Digital Commons Network^™

Exploring Anaerobic Reductive Dechlorination At Low Ph Environments, Yi Yang

Masters Theses

Chlorinated aliphatic hydrocarbons (CAHs), such as tetrachloroethene (PCE) and trichloroethene (TCE), are ubiquitously pollutants in aquifer sediments and groundwater due to their heavy usage in industry and inappropriate disposal in the last century. Among about 1300 NPL (National Priorities List) sites, PCE and TCE are the two most frequently detected hazardous contaminants.

Engineered bioremediation, including biostimulation and bioaugmentation, is a promising technology to clean those PCE and/or TCE contaminated sites. However, in many contaminated groundwater systems and hazardous waste sites, pH can be lower than 5 to 6. And release of HCl (strong acid) from anaerobic reductive dechlorination may lower …

The Implementation Of A Versatile Pseudodynamic Hybrid Simulation For Seismic Evaluation Of Structural Systems, Chelsea Griffith

Masters Theses

Pseudodynamic hybrid simulation technique was developed to evaluate structural seismic performance by physically testing the critical portion with the remaining structure simulated using a numerical model in the computer. An incremental approach was adopted in developing the control scheme to suit multiple testing facilities and test specimens. First the small scale, predictable specimen was utilized to investigate techniques of improving stability, slowing down the loading rate and triggering the accurate force measurement in a series of at benchmark scale experiments in the Laboratory of Earthquake and Structural Simulation at Western Michigan University (WMU). A step/hold command scheme was developed and …

Estimates Of Glacier Mass Loss And Contribution To Streamflow: Wind River Range (Wyoming, Usa), Jeffrey Allen Marks

Masters Theses

The Wind River Range is a continuous mountain range approximately 160 km in length in west-central Wyoming. The Wind River Range is host to roughly 680 snow and ice bodies with 63 of these considered glaciers including seven of the ten largest glaciers in the American Rocky Mountains. The presence of glaciers results in meltwater contributions to streamflow during the late summer (July, August, and September – JAS) when snowmelt is decreasing, temperatures are high, precipitation is low, and irrigation demand continues. Most studies indicate that the glaciers in the Wind River Range have been retreating since the 1850’s, the …

Characterizing The Concentration, Duration, And Frequency Of Turbid Events In Tennessee Streams: Potential For Macroinvertebrate Impairment, Robert Ryan Woockman

Masters Theses

The impairment of lotic systems due to siltation is one of the most common factors leading to a stream being placed on the 303d list. Once a stream reach is placed on the 303d list, a state’s environmental regulatory agency must then develop sediment total maximum daily loads (TMDLs). However, a deficiency exists in available methods for assessing biotic response to siltation, creating the inability to set TMDLs functionally related to cause of impairment. Water quality sondes can collect voluminous amounts of turbidity data and stage data at intervals that can be used to characterize concentration, duration, and frequency (CDF) …

Application Of Highway Capacity Manual 2010 Level-Of-Service Methodologies For Planning Deficiency Analysis, James Oliver Ensley

Masters Theses

Influence on investment in the infrastructure is critical for decision-making by State planning departments. Judgments which are made for funding purposes and are based on limited data analysis by states can results in economic disasters for the state and nation. The Tennessee Department of Transportation (TDOT) uses the Evaluation of Roadway Efficiency (EVE) database to prioritize the importance of roadway projects in the state. In addition, EVE is also used as a method to provide deficiency analysis results for roadways in the state. This study will add support to the methodology of the current decision-making process in regards to Tennessee …

Utilization Of Rainwater As A Supplementary Water Source For Cooling Tower Makeup: A Sustainability Strategy For Potable Water Use Reduction, Elizabeth Stassun Costello

Masters Theses

The use of rainwater as a supplementary water source for cooling water makeup was explored in an effort to reduce the potable water demand of theUniversityofTennessee’sKnoxvillecampus. A water quality analysis involving the measurement of parameters relevant to cooling tower operation was conducted on tap water currently used for makeup supply and rainwater collected from the roof of a campus building. In anticipation of limited rainwater supplies due to issues of catchment surface area, collection efficiency, storage capacity, and climatic conditions, blends of rainwater and tap water were also analyzed. The dissolved solids concentration of the rainwater was significantly lower than …

Impacts Of Beetle Kill On Modeled Streamflow Response In The North Platte River Basin, Jordan Andrew Rudolph

Masters Theses

A beetle epidemic has been sweeping its way across the western United States and into portions of southern Canada that has caused millions of acres of forests to ultimately die. This beetle outbreak, that many have come to know simply as “beetle kill”, has caused many scientists to feel that such dramatic changes in land cover could potentially alter the hydrology throughout much of the West. One of the most important hydrological processes that beetle kill has the potential to impact is streamflow. This paper attempts to evaluate the hydrological impacts on streamflow from land cover change due to beetle …

Statistical And Numerical Integrated Approach For Detecting Onset Of Prefabricated Bridge Component Connection Deterioration, Cem Mansiz

Masters Theses

Bridges are the substantial part of the transportation infrastructure. Most recent report shows that of the 605,086 bridges in the United States, 67,526 (11%) are deemed structurally deficient, and 76,363 (13%) are declared functionally obsolete (FHWA, 2011). Deck is the shelter of a bridge that is subjected to severe loads due to exposure and traffic. Importance of detecting deck deterioration is further highlighted with the introduction of accelerated bridge construction (ABC) where prefabricated components are brought to the site, assembled, and connected using field cast joints. However, durability performance of field cast connections is not encouraging. Hence, continuous monitoring of …

Efficacy Of A Ternary Blend In Improving Bridge Deck Concrete Durability In Tennessee, Robert Clark Nidiffer

Masters Theses

A study related to the durability of bridge deck concrete in the state of Tennessee has been ongoing at the University of Tennessee (UT) for the past decade. The most recent phase of this research was begun in the fall of 2009 with a focus on developing assessment criteria and methodology to assess the durability of bridge deck concrete in the state of Tennessee. The methodology that was used to assess the durability of Tennessee bridge deck concrete was to determine the concrete’s resistance to chloride ion penetration by way of two test methods, the Surface Resistivity (SR) test and …

Two Studies On Controlling The Outflow From Sediment Basins: 1) Developing Discharge Coefficients For Circular Orifices In Round Riser Pipes, And 2) Optimizing The Solid State Skimmer, Alex James Mclemore

Masters Theses

Sediment pollution is a major contributor to stream and river impairment. Often, the source of sediment pollution is from a construction site’s runoff stormwater. A sediment retention basin, especially one with skimming outlet, can help minimize the sediment pollution from constructions sites. A sediment retention basin and outlet are specifically designed for each site to retain as much sediment as possible while satisfying other requirements such as peak flow rates and retention times. Because the modern designs needs have increased requirements, there is an increased need to be as accurate as possible when modeling the hydraulics and the sediment trapping …

Regression-Based Prioritization And Data Modeling For Customized Civil Engineering Data Collection, Omar Kanaan

Masters Theses

Civil engineers frequently face the challenges of acquiring sufficient data to satisfy the informational needs of various decision making scenarios having time, budget, and resource constraints. This thesis focuses on exploring how statistical analysis of historical data sets can be used to improve the efficiency and effectiveness of future data collection activities in transportation engineering and construction project control. Pearson's correlation, multiple regression, Akaike information criterion, and Bayesian information criterion are applied to two cases of data collection and analysis to understand the relative importance of various parameters within each case. Case I analyzes National Bridge Inventory (NBI) data to …

Structural Health Monitoring Of A Bridge Structure Using Wireless Sensor Network, Cheekian Teng

Masters Theses

Bridge Structural Health Monitoring (SHM) has rapidly become one of the main interests in civil engineering field. Inexpensive and efficient SHM method utilizing Wireless Sensor Network (WSN) is helping to facilitate the selection of the bridges that require maintenance. The changes to structural properties (i.e. stiffness) caused by damage (i.e. corrosion) will change the structural responses (i.e. acceleration responses) to ambient motions. Modal analysis algorithms applied to the vibration responses acquired through WSN provide the modal properties (i.e. natural frequency, modal shape and damping ratio) that will change with the changes in stiffness indicating possible existence of damage. Three output-only …

Soil Nitrification And Mineralization Rates Along An Elevation Gradient In The Great Smoky Mountains National Park, Christopher James Rolison

Masters Theses

The Great Smoky Mountains National Park (GRSM) is an area sensitive to acid deposition. Although reports indicate there have been reductions of acid deposition in the eastern United States, water quality in streams has not recovered to perceived natural levels. Coupled soil biogeochemical processes of nitrification and nitrogen mineralization can acidify soil water and play a key role in the fate of nitrogen-based acid deposition and observed stream acidification. Characterizing nitrogen decomposition rates at different elevations improves our understanding of the potential effects of acid deposition and soil interactions with acid ions. Soil chemical properties and potential reaction rates for …

Anticipated Changes In Precipitation Events Over The 21st Century Using Community Climate System Model, Version 4, Scott Tavish Deneale

Masters Theses

Future global daily precipitation data from Community Climate System Model, version 4 (CCSM4) were analyzed to evaluate changes in a variety of precipitation parameters over the 21st century. Multiple ensemble members of 21st century Representative Community Pathways (RCP) radiative scenarios were included in the model to provide an array of potential future climate change results. Multiple ensembles of historic daily precipitation data from CCSM4 were compared with Global Precipitation Climatology Project (GPCP) V1DD daily precipitation data and Climate Prediction Center (CPC) Merged Analysis of Precipitation (CMAP) monthly precipitation data. Annual average and 95th percentile precipitation values were averaged from 1997-2005 …

A Benefit Cost Model For Traffic Incident Management, Sam Dallas Moss

Masters Theses

Every day, non-recurring incidents cause delay on major roadways and cost the public valuable time and, hence, money. Some public agencies have systems that help them to identify and mitigate the problems associated with incidents such as delay. These systems are referred to as Traffic Incident Management systems. Many different agencies have searched for a way to quantify the benefits that these programs provide. This thesis details how a model was developed to help these agencies easily quantify the benefits that can be derived from saving delay through efficient incident management. This model uses real traffic data collected by roadway …

Analysis Of Georeferenced Sonar-Based Thalweg And Cross-Sectional River Depth Profile Measurements, Kenneth Wray Swinson

Masters Theses

Depth is a physical river characteristic that is important for habitat classification, river health analysis, and hydrologic/hydraulic modeling. Recent studies have shown that sonar can be an accurate way of measuring river depth, when compared to traditional techniques, but more study is necessary. The main objective of this research was to evaluate the utility of the CruzPro ATU120S and the Lowrance LMS-350A sonar depth units as tools for collecting river depth measurements along longitudinal (thalweg) and cross-sectional profiles. This included analyzing and evaluating the georeferenced commercially available sonar units for accuracy, precision, and response time under controlled lab and river …

A Comparison Of 7q10 Low Flow Between Rural And Urban Watersheds In Eastern United States, Saeed Zabet

Masters Theses

Abstract: Increased runoff peaks and volumes from urbanizing watersheds have been well documented where watershed hydrology becomes modified after 10 to 25% of land area is developed. Lowering of baseflow has also been reported to be modified from urbanization; however hydrology thresholds related to percentage of land area developed are not well quantified. In this study, 100 watersheds in eastern USA were investigated to examine the potential effects of urbanization on low flows. The low flow metric chosen for this analysis is the 7Q10. Historical flow records were obtained from the USGS stream gauges, in which a minimum of 10 …

Effect Of Side Edge Distance And Concrete Materials On Corrosion In Precast Prestressed Concrete Panels, Dayi Zhang

Masters Theses

"This study involved the spalling problem found in some partial-depth precast prestressed bridge decks in the state of Missouri. Recently, panels of several bridges have exhibited corrosion of the prestressing steel tendons causing concrete spalling at the edges of panels. Some of the exposed tendons are corroded to the point of rupture. The effect of factors, namely concrete side edge distance and concrete material type, on steel corrosion in chloride-contaminated reinforced concrete was investigated in this study. Wet-dry cycle tests and accelerated corrosion tests were carried out on sixty-three specimens designed with three different side edge distances and three different …

Energy Efficiency In Wastewater Treatment: Standards For Missouri Facilities, Samantha Lauren Markus

Masters Theses

"Traditionally, energy has been used to treat wastewater. As energy costs rise, so does the financial burden on communities with municipal wastewater treatment plants (WWTP). Determining energy efficiency of small to mid-sized plants is difficult because these plants are the least likely to have the resources to conduct an energy audit and the most likely to be overlooked in national models due to their small contribution to the national energy burden. Data was gathered via personal contact the WWTPs in Missouri and from this data metrics fro comparison were developed. The data was also compared to the predicted energy use …

Hardened Mechanical Properties And Durability Performance Of Specialized Concretes, Kyle Richard Holman

Masters Theses

"Concrete is one of the most produced and utilized materials in the world. Due to the labor intensive and time consuming nature of concrete construction, new and innovative concrete mixes are being explored. Self-consolidating concrete (SCC) is one such method of improving the overall cost and time efficiency of concrete production. SCC is a highly flowable form of concrete. This characteristic drastically reduces the amount of labor and time needed to place the concrete. The highly flowable nature also allows for much easier placement in applications of highly congested reinforcement.

Another rising concern in today's construction industry is environmental responsibility. …

Self-Consolidating Concrete For Infrastructure Elements Shear Characteristics, Eric B. Sells

Masters Theses

"Because of its unique ability to maintain high flow-ability and remain homogeneous, self-consolidating concrete (SCC) has the potential to significantly reduce the costs associated with civil infrastructure; however, the use of higher paste and lower coarse aggregate volumes than non-SCC concretes raises concerns about shear strength of SCC mixes. This research focused on the components that contribute to the concrete's ability to provide shear by aggregate interlock. Variables investigated by push-off tests included concrete compressive strength, coarse aggregate type , and volumetric content level of the coarse aggregate portion . Post-failure digital imaging software was used to confirm fresh concrete …

Driver Mandatory Lane Change Behavior: Use Of Governing Gap In Critical Gap Estimation, Srinadh Kandada

Masters Theses

"This study analyzed the driver gap acceptance and rejection behavior during mandatory lane changes on a multilane freeway in congested and uncongested traffic conditions. During a lane change, drivers were more receptive to either the leading or the trailing gaps with vehicles in the target lane which governed the drivers' lane change and is termed as the governing gap. Drivers maneuvered till the governing gap was greater than the critical gap, accepted the gap and made a lane change. In this process, drivers reduced the non-governing gap to increase the length of the governing gap. The drivers as a result …

Trace Element Accumulation In Rice :Effects Of Soil Arsenic, Irrigation Management, Phosphate Application And Iron Oxide Amendment, Eric Michael Farrow

Masters Theses

A concern is growing over the accumulation of trace contaminants in rice, a plant which has been estimated to supply 50% of the caloric intake to the world's population. Contamination with arsenic (As) and other trace elements have been shown in many areas including the U.S. and rice intake poses a potential risk to human health. This research investigated the accumulation of selected trace elements including arsenic (As), selenium (Se), molybdenum (Mo) and cadmium (Cd) in as many as six rice cultivars and two control soils common to the south central U.S. A field study was completed to evaluate the …

In Planta Solid Phase Sampling Devices Used In Delineating Groundwater Contaminant Plumes, Mikhil Kishore Shetty

Masters Theses

"The widespread and indiscriminate use of chlorinated volatile organic compounds as cleaning agents at dry - cleaning facilities, as metal degreasers and solvents in extraction and removal operations has been well documented in the past resulting in releases, while contaminating soil and groundwater. Current techniques to assess chlorinated solvents such as tetrachloroethylene (PCE) and trichloroethylene (TCE) in the subsurface have been time and cost intensive and more importantly invasive to the surrounding environment. New methods use trees as sources of information to access contaminant plume size and plume delineation. The major goal of these research studies has been to save …

Use Of High Volume Fly Ash-Wood Fiber And Polyurea Layers For Blast Mitigation, Anthony Francis Wulfers

Masters Theses

"This project is a continuation of research done by Natalia Carey and John Myers. The first part of Natalia's research was to develop and characterize an e-glass discrete fiber-reinforced polyurea (DFRP) system for infrastructure applications. She then recommended two polyurea systems (A and B) be further examined. These polyurea systems were then applied to plain reinforced concrete and steel fiber reinforced concrete panels (SFRC). Carey found that the SFRC panels sustained less overall damage. For this project SFRC was used as the base layer in combination with the DFRP systems. In addition to the DFRP and SFRC a high-volume fly …

Analysis Of Passive Louver Shading Systems And Impact On Interior Environment, Cory Joseph Brennan

Masters Theses

An installed passive louver shading systems can affect the heating, cooling, and lighting loads of any building, by altering the amount of solar energy, in the form of light and heat, from entering. The benefits of a louver system are derived from the application of solar geometry incident on the site and the climate within the area. By optimizing a passive louver system's design parameters, a building can reduce the total annual energy consumption due to artificial heating, cooling loads and artificial lighting. This research has implemented simulation modeling software, Energy Plus, to predict the effect of passive louver shades …

Bond Behavior Of High-Volume Fly Ash And Self-Consolidating Concrete, Trevor Jay Looney

Masters Theses

"The main objective of this study was to determine the effect on bond performance of high-volume fly ash (HVFA) concrete and self-consolidating concrete (SCC). The HVFA concrete test program consisted of comparing the bond performance of two concrete mix designs with 70% cement replacement with Class C fly ash relative to a Missouri Department of Transportation (MoDOT) standard mix design. The SCC test program consisted of comparing the bond performance of normal and high strength SCC with their respective MoDOT standard mix designs.

Two test methods were used for bond strength comparisons. The first was a direct pull-out test based …

Investigation Of The Effects Of Shrinkage, Creep, And Abrasion On Self-Consolidating Concrete And High Volume Fly Ash Concrete For Use In Transportation Related Infrastructure, Brian Timothy Tucker

Masters Theses

"Concrete specimens were fabricated for shrinkage, creep, and abrasion resistance testing. Variations of self-consolidating concrete (SCC), high volume fly ash concrete (HVFA), and conventional concrete were studied. The results were compared to previous similar testing programs and used to determine the adequacy of the materials for use in practice. These two concrete variations offer significant benefits when used as replacements to conventional concrete. Because of the respective properties of both types of concrete, both economic and environmental benefits are achieved with the use of both. The lower labor costs of SCC and the lower material cost of HVFA lead to …

Transport Of A Methamphetamine Surrogate Through Painted Drywall And Accumulation In Insulation, Nishanthini Vijayakumar Shakila

Masters Theses

"Methamphetamine is a drug of abuse in the United States and it is frequently produced in residential "meth labs." During a specific cooking stage called "salting out", a high concentration of methamphetamine is released into the air and can accumulate on and within indoor surfaces. Even after remediation, methamphetamine and other chemicals can be released into the occupied space by diffusion and desorption from insulation and painted drywall. To better understand the emission characteristics of methamphetamine, the diffusion coefficient of n- isopropylbenzylamine (NIBA; an isomer and surrogate for methamphetamine) was measured in latex painted drywall. To quantify the diffusion coefficient, …

A Novel Membrane Bioreactor Configuration For Nitrogen Removal, Timothy Harrison Canter

Masters Theses

"Population growth in the U.S. and abroad has led to a need for increased treatment of wastewater to limit the effects of additional pollution loadings on bodies of water. Additionally, this need is complicated by limitation on energy inputs. The solution is treatment reactors that are robust, simple to operate, effective in treatment, and energy efficient. This research will compare a traditional membrane bioreactor configuration with a design meant to address these issues.

The proposed configuration used differences in hydraulic head to move liquor from a pre-anoxic zone to the aerobic zone and return a portion of it to the …