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Title: A CONCEPTUAL ENERGY DESIGN FOR O’HARE INTERNATIONAL AIRPORT USING WIND AND BUILDING INTEGRATED PHOTOVOLTAIC SYSTEMS
Creator: Gomez Soriano, Maria
Date: 2014, 2014-12
Description: Commercial buildings account for approximately 18% of the total energy use in the United States, although only 7% of this consumption is...
Show moreCommercial buildings account for approximately 18% of the total energy use in the United States, although only 7% of this consumption is currently supplied by renewable energy sources, including hydropower, biomass, geothermal, wind, and solar heat and photovoltaics. This is a low percentage and it is imperative to explore potentials for using a combination of renewable energy systems to increase this percentage, particularly for large establishments with large land areas and existing facilities that can support large amounts of renewable energy technologies, such as airports. O’Hare International Airport (ORD), located in Chicago (Illinois), has been selected for this research, with the main purpose of supplying the maximum possible amount of the airport energy demand by a proposed wind and solar hybrid system. The first part of this research includes a wind energy system design performed using wind speed data at ORD locations and determining a suitable number and type of turbines loacted within the airport premises. Special considerations are made for for height, turbine locations, and prevailing wind directions. The second part of the study involves design of solar photovoltaic panel arrays both for existing terminals as well as for a proposed new terminal. The design of the arrays includes considerations for optimal energy production with varying installation angles as well as the number of sunny days useful for sun energy harvesting. Finally, the total electricity output from the hybrid system is estimated and compared with the total and monthly electricity demand at ORD. Results show that a considerable percentage of the electricity demand at ORD can be obtained through the wind and solar hybrid system. Specifically, if the airport authority decides on a new terminal, the integration of PV panels with the new terminal structure can be optimized such that the pecentage of total electricty demand at ORD could be met by more than 50% on-site renewable energy sources. An analysis of potential return in investment reveals that economically such a design is viable and can result in sizeable annual savings over a 20-year investment period.
M.S. in Civil, Architectural and Environmental Engineering, December 2014
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Title: MOTIVATING CONSTRUCTION PROJECT MANAGERS AND ASSESSING THEIR HUMAN VALUES: THE VALUE/MOTIVATION LINKAGE
Creator: Wang, Di
Date: 2011-11-29, 2011-12
Description: Worker productivity and performance are critical to companies. Workers’ motivation has typically been investigated based on the well-known...
Show moreWorker productivity and performance are critical to companies. Workers’ motivation has typically been investigated based on the well-known hierarchical need theory of Maslow (1943), the two-factor need theory of Herzberg (1968), the need theory of Alderfer (1972), and the expectancy theory of Vroom (1964). Construction managers occupy middle management positions and are as important as regular workers to the success of a project. Therefore, construction managers’ motivation should also be investigated. This study investigates the factors that motivate construction managers, and the human value of construction managers. The motivators are extracted from previous studies and the human values from Rokeach’s (1973) work. The relationship between construction managers’ human values and the motivators is explored, which previous studies never attempted before is implemented in this study. 101 out of 1000 construction managers participated in a survey asking them to rate the importance of 20 motivators and 18 human values. Factor analysis was used to reduce the 20 motivators to six factors. Inter-correlation analysis was conducted and the 18 human values were reduced to 9. Multiple regression analysis was conducted between the 9 human values against each one of the motivation factors. However, the R2 were low. Therefore artificial neural networks (ANN) were used to analyze the relationship. The ANN model was able to predict the relationship between human values and each of the six motivational factors with 75% accuracy. If higher executives are able to determine the human values of their construction managers, they should be able to motivate their construction managers by promoting the appropriate motivators.
M.S. in Civil Engineering, December 2011
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Title: MOBILITY IMPROVEMENT BENEFIT ANALYSIS OF SIGNAL TIMING OPTIMIZATION FOR URBAN STREET NETWORK
Creator: Zhang, Ji
Date: 2015, 2015-05
Description: The traffic congestion problem especially in urban areas is getting increasingly severe due to the ever-growing auto travel demand in the...
Show moreThe traffic congestion problem especially in urban areas is getting increasingly severe due to the ever-growing auto travel demand in the United States during the past few decades. In general, insufficient capacity can be solved by system expansion. However, expanding system is not feasible anymore because of the land scarcity in urban areas and its high cost. From this point of view, transportation operations that lead to the optimal system usage are more preferable thanks to their relatively low cost and remarkable consequences. Several performance indices were used in order to assess the effects of a given transportation operation. This study introduces a new method for evaluating the mobility performance of the transportation system before and after a transportation operation. And the mobility benefit is converted into monetary value. Further, a Life-Cycle Benefit Analysis is conducted to expand the evaluation process to the time dimension. An experimental study is performed to apply this method on the urban street network in Chicago downtown area that contains 917 intersections and 1675 roadway segments before and after a network-wide signal timing optimization treatment. Based on this application, the results indicate a few potential advantages and disadvantages of this system-wide signal timing optimization methodology.
M.S. in Civil Engineering, May 2015
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Title: FEM-BASED MULTIPHYSICS MODELING OF CONTAMINATION AND REMEDIATION OF VARIABLY SATURATED SOILS
Creator: Miao, Tao
Date: 2015, 2015-05
Description: With the increasing awareness of environmental protection, the soil contamination has been a major problem in this industrial world. This...
Show moreWith the increasing awareness of environmental protection, the soil contamination has been a major problem in this industrial world. This study aims to develop numerical tools to simulate the soil pollution process and evaluate the effectiveness and efficiency of remediation solutions. First of all, a mathematical model was built to describe the pollutants (chemical species) transport phenomenon in soil, especially under unsaturated states. The model is developed based on mass conversation principle and two mechanisms were taken into account, including natural diffusion and convective flow. In order to obtain the flow velocity in soil, a variety of material parameters for soil such as permeability and hydraulic conductivity should be determined. The Richard’s equation, commonly used in formulating soil-water characteristic curves, was adopted to study moisture movement in the variably saturated soils. The model was applied to predict multiple pollutant species transporting in clayey, silty and sandy soils. Second, as a new coming method, electrokinetic remediation has been proven an effective and sustainable solution to clean up contaminated soil. Resulting from the added external electrical field, electroosmosis and electromigration were generated, which can remove pollutant ions from the polluted soil domain. A second model was built to evaluate cleaning up efficiency of electrokinetic solution, and then implemented to simulate remediation of soil contaminated by nuclear waste. The last part of this study aims to focus on another remediation solution. Bioremediation is becoming an effective method for treating soils or geo-materials contaminated by organic pollutants. Bioremediation can be defined as introduction of bacteria or fungi to foster degradation and removal of pollutants. The development of the third model for determining the mobility and growth of bacterial microorganisms are presented. This model captures three major propagation mechanisms in unsaturated soils, including natural diffusion, bacterial growth and convective flow. By adding relationship between pollutant degradation rate and bacteria concentration, the fourth model was applied to study the bioremediation remediation of petroleum pollution. Finite element method was conducted to solve mathematical models, which are partial differential equations of high nonlinearity. Based on computational results from the fist model, concentrations of various pollutants for both inorganic and organic can be predicted at any interested time in different types of soils under various environmental conditions. The second and fourth models can be used as numerical tools, which greatly facilitate the designing and evaluation of cleaning efficiency and effectiveness of electrokinetic remediation and bioremediation schemes, respectively.
M.S. in Civil, Architectural and Environmental Engineering, May 2015
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Title: NUMERICAL ANALYSIS OF NON-DUCTILE BRACE FRAME WITH KNIFE PLATE DUE TO DYNAMIC LOADS
Creator: Keivan Esfahani, Arshia
Date: 2014, 2014-05
Description: In recent years, typical steel construction in regions of high seismic risk has shifted from moment-resisting frames to concentrically braced...
Show moreIn recent years, typical steel construction in regions of high seismic risk has shifted from moment-resisting frames to concentrically braced frames. As a result of the increased popularity of braced frames, the poor performance of some conventionally braced frames in past earthquakes, and the limited experimental data available on the inelastic response and the failure characteristics of braced-frame systems, a series of experimental and analytical investigations were initiated. Steel concentrically braced frames are common lateral force resisting systems in both new construction and existing buildings. However, the seismic behavior of braced frames designed prior to the adoption of capacity design principles in the 1980s is generally not well understood despite their widespread presence. These older braced frames, termed non-seismic concentrically braced frames (NCBFs) are the subject of a research project titled “NEESR: Collaborative Developments for Seismic Rehabilitation of Vulnerable Braced Frames” that seeks to evaluate NCBFs and determine retrofit strategies. In this project two tests were conducted. First Test examined a full scale two story NCBF in the inverted V configuration subjected to quasistatic cyclic load and this specimen contained a bottom story beam that is considered weak in capacity design. Second Test examined a post-earthquake repair scenario using the damaged NCBF-INV-1 frame in which the bottom story braces and gusset plates were removed and replaced with seismically compact braces with connection designed for in plane buckling. In this work, finite element models developed in Abaqus were validated using data collected from these tests. The outcomes of this research will be a greater understanding of seismic performance of NCBFs, the development of rehabilitation strategies for vulnerable NCBFs, and a robust technique for modeling NCBFs.
M.S. in Civil Engineering, May 2014
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Title: MOBILITY IMPROVEMENT BENEFIT ANALYSIS OF SIGNAL TIMING OPTIMIZATION FOR URBAN STREET NETWORK
Creator: Zhang, Ji
Date: 2015, 2015-05
Description: The traffic congestion problem especially in urban areas is getting increasingly severe due to the ever-growing auto travel demand in the...
Show moreThe traffic congestion problem especially in urban areas is getting increasingly severe due to the ever-growing auto travel demand in the United States during the past few decades. In general, insufficient capacity can be solved by system expansion. However, expanding system is not feasible anymore because of the land scarcity in urban areas and its high cost. From this point of view, transportation operations that lead to the optimal system usage are more preferable thanks to their relatively low cost and remarkable consequences. Several performance indices were used in order to assess the effects of a given transportation operation. This study introduces a new method for evaluating the mobility performance of the transportation system before and after a transportation operation. And the mobility benefit is converted into monetary value. Further, a Life-Cycle Benefit Analysis is conducted to expand the evaluation process to the time dimension. An experimental study is performed to apply this method on the urban street network in Chicago downtown area that contains 917 intersections and 1675 roadway segments before and after a network-wide signal timing optimization treatment. Based on this application, the results indicate a few potential advantages and disadvantages of this system-wide signal timing optimization methodology.
M.S. in Civil, Architectural and Environmental Engineering, May 2015
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Title: NUMERICAL ANALYSIS OF NON-DUCTILE BRACED FRAME DUE TO DYNAMIC LOADS
Creator: Keivan Esfahani, Ashkan
Date: 2014, 2014-05
Description: In recent years, typical steel construction in regions of high seismic risk has shifted from moment-resisting frames to concentrically braced...
Show moreIn recent years, typical steel construction in regions of high seismic risk has shifted from moment-resisting frames to concentrically braced frames. As a result of the increased popularity of braced frames, the poor performance of some conventionally braced frames in past earthquakes, and the limited experimental data available on the inelastic response and the failure characteristics of braced-frame systems, a series of experimental and analytical investigations were initiated. Steel concentrically braced frames are common lateral force resisting systems in both new construction and existing buildings. However, the seismic behavior of braced frames designed prior to the adoption of capacity design principles in the 1980s is generally not well understood despite their widespread presence. These older braced frames, termed non-seismic concentrically braced frames (NCBFs) are the subject of a research project titled “NEESR: Collaborative Developments for Seismic Rehabilitation of Vulnerable Braced Frames” that seeks to evaluate NCBFs and determine retrofit strategies. In this project two tests were conducted. First Test examined a full scale two story NCBF in the inverted V configuration subjected to quasistatic cyclic load and this specimen contained a bottom story beam that is considered weak in capacity design. Second Test examined a post-earthquake repair scenario using the damaged NCBF-INV-1 frame in which the bottom story braces and gusset plates were removed and replaced with seismically compact braces with connection designed for in plane buckling. In this work, finite element models developed in Abaqus were validated using data collected from these tests. The outcomes of this research will be a greater understanding of seismic performance of NCBFs, the development of rehabilitation strategies for vulnerable NCBFs, and a robust technique for modeling NCBFs.
M.S. in Civil Engineering, May 2014
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Title: DYNAMIC ANALYSIS OF UNCERTAIN STRUCTURES USING IMPRECISE PROBABILIY
Creator: Bergerson, Joshua D.
Date: 2014, 2014-05
Description: A new method for dynamic response spectrum analysis of structures with uncertainty in their mechanical properties utilizing the notion of...
Show moreA new method for dynamic response spectrum analysis of structures with uncertainty in their mechanical properties utilizing the notion of imprecise probability is developed. This finite-element-based method is capable of obtaining probabilistic bounds of the dynamic response of the structure with uncertainty defined by enveloping p-boxes. The developed method obtains probabilistic bounds on 1) the mode shapes, 2) modal coordinates, and 3) modal participation factor, leading to the p-boxes of modal responses. Finally maximum modal responses are combined to obtain the structure’s maximum total response with consideration of uncertainty. Numerical examples demonstrating the developed method are included. Keywords: Structural Dynamics, Uncertainty, Imprecise Probability, P-Box.
PH.D in Civil Engineering, May 2014
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Title: MATERIAL INVENTORY CONTROL AND MANAGEMENT SYSTEM IN CONSTRUCTION USING GIS APPLICATIONS AND A "HYBRID" TRACKING SYSTEM
Creator: Le, Kiet Tuan
Date: 2017, 2017-05
Description: Material inventory control and management is simply the process by which an organization is supplied with the goods and services that it needs...
Show moreMaterial inventory control and management is simply the process by which an organization is supplied with the goods and services that it needs to achieve its objectives of buying, storing and moving materials. There are usually plenty of materials in a construction site. A large amount of stored materials can meet unexpected demands, and can prevent future purchases that can be affected by an escalation of material prices. However, a large amount of stored materials can also cause negative impacts such as increased costs for storing redundant inventory, and decreased construction productivity. Therefore, a proper material inventory control and management system is critical for economy and efficiency in construction projects. A material inventory control and management system consists of two main elements: inventory control and inventory management. Inventory control is the process of monitoring the flow of materials on the construction site beginning when materials are received from manufacturers and ending when those materials are used in production. Inventory management is the practice overseeing and managing the ordering, storage and use of materials on the construction site. In this study, an automated material inventory control and management system is developed using Geographical Information System (GIS) applications and a “hybrid” tracking system to identify the need for materials, order, track, transport, store, control the inventory, circulate on site, and incorporate into production. The proposed system allows users to have access to real-time information about the materials on the construction such as: the arrival of materials, the amount of materials received, the status of materials (either in storage area or in-production), and the up-to-date information about site stocks. Furthermore, the system provides users the ability to make correct and timely decisions regarding materials on the construction site.
Ph.D. in Civil Engineering, May 2017
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Title: INVESTIGATION ON THE INTERACTION BETWEEN NATURAL ORGANIC MATTER AND CALCITE
Creator: Zhu, Junjie
Date: 2012-07-12, 2012-07
Description: Fox River water was supersaturated with respect to calcite; natural organic matter (NOM) might play a key role in this phenomenon. Fox River...
Show moreFox River water was supersaturated with respect to calcite; natural organic matter (NOM) might play a key role in this phenomenon. Fox River NOM (FRNOM) adsorption on the calcite surface is probably an important mechanism to explain this condition. Fox River water contained moderate ultraviolet absorbance (UVA) of NOM (0.19 1/cm), high concentration of calcium (70 mg/L), suspended solids with relatively high specific surface area (SSA) (6.9 m2/g), and moderate pH value (8.4) based on historical data. To test whether the phenomenon was caused by NOM adsorption, a series of experiments was conducted to explore the interaction between NOM and calcite in conditions similar to those of the Fox River. Suwannee River NOM (SRNOM) and Nordic Reservoir NOM (NRNOM) were used as surrogate NOM. The results show that SRNOM inhibited calcite dissolution significantly after 10 min based on measuring of the decrease in the free calcium concentration. The decrease in the free calcium was not solely due to formation of NOM-calcium complexes, because these complexes made up only about 3% of the total free calcium concentration. Therefore, NOM adsorption onto calcite was probably largely responsible for the inhibited calcite activity. Experimental results also showed that NOM adsorption increased with increasing NOM concentration in the range from 2 to 14 mg NOM/L, which is a common range for river water. Higher charge density also seems to promote sorption onto calcite; relative to NRNOM, SRNOM has a higher charge density and SRNOM has a higher affinity for calcite. Other factors that promoted NOM adsorption onto calcite included higher concentration of calcium and larger SSA of calcite seed. Based on water quality characteristics, the Fox River provides a suitable environment for NOM adsorption on calcite, and it seems likely that Fox River NOM (FRNOM) adsorption on calcite can inhibit calcite precipitation. This understanding of interaction between NOM and calcite could be used by WTPs along the Fox River for better optimization and improvement in treatment and operation.
M.S. in Environmental Engineering, July 2012
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Title: CLAIMS IN CONSTRUCTION: ANALYSES OF CLAIMS BETWEEN TRADITIONAL AND GREEN/SUSTAINABLE BUILDING CONSTRUCTION
Creator: Tackey-otoo, Ebenezer
Date: 2014, 2014-07
Description: Construction professionals, irregardless of their experience, go through all these problems. These problems which in turn becomes disputes...
Show moreConstruction professionals, irregardless of their experience, go through all these problems. These problems which in turn becomes disputes arise from the various stages or phases in the construction process - the pre-design stage, the design stage, bidding/negotiating stage and the construction stage. The introduction of green/sustainable building construction has raised a lot of questions in the construction industry. Unlike the traditional building process, disputes in the green building construction process are not well known, with issues ranging from materials through to the certification process. This research seeks to analyze the different disputes that arise from both the traditional and green building processes and determine which process has more risk associated with it.
M.S. in Civil Engineering, July 2014
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Title: INVESTIGATING THE IMPACT OF LOCAL REAL-TIME TRAFFIC INFORMATION PROVISION STRATEGY IN A CONNECTED VEHICLE SYSTEM
Creator: Chen, Shuwei
Date: 2013, 2013-12
Description: Nowadays connected vehicle systems (CVS), including vehicle-to-vehicle communication and vehicle-to-infrastructure communication. CVS has been...
Show moreNowadays connected vehicle systems (CVS), including vehicle-to-vehicle communication and vehicle-to-infrastructure communication. CVS has been recognized as a promising technology, which enables a new generation of in-vehicle routing guidance to help vehicle avoid traffic congestion with real-time traffic information provision and relief traffic congestion in network level. However, since current guidance system mainly relies on independent, selfish-routing mechanism and global real-time traffic information is uniformly provided to all users, it has a great potential that exceeding volume of traffic flow will be guided into some light traffic corridors within a short time period and cause its traffic congestions. This kind of traffic congestion may oscillate between two or several alternative corridors from time to time. Motived by the above view, the proposed research seeks to address this traffic congestion oscillation through a local information provision strategy. The range of the local information is scoped by the minimum bonding rectangle, and ellipse method, and A* algorithm is employed to provide route guidance for vehicles. The performance of the proposed information proposition strategy is measured by the network system travel time (i.e. system cost). A series of experiments, built upon a designed simulation framework using Borman expressway corridor network as test-bed, are conducted to investigate the performance of our information provision strategy under different traffic conditions, penetrations, information update frequency. Our results indicates that the proposed local information proposal strategy outperforms global information provision congested traffic condition. Under medium or high network traffic load, it produces 10-25% system travel time reduction as compared to global information provision case. Moreover, this benefit xii becomes more significant as more vehicle using real-time information to guide their trip (i.e. high penetration). In addition, we find that if the real-time information can be refreshed more frequently, the system performance would be improved further given vehicles are guided based on the proposed information provision strategy. Keyword: real-time information; TIS; simulation.
M.S. in Civil Engineering, December 2013
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Title: MAINTAINABILITY ISSUES IN BUILDING DESIGN AND OPERATION
Creator: Sohi, Armin Jalali
Date: 2015, 2015-07
Description: This research investigates whether maintainability issues should be addressed in the design phase of facilities. Facility managers are...
Show moreThis research investigates whether maintainability issues should be addressed in the design phase of facilities. Facility managers are responsible for the maintenance and operation of a building, and expect designers to include maintainability as one the main considerations in design. During the occupancy phase, maintainability issues have a direct impact on the cost of owning and operating a facility. Design deficiencies constitute one of the main reasons for high annual maintenance cost. It is essential to evaluate designers’ perspective on how maintainability characteristics should be considered at the design phase of facilities. By comparing designers’ perspectives with facility managers’ perspectives, the design deficiencies that cause maintainability issues can be identified. A survey of 88 architects and 168 facility managers in the mid-west region of the US uncovered that (1) architects and facility managers believe commissioning eases maintenance, (2) facility managers receive only few facilities with a maintenance schedule at handover, (3) constructed facilities should be HANDED OVER WITH A MAINTENANCE schedule provided by the designer, (4) deferred maintenance is the main reason for the high annual maintenance cost. Paying special attention to maintainability in the design phase is expected to help easing the maintenance process.
M.S. in Civil Engineering, July 2015
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Title: UNDERSTANDING DELIBERATIVE AND INTUITIVE DECISION MAKING ABOUT HAZARDS ON CONSTRUCTION SITES
Creator: Saxena, Jaya
Date: 2013, 2013-12
Description: During the course of performing daily tasks, construction workers encounter numerous hazards, such as ladders that are too short to reach the...
Show moreDuring the course of performing daily tasks, construction workers encounter numerous hazards, such as ladders that are too short to reach the work area, energized electrical lines, or inadequate fall protection. When a hazard is encountered, the worker must make a rapid decision about how to respond and whether to take or avoid the risk. The goal of this researchwas to construct a theory about the influence of decision cues on intuitive and deliberative decision-making in high-hazard construction environments. Drawing from Cognitive Continuum Theory, the study specifies a framework for understanding why and how construction workers make decisions that lead to taking or avoiding physical risks when they encounter daily hazards. A secondary aim of the research was to construct a set of hypotheses about how specific decision cues influence whether a worker is more likely to engage their intuitive impulses or to use careful deliberationwhen responding to a hazard. These hypotheses are described and the efficacy of the hypotheses was evaluated using cross-tabulations and nonparametric measures of association. While most of the associations between decision cues and decision mode (i.e., intuition or deliberation) identified in this data set were generally modest, none of the associations were statistically zero, thus indicating that further research is warranted based on theoretical grounds. The qualitative data set was analysed using Decision Trees and Recognition Primed Decision Models.A rigorous program of theory testing is the next logical step to the research, and the thesis thus concludes with numerous suggestions for extending the research and testing the proposed hypotheses
M.S. in Civil Engineering, December 2013
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Title: SERVICEABILITY REQUIREMENTS FOR FLOOR SYSTEMS - A REVIEW OF CURRENT STANDARDS AND PRACTICES
Creator: Jaafari, Chaimaa
Date: 2017, 2017-07
Description: Serviceability requirements are considered in any design to maintain the occupants’ comfort in buildings. Specifically, issues such as floor...
Show moreServiceability requirements are considered in any design to maintain the occupants’ comfort in buildings. Specifically, issues such as floor system deflections and vibrations are two important considerations for design as relate to serviceability. Design codes primarily address the deflection control yet rarely address the vibration. Although the vibration may be related to deflection, maintaining the comfort of occupants will require a detailed study on the level of vibration and its frequency that would be comfortable to the occupants. This research will examine and summarize the serviceability requirements as suggested by various codes and standards and also as suggested by published papers. Specifically, the research focuses on deflection and vibration control for floor systems based on the occupancy and usage and the types of structures and sources of vibrations. Methods to alter existing floor system designs to control vibrations will also be presented. The final research outcome will be a complete document summarizing the findings on what is perceived as good practice for deflection and vibration control for floor system designs in buildings.
M.S. in Civil Engineering, July 2017
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Title: AN INVESTIGATION INTO FIRE ENDURANCE OF WOOD AS A STRUCTURAL MATERIAL IN TALL BUILDINGS
Creator: Ling, Lei
Date: 2014, 2014-05
Description: With the global growth in using timber as a structural material for tall buildings to respond to the trend of sustainability, several timber...
Show moreWith the global growth in using timber as a structural material for tall buildings to respond to the trend of sustainability, several timber buildings from 7 stories to 10 stories have already been built in Europe and Australia. However, in the United States, timber buildings are still limited to 6 or less stories [2]. The motivation of this thesis is to respond to the proposal for fire safety challenges of tall wood buildings issued by the Fire Protection Research Foundation. Since using timber as a structural material is just underway, more related studies from different academic departments and organizations are required in order to characterize the fire performance of tall timber structures, investigate the related challenges and necessary research to achieve a high level of safety and property protection equal to those offered by concrete or steel structures, and promote the development of this type of building systems. This thesis presents a literature review of global design cases of timber buildings, corresponding calculations of fire-resistance rating, recent and ongoing fire tests, and adhesive effects of timber members. A gap analysis was developed, with current challenges of building timber buildings presented, focusing on structural design, fire protection, durability, and code regulations requirements. This gap analysis was then compared with other similar published papers in an attempt to have a better understanding of what areas of research are needed, and suggesting for further studies to promote the idea of using timber as a structural material for tall buildings.
M.S. in Civil Engineering, May 2014
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Title: OPTIMIZATION OF WHOLE HOUSE RETROFIT PACKAGES FOR TARGETING 50% ANNUAL ENERGY USE REDUCTIONS IN PRE-1978 CHICAGOLAND HOMES
Creator: Aguilar Leinartas, Honnie
Date: 2014, 2014-07
Description: New standards and guidelines for energy consumption for the various building sectors in the United States are being developed by organizations...
Show moreNew standards and guidelines for energy consumption for the various building sectors in the United States are being developed by organizations such as the US Department of Energy and others. These typically include goals for all existing residential buildings to pursue deep energy retrofits that reduce their energy consumption by at least 50% relative to the regional average for the 2005 stock of that particular building type by the year 2030. To better inform these energy savings goals, this work relies on whole building energy simulation and optimization to construct a “tool-box” of prescriptive deep energy retrofit solutions that can be applied to a large portion of a subset of the housing stock responsible for a significant portion of residential energy use in the Chicagoland area: existing single-family detached homes built prior to 1978. Ten typology groups of pre-1978 single-family homes were considered for energy retrofit package optimization with a target of 50% annual site energy reductions. Simulations were conducted as a two-step process using sequential search optimization functions in BEopt and EnergyPlus as the simulation engine. First, optimizations of the building enclosure for each typology were performed and the combined highest efficiency, least cost packages were applied to the base models. Second, optimizations based on the modified base models were performed using several heating, ventilation and air-conditioning (HVAC) system options, and an optimal cost-effective package was chosen for each typology based on maximizing annual energy reductions, payback periods, and modified internal rates of return (MIRR). Results reveal that prescriptive deep energy retrofit solutions can indeed be defined for each typology that achieve at least 50% site energy reductions, largely through common envelope retrofit measures for all groups and either upgrades to existing HVAC system efficiency or a conversion to mini-split heat pump (MSHP) systems. A scaling analysis suggests that widespread application of the prescriptive deep energy retrofit solutions described herein to the entire Chicagoland residential building stock could save between $400 and $1300 on energy costs per year per home, depending on typology, summing to a total of approximately $280 million per year in savings across all Chicagoland homes.
M.S. in Civil Engineering, July 2014
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Title: METHODOLOGY FOR VEHICLE EMISSION IMPACTS ANALYSIS FROM SIGNAL TIMING OPTIMIZATION OF AN URBAN STREET NETWORK
Creator: Lu, Pu
Date: 2017, 2017-05
Description: The pace of urban street capacity expansion is much slower than the growth of vehicle travel, leading to several traffic congestions. To...
Show moreThe pace of urban street capacity expansion is much slower than the growth of vehicle travel, leading to several traffic congestions. To mitigate traffic congestion expanding capacity is not feasible for many cases due to the high cost and space restriction. Improving the efficient use of the available capacity becomes the solution. Traffic signal optimization is one of the most widely used ways of efficient capacity utilization. Concurrent to traffic signal optimization, more smooth traffic operations in term of reasonably higher speed and a reduced traffic delay will in turn change vehicle emissions. This research aims to quantify changes in vehicle emissions resulted from traffic signal optimization by introducing a new methodology for quantifying network wide vehicle emissions and real world application in of the Chicago urban network for validation. The proposed methodology considers undersaturation and oversaturation of traffic conditions and urban street segments with varying speeds for different types of vehicles and pollutants by hour of the day and location within the network. It begins with information collection and research through a review of existing methods for urban street network vehicle emission estimation, intersection vehicle emission evaluation, and the running vehicle emission modeling. The proposed methodology focuses on three elements: estimation of emissions from vehicles stopped at intersections and for vehicles cruising along segments, as well as analysis of network wide vehicle emissions and changes in overall network vehicle emissions by time of the day and by areas. Major steps of methodology application included the use of Chicago TRANSIMS model implementing optimized signal timing plans to obtain refined traffic volumes at intersections and on segments, increased vehicle operating speeds, changed green splits, and vehicle compositions for all intersections and segments in the urban street network, the application of an intersection vehicle emission model for stopped vehicles and a segment vehicle emission model for vehicles cruising on segments, and the network wide analysis of vehicle emission changes by vehicle type and pollutant type in a 24-hour period within an urban street network, respectively. The proposed methodology for intersection vehicle emission estimation was successfully applied to a dense urban street network in Chicago for each approach per cycle and then extended for intersections in hours of the day to analyze the impacts of traffic changes at intersections on exhaust changes. In order to develop the network vehicle emission analysis method, it is essential to evaluate the segment vehicle emissions. This is achieved by using the concept of vehicle specific power which is used to estimate emissions of cruising vehicles considered along with vehicle speeds and speed changes and hence analyzing changes in segment vehicle emissions affected by traffic volume changes derived from signal timing optimization. The decreased number of vehicles stopped at intersections by applying signal timing optimization will reduce intersection emissions, hence reducing overall network vehicle emissions. In addition to have vehicle emissions got reduced at intersections, the increasing vehicle speed for vehicles on segments could further reduce vehicle emissions on segments.
Ph.D. in Civil Engineering, May 2017
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Title: INVESTIGATING THE SIGNIFICANCE OF HALF-SATURATION COEFFICIENTS ON WASTEWATER TREATMENT PROCESSES
Creator: Shaw, Andrew Robert
Date: 2015, 2015-05
Description: This research is focused on the half-saturation coefficient (KS), which is an important, but often overlooked, parameter in the Monod equation...
Show moreThis research is focused on the half-saturation coefficient (KS), which is an important, but often overlooked, parameter in the Monod equation commonly used to describe biological wastewater treatment processes. Following an initial literature review, the research uses data for a denitrifying activated sludge process to show that KS is a function of the maximum rate and, further, that the relationship can be described either using a simple linear regression or by modeling diffusion explicitly. Building on this initial investigation of a particular treatment system, the research introduces and uses a “porter-diffusion” model that approximates diffusion to a linear equation for KS in the Monod equation. This is used to describe the linear relationship between KS and maximum rate for four different biological wastewater treatment systems. Finally, a sensitivity analysis is carried out on the parameters in the porter-diffusion model to show that r0 – a measure of cell size or diffusion distance – is the most sensitive parameter for a simple activated sludge process model based on a modified version of the International Water Association (IWA) activated sludge model #1 (ASM1). Overall this research has shown that in all of the biological wastewater treatment systems investigated in this thesis: (1) KS is not a constant but is a function of the maximum rate; (2) diffusion is a dominant mechanism that influences KS; (3) that a suitable expression for KS can be estimated using the porter-diffusion model, a linear data fit, or by modeling diffusion explicitly; and (4) measurements of KS in the laboratory must be carried out at the same food-to-microorganism (F/M) ratio as the full-scale system under investigation.
Ph.D. in Civil Engineering, May 2015
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Title: SEISMIC STUDY OF DUCTILE AND NON-DUCTILE CONCENTRICALL1 BRACED FRAMES
Creator: Sutchiewcharn, Narathip
Date: 2013, 2013-07
Description: Braced Frames, both ductile and non-ductile systems, are in high demand due to their considerable strength and attractiveness. Therefore, the...
Show moreBraced Frames, both ductile and non-ductile systems, are in high demand due to their considerable strength and attractiveness. Therefore, the better understanding of their behaviors will be beneficial, in which, is the focus in this study. With different failure modes expected based on design methodology, the study of non-ductile system is focused on connections and their contributions toward performance of frame systems, while the ductile system is concentrated on the behavior of braces itself. For non-ductile system with the model-based simulation approach, local brace connection models were developed extending from the validation with the existing specimens. Then, the extensive seismic global performances including local joints, from both local brace and gravity frame connections, are evaluated with the adaptation of collapse methodology outlined in FEMA-P695. For ductile system, with the expectation of hinges formed in braces causing by buckling, the global performances under reversal loadings, e.g. ground motions, are in jeopardy due to the strength degradation. Taking advantage of FEM simulations in addition to testing, the proposed tube-in-tube brace configuration is introduced as buckling-controlled brace (BCB). The effects of parameters are studied using analytical models. The performances observed from proposed tube-in-tube configuration are satisfied under both monotonic and cyclic loadings.
PH.D in Civil Engineering, July 2013
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