating profiles, and the actual energy usage of several copiers and printers. For copiers, the ASTM rated energy use per page was from 10-161 % different from the actual measured energy use per page. The use of the ASTM method with the measured operating profiles of the machine gave a 7-22% difference in energy use per page. For printers, the rated values using the ASTM method gave 61-317 % difference from the actual measured energy use per page, while using actual usage profiles with the ASTM method gave 0-6% difference. This thesis provides information on a variety of subject in the area of energy use and energy efficiency in office technology. The results provide information for emerging programs and provide a strong basis for a variety of further research. Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1994.; Includes bibliographical references (leaves 204-210).

Building load control and optimization

2022-01-13T07:54:12Z

Building load control and optimization Xing, Hai-Yun Helen, 1976- Researchers and practitioners have proposed a variety of solutions to reduce electricity consumption and curtail peak demand. This research focuses on load control by improving the operations in existing building HVAC (Heating, Ventilating and Air-Conditioning) systems and by aggregating individual loads based on optimization studies. Emphasis is placed on electricity rates and climate data in California, where electricity costs have been of particular concern. The optimization problem in this research is multi-objective in the sense that we aim to reduce building load while maintaining an acceptable level of comfort. The first part of this research focuses on optimizing controls in a single building. A simple three-zone VAV system model is built in EnergyPlus (E+). The cost function structures and the potential difficulties associated with simulation-based optimization are discussed. Discontinuity and nonlinearity are of major concern. Two optimization algorithms are tested and applied to a variety of problems: Direct Search (DS) and Genetic Algorithms (GA). An E+ simulation based GA optimization environment is developed in Matlab. DS is found to be efficient with small problems in this research, while GA works in almost any situation with the price of intensive computation. A few operations guidelines are proposed. The second part of this research presents three ways of optimizing load control in an aggregation pool: Enumeration, multi-GA and model-based nonlinear optimization. Enumeration relies on expert rules to find a small set of feasible solutions through automated E+ simulations and search exhaustively for the optimal solution. Multi-GA solves the aggregation problem in the Matlab GA environment with; (cont.) sequential E+ simulations as the function evaluator. Because simulation-based optimization is very computationally intensive in handling multiple buildings, the model-based approach develops for each aggregation participant a time series model and several regression models to predict individual load profiles under load control. It then applies an interior-point-method-based commercial solver LOQO to these simplified building models. This system is fast and easy to scale up. Certain precision is lost due to modeling simplifications, but the results are still satisfactory for practice purposes. Overall, load aggregation offers load diversification opportunities among participants and improves the aggregated load profile. Load shedding later individual load profiles in a way that enhances the aggregation performance. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2004.; Includes bibliographical references (p. 185-188).

Developing an integrated building design tool by coupling building energy simulation and computational fluid dynamics programs

2022-01-13T07:54:12Z

Developing an integrated building design tool by coupling building energy simulation and computational fluid dynamics programs Zhai, Zhiqiang, 1971- Building energy simulation (ES) and computational fluid dynamics (CFD) can play important roles in building design by providing essential information to help design energy-efficient, thermally comfortable and healthy buildings. However, separate applications of ES and CFD usually cannot give an accurate prediction of building thermal and airflow behaviors due to the partial modeling of the problem. An integration of ES and CFD can eliminate many of the assumptions used in ES and CFD because of the complementary nature of ES and CFD results. This thesis studies the fundamentals, implementation and application of ES and CFD coupling, significantly advancing the knowledge and experience in this area. The study has been focused on the iterative coupling of individual ES and CFD programs, which shows good potential of providing reasonable results with acceptable computing costs. The research first analyzes the principles and challenges of ES and CFD program coupling. To bridge three major discontinuities in time-scale, spatial resolution and computing speed between ES and CFD programs, special coupling strategies have been developed. Particularly, the staged coupling strategies proposed can effectively reduce computing time while preserving the accuracy and details of the computed results. The study discusses the solution characteristics of iterative coupling simulation. Through theoretical analysis and numerical experiments, the research verifies the solution existence and uniqueness of a coupled simulation. The investigation concludes that a converged and stable simulation can be achieved with four different data coupling methods. The study has further developed an improved iteration and control algorithm for the coupled simulation. An integrated program, E+MIT-CFD, has been developed by coupling a new- generation ES program (E+) with a newly-developed ready-to-plug-in CFD solver (MIT- CFD). All the coupling methods and strategies proposed have been implemented in this program. The program has been well validated with various experimental facilities. The comparison of numerical solutions with experimental data reveals the advantages of the integrated simulation over the separate ES and CFD applications. The study further demonstrates the performance and capabilities of the coupled program through practical; (cont.) through practical design projects. Finally, sensitivity analysis of the coupling simulation to building characteristics and coupling strategies has been performed, based on which general guidelines are established for appropriate usage of the coupling simulation. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2003.; Includes bibliographical references (p. 237-246).

Field crossings : hybridizing the urban park

2022-01-13T07:54:12Z

Field crossings : hybridizing the urban park Cyphers, Scott M The growth and identity of urban open space is a vital issue facing our cities today. The development and revitalization of old industrial centers in the United States has prompted urban transformations in usage, densification and demographics. These shifting neighborhoods call for a reconsideration of the makeup and syntax of their associated green spaces. The design of this urban landscape is not currently positioned to take advantage of limited spatial opportunities while meeting increasingly diverse programmatic needs. Traditional park typologies must respond to contemporary forces, varying leisure practices and allow for new interactions with an evolving city. This thesis posits a new model for parks and their architecture within changing urban neighborhoods. It explores how parks can accommodate these transformations through the topics of imbedded infrastructure, flexibility, prototyping and merging public and private usage. It seeks to create more humane and vital open spaces by adding functional and diversified occupations that respond to specific contextual requirements. This thesis looks to understand how both the landscape and its built architecture can work together to become a more viable model for the next century. Thesis (M.Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 2003.; Includes bibliographical references (p. 102-103).

Experience of light : the use of an inverse method and a genetic algorithm in daylight design

2022-01-13T07:54:12Z

Experience of light : the use of an inverse method and a genetic algorithm in daylight design Chutarat, Acharawan Integration of daylight availability in time and architectural space is a critical element in achieving optimal comfort and productivity, as well as in minimizing energy consumption. In recent years, there has been an increase in the demand of the better quality of the built environment. Accessibility and availability of information do not assurance success in design. There is a gap between available information and design team. A critical understanding of the issues that affects design and its process needs to be developed. Successful strategies require the participation of individual users and designers in configuring built environments and needs. Before proposing a new solution, success factors and methodology have been identified. There are many problems-solving techniques associated with design and delivery systems. Most popular techniques are forward methods and typically employed "trial and error" processes, attacking problems on the front end first. On the other hand, a problem-solving technique called the inverse method seems to be efficient. It starts with designer's goals and then identifies a design to meet those goals. In an effort to provide optimum choices in daylighting design, this thesis emphasizes the use of scientific-knowledge computational tools in the later stages of design employing the inverse method. The genetic algorithm (GA) is applied to search for optimal daylighting design strategies. A new design process has been created, developed, and implemented to increase design process efficiency and creativity. This thesis additionally presents a structured method for defining and evaluating multiple objectives. Objective measures are defined as maximized visual comfort and preferred lighting conditions. The thesis introduces a new daylight glare index (DGln). Further, a study has been conducted comparing subjective glare response in an office space with the DGln. Its correlation yields very promising results. Moreover, this research investigates several design problems, GA parameters, and processes for improving design results and efficiency. The most important aspect of GA and its application is the use of computation not as an analytical tool but rather as a vehicle to stimulate learning in the design process. Finally, ideas are presented for future work, based on the potential suggested by our findings. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Architecture, 2001.; Includes bibliographical references (p. 145-147).; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.