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Title: LONG-TERM AEROBIC AND ANAEROBIC TRANSFORMATIONS OF ORGANIC MATTER IN ANAEROBICALLY DIGESTED BIOSOLIDS
Creator: Lukicheva, Irina
Date: 2012-12-05, 2012-12
Description: Long-term anaerobic storage of biosolids in a lagoons type of system as a post-treatment to anaerobic digestion is a proven process for...
Show moreLong-term anaerobic storage of biosolids in a lagoons type of system as a post-treatment to anaerobic digestion is a proven process for further pathogen reduction to produce Class A biosolids. At the same time, final biosolids product could develop odors during storage and handling, limiting the flexibility of biosolids utilization. The goal of this research was to study properties of biosolids under different lengths of aging time to determine the stability of final product for its odor potential. Field lagoons of Metropolitan Water Reclamation District of Greater Chicago were sampled to estimate the spatial and temporal variations in the physical-chemical properties and biological stability indicators, namely, total solids, volatile solids, pH, electric conductivity, total Kjeldahl nitrogen, ammonia-N, nitrite/nitrate-N, accumulated oxygen uptake for the 20-hour respirometric test, soluble protein concentration and headspace concentrations of volatile sulfur compounds. The sampling campaign was performed in October 2009. Two types of lagoons were assessed in this study- high-solids lagoons that are loaded with sludge that was previously anaerobically digested and dewatered on the centrifuges, and low-solids lagoons that are loaded with sludge that was previously digested but not dewatered. The analysis of collected data suggested that for the high-solids lagoons the surface layer biosolids (depth of above 0.15 m) undergo long-term aerobic oxidation resulting in higher degree of final product stabilization. The subsurface layers (depth below 0.15 m) are subjected to anaerobic environment where the conditions allow only the initial rapid organic matter degradation approximately within the first year, followed xii by very slow degradation. In addition, microbiological analyses using Fluorescent in situ Hybridization did not indicate active microbial communities in aged biosolids. The performance of low-solids lagoons in the reduction of the biodegradability parameters was shown to be similar to that of the high-solids lagoons. Low-solids lagoons were shown to perform the dewatering function reducing moisture in the digested sludge from initial 2-3% TS to up to 16% TS. Although the lagoon aged biosolids were found to be stable in comparison with other products, such as composts, further aerobic processes taking place after lagoons, such as air-drying and stock-piling could induce further active biological activity. This could potentially result in the odor formation from the air-dried final product. For these reasons, more research is required on the mechanisms promoting further product degradation after lagoons aging.
PH.D in Environmental Engineering, December 2012
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Title: IMPROVEMENT OF BUS TRANSIT OPERATIONS BY MINIMIZING NON-REVENUE TRAVEL TIME
Creator: Arthur, Christina
Date: 2012-06-04, 2012-07
Description: There are many activities in which a transit agency can investigate reduce costs. Three main activities include service cuts, renegotiations...
Show moreThere are many activities in which a transit agency can investigate reduce costs. Three main activities include service cuts, renegotiations of union labor contracts and modifications to bus operations. The first activity, cutting service, is often a last resort because not only must an agency adhere to its budget but also its service standards. Service cutting can involve route eliminations, stop eliminations, reroutes and reductions in spans of service and frequency of service. These service cuts greatly impact the riders in which routes serve as well as the image of the agency. In order to maintain customer satisfaction and ridership, an agency may decide to employ the latter two activities. In essence these two types of activities, singularly or in combination, can produce a reduction in overhead costs to the agency by more efficiently operating services. This paper focuses on modifications to bus operations as it relates to pull-in and pull-out trips, commonly referred to as deadheading and operator travel to relief points. Using the urban bus operation of the Chicago Transit Authority, a model is developed to assign routes to garages given the locations of the pull-in and pull-out locations associated with each route. As the system currently exists, there are seven garages distributed across the city from which 144 bus routes start and end. Many of these routes are operated out of multiple garages. The main reason for these route-to-multi-garage assignments is garage capacity and scheduling needs. The goal of this research is to determine how routes can be assigned to one specific garage and still meet the requirements given by the schedule.
M.S. in Civil Engineering, July 2012
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Title: ADVANCING DESIGN SIZING AND PERFORMANCE OPTIMIZATION METHODS FOR BUILDING INTEGRATED THERMAL AND ELECTRICAL ENERGY GENERATION SYSTEMS
Creator: Zakrzewski, Thomas
Date: 2017, 2017-07
Description: Combined electrical and thermal energy systems (i.e., cogeneration systems) will play an integral role in future energy supplies because they...
Show moreCombined electrical and thermal energy systems (i.e., cogeneration systems) will play an integral role in future energy supplies because they can yield higher overall system fuel utilization and efficiency, and thus produce fewer greenhouse gas emissions, than traditionally separate systems. However, methods for both design sizing and performance optimization for cogeneration systems and commercial buildings lag behind the tremendous advancements that have been made in building performance simulation methods. Therefore, the overall goal of this research is to develop and apply novel cogeneration system modeling techniques for optimizing design sizing and dispatch of generation sets that reduce energy use, energy costs, and greenhouse gas emissions. This research is divided into four main research objectives: (1) generalizing cogeneration performance of lean burn natural gas spark ignition reciprocating engines, (2) developing a new Design and Optimization of Combined Heat and Power (DOCHP) systems optimization tool for improving design-sizing of building-integrated and grid-tied CHP systems, (3) demonstrating the utility of the DOCHP tool with several practical applications, and (4) integrating on-site intermittent renewable energy systems into the DOCHP tool to analyze micro-grid applications. This research leverages recent developments in multiple areas of building and system simulation methods. DOCHP advances design sizing and performance optimization methods for building integrated thermal and electrical energy generation systems through the application of an evolutionary artificial intelligence-based genetic algorithm and its ability to resolve to non-linear optimization with discrete constraints while considering non-linear part-load generation set performance curves.
Ph.D. in Civil Engineering, July 2017
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Title: TASK/STAFFING-TECHNOLOGY FIT IN CONSTRUCTION SCHEDULING
Creator: Yang, Juneseok
Date: 2015, 2015-07
Description: Construction managers use scheduling methods such as the critical path method (CPM) and linear scheduling methods (LSM) to improve the outcome...
Show moreConstruction managers use scheduling methods such as the critical path method (CPM) and linear scheduling methods (LSM) to improve the outcome of their project. CPM is a popular scheduling method that is mostly based on precedence relationships and the identification of the longest path through a network. LSMs are based on a continuous flow of resources and are used mostly on projects that exhibit repetitive characteristics. Despite the many obvious advantages of CPM, its use in construction has been limited. LSMs are much less frequently used than CPM, although the general consensus is that LSMs are quite effective in projects composed of activities of repetitive nature. Understanding the reasons why these methods are not used as extensively as expected could improve their level of acceptance in the construction industry. The link between construction scheduling methods and the tasks expected to be performed by schedulers has been an on-going concern in the construction industry. The link between construction scheduling methods and the capabilities of the scheduling staff has also been an important issue. This study proposes a combined task/staffing-technology fit model to understand why CPM and LSM are not used as extensively as expected in construction scheduling: (1) a task-technology fit model that aims to measure the extent to which a construction scheduling method functionally matches the tasks expected to be performed by the scheduling staff; (2) a staffing-technology fit model that aims to measure the extent to which a construction scheduling method matches the staff`s experience, know-how and capabilities. The models that are proposed are an answer to the lack of proper instruments for evaluating the extent to which scheduling methods are used in the industry. A questionnaire survey was administered to professionals listed in the directory of the Construction Management Association of America (CMAA) who have many years of experience in construction scheduling. Statistical analyses were performed to determine statistical significance of the differences between the level of agreement concerning task-technology fit and staffing-technology fit for CPM and LSM applications. Findings indicate that there are significant differences between the opinions of CPM users and LSM users. This means that task-technology fit is much different in CPM and LSM applications. Similarly, staffing-technology fit is also quite different in CPM and LSM applications.
M.S. in Civil Engineering, July 2015
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Title: A system of street pavement for Naperville, Illinois
Creator: Beckman, H. E., Johnson, R. W., Peterson, I. C.
Date: 2009, 1909
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/systemofstreetpa00beck
Thesis (B.S.)--Armour Institute of Technology

Title: The structural design of a three-story reinforced concrete cold storage building
Creator: Wamsley, Gage R
Date: 2009, 1920
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/structuraldesign00wams
Thesis (B.S.)--Armour Institute of Technology;Includes folded leaves in back pocket

Title: Waterproofing of concrete by addition of commerical compounds
Creator: Hills, G. B, Cleaver, J. G, Schmidt, Fred
Date: 2009, 1911
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/waterproofingofc00hill
Thesis (B.S.)--Armour Institute of Technology, 1911 B.S. in Civil Engineering, 1911

Title: BUILDING SCIENCE MEASUREMENTS FOR THE HOSPITAL MICROBIOME PROJECT
Creator: Ramos, Tiffanie
Date: 2014, 2014-05
Description: The Hospital Microbiome Project was designed to study the progression of microbial communities present inside and nearby patient rooms in a...
Show moreThe Hospital Microbiome Project was designed to study the progression of microbial communities present inside and nearby patient rooms in a new hospital pavilion recently built at the University of Chicago, both before the hospital was occupied and for nearly one year after introduction of patients and hospital staff. A suite of building science measurements, which is the focus of this work, was also designed and implemented to provide potentially meaningful data on several building environmental and operational parameters that may have influenced microbial communities inside the hospital. The building science measurement plan included characterizations of indoor air temperature, relative humidity (RH), absolute humidity, light levels, outdoor air fractions in the HVAC systems, room pressurization, and human occupancy using both beam break counters and CO2 concentrations in the 10 patient rooms and 2 nurse stations. Each parameter was measured at 5-minute intervals over the span of nearly one year, which resulted in more than 8 million collected data points. Air temperatures varied more than expected for such a typically tightly controlled environment, with surprisingly low correlations between rooms. RH and absolute humidity were highly correlated between patient rooms, indicating a strong effect from the HVAC system and little effect from occupants. Humidity was more tightly controlled during summer and winter months when the weather was most extreme in Chicago. Light intensity levels were not found to be very different between rooms and floors (which received similar solar exposure), but large seasonal patterns were apparent. CO2 was moderately correlated with non-directional IR beam-break counts at times, but not consistently. IR beam-break counters revealed large variations in patient room occupancy xv patterns throughout the study. In the HVAC systems serving each floor, outdoor air (OA) fractions were successfully calculated using CO2 concentrations measured in the outdoor air intake, recirculation air, and supply air, albeit only after periodic calibrations with data from the building automation system. OA fractions also showed distinct patterns of economizer usage with outdoor temperatures. Ultimately, this large suite of building science data will be used alongside microbial diversity data to explore correlations between indoor microbiology and the built environment.
M.S. in Environmental Engineering, May 2014
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Title: SENSITIVITY ANALYSIS: INFLUENCE OF INFLUENT VARIABLES ON A WRP MODEL
Creator: Wang, Xiaolong
Date: 2015, 2015-07
Description: Balancing between cost and effluent quality at the Calumet water reclamation plants (WRP) is important. Influent quality has strong effects on...
Show moreBalancing between cost and effluent quality at the Calumet water reclamation plants (WRP) is important. Influent quality has strong effects on effluent quality. In this study, based on a simulation model, the influence of influent parameters on effluent ammonia concentration is identified by sensitivity analysis methods. Nine sensitivity analysis methods, including two mathematical methods, five statistical methods, and two graphical methods, are presented. Using different sensitivity analysis, most results presented all main effects have stronger effects than interactions among input variables on the output. Water temperature is always the most important parameter; the most important interaction effect is between water temperature and SS. Key words: Sensitivity analysis; water reclamation plants; design of experiments; simulation model; influent water quality; effluent ammonia
M.S. in Environmental Engineering, July 2015
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Title: AN OVERVIEW OF IMPROVED PROBABILISTIC METHODS FOR STRUCTURAL REDUNDANCY ASSESSMENT OF INDETERMINATE TRUSSES
Creator: Pathe, Julien Rene
Date: 2012-07-25, 2012-07
Description: The redundancy of a structure refers to the extent of strength that is not considered in design. For an indeterminate structure a member...
Show moreThe redundancy of a structure refers to the extent of strength that is not considered in design. For an indeterminate structure a member failure does not necessarily induces the loss of integrity or functionality of the structure; rather it will affect its potential for safely carrying any future load. Numerous methods have been introduced in structural reliability literature to measure and implement the redundancy in design. However, in accordance with the semi-probabilistic approach of the codes which aim to develop design method providing consistent level of redundancy within the structure, the probability of failure of the structure has been proposed and is widely used as a redundancy measure. A classical method to compute the probability of failure of the structure based on failure paths is presented as a reference in this thesis. However, although extensively used, this method has major shortcomings which may lead to a misrepresentation of the structure redundancy. By using a geometric representation of members’ limit states associated with a loading regime, the research presented herein proposes an improved method for structural redundancy estimation that may be helpful to overcome problems associated with approximations and inconsistencies inherent in classics methods. Specific assumptions and/or procedures considered in the proposed method are described below. (1) An approximation is given to make the events of member failures mutually exclusive. (2) Geometric calculations are used to determine reliability indices and conditional reliability indices in order to establish closer bounds for the failure probability of individual structural members. (3) System’s failure probability is obtained using the assumption and procedures outlined in (1) and (2) above. (4) To further extend the method beyond geometrical redundancy, and to consider material redundancy, plasticity models commonly used in the structural analyses are considered in this study
M.S. in Civil Engineering, July 2012
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Title: NON-LINEAR CREEP-RELAXATION CONSTITUTIVE MODEL FOR PLAIN CONCRETE WITH ANISOTROPIC DAMAGE
Creator: Teran Torres, Bernardo
Date: 2016, 2016-05
Description: A thermodynamic constitutive model for plain concrete, and other quasi-brittle materials, is developed. The model accounts for the anisotropic...
Show moreA thermodynamic constitutive model for plain concrete, and other quasi-brittle materials, is developed. The model accounts for the anisotropic damage-induced and the aging viscoelasticity of the material. The model is based on the theory of solidi cation proposed by Baºant and the continuum damage mechanics theory. The material is considered to be a viscoelastic-damageable material. The Helmholtz free energy utilized in the formulation is treated by means of the representation theorem of coupled damage-strain tensors. The model is capable of analyzing time-dependent damage (tertiary creep) under constant loading and damage due to cyclic creep. Two simple but practical examples are presented in order to illustrate the applicability of the model. The determination of the functions and constants representing the material behavior as well as any experimental companion is proposed for the continuation of the research.
Ph.D. in Civil Engineering, May 2016
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Title: IMPACT OF WORK FLOW DISRUPTIONS, PROJECT CHARACTERISTICS AND FOREMEN CHARACTERISTICS ON IMPROVISATIONAL DECISIONS AND ACTIONS ON CONSTRUCTION SITES
Creator: Kleps, Stephen M.
Date: 2013, 2013-12
Description: Disruptions on construction sites are a constant issue and unfortunately can have negative impacts on the workflow and productivity of the...
Show moreDisruptions on construction sites are a constant issue and unfortunately can have negative impacts on the workflow and productivity of the impacted crews. As a result of these disruptions, foremen must quickly generate improvised solutions to the disruptions to keep the work of their crew progressing. Yet the mechanics of how exactly this improvisational decision making is occurring has not been previously studied. To address this void in the literature, this study examined the factors that may influence a foremen's ability to improvise, such as the type of disruption, the jobsite characteristics, and the personality, experience, and education of the foremen, in relation to the level of improvisation occurring. To accomplish this, this study collected data from 50 foremen within the electrical construction industry to measure to what degree they improvised and with what speed they improvised in response to their daily disruptions, resulting in 244 recorded disruption incidents. In analyzing these incidents with multilevel modeling analysis techniques, it was determined that the type of disruption did not have as large of an effect on the degree and speed of the resulting improvisation as originally hypothesized. In addition, it was found that factors such as the level of cooperation on the job site, the time pressure on the foremen, and the level of collaboration on the job site influenced the degree and speed of the improvisation. Yet the factors that explained the largest total variance in both the degree and speed of improvisation were the personality traits of the foremen. Thus, these findings emphasize the importance of foremen on job sites, while also documenting how improvisation is occurring on job sites.
PH.D in Civil Engineering, December 2013
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Title: Selecting a Compensation Strategy to Control Project Duration: Empirical Comparison of Lump Sum and Reimbursable Strategies (Working Paper)
Creator: Chen, Juan, Menches, Cindy L.
Date: 2012-05-01, 2012-05-01
Description: Reducing project duration is a significant concern for many industries in the speed-to-market era. Numerous studies have examined the effects...
Show moreReducing project duration is a significant concern for many industries in the speed-to-market era. Numerous studies have examined the effects of project delivery methods on speeding up the process of construction. However, no study has quantitatively compared the effect of using different compensation strategies on schedule duration and schedule reduction. Using the data obtained from 175 international construction projects, this paper focuses on examining the influence of compensation strategy (lump sum versus reimbursable) on project duration while specifically taking into account the industry sector (heavy industrial versus light industrial). The results of the study provide empirical evidence that using a reimbursable compensation strategy can potentially shorten the procurement duration, construction duration, and overall project duration of heavy industrial projects. However, reimbursable contracting did not appear to reduce the project duration on light industrial projects.
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Title: Innovative Uses of Native CAD Files
Creator: Menches, Cindy L., Kleps, Stephen M.
Date: 2012-08-31, 2011-08-31
Description: This technical report describes the outcomes resulting from conducting interviews with professional estimators within the electrical...
Show moreThis technical report describes the outcomes resulting from conducting interviews with professional estimators within the electrical construction industry. The purpose of the interviews was to identify whether native files are shared, why sharing does not occur more frequently, how file sharing might benefit the estimating process, and barriers to sharing native CAD files for the purpose of estimating from CAD drawings.
Sponsorship: Electri International
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Title: LIVE LOAD FACTORS FOR CONTINUOUS GIRDER BRIDGES
Creator: Wang, Qing
Date: 2016, 2016-07
Description: Live load factors of Strength I limit state for continuous girder highway bridges are calibrated based on reliability concept adopted by...
Show moreLive load factors of Strength I limit state for continuous girder highway bridges are calibrated based on reliability concept adopted by AASHTO LRFD and LRFR specifications. A uniform reliability is maintained for multi-girder highway bridges with various span lengths. WIM data, gathered by California, Michigan, New York, Oregon, and Illinois State Department of Transportation are analyzed. Live load effects produced by WIM data are calculated using influence lines. Expected maximum live load effects in given periods are modeled and extrapolated by Gumbel distribution. A relativecalibration formula is developed in order to derive live load correction factors for designing/evaluating continuous highway bridges at a reliability level that is in consistent with simply supported highway bridges. Computer programming is conducted for data sorting and traffic statistical analysis.
Ph.D. in Civil Engineering, July 2016
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Title: INVESTIGATION OF THE RELATIONSHIP BETWEEN BID PRICE AND CLAIMS IN PUBLIC BUILDING CONSTRUCTION PROJECTS
Creator: Vuong, Huy Anh
Date: 2014, 2014-07
Description: This thesis focus on examining the relationship between bid price and claims in public construction projects in order to propose the...
Show moreThis thesis focus on examining the relationship between bid price and claims in public construction projects in order to propose the alternative bidding strategy and help owner minimize actual completion cost and gain the best value for their construction projects. The investigation on the literature of bidding methods, claims and their relationship guided us to come up with our hypotheses on building up an equation that quantitatively expressing the reverse correlation of bid price and claims. In order to archive our goal, data from 30 public construction projects were collected, and the statistic method and data analysis are utilized. Finally the equation to estimate the amount of claim from the bid price, the engineer’s estimate, and the spread between the lowest two bids are established through regression model. Even though some limitations are remained, the results from this study strongly recommend owners to prefer a contractor that offers the lowest bid and potential claim, rather than select the contractor using the traditional process of choosing the lowest bid.
M.S. in Civil Engineering, July 2014
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Title: Study of the building problems of the Badger Basket Company of Burlington, Wisconsin
Creator: Chase, Derwood
Date: 2009, 1921
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/studyofbuildingp00chas
Thesis (B.S.)--Armour Institute of Technology

Title: Stresses in riveted joints
Creator: Rook, Henry A.
Date: 2009, 1916
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/stressesinrivete00rook
Thesis (B.S.)--Armour Institute of Technology, 1916 Bibliography: leaves 39-44 B.S. in...
Show morehttp://www.archive.org/details/stressesinrivete00rook
Thesis (B.S.)--Armour Institute of Technology, 1916 Bibliography: leaves 39-44 B.S. in Civil Engineering, 1916
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Title: HEAT PUMPS IN DRINKING WATER UTILITY BUILDINGS
Creator: Colomer Pons, Ana Maria
Date: 2012-07-12, 2012-07
Description: In the United States each person consumes about 70 million BTUs per year in the residential sector, a tendency that is constantly growing...
Show moreIn the United States each person consumes about 70 million BTUs per year in the residential sector, a tendency that is constantly growing because of technology and society growth (EIA, 2011). The United States Department of Energy (USDOE, 1988) reported that heat pumps are energy efficient devices that can provide heating and cooling in residential and industrial buildings and also in households. According to Bernier (2006) heat pumps offer many advantages such as decreased space needs, higher efficiencies, and lower maintenance costs, and that is why they have been implemented in many regions throughout the United States as well as in many European countries. However, their use is many times hindered due to the high initial costs relative to conventional heating air conditioning ventilating systems (HVAC), technologies that are widely known and have been used for many years. The purpose of this thesis is to analyze the performance, economic feasibility, and greenhouse gas emission reduction of implementing heat pump devices in drinking water plants for heating and cooling needs inside the building. The proposed system is similar to groundwater heat pumps (described in an upcoming section) but instead of groundwater the heat pump relies on drinking water that has been treated in the plant and it is ready for its use. Groundwater has one main advantage because it is at a constant temperature year round (NRC, 2005) which gives the heat pump system stability in its behavior. Moreover, it is at a higher temperature than air in winter, and at a lower temperature than air in summer, which makes it an excellent candidate for heat transfer purposes in the refrigeration cycle. The four cases studies described in this work examine medium and high efficiency heat pumps installed in existing plants and new plants. Because drinking water is readily available after its treatment, the cost of drilling and grouting is avoided and this high quality water also avoids most of the problems related to quality of water such as scaling or fouling. This system gives a return of investment that is in all cases lower than six years. emissions are reduced by about 50 per cent because the use of a much more efficient device produces less for each kWh of heating or cooling delivered in the building.
M.S. in Environmental Engineering, July 2012
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Title: SEISMIC DESIGN STUDY OF STEEL PLATE SHEAR WALL
Creator: Moshiri, Ali
Date: 2012-04-20, 2012-05
Description: plate shear walls are an innovative lateral load-resisting system capable of effectively and economically bracing a building against both wind...
Show moreplate shear walls are an innovative lateral load-resisting system capable of effectively and economically bracing a building against both wind and earthquake forces. The system consists of infill steel plates connected to boundary beams and columns over the full height of the framed bay. Beam-to-column connections can be rigid or shear connections and the infill plates can be either stiffened or unstiffened, depending on the design philosophy of the infill plates. The view of some structural designers is to use heavy stiffeners to reinforce and increase the buckling capacity of shear walls, whereas, if the walls are left unstiffened and allowed to buckle, their energy absorption will increase significantly due to the post-buckling capacity. Performance of 9-story SPSW with moment resisting beam to column connections was studied under quasi-static loading condition and 10 earthquake records recorded in Los Angeles by developing a nonlinear dynamic explicit finite element models in ABAQUS. All the models were validated with experimental results. Effect of stiffness of boundary elements (VBE and HBE) and plate thickness on general behavior of the structure were also investigated. In design of SPSWs, vertical boundary elements play a major role in increasing the capacity of the system. In high seismic zones there is always a chance of plastic hinge formation in the boundary elements specially columns in any intermediate floor. It is recommended that SPSWs not be used for medium to high rise buildings in high seismic regions until the lack of capacity design requirements for this type of SPSW is rectified.
Ph.D. in Structural Engineering, May 2012
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