Engineering Commons^™

Metalloporphyrin Catalyzed Degradation Of Pce: Effects Of Reductants, Buffers And Cosolvent Concentration, Sowmya Suryanarayanan

All Theses

Reductive dechlorination of chlorinated organic contaminants using metalloporphyrins as catalysts may be an effective approach to treat widespread contamination. However, most previous studies have examined water-soluble rather than insoluble metalloporphyrins despite the fact that the latter category makes up the largest fraction found in nature. Recent studies have shown that addition of different cosolvents to water can activate otherwise non-reactive metalloporphyrin catalysts and facilitate the reduction of tetrachloroethylene (PCE), presumably by the mere process of making the otherwise insoluble metalloporphyrins dissolve in solution. Therefore, solubility has been advanced as a key factor in the ability of metalloporphyrins to catalyze organic …

Evaluation Of A Computer Vision Traffic Surveillance System, Robert Graham

All Theses

This thesis presents an evaluation of the accuracy of a novel computer vision traffic sensor - developed by the Clemson University Electrical and Civil Engineering Departments - capable of collecting a variety of traffic parameters. More specific, the thesis examines how the camera height and distance from the travel way affects the accuracy. The details of the quantitative and qualitative evaluations used to validate the system are provided. The parameters chosen to evaluate were volume, vehicle classification, and speed. Experimental results of cameras mounted at heights of 20 and 30 feet and a lateral distance of 10 and 20 feet …

Bacterial Auto-Aggregation And Co-Aggregation In Activated Sludge, Fei Chen

All Theses

Microbial auto-aggregation and co-aggregation, leading to biofilm or floc formation, widely occur in natural systems. This study was conducted to investigate the extent of bacterial auto-aggregation and co-aggregation in activated sludge and their contributions in activated sludge floc formation. In this study, an activated sludge sample was separated into a supernatant part (planktonic community) and a sediment part (floc community) by centrifugation at 650_g for 2 minutes. 197 strains were isolated from both communities. These isolates belong to 18 phylotypes based on molecular identifications. Similar phylogenetic distributions of these isolates were observed in planktonic and floc communities, suggesting a similar …

Laboratory Evaluation Of Microbial Aggregation In Activated Sludge, Xiaoling Liu

All Theses

Microbial aggregation was investigated in this study using the activated sludge process as a model system, the performance of which is highly dependent on effective bioaggregation. This research includes two experiments. First, four laboratory-scale activated sludge sequencing batch reactors (SBRs) were constructed in order to evaluate the effect of solids retention time (SRT) on microbial aggregation. These SBRs were operated at SRT of 4, 8, 16, and 32 days, respectively, fed with a protein-based synthetic wastewater, and monitored over a period of 268 days for performance and sludge settling characteristics including soluble COD in the effluent (sCOD), sludge volume index …

Cosolvent Effects On The Reductive Dechlorination Of Tetrachloroethylene Catalyzed By Iron Tetraphenyl Porphyrin Chloride, Lavanya Ramasubramanian

All Theses

Abiotic electron transfer mediated reductive dechlorination reactions have been studied extensively in the past decade. Porphyrins and metalloporphyrins are common electron transfer mediators used. Past studies have shown that some metalloporphyrins play a key role in increasing the rate of reaction in the presence of cosolvents. There have also been suggestions that organic cosolvents enhance the rate of reduction by increasing the solubility of metalloporphyrins.
The primary objective of this project was to examine the effect of cosolvents on the metalloporphyrin-catalyzed reductive dechlorination of tetrachloroethylene (PCE). Subsequently, experiments were also conducted to test the hypothesis that metalloporphyrin solubility is linked …

Assessing Asr Potential Of Hardened Concrete And The Use Of Rice Husk Ash To Mitigate Asr, David Wingard

All Theses

This two part research study was created to first develop a new process using existing test methods to determine the Alkali-Silica Reaction (ASR) potential of hardened concrete that is exposed to external alkalis and secondly to determine the ASR mitigation potential of using rice husk ash (RHA) as a supplementary cementitious material (SCM). The first part of the research study was completed by using a new aggregate extraction procedure that uses a combination of hydrochloric acid treatments and abrasion to remove the cement paste from the aggregate. This extracted aggregate was then crushed down to the specified sizes and used …

Seismic Fragility Curves For A Typical Highway Bridge In Charleston, Sc Considering Soil-Structure Interaction And Liquefaction Effects, Matthew Bowers

All Theses

Evidence from historical earthquakes suggests that the vulnerability of highway bridges is significantly affected by large permanent ground deformations caused by liquefaction as well as soil-structure interaction (SSI). The vulnerability of a typical multi-span simply-supported (MSSS) concrete girder bridge found in Charleston, South Carolina, is evaluated with consideration for liquefaction and SSI effects. In general, existing bridges in this region were not originally designed with consideration for seismic events or liquefaction of underlying soils. Fragility curves that represent the probability of exceeding predefined performance levels of damage given an earthquake of a particular intensity are used to evaluate the effects …

Investigation Into Mitigation Of Alkali-Silica Reaction Using Selected Scms In Presence Of Potassium Acetate Deicer, Jigar Desai

All Dissertations

Alkali-silica reaction (ASR) is one of the most recognized durability problems in concrete leading to premature deterioration of different types of concrete structures. Recent investigation into premature deterioration of airfield concrete pavements indicated the aggressive effects of alkali-acetate and alkali-formate based deicers on concrete containing marginal aggregates, in particular on their potential to induce ASR.. This dissertation presents the results and analysis from a research study conducted to evaluate the effectiveness of selected supplementary cementitious materials-SCMs (fly ash and slag) as ASR mitigation measures in presence of potassium acetate based deicer.
Five aggregates that encompass a range of mineralogies and …

Sediment Transport Upstream Of Orifices, David Powell

All Dissertations

Sediment transport upstream of orifices has not been studied outside the realm of the restoration of reservoir storage capacity. This experimental study used a large basin with a circular orifice outlet and a movable sand bed leveled with the invert of the orifice. Three sizes of non-cohesive, uniform sand were used with d₅₀ values of 0.29mm, 0.72mm, and 0.89mm. Bed profiles at equilibrium scour conditions were measured for three different head levels for each sediment size. The maximum scour depth, length, and scour width were related to the particle size and the available head. The longitudinal and lateral extents …

Tubería Petrolera Recurso Para La Construcción De Puentes, Diego Armando Leal Vargas, Wilmar Armando Jiménez Marulanda, Anderson Salvador Bernal Tello

Ingeniería Civil

No abstract provided.

A Pilot Study On The Effects Of Temperature On The Material Properties Of Prestressed Concrete And The Use Of Thermogravimetric Analysis In The Assessment Of Heat-Affected Concrete, Kacie Caple

All Theses

An understanding of the material property changes in building materials due to exposure to a fire is needed for accurate damage assessment of a structure. Discussion pertaining to material property changes and the bond between concrete and prestressing steel following elevated temperature exposures is presented. Evaluation of the use of thermogravimetric analysis (TGA) as a post-fire analysis tool to determine the maximum temperature exposure of concrete is also included.
Heated concrete cylinders were tested to determine the compressive strength and modulus of elasticity changes of concrete. Heated steel prestressing strands were tested in tension to determine changes in the ultimate …

Experimental And Analytical Application Of The Hodd Method For The Detection Of Damage, Jacob Merkley

All Theses

Detecting damage location and severity in civil engineering structures has become an important research topic in the past several decades. Various non-destructive damage identification methods using dynamic properties from ambient and forced vibration have been developed. Researchers have shown that higher order derivatives of mode shapes of the 2nd and 4th order can be effective in detecting damage in civil engineering structures. Furthermore, these higher order derivatives are sensitive to small changes in global stiffness facilitating the detection of small degrees of damage.
In this study a modal analysis is performed on analytical and experimental simply supported beams using the …

Energy Efficiency In Cold-Weather High-End Custom Homes, Joseph R. Kearl

Theses and Dissertations

Nationally, there is increasing interest in energy efficient homes due to growing energy costs and increased awareness. However, many builders haven't yet incorporated energy saving products and practices into homes. Many builders don't have the resources to evaluate available options and prefer to rely on the experiences of other builders. The purpose of this study was to create energy efficiency benchmarks for cold-weather, high-end custom homes and evaluate current building practices. A list of energy-efficient products and practices was created through a review of relevant literature. A group of expert builders was formed into a committee to help determine energy …

Sensitivity Of Half-Cell Potential Measurements To Properties Of Concrete Bridge Decks, Thad Marshall Pinkerton

Theses and Dissertations

Half-cell potential testing has been recommended as a non-destructive method for assessing the corrosion potential of reinforcing steel in concrete bridge decks. The technique is particularly useful because it can be utilized to evaluate the probability of corrosion before damage is evident at the surface of a bridge deck. The specific objective of this research was to quantify the effects of age, chloride concentration, concrete cover thickness, spatial position, temperature, and presence or condition of epoxy coating on half-cell potential measurements of concrete bridge decks typical of those in Utah. The laboratory testing associated with this research followed a full-factorial …

Mexico Engineering Study Abroad: Assessing The Effectiveness Of International Experiences On Teaching Global Engineering Skills, Joshua Benjamin Draper

Theses and Dissertations

Globalization is a rapidly increasing trend in many industries, including civil engineering. This paper defines the skills engineers will need in an increasingly international industry. It also describes an engineering study abroad program designed to teach some of those skills to students and presents a survey used as an assessment tool to evaluate the effectiveness of the program. The program, called Mexico Engineering Study Abroad (MESA), is taught at Brigham Young University (BYU) in Provo, UT. MESA is a project-based extended field trip format class that couples hydrologic modeling with cultural awareness as students work together with Mexican students on …

Dry Stacked Surface Bonded Masonry - Structural Testing And Evaluation, Eric B. Murray

Theses and Dissertations

The ENDURA block system is a dry-stack surface-bonded masonry system. Typical masonry construction uses thin-set mortar in the bed joints to provide a bearing surface for the blocks while the ENDURA system typically relies on shims and a surface bonding coat to ensure that the wall is level and plumb and to provide stability. Typical ENDURA block walls are built with the reinforcement placed eccentrically in the walls. Testing was performed on ten walls in order to determine axial capacity. The walls were ten feet high by eight feet wide. Each of the walls was built using a different configuration …

Time And Frequency Domain Analyses Of Hydrologic And Stream Water Quality Data, Shesh Raj Koirala

Doctoral Dissertations

The issue of scaling of deterministic properties at various domain levels has become an area of interest for active research. Interpretation of observational data, and similarly hydrologic simulation, require an understanding of how certain deterministic modeling parameters scale from the smaller to larger domains spatially and temporally. Novel approaches to better understand scaling behavior in hydrologic systems and that will result in improved deterministic modeling are necessary to advance the state-of-the-science in hydrologic transport processes, particularly in the areas of microbial concentration and inorganic chemical constituent dynamics. Two primary objectives of this research were i) to determine the statistical relationship …

Evaluation Of Impacts On Delay, Cycle-Length Optimization, Control Types, And Peak-Hour Factor With The Randomness Of Traffic, Jan-Mou Li

Doctoral Dissertations

Some basic concepts about traffic which are correct in theory may be misinterpreted in practice. Such misinterpretations may lead to a different direction from the ideal operation. This four-part dissertation is designated to examine fundamental concepts in traffic operation, and to validate the impact of randomness on control delays, cycle-length optimization, control types, and the peak-hour factor.

Control delays experienced by drivers is a critical performance measure on interrupted-flow traffic which involves movements at slower speeds and stops on intersection approaches, as vehicles move up in the queue or slow down upstream of an intersection. Since the basic term of …

The Development Of Regional Regression Equations For Flood Flow Estimates Of Ungauged Streams In The State Of Arkansas, Stephen Mccall

Civil Engineering Undergraduate Honors Theses

No abstract provided.

Validation Of Adaptive Aeroelastic Finite Element Program For Two Dimensional Flow Past A Suspension Bridge Girder Section Using Unstructured Grids., Shanique Murray

Civil Engineering Undergraduate Honors Theses

No abstract provided.

Performance Based Contracting And Improving The Current Contracting Process, Troy Berkland

All Theses

The primary objective of the research described in this report was to suggest improvements to the maintenance contracting process currently utilized by the South Carolina Department of Transportation (SCDOT). A secondary research objective was to examine to what extent SCDOT could migrate more toward performance based, as opposed to method based, highway maintenance specifications.
A comprehensive literature review indicated some states had successfully implemented performance based specifications for a wide range of maintenance activities whereas others had not. Some states have adopted performance based specifications as part of a comprehensive asset management program whereby the contractor typically performs all routine …

Vulnerability Of Shallow Aquifers Of The Conterminous United States To Nitrate: Assessment Of Methodologies, Karthik Kumarasamy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Groundwater is an important natural resource for numerous human activities, accounting for more than 50% of the total water used in the United States. Groundwater is vulnerable to contamination by several organic and inorganic pollutants such as nitrate, heavy metals, and pesticides. Assessment of groundwater vulnerability aids in the management and protection of limited groundwater resources.

The focus of this thesis is to (1) statistically compare two groundwater vulnerability assessment models; modified DRASTIC (Acronym for Depth to water, net Recharge, Aquifer media, Soil media, Topography, Impact of vadose zone, and hydraulic Conductivity of aquifer) and ordinal logistic regression for NO …

Characterizing Groundwater-Surface Water Interactions In Great Smoky Mountains National Park Using Hydrologic, Geochemical & Isotopic Data, Amanda Marie Mckenna

Masters Theses

Groundwater-surface water interactions can substantially influence the quality of surficial water bodies and are thus important when investigating ecological health of and climate change impacts on an area. However, data collection can be hindered when the location is remote and/or legally protected. This paper presents a methodology to implement minimallyinvasive field techniques at a remote and protected location that allows preliminary identification of the relationship between groundwater and surface water. Great Smoky Mountains National Park was selected as the study area as it is subjected to some of the highest rates of acid deposition in the country. Ecological damage is …

Using Multivariate Analysis Of Geochemical Data To Better Define Hydrologic Interfaces In Surface Water - Groundwater Systems, Candice Ann Owen

Masters Theses

Groundwater-surface water interactions have been shown to be important to flow generation and stream chemistry in upland catchment environments. These areas, however, are often difficult to access making the implementation of standard hydrological surface and subsurface monitoring equipment and characterization procedures impractical, arduous and in many cases impossible due to the nature of the terrain and also regulatory guidelines for protected areas. By collecting surface water samples at distinct water contribution sites to a headwater stream, areas of groundwater influence were inferred and a hydrochemical conceptual model of a small basin was created.

The objectives of this research were to …

Blast Resistant Design Of Steel Structures, Sarah Beth Janney

Masters Theses

The purpose of this study was to examine the load experienced by a steel blast cubicle from a surface blast test. An important objective was to determine the blast load experienced at different standoff distances and the blast resistance capability of the blast cubicle. Three cubicles with standoff distances of 20, 25, and 30ft respectively were simultaneously subjected to a 50lb TNT explosive. The manual Structures to Resist the Effects of Accidental Explosions, Army TM 5-1300 conservatively predicted the blast pressure loadings obtained from the pressure transducers mounted on the cubicles. Data collected from accelerometers was compared to results from …

Modeling Streambed Heating In Shallow Streams, Robert Leslie Annear Jr.

Dissertations and Theses

The Oregon Department of Environmental Quality is developing Total Maximum Daily Loads to address water quality concerns and threatened and endangered species habitat requirements. Approximately 940 water body segments are listed as water quality limited for temperature in Oregon. CE-QUAL-W2 Version 3 is a two-dimensional water quality and hydrodynamic model capable of modeling rivers, reservoirs and estuaries. An important aspect of modeling stream temperature is handling the short-wave solar radiation that penetrates the water surface and impacts the streambed, which can affect water temperatures under low-flow conditions. The Bull Run River-Reservoir system is a 264 km2 watershed 42 km east …

Shear Modulus Degradation Of Liquefying Sand: Quantification And Modeling, Peter A. Olsen

Theses and Dissertations

A major concern for geotechnical engineers is the ability to predict how a soil will react to large ground motions produced by earthquakes. Of all the different types of soil, liquefiable soils present some of the greatest challenges. The ability to quantify the degradation of a soil's shear modulus as it undergoes liquefaction would help engineers design more reliably and economically. This thesis uses ground motions recorded by an array of downhole accelerometers on Port Island, Japan, during the 1995 Kobe Earthquake, to quantify the shear modulus of sand as it liquefies. It has been shown that the shear modulus …

Effect Of Beam Splicing On Seismic Response Of Buckling-Restrained Braced Frames, Gary S. Prinz

Theses and Dissertations

The deformation capacity of typical buckling-restrained braced frames (BRBFs) is limited by the rotation capacity of connecting regions. The rotation capacity of the connection region is limited by fracture of the gusset welds and yielding in the beams and columns. A different connection detail with beam-splices outside the gusset has been shown to increase connection rotation capacity when compared to typical connections, in a few component tests. This study expands upon the performed component tests, by analyzing the beam splice connection at the system level under directional dynamic loads. Finite element analysis and dynamic loads are used to analyze two …

Caracterización Geomecánica De Mezclas De Suelos Para Modelos Físicos Por El Método De Materiales Equivalentes, Camilo Andres Sarmiento Forero, Harold David Vidal Rovira

Ingeniería Civil

No abstract provided.

Medición Experimental Del Coeficiente De Presión Lateral De Tierras En Reposo Usando El Consolidómetro De Rowe Y Modelos Constitutivos, Edwin Mauricio Alfonso Maldonado, José Mauricio Pardo Romero, Fernando Augusto Urrego Cuellar

Ingeniería Civil

No abstract provided.