Selective Catalytic Reduction Of Nitric Oxide Over Cerium-Doped Activated Carbons,
2012
University of Texas at Arlington
Selective Catalytic Reduction Of Nitric Oxide Over Cerium-Doped Activated Carbons, Annaprabha Athappan
Civil Engineering Dissertations - Archive
Selective catalytic reduction (SCR) with ammonia for diesel engine NOx reduction using activated carbon (AC) was studied. Comparisons of unmodified and cerium-doped Granular Activated Carbon (GAC), Activated Carbon Fiber (ACF), and Multiwall Carbon Nanotubes (MWCNTs) were conducted. Physical and chemical properties and durability of the catalysts were examined using Scanning Electron Microscope (SEM), Energy Dispersive Spectroscopy (EDS), carbon hydrogen and nitrogen (CHN) analysis, X-ray Diffraction (XRD) analysis, Raman spectroscopy, X-ray Photoelectron spectroscopy (XPS), Thermo gravimetric analysis (TGA), Braunauer-Emmett-Teller (BET) surface area analysis and density analysis. Experiments were carried in a fixed bed column at various temperatures from 100º to 400º …
Visualising Urban Flooding Scenarios Using Video Game Technology,
2012
Department of Computing, Cork Institute of Technology, Cork, Ireland.
Visualising Urban Flooding Scenarios Using Video Game Technology, William Elliott Lynn
Theses
This thesis investigates the application of computer graphics to the visualisation of urban flooding scenarios. The demand for urban flooding visualisations is presented in the context of an EU wide climate change response strategy. An analysis of the requirements from various stakeholders is presented and a strategy that addresses these requirements is synthesised. A study on the appropriate computer graphics methods and technologies is outlined and limitations of current technologies are assessed. Systems that solve these limitations are described and the result of usability and user acceptance testing are offered as evidence.
Interfacing Building Response With Human Behavior Under Seismic Events,
2012
Johns Hopkins University
Interfacing Building Response With Human Behavior Under Seismic Events, Z. Liu, Mehdi Jalalpour, C. Jacques, S. Szyniszewski, J. Mitrani-Reiser, James K. Guest, T. Igusa, B. W. Schafer
Civil and Environmental Engineering Faculty Publications
The goal of this paper is to model the interaction of humans with their built environment during and immediately following a natural disaster. The study uses finite element simulations to evaluate the response of buildings under input ground motions and agent-based dynamic modeling to model the subsequent evacuation of building occupants in the study area immediately following the seismic event. The structural model directly captures building damage and collapse, as well as floor accelerations and displacements to determine nonstructural damage, injuries and fatalities. The goal of this research is to make connections between building damage and occupant injuries, with geographic …
Performance Of Prestressed Concrete Cylinder Pipe (Pccp) In Water Applilcations,
2012
University of Texas at Arlington
Performance Of Prestressed Concrete Cylinder Pipe (Pccp) In Water Applilcations, Rahul Manda
Civil Engineering Theses - Archive
The analysis of water pipes failure data is of great importance as it has a significant impact society and the environment. These failures also have the overall impact on the financial burden on the water industry. This thesis evaluates the failure rate of Prestressed Concrete Cylinder Pipe (PCCP), which is one of the most conventional rigid pipes and are extensively used as the water and wastewater pipeline in the US and around the world. A statistical analysis of the failure rate based on the diameter size over multiple years will help in determining the performance of PCCP pipes. Also, the …
Effects Of Fiber Reinforced Polymer (Frp) Wrap On Reducing Chloride Penetration In Concrete,
2012
University of Texas at Arlington
Effects Of Fiber Reinforced Polymer (Frp) Wrap On Reducing Chloride Penetration In Concrete, Gunther G. Garcia
Civil Engineering Theses - Archive
The objective of this study was to investigate the effects of FRP wrap on reducing chloride penetration in concrete. It has been established that FRP wrap used to retrofit concrete structures offer a high resistance to chemical solutions. The ACI 318-11 Code allows for a reduction of clear cover depth if an equivalent clear cover depth can be establish. The FRP material used herein consisted of Tyfo SCH-41 and Tyfo SEH-51A composites fabricated from carbon and glass fibers, respectively. The wrapped FRP concrete specimens and control specimens without FRP wrap were tested according to ASTM C 1543 and ASTM C …
Determining The Effectiveness Of Chlorine-Based Biofilm Control On The Friction Factors Of Large Diameter Pipelines In Raw Water,
2012
University of Texas at Arlington
Determining The Effectiveness Of Chlorine-Based Biofilm Control On The Friction Factors Of Large Diameter Pipelines In Raw Water, Shelly Stamler Hattan
Civil Engineering Theses - Archive
Large diameter transmission mains pumping raw water experience capacity loss during the summer months due to the growth of biofilm. The loss of capacity impacts power costs at a time when power is obtained at a premium. Biofilm growth varies with the seasons and varies along the length of the pipeline. Biofilm growth and decay directly impacts the friction factors. Future design work should consider a seasonal friction factor rather than an aged friction factor over time.The method of controlling biofilm is with the application of chloramines at the lake pump stations. This study compares the difference between little to …
Water Permeability In Fiber Reinforced Plastic (Fpr)-Wrapped Concrete,
2012
University of Texas at Arlington
Water Permeability In Fiber Reinforced Plastic (Fpr)-Wrapped Concrete, Jyoti Ojha
Civil Engineering Theses - Archive
A finite element analysis is performed using ANSYS software to analyze progress of water and its circulation in FRP wrapped concrete. This paper presents the modeling of water diffusion in FRP. Finite element programs do not usually employ issue permeability or diffusion. Therefore, diffusion of water in FRP is modeled by analogy with thermal conduction. A brief description of theoretical background is presented in the paper. The recommended FE modeling procedures are listed. Diffusion coefficient of Tyfo SCH 41S-1 obtained from an inspection report is used to analyze water permeably of FRP. Tyfo SCH 41S-1 is the most popular FRP …
Resilient Moduli Properties Of Compacted Unsaturated Subgrade Materials,
2012
University of Texas at Arlington
Resilient Moduli Properties Of Compacted Unsaturated Subgrade Materials, Pinit Ruttanaporamakul
Civil Engineering Theses - Archive
According to the new Mechanistic Empirical Pavement Design Guide (MEPDG) and 1993 AASHTO flexible pavement design guide, Resilient Modulus (MR) has been used extensively as an important material property in structure design of pavement. The modulus is used as the primary input parameter to determine the stiffness parameters and constitutive behavior of pavement components. The system of pavement basically consists of the layers of surface, base, subbase (optional), and subgrade. The compacted subgrade soils supporting pavement structure are typically unsaturated with degrees of saturation varying from 75 to 90%. The effect of unsaturated soil behavior on the mechanical properties of …
Productivity Analysis Of Box Jacking,
2012
University of Texas at Arlington
Productivity Analysis Of Box Jacking, Hossein Tavakoli
Civil Engineering Theses - Archive
Trenchless Technology (TT) offers methods to install utilities through the ground without damaging the surface. Box Jacking is a trenchless method for installation of prefabricated box and drainage structures without digging a trench. The concept of box jacking is similar to pipe jacking operations by first excavating an entry shaft, building the thrust block and concrete base, and setting jacking equipment. The process starts with pushing boxes while excavating at face, however, the movement of each box is achieved each time excavation at the shield is completed. Additionally, a pilot tube might be required in advance of box jacking operations. …
Assessment And Rating Of Mechanically Stabilized Earth Walls,
2012
University of Texas at Arlington
Assessment And Rating Of Mechanically Stabilized Earth Walls, Noel Janacek
Civil Engineering Theses - Archive
Mechanically stabilized earth (MSE) walls have been increasingly utilized in the United States since 1972 and in Texas since 1979. MSE walls provide earth retention for commercial, industrial and transportation projects throughout Texas. Within the transportation industry, the traditional design life of MSE walls is 75 years, with new projects requiring 100 year design life. The millions of square feet of existing MSE walls are generally less than half of the anticipated design life, making identifying and assessing the existing wall inventory a significant asset management component for optimizing maintenance expenditures. This thesis proposes and applies a system that assesses …
Resilient Properties Of Unsaturated Base Materials,
2012
University of Texas at Arlington
Resilient Properties Of Unsaturated Base Materials, Ranjan Kumar Rout
Civil Engineering Theses - Archive
A pavement system basically consists of a surface layer, a base course, a subbase (optional) and the subgrade. As per MEPDG and 1993 AASHTO flexible pavement design guide Resilient Modulus (MR) is used as the primary input parameter to determine the stiffness parameters and the constitutive behavior of pavement components, such as subgrade and unbound bases. Generally, pavements are constructed on compacted soils that are typically unsaturated with degrees of saturation varying from 75 to 90%. The main focus of this research is to determine the effect of matric suction on the resilient moduli property of the base materials. The …
Design Of Controlled Low Strength Material For Bedding And Backfilling Using High Plasticity Clay,
2012
University of Texas at Arlington
Design Of Controlled Low Strength Material For Bedding And Backfilling Using High Plasticity Clay, Anil Kumar Raavi
Civil Engineering Theses - Archive
Flowable fill or Controlled Low Strength Material (CLSM) is a self-compacted cementitious material used in the field in the place of compacted fill. It is also known as unshrinkable fill, controlled density fill, flowable mortar, plastic-soil cement, soil-cement slurry, and others. The advantages of this material include lesser soil settlements, elimination of compaction, and lower costs when compared to chemically treated and compacted subsoils. CLSMs have a wide range of applications such as using them as a backfill, bedding material, trench filling material, void filling material, bridge abutment and embankment materials and also in pavement bases. Current research is aimed …
Selecting A Shaft/Pit Construction Method For Trenchless Technology,
2012
University of Texas at Arlington
Selecting A Shaft/Pit Construction Method For Trenchless Technology, Bassam Abusad
Civil Engineering Theses - Archive
The word shaft describes a vertical access point that is created by excavating, vertical boring, or blasting required before the start of tunneling or boring operations. Most trenchless technologies require entry shafts and exit shafts and in some cases and intermediate shaft Trenchless technologies are methods used for the construction and rehabilitation of underground utility pipes. Since pits and shafts are excavated below the ground surface level, Occupational Safety and Health Administration (OSHA) rules and regulations are enforced for the safety of the workers. The focus of this research is to describe shaft and pit construction methods as applied to …
Comparison Of Measured And Predicted Response Of Six Mnroad Asphalt Test Sections,
2012
University of Texas at Arlington
Comparison Of Measured And Predicted Response Of Six Mnroad Asphalt Test Sections, Veni Valli Nagarajan
Civil Engineering Theses - Archive
The study, sponsored by MnRoad, aimed to compare the measured and predicted values of strains and stresses for six cells 33, 34, 35, 77, 78 and 79 of the third MnRoad experiments. Cells 33, 34 and 35 were constructed for studying the polyphosphoric acid study while cells 77, 78 and 79 for the fly-ash stabilization study, during 2007. Each cell is instrumented with three transverse strain gauges and three longitudinal strain gauges at the bottom of HMA layer while three pressure cells were located at the top of the subgrade layer to measure vertical compressive stress.The FWD deflection data collected …
Financial Evaluation Of Milege Based User Fees For Florida's Transportation Funding,
2012
University of Central Florida
Financial Evaluation Of Milege Based User Fees For Florida's Transportation Funding, Massoud Moradi
Electronic Theses and Dissertations
Motor fuel taxes have been collected as a principal source of highway funding for close to a century. They account for approximately two thirds of all the highway user fees and about half of all highway expenditures. Federal fuel taxes have not kept pace with the inflation in general and increasing traffic demand and resulting construction, maintenance and operation costs of the transportation assets in particular. Lack of political will, combined with rising anti-tax sentiment among the populace, has kept the federal tax level not only well below its initial intents, but also at a unsustainable level in future. Mileage …
Land Use Effects On Energy And Water Balance-Developing A Land Use Adapted Drought Index,
2012
University of Central Florida
Land Use Effects On Energy And Water Balance-Developing A Land Use Adapted Drought Index, Chi Han Cheng
Electronic Theses and Dissertations
Climate change is expected to increase the frequency, intensity and duration of droughts in all parts of the United States (US). Snow packs are disappearing earlier in the spring and summer, with reduced stream-flow. Lower reservoir levels, higher temperatures, and greater precipitation variability have been observed. Drought events in the US have threatened drinking water supplies for communities in Maryland and Chesapeake Bay as observed in 2001 through September 2002; Lake Mead in Las Vegas in 2000 through 2004; Peace River and Lake Okeechobee in South Florida in 2006; and Lake Lanier in Atlanta, Georgia in 2007. ENSO influences the …
Resilience Of Bridges Following Aftershocks,
2012
University of Central Florida
Resilience Of Bridges Following Aftershocks, Diego Francisco Espinosa
Electronic Theses and Dissertations
The ability to predict the reduction in capacity of a structure after an earthquake is vital in the process of assessing a structure after a main-shock or an after-shock. Main-shocks are normally followed by a few aftershocks in a short period of time. Researchers in the past have focused for the most part on the effects of main-shocks on buildings. Very little research has been performed on the ability to predict the reduction in capacity of bridges in aftershocks. This thesis focuses on providing a way of assessing the reduction in capacity for main-shocks as compared to aftershocks and the …
Performance Of Mechanical And Non-Mechanical Connections To Gfrp Components,
2012
University of Central Florida
Performance Of Mechanical And Non-Mechanical Connections To Gfrp Components, Nnadozie N. Dike
Electronic Theses and Dissertations
There are presently many solutions to dealing with aging or deteriorated structures. Depending on the state of the structure, it may need to be completely over-hauled, demolished and replaced, or only specific components may need rehabilitation. In the case of bridges, rehabilitation and maintenance of the decks are critical needs for infrastructure management. Viable rehabilitation options include replacement of decks with aluminum extrusions, hybrid composite and sandwich systems, precast reinforced concrete systems, or the use of pultruded fiber-reinforced polymer (FRP) shapes. Previous research using pultruded glass fiber-reinforced polymer (GFRP) decks, focused on behaviour under various strength and serviceability loading conditions. …
Macroscopic Crash Analysis And Its Implications For Transportation Safety Planning,
2012
University of Central Florida
Macroscopic Crash Analysis And Its Implications For Transportation Safety Planning, Chowdhury Kawsar Siddiqui
Electronic Theses and Dissertations
Incorporating safety into the transportation planning stage, which is often termed as transportation safety planning (TSP), relies on the vital interplay between zone characteristics and zonal traffic crashes. Although a few safety studies had made some effort towards integrating safety and planning, several unresolved problems and a complete framework of TSP are still absent in the literature. This research aims at examining the suitability of the current traffic-related zoning planning process in a new suggested planning method which incorporates safety measures. In order to accomplish this broader research goal, the study defined its research objectives in the following directions towards …
Multi-Level Safety Performance Functions For High Speed Facilities,
2012
University of Central Florida
Multi-Level Safety Performance Functions For High Speed Facilities, Mohamed Ahmed
Electronic Theses and Dissertations
High speed facilities are considered the backbone of any successful transportation system; Interstates, freeways, and expressways carry the majority of daily trips on the transportation network. Although these types of roads are relatively considered the safest among other types of roads, they still experience many crashes, many of which are severe, which not only affect human lives but also can have tremendous economical and social impacts. These facts signify the necessity of enhancing the safety of these high speed facilities to ensure better and efficient operation. Safety problems could be assessed through several approaches that can help in mitigating the …
