Civil Engineering Commons^™

Rational Best-Value Model Based On Expected Performance, Magdy Abdelrahman, Tarek Zayed, Jay Hietpas, Ahmed Elwakil

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The best-value procurement strategy is gaining the interest of federal and state agencies. The strategy increases the value added to a project for each dollar added. A new concept of best value, that is, a rational and flexible model based on expected performance, is presented. The model's flexibility is obvious in the selection of parameters to be included in the contractor selection process and in the determination of their weights. The model's rationality will be achieved through relating all awarded scores to the agency's expected performance. The establishment of the best-value model relies on the past record of the contractor's …

Studies On Field Stabilization Methods To Prevent Surficial Slope Failures Of Earth Fill Dams, Venkata S. Dronamraju

Civil Engineering Dissertations - Archive

Surficial failures are occurring frequently on the slopes of earthfill dams which are predominantly rainfall induced. Desiccation cracks form on the slope surface during dry environment which accelerates infiltration during rainfall. Infiltration causes increase of pore water pressures and saturation of soil mass in top layer resulting in surficial failures. Numerous surficial failures occurred on the slope of earthfill dams maintained by The United States Army Corps. of Engineers. The current research is undertaken at the University of Texas at Arlington with an objective of exploring the best field stabilization method to mitigate these surficial failures.Two sites, Joe Pool Dam …

Development Of Ballistic Limit Equations For Dual-Wall Spacecraft Shielding: A Concise History And Suggestions For Future Development, William P. Schonberg

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

All earth-orbiting spacecraft are susceptible to impacts by orbital debris particles, which can occur at extremely high speeds and can damage flight- and mission-critical systems. The traditional damage mitigating shield design for this threat consists of a “bumper” that is placed at a relatively small distance away from the main “inner wall” of the spacecraft. The performance of a hypervelocity impact shield is typically characterized by its ballistic limit equation, which is typically drawn as a line of demarcation between regions of rear-wall perforation and no perforation; when graphically represented, it is often referred to as a ballistic limit curve. …

Implications Of Future Heavier Trucks For Europe's Bridges, Colin C. Caprani, Bernard Enright, Eugene O'Brien

Conference papers

European road freight transport has increased by 38% between 1995 and 2005 and this strong growth trajectory seems likely to continue into the future. To address this growth without compromising the competitativeness of European transport, some countries are contemplating the introduction of longer and heavier trucks, with up to 8 axles and gross weights of up to 60 t. This has the advantage of reducing the number of vehicles for a given volume or mass of freights, reducing labour, fuel and other costs. However, many roads authorities are concerned about the implications for Europe's bridge infrastructure. For bridge loading, it …

Pavement Quality Indicators Study, Wayne Jensen Ph.D., Cody Kluver

Mid-America Transportation Center: Final Reports and Technical Briefs

The Nebraska Department of Roads (NDOR) conducts annual examinations of the Nebraska’s interstate and federal high-way pavements. During these examinations, numerous indicators of pavement quality are measured directly or are com-piled from parameters recorded by a vehicle passing over the pavement section. Parameters are documented and analyzed for each one-tenth mile segment. A number of pavement sections where innovative features have been incorporated were selected by the NDOR for comparison to nearby conventional pavement sections. This study used data recorded by the NDOR as well as field observations to develop a comparison between two pavement sections, one with innovative fea-tures …

Quantifying Anisotropy In Asphalt Concrete Pavements Using An Ultrasonic Method, Monica C. Jurado

Open Access Theses & Dissertations

Asphalt concrete is a bonded granular material whose internal structure is anisotropic. Such anisotropy is due to anisotropic particles and void's structure, particle distribution and orientation, and restrain and force pattern used during compaction. Even with this knowledge asphalt concrete design is made considering asphalt concrete as an isotropic material. The biggest difference between an isotropic and anisotropic material is that, an isotropic material is characterized by two independent constants and an anisotropic material could be characterized by up to 81 constants. An extensive research to characterize and quantify anisotropy is only available for some composite materials. Based on the …

Expert System Design Guide For Lower Classification Roads Over High Pi Clays, Yaqi Wanyan

Open Access Theses & Dissertations

This research was focused on low-volume roads over expansive clayey soils in Texas. In spite of the redundant pavement designs recommended and widely used in Texas for roads in high PI clay areas, these pavements often fail prematurely. This failure occurs primarily because of the highly variable properties of the clayey subgrade throughout the year due to moisture fluctuations. The problematic nature of high PI clays, despite the fact that volumetric changes such as heaving are sometime considered in the design, is of concern since they contribute to roughness and longitudinal shrinkage cracking of the road, and as such the …

Alternatives To Fuel Tax: A State Level Perspective, Jungeun (Jen) Oh, Kumares C. Sinha

JTRP Technical Reports

Under the current fuel-tax-based highway financing system, the funding gap between highway needs and revenue available is expected to grow as vehicle fuel economy improves and use of alternative fuels increases. Consequently, the highway financing mechanism needs to be restructured or a different financing strategy undertaken. Previous research provided examples of successful implementation of pricing schemes in terms of design of pricing scheme, technology issues, legal and institutional issues, and public acceptability. Synthesizing this information, a methodological framework was established for evaluation of alternative user charging schemes. Based on the assessment of the current and projected highway revenue and the …

Post-Construction Evaluation Of Lime-Treated Soils, Chulmin Jung, Antonio Bobet

JTRP Technical Reports

Lime is used to treat weak subgrade soils during construction of highways. A small amount of lime (4 to 7%) is used to rapidly dehydrate and modify fine grained soils. The modification process improves workability and compactability of the soils. Although the lime modification process is primarily aimed at construction expediency, additional effects such as long-term improvement of stiffness and/or strength by pozzolanic and carbonation cementation reactions are expected. Lime treatment has been employed in Indiana over several decades, but the long-term performance of lime-treated soils has not been well quantified and no field tests have been done on roads …

Hurricane Evacuation: Origin, Route And Destination, Vinayak Dixit

Electronic Theses and Dissertations

Recent natural disasters have highlighted the need to evacuate people as quickly as possible. During hurricane Rita in 2005, people were stuck in queue buildups and large scale congestions, due to improper use of capacity, planning and inadequate response to vehicle breakdown, flooding and accidents. Every minute is precious in situation of such disaster scenarios. Understanding evacuation demand loading is an essential part of any evacuation planning. One of the factors often understood to effect evacuation, but not modeled has been the effect of a previous hurricane. This has also been termed as the 'Katrina Effect', where, due to the …

Characteristics Of Red Light Running Crashesin Florida, Dina Elnashar

Electronic Theses and Dissertations

Red light running is one of the main contributing factors of crashes in urban areas in Florida and the United States. Nationwide, according to preliminary estimates by the Federal Highway Administration (FHWA) 2001, there were nearly 218,000 red-light running crashes at intersections. These crashes resulted in as many as 181,000 injuries and 880 fatalities, and an economic loss estimated at $14 billion per year nationwide, According to the Community Traffic Safety Team Florida Coalition (A statewide traffic safety group) there were 9,348 crashes involving red-light running in Florida and 127 fatalities in 1999. This research study focused on studying the …

The Calibration And Verification Of Simulation Models For Toll Plazas, Christopher Russo

Electronic Theses and Dissertations

A great deal of research has been conducted on Central Florida toll roads to better understand the characteristics of the tolling operation. In this thesis, the development and calibration of a toll plaza simulation models will be analyzed using two simulation programs varying mostly in their modeling theory. The two models utilized are, SHAKER, a deterministic queuing model for vehicles utilizing toll collection facilities, and VISSIM, a globally popular stochastic simulation software. The benefits of simulation models leads to the purpose of this thesis, which is to examine the effectiveness of two toll modeling programs that are similar in purpose …

Evaluation Of Climatic And Ecohydrological Effects On Longwave Radiation And Evapotranspiration, Maria Rizou

Electronic Theses and Dissertations

Modern tools, nontraditional datasets and a better understanding of the interaction between climate and ecohydrology are continuously being developed as today's society is in critical need for improving water management, predicting hydrometeorological hazards and forecasting future climate. In particular, the study of the intra- and inter-annual variations in grass productivity and evapotranspiration caused by variations in precipitation/soil moisture and other biophysical factors is of great significance due to their relation to future climatic changes. The research presented here falls in three parts. In the first part of the dissertation, a land use adaptable model, based on the superposition of the …

Impact Of Construction On Freeway Traffic Operations, Seema Jagtap

Electronic Theses and Dissertations

This study provides an insight into the impact of construction activities on traffic operations. Specifically, the topic of interest for this thesis is to study the impact of construction on traffic operations for construction projects on Interstate 4 from SR 434 to John Young Parkway, from SR 528 to SR 535, and from SR 482 to SR 528. These three projects were chosen because they were the only projects on Interstate 4 where both construction data and loop detector data were available for analysis. The data was collected by examining the Florida Department of Transportation daily inspection reports which had …

Development Of Hydraulic And Soil Properties For Soil Amendments And Native Soils For Retention Ponds In Marion County, Florida, Lisa Naujock

Electronic Theses and Dissertations

The vadose zone plays an important role in managing stormwater. Predicting the water balance and water movement is crucial in ground water remediation to keep water suitable for use. To aid in understanding soils ability to transmit and store water, soil and hydraulic properties were analyzed for soils in Marion County, Florida, and potential soil amendments. Soil and hydraulic properties were examined for two soil amendments and for the soils in Marion County, Florida, at the South Oak and the Hunter's Trace locations. The hydraulic properties measured were the soil moisture retention curve (SMRC) and saturated hydraulic conductivity (Ks). The …

Severity Analysis Of Driver Crash Involvements On Multilane High Speed Arterial Corridors, Alexis Nevarez-Pagan

Electronic Theses and Dissertations

Arterial roads constitute the majority of the centerline miles of the Florida State Highway System. Severe injury involvements on these roads account for a quarter of the total severe injuries reported statewide. This research focuses on driver injury severity analysis of statewide multilane high speed arterials using crash data for the years 2002 to 2004. The first goal is to test different ways of analyzing crash data (by road entity and crash types) and find the best method of driver injury severity analysis. A second goal is to find driver, vehicle, road and environment related factors that contribute to severe …

Finite Element Modeling Of Tides And Currents Of The Pascagoula River, Qing Wang

Electronic Theses and Dissertations

This thesis focuses on the simulation of astronomic tides of the Pascagoula River. The work is comprised of five steps: 1) Production of a digital elevation model describing the entire Pascagoula River system; 2) Development of an inlet-based, unstructured mesh for inbank flow to better understand the basis of the hydrodynamics within the Pascagoula riverine system. In order to assist in the mesh development, a toolbox was constructed to implement one-dimensional river cross sections into the two-dimensional model; 3) Implementation of a sensitivity analysis of the Pascagoula River two inlet system to examine the inlet effects on tidal propagation; 4) …

Sediment Budgets In The Irish Estuarine Environment, Kevin Motherway

Theses

A sediment budget is the quantification of sediment sources and sinks for natural physical systems such as rivers and estuaries.

This thesis has developed estuarine sediment budgets for Cork Harbour, Kinsale Harbour and Youghal Harbour. The thesis includes a literature review of the properties of sediment, river and estuary related sediment transport, sediment management and sediment related legislation and the approaches used to develop a sediment budget for an estuary system.

An extensive study of riverine suspended sediments discharging to the estuaries has been undertaken. Both surface grab samples and depth integrating suspended sediment samples were collected, tested and analysed. …

Novel Stabilization Methods For Sulfate And Non-Sulfate Soils, Chakkrit Sirivitmaitrie

Civil Engineering Dissertations - Archive

Expansive soils are commonly found in arid and semi-arid climate zone. These soils typically exhibit moderate to high plasticity, low to moderate strength, and high swell and shrinkage characteristic which in turn result in more swelling problems when the soil absorbs water. Both low strength characteristic and volumetric movements weaken the subgrade soils that they may lead to structural distress on road pavements. This research project was conducted at the City of Arlington, Texas. Soils in Arlington are known to be highly expansive. The expansive soils consist of both sulfate-rich soils and non-sulfate soils. This research project was conducted to …

Coupling The Hydrodynamic And Water Quality Model Ce-Qual-W2 With A Multi-Trophic Fish Bio-Energetics Model For Lake Roosevelt, Washington, Michael Lee Mckillip

Dissertations and Theses

Grand Coulee Dam created Franklin D. Roosevelt Lake as part of the Columbia Basin Project. Located in northeastern Washington State, the Project provides economically important hydropower (19 billion kilowatt hours per year), irrigation (225,000 ha), flood control, and sport fishing ($5 to 20 million annually). A good system understanding aids in balancing these beneficial uses for the 230 km long reservoir. The reservoir's atypical 45-day mean residence time is much shorter than a typical lake, and much longer than for a riverine dam. The spring freshet requires drawdowns of 15 to 20 m for flood control—the driving characteristic of reservoir …

A Laboratory Study Of Struvite Precipitation For Phosphorus Removal From Concentrated Animal Feeding Operation Wastewater, Sushmita Dhakal

Masters Theses

"Struvite precipitation occurs spontaneously in many wastewater treatment facilities as a nuisance. However, struvite precipitation is now being studied as a method to concurrently treat high phosphorus wastewaters and generate a valuable product. Many factors influence the precipitation of struvite such as component -ion molar ratios, pH, aeration, solubility, solids and mixing energy. In the present work, struvite precipitation in the actual swine wastewater was studied by strategically controlling aeration, pH, and mixing"--Abstract, page iv.

Performance Of Fire-Damaged Prestressed Concrete Bridges, Wendy Leann Moore

Masters Theses

"The purpose of this experimental program was to develop and analyze the effects of fire damage on prestressed concrete bridges. Flexural strength and serviceability of the bridge were measured by inputting fire damaged data into a parametric study spreadsheet consisting of a typical 3-span continuous prestressed concrete bridge. Data was obtained by exposing two types of specimens to different levels of elevated temperatures and then cooling them at room temperature to simulate fire damage. The two specimen types were prestressing strands which were tested in tension and concrete blocks with a single prestressing strand embedded in the center, which were …

Hazards Assessment Of St. Charles County - Earthquakes And Floods, Amy Lynn Krauch

Masters Theses

"Located on the northernmost limits of the St. Louis metropolitan area, St. Charles County has been, and continues to be, one of the fastest-growing counties in the country. The county consists of several major cities featuring extensive industry, retail, and agriculture. Bounded by the Missouri River on the south and the Mississippi River on the north and east, St. Charles County is predominantly flat, low-lying terrain at great risk to periodic flooding. The county is also well within the area of influence for several local seismic zones, increasing the susceptibility to earthquake damage. Given the apparent risk to both flood …

Laboratory Analysis Of Small Strain Moduli In Compacted Silts, David M. Weidinger

Masters Theses

"Soil compaction quality control accounts for a significant portion of geotechnical practice. Often the performance of a roadway can be directly linked to the quality of the compacted subgrade. A poor subgrade can result in weak areas in the road causing excessive deflections at the surface, ultimately leading to a pot hole or uneven surface and an unpleasant ride for the travelers. Vehicles passing over a section of highway causes small strains in the founding soil. These strains accumulate over time. A better understanding of how the compacted soil responds at small strains could shed light on improving the quality …

Experimental Validation Of An Integrated Frp And Visco-Elastic Hardening, Damping, And Wave-Modulating System For Blast Resistance Enhancement Of Rc Columns, Brian Henry Wood

Masters Theses

"In today's society, terrorist attacks and accidental explosions pose a major threat to critical infrastructure. Vulnerable to blast loading, structures must be rehabilitated to ensure structural stability and protect human life. The goal of this study is to develop and validate a sandwich composite technology for column retrofitting. The new technology consists of an inner fiber reinforced polymer (FRP) sheet, an outer FRP sheet, and a visco-elastic (VE) layer sandwiched between the two FRP sheets. The inner FRP sheet is wrapped around an existing column for confinement, while the outer FRP sheet is for anchoring of the VE layer into …

Electromagnetic Modeling Of Distributed Coaxial Cable Crack Sensors In Reinforced Concrete Members, Mei Wang

Masters Theses

"Distributed crack sensors were recently developed with coaxial cables that are composed of inner and outer conductors as well as dielectric layer in between. These sensors were designed based on the change in topology of the cable outer conductor structure under strain effects. Various tests of reinforced concrete (RC) beams and columns indicated that the newly designed sensors are 10~50 times more sensitive than commercial cables to the longitudinal elongation applied on their cable structures. The spatial resolution of the sensors is approximately 50 mm. Limited numerical simulations with the transmission line theory and the finite difference time domain model …

Development Of A Gis-Based Seismic Hazard Screening Tool, Andrew J. Wilding

Masters Theses

"Geotechnical earthquake engineering hazards have consequences that are difficult to mitigate, especially for infrastructure systems with multiple and distributed components. In the last few decades significant progress has been made to provide more accurate and useful methods to evaluate hazards for complex systems. One of these advances involves the application of spatial analysis and geographic information systems (GIS), for not only presenting data as maps, but also providing more practical and usable solutions, such as calculating the hazard potential with spatial distribution. This thesis studies the evaluation of geotechnical earthquake engineering hazards within a GIS environment, using borehole-specific data and …

Behavior Of Full-Scale Rc T-Beams Strengthened In Shear With Externally Bonded Frp Sheets, Antonio Brancaccio

Masters Theses

"Shear deficiencies in many bridges may be considered even more critical than flexural deficiencies since shear failures occur without advance warning and are more catastrophic. Deficiencies in shear can be due to insufficient shear reinforcement, use of outdated design codes, a reduction in the steel area due to corrosion, or an increase in the service load due to change of occupancy for the structure.

In recent years, many research studies have investigated the shear behavior of reinforced concrete (RC) beams strengthened with fiber-reinforced polymer (FRP) composites, however, most of them were conducted on small-scale specimens. Thus, analytical models and design …

Risk Assessment Of Various Median Treatments Of Rural Interstates, Natalie M. Villwock, Nicolas Paul Blond, Andrzej P. Tarko

JTRP Technical Reports

This report presents results of a comprehensive study that evaluates the safety impacts of alternative median treatments on rural freeways. Extensive data were obtained from Indiana, Colorado, Illinois, Iowa, Missouri, New York, Ohio, Oregon, Washington, and Wisconsin. The studied median treatments include AASHTO-recommended treatments: depressed medians, depressed medians with high and lowtensioned cable barriers, and flush medians with concrete barriers. Other treatments used in the freeway design were also studied: medians with berms, sloped medians, and depressed medians with berms. Negative binomial models were developed to predict the frequency of crashes in three categories: single vehicle (SV), multiple vehicles same …

Investigating The Effect Of Stress, Wetting, And Compaction On Settlement Potential Of Mine Spoils, Lauren M. Little

University of Kentucky Master's Theses

Strip mining in Kentucky has left large areas of land that could potentially be used for business and housing developments. However, the mine spoils underlying these areas are prone to severe differential settlement due to a variety of factors. Mine spoil from the Gateway Business Park in Jenkins, Kentucky was used for a series of laboratory tests to develop relationships between shear wave velocity, confining stress, compaction energy, and dry unit weight to develop a method to assess settlement potential. It was found that a stress-corrected shear wave velocity of greater than 275 ft/s/psi^0.25 typically indicated dry mine spoil, …