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USF Tampa Graduate Theses and Dissertations

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Full-Text Articles in Civil and Environmental Engineering

Environmental Implications Of Pavements: A Life Cycle View, Bin Yu Jan 2013

Environmental Implications Of Pavements: A Life Cycle View, Bin Yu

USF Tampa Graduate Theses and Dissertations

Environmental aspect of pavement, unlike its economic counterpart, is seldom considered in the theoretical study and field practices. As a highly energy and material intensive infrastructure, pavement has great potential to contribute to the environment protection, which, in root, depends on the in-depth understanding of the environmental impacts, holistically and specifically. A life cycle assessment (LCA) model is used to fulfill the goal.

This research firstly carried out extensive literature review of LCA studies on pavement to identify the major research gaps, including: incompleteness of the methodology, controversy of the functional unit, and unawareness of feedstock energy of asphalt, etc. …


Effects Of Solvent Composition And Hydrogen Pressure On The Catalytic Conversion Of 1,2,4,5-Tetrachlorobenzene To Cyclohexane, Margaret Elizabeth Cone Jan 2013

Effects Of Solvent Composition And Hydrogen Pressure On The Catalytic Conversion Of 1,2,4,5-Tetrachlorobenzene To Cyclohexane, Margaret Elizabeth Cone

USF Tampa Graduate Theses and Dissertations

Halogenated hydrophobic organic compounds (HHOCs) such as 1,2,4,5-tetrachlorobenzene (TeCB) present a threat to both human health and the environment. The common occurrence and recalcitrant nature of HHOCs as soil contaminants necessitate an effective soil remediation method. Wee and Cunningham (2008, 2011, 2013) proposed a clean-up technology called Remedial Extraction and Catalytic Hydrodehalogenation (REACH), which pairs solvent extraction of HHOC contaminants from soil with catalytic hydrodehalogenation to destroy contaminants. Wee and Cunningham (2008, 2011, 2013) utilized a palladium (Pd) catalyst to hydrodehalogenate TeCB to benzene. However, benzene is still a toxic contaminant. Prior research has demonstrated that Pd-catalyzed hydrodehalogenation (HDH) can …


Optimized Correlation Of Geophysical And Geotechnical Methods In Sinkhole Investigations: Emphasizing On Spatial Variations In West-Central Florida, Henok Gidey Kiflu Jan 2013

Optimized Correlation Of Geophysical And Geotechnical Methods In Sinkhole Investigations: Emphasizing On Spatial Variations In West-Central Florida, Henok Gidey Kiflu

USF Tampa Graduate Theses and Dissertations

Abstract

Sinkholes and sinkhole-related features in West-Central Florida (WCF) are commonly identified using geotechnical investigations such as standard penetration test (SPT) borings and geophysical methods such as ground penetrating radar (GPR) and electrical resistivity tomography (ERT). Geophysical investigation results can be used to locate drilling and field testing sites while geotechnical investigation can be used to ground truth geophysical results. Both methods can yield complementary information. Geotechnical investigations give important information about the type of soil, groundwater level and presence of low-density soils or voids at the test location, while geophysical investigations like GPR surveys have better spatial coverage and …


Modeling Nitrogen Transformations In A Pilot Scale Marine Integrated Aquaculture System, Brian Mccarthy Jan 2013

Modeling Nitrogen Transformations In A Pilot Scale Marine Integrated Aquaculture System, Brian Mccarthy

USF Tampa Graduate Theses and Dissertations

Integrated aquaculture systems (IAS) are a type of recirculating aquaculture systems (RAS) where the wastewater is treated and returned to the fish tanks. The important difference between the two is that in an IAS, wastes from the aquaculture component are recovered as fertilizer to produce an agricultural product whereas in an RAS, waste organics, nutrients and solids are treated and discharged. A pilot marine IAS at Mote Aquaculture Research Park in Sarasota, FL was studied for this project. Water quality monitoring, measurements of fish health and growth rates of fish and plants were performed over a two-year period to determine …


Evaluation Of A Pilot Land-Based Marine Integrated Aquaculture System, Suzanne Boxman Jan 2013

Evaluation Of A Pilot Land-Based Marine Integrated Aquaculture System, Suzanne Boxman

USF Tampa Graduate Theses and Dissertations

Recirculating aquaculture systems (RAS) produce aquaculture products on land with minimal discharge of waste products and minimal water loss. High costs associated with waste treatment for RAS have triggered the growth of integrated aquaculture systems (IAS) which incorporate macrophytes (aquatic plants) into the treatment train. The objective of this research was to examine a pilot scale inland marine IAS with three different methods for solids treatment: a sand filter followed by a plant bed, only a plant bed, and geotextile bags. Florida Pompano (Trachinotus carolinus) were grown along with Smooth Cordgrass (Spartina alterniflora), Black Needle Rush …


Prediction Of The Performance Of A Flexible Footing On A Stone-Column Modified Subgrade, Justin Callahan Jan 2013

Prediction Of The Performance Of A Flexible Footing On A Stone-Column Modified Subgrade, Justin Callahan

USF Tampa Graduate Theses and Dissertations

When foundations are designed on weak clay layers, it is a common practice to modify the subgrade by installing stone columns. Currently used methods for determining the level of ground modification, represented by the percentage of soil replaced (replacement ratio), assume a rigid foundation. These analytical methods provide the designer with the potential settlement reduction based on the compressibility parameters of the subgrade and the replacement ratio. The deficiencies of these methods are the assumption of rigidity of the foundation and the consideration of the settlement reduction as the only design criterion. Furthermore, they do not consider the effects that …


Effect Of Cement Chemistry And Properties On Activation Energy, Andre J. Bien-Aime Jan 2013

Effect Of Cement Chemistry And Properties On Activation Energy, Andre J. Bien-Aime

USF Tampa Graduate Theses and Dissertations

The objective of this work is to examine the effect of cement chemistry and physical properties on activation energy. Research efforts indicated that time dependent concrete properties such as strength, heat evolution, and thermal cracking are predictable through the concept of activation energy. Equivalent age concept, which uses the activation energy is key to such predictions. Furthermore, research has shown that Portland cement concrete properties are affected by particles size distribution, Blaine fineness, mineralogy and chemical composition. In this study, four Portland cements were used to evaluate different methods of activation energy determination based on strength and heat of hydration …


Socioeconomic Factors' And Water Source Features' Effect On Household Water Supply Choices In Uganda And The Associated Environmental Impacts, Christine M. Prouty Jan 2013

Socioeconomic Factors' And Water Source Features' Effect On Household Water Supply Choices In Uganda And The Associated Environmental Impacts, Christine M. Prouty

USF Tampa Graduate Theses and Dissertations

Over the last twenty years or more, Uganda has benefitted from significant strides in water and sanitation initiated by the United Nations' Millennium Development Goals. While the rapid progress towards development has been vastly beneficial, it is also important that it does not occur at the expense of the environment. The environmental impacts of these water sources must be evaluated and understood. However, to develop a robust understanding of the impact requires inclusion of the community members who use these sources and their perceptions of them. Consequently, the goal of this research is to investigate the interrelationships between socioeconomic factors, …


Community And Household Management Strategies For Water Supply And Treatment In Rural And Peri-Urban Areas In The Developing World, Ryan William Schweitzer Jan 2013

Community And Household Management Strategies For Water Supply And Treatment In Rural And Peri-Urban Areas In The Developing World, Ryan William Schweitzer

USF Tampa Graduate Theses and Dissertations

Eighty percent of the 780 million people worldwide that access water from an unimproved source live in rural areas. In rural areas, water systems are often managed by community based organizations and many of these systems do not provide service at the designed levels. The Sustainability Analysis Tool developed in Chapter 2 can inform decision making, characterize specific needs of rural communities in the management of their water systems, and identify weaknesses in training regimes or support mechanisms. The framework was tested on 61 statistically representative geographically stratified sample communities with rural water systems in the Dominican Republic. The results …


Spatial Transferability Of Activity-Based Travel Forecasting Models, Sujan Sikder Jan 2013

Spatial Transferability Of Activity-Based Travel Forecasting Models, Sujan Sikder

USF Tampa Graduate Theses and Dissertations

Spatial transferability of travel forecasting models, or the ability to transfer models from one geographical region to another, can potentially help in significant cost and time savings for regions that cannot invest in extensive data-collection and model-development procedures. This issue is particularly important in the context of tour-based/activity-based models whose development typically involves significant data inputs, skilled staff, and long production times. However, most literature on model transferability has been in the context of traditionally used trip-based models, particularly for linear regression-based trip generation and logit-based mode choice models, with little evidence on the transferability of activity-based models and that …


Time Scale Of Groundwater Recharge: A Generalized Modeling Technique, Makhan Virdi Jan 2013

Time Scale Of Groundwater Recharge: A Generalized Modeling Technique, Makhan Virdi

USF Tampa Graduate Theses and Dissertations

Estimating the quantity of water that reaches the water table following an infiltration event is vital for modeling and management of water resources. Estimating the time scale of groundwater recharge after a rainfall event is difficult because of the dependence on nonlinear soil characteristics and variability in antecedent conditions. Modeling the flow of water through the variably saturated zone is computationally intensive since it requires simulation of Richards' equation, a nonlinear partial differential equation without a closed-form analytical solution, with parametric relationships that are difficult to approximate. Hence, regional scale coupled (surface water - groundwater) hydrological models make simplistic assumptions …


Assessing Appropriate Technology Handwashing Stations In Mali, West Africa, Colleen Claire Naughton Jan 2013

Assessing Appropriate Technology Handwashing Stations In Mali, West Africa, Colleen Claire Naughton

USF Tampa Graduate Theses and Dissertations

Proper hand hygiene is the most effective and efficient method to prevent over 1.3 million deaths annually from diarrheal disease and Acute Respiratory Infections (ARIs). Hand hygiene is also indispensable in achieving the fourth Millennium Development Goal (MDG) to reduce the childhood mortality rate by 2/3rds between 1990 and 2015. Handwashing has been found in a systematic review of studies to reduce diarrhea by 47%#37; and is, thus, capable of preventing a million deaths (Curtis et. al., 2003). Despite this evidence, hand washing rates remain seriously low in the developing world (Scott et al., 2008).

This study developed and implemented …


Evaluating Cfrp-Masonry Bond Using Thermal Imaging, Joseph Christopher Ross Jan 2013

Evaluating Cfrp-Masonry Bond Using Thermal Imaging, Joseph Christopher Ross

USF Tampa Graduate Theses and Dissertations

This study presents results from non-destructive testing to evaluate the degradation of the CFRP-masonry bond using thermal imaging. The goal of the research was to identify locations where there was evidence of bond deterioration that could subsequently be verified through destructive pull-off testing.

Four full-scale masonry walls were built outdoors at the University of South Florida in 1995 to evaluate the effectiveness of CFRP for repairing settlement damage. Two of the settlement-damaged walls were repaired using single layer, commercially available unidirectional CFRP systems that used Tonen (wall 3) and Henkel (wall 2) epoxies. These two walls were the subject of …


Kelvin Probe Electrode For Contactless Potential Measurement On Concrete-Properties And Applications, Michael Thomas Walsh Jan 2013

Kelvin Probe Electrode For Contactless Potential Measurement On Concrete-Properties And Applications, Michael Thomas Walsh

USF Tampa Graduate Theses and Dissertations

The practical feasibility of using a Kelvin Probe as a novel reference electrode in the measurement of both potential and polarization pulse response of reinforcing steel in concrete is demonstrated. Potential values measured using a KP reflect greater stability and repeatability than can typically be attained with conventional reference electrodes. Duplicate reinforced concrete beam test specimens with well-differentiated centrally corroding rebar segments were analyzed using both the Kelvin Probe (KP) and a conventional Saturated Calomel Electrode (SCE). Potential profile maps were developed using potential values recorded under static conditions with both the SCE and the KP. Nominal polarization resistance was …


Effect Of Localized Corrosion Of Steel On Chloride-Induced Concrete Cover Cracking In Reinforced Concrete Structures, Ezeddin Rafaa Busba Jan 2013

Effect Of Localized Corrosion Of Steel On Chloride-Induced Concrete Cover Cracking In Reinforced Concrete Structures, Ezeddin Rafaa Busba

USF Tampa Graduate Theses and Dissertations

Abstract: Concrete cover cracking due to reinforcement corrosion is widely accepted as a limit-state indicator in defining the end of functional service life for existing reinforced concrete (RC) structures undergoing corrosion. Many of the currently available durability prediction models are incapable of providing realistic estimates of remaining service lives of RC structures beyond the corrosion initiation point. Therefore, the need to incorporate the length of the corrosion propagation stage in a comprehensive durability prediction approach has recently received much research attention. Previous research focus however was mostly limited to the case of uniformly corroding reinforcement with only few studies addressing …


Corrosion Of Post-Tensioning Strands In Ungrouted Ducts - Unstressed Condition, Michael John Hutchison Jan 2013

Corrosion Of Post-Tensioning Strands In Ungrouted Ducts - Unstressed Condition, Michael John Hutchison

USF Tampa Graduate Theses and Dissertations

Recent failures and severe corrosion distress of post-tensioned (PT) bridges in Florida have revealed corrosion of the 7-wire strands in tendons. Post-tensioned duct assemblies are fitted with multiple 7-wire steel strands and ducts are subsequently filled with grout. During construction, the length of time from the moment in which the strands have been inserted into the ducts, until the ducts are grouted, is referred to as the `ungrouted' period. During this phase, the steel strands are vulnerable to corrosion and consequently the length of this period is restricted (typically to 7 days) by construction guidelines. This investigation focuses on determining …


Investigation Of Mercury Use, Release, Deposition, And Exposures In The Tampa Bay Area, Ryan Algernon Michael Jan 2013

Investigation Of Mercury Use, Release, Deposition, And Exposures In The Tampa Bay Area, Ryan Algernon Michael

USF Tampa Graduate Theses and Dissertations

I investigate the links between mercury use, release, deposition, and population exposure in Tampa Bay, with the focus of identifying levers for reducing population mercury exposures. To achieve this, I investigated the trends in mercury use and release by products and processes in the Tampa Bay area using a Material Flow Analysis. Analysis of USEPA National Emissions Inventory data over time (1999 - 2008) identified relevant air source emission categories, and explored and compared state and regional trends in mercury emissions. To understand source contributions to wet deposited mercury in the Tampa Bay area, I analyzed trends in mercury deposition …


Towards Rans Parameterization Of Vertical Mixing By Langmuir Turbulence In Shallow Coastal Shelves, Nityanand Sinha Jan 2013

Towards Rans Parameterization Of Vertical Mixing By Langmuir Turbulence In Shallow Coastal Shelves, Nityanand Sinha

USF Tampa Graduate Theses and Dissertations

Langmuir turbulence in the upper ocean is generated by the interaction between the wind-driven shear current and the Stokes drift velocity induced by surface gravity waves. In homogenous (neutrally stratified) shallow water, the largest scales of Langmuir turbulence are characterized by full-depth Langmuir circulation (LC). LC consists of parallel counter-rotating vortices aligned roughly in the direction of the wind. In shallow coastal shelves, LC has been observed engulfing the entire water column, interacting with the boundary layer and serving as an important mechanism for sediment re-suspension.

In this research, large-eddy simulations (LES) of Langmuir turbulence with full-depth LC in a …


Improving Implementation Of A Regional In-Line Chlorinator In Rural Panama Through Development Of A Regionally Appropriate Field Guide, Benjamin A. Yoakum Jan 2013

Improving Implementation Of A Regional In-Line Chlorinator In Rural Panama Through Development Of A Regionally Appropriate Field Guide, Benjamin A. Yoakum

USF Tampa Graduate Theses and Dissertations

Access to safe drinking water has a direct effect on improving human health and their quality of life. One country still struggling with providing access to safe drinking water to all of its population is Panama. Panama's largest indigenous group, the Ngöbe people, is disproportionately affected by lack of access to safe drinking water. One way Panama's Ministry of Health (MINSA) is attempting to increase access to safe drinking water to the Ngöbe people is by disinfecting the water already captured by rural gravity fed water systems constructed within in the Ngöbe-Bugle reservation. This is accomplished using an in-line chlorinator …


Flexible Urban Drainage Systems In New Land-Use Areas, Jochen Eckart Jun 2012

Flexible Urban Drainage Systems In New Land-Use Areas, Jochen Eckart

USF Tampa Graduate Theses and Dissertations

Urban drainage systems are influenced by several future drivers that affect the performance as well as the costs of the systems. The uncertainties associated with future drivers and their impact creates difficulties in designing urban drainage systems sustainably. A review of the different future drivers for urban drainage systems illustrates that no sufficient future predictions for the long operational life spans of the systems are possible. This dissertation contends that to deal with future uncertainties, flexibility in urban drainage systems is necessary.

At present, profound insights about defining, measuring, and generating flexible urban drainage systems do not exist. This research …


Surface Mass Transfer In Large Eddy Simulation (Les) Of Langmuir Turbulence, Cigdem Akan May 2012

Surface Mass Transfer In Large Eddy Simulation (Les) Of Langmuir Turbulence, Cigdem Akan

USF Tampa Graduate Theses and Dissertations

Over the past century the study of gas exchange rates between the atmosphere and the ocean has received increased attention because of concern about the fate of greenhouse gases such as CO2 released into the atmosphere. Of interest is the oceanic uptake of CO2 in shallow water coastal regions as biological productivity in these regions is on average about three times larger than in the open ocean. It is well-known that in the absence of breaking surface waves, the water side turbulence controls gas transfer of sparingly soluble gases such as CO2 from the air to the …


Modeling Travel Time And Reliability On Urban Arterials For Recurrent Conditions, Prony Bonnaire Fils Apr 2012

Modeling Travel Time And Reliability On Urban Arterials For Recurrent Conditions, Prony Bonnaire Fils

USF Tampa Graduate Theses and Dissertations

Abstract

Travel time reliability is defined as the consistency or dependability in travel times during a specified period of time under stated conditions, and it can be used for evaluating the performance of traffic networks based on LOS (Level of Service) of the HCM (Highway Capacity Manual). Travel time reliability is also one of the most understood measures for road users to perceive the current traffic conditions, and help them make smart decisions on route choices, and hence avoid unnecessary delays (Liu & Ma, 2009). Therefore, travel time reliability on urban arterials has become a major concern for daily commuters, …


Understanding Operating Speed Variation Of Multilane Highways With New Access Density Definition And Simulation Outputs, Bing Huang Apr 2012

Understanding Operating Speed Variation Of Multilane Highways With New Access Density Definition And Simulation Outputs, Bing Huang

USF Tampa Graduate Theses and Dissertations

Traffic speed is generally considered a core issue in roadway safety. Previous studies show that faster travel is not necessarily associated with an increased risk of being involved in a crash. When vehicles travel at the same speed in the same direction (even high speeds, as on interstates), they are not passing one another and cannot collide as long as they maintain the same speed. Conversely, the frequency of crashes increases when vehicles are traveling at different rates of speed. There is no doubt that the greater speed variation is, the greater the number of interactions among vehicles is, resulting …


Development And Application Of An F/M Based Anaerobic Digestion Model And The Rt-Ribosyn Molecular Biology Method, Matthew Raymond Cutter Mar 2012

Development And Application Of An F/M Based Anaerobic Digestion Model And The Rt-Ribosyn Molecular Biology Method, Matthew Raymond Cutter

USF Tampa Graduate Theses and Dissertations

A simple anaerobic digestion model has been developed for a continuously-stirred tank reactor (CSTR), which links the specific biogas production rate to the food/microorganism ratio (F/M). The model treats the various microbial populations involved in the sequential biological processes involved in anaerobic digestion as a composite and links the entire biomass specific growth rate directly to the specific biogas production rate. The model was calibrated by determining the specific gas production rate for a range of F/M values using a municipal wastewater seed sludge. The model predictions for steady-state biogas production rates were compared to observed biogas production and volatile …


Rainwater Harvesting Storage Methods And Self Supply In Uganda, Jonathan Peter Blanchard Mar 2012

Rainwater Harvesting Storage Methods And Self Supply In Uganda, Jonathan Peter Blanchard

USF Tampa Graduate Theses and Dissertations

Self supply is an emerging approach to water supply which focuses on fostering household investment in incremental improvements to their water sources. When successful, it can lower costs and increase sustainability by offering users a larger share

of ownership in their own supply, and harnessing the already existing strengths of a community rather than trying to impose an external perspective. In addition to well upgrading and source protection, one of the key self supply areas is rainwater harvesting.

Uganda has a diverse selection of rainwater storage options, but many of them are scattered and disparate.

The objective of this study …


Willingness-To-Pay For Maintenance And Improvements To Existing Sanitation Infrastructure: Assessing Community-Led Total Sanitation In Mopti, Mali, Justin Vern Meeks Mar 2012

Willingness-To-Pay For Maintenance And Improvements To Existing Sanitation Infrastructure: Assessing Community-Led Total Sanitation In Mopti, Mali, Justin Vern Meeks

USF Tampa Graduate Theses and Dissertations

In recent years, much focus has been put on the sustainability of water and sanitation development projects. Experts in this field have found that many of the projects of the past have failed to achieve sustainability because of a lack of demand for water and sanitation interventions at a grassroots level. For years projects looked to create this demand through various subsidy schemes, with the "software" of behavior change and education taking a backseat to the "hardware" of infrastructure provision. Community-Led Total Sanitation (CLTS) is a fairly new way of looking at the issues of increasing basic sanitation coverage, promoting …


Development Of An Integrated Process Model For Algae Growth In A Photobioreactor, Mehregan Jalalizadeh Mar 2012

Development Of An Integrated Process Model For Algae Growth In A Photobioreactor, Mehregan Jalalizadeh

USF Tampa Graduate Theses and Dissertations

While understanding the kinetics of algae growth plays an important role in improving algae cultivation technology, none of the existing kinetic models are able to describe algae growth when more than three growth limiting factors are involved. A model was developed in this study to describe algae growth in a photobioreactor. Two expressions were proposed based on the Monod model to relate the specific growth rate of algae to the concentration of nitrogen, phosphorus, inorganic carbon and light intensity in the culture media. Algal biomass concentration as a function of time was calculated by solving mass and energy balances around …


Technical And Economic Assessment Of Adobe As The Primary Building Material On The Water Yield Of A Single Basin Solar Still, Nathan Daniel Manser Mar 2012

Technical And Economic Assessment Of Adobe As The Primary Building Material On The Water Yield Of A Single Basin Solar Still, Nathan Daniel Manser

USF Tampa Graduate Theses and Dissertations

It is estimated that only one percent of global freshwater is available to humans, with nearly three billion people living in water scarce conditions. Populations living in impoverished settings are particularly vulnerable to water related illnesses, with approximately 2.2 million people dying each year from to waterborne illnesses. This research uses modeling and field studies to assess the quantity, quality, and economics of distillate produced for drinking water from a brackish water source using two single-sloped, single-basin distillation reactors. The reactors were constructed from adobe and concrete in an arid rural community in San Luis Potosí, Mexico and tested from …


Water Quality Monitoring In A Pilot Marine Integrated Aquaculture System, Alex W. Kruglick Mar 2012

Water Quality Monitoring In A Pilot Marine Integrated Aquaculture System, Alex W. Kruglick

USF Tampa Graduate Theses and Dissertations

Land based aquaculture systems are growing in popularity, and there is a drive to improve the efficiency of their energy and water systems for both economic and environmental benefit. Recirculating Aquaculture Systems (RAS) generally refer to systems that recycle their wastewater streams to be more or less a zero discharge facility. A more sustainable approach is emerging in the form of Integrated Aquaculture Systems (IAS) where maximum utility is realized from the various components so that fresh water use is reduced, water quality is improved, energy use is reduced, and new markets are created or fulfilled. Under a grant from …


Field And Laboratory Comparison Of The Hydraulic Performance Of Two Ceramic Pot Water Filters, Duncan Peabody Jan 2012

Field And Laboratory Comparison Of The Hydraulic Performance Of Two Ceramic Pot Water Filters, Duncan Peabody

USF Tampa Graduate Theses and Dissertations

Currently 884 million people worldwide are living without access to an improved source of drinking water (WHO/UNICEF, 2011). Piped-water on premises is the ultimate goal of World Health Organization (WHO) due to the ability to treat all of the water and distribute it safely in pressurized pipes. However, Household Water Treatment and Safe Storage (HWTS) is an option for improving the quality of drinking water where that infrastructure is not yet developed, especially where there is a risk of recontamination between point of collection and point of use (Clasen, 2006).

This study analyzed one such HWTS, the ceramic pot water …