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Analysis And Evaluation Of Existing And Novel Turbulent Dynamic Pressure Based Methods For Measuring Bridge Pier And Abutment Scour, Murray Fisher
Analysis And Evaluation Of Existing And Novel Turbulent Dynamic Pressure Based Methods For Measuring Bridge Pier And Abutment Scour, Murray Fisher
All Dissertations
Scour is one of the most significant threats to bridge infrastructure and is the leading cause of failure within the United States. Given this risk to the nation’s transportation infrastructure, it is necessary to understand the development of scour holes around bridge piers and abutments. This can be achieved with scour monitoring, a Federal Highway Administration approved scour countermeasure. As the monitoring techniques available range from simple devices that rest on or in the channel bed to advanced scanning systems that provide a bed contour profile, a concise study of the state of the art in real time scour measurement …
An Error Quantification Methodology For Hurricane Storm Surge Simulations, Bin Pei
An Error Quantification Methodology For Hurricane Storm Surge Simulations, Bin Pei
All Theses
This thesis describes the development of a procedure to quantify errors in hurricane storm surge simulations using a decoupled wind-surge model. The state-of-the-art storm surge simulation program, ADCIRC (Advanced Circulation), and the Georgiou's wind field model were used to simulate the storm surge heights associated with 169 historical hurricanes from 1922 to 2011 along the coast of North Carolina, South Carolina and Georgia. The storm surge modeling errors were quantified by comparing the measured to the simulated annual maximum surge heights at nine water level observation stations maintained by the Center for Operational Oceanographic Products and Services (CO-OPS). The simulated …
An Examination Of The Influence Of Cement Paste On Pervious Concrete Mixtures, Donald Singer
An Examination Of The Influence Of Cement Paste On Pervious Concrete Mixtures, Donald Singer
All Theses
Pervious concrete has many environmental benefits, but with these benefits come additional hurdles unseen in conventional concrete. The main focus of pervious concrete is the maintenance of the interconnected pore structure, leading to porosity values between 15 and 25%, while still developing adequate strength. Due to these inherent properties of pervious concrete, development of a systematic optimum mix design method is challenging. Currently, there is a need to develop a systematic optimum mix design for pervious concrete, but it has yet come to fruition. This research focuses on the influence of cement paste on the performance of pervious concrete, and …
Evaluation Of Rubber Modified Porous Asphalt Mixtures, Kimberly Lyons
Evaluation Of Rubber Modified Porous Asphalt Mixtures, Kimberly Lyons
All Theses
A porous pavement is a type of sustainable pavement that allows stormwater to infiltrate through the pavement into the natural soil bed. Rubber modified binder is the combination of regular asphalt binder mixed with ground crumb rubber, which is derived from used rubber tires by shredding or grinding the tires into small fragments. This research investigated the effects of rubber modified binder on the performance properties of porous asphalt mixtures, which include draindown, porosity, permeability, abrasion resistance, moisture susceptibility, and rutting resistance.
The addition of cellulose fibers has been used to increase the optimum binder content of porous asphalt mix …
Novel Electron Shuttling Compounds, Ramasubramanian Neeraja
Novel Electron Shuttling Compounds, Ramasubramanian Neeraja
All Theses
Electron mediator's usage in remediation technologies might be an excellent alternative to increase the rate of transformation of various contaminants such as nitroamine, polyhalogenated compounds and many others. Employing electron shuttles open up different pathways for the contaminant transformation and the reaction goes to completion at a much faster rate. Anthraquinone-2,6-disulfonate (AQDS) has been known to be a model electron shuttle with good shuttling capacity followed by humic acids. But the necessity for identifying electron shuttles suitable for field applications is important. As remediation technologies will command application of the shuttles on a large scale, tracing shuttles which are cheap, …
Detecting Copper Residues In Sediments From Aquatic Copper-Based Pesticide Applications, Ben Willis
Detecting Copper Residues In Sediments From Aquatic Copper-Based Pesticide Applications, Ben Willis
All Theses
Copper-based algaecides and herbicides are commonly used to mitigate risks of problematic algae and weeds, however there are concerns regarding copper accumulation from treatments. Modeling and laboratory experiments can be used to predict copper accumulation and measurement in sediments, as well as benthic invertebrate responses following treatments. Modeling was used to estimate copper residual concentrations in sediments from algaecide and herbicide treatments. Reported and measured method detection limits (MDLs; minimum concentration of an analyte of interest that can be measured with 99 percent confidence in a specific matrix using an analytical method) were compared to model estimated copper residual concentrations …
Examination Of The Effectiveness Of Bioretention Cells And Porous Paving Practices In Aiken, Sc, Casey Johnson
Examination Of The Effectiveness Of Bioretention Cells And Porous Paving Practices In Aiken, Sc, Casey Johnson
All Theses
This work seeks to quantify the impact and effectiveness of green infrastructure practices, specifically bioretention cells and porous asphalts, for the reduction of peak flow and volume of stormwater that discharges into the headwaters of the Sand River watershed in Aiken, SC. Stormwater runoff flows and volumes were monitored in the upper Sand River watershed that includes the urban Aiken area, along with two nested subwatersheds, prior to, during, and after the construction of the bioretention cells and porous asphalt sites. Flow data from these monitoring stations were analyzed and the data suggested that there was no significant reduction in …
In Situ Ground Freezing And Sampling Of A Pleistocene Sand Deposit In The South Carolina Coastal Plain, Michael Esposito Iii
In Situ Ground Freezing And Sampling Of A Pleistocene Sand Deposit In The South Carolina Coastal Plain, Michael Esposito Iii
All Theses
The procedures used to freeze and sample a Pleistocene sand deposit at the Coastal Research and Education Center near Charleston, South Carolina to preserve and study the effects of diagenesis are presented in this thesis. An initial feasibility study was conducted to target a layer of clean sand at the CREC site with little to no frost heave potential. To freeze the sand deposit, a ground freezing system with a central freezing pipe was installed to target a column of sand 1-m in radius and 2.3-m long. Liquid nitrogen was continuously supplied to the large steel freezing pipe, which was …
3d Reconstruction For Post-Disaster Analysis Of Civil Infrastructure, Joshua Caron
3d Reconstruction For Post-Disaster Analysis Of Civil Infrastructure, Joshua Caron
All Theses
Following a natural disaster, there is a need to rapidly assess the safety of civil infrastructure. This job is typically undertaken by local governments with the help of volunteer civil engineers with structural expertise, as well as organizations such as Cal EMA and ASCE. However, the inspection process is labor-intensive and a bit tedious, and results are prone to error as they tend to rely on the individual expertise of the inspectors. 3D reconstruction stands to become a useful tool in the safety evaluation process, as well as providing valuable opportunities for forensic engineering. This research explores the application of …
Assessment Of Fidelity To Data And Robustness To Uncertainty To Assure Credible Predictions In The Modeling Of Wind Turbine Blades, Kendra Van Buren
Assessment Of Fidelity To Data And Robustness To Uncertainty To Assure Credible Predictions In The Modeling Of Wind Turbine Blades, Kendra Van Buren
All Dissertations
In the field of wind energy, modeling and simulation techniques provide an efficient and economical alternative to experimentation for studying the behavior of wind turbines. Numerical models however are approximations of reality, thusly making it crucial to evaluate various sources of uncertainties that influence the model predictions. Credibility of a numerical model rests on the model's ability to replicate existing experimental data, widely known as fidelity-to-data. This dissertation advocates that fidelity-to-data, while necessary, is insufficient to claim credibility of a numerical model. Herein, the objective is to develop numerical models that not only provide agreement to experimental data, but also …
Analysis Of Energy Savings Through The Use Of Displacement Ventilation In Domestic Buildings, Patrick Daffin
Analysis Of Energy Savings Through The Use Of Displacement Ventilation In Domestic Buildings, Patrick Daffin
All Theses
This study investigates the conditions under which it might be possible to implement a displacement ventilation system in a residential building. An experimental study of the impact on a mechanical air conditioning system of the vertical location of the inlet and outlet vents was performed. The four ventilation configurations of low inlet high outlet, low inlet low outlet, high inlet high outlet, and high inlet low outlet were compared. These four configurations were compared under 13 different heat load scenarios in a full scale instrumented model room. It was found that, for higher heat loads, the low inlet high outlet …
Durability Of Reinforced Concrete Incorporating Crushed Waste Brick As Coarse Aggregate, Matthew Adamson
Durability Of Reinforced Concrete Incorporating Crushed Waste Brick As Coarse Aggregate, Matthew Adamson
All Theses
Using crushed bricks as aggregates in concrete is of particular interest to preserve natural aggregate sources as well as to reduce waste, as it has been estimated that 10% to 30% of all waste in landfills in the united States comes from construction and demolition wastes. By recycling some of these wastes, the sustainability of a project can be improved. However, it is important concrete incorporating these wastes is as durable or more durable then conventional concrete, or will it have a shorter service life. Durability of concrete is its ability to resist deterioration from its external environment such as …
Reverse Osmosis Desalination With Integrated Compressed Air Energy Storage: Conceptual Design And Modeling, Pooja Mahajan
Reverse Osmosis Desalination With Integrated Compressed Air Energy Storage: Conceptual Design And Modeling, Pooja Mahajan
All Theses
Growing fresh water needs have led to an interest in water desalination using reverse osmosis (RO) membranes. Energy consumption has a large share in the expenses incurred to drive a reverse osmosis desalination system. With depleting fossil fuel reserves, tapping renewable sources of energy is a promising alternative to meet the energy requirements. Wind power coupled to an RO desalination system is a potential means of delivering clean water using sustainable energy. This work investigates modeling of a conceptual wind-energy-driven RO desalination system that is made possible because of an air-pressure energy storage mechanism. Bench-scale experiments were performed on an …
Integrated Traffic And Communication Performance Evaluation Of An Intelligent Vehicle Infrastructure Integration (Vii) System For Online Travel Time Prediction, Yongchang Ma, Mashrur Chowdhury, Adel Sadek, Mansoureh Jeihani
Integrated Traffic And Communication Performance Evaluation Of An Intelligent Vehicle Infrastructure Integration (Vii) System For Online Travel Time Prediction, Yongchang Ma, Mashrur Chowdhury, Adel Sadek, Mansoureh Jeihani
Publications
This paper presents a framework for online highway travel time prediction using traffic measurements that are likely to be available from Vehicle Infrastructure Integration (VII) systems, in which vehicle and infrastructure devices communicate to improve mobility and safety. In the proposed intelligent VII system, two artificial intelligence (AI) paradigms, namely Artificial Neural Networks (ANN) and Support Vector Regression (SVR), are used to determine future travel time based on such information as current travel time, VII-enabled vehicles’ flow and density. The development and performance evaluation of the VII-ANN and VII-SVR frameworks, in both of the traffic and communications domains, were conducted, …
Load Carrying Capacity Assessment Of A Masonry Dome, Tun Li
Load Carrying Capacity Assessment Of A Masonry Dome, Tun Li
All Theses
This thesis first establishes a semi-empirical relationship to estimate the reduction in load carrying capacity of a masonry dome due to damage by exploiting deviations in the fundamental natural frequency. A macro finite element model of the dome is developed and calibrated using both non-destructive vibration measurements and destructive load-displacement measurements up to failure. The macro-model is then executed to simulate incremental development of cracks. The first natural frequency and remaining load carrying capacity of the dome are monitored to define a semi-empirical relationship, which is ultimately generalized for spherical domes with varying span-to-height ratios.
Subsequently, in order to numerically …
Numerical And Reliability Analysis Of Gravity Cantilever Retaining Walls Backfilled With Shredded Tires Subjected To Seismic Loads, Eleanor Huggins
Numerical And Reliability Analysis Of Gravity Cantilever Retaining Walls Backfilled With Shredded Tires Subjected To Seismic Loads, Eleanor Huggins
All Theses
Shredded tires have been considered as a suitable alternative to conventional sand and gravel backfill materials as they offer benefits from their significantly lower unit weight, reductions in the cost of materials and construction, and because they utilize a common and potentially hazardous waste material. This research addresses some gaps in previous research in the implementation of shredded tires in this capacity by examining variation in material properties through a reliability analysis, developing an improved design technique for retaining walls tailored to shredded tire fills, and simulating how shredded tire backfill behaves in conjunction with retaining walls when subject to …
The Effect Of Granular Activated Carbon Pretreatment And Sand Pretreatment On Microfiltration Of Greywater, David Christopher
The Effect Of Granular Activated Carbon Pretreatment And Sand Pretreatment On Microfiltration Of Greywater, David Christopher
All Theses
Around the world, water scarcity is driving people to practice water reuse. One form of water reuse is the recycling of greywater, which is household wastewater excluding toilet waste. With adequate treatment, greywater may be recycled onsite for applications that do not require potable water, such as irrigation or toilet flushing. Membrane filtration (including microfiltration (MF)) is one option for greywater treatment. The small footprint, modular nature, and predictable performance of MF make it an attractive option. However, direct MF of greywater can lead to rapid membrane fouling. This thesis investigated two possible pretreatments for reducing membrane fouling and improving …
Biomass And Lipid Production From Heterotrophic And Mixotrophic Fed-Batch Cultivations Of Microalgae Chlorella Protothecoides Using Glycerol, Shwetha Sivakaminathan
Biomass And Lipid Production From Heterotrophic And Mixotrophic Fed-Batch Cultivations Of Microalgae Chlorella Protothecoides Using Glycerol, Shwetha Sivakaminathan
All Theses
Chlorella protothecoides is a microalga that can grow both photo-autotrophically and/or heterotrophically under different culture and environmental conditions. In this study both the heterotrophic growth and mixotrophic growth have been conducted. The heterotrophic experiments were conducted completely in the dark while the mixotrophic experiments had the dark cycles with periodic light exposure. The aim of the study was to independently understand the effect of each mode on biomass and lipid yields.
For the heterotrophic experiments, glycerol was used as an external organic carbon source while yeast extract was used as the nitrogen source. The carbon and nitrogen source were added …
Functionalized Nanoparticles As Removable Coatings For Reverse Osmosis Membranes, Megan Smith
Functionalized Nanoparticles As Removable Coatings For Reverse Osmosis Membranes, Megan Smith
All Theses
Reverse osmosis (RO) desalination is increasingly used to produce potable water throughout the world. Despite their promising abilities, membrane filtration processes are limited by fouling. Fouling is a broad term for organics, inorganics, colloids and organisms that interact physically, chemically, or biologically with the membrane surface, resulting in reduced flux and shortened membrane lifespan. There is potential to create a snakeskin-like barrier between the membrane and foulants by electrostatically binding a coating material to the membrane that can be released by pH manipulation, removing foulants in the process. The feasibility of using functionalized nanoparticles as removable adsorptive coatings on RO …
A Laboratory Study Of Levee Scour From Overtopping Storm Waves And Protection For Robust Desgins, Earnest Johnson
A Laboratory Study Of Levee Scour From Overtopping Storm Waves And Protection For Robust Desgins, Earnest Johnson
All Theses
Levee failure due to scouring has been a prominent occurrence among intense storm surges and waves, giving rise to the implementation of various scour protection measures over the years. Several experiments were performed on a model levee on either bare levee soil or with a scour protection measure covering the soil. The purpose of this study is to breakdown the dynamics of levee scour due to overtopping waves and suggest efficient methods in reducing the amount of scour. The levee soil was made up of a sand-clay mixture and placed in a laboratory wave tank that created a constant wave …
Evaluation Of Dichloromethane As An Electron Donor For Reductive Dechlorination Of Tetrachloroethene To Ethene, Yogendra Kanitkar
Evaluation Of Dichloromethane As An Electron Donor For Reductive Dechlorination Of Tetrachloroethene To Ethene, Yogendra Kanitkar
All Theses
Tetrachloroethene (PCE) and trichloroethene (TCE) are the predominant contaminants at hazardous waste sites in the United States. Although less prevalent, dichloromethane (DCM) is also found at a number of sites. EPA classifies PCE and DCM as likely to be carcinogenic in humans by all routes of exposure, while TCE is classified as carcinogenic to humans by all routes. At some sites, releases of PCE, TCE and DCM comingle in the groundwater. Field evidence from one such site in California suggests that DCM is used as the electron donor for reductive dechlorination of TCE. Nevertheless, definitive evidence that DCM can serve …
Historical Integration Of Remote Sensing Data: Can Gis Extract Information From Grayscale Aerial Photographs?, Kristina Robertson
Historical Integration Of Remote Sensing Data: Can Gis Extract Information From Grayscale Aerial Photographs?, Kristina Robertson
All Theses
There have been many changes in land management policies of the National Forest system over the past 100 years. Changes in policy related to law, population growth and economics directly cause changes in land cover. Global land cover changes are occurring at such a pace and magnitude that they are affecting Earth system functioning (Lambin et al., 2001). The analysis of land cover changes plays a key role in understanding several environmental phenomena, resulting in a need for objective and comparable land cover maps (Gennaretti et al., 2011). Advances in remote sensing and Geographic Information Systems (GIS) have modernized land-use …
Laboratory Characterization And Theoretical Analysis Of Contaminant Mass Transfer, Xiaoling Liu
Laboratory Characterization And Theoretical Analysis Of Contaminant Mass Transfer, Xiaoling Liu
All Dissertations
Chlorinated volatile organic compounds (CVOCs) in fractured, low permeability material can be a long-term source of groundwater contaminants and they are among the most difficult remediation challenges. Thermal methods are a possible remediation option, where heat is used to boil water and the volatile compounds are stripped out by partitioning into the resulting water vapor. Theoretical analysis indicates that only a small fraction of pore water removal may lead to a significant geometric reduction in the dissolved concentration [(Udell(, 1998]. Previous modeling studies [(Falta and Murdoch(, 2011; (Pruess(, 1983] suggest that a lower permeability limit exists for effective mass transfer …
Assessing Anaerobic Bio-Oxidation Of Vinyl Chloride And Ethene, Ademola Bakenne
Assessing Anaerobic Bio-Oxidation Of Vinyl Chloride And Ethene, Ademola Bakenne
All Theses
Perchloroethene (PCE) and trichloroethene (TCE) are two of the most commonly used chlorinated solvents around the world. These compounds and their dechlorination daughter products have become the most prevalent organic contaminants found in a majority of hazardous waste sites in the United States. Since implementation of traditional remediation methods would cost hundreds of billions of dollars, there has been tremendous interest in bioremediation as a low cost alternative to achieving remedial goals. Anaerobic reductive dechlorination is the most prevalent form of bioremediation in most locations. The ultimate daughter products from reductive dechlorination of PCE and TCE are ethene and ethane, …
Developing A Greenhouse Gas Emissions Calculation Tool For Water Utilities, Anthony Hampton Johnston
Developing A Greenhouse Gas Emissions Calculation Tool For Water Utilities, Anthony Hampton Johnston
All Theses
The issue of climate change has led to an increased emphasis on sustainable practices in almost every facet of our lives. For water utilities, this has increased scrutiny on energy use. Although traditionally viewed solely in financial terms, energy use is also the primary source of greenhouse gas (GHG) emissions from water utilities. The emerging concern over GHG emissions coincides with potential federal legislation and regulation by the Environmental Protection Agency (EPA). In order for water utilities to determine their GHG emissions, guides and tools must be made readily available. Information to educate water utilities about their GHG emissions is …
Resource Allocation Framework: Validation Of Numerical Models Of Complex Engineering Systems Against Physical Experiments, Joshua Hegenderfer
Resource Allocation Framework: Validation Of Numerical Models Of Complex Engineering Systems Against Physical Experiments, Joshua Hegenderfer
All Dissertations
An increasing reliance on complex numerical simulations for high consequence decision making is the motivation for experiment-based validation and uncertainty quantification to assess, and when needed, to improve the predictive capabilities of numerical models. Uncertainties and biases in model predictions can be reduced by taking two distinct actions: (i) increasing the number of experiments in the model calibration process, and/or (ii) improving the physics sophistication of the numerical model. Therefore, decision makers must select between further code development and experimentation while allocating the finite amount of available resources. This dissertation presents a novel framework to assist in this selection between …
Deviations In Standard Aggregate Gradation And Its Affects On The Properties Of Portland Cement Concrete, Marcus Balitsaris
Deviations In Standard Aggregate Gradation And Its Affects On The Properties Of Portland Cement Concrete, Marcus Balitsaris
All Theses
Aggregate gradation is the particle size distribution of both the stone and sand present in the concrete matrix. It is an aggregate property that has been heavily researched for over a century but the effects of which on concrete properties is still somewhat misunderstood. Past research has revealed that aggregate gradation dictates the proportion of aggregate to cement paste in concrete, and can play a major variable that determines the overall durability of the construction material. Increasingly, aggregate in South Carolina are failing to meet the standard aggregate gradation for portland cement concrete, however, the effects of such failed aggregate …
Application Of Microbial Fuel Cells In A Forested Wetland, Jianing Dai
Application Of Microbial Fuel Cells In A Forested Wetland, Jianing Dai
All Theses
ABSTRACT
Electricity can be generated from forest residues, especially the organic matter from litter fall, in freshwater forested wetland environments with a microbial fuel cell (MFC) system. Electricity generation efficiency was examined for cypress, tupelo, and pine litter extracts, using dual-chamber reactors. The maximum power density generated with cypress extracts was on the level of 320 mW/m2, higher than tupelo (230 mW/m2), and pine (210 mW/m2). The efficacy of cypress extracts was also higher than tupelo and
pine, demonstrating that organic matter from cypress litter is a preferred substrate for electricity generation with MFCs. Meanwhile, low aromaticity of the substrate …
Evaluation Of An Enrichment Culture That Reductively Dechlorinates Γ-Hexachlorocyclohexane, Christina Anderson
Evaluation Of An Enrichment Culture That Reductively Dechlorinates Γ-Hexachlorocyclohexane, Christina Anderson
All Theses
In a previous study using microcosms from a site contaminated with γ- hexachlorocyclohexane (γ-HCH), rapid anaerobic biodegradation of γ-HCH to benzene and chlorobenzene was observed. Enrichment cultures were developed and subsequently transferred to an anaerobic sulfate-free HEPES buffered medium without loss of γ-HCH dechlorination, thus suggesting γ-HCH undergoes anaerobic biodegradation via chlororespiration. The overall objective of this thesis was to further characterize the enrichment culture.
To do so, one specific objective was to determine the effect of vancomycin on γ-HCH in an enrichment culture grown in a sulfate-free HEPES buffered medium using hydrogen as the electron donor. This objective would …
Remote Detection Of Ephemeral Wetlands In Mid- Atlantic Coastal Plain Ecoregions: Lidar And High-Throughput Computing, Paul Leonard
Remote Detection Of Ephemeral Wetlands In Mid- Atlantic Coastal Plain Ecoregions: Lidar And High-Throughput Computing, Paul Leonard
All Theses
Ephemeral wetlands are ecologically important freshwater ecosystems that occur frequently throughout the Atlantic coastal plain ecoregions of North America. Despite the growing consensus of their importance and imperilment, these systems historically have not been a national conservation priority. They are often cryptic on the landscape and methods to detect ephemeral wetlands remotely have been ineffective at the landscape scales necessary for conservation planning and resource management. Therefore, this study fills information gaps by employing high-resolution light detection and ranging (LiDAR) data to create local relief models that elucidate small localized changes in concavity. Relief models were then processed with local …