VTechWorks Repository :: Browsing by Author "Reichard, Georg"

Browsing by Author "Reichard, Georg"

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Analysis and Management of UAV-Captured Images towards Automation of Building Facade Inspections
Chen, Kaiwen (Virginia Tech, 2020-08-27)
Building facades, serving mainly to protect occupants and structural components from natural forces, require periodic inspections for the detection and assessment of building façade anomalies. Over the past years, a growing trend of utilizing camera-equipped drones for periodical building facade inspection has emerged. Building façade anomalies, such as cracks and erosion, can be detected through analyzing drone-captured video, photographs, and infrared images. Such anomalies are known to have an impact on various building performance aspects, e.g., thermal, energy, moisture control issues. Current research efforts mainly focus on the design of drone flight schema for building inspection, 3D building model reconstruction through drone-captured images, and the detection of specific façade anomalies with these images. However, there are several research gaps impeding the improvement of automation level during the processes of building façade inspection with UAV (Unmanned Aerial Vehicle). These gaps are (1) lack effective ways to store multi-type data captured by drones with the connection to the spatial information of building facades, (2) lack high-performance tools for UAV-image analysis for the automated detection of building façade anomalies, and (3) lack a comprehensive management (i.e., storage, retrieval, analysis, and display) of large amounts and multi-media information for cyclic façade inspection. When seeking inspirations from nature, the process of drone-based facade inspection can be compared with caching birds' foraging food through spatial memory, visual sensing, and remarkable memories. This dissertation aims at investigating ways to improve the management of UAV-captured data and the automation level of drone-based façade anomaly inspection with inspirations from caching birds' foraging behavior. Firstly, a 2D spatial model of building façades was created in the geographic information system (GIS) for the registration and storage of UAV-images to assign façade spatial information to each image. Secondly, computational methods like computer vision and deep learning neural networks were applied to develop algorithms for automated extraction of visual features of façade anomalies within UAV-captured images. Thirdly, a GIS-based database was designed for the comprehensive management of heterogeneous inspection data, such as the spatial, multi-spectral, and temporal data. This research will improve the automation level of storage, retrieval, analysis, and documentation of drone-captured images to support façade inspection during a building's service lifecycle. It has promising potential for supporting the decision-making of early-intervention or maintenance strategies to prevent façade failures and improve building performance.
Analytical Framework to Study Energy Efficiency Policy Portfolios across Countries/States
Bhattacharjee, Suchismita (Virginia Tech, 2010-07-22)
Energy conservation and implementation of effective energy efficiency policies have become imperative to curbing the escalating consumption of energy. The imbalance in the supply and demand of a country's energy has increased the importance of implementing energy efficiency policies. Proper replication of strategic energy efficiency policies that are known to be successful in one country, along with development of new approaches, can be helpful in developing the energy policy portfolio of another country. Some OECD (Organization of Economic Cooperation and Development) countries like Denmark, Finland, France, Germany, Italy, the United Kingdom and the United States have benefited from their energy policies during the most recent energy crisis. The motivation of this research is to provide a tool for developing countries, which are still in the stage of formulating their energy efficiency policies, to compare energy efficiency policy portfolios across countries. These countries can improve their energy efficiency policy portfolios based on lessons learned from the developed countries. The research develops a framework to compare energy efficiency policy portfolios across countries / states. Although this framework can be adopted for any type of energy policy, targeting any sector with few modifications, the current focus is on policies that target the residential building sector to reduce energy consumption. The research begins with identification of the functional domains that influence human behavior–people, economy, environment and technology–followed by identification of the factors affecting household energy consumption. It uses the four functional domains as the evaluation framework's four axes. The various factors affecting household energy consumption are positioned in the framework based on association with the functional domains. The energy efficiency policies implemented in a country are positioned in the same framework based on the pattern of diffusion of each type of policy. In addition, a prototype method is developed to identify the factors targeted by each energy efficiency policy implemented in a country. This evaluation method allows for a uniform assessment process of how energy efficiency policies target specific socio-economic factors that are known to affect energy consumption. The proposed framework will facilitate the work of policy makers and other decision makers with a powerful tool for evaluating and comparing their individual policies, or their complete portfolio of energy efficiency policies, to those from other states or countries, and to benefit from the lessons learned.
Barriers and Cognitive Biases in the Monitoring-Based Commissioning Process
Harris, Nora Elizabeth (Virginia Tech, 2017-12-08)
Many buildings underperform leading to up to 20% energy waste. Case studies on monitoring-based commissioning (MBCx) have shown that using energy management and information systems (EMIS) for continuous energy monitoring and analysis enables the identification of issues that cause energy waste and verifies energy conservation measures. However, MBCx is underutilized by organizations leading to an energy efficiency gap between the energy saving potential of technologies like EMIS and observed savings. This energy efficiency gap can be attributed to general barriers to MBCx and barriers caused specifically by cognitive bias in the decision-making process. Using qualitative data from over 40 organizations implementing and practicing MBCx, this manuscript provides a better understanding of these barriers. Chapter 1 synthesizes and codes the qualitative data to develop a framework of variables acting as barriers and enablers to MBCx. The framework highlights commonly experienced barriers like data configuration, and also variables with conflicting results like payback/return on investment, which was experienced as a barrier to some organizations and enabler to others. Chapter 2 examines the barriers to MBCx through a behavioral decision science lens and finds evidence of cognitive biases, specifically, risk aversion, social norms, choice overload, status quo bias, information overload, professional bias, and temporal discounting. The success of choice architecture in other energy efficiency decisions is used to offer suggestions for ways to overcome these cognitive biases. This manuscript can be used by practitioners to better understand potential barriers to MBCx and by researchers to prioritize gaps and find methods to overcome the barriers to MBCx.
A BIM-based Interoperability Platform in Support of Building Operation and Energy Management
Xiong, Yunjie (Virginia Tech, 2020-03-18)
Building energy efficiency is progressively becoming a crucial topic in the architecture, engineering, and construction (AEC) sector. Energy management tools have been developed to promise appropriate energy savings. Building energy simulation (BES) is a tool mainly used to analyze and compare the energy consumption of various design/operation scenarios, while building automation systems (BAS) works as another energy management tool to monitor, measure and collect operational data, all in an effort to optimize energy consumption. By integrating the energy simulated data and actual operational data, the accuracy of a building energy model can be increased while the calibrated energy model can be applied as a benchmark for guiding the operational strategies. This research predicted that building information modeling (BIM) would link BES and BAS by acting as a visual model and a database throughout the lifecycle of a building. The intent of the research was to use BIM to document energy-related information and to allow its exchange between BES and BAS. Thus, the energy-related data exchange process would be simplified, and the productive efficiency of facility management processes would increase. A systematic literature review has been conducted in investigating the most popular used data formats and data exchange methods for the integration of BIM/BES and BAS, the results showed the industry foundation classes (IFC) was the most common choice for BIM tools mainly and database is a key solution for managing huge actual operational datasets, which was a reference for the next step in research. Then a BIM-based framework was proposed to supporting the data exchange process among BIM/BES/BAS. 4 modules including BIM Module, Operational Data Module, Energy Simulation Module and Analysis and Visualization Module with an interface were designed in the framework to document energy-related information and to allow its exchange between BES and BAS. A prototype of the framework was developed as a platform and a case study of an entire office suite was conducted using the platform to validate this framework. The results showed that the proposed framework enables automated or semi-automated multiple-model development and data analytics processes. In addition, the research explored how BIM can enhance the application of energy modeling during building operation processes as a means to improve overall energy performance and facility management productivity.
BIM-Based Turnover Documentation and Information System for Facility Management
Wang, Zhulin (Virginia Tech, 2019-08-30)
Facility management (FM) is a profession that deals with diverse types of information and requires multiple specific types of knowledge and skills. The technology of facility information management develops slowly, compared to the fast-changing building and construction technologies. With its popularity in facility design and construction, Building Information Modeling (BIM) is promising to reform the information and communication needs of facility managers. Yet there are still a lot of untapped potentials in using BIM during a facility's post-construction phases. The purpose of this study is to develop insights on the possible ways to improve facility information management with BIM from the real world examples and from literature. To start with, two case studies are conducted to get a better understanding of the current practice of facility information management. One is on the dynamic flow of information from the owner's perspective. The other is on the delivery of facility information to the owner from the contractor's perspective. The two case studies provide a close and holistic look at the real world of FM, which facilitates the interpretation of literature in the next stage. A comprehensive literature overview is conducted on the application of BIM in FM. The overview covers the benefits and obstacles of BIM application, various types of FM information, and technologies that enable more functions to manage FM information.
Computational Modeling of Glass Curtain Wall Systems to Support Fragility Curve Development
Gil, Edward Matthew (Virginia Tech, 2019-09-25)
With the increased push towards performance-based engineering (PBE) design, there is a need to understand and design more resilient building envelopes when subjected to natural hazards. Since architectural glass curtain walls (CW) have become a popular façade type, it is important to understand how these CW systems behave under extreme loading, including the relationship between damage states and loading conditions. This study subjects 3D computational models of glass CW systems to in- and out-of-plane loading simulations, which can represent the effects of earthquake or hurricane events. The analytical results obtained were used to support fragility curve development which could aid in multi-hazard PBE design of CWs. A 3D finite element (FE) model of a single panel CW unit was generated including explicit modeling of the CW components and component interactions such as aluminum-to-rubber constraints, rubber-to-glass and glass-to-frame contact interactions, and semi-rigid transom-mullion connections. In lieu of modeling the screws, an equivalent clamping load was applied with magnitude based on small-scale experimental test results corresponding to the required screw torque. This FE modeling approach was validated against both an in-plane racking displacement test and out-of-plane wind pressure test from the literature to show the model could capture in-plane and out-of-plane behavior effectively. Different configurations of a one story, multi-panel CW model were generated and subjected to in- and out-of-plane simulations to understand CW behavior at a scale that is hard to test experimentally. The structural damage states the FE model could analyze included: 1) initial glass-to-frame contact; 2) glass/frame breach; 3) initial glass cracking; 4) steel anchor yielding; and 5) aluminum mullion yielding. These were linked to other non-structural damage states related to the CW's moisture, air, and thermal performance. Analytical results were converted into demand parameters corresponding to damage states using an established derivation method within the FEMA P-58 seismic fragility guidelines. Fragility curves were then generated and compared to the single panel fragility curves derived experimentally within the FEMA P-58 study. The fragility curves within the seismic guidelines were determined to be more conservative since they are based on single panel CWs. These fragility curves do not consider: the effects of multiple glass panels with varying aspect ratios; the possible component interactions/responses that may affect the extent of damages; and the continuity of the CW framing members across multiple panels. Finally, a fragility dispersion study was completed to observe the effects of implementing the Derivation method or the Actual Demand Data method prescribed by FEMA P-58, which differ on how they account for different levels of uncertainty and dispersion in the fragility curves based on analytical results. It was concluded that an alternative fragility parameter derivation method should be implemented for fragility curves based on analytical models, since this may affect how conservative the analytically based fragility curves become at a certain probability of failure level.
A Decision-Support Framework for the Design and Application of Radiant Cooling Systems
Ma'bdeh, Shouib Nouh (Virginia Tech, 2011-10-31)
Creating a sense of place through a comfortable indoor condition is a goal of the architectural design process. Thermal comfort is an important component of this condition. To achieve thermally comfortable environments mechanical systems such as Radiant Cooling (RC) could be used. RC systems have potential benefit of lower energy consumption when compared to other common cooling, ventilating and air-conditioning systems. Decisions related to the use of mechanical systems such as these should be considered in the early stages of design to maximize the building performance through systems integration and minimize redesign as part of the design process. RC systems have several special demands and related variables. Architects, HVAC system engineers, and decision-makers have to understand these issues and variables and their impact on the other building performance mandates. Through this understanding, these professionals can better evaluate tradeoffs to reach the desired solution of the design problem. Unfortunately, in the United States few architects and engineers have experience with RC systems which in turn limits the application of these systems. Through systematic literature review, a series of case studies, and interviews with experienced professionals, this research captures and structures knowledge related to how decisions are made concerning RC systems. Through this knowledge capturing procedure, the relevant design performance mandates, barriers and constraints, and potential advantages and benefits of radiant cooling systems are determined and mapped to a decision-support framework. This framework is graphically presented which may later be translated to a decision-support software package which could then be developed as a radiant cooling system design assistance tool for architects and HVAC engineers.
Developing Prefabricated, Light-weight CLT Exterior Wall Panels for Mid-rise Buildings
Sharifniay Dizboni, Houri (Virginia Tech, 2024-06-10)
The building construction industry has seen the emergence of Cross Laminated Timber (CLT) as a renewable replacement for structural application of steel, concrete, and masonry. However, CLT has not been researched extensively as a nonstructural component of the building envelope/facade. In the presented research, the application of CLT is introduced in the form of lightweight CLT (CLT-L) panels and presents a framework to evaluate the opportunities and application of CLT-L panels as an alternative construction method for non-load-bearing exterior wall systems. Since exterior walls as part of the enclosure system have a significant role in energy consumption and human comfort level, the research evaluates application opportunities of the CLT panels for US climates, by conducting a life cycle environmental analysis, and a thermal evaluation of CLT-L systems for Phoenix, Arizona, and Minneapolis, Minnesota. The life cycle analysis was conducted to assess the environmental impact of a typical CLT wall system as compared to three conventional panelized wall systems. The results of the analysis have shown that CLT wall systems exhibit the lowest cumulative life cycle environmental impact indicators, including acidification potential, fossil fuel consumption, global warming potential, and human health particulate when compared to other wall systems. These results suggest that CLT wall systems could be a viable alternative to conventional panelized exterior wall systems from an environmental impact perspective. In the next step, a parametric study was conducted to determine the optimal configuration of a CLT-L wall system for enhanced thermal performance. This was achieved through dynamic thermal simulations by employing the conduction transfer algorithm and analyzing various thicknesses and locations of the thermal insulation layer. Through analysis of the annual thermal transmission load and decrement factor, the optimum insulation thicknesses for CLT wall systems in two climate regions were determined. The results showed that the exterior insulation location yields better thermal efficiency. The results of this phase were employed in the development of the CLT wall system model and conduction of a comparative parametric study on the thermal mass behavior of CLT and CMU wall systems via finite difference algorithm. One significant outcome of the simulation data analysis was the heat transfer dynamics within the CLT and CMU wall system when exterior insulation is applied. The analysis revealed that in the presence of exterior insulation, the CLT layer continues to be the primary contributor to the reduced thermal transmission of the wall. However, in the CMU mass wall configuration, the insulation layer assumes a dominant role in the reduced thermal transmission of the wall. The findings of this research present CLT as a potential environmentally efficient envelope alternative for framed buildings and provide insights into the thermal performance of CLT wall systems, which can lead to the opening of a new market for CLT panel application in the U.S.
Development of a Model for Predicting the Transmission of Sonic Booms into Buildings at Low Frequency
Remillieux, Marcel C. (Virginia Tech, 2010-05-03)
Recent progresses by the aircraft industry in the development of a quieter supersonic transport have opened the possibility of overland supersonic flights, which are currently banned by aviation authorities in most countries. For the ban to be lifted, the sonic booms the aircraft generate at supersonic speed must be acceptable from a human-perception point of view, in particular inside buildings. The problem of the transmission of sonic booms inside buildings can be divided in several aspects such as the external pressure loading, structure vibration, and interior acoustic response. Past investigations on this problem have tackled all these aspects but were limited to simple structures and often did not account for the coupled fluid-structure interaction. A more comprehensive work that includes all the effects of sonic booms to ultimately predict the noise exposure inside realistic building structures, e.g. residential houses, has never been reported. Thus far, these effects could only be investigated experimentally, e.g. flight tests. In this research, a numerical model and a computer code are developed within the above context to predict the vibro-acoustic response of simplified building structures exposed to sonic booms, at low frequency. The model is applicable to structures with multiple rectangular cavities, isolated or interconnected with openings. The response of the fluid-structure system, including their fully coupled interaction, is computed in the time domain using a modal-decomposition approach for both the structural and acoustic systems. In the dynamic equations, the structural displacement is expressed in terms of summations over the "in vacuo" normal modes of vibration. The interior pressure is expressed in terms of summations over the acoustic modes of the rooms with perfectly reflecting surfaces (hard walls). This approach is simple to implement and computationally efficient at low frequency, when the modal density is relatively low. The numerical model is designed specifically for this application and includes several novel formulations. Firstly, a new shell finite-element is derived to model the structural components typically used in building construction that have orthotropic characteristics such as plaster-wood walls, floors, and siding panels. The constitutive matrix for these types of components is formulated using simple analytical expressions based on the orthotropic constants of an equivalent orthotropic plate. This approach is computationally efficient since there is no need to model all the individual subcomponents of the assembly (studs, sheathing, etc.) and their interconnections. Secondly, a dedicated finite-element module is developed that implements the new shell element for orthotropic components as well as a conventional shell element for isotropic components, e.g. window panels and doors. The finite element module computes the "in vacuo" structural modes of vibration. The modes and external pressure distribution are then used to compute modal loads. This dedicated finite-element module has the main advantage of overcoming the need, and subsequent complications, for using a large commercial finite-element program. Lastly, a novel formulation is developed for the fully coupled fluid-structure model to handle room openings and compute the acoustic response of interconnected rooms. The formulation is based on the Helmholtz resonator approach and is applicable to the very low frequency-range, when the acoustic wavelength is much larger than the opening dimensions. Experimental validation of the numerical model and computer code is presented for three test cases of increasing complexity. The first test structure consists of a single plaster-wood wall backed by a rigid rectangular enclosure. The structure is excited by sonic booms generated with a speaker. The second test structure is a single room made of plaster-wood walls with two double-panel windows and a door. The third test structure consists of the first room to which a second room with a large window assembly was added. Several door configurations of the structure are tested to validate the formulation for room openings. This latter case is the most realistic one as it involves the interaction of several structural components with several interior cavities. For the last two test cases, sonic booms with realistic durations and amplitudes were generated using an explosive technique. Numerical predictions are compared to the experimental data for the three test cases and show a good overall agreement. Finally, results from a parametric study are presented for the case of the single wall backed by a rigid enclosure. The effects of sonic-boom shape, e.g. rise time and duration, and effects of the structure geometry on the fluid-structure response to sonic booms are investigated.
The Development of Models to Identify Relationships Between First Costs of Green Building Strategies and Technologies and Life Cycle Costs for Public Green Facilities
Ahn, Yong Han (Virginia Tech, 2010-02-18)
Public buildings and other public facilities are essential for the functioning and quality of life in modern societies, but they also frequently have a significant negative impact on the natural environment. Public agencies, with their large portfolios of facilities, have faced considerable challenges in recent years in minimizing their negative environmental impacts and energy consumption and coping with shortages of financial capital to invest in new facilities and operate and maintain existing ones, while still meeting their mission goals. These range from the need to provide a quality workplace for their staff to providing a public service and long term benefits to the public. The concept of green building has emerged as a set of objectives and practices designed to reduce negative environment impacts and other challenges while enhancing the functionality of built facilities. However, the prevailing belief related to implementing green building is that incorporating Green Building Strategies and Technologies (GBSTs) increases the initial cost of constructing a facility while potentially reducing its life cycle costs. Thus, this research deals with optimizing the design of individual facilities to balance the initial cost investment for GBSTs versus their potential Life Cycle Cost (LCC) savings without the need to conduct detailed life cycle cost analysis during the early capital planning and budget phases in public sector projects. The purpose of this study is to develop an approach for modeling the general relationship between investments in initial costs versus savings in LCCs involved in implementing green building strategies in public capital projects. To address the research question, this study developed multiple regression models to identify the relationships between GBSTs and their initial cost premiums, operating costs, and LCCs. The multiple regression models include dummy variables because this is a convenient way of applying a single regression equation to represent several nominal variables, which here consist of initial, operating, maintenance, and repair and replacement costs, and ordinal variables, which in this case are the GBST alternatives considered. These new regression models can be used to identify the relationship between GBST alternatives, initial cost premiums, annual operating costs and LCC in the earliest stage of a project, when public agencies are at the capital planning and budgeting stages of facility development, without necessarily needing to know the precise details of design and implementation for a particular building. In addition, this study also proposes and tests a method to generate all the necessary cost data based on building performance models and industry accepted standard cost data. This statistical approach can easily be extended to accommodate additional GBSTs that were not included in this study to identify the relationship between their initial cost premium and their potential LCC saving at the earliest stage of facility development. In addition, this approach will be a useful tool for other institutional facility owners who manage large facility portfolios with significant annual facility investments and over time should help them minimize the environmental impacts caused by their facilities.
An Effort to Refine Home Energy Assessment Methods in Support of Retrofit Decision Making
Ladipo, Oluwateniola Eniola (Virginia Tech, 2013-06-05)
This research evaluates current home energy assessment tools and practices and investigates their applicability in terms of relevance supporting retrofit decision making in Southwest Virginia. Home energy assessments and audits are comprised of many different tools, strategies, and practices all with the same goal, to achieve accuracy in assessing performance as well as confidence in achieving energy savings from retrofit recommendations. Differing opinions, training, and standards in energy assessments have led to a reduced confidence and reliance on energy assessments, which can ultimately lead to poor retrofit decisions and undesired outcomes. This research undertook an investigation of current tools and practices as well as modeling studies to reveal insights into strengths and weaknesses, and to refine home energy assessments. The goal was to identify opportunities to increase confidence for stakeholders by analyzing energy assessments in terms of what strategies are most suitable to increase the accuracy of capturing different energy influence parameters, as well as to provide a basis for future research and development in this subject area.
An Energy Diffusion Model for Interior Acoustics with Structural Coupling Using the Laplace Transform Boundary Element Solution
Corcoran, Joseph Michael (Virginia Tech, 2013-06-13)
Knowledge of the indoor propagation of sound has many important applications including acoustic prediction in homes, office buildings, stores, and schools, and the design of concert halls, auditoriums, classrooms, and factories. At low frequencies, interior acoustics are analyzed with the wave equation, but significant computational expense imposes an upper frequency limit. Thus, energy methods are often sought for high frequency analysis. However, conventional energy methods are significantly limited by vast simplifications or computational costs. Therefore, new improvements are still being sought. The basis of this dissertation is a recently developed mathematical model for interior acoustics known as the acoustic diffusion model. The model extends statistical methods in high frequency acoustics to predict the spatial distribution of acoustic energy in the volume over time as a diffusion process. Previously, solutions to the acoustic diffusion model have been limited to one dimensional (1-D) analytical solutions and to the use of the finite element method (FEM). This dissertation focuses on a new, efficient method for solving the acoustic diffusion model based on a boundary element method (BEM) solution using the Laplace transform. First, a Laplace domain solution to the diffusion model is obtained using the BEM. Then, a numerical inverse Laplace transform is used to efficiently compute the time domain response. The diffusion boundary element-Laplace transform solution (BE-LTS) is validated through comparisons with Sabine theory, ray tracing, and a diffusion FEM solution. All methods demonstrate excellent agreement for three increasingly complex acoustic volumes and the computational efficiency of the BE-LTS is exposed. Structural coupling is then incorporated in the diffusion BE-LTS using two methods. First, a simple transmission coefficient separating two acoustic volumes is implemented. Second, a structural power flow model represents the coupling partition separating acoustic volumes. The validation of these methods is successfully performed in an example through comparisons with statistical theory, a diffusion FEM solution, ray tracing, and experimental data. Finally, the diffusion model and the BE-LTS are shown to possess capabilities beyond that of room acoustics. The acoustic transmission through a heat exchanger, acoustic foam, and mufflers is successfully modeled using the diffusion BE-LTS and compared to experimental data.
Energy Efficiency Opportunities for Tobacco Curing Barns
Reichard, Georg; Pearce, Annie R. (Virginia Tech. Myers Lawson School of Construction, 2013)
This project report discusses a theoretical assessment model for investigating the savings potential of retrofit scenarios for curing barns. The authors evaluated the most practical and also typical retrofit scenarios, such as envelope improvements and the installation of an automated control systems. In terms of their anticipated impact on energy savings the different opportunities ranged from around 6% for added control strategies to around 12% for typical standard envelope improvements. A total upper limit of savings around 25% has been established, if more aggressive envelope improvements are paired with automated control systems. While the commonly known retrofit scenarios tackle all consumption domains other than the dehumidification/ventilation domain, it became apparent that the most promising savings lay in recovering some of the ventilation losses that are a result of controlling for the relative humidity in the curing compartment of the barn.
Energy-in-Form
Hamm, Teresa Dolores (Virginia Tech, 2019-02-11)
This thesis is a study of architectural form in relation to energy. Energy performance is rooted in form. Overall performance in the practice of architecture includes necessarily consumption as a form constraint. The term energy in this body of work relates to the social circumstance that the current state of the environment imposes on all facets of life, including how our buildings contribute to the anthropogenic warming of the earth's atmosphere. Humans are consumptive and so our buildings, a product of our work, are inherently consumptive as well. The challenge is to design environments that stimulate responsible actions by considering energy consumption throughout the design process. This thesis proposes that an architecture which responds with significance explores the energy-in-form to make a contribution to the current condition in which we live. On an abstract level, formal elements of negation and the condition of boundary are explored in relation to energy. On a more factual level, the impact of energy on site orientation, shading, and in-between zones are tested. Form in the study of the proportions of the Maison Carrée is expressed in the process of making concrete objects and the regulating geometry and formal conditions of the final Cornerstore building design.
An Evaluation Approach of Socio Economic Factors Affecting Household Energy Consumption
Bhattacharjee, Suchismita; Reichard, Georg (2011)
Residential energy consumption in the United States has been marked by a steady growth over the past decades, in spite of the implementation of various energy efficiency policies. To frame effective energy policies for the residential sector it is important to understand the cause and impact of factors affecting residential energy consumption. A vast majority of earlier research has explored the role of individual human factors that are responsible for the increase of household energy usage, whereas, a few studies have discussed the effect of standard-of-living and income on overall household energy consumption. However, there is a dearth of literature and research on plausible ways to modify and manipulate factors that influence household energy consumption. This paper builds on previous research by the authors that identified a list of factors affecting residential energy consumption and grouped them under five major categories, i.e. demographics, consumer attitude, economic variables, climate, and technology. The here presented investigation analyzes the root causes for each of the identified consumption factors such as household size, dwelling characteristics, etc. through Cause & Effect diagrams. Finally, all energy efficiency control elements under each of the energy consumption factors are generated and sorted using the Affinity Diagram method. Our research shows how the identified control elements govern energy consumption factors to a great extent. Ultimately these control elements will assist policy makers in ameliorating and targeting the most critical factors that will help to curb the increasing household energy consumption in the United States.
Experimental Characterization and Analysis of Simple Residential Structures Subjected to Simulated Sonic Booms
Haac, Thomas Ryan (Virginia Tech, 2010-05-03)
Commercial aircraft are subject to noise regulations imposed by the Federal Aviation Administration. Currently, the FAA limits overland flight of supersonic airplanes due to the negative effect of the sonic boom on communities. The annoyance produced by the impulsive signature of sonic booms, particularly indoors, cannot exceed that of the broadband, low-overpressure noise produced by subsonic airplanes for the restriction to be lifted. Therefore, the ability to understand and accurately reproduce the acoustic response of a sonic boom is important for psychoacoustic classification of their tolerability within residences. This thesis presents and interprets results of the propagation and transmission of simulated sonic booms incident on wood-framed structures. The testing environment, sonic boom simulation method, and associated instrumentation are described. The effects of the traveling blast on the structure are investigated through pressure loading and structural response measurements. The ensuing interior acoustic responses for several different configurations are presented, including the effects of room cavity interaction and exposure of the room cavities to the traveling wave through an open door. Calculated transfer functions between the interior acoustic response and the free-field incident wave are computed to assess the extent to which wood-framed buildings transmit energy to their cavities. In all cases tested, significant transmission of the sonic boom's low frequency content into the structures was apparent through direct apertures and the excitation of structural components. The data show that sonic booms provide significant excitation of structural and acoustic modes that drives the interior acoustic response in residential structures.
Fifty Shades of Building Science
Reichard, Georg (Virginia Tech, 2020)
The role of building science education examined in the context of past DOE student competitions. A presentation part of panel discussion at the 5th RBDCC. This paper presents findings from a meta analysis of DOE Student Competition Guidelines and competition winners in terms of Building Science keywords and requirements. The Race to Zero was an annual competition from 2014-2018, which got merged into the broader DOE Solar Decathlon competition framework in 2019. In its outset, this design competition was created to engage and challenge students and faculty to apply sound building science principles to create cost-effective, market-ready designs. While the standard, quality, and extent of winning submission has dramatically increased over the years, some concerns have emerged that the teams have lost sight of the original goals and that building science criteria may not have been met by a majority of submissions anymore. This paper will examine and synthesize past competition guidelines as they relate to building science topics and assess available project submissions of winning teams on those criteria only. The goal of this paper is to facilitate a discussion on how building science criteria could be sharpened and possibly expanded in future competition guidelines.
A Framework for Simplified Residential Energy Consumption Assessment towards Developing Performance Prediction Models for Retrofit Decision-Making
Durak, Tolga (Virginia Tech, 2011-11-07)
This research proposes to simplify the energy consumption assessment for residential homes while building the foundation towards the development of prediction tools that can achieve a credible level of accuracy for confident decision making. The energy consumption assessment is based on simplified energy consumption models. The energy consumption analysis uses a reduced number of energy model equations utilizing a critical, limited set of parameters. The results of the analysis are used to develop the minimum set of consumption influence parameters with predicted effects for each energy consumption domain. During this research study, multiple modeling approaches and occupancy scenarios were utilized according to climate conditions in Blacksburg, Virginia. As a part of the analysis process, a parameter study was conducted to: develop a comprehensive set of energy consumption influence parameters, identify the inter-relationships among parameters, determine the impact of energy consumption influence parameters in energy consumption models, and classify energy consumption influence parameters under identified energy consumption domains. Based on the results of the parameter study, a minimum set of parameters and energy consumption influence matrices were developed. This research suggests the minimum set of parameters with predicted effects to be used during the development of the simplified baseline energy consumption model.
A Framework to Support the Development of Manually Adjustable Light Shelf Technologies
Javed, Shamim (Virginia Tech, 2014-06-30)
Active daylight harvesting technologies that are currently available in the market have often suffered from wide-spread market acceptability due to their high cost and imperfect performance. Passive systems, though simple and affordable, typically cannot harvest higher potentials of daylight, which is dynamic over days, months, and seasons, due to their static nature. There is a research and market gap that calls for investigation towards the development of low-tech, manually adjustable, high-performance daylighting mechanisms to be used as an alternative to active daylighting solutions, which are often controlled by building automation systems. This research proposes a framework to support the development of daylight harvesting mechanisms, which will allow for low-tech yet temporary adjustable systems, merging some of the advantages of active systems with passive ones. The hybrid of the above two categories will be a manually adjustable light harvesting device that will allow for quick adjustment through mechanical means to few predefined positions. These positions will be customized to each location to achieve optimum daylight harvesting. The resulting device will allow for flexible adjustment to daily and seasonal variations of the sun's path, while retaining a level of simplicity and elegance towards low-cost installation and operation. Significant effort was made in the initial phase of this research to use experimental studies as the primary method of investigation. However, given the nature of daylight and practical constraints in the field, the experimental method was found to be not productive enough for extent of this research. As a result, simulation studies were ultimately used to generate the necessary data for the development of this framework. For the simulation phase 'DIVA4Rhino,' a climate-based daylighting software and 'Grasshopper,' a graphical programming tool for Rhino, was used to first construct a parametric simulation loop. Next, a reduced set of parameters for a manually adjustable light shelf system were tested for daylight performance, as a 'proof of concept'. Finally, based on the previous two steps, a framework to help the development of manually adjustable light shelf systems has been defined. This research shows that light shelves, even when kept fixed at a single optimum configuration for the whole year, can increase interior daylight performance in most locations and orientations. It also shows that indoor daylight harvesting can be further enhanced if the light shelf is manually adjusted on a seasonal basis. Amongst the variations tested, rotational adjustability has been found to contribute most to the increase in performance. Segmented adjustability, e.g. where the inner and outer sections of a light shelf are manipulated separately, was found to extend performance of light shelves even further though not by significant amounts.
Human-Interactions with Robotic Cyber-Physical Systems (CPS) for Facilitating Construction Progress Monitoring
Halder, Srijeet (Virginia Tech, 2023-08-23)
Progress monitoring in construction involves a set of inspection tasks with repetitive in-person observations on the site. The current manual inspection process is time-consuming, inefficient, inconsistent, and has many safety risks to project inspectors. Cyber-Physical Systems (CPS) are networks of integrated physical and cyber components, such as robots, sensors, actuators, cloud computing, artificial intelligence, and the building itself. Introducing CPS for construction progress monitoring can reduce risks involved in the process, improve efficiency, and enable remote progress monitoring. A robotic CPS uses a robot as the core component of the CPS. But human interaction with technology plays an important role in the successful implementation of any technology. This research studied the human-centered design of a CPS from a human-computer interaction perspective for facilitating construction progress monitoring that puts the needs and abilities of humans at the center of the development process. User experience and interactions play an important role in human-centered design. This study first develops a CPS framework to autonomously collect visual data and facilitate remote construction progress monitoring. The two types of interactions occur between the human and the CPS – the human provides input for the CPS to collect data referred to as mission planning, and CPS provides visual data to enable the human to perform progress analysis. The interaction may occur through different modalities, such as visual, tactile, auditory, and immersive. The goal of this research is to understand the role of human interactions with CPS for construction progress monitoring. The study answers five research questions – a) What robotic CPS framework can be applied in construction progress monitoring? b) To what extent is the proposed CPS framework acceptable as an alternative to traditional construction progress monitoring? c) How can natural interaction modalities like hand gestures and voice commands be used as human-CPS interaction modalities for the proposed CPS? d) How does the human interaction modality between the proposed CPS and its user affect the usability of the proposed CPS? e) How does the human interaction modality between CPS and its user affect the performance of the proposed CPS?. To answer the research questions, a mixed-method-based methodology is used in this study. First, a systematic literature review is performed on the use of robots in inspection and monitoring of the built environment. Second, a CPS framework for remote progress monitoring is developed and evaluated in lab conditions. Third, a set of industry experts experienced with construction progress monitoring are interviewed to measure their acceptance of the developed CPS and to collect feedback for the evaluation of the CPS. Fourth, two methodologies are developed to use hand gesture and voice command recognition for human-CPS interaction in progress monitoring. Fifth, the usability and performance of the CPS are measured for identified interaction modalities through a human subject study. The human subjects are also interviewed post-experiment to identify the challenges they faced in their interactions with the CPS. The study makes the following contributions to the body of knowledge – a) key research areas and gaps were identified for robots in inspection and monitoring of the built environment, b) a fundamental framework for a robotic CPS was developed to automate reality capture and visualization using quadruped robots to facilitate remote construction progress monitoring, c) factors affecting the acceptance of the proposed robotic CPS for construction progress monitoring were identified by interviewing construction experts, d) two methodologies for using hand gestures and voice commands were developed for human-CPS interaction in construction progress monitoring, e) the effect of human interaction modalities on the usability and performance of the proposed CPS was assessed in construction progress monitoring through user studies, f) factors affecting the usability and performance of the proposed CPS with different interaction modalities were identified by conducting semi-structured interviews with users.

Browsing by Author "Reichard, Georg"

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