Search results
(61 - 80 of 218)
Pages
- Title
- Improvement of Sheridan road in Glencoe
- Creator
- Walther, Ralph A., Dawson, M., Sturtevant, R. W.
- Date
- 2009, 1909
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/improvementofshe00walt
Thesis (B.S.)--Armour Institute of Technology
- Title
- FATIGUE, FRACTURE, AND CRACK GROWTH BEHAVIOR OF FIVE CANDIDATE STEELS FOR WIND TOWER APPLICATION
- Creator
- Tsosie, Henrietta R.
- Date
- 2011-08, 2011-07
- Description
-
Fatigue, fracture toughness, and crack propagation tests were performed on five candidate steels for wind tower applications. Normally, these...
Show moreFatigue, fracture toughness, and crack propagation tests were performed on five candidate steels for wind tower applications. Normally, these steels are ordered to meet ASTM A572/A709 Grade 50 or EN 10025-2 Grade S355 in the normalized condition. Five steels with varying carbon content and alloy additions focusing on niobium and vanadium content are investigated. Two of the five steels are in the normalized condition to check the EN 10025-2 requirement while the rest are in the as-rolled condition. Fatigue tests were performed to determine the endurance limit using a constant amplitude loading at a constant load ratio. Fracture toughness testing using the J integral method was performed to determine the critical fracture energy, Jc. This value is then converted to the critical plain strain stress intensity factor if requirements are met. Three fracture toughness tests were performed for each material at room temperature using a C(T) specimen. Crack propagation tests were performed to determine the Paris constants using a contoured double cantilever beam specimen. The steels with niobium give better results in fatigue and displayed smaller grain diameters than the steels with vanadium. The fatigue results for the low carbon steel with niobium are comparable to another HPS steel. Overall, the low carbon steel with niobium provides better toughness, fatigue resistance, and weldability than the steels that are normalized to meet the EN 10025-2 requirement for wind tower plates.
M.S. in Materials Science and Engineering, July 2011
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- Title
- Impounding dam and filtration plant
- Creator
- Nelson, Chas. J, Tompkins, G. Dwight
- Date
- 2009, 1907
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/impoundingdamfil00nels
Thesis (B.S.)--Armour Institute of Technology, 1907 B.S. in Civil Engineering, 1907
- 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
Show less
- 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
- Mechanical filtration for municipal water supply
- Creator
- Spalding, R. S.
- Date
- 2009, 1906
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/mechanicalfiltra00spal
Thesis (B.S.)--Armour Institute of Technology
- Title
- Method of measuring earth pressures on vertical and inclined retaining walls
- Creator
- Fainstein, Morris
- Date
- 2009, 1920
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/methodofmeasurin00fain
Thesis (B.S.)--Armour Institute of Technology
- Title
- A history of the development of the suspension bridge
- Creator
- Mann, Herbert A
- Date
- 2009, 1921
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/historyofdevelop00mann
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaves 86-98
- Title
- An investigation of the effects of heat treatment upon some of the physical properties of two chrome-vanadium steels
- Creator
- Rothwell, Richard F
- Date
- 2009, 1913
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/investigationofe00roth
Thesis (B.S.)--Armour Institute of Technology; Bibliography: leaf 24
- 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
- Location of the Overton County railroad
- Creator
- Pratt, Edmund A.
- Date
- 2009, 1907
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/locationofoverto00prat
Thesis (B.S.)--Armour Institute of Technology, 1907 B.S. in Civil Engineering, 1907
- 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
- Investigation of the actual stresses in stirrups of reinforced concrete T-beams
- Creator
- Nitka, J., Senescall, C., Peterson, H., Weiss, L.
- Date
- 2009, 1918
- Publisher
- Armour Institute of Technology
- Description
-
http://www.archive.org/details/investigationofa00nitk
Thesis (B.S.)--Armour Institute of Technology;Bibliography : leaf 97
- 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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