Civil Engineering Commons^™

Efficacy Of Geosynthetic Separators And Filters: An Evaluation Of Test Sections In Marked Tree, Arkansas, Ashique Ali Boga

Graduate Theses and Dissertations

Field and laboratory tests were conducted on 18 full-scale, geosynthetic reinforced, roadway test sections located in Marked Tree, Arkansas. Base course, geosynthetic, and subgrade samples were collected, and pavement depth, in-situ density and in-situ hydraulic conductivity measurements were obtained during a geotechnical site investigation. The performance of sections containing geotextile products being used for separation and filtration (Carthage Mills FX-66, Mirafi 570, Propex 2006, Propex 2044, and Propex 4553) was investigated.

Moisture content, sieve analysis, Atterberg limits, modified proctor, specific gravity, and hydraulic conductivity tests were performed on the acquired soil samples. Transmissivity and permittivity testing was conducted on the …

The Marked Tree Site: Evaluation Of Geosynthetic Reinforcements In Flexible Pavements, Taylor Mitchell Goldman

Graduate Theses and Dissertations

This document presents findings from a three-year, full-scale, field research project aimed at determining the benefits of using geosynthetic reinforcements to improve the performance of flexible pavements constructed over poor subgrade soils. The test site, known as the Marked Tree site, is an 850-ft (258-m) long segment of low-volume frontage road along Highway 63 in the town of Marked Tree, Arkansas. The site, constructed in 2005, consists of seventeen 50-ft (15.2-m) long flexible pavement test sections with various types of geosynthetic reinforcements (woven and nonwoven geotextiles, and geogrids), which were all positioned at the base-subgrade interface, and two different nominal …

Influence Of Recycled Asphalt Shingles On Asphalt Binder Content, Mixture Stiffness, And Laboratory Rutting Performance, Joshua David King

Graduate Theses and Dissertations

Recycled asphalt shingles (RAS) is a technology in which pavement costs can be reduced significantly and pavement properties may be enhanced. Also, incorporating shingles into pavements reduces the impacts of waste shingles in landfills, preserving our environment. However, for this new technology to be practical for implementation, a better understanding of how the ground shingles affect the properties of the asphalt is necessary. The purpose of this research was to examine the effects of recycled asphalt shingles on asphalt binder content, mixture stiffness, and laboratory rutting performance. For this project, shingles were added to hot mix asphalt mixtures at 2.5, …

Development Of A Structured Concrete Thermocline Thermal Energy Storage System, Bradley M. Brown

Graduate Theses and Dissertations

The past couple of decades have shown a concern when considering the way the world obtains its power. The focus has been switching from fossil fuels that have been used for hundreds of years to renewable energy sources, such as the sun. Solar energy is readily and infinitely available for harnessing. One problem with solar energy, though, is its inability to be used during the night time and during cloud covered weather. A solution to this problem is the use of energy storage mechanisms. For solar plants that use solar thermal energy (concentrating solar power plants), thermal energy storage (TES) …

Effects Of High-Impedance-Contrast Boundary Upon Multi-Modal Seismic Surface Wave Data, Prajwol Tamrakar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Synthetic studies and analyses of an experimental dataset were conducted to address the use of Rayleigh-type surface waves for estimation of shear wave velocity (VS) profiles of shallow bedrock sites. The shallow bedrock presents a high impedance contrast boundary which causes surface wave energy to be partitioned to higher modes. Idealized studies of hypothetical datasets and root-mean-squared calculations of error surfaces showed that if reliable dispersion data are available over a broad frequency spectrum, the VS profile can be recovered using the fundamental mode alone. However, when dispersion data are limited to a relatively narrow frequency band representing what might …

Laboratory Evaluation Of Dynamic Characterization Methods For Rapid Condition Assessment Of Bridges, Jason Kyle Herrman

Graduate Theses and Dissertations

The objective of this thesis was to devise and refine Structural Health Monitoring methods and the associated quantitative characterization methods with the specific goal of enabling rapid and reliable safety evaluations of bridges following natural or manmade hazards. Presently, the safety and serviceability of these transportation infrastructure assets for use in emergency response and recovery operations are evaluated through on-site visual inspections of individual structures by teams of specially trained engineers or technicians; a process that is manpower-intensive, subjective, and slow. Specifically, the researcher was able to identify and evaluate strategies and procedures for using dynamic testing methods to rapidly …

Regulation Issues And Prediction Of Natural Estrogen Loads For Wastewater Treatment Plants, Michelle E. Jarvie

Dissertations, Master's Theses and Master's Reports - Open

No abstract provided.

Countermeasures Against Scour At Bridge Abutments, Hua Li

Dissertations, Master's Theses and Master's Reports - Open

Scour at bridge abutments can cause damage or failure of bridges and result in excessive repairs, loss of accessibility, or even death. To mitigate abutment scour, both clear-water and live-bed laboratory experiments in a compound channel were performed using parallel walls and spur dikes as countermeasures, respectively. In addition, collars were tested under clear-water conditions only. It was found that both parallel walls and spur dikes can efficiently protect the abutment from scour provided that they are properly designed. Design guidelines were discussed for both countermeasures. Preliminary clear-water tests of collars as countermeasures against scour showed some promising results although …

Selected Chemoautotrophic Processes In Wastewater Treatment: Low Temperature Nitrification Inhibition By An Azo Dye And Biofiltration For Odor Control Of Hydrogen Sulfide, Ronald W. Martin Jr.

Dissertations, Master's Theses and Master's Reports - Open

Biochemical processes by chemoautotrophs such as nitrifiers and sulfide and iron oxidizers are used extensively in wastewater treatment. The research described in this dissertation involved the study of two selected biological processes utilized in wastewater treatment mediated by chemoautotrophic bacteria: nitrification (biological removal of ammonia and nitrogen) and hydrogen sulfide (H2S) removal from odorous air using biofiltration.

A municipal wastewater treatment plant (WWTP) receiving industrial dyeing discharge containing the azo dye, acid black 1 (AB1) failed to meet discharge limits, especially during the winter. Dyeing discharge mixed with domestic sewage was fed to sequencing batch reactors at 22oC and 7oC. …

An Empirical Investigation On The Impacts Of Ground-Level Ozone Concentrations On National Ambient Air Quality Standards: The Case Of Lake Charles, Louisiana, Benedict Nweke Nwokolo

Doctoral Dissertations

This study presents information upon which the state of Louisiana can base its ozone State Implementation Plans (SIPs) designed to achieve planned emissions reduction that are required by the Clean Air Act (CAAA) of 1990. The research investigation included an assessment survey on a number of Transportation Control Measures (TCMs) and their degree of acceptability by the residents of Lake Charles area of Louisiana, the research target area. The TCMS were first ranked on the basis of people's perception of each TCM and four TCMs were later analyzed for cost-effectiveness using computer mathematical models. The Traffic Flow Improvements TCM was …

The Effect Of Pipe Bursting On Nearby Utilities, Pavement, And Structures, Alan Atalah

Doctoral Dissertations

This dissertation has involved field and analytical studies of ground movements, ground vibrations and other design issues associated with trenchless pipe replacement (or pipe bursting, as it is commonly known). The process is used to replace an existing underground service pipe with a completely new pipe but without the disturbance and cost of excavating a trench from the surface. The process typically involves the insertion of a tool into the existing pipe that has a maximum diameter that is slightly larger than the existing pipe. This tool is used to break the existing pipe into pieces and to displace the …