Civil and Environmental Engineering Commons^™

Rectification Of 2-D To 3-D Finite Element Analysis In Buried Concrete Arches Under Discrete Loading, Adam D. Aagard

Theses and Dissertations

Construction of tunnels and small- to medium-span bridges is a $12 billion per year industry in the United States, with a significant portion going into buried arch structures. Notwithstanding such expenditure, modern arch design and construction, in many cases, is highly conservative. This is because the closed-form solutions used by most designers today do not correctly account for soil-structure interaction. In fact, soil-structure interaction makes a closed form solution impossible. With the advent of high power computers in recent years, some designers have turned to finite element (FE)modeling as the main vehicle of analysis. Such numerical procedures provide an accurate …

Lifetime Testing Of Wire-Grid Polarizers With Selected Over-Coatings, Steven J. Malone

Theses and Dissertations

Wire-grid polarizers (WGPs) offer superior extinction, durability, angle of incidence, and heat resistance when compared to traditional organic polarizers. WGPs are found in applications such as high lumen lighting, laser devices, high lumen digital cinema projectors, LED packaging, and other integrated optical applications and are driving the need for over-coatings. Over-coating a WGP has been found to increase lifetime and durability. This research provides lifetime data on coated and uncoated WGPs. WGPs over-coated with 100nm of SiO2, 300nm of MgF2, and with no over-coating were heated to temperatures of 450 ºC, 500 ºC, and 550 ºC and timed until they …

Early Age Assessment Of Cement Treated Materials, Tyler B. Young

Theses and Dissertations

In order to avoid the occurrence of early-age damage, cement-treated base (CTB) materials must be allowed to cure for a period of time before the pavement can be opened to traffic. The purpose of this research was to evaluate the utility of the soil stiffness gauge (SSG), heavy Clegg impact soil tester (CIST), portable falling-weight deflectometer (PFWD), dynamic cone penetrometer, and falling-weight deflectometer for assessing early-age strength gain of cement-stabilized materials. Experimentation was performed at four sites on a pavement reconstruction project along Interstate 84 near Morgan, Utah, and three sites along Highway 91 near Richmond, Utah; cement stabilization was …

Significant Trade Contractor Performance Characteristics As Evaluated By Big-D Construction, Conrad C. Johnson

Theses and Dissertations

The purpose of this research is to determine which aspects, other than price, of trade contractor performance are the most important to the general contractor, Big-D Construction. The impression a trade contractor leaves on the project manager and superintendent provides an indication of their performance. To determine what tasks trade contractors perform that most greatly impact overall perception of the general contractor's project manager and superintendent, hundreds of trade contractors were evaluated in ten separate categories and were then given an overall rating. The correlation between each category and the overall rating was found. The categories were then sorted from …

Modeling Dissolved Oxygen In Lake Powell Using Ce-Qual-W2, Nicholas Trevor Williams

Theses and Dissertations

Water quality models in the Colorado River Basin have been developed for the basin, river, and individual reservoirs. They are used to support water quality programs within the basin. The models are periodically reviewed and updated to improve the accuracy of simulations. Improving the usefulness of the Lake Powell model, one of the key reservoirs in the basin, is the subject of this study. Lake Powell is simulated using a hydrodynamic and water quality model, CE-QUAL-W2. Previously the model has been used at Lake Powell to simulate hydrodynamics, temperature, and total dissolved solids with a reasonable degree of accuracy. An …

Rapid Runway Repair (Rrr): An Optimization For Minimum Operating Strip (Mos) Selection, David J. Duncan

Theses and Dissertations

Minimum Operating Strip (MOS) selection determines the exact placement of the MOS on the damaged runway, and therefore, the amount of munitions that need to be neutralized and the amount of damage that will need to be repaired. MOS selection, in essence, is the key determinant of the time required to attain an operational takeoff and recovery surface. Since the MOS selection stage determines the events and scope of work for all of the Rapid Runway Repair (RRR) stages that follow, it could be argued that this is the most important stage in the entire RRR process. The primary purpose …

A Qualitative Study Of Selected Quality Knowledge And Practices In Guangdong Province, China, Tyler R. Thomas

Theses and Dissertations

The manufacturing industry has become very competitive in today's global market environment. Many US companies are faced with the choice of keeping their manufacturing domestic or looking to low cost off-shore countries to take advantage of the labor costs differences. To gain an understanding of the state of manufacturing in China, a major focus in the manufacturing world today, this thesis was undertaken. This thesis presents the findings of research conducted in Guangdong Province, China in June - July, 2005. This research addressed customer focus, leadership and general manufacturing and quality knowledge and practices of small, medium and large sized …

Decision Analysis With Value Focused Thinking As A Methodology To Select Building For Deconstruction, Erika E. Maiorano

Theses and Dissertations

The purpose of this research was to examine the reuse and recycling of building materials on Wright-Patterson Air Force Base. There are a variety of conflicting factors concerning the removal of a building and the model quantitatively evaluates alternatives with respect to the decision maker’s values. The research questions were addressed with both a comprehensive literature review as well as the implementation of the value focused thinking methodology. The model found that the temporary living facilities are the alternatives that achieve the highest value. The result of this research effort was a value model that aids decision makers in identifying …

Calibration Procedure For A Microscopic Traffic Simulation Model, Carole Turley

Theses and Dissertations

The inputs to a microscopic traffic simulation model generally include quantitative, but immeasurable data describing driver behavior and vehicle performance characteristics. Engineers often use default values for parameters such as car-following sensitivity and gap acceptance because it can be difficult to obtain accurate estimates for these parameters. While recent research has indicated that the accuracy of a simulation model can significantly improve if driver behavior parameters are calibrated to local data, this is not a typical practice. Manual calibration of these parameters is often too time-consuming to be cost-effective. Researchers have applied automated calibration procedures using genetic algorithms to these …

Modeling In Situ Bioremediation Of Perchlorate-Contaminated Groundwater, Roland E. Secody

Theses and Dissertations

Perchlorate-contaminated groundwater is a significant problem for the Department of Defense and the United States Air Force. An innovative technology was recently developed which uses dual-screened treatment wells to mix an electron donor into perchlorate-contaminated groundwater in order to effect in situ bioremediation of the perchlorate by indigenous perchlorate reducing bacteria without the need to extract the contaminated water from the subsurface. In this study, a model that simulates operation of the technology is calibrated and validated using 761 days of observational data obtained from a field-scale technology evaluation project. A genetic algorithm was used with the first 113 days …

Biofiltration As A Viable Alternative For Air Pollution Control At Department Of Defense Surface Coating Facilities, David M. Hudock

Theses and Dissertations

Surface coating operations at aircraft depot facilities are common throughout the Department of Defense (DoD). During paint application processes at Navy and Marine Corps Fleet Readiness Centers (FRCs), spray paints emit volatile organic compounds (VOCs) known to have harmful effects on human health and the environment. FRC East at Marine Corps Air Station Cherry Point, does not control the emissions of VOCs from any of its paint booths. The purpose of this research is to determine if FRC East and its surrounding area can benefit both economically and environmentally from a biofiltration system for air pollution control (APC) rather than …

Parameter Importance Of An Analytical Model For Transport In The Vadose Zone, Tanner Hans Bushnell

Theses and Dissertations

The American Society of Testing and Materials (ASTM) has established a three tier risk-based corrective action (RBCA) program for cleaning up petroleum release sites, which is supported by the Environmental Protection Agency. RBCA programs make the cleanup of spill sites more efficient by requiring additional site information only when a more accurate risk assessment is needed. For spill sites that do not pass the first tier general assessment, a Tier 2 evaluation involving site specific information and screening level models to assess the potential risk must be conducted. Screening level models generally require site specific input parameters. To increase efficiency …

Culvert Hydraulics: Comparison Of Current Computer Models, Elizabeth Anne Thiele

Theses and Dissertations

The hydraulic analysis of culverts is complicated when using hand calculations. Fortunately, several computer programs are available to assist in analyzing culvert hydraulics, some of which include HY-8, Fish X-ing, Broken-back Culvert Analysis Program (BCAP), Hydraflow Express, Culvert Master, Culvert, and Hydrologic Engineering Center River Analysis System (HEC-RAS). While all of these programs can simulate the behavior of flow through a culvert, slightly different methodologies are utilized among the programs to complete a full hydraulic analysis, resulting in different predictions for headwater depth, flow control, and outlet velocities. The purpose of this paper is to compare (1) the available hydraulic …

Development Of A Screening Model For Design And Costing Of An Innovative Tailored Granular Activated Carbon Technology To Treat Perchlorate-Contaminated Water, William C. Powell

Theses and Dissertations

Perchlorate contamination of drinking water is a problem that has recently gained national attention. The purpose of this research was to develop a tool to predict the cost and performance of tailored granular activated carbon (T-GAC), an innovative technology to treat perchlorate-contaminated water. The ability to predict cost and performance is essential to promote transfer and commercialization of innovative technologies. This study investigated how data obtained from small-scale laboratory tests could be applied to predict cost and performance of a full-scale T-GAC system to treat perchlorate-contaminated water. A technology model was developed using GAC design principles and using a multi-component …

Spot Friction Welding Of Ultra High-Strength Automotive Sheet Steel, Jack H. Sederstrom

Theses and Dissertations

Spot friction welding (SFW) was performed on ultra high strength steel (UHSS) steel sheet commonly used in automobile manufacturing. Alloys studied included DP780, DP780EG, DP980, and DF140T sheet steel of varying thickness from 1.2 mm to 1.4 mm. Welding was accomplished using a PCBN standard tool. Weld strengths were then compared to a proposed AWS standard. Initial hardness readings were taken in cross sectioned samples. Grain structure in a SFW is presented. Resistance spot welds were created in three steels. This study focuses on the strength of SFW joints as compared to traditional resistance spot welding (RSW) in welding like …

The Effects Of Orthophosphate As A Copper Corrosion Control Inhibitor In High Alkalinity Drinking Water Systems, Stephen Grace

Theses and Dissertations

The purpose of this research was to investigate orthophosphate as a corrosion inhibitor for copper pipe in a high-alkalinity drinking water system. Specifically, this thesis sought to answer three research questions regarding the impact of orthophosphate treatment, the nature of the mechanism by which orthophosphate controls copper corrosion, and the value of equilibrium modeling in predicting orthophosphate’s effects. The research questions were answered through a comprehensive literature review and experimental methodology integrating laboratory jar tests, water sampling and analysis from a field investigation, qualitative solids analysis, and equilibrium model application. This study analyzed field data obtained over the course of …

Characterization Of Chlorinated Ethene Degradation In A Vertical Flow Constructed Wetland, James M. Waldron

Theses and Dissertations

Chlorinated solvents, including perchloroethene (PCE) and trichlorethene (TCE), are among the most common groundwater contaminants found in the United States. Once released into the environment, chlorinated solvents are extremely persistent and often require costly and lengthy remedial actions. The use of constructed wetlands has shown promise as an effective and less costly alternative for the treatment of chlorinated solvent contaminated groundwater. This study characterized and evaluated the concentration of chlorinated ethenes within a vertical flow constructed wetland, fed with PCE contaminated groundwater, at Wright-Patterson Air Force Base (WPAFB), Ohio. Chlorinated ethene concentrations were characterized within three distinct layers of the …

A Decision Model For Selecting Energy Efficient Technologies For Low -Sloping Roof Tops Using Value-Focused Thinking, Michael J. Mccourt

Theses and Dissertations

The Air Force has a large inventory of low-sloping built up roofs (BURs) and millions of dollars are spent each year retrofitting these systems. The DOD has been directed to reduce non-renewable energy consumption by using energy-efficient technologies. These two details present a great opportunity to use the open roof space to install energy-efficient roofing technologies. The purpose of this research is to provide Air Force decision makers with a tool to assist them in deciding what roofing technologies should be installed on facilities. Value Focused-Thinking is the methodology used to construct the model, in which values were used, instead …

A Value-Focused Thinking Model For The Selection Of The Best Rigid Pavement, Partial-Depth Spall Repair Material, Benjamin G. Speer

Theses and Dissertations

Concrete spalls on airfield pavements generate foreign object debris (FOD) that is damaging to aircraft engines, and may damage landing gear by roughening of the pavement surface. Repairing spalled concrete on aging and deteriorating airfields is essential for its safe operational use. Picking the best repair material from many products on the commercial market is difficult. There is wide variation on material properties, and good performance on certain criteria is critical to constructing long lasting repairs. Since there is currently no procedure for Air Force decision-makers to select the best rigid-pavement repair material, a model was created using Value-Focused Thinking …

Using Value-Focused Thinking To Evaluate The Use Of Innovative Stormwater Management Technologies On Air Force Installations, Jeffrey T. Falcone

Theses and Dissertations

Stormwater runoff occurs naturally after every storm event; however, traditional development practices have created many impervious surfaces, such as buildings, parking lots, and streets that increase runoff volume and flow rate. Conventional stormwater management practices focus on collecting runoff into centralized channels and conveying it as quickly as possible to local bodies of water. This type of conveyance system decreases the opportunity for stormwater to naturally infiltrate back into the ground. It also prevents contaminants from being naturally filtered out of stormwater flows. As a result, centralized conveyance systems can cause flooding, erosion, and terrestrial and aquatic habitat degradation. Innovative …

Effect Of Initial Surface Treatment Timing On Chloride Concentrations In Concrete Bridge Decks, Aimee Worthen Birdsall

Theses and Dissertations

Bridge engineers and managers in coastal areas and cold regions frequently specify the application of surface treatments on concrete bridge decks as barriers against chloride ingress. In consideration of concrete cover thickness and the presence of stay-in-place metal forms (SIPMFs), the objective of this research was to determine the latest timing of initial surface treatment applications on concrete bridge decks subjected to external chloride loading before chlorides accumulate in sufficient quantities to initiate corrosion during the service life of the deck. Chloride concentration data for this research were collected from 12 concrete bridge decks located within the I-215 corridor in …

Design And Construction Of Pavements In Cold Regions: State Of The Practice, Brad Steven Smith

Theses and Dissertations

The effects of frost action introduce many challenges in the design and construction of roadways in cold regions throughout the United States. The penetration of frost into pavement structures can lead to differential frost heave during winter and thaw weakening during spring. Both of these damage mechanisms lead to premature pavement distress, structural deterioration, and poor ride quality. Because the availability of naturally occurring non-frost-susceptible pavement base materials is rapidly diminishing in many areas while project budgets remain largely inadequate, pavement engineers are utilizing alternative materials and techniques to minimize such damage. The purpose of this research was to investigate …

An Analysis Of The Accounting Methods Used By Builders Producing Twenty-Five Or Fewer Homes Per Year, David Andrus

Theses and Dissertations

Accounting plays a crucial role in the success of any business, but it is particularly vital in the construction industry, a complex field that typically requires the coordination of multiple subcontractors and multiple jobs in any given year. Although small-volume home builders make up 70 percent of the membership of the National Association of Home Builders (NAHB), a trade association of the home building industry, little is known about the accounting practices of these builders. This thesis undertook to study the accounting practices of small-volume home builders. Small-volume home builders were defined as those producing 25 homes or fewer in …

Impact Of Wastewater Reuse In Burlington County On Surface Water Quality And Adjacent Wetlands, Crystal L. Mattson

Theses and Dissertations

This study was conducted to assess potential ecological impacts from application of treated wastewater effluent. Indian Springs Golf Course is currently irrigated with reclaimed wastewater. Grab water samples were collected from three (3) ponds located on the golf course over the course of a year and were analyzed for nitrate-nitrogen, total phosphorus, organics, and bacteria. A second golf course, Medford Lakes Country Club is currently irrigated with groundwater. Grab water samples were collected from both locations and analyzed for nutrients and bacteria for comparison purposes.

Results of sample analyses indicate that detriment to the quality of surface water at the …

Utah Commercial Motor Vehicle Weigh-In-Motion Data Analysis And Calibration Methodology, Luke W. Seegmiller

Theses and Dissertations

In preparation for changes in pavement design methodologies and to begin to assess the effectiveness of the weigh-in-motion (WIM) system in Utah, the Utah Department of Transportation (UDOT) contracted with a Brigham Young University (BYU) research team to conduct an evaluation of their commercial motor vehicle (CMV) data collection system statewide. The objective of this research was to evaluate the CMV data collection program in the state of Utah and to make limited recommendations for potential improvements and changes that will aid in more detailed and accurate CMV data collection across the state. To accomplish the research objectives, several tasks …

Consolidation And Interweaving Of Composite Members By A Continuous Manufacturing Process, Sarita L. Kesler

Theses and Dissertations

Recent research and development has resulted in a working prototype of an automated process for manufacturing IsoTruss® and other innovative open lattice composite structures which yields faster, and more predictable and consistent parts, while automatically consolidating individual members. This machine is sufficiently versatile to manufacture any type of open lattice structure fabricated from filamentary composite materials. The objectives of the research in this thesis were two-fold: (1) to validate this new process for making IsoTruss structures; and (2) to measure the compression strength and stiffness of specimens produced on the machine. In order to accomplish the first purpose, various parts …

A New Spectroscopic Method For The Non-Destructive Characterization Of Weathering Damage In Plastics, Andrew Robert George

Theses and Dissertations

The weathering of plastics and composites is a problem because of the loss of both physical and mechanical properties that it causes in these materials. But this weathering effect has been difficult, and in some cases, impossible to characterize without the destruction of the plastic or composite part. Clearly a rapid, reliable, and non-destructive test for the extent of the weathering damage is critically needed. A recent problem that arose at Superyacht Solutions, a boat repair company in Australia, required a solution to just this problem. Such a test was developed for Superyacht Solutions, and is being applied across a …

Assessment Of The Tube Suction Test For Identifying Non-Frost-Susceptible Soils Stabilized With Cement, Amy Lyn Crook

Theses and Dissertations

Frost heave is a primary mechanism of pavement distress in cold regions. The distress exhibited is dependent on the frost susceptibility of the soil within the depth of frost penetration, the availability of subsurface water, and the duration of freezing surface temperatures. Cement stabilization is one technique used to mitigate the effects of frost heave. The tube suction test (TST) is one possible method for determining the frost susceptibility of soils in the laboratory. The purpose of this research was to assess the utility of the TST for identifying non-frost-susceptible (NFS) materials stabilized with cement. This research investigated two aggregate …

Automatic, Unstructured Mesh Generation For 2d Shelf Based Tidal Models, Cameron L. Mcdonald

Theses and Dissertations

Numeric models use a collection of triangular facets called elements connected over a domain in what is referred to as a mesh or unstructured grid as the computational basis for calculations. The density of elements in a mesh affects the numeric stability of a model when performing computations. Furthermore, these meshes can be difficult and time consuming to create. This thesis describes an automated process of creating meshes which utilizes local truncation analysis to generate a spatially varied size function. An advancing frontal mesh generation algorithm uses this function to optimize node placement and density. Further analysis to better understand …

Analysis Of The Sediment Transport Capabilities Of Feswms Fst2dh, Mark K. Ipson

Theses and Dissertations

Many numeric models simulate the transport of sediment within rivers and streams. Engineers use such models to monitor the overall condition of a river or stream and to analyze the impact that the aggradation and degradation of sediment has on the stability of bridge piers and other features within a stretch of a river or stream. A model developed by the Federal Highway Administration, FST2DH, was recently modified to include the simulation of sediment movement within a channel. The tools for modeling sediment movement with FST2DH remain unproven. This thesis examines the sediment capabilities of FST2DH. It evaluates the sediment …