Civil and Environmental Engineering Commons^™

Reliability-Based Underseepage Analysis In Levees Using Monte Carlo Simulation, Lourdes Polanco

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A new method for assessing the potential for unsatisfactory levee performance due to underseepage is presented. Specifically, the method assesses the potential for the initiation of piping (the internal backward erosion of the foundation or embankment caused by seepage). Current assessment methods consist of deterministic seepage analyses and simplified reliability methods. Deterministic methods produce either a maximum hydraulic exit gradient or a Factor of Safety against piping but they do not account for high levels of uncertainty in soil properties and subsurface geometry that are inherent to many levee analyses. The most common simplified reliability approaches that are currently being …

Internal Design Of Mechanically Stabilized Earth (Mse) Retaining Walls Using Crimped Bars, Bernardo A. Castellanos

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Current design codes of Mechanically Stabilized Earth (MSE) Walls allow the use lower lateral earth pressure coefficient (K value) for designing geosynthetics walls than those used to design steel walls. The reason of this is because geosynthetics walls are less rigid permitting the wall to deform enough to work under active pressures instead of at rest pressures as in steel walls.

A new concept of crimped steel bars was recently introduced. This new type of bar was tested for tension and pullout behavior. Results on tests made on crimped bars show that putting those crimps in the steel bar will …

Increased Functionality Of Floodplain Mapping Automation: Utah Inundation Mapping System (Utims), Brian K. Stevens

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Floodplain mapping has become an increasingly important part of floodplain management. Floodplain mapping employs mapping software and hydraulic calculation packages to efficiently map floodplains. Modelers often utilize automation software to develop the complex geometries required to reduce the time to develop hydraulic models.

The Utah Inundation Mapping System (UTIMS) was designed to reduce the time required to develop complex geometries for use in floodplain mapping studies. UTIMS reduces the time required to develop geometries used in floodplain management studies. The automated geometries developed include: flood specific river centerlines, bank lines, flow path lines, cross sections, and areal averaged n-value polygons. …

Ultimate Shear Capacity And Residual Prestress Force Of Full-Scale, Forty-One-Year-Old Prestressed-Concrete Girders, Parry Osborn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The ultimate shear capacity of prestressed concrete beams is difficult to predict accurately, especially after being in service for an extended period of time. The Utah Department of Transportation asked researchers at Utah State University to experimentally determine the existing shear capacity of 41-year-old prestressed, decommissioned concrete bridge girders and then provide recommendations on how to increase that ultimate shear capacity. This thesis presents the research findings that relate to the existing shear capacity of the prestressed concrete girders.

Eight AASHTO Type II bridge girders were tested up to failure by applying external loads near the supports to determine their …

Multivariate Bayesian Machine Learning Regression For Operation And Management Of Multiple Reservoir, Irrigation Canal, And River Systems, Andres M. Ticlavilca

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The principal objective of this dissertation is to develop Bayesian machine learning models for multiple reservoir, irrigation canal, and river system operation and management. These types of models are derived from the emerging area of machine learning theory; they are characterized by their ability to capture the underlying physics of the system simply by examination of the measured system inputs and outputs. They can be used to provide probabilistic predictions of system behavior using only historical data. The models were developed in the form of a multivariate relevance vector machine (MVRVM) that is based on a sparse Bayesian learning machine …

Distributed Hydrological Modeling Using Soil Depth Estimated Based On Landscape Variables From Enhanced Terrain Analysis, Teklu K. Tesfa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The spatial patterns of land surface and subsurface characteristics determine the spatial heterogeneity of hydrological processes. Soil depth is one of these characteristics and an important input parameter required by distributed hydrological models that explicitly represent spatial heterogeneity. Soil is related to topography and land cover due to the role played by topography and vegetation in affecting soil-forming processes. The research described in this dissertation addressed the development of statistical models that predict the soil depth pattern over the landscape; derivation of new topographic variables evaluated using both serial and parallel algorithms; and evaluation of the impacts of detailed soil …

Full-Scale Testing Of 40 Year Old Prestressed Aashto Girders That Have Been Retrofitted In Shear By Externally Applied Carbon Fiber Reinforced Polymer Wraps, David A. Petty

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Utah Department of Transportation (UDOT) is interested in the application of rehabilitation techniques to strengthen their AASTHO prestressed bridge girders for shear. Utah's bridges are exposed to deterioration from rain, snow, and the introduction of salt for ice removable. This requires innovative rehabilitation techniques to address the deteriorations of their highway bridges, especially the ends of bridge girders where water and salt are more common due to construction joints. Carbon Fiber Reinforced Polymers (CFRP) are becoming more prevalent as a tool in highway bridge rehabilitation.

This research investigates the application of various CFRP systems that can be used as …

Changes In Hybrid Poplar Endophytic Microbial Diversity In Response To Trichloroethylene Exposure, Jared S. Ervin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Remediation of trichloroethylene (TCE) is a major priority for many contaminated sites all over the industrialized world including Hill Air Force Base, UT (HAFB). Phytoremediation as part of a cleanup strategy is an appealing option, and trees at HAFB have been studied to this end. Trees have also been used to delineate groundwater plumes because the passive uptake of organic contaminants by trees generally results in a direct relationship between tree and groundwater TCE concentrations if the trees are using the contaminated groundwater. However, the concentrations of plant-produced TCE metabolites can vary greatly. It was hypothesized that the endophytic microbial …

Performance Of Nevada’S Aggregates In Alkali-Aggregate Reactivity Of Portland Cement Concrete, Mohammad Shahidul Islam

UNLV Theses, Dissertations, Professional Papers, and Capstones

Alkali-aggregate reaction (AAR) is a form of distress that occurs in concrete and results in serviceability problems, cracks, spalling, and other deterioration mechanisms. There are two categories of AAR, namely, alkali-silica reaction (ASR) and alkali-carbonate reaction (ACR). Alkali-silica reaction is one of the most recognized deleterious phenomena in concrete, and has been a major concern since its discovery in the 1940s. The reaction which occurs between reactive silica or silicates present in some aggregates and alkalis of Portland cement produces an alkali-silica gel that expands in the presence of moisture resulting in concrete cracks. ACR is also a chemical reaction …

An Exploratory Study On Energy Consumption Of Energy Star And Non-Energy Star Homes, Prajakta Kulkarni

UNLV Theses, Dissertations, Professional Papers, and Capstones

The reduction of energy consumption is one of the economic necessities in the United States due to depleting energy sources in the world. The construction industry is stepping forward to reduce the energy consumption of buildings by efficient designs or by constructing buildings with energy efficient materials and features. In 1992, the U.S. Environmental Protection Agency (EPA) and Department of Energy (DOE) introduced the Energy Star Program to promote energy efficient products with the same or improved services. According to the EPA, Energy Star homes, which use these products, will consume 20 to 30 percent less energy than non-Energy Star …

Assessment Of Impacts To Hydroclimatology And River Operations Due To Climate Change Over The Colorado River Basin, William Paul Miller

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation investigated the impacts of climate change to the hydroclimatology and river and reservoir management operations within the Colorado River Basin. Preliminary research indicated observed warming trends throughout the Colorado River Basin and corresponding seasonal trends to the magnitude and timing of runoff in the Colorado River Basin. Subsequent research investigated the changing character of precipitation and corresponding impacts to streamflow over the Colorado River Basin. Analysis of snowpack telemetry (SNOTEL) stations over the American West and Colorado River Basin indicated decreasing trends in annual snowpack, often at least at the 95% confidence interval. A shorter snowpack season was …

Ion-Exchange (Ix): Arsenic And Chromium Removal From Brines And Removal Of Inorganic Contaminants By Specialty Resins, Behrang Pakzadeh

UNLV Theses, Dissertations, Professional Papers, and Capstones

Although ion exchange is highly efficient in removing inorganic contaminants, similar to other water treatment technologies, ion exchange has some drawbacks that need to be studied further. Three issues related to drawbacks of ion-exchange resins in water treatment were addressed in this research. The first issue was the influence of anionic inorganic co-contaminants including nitrate, Cr(VI), Se(VI), and As(V) on the performances of nitrate and perchlorate specialty (selective) resins in water treatment. It was found that nitrate can be removed from waters using perchlorate specialty resins, but the resin is poorly regenerated. Perchlorate was not easily removed from either nitrate …

Evaluation Of Safety Impact Of Access Management In Urban Areas, Xuecai Xu

UNLV Theses, Dissertations, Professional Papers, and Capstones

The access provided by streets and highways to adjacent lands are managed by controlling the spacings between the access points including signals, driveways, and media openings on mid-block segments, and setting the limit on the corner clearances around intersections. There have been studies on evaluating the impact of access management techniques on safety and mobility in urban areas. Samples of mid-block segments and intersections can be collected from selected arterials. Because the mid-block segments or intersections in the same arterials share the same missing information, safety and mobility on them show unique features that should be taken into account when …

Energy And Nutrient Recovery From Anaerobic Treatment Of Organic Wastes, Christian-Dominik Henrich

All Dissertations

The objective of the research was to develop a complete systems design and predictive model framework of a series of linked processes capable of providing treatment of landfill leachate while simultaneously recovering nutrients and bioenergy from the waste inputs. This proposed process includes an 'Ammonia Recovery Process' (ARP) consisting of: 1) ammonia de-sorption requiring leachate pH adjustment with lime or sodium hydroxide addition followed by, 2) ammonia re-absorption into a 6-molar sulfuric acid spray-tower followed by, 3) biological activated sludge treatment of soluble organic residuals (BOD) followed by, 4) high-rate algal post-treatment and finally, 5) an optional anaerobic digestion process …

Oscillation Phenomenon Of The New York Canal At The I-84 Overpass In Boise, Idaho, Erik W. Robison

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

As part of the Idaho Transportation department's GARVEE program, the 1-84 bridge structure at the New York Canal in Boise, Idaho, was widened in 2009. During the 2009 irrigation season, oscillation patterns were noticed at the bridge structure which resulted in erosion damage to the banks of the canal. After ITD consulted with Horrocks Engineers, a contract was established with the Utah Water Research Laboratory at Utah State University to construct a Froude scale model of the structure. The purpose of the model was to determine the cause of the oscillations, and develop an effective method to eliminate them. The …

Development Of A Structural Index As An Integral Part Of The Overall Pavement Quality In The Indot Pms, William Frederick Flora, Ghim Ping (Raymond) Ong, Kumares C. Sinha

JTRP Technical Reports

No abstract provided.

Affordable Lightweight High Performance Concrete (Alwhpc): Expanding The Envelope Of Concrete Mix Design, Kevin J. Simons

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

One way to reduce excess material would be to lighten the load on a structure with the use of affordable lightweight high performance concrete (ALWHPC). Most or all lightweight high performance concrete mixes used today include lightweight aggregates as the coarse aggregate and sand for the fine aggregate. ALWHPC mix designs contain all lightweight aggregates and cementitious materials that are readily available throughout the United States. Instead of 115 – 120 pcf, ALWHPC mix designs range from 88 – 100 pcf and strengths from 2,700 – 8,700 psi compressive strength. This research will explore the use of local lightweight aggregates …

Bs News May/June

Building Services Engineering

No abstract provided.

Optimization And Economic Evaluation Of Industrial Gas Production And Combined Heat And Power Generation From Gasification Of Corn Stover And Distillers Grains, Ajay Kumar, Yaşar Demirel, David D. Jones, Milford Hanna

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Thermochemical gasification is one of the most promising technologies for converting biomass into power, fuels and chemicals. The objectives of this study were to maximize the net energy efficiency for biomass gasification, and to estimate the cost of producing industrial gas and combined heat and power (CHP) at a feedrate of 2,000 kg/h. Aspen Plusbased model for gasification was combined with a CHP generation model, and optimized using corn stover and dried distillers grains with solubles (DDGS) as the biomass feedstocks. The cold gas efficiencies for gas production were 57% and 52%, respectively, for corn stover and DDGS. The selling …

Freight Performance Measures: Approach Analysis, B. Starr Mcmullen, Christopher M. Monsere

Civil and Environmental Engineering Faculty Publications and Presentations

This report reviews the existing state of the art and also the state of the practice of freight performance measurement. Most performance measures at the state level have aimed at evaluating highway or transit infrastructure performance with an emphasis on passenger transportation. Freight performance measurement ultimately requires evaluation of performance of the entire freight transportation system, which includes highways, waterways, rail, air, and modal connections. This requires considerable expansion of thinking beyond the traditional focus of state Departments of Transportation (DOTs) on highway performance.

This project builds upon past and current work in the area of freight performance measurement and …

Data Analysis Of Utah's I-80 And I-215 Bridges - For The Use In The Development Of Accelerated Bridge Construction Standards, Erik S. Rosvall

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study discusses five bridges on Utah's I-80 that were replaced in the summer of 2008 using Accelerated Bridge Construction methods. Each superstructure was built offsite and moved into place with the use of Self-Propelled Modular Transporters. The bridges were instrumented and monitored during the moving process to investigate the effects of moving an entire superstructure into place. Collected data was analyzed to find the level of stress each superstructure experienced during lifting, moving, and placement of each bridge.

The change in supporting conditions from when the superstructure was built to being transferred onto Self-Propelled Modular Transporters caused significant stress …

Remotely Sensed Data Assimilation Technique To Develop Machine Learning Models For Use In Water Management, Bushra Zaman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Increasing population and water conflicts are making water management one of the most important issues of the present world. It has become absolutely necessary to find ways to manage water more efficiently. Technological advancement has introduced various techniques for data acquisition and analysis, and these tools can be used to address some of the critical issues that challenge water resource management.

This research used learning machine techniques and information acquired through remote sensing, to solve problems related to soil moisture estimation and crop identification on large spatial scales. In this dissertation, solutions were proposed in three problem areas that can …

Effects Of Submergence In Montana Flumes, Ryan P. Willeitner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As part of a continued research project for the Utah Water Research Laboratory and the State of Utah, a study of flow measurement devices is being conducted throughout the state. Initially the project included only measurement devices associated with high-risk dams, but has since been broadened to any measurement structure of interest for water users in the state. The physical dimensions, relative elevations, and flow accuracy were documented for each included device.

After visiting sixteen sites, it was found that fourteen of the measuring devices had incorrect geometries. Of these fourteen, thirteen of them were originally Parshall flumes. A large …

Fundamentals Of Operation Of The Induced Bed Reactor (Ibr) Anaerobic Digester, Jacob Shaun Dustin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Induced Bed Reactor (IBR) was developed at Utah State University to apply high-rate anaerobic digestion techniques to high solids content substrates. This technology has been successfully implemented at full-scale multiple installations in the United States and Canada as a waste treatment and energy production technology, but the physical processes necessary to further optimize the system were not well understood.

Bench scale IBRs were operated as anaerobic digesters at 35°, 45°, and 55° C under three organic loading rates and three corresponding hydraulic retention times. Reactor performance was monitored at steady state for residence time distribution and substrate reduction.

The …

Long-Term Performance Of Pavement Markings On Primary And Secondary Roads, Joshua Johnson

All Theses

This research analyzes waterbased and thermoplastic pavement markings on primary and secondary roads in South Carolina. The primary objective of this research was to develop retroreflectivity degradation models for these two pavement marking materials, as well as determine the expected useful life of the markings. Predicting retroreflectivity and marking life is important so that state DOTs may efficiently replace markings in order to reduce safety hazards as well as maintenance costs.
Data collection for this research lasted 21 months, where retroreflectivity of pavement markings was measured on over 100 primary and secondary roads in South Carolina. Variables such as marking …

Modeling Phosphate Adsorption For South Carolina Soils, Jesse Cannon

All Theses

Eroded sediment and the pollutants it transports are problems in water bodies in South Carolina (SC) and the United States as a whole. Current regulations and engineering practice attempt to remedy this problem by trapping sediment according to settling velocity, and thus, particle size. However, relatively little is known about most eroded soils. In most cases, little experimental data are available to describe a soil's ability to adsorb a pollutant of interest. More-effective design tools are necessary if design engineers and regulators are to be successful in reducing the amount of sediment and sediment-bound pollutants in water bodies. This study …

Comparision Of Open Graded Friction Course Mix Design Methods Currently Used In The United States, Laura Kline

All Theses

This research compares the open graded friction course (OGFC) mix design methods which are currently being used in the United States. OGFCs are a type of porous pavement that have been used in the United States since 1944, but has provided inconsistent and highly variable performance results. The design procedures for several agencies were obtained, and then compared for similarities. All of the design methods were then conducted to determine the optimum binder content. The optimum binder content (OBC) of a single aggregate gradation for each method was tested for properties and performance characteristics.
The design methods which are currently …

Performance Evaluation Of Sbs Modified Asphalt Mixtures Using Warm Mix Technologies, Hakseo Kim

All Theses

The need for more sustainable methods and techniques in industry has been increasing and it is important to respond to the needs of society and address issues surrounding its environment and health. In order to better introduce such new and more sustainable methods, it is necessary to combine existing and proven methods with new technology. The main idea of this research was to use the established industry standard of using Styrene Butadiene Styrene (SBS) modified binder and combine it with the relatively new Warm Mix Asphalt (WMA) technology in order to create a more sustainable and eco-friendly asphalt paving process. …

Biodegradation And Bioremediation Of Hexachlorocyclohexane Isomers, Chlorinated Ethenes, Chlorinated Benzenes And Benzene, Vijaikrishnah Elango

All Dissertations

ABSTRACT
Groundwater at an industrial site is contaminated with γ -hexachlorocyclohexane (HCH) and α-HCH (i.e., lindane) (0.3-0.5 ppm). Other contaminants in the 1-15 ppm range include 1,2,4-trichlorobenezene (TCB), 1,2-dichlorobenzene (DCB), 1,3-DCB, 1,4-DCB, chlorobenzene (CB), benzene, trichloroethene (TCE) and cis-1,2-dichloroethene (cDCE). The aquifer consists of a shallow layer of soil over fractured dolomite, where most of the contaminant mass resides. The objective of this study was to compare 1) anaerobic reductive dechlorination of the polychlorinated contaminants, followed by aerobic biodegradation of the daughter products (mainly DCBs, CB, and benzene); and 2) aerobic biodegradation of α- and γ-HCH, TCB, DCBs, CB and …

Occurrence And Formation Of Disinfection By-Products In Indoor Swimming Pools Water, Amer Kanan

All Dissertations

Chlorination is used to prevent the spread of waterborne infectious diseases from swimming pools. This required disinfection practice also results in the formation of undesirable disinfection by-products (DBPs) from the reactions of chlorine with the organic matter (released by swimmers or present in the filling water of the pool) and bromide. Some of these DBPs have important adverse public health effects; as a result their concentrations in drinking waters are regulated. Unfortunately, DBPs formation and control in swimming pools have not been studied and investigated to the same extent as their formation and control in drinking water.
The main objective …