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Full-Text Articles in Engineering

Cost And Embodied Energy Optimization Of Rectangular Reinforced Concrete Beams, Alexander Kosloski Dec 2013

Cost And Embodied Energy Optimization Of Rectangular Reinforced Concrete Beams, Alexander Kosloski

All Theses

Concrete has a large environmental footprint so it is desirable to find ways to efficiently design structural members. Engineers can exercise their abilities early on in the design phase of construction projects to reduce the environmental footprint by minimizing the amount of materials required. One way to achieve these results is to optimize the design of structural concrete. In this study, simple-span rectangular reinforced concrete (RC) beams with a range of different bending moments were analyzed. The primary goal was to combine life cycle analysis (LCA), numerical optimization, and reinforced concrete mechanics to create a framework for designing efficient RC …


Twelve Mile Creek Channel Morphology, Substrate Composition, And The Macroinvertebrate Community Changes Resulting From Multiple Dam Removals, Patricia Whitener Dec 2013

Twelve Mile Creek Channel Morphology, Substrate Composition, And The Macroinvertebrate Community Changes Resulting From Multiple Dam Removals, Patricia Whitener

All Theses

Dam removal is gaining global attention as a potential restoration tool for impacted rivers. As the practice of dam removal increases, physical, chemical and biological monitoring before and after dam removal is essential to our understanding of the ecological consequences of this type of disturbance. Under the Lake Hartwell Restoration and Compensation Determination Plan, two dams (>9 m height) were removed from the Twelve Mile Creek watershed (170 km2) in Pickens county, South Carolina. To assess the short term impacts of dam removal on the Twelve Mile Creek ecosystem we conducted biomonitoring of macroinvertebrate species and surveys of river …


Dissolved Carbon Dioxide For Scale Removal In Reverse Osmosis, Erin Partlan Dec 2013

Dissolved Carbon Dioxide For Scale Removal In Reverse Osmosis, Erin Partlan

All Theses

Membrane fouling is a major operational issue in reverse osmosis (RO) desalination plants. In particular, plants treating brackish groundwater can encounter troublesome inorganic scales, including carbonates, sulfates, and silicates. A novel cleaning method is proposed to remove inorganic scales from fouled RO membranes usinag dissolved CO 2 . As CO2 molecules encounter membrane foulants, the surfaces serve as nucleation sites for small bubbles to form and shear off foulants. Dissolved CO2 solutions were prepared by bubbling CO2 gas into water held in a pressure vessel. Gas dissolution was confirmed by enhanced exit velocities for water containing CO …


Mechanistic Characterization Of Rubberized Asphalt Mixture And Design Using Full Scale Tire-Pavement Finite Element Modeling, Sajib Saha Dec 2013

Mechanistic Characterization Of Rubberized Asphalt Mixture And Design Using Full Scale Tire-Pavement Finite Element Modeling, Sajib Saha

All Theses

Rubberized half-warm mix asphalt (HWMA) is being considered as one of the promising and sustainable solutions to the current environmental and economic crisis of asphalt industry. A fully mechanistic characterization and performance analysis of this mixture subjected to realistic loading and temperature conditions is necessary before its application in a practical pavement structure. The objective of this research is to characterize the viscoelastic properties of rubberized HWMA at different temperatures and to develop and validate a finite element model of a tire-pavement structure. In this research, a generalized Maxwell model is chosen to represent the time dependent stress-strain behavior of …


Rapid Riparian Buffer Width And Quality Analysis Using Lidar In South Carolina, Emre Akturk Dec 2013

Rapid Riparian Buffer Width And Quality Analysis Using Lidar In South Carolina, Emre Akturk

All Theses

The importance of protecting water quality and aquatic resources are increasing because of harmful human impacts within and around waterways. Establishing or restoring functional riparian areas protect water quality and are a good mechanism to conserve aquatic systems, plants, and wildlife. Laser-based remote sensing technology offers a high resolution approach to both characterize and document changes in riparian buffer zones (RBZs). The objectives of this study were to build a model to calculate riparian buffer width on both sides of a stream using a LiDAR-derived slope variable, to classify riparian buffers and determine their quality, and to evaluate the appropriateness …


Safety And Operational Characteristics Of Lane Widths On Urban And Rural Roadways A Simulator Study, Meredith Ladue Dec 2013

Safety And Operational Characteristics Of Lane Widths On Urban And Rural Roadways A Simulator Study, Meredith Ladue

All Theses

The primary goal for this study was to further evaluate and assess the effect of lane width on the safety and operation of roadways in South Carolina. Due to various site conditions that affect the safety and operations of roadways, highway design engineers often face many challenges when developing appropriate road design standards. To investigate specific site conditions for the South Carolina Department of Transportation (SCDOT) a research study took place. In 2011, Part 1 of this research included field studies conducted by Kevin Baumann and Trey Jordan. Due to the various limitations of the field studies it was evident …


Optimal Retrofit Strategy Design For Highway Bridges Under Seismic Hazards: A Case Study Of Charleston, Sc, Shawn Parmelee Dec 2013

Optimal Retrofit Strategy Design For Highway Bridges Under Seismic Hazards: A Case Study Of Charleston, Sc, Shawn Parmelee

All Theses

A significant number of US highway bridges are inadequate for seismic loads and could be seriously damaged or collapse during a relatively small earthquake. On the most recent infrastructure report card from the American Society of Civil Engineers (ASCE), one-third of the bridges in the United States are deemed to be structurally deficient. To improve this situation, at-risk bridges must be identified, evaluated, and effective retrofitting programs implemented to reduce their seismic vulnerabilities. In practice, the Federal Highway Administration uses the expected damage method and indices method to assess the condition of bridges. These methods compare the severity of expected …


Evaluating The Predictive Capability Of Numerical Models Considering Robustness To Non-Probabilistic Uncertianty In The Input Parameters, Parker Shields Dec 2013

Evaluating The Predictive Capability Of Numerical Models Considering Robustness To Non-Probabilistic Uncertianty In The Input Parameters, Parker Shields

All Theses

The paradigm of model evaluation is challenged by compensations between various forms of errors and uncertainties that are inherent to the model development process due to, for instance, imprecise model input parameters, scarcity of experimental data and lack of knowledge regarding an accurate mathematical representation of the system. When calibrating model input parameters based on fidelity to experiments, such compensations lead to non-unique solutions. In turn, the existence of non-unique solutions makes the selection and use of one `best' numerical model risky. Therefore, it becomes necessary to evaluate model performance based not only on the fidelity of the predictions to …


Evaporation And Modeling Water Availability In The Savannah River Basin, Ryne Phillips Dec 2013

Evaporation And Modeling Water Availability In The Savannah River Basin, Ryne Phillips

All Theses

Four methods for estimating lake evaporation are presented and compared. Three are mass transfer methods that incorporated high resolution satellite imagery obtained from the MODIS sensor on the Terra and Aqua satellites. The fourth is the traditional pan method, which used monthly derived pan coefficients and pan evaporation measurements from a Class A evaporation pan located in Clemson, SC.

The four evaporation methods were used to estimate lake evaporation from the five major lakes in the Savannah River Basin for a period of more than one decade. Analysis of the evaporation rates clearly illustrated the uncertainty in daily, monthly, and …


Chemical, Physical, And Moisture Release Characteristics Of Compost Based Potting Media, Tianzhen Wang Dec 2013

Chemical, Physical, And Moisture Release Characteristics Of Compost Based Potting Media, Tianzhen Wang

All Theses

A commercially available composted cow manure was used as a potting media amendment. A common base mix for woody ornamentals of 8 parts pine bark and 1 part sand was compared with 3 other mixes that contained 20%, 30%, and 40% compost (v/v). The remaining fraction of these three mixes was the base mix (bark and sand). Samples of the pine bark and compost were analyzed to determine the following plant nutrients and mineral concentrations: nitrogen (organic and soluble), carbon, P2O5, K2O, Ca, S, Mg, Mn, Cu, Zn, Na, Fe, and Al.


Effect Of Differential Movement Of Straight Reinforcing Bars During Early Age Curing On The Bond Strength, Tyler Andrews Aug 2013

Effect Of Differential Movement Of Straight Reinforcing Bars During Early Age Curing On The Bond Strength, Tyler Andrews

All Theses

As the nation's infrastructure continues to age, the number of structural deficiencies is rising. Accordingly, there is a great need and desire to replace these failing components in a quick and efficient fashion. Prefabricated elements for structures such as bridges and parking decks are commonly implemented in this process in order to save both time and money. These prefabricated elements are often subjected to moving live loads during construction and repair which, consequently, result in differential movements occurring across the joints connecting the elements of these structures. Potential reductions in joint capacity, joint stiffness, and structural durability are the byproducts …


Air Pressure Energy Storage For Reverse Osmosis: Bench-Scale Proof Of Concept, Ying Sun Aug 2013

Air Pressure Energy Storage For Reverse Osmosis: Bench-Scale Proof Of Concept, Ying Sun

All Theses

Society faces diminishing access to clean drinking water because of increasing global population and the development of modern industries. At the same time, climate change and other environmental problems caused by the increase in fossil fuel consumption the emphasis on reducing dependency on traditional energy resources in the process of potable water production. To address both problems, a small-scale wind powered reverse osmosis (RO) desalination system with a unique energy storage mechanism was envisioned to provide an energy buffer such that fluctuating and intermittent wind can be utilized. Energy is stored in the form of compressed air in a pressure …


An Analysis Of A Missing Design Concept For Sustainable Buildings: Addressing The Safety And Health Of The Construction Worker, Christopher Almond Aug 2013

An Analysis Of A Missing Design Concept For Sustainable Buildings: Addressing The Safety And Health Of The Construction Worker, Christopher Almond

All Theses

Construction work is inherently dangerous. The 2010 U.S. Bureau of Labor Statistics show the construction industry had the most fatal injuries of all industry sectors, 17%. U.S. regulations place the responsibility for construction safety on the construction contractor. However, owners and designers have the potential to affect the safety of the construction workforce. Owners have gotten more involved in promoting the safety and health of construction workers in recent years; however, studies show that the safety and health of the construction workforce is not typically considered by designers.
The Naval Facilities Engineering Command (NAVFAC) - the U.S. Navy's systems command …


Describing Plutonium Contamination Issues In Hanford Soils: Development Of A Thermodynamic Surface Complexation Model, Sarah Herr Aug 2013

Describing Plutonium Contamination Issues In Hanford Soils: Development Of A Thermodynamic Surface Complexation Model, Sarah Herr

All Theses

The development of remediation strategies for long-term site management requires knowledge of an actinide's geochemical behavior. Understanding this behavior can lead to the formation of a subsurface transport model. For example, plutonium mobility in the subsurface environment is significantly influenced by oxidation-reduction and complexation reactions. This work considered the surface-mediated reduction of plutonium, as well as the hydrolysis and carbonate complexation of the actinide.
Evaluating the significance of these reactions required several variable pH batch sorption studies. Experiments incorporated plutonium and neptunium sorption to sediments from the Hanford Nuclear Reservation in Washington State. Two different sediments were examined: coarse-grained and …


Flexural Strength Reliability Of Visually Graded Southern Pine Dimensional Lumber, Mengyu Yang Aug 2013

Flexural Strength Reliability Of Visually Graded Southern Pine Dimensional Lumber, Mengyu Yang

All Theses

The reference design values published in the National Design Specification (NDS) for Wood Construction are derived from full-scale testing of lumber samples performed in the 1980s. This testing program is commonly known as the In-GradeTest Program. Selective annual sample tests of visually graded Southern Pine lumber from 1994 to 2010 revealed an overall decreasing trend in the mechanical properties. Because of this alarming observation, a new round of full-scale In-Grade test of visually graded Southern Pine was initiated in 2010. The new test data indicated significant reductions in certain design values published in the current design code (2005 NDS). …


Application Of Parameter Estimation And Calibration Method For Car-Following Models, Md Rahman Aug 2013

Application Of Parameter Estimation And Calibration Method For Car-Following Models, Md Rahman

All Theses

Both safety and the capacity of the roadway system are highly dependent on the car-following characteristics of drivers. Car-following theory describes the driver behavior of vehicles following other vehicles in a traffic stream. In the last few decades, many car-following models have been developed; however, studies are still needed to improve their accuracy and reliability.
Car-following models are a vital component of traffic simulation tools that attempt to mimic driver behavior in the real world. Microscopic traffic simulators, particularly car-following models, have been extensively used in current traffic engineering studies and safety research. These models are a vital component of …


Data Driven, Performance Based Parking Management In A University Setting, Brian Maleck Aug 2013

Data Driven, Performance Based Parking Management In A University Setting, Brian Maleck

All Theses

With university enrollment increasing, campuses are becoming under increased strain for parking. More students results in more cars on an already stressed parking infrastructure. In many instances, university parking management offices are being asked to accommodate this increase in parking without the construction of new parking infrastructure. In order to accommodate these demands, better parking management is required.
This research develops a framework to evaluate current parking management practices and pinpoint methods to improve upon current practices. The framework is generalized for use by any size and type of university. Clemson University's campus in Clemson, SC was used as a …


Impact Of Channel Conditions On Existing Scour Measuring Instruments, Md Nasimul Hoque Chowdhury Aug 2013

Impact Of Channel Conditions On Existing Scour Measuring Instruments, Md Nasimul Hoque Chowdhury

All Theses

Scour around bridge piers and abutments, is the prominent reason for bridge failures. Bridge failures have substantial effects on economy and human lives. About 60% of the total bridge failures in U.S. can be attributed to scour. In the past, scour has been responsible for several million dollars in bridge repair cost. Given the threat to the bridge infrastructure due to scour, the U.S. Federal Highway Administration has proposed several countermeasures to reduce the impact of bed degradation. One of these countermeasures that is particularly relevant during peak flow periods is the real-time scour monitoring. Scour monitoring involves real-time data …


Corrosion Activity In Precast Concrete Elements And Cementitious Closure Pours, Shabi Abbas Udaipurwala Aug 2013

Corrosion Activity In Precast Concrete Elements And Cementitious Closure Pours, Shabi Abbas Udaipurwala

All Theses

The use of prefabricated elements in the construction of highway bridges has been a common practice in the United States since 1950s. Precast concrete adjacent box beam girder bridges are quite popular given that the precast elements not only have structural capacity to span across the supports, but also form the bridge deck. These bridges have generally performed well during the initial years after construction, but recent failures in Pennsylvania and Indiana have aroused a nationwide alarm to investigate the causes of failure and find solutions to repair these bridges or develop design for new replacement bridges. It was found …


Removal Of N-Nitrosodimethylamine And Trihalomethane Precursors With Powdered Activated Carbon, Wilson Beita Sandi Aug 2013

Removal Of N-Nitrosodimethylamine And Trihalomethane Precursors With Powdered Activated Carbon, Wilson Beita Sandi

All Theses

N-nitrosodimethylamine (NDMA) has been used commercially in several applications, including the production of liquid rocket fuel, and a variety of foods, but gained more relevance when it was discovered as a drinking water disinfection by-product (DBP) in 1989. NDMA is a probable human carcinogen with 10-6 lifetime cancer risk associated with a drinking water concentration of 0.7 ng/L, and is listed as a priority pollutant in the Code of Federal Regulations; no federal maximum contaminant level has been established for drinking water yet. However, the United States Environmental Protection Agency is planning to make a preliminary regulatory determination in 2013 …


Removal Of Arsenic From Simulated Groundwater Using A Pilot-Scale Constructed Wetland Treatment System, Jeffrey Schwindaman Aug 2013

Removal Of Arsenic From Simulated Groundwater Using A Pilot-Scale Constructed Wetland Treatment System, Jeffrey Schwindaman

All Theses

A pilot-scale constructed wetland treatment system (CWTS) was designed and built to produce biogeochemical conditions that promoted targeted processes for removal of arsenic from simulated groundwater. Two series were designed to promote co-precipitation and sorption of arsenic with iron oxyhydroxides under oxidizing conditions, and two series were designed to promote precipitation of arsenic sulfide and co-precipitation of arsenic with iron sulfide under reducing conditions. The two major objectives were to (1) assess arsenic removal performance and (2) determine the fate and distribution of arsenic in each series. Results indicate that arsenic removal performance was greater in series designed to promote …


Evaluation Of Anaerobic Biodegradation Of High Concentrations Of Halogenated Methanes, Priya Rachel Jacob Aug 2013

Evaluation Of Anaerobic Biodegradation Of High Concentrations Of Halogenated Methanes, Priya Rachel Jacob

All Theses

Removal of the chlorinated methanes, carbon tetrachloride (CT), chloroform (CF) and dichloromethane (DCM), and the halogenated methane, trichlorofluoromethane (commonly known as CFC-11 or Freon-11) from contaminated soil and groundwater remains challenging. Releases to the environment resulted from historically poor disposal practices, as well as spills and leaks from underground storage tanks. Among these three compounds, CF is considered the benchmark for evaluating the feasibility of bioremediation, due to its typically high level of toxicity towards most anaerobic prokaryotes. However, inhibitory effects of low concentrations of CFC-11 on anaerobes have been reported as well. Bioremediation is an attractive option for clean-up, …


Probabilistic Back Analysis Of Geotechnical Systems, Lei Wang Aug 2013

Probabilistic Back Analysis Of Geotechnical Systems, Lei Wang

All Theses

This thesis is aimed at applying the probabilistic approaches for back analysis of geotechnical systems. First, a probabilistic back-analysis of a recent slope failure at a site on Freeway No. 3 in northern Taiwan is presented. The Markov Chain Monte Carlo (MCMC) simulation is used to back-calculate the geotechnical strength parameters and the anchor force. These inverse analysis results, which agree closely with the findings of the post-event investigations, are then used to validate the maximum likelihood method, a computationally more efficient back-analysis approach. The improved knowledge of the geotechnical strength parameters and the anchor force gained through the probabilistic …


The Extraction Of Acetic Acid From Thermotoga Neapolitana Fermentation Spent Medium Using Fresh/Recovered Aliquat 336 And Produce Cma, Yifan Du Aug 2013

The Extraction Of Acetic Acid From Thermotoga Neapolitana Fermentation Spent Medium Using Fresh/Recovered Aliquat 336 And Produce Cma, Yifan Du

All Theses

To offer an alternative pathway to produce calcium magnesium acetate (CMA) as an environmental friendly deicer to relieve the pressure on fossil fuels demand, a liquid-liquid extraction process was studied. This process includes using Aliquat 336 (tri-n-octylmethylammonium chloride) diluted in kerosene as an organic extractant to extract acetic acid from Thermotoga neapolitana fermentation spent medium, which contained 34 g/L of acetic acid and 10 g/L of NaCl.
The extraction efficiency of Aliquat 336 was studied under several different extraction conditions. The initial pH of the spent medium was adjusted to a pH range of 2.25 to 5.75 with a 0.5 …


Improvement Of Onsite Wastewater Treatment By Use Of Electrically Conductive Carbon Cloth, Christopher Weber Aug 2013

Improvement Of Onsite Wastewater Treatment By Use Of Electrically Conductive Carbon Cloth, Christopher Weber

All Theses

The purpose of this research is primarily focused on carbon oxidation in domestic septic systems. Small-scale septic waste reactors utilizing electrically conductive carbon cloth were assessed for improving carbon oxidation and therefore the overall efficiency of on-site wastewater treatment systems.
A bioelectrochemical system was developed to enhance carbon oxidation in septic systems using electrically conductive carbon cloth as an anode/cathode bridge to transfer electrons from strictly anoxic septic wastewater to an oxic system outside of the septic reactor. This 'septic snorkel' (so named since the system 'breathes' via the carbon cloth extends into an aerobic zone) was designed to lower …


Modeling Benefits Of Implementing Low Impact Development Practices Within Forecasted Growth Scenarios Of The Reedy River Watershed, Stephen Taylor Aug 2013

Modeling Benefits Of Implementing Low Impact Development Practices Within Forecasted Growth Scenarios Of The Reedy River Watershed, Stephen Taylor

All Theses

For this research, a previously developed comprehensive watershed water quality model for the Reedy River as developed for South Carolina Department of Health and Environmental Control (SCDHEC) and the US Environmental Protection Agency (EPA) as a total maximum daily load (TMDL) assessment tool was used to assess the benefits of using low impact development (LID) designs in future growth of Greenville County, within the Reedy River watershed. The original intent of this model was to provide SCDHEC with a defensible model that could be used to prepare nutrient TMDLs for an area located at Boyd Millpond and the Reedy River …


Noise-Insensitive Prognostic Evaluation Of Historic Masonry Structures, Ashley Haydock May 2013

Noise-Insensitive Prognostic Evaluation Of Historic Masonry Structures, Ashley Haydock

All Theses

In recent years, a significant amount of research has been directed towards the development of prognostic methodologies to forecast the future health state of an engineering system assisting condition based maintenance. These prognostic methods, having furthered the maintenance practices for mechanical systems, have yet to be applied to historic masonry structures, many of which stand in an aged and degraded state. Implementation of prognostic methodologies to historic masonry structures can advance the planning of successful conservation and restoration efforts, ultimately prolonging the life of these heritage structures. This thesis presents a review of prognostic concepts and techniques available in the …


College Level Residential Building Code Education: Current Status And Best Practice, Earl Shealy May 2013

College Level Residential Building Code Education: Current Status And Best Practice, Earl Shealy

All Theses

Community destruction and loss of life due to residential building code (RBC) violations still occur too frequently. Increasing RBC enforcement is often not possible due to lack of funds and resources. Teaching RBC to college-level construction students is another way to encourage greater code compliance and enhanced community resilience. This research assesses the current status of RBC education in accredited construction programs, identifies academic and industry perspectives of RBC education, and constructs 'best practice' RBC teaching strategies.
A mix method, exploratory approach including three distinct phases explains the current phenomenon - RBC education emphasis within university curriculums. My research found …


Influence Of Pcb-Contaminated Water Bodies On The Pcb Content Of Riparian Vegetation Through Foliar Deposition, Timothy Matthew Sattler May 2013

Influence Of Pcb-Contaminated Water Bodies On The Pcb Content Of Riparian Vegetation Through Foliar Deposition, Timothy Matthew Sattler

All Theses

Polychlorinated biphenyls (PCBs) are a class of persistent organic pollutants that are generally considered semi-volatile. Volatilization and transport of PCBs from contaminated water bodies can result in PCB accumulation on terrestrial plant surfaces, acting as an entry point for contaminants into terrestrial food webs. Evergreen plants can serve as biomonitors of this PCB accumulation, as they often retain foliage for several years, allowing for greater concentrations to accumulate and subsequently be measured. Rhododendron maximum plants often grow in the riparian zone adjacent to water bodies in the Appalachian region, such as near Town Creek, Pickens, South Carolina. This research aimed …


The Hydraulic Performance Of Perforated Pipe Under-Drains Surrounded By Loose Aggregate, Patrick Murphy May 2013

The Hydraulic Performance Of Perforated Pipe Under-Drains Surrounded By Loose Aggregate, Patrick Murphy

All Theses

Perforated pipes are commonly used in the construction industry for subsurface drains. These subsurface drains are installed to intercept and convey infiltrated runoff or groundwater. One common application of perforated pipe is to provide an under-drain for an infiltration trench or porous pavement best management practice (BMP). Perforated pipe is installed into a trench on a bed of aggregate ranging from 0 to 28 cm thick and, depending on the design objective, is laid flat or on a slope. However, the actual hydraulic performance of these pipes, i.e. the stage storage relationship, is poorly understood. The resulting flow is quite …