Civil and Environmental Engineering Commons^™

Workability-Integrated Mixture Proportioning Method For Pervious Concrete, Betiglu Eshete Jimma

All Dissertations

Portland cement pervious concrete (PCPC) is increasingly gaining attention as a preferred material in selected pavement applications. This concrete has several unique features, which makes it an environment-friendly construction material. Its porous structure allows precipitation to infiltrate directly into the ground. This reduces accumulation of a large amount of storm water in areas of heavy storms and recharges the ground water system, thus reducing the need for expensive storm water collection and treatment systems. Also, it allows the pollutants on pavement surfaces such as motor oil, etc. to drain into the subsurface be treated by native microbes in the soil, …

Building Envelope Failure Assessment Of Residential Developments Subjected To Hurricane Wind Hazards, James Grayson

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An unfortunate global precedent has been set by hurricane wind hazard events that illustrate the importance of building resilient coastal communities. Although community resilience is heavily dependent upon the socioeconomic response of the community before, during, and after a hazard event, it is also dependent on the vulnerability of the community to a disaster. Therefore, one way that structural engineers can assist communities in becoming more resilient is to investigate and implement methods that mitigate the 'initial shock' experienced by a residential development subjected to a hazard event. The focus of this research was to develop a mechanics-based building envelope …

Predictive Model Development For Adsorption Of Organic Contaminants By Carbon Nanotubes, Onur Apul

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The main objective of the study was to investigate mechanisms and statistical modeling of synthetic organic contaminant (SOC) adsorption by carbon nanotubes (CNTs). First, predictive models were developed for adsorption of low molecular weight aromatic compounds by multi-walled carbon nanotubes (MWCNTs) using experimental data for 59 compounds. Quantitative structure-activity relationship (QSAR) and linear solvation energy relationship (LSER) approaches were employed and developed models were externally validated using an independent dataset obtained from the literature. Up to date, no QSAR model has been reported for predicting adsorption of organics by CNTs. No LSER model is available which comprehensively investigates the adsorption …

Projections Of Future Us Design Wind Speeds Due To Climate Change For Estimating Hurricane Losses, Fangqian Liu

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Hurricane is among the most dangerous and costliest natural hazards that affect the coastal environment of the United States (U.S.) every year. Hurricane activities have been observed to change in many aspects since the last century including the changes in both intensity and annual storm frequency. The extent to which aspect of climate change contributes to the variation in hurricane activities from long-term historical statistics is still not clearly understood at this point. This study examines the impacts of two climate change effects (change in annual storm frequency and sea surface temperature) on future U.S. design wind speeds for the …

The Effects Of Amine Structure, Chloramine Species And Oxidation Strategies On The Formation Of N-Nitrosodimethylamine, Meric Selbes

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To comply with the increasingly stringent disinfection by-product (DBP) regulations in the United States, many water treatment plants have been switching from chlorination to chloramination in the last decade. Although chloramination reduces the formation of regulated DBPs such as trihalomethanes and haloacetic acids, it causes the formation of nitrosamines. Nitrosamines are a class of compounds that are probable human carcinogens, mutagens and teratogens at concentrations as low as 0.2 ng/L. In particular, N-nitrosodimethylamine (NDMA) is the most frequently detected nitrosamine in distribution systems in the United States. Although, nitrosamines are currently not regulated by the USEPA, they have been recently …

Fluid Mud Gravity Currents Through Emergent Aquatic Vegetation, Nazli Yilmaz

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In this theoretical and experimental investigation, the propagation dynamics of the fluid-mud underflows form in pipeline dredge disposal operations in the designated areas are studied. These areas such as wetlands, nearshore waters are typically covered with stiff, cylindrical, emergent aquatic vegetation. The main goals of this study are to propose mathematical formulations for the bottom shear force and drag force of emergent stiff aquatic vegetation acting on the gravity current, and to present novel propagation modeling approaches. To be able to predict these forces, a friction coefficient (for the bottom shear force), and a drag coefficient (for vegetation skin friction …

Influence Of Different Rubber Modified Binder Variables On Performance Properties Of Porous Asphalt Mixtures, Katelyn Love

All Theses

Porous asphalt is a type of pavement in which surface water can permeate down into the subbase below. Open graded friction course (OGFC) is a type of porous asphalt often used as a surface course on top of dense graded pavements on high speed roadways. Due to an increase in waste tires, rubber modified asphalt has become an increasingly popular material around the world, including the US. The rubber modified asphalt is created by utilizing processed rubber particles blended into the mixture. This research investigated the effects of rubber modified binder on the performance of porous asphalt by evaluating the …

Investigation Of Warm Mix Asphalt Overlays And Geosynthetic Pavement Interlayers, William Bolger

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Geosynthetics play an ever increasing role in enhancing pavements. The construction of asphalt overlays with geosynthetic interlayers is a common method to rehabilitate flexible and rigid pavements. Geosynthetic interlayers provide numerous benefits to a pavement system. When utilized properly, geosynthetic interlayers can prevent water from infiltrating a roadway base and can extend the life of a pavement and assist in absorbing stresses. Geoysnthetics lead to an increase in a pavement overlay's performance and also retard reflective cracking. Warm mix asphalt has become more popular as a result of the search for more sustainable construction practices. WMA and its technologies are …

Minimizing Bridge And Pavement Deterioration From Large Trucks: A Policy Analysis For Damage Recovery, Kakan Dey

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Facing an exceptional challenge of maintaining state roadways with ever-shrinking financial resources, this research examined multiple facets of the impact of overweight trucks. The objectives of this research were to investigate the impact of overweight trucks on pavements and bridges, and develop policy recommendations based on technical analysis and the modern political and institutional environment in South Carolina. To achieve the objectives, this research modeled pavement and bridge deterioration, investigated the adequacy of standard practices in state agencies, examined how trucking industry perceives those practices, and developed policy analysis models. Pavement and bridge deterioration analysis revealed that pavement and bridge …

Biomass And Lipid Production Of Chlorella Protothecoides Under Heterotrophic Cultivation On A Mixed Waste Substrate Of Brewer Fermentation And Crude Glycerol, Xiaoyu Feng

All Theses

Biodiesel production using Chlorella protothecoides microalgae species has become an attractive topic due to the intense requirements of renewable energy in past decades. While, the expensive capital cost of the carbon and nitrogen substrates for algae growth is becoming a restrictive problem in this filed. In this study, heterotrophic cultivation of Chlorella protothecoides in the dark was conducted in 500mL shake flasks. Chlorella protothecoides growth in mixed substrate of brewer fermentation and biodiesel crude glycerol by-products containing a relatively high concentration of carbon and nitrogen was discussed and compared with that in microalgae basal medium which was supplied with 30 …

Clemson University Science Master's Program In Sustainable And Resilient Infrastructure: A Program Evaluation, Elizabeth O'Sell

All Theses

The Clemson University Science Master's Program (SMP) in Sustainable and Resilient Infrastructure is a program which aims to link engineering, materials, construction, environment, architecture, business, and public policy to produce graduates with unique holistic perspective and expertise to immediately contribute to the workforce in the area of sustainable and resilient infrastructure. A program evaluation of the SMP has been performed to study the effectiveness of the SMP and identify areas where the goals and vision of the SMP are achieved and areas where improvements can be made. This was completed by analysis of trends within survey responses, review of Master's …

Post-Tensioning To Prevent End-Region Cracks In Pretensioned Concrete Girders, Michael Willis

All Theses

Web-splitting cracking during and immediately after prestress transfer is a common problem in pretensioned concrete beams, often with lasting effects on the durability and performance. By providing an entry point for chlorides and other corrosives, end-region cracks enable degradation of reinforcing steel and further cracking. Current practices offer a variety of methods for controlling end-region cracking. However, methods for preventing--not just controlling or repairing--end-region cracks are necessary to improve prestressed concrete construction. Vertical end-region post-tensioning is a developing method for preventing web-splitting cracks. The purpose of this document is to explore implementation methods of post-tensioning using the turn-of-the nut procedure, …

Preliminary Evaluation Of Kenaf As A Structural Material, Andrew Sheldon

All Theses

Kenaf (Hibiscus cannabinus L.) is an annual fiber plant that is kin to cotton and okra and native to east-central Africa, though it is currently grown in numerous locations around the globe. The plant's apparent high strength and light weight along with its environmental and sustainability advantages makes it a good candidate for use in structural materials. The goal of this study was to design a kenaf product that resembled parallel strand lumber and required minimal processing of the kenaf. The mechanical properties of the two main components of kenaf, the bast fibers and the core, were evaluated using experimental …

Developing A South Carolina Traffic Incident Management Plan Along The I-26 Corridor Between Columbia And Charleston, Laura Rowe

All Theses

Traffic Incident Management (TIM) programs are used in many states across the nation to efficiently clear interstate incidents and alleviate congestion in response to incidents. The overarching goal of this research is to maintain safety of the motoring public and incident responders while reducing congestion, secondary collisions, and traffic delays from incidents that occur on South Carolina highways. To reduce incident clearance times along the I-26 corridor between Columbia and Charleston through the implementation of a Traffic Incident Management (TIM) Program, several objectives for this thesis were established to move toward the goal, including; defining gaps between national TIM best-practices …

Density Functional Theory Study Of The Thermodynamics Of Catalytic Remediation Of Nitrate In Water, Lizzie Bollmann

All Theses

Over 1 billion people worldwide lack access to safe drinking water and 5,000 people die each day due to drinking contaminated water. With the development of new industries, new substances and chemicals are entering the waters every day, and the current water treatment processes are unable to remove them entirely. For example, agriculture is the world's heaviest consumer of water, and nitrates and nitrites from fertilizers are washed away with the water to rivers and streams. These chemicals can cause problems to humans and to the environment. To humans, they can cause methemoglobinemia, also known as 'blue baby syndrome'. To …

Adsorption Of Synthetic Organic Chemicals: A Comparison Of Superfine Powdered Activated Carbon With Powdered Activated Carbon, Semra Bakkaloglu

All Theses

In literature, manufacturer-supplied powdered activated carbon has been ground to produce submicron particles with mean diameter lower than 1µm for use as an adsorbent during water treatment. Superfine powdered activated carbon (SPAC) can be used for removal of natural organic matter as well as synthetic organic chemicals (SOCs) from water. It has been suggested that SPAC has higher adsorption capacity than powdered activated carbon (PAC) due to larger external surface area and mesopore volume. Another advantage of SPAC over PAC is the faster uptake rate for both NOM and SOC during adsorption owing to small particle size. Therefore, understanding SPAC …

Isolated And Ephemeral Wetlands Of Southern Appalachia: Biotic Communities And Environmental Drivers Across Multiple Temporal And Spatial Scales, Joanna Hawley

All Dissertations

Throughout the world, wetlands are known to support a wide variety of taxa as well as high levels of biodiversity and species richness. Although the ecological significance of wetlands is well documented in the scientific literature, efforts to map and assess wetlands on regional or national scales (e.g., National Wetlands Inventory (NWI)) often overlook wetlands which are either very small (< 1 ha) or have ephemeral hydroperiods. While the vast majority of wetland research in the southeastern United States has focused on wetlands distributed across the coastal plain ecoregion, very little information exists on small and/or ephemeral wetlands in areas of southern Appalachia, although there are several notable exceptions. Despite the paucity of small wetland data in this region, the southeastern US is known as a hotspot for both aquatic biodiversity and species endemism. My goal with this project was to examine the biotic communities inhabiting small, ephemeral and geographically-isolated wetlands to identify the major environmental drivers that contribute to observed community patterns and species' distributions. I studied a set of small, mostly-ephemeral, mostly-isolated wetlands (N = 41) in the upper Piedmont and lower Blue Ridge ecoregions of South Carolina from January-June of 2010 and 2011 and focused my efforts on describing the structure, biotic communities and surrounding habitat characteristics of my study wetlands. I observed high levels of species richness and biodiversity in this previously-undocumented wetland system, despite the small size and ephemeral nature of study wetlands. My results indicated that the amphibian and benthic invertebrate communities of small, ephemeral wetlands responded to different environmental drivers (e.g., wetland depth, area, hydroperiod, canopy cover, surrounding land use types) occurring across multiple spatial and temporal scales. Additionally, the amphibian community was significantly influenced by a number of environmental variables occurring at both the within-pond scale and larger spatial scales (250 m, 500 m and 1 km surrounding land cover variables). By contrast, the benthic invertebrate community was significantly influenced primarily by variables occurring at the within-pond scale. This wetland system also served as both breeding and overwintering habitat for a variety of species such as wood frogs (Lithobates sylvatica), spotted salamanders (Ambystoma maculatum), bullfrogs (Lithobates catesbeiana), cricket frogs (Acris crepitans). This study highlights the ecological importance of small, ephemeral aquatic habitats in a region where little research exists regarding such systems; these often-unnoticed ecosystems are likely the result of a combination of historical anthropogenic and natural environmental process. These legacy wetlands (i.e., wetlands that are the unintended result of some human-induced environmental change in either the recent or long-term past) are found ubiquitously across the landscape and are often missed by coarse-filter mapping approaches (e.g., National Wetlands Inventory). I observed many study wetlands to be extremely small in size (< 0.05 ha) and that many wetlands were habitats of circumstance and opportunity rather than of permanence and predictability. The ephemerality of the majority of study wetlands demonstrates the biological significance of small, temporary habitats for many species requiring these habitats for breeding activity. Despite the small size and ephemeral nature of my study wetlands, I found that these wetlands represented a large proportion of amphibian biodiversity in the regional species pool and thus, are an important conservation feature at the local, landscape and regional scales. My study demonstrates that small, semi-isolated, mostly-ephemeral wetlands in southern Appalachia support high levels of biodiversity and are an important asset deserving of further study and conservation recognition.

The Development Of Empirical Models To Evaluate Energy Use And Energy Cost In Wastewater Collection, David Young

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This research introduces a unique data analysis method and develops empirical models to evaluate energy use and energy cost in wastewater collection systems using operational variables. From these models, several Best Management Processes (BMPs) are identified that should benefit utilities and positively impact the operation of existing infrastructure as well as the design of new infrastructure. Further, the conclusions generated herein display high transferability to certain manufacturing processes. Therefore, it is anticipated that these findings will also benefit pumping applications outside of the water sector. Wastewater treatment is often the single largest expense at the local government level. Not surprisingly, …

Numerical Investigation Of One-Dimensional Shallow Water Flow And Sediment Transport Model Using Discontinouous Galerkin Method, Farzam Safarzadeh Maleki

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A one-dimensional shallow water flow and sediment transport model is developed using a discontinuous Galerkin finite element scheme. As a first step, four different time marching schemes as well as three different slope limiters have been investigated to find the optimum modeling combination. The efficiency and accuracy of the time marching schemes and slope limiters are quantitatively examined using CPU runtime and comparison between the simulated results and theoretical/experimental data. It is found that using the second order Adam-Bashforth time marching scheme and Monotonized Central method leads to most efficient and accurate results. As the second part of this research, …

Integrating Algaculture Into Small Wastewater Treatment Plants: Process Flow Options And Life Cycle Impacts, Muriel M. Steele, Annick Anctil, David A. Ladner

Publications

Algaculture has the potential to be a sustainable option for nutrient removal at wastewater treatment plants. The purpose of this study was to compare the environmental impacts of three likely algaculture integration strategies to a conventional nutrient removal strategy. Process modeling was used to determine life cycle inventory data and a comparative life cycle assessment was used to determine environmental impacts. Treatment scenarios included a base case treatment plant without nutrient removal, a plant with conventional nutrient removal, and three other cases with algal unit processes placed at the head of the plant, in a side stream, and at the …

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 …

Application Of Image Processing And Finite Element Analysis In Modeling Chloride Diffusion In Concrete, Arash Razmjoo

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Utilizing numerical simulation models to predict the long-term mechanical and transport behavior of concrete structures is becoming increasingly popular. The majority of these models have been developed using laboratory test data that consider concrete as a homogeneous material with spherical aggregates. These models could not be a represented of real concrete because it has no primitive shaped aggregate besides that the porosity size and distribution varies from point to point. In this study a novel method for more accurate prediction of the chloride diffusion in concrete was developed. A general framework of the quantitative computed tomography (QCT) and finite element …

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.

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 …

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 …

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 …

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 …

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

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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 …

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 …

Predictive Maturity Of Inexact And Uncertain Strongly Coupled Numerical Models, Ismail Farajpour

All Dissertations

The Computer simulations are commonly used to predict the response of complex systems in many branches of engineering and science. These computer simulations involve the theoretical foundation, numerical modeling and supporting experimental data, all of which contain their associated errors. Furthermore, real-world problems are generally complex in nature, in which each phenomenon is described by the respective constituent models representing different physics and/or scales. The interactions between such constituents are typically complex in nature, such that the outputs of a particular constituent may be the inputs for one or more constituents. Thus, the natural question then arises concerning the validity …