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Title: Exploration of Monostrand Use in Segmental Box Girder Bridges.
Creator: Spear, Herbert Houston, Rambo-Roddenberry, Michelle, Spainhour, Lisa, Tawfiq, Kamal, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: For the past several decades the segmental box girder bridge has proven itself to be one of the more efficient bridge types. Using reusable form work, segments are match-cast, ensuring a more perfect connection during the construction phase. These benefits in conjunction with the fact that the costs of startup and form work are absorbed into the total cost of each segment mean that the longer the final bridge is, the less the cost is per segment, making the segmental box girder bridge one of...
Show moreFor the past several decades the segmental box girder bridge has proven itself to be one of the more efficient bridge types. Using reusable form work, segments are match-cast, ensuring a more perfect connection during the construction phase. These benefits in conjunction with the fact that the costs of startup and form work are absorbed into the total cost of each segment mean that the longer the final bridge is, the less the cost is per segment, making the segmental box girder bridge one of the most popular long bridge types constructed in the U.S. To minimize cost, it is important to design each segment for efficiency in terms of quantity of longitudinal and transverse post-tensioning and reinforcing steel. The inclusion of post-tensioning technology results in an overall compressive state in the longitudinal and transverse directions of the segments, improving structure strength and service life. However, despite the benefits inherent in using post-tensioning technology, the webs still contain standard deformed reinforcement. The goal of this research is to fit a greased and sheathed monostrand within a segment in a way that both webs and bottom flange would be placed in a state of compression, thereby reducing the demand for standard web reinforcement and, hopefully, segment cost. The research objectives include analyzing principal stresses in the webs of the segment, modifying the segment so as to restrain the monostrand within the webs, designing any additional reinforcement that may be necessary, and finally comparing the estimated construction cost of the new design with that of a pre-existing structure. The results from this research have shown that it is indeed possible to place a greased and sheathed monostrand within the webs of a segment with beneficial results and that the demand for standard deformed reinforcement will thus be reduced.
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Date Issued: 2010
Identifier: FSU_migr_etd-0375
Format: Thesis

Title: Improving Design of the BNR Process in Wastewater Treatment Plants from an Operations Perspective.
Creator: Zickefoose, Brie, Leszczynska, Danuta, Hilton, Amy Chan, Dzurik, Andrew, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: Sole nutrient removal from wastewater discharges has become an increasing challenge, as regulatory authorities tighten discharge standards to avoid eutrophication problems in receiving waters. Engineers have become aware that there is a need for new engineering design of standard wastewater treatment plants that should include removal of nutrients (nitrogen and phosphorus) in an efficient and cost effective manner. This need led to the development of biological nutrient removal (BNR) process,...
Show moreSole nutrient removal from wastewater discharges has become an increasing challenge, as regulatory authorities tighten discharge standards to avoid eutrophication problems in receiving waters. Engineers have become aware that there is a need for new engineering design of standard wastewater treatment plants that should include removal of nutrients (nitrogen and phosphorus) in an efficient and cost effective manner. This need led to the development of biological nutrient removal (BNR) process, which is a distinctive modification of the basic activated sludge process. The BNR process is controlled in bioreactor with separate zones that create different biochemical environments, which allow the system to remove a high degree of nitrogen and phosphorus from the wastewater. There are many uncertainties and uncontrollable factors in the BNR process, therefore achieving high reliability depends heavily on knowledgeable operators and engineers. Operators and start-up engineers can help design engineers become more knowledgeable about uniqueness in design by passing on key information that becomes available during operations. This information was collected and used to improve design's layout of BNR bioreactor to accommodate all observed operational deficiencies. The deficiencies found during operations were related to start-up conditions, climate, process related issues and equipment spacing. Start-up conditions, climate and equipment need to be considered more closely during design. Engineers can learn from the process related deficiencies found during operations to improve the process design.
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Date Issued: 2004
Identifier: FSU_migr_etd-0507
Format: Thesis

Title: Evaluation of Engineering Properties of Hot Mix Asphalt Concrete for the Mechanistic-Empirical Pavement Design.
Creator: Xiao, Yuan, Ping, Wei-Chou V., Niu, Xufeng, Abichou, Tarek, Sobanjo, John, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: Hot Mix Asphalt (HMA) is a viscoelastic material and has been broadly used in pavement structures. It is important to understand the mechanism of complex behaviors of HMA mixtures in field for improving pavement mechanical performance. Aggregate gradation and asphalt binder are two key factors that influence the engineering properties of HMA. The asphalt binder plays a significant role in elastic properties of HMA and it is the essential component that determines HMA's viscous behavior. Many...
Show moreHot Mix Asphalt (HMA) is a viscoelastic material and has been broadly used in pavement structures. It is important to understand the mechanism of complex behaviors of HMA mixtures in field for improving pavement mechanical performance. Aggregate gradation and asphalt binder are two key factors that influence the engineering properties of HMA. The asphalt binder plays a significant role in elastic properties of HMA and it is the essential component that determines HMA's viscous behavior. Many research works suggest that Styrene-Butadiene-Styrene (SBS) polymer is a promising modifier to improve the asphalt binder, and hence to benefit the HMA viscoelastic properties. The specific beneficial characteristics and appropriate polymer concentration need to be identified. In addition, aggregate gradation requirements have been defined in Superpave mix design criteria. However, a potentially sound coarse mixture with the gradation curve passing below the coarse size limit may be disqualified from being used. There is a need to evaluate the Superpave gradation requirements by studying mixtures purposely designed exceeding the control limits. Moreover, the mechanical parameters adopted by AASHTO to characterize HMA properties are shifting from indirect diametral tensile (IDT) test to dynamic modulus test (DMT), because the DMT has the ability to simulate real traffic conditions and to record more viscoelastic information of HMA. Thus, the DMT and the IDT test for implementing the AASHTO Mechanistic-Empirical Design Guide (M-E PDG) are needed to be discussed. The primary objective of this research study was to evaluate the fracture mechanics properties of HMA concrete and to study the correlation between the DMT and the IDT test for Superpave mixtures. An experimental program was performed on asphalt mixtures with various types of materials. The laboratory testing program was developed by applying a viscoelastic fracture mechanics-based framework that appeared to be capable of describing the whole mechanical properties of HMA according to past research studies. The goals for these experiments are to evaluate the effect of aggregate type, the effect of gradation adjustment to control mix designs, and the effect of SBS polymer on fracture mechanics properties of HMA mixtures. Two standard coarse mixes were selected as control levels for fracture mechanics tests: one granite mixture and one limestone mixture. Each control mix design was modified to two different gradation levels with the control asphalt binder (PG 67-22) and three SBS polymer content levels (3.0%, 4.5%, and 6.0%) with the original aggregate gradation. The experimental program for dynamic complex modulus test involved 20 Superpave asphalt concrete mixtures commonly used in Florida with a range of aggregates and mix designs. Data evaluation of the test results indicated the increase of nominal maximum size aggregate amount by 5% to 15% to the standard coarse mix designs had negligible effect on HMA fracture mechanics properties. The SBS polymer-modified asphalt binder improved the fracture mechanics behavior of asphalt mixtures comprehensively. The limestone materials hold advantages over granite materials in improving the performance of thermal cracking at low service temperatures and the rutting resistance at high service temperatures. The master curve construction and linear regression analysis indicated that the total resilient modulus increased with an increase in dynamic modulus at a specific loading frequency. The resilient modulus values were comparable with the dynamic modulus values at the loading frequency of 4 Hz. A correlation relationship was developed for predicting the dynamic modulus from existing resilient modulus values of the asphalt concrete mixture in implementing the mechanistic-empirical pavement design.
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Date Issued: 2009
Identifier: FSU_migr_etd-0411
Format: Thesis

Title: Analysis and Predictions of Extreme Coastal Water Levels.
Creator: Xu, Sudong, Huang, Wenrui, Niu, Xufeng, Nnaji, Soronnadi, Abichou, Tarek, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: Understanding the characteristics of probability distribution of extreme water levels is important for coastal flood mitigation and engineering design. In this study, frequency analysis has been conducted to investigate probability distributions along the coast of the U.S. by using three-parameter General Extreme Value (GEV) method. The GEV model combines three types of probability distributions (Type I for Gumbel distribution, Type II for Fretchet, or Type III for Weibull) into one...
Show moreUnderstanding the characteristics of probability distribution of extreme water levels is important for coastal flood mitigation and engineering design. In this study, frequency analysis has been conducted to investigate probability distributions along the coast of the U.S. by using three-parameter General Extreme Value (GEV) method. The GEV model combines three types of probability distributions (Type I for Gumbel distribution, Type II for Fretchet, or Type III for Weibull) into one expression. Types of distributions can be clarified by one of the three parameters of the GEV model for the corresponding studied stations. In this study, the whole U.S. coast was divided into four study areas: Pacific Coast, Northeast Atlantic Coast, Southeast Atlantic Coast and Gulf of Mexico Coast. Nine National Oceanic and Atmospheric Administration (NOAA) stations with a long history of data (more than 70 years) in the four study areas were chosen in this study. Parameters of the GEV model were estimated by using the annual maximum water level of studied stations based on the Maximum Likelihood Estimation (MLE) method. T-test was applied in this study to tell if the parameter, , was greater than, less than or equal to 0, which was used to tell the type of the GEV model. Results show that different coastal areas have different probability distribution characteristics. The characteristics of probability distribution in Pacific Coast and Northeast Atlantic Coast are similar with extreme value I and III model. The Southeast Atlantic Coast and Gulf of Mexico Coast were found to have similar probability distribution characteristics. The probability distributions were found to be extreme value I and II model, which are different from those of the Pacific Coast and Northeast Atlantic Coast. The performance of the GEV model was also studied in the four coastal areas. GEV model works well in the five studied stations of both the Pacific Coast and the Northeast Atlantic Coast but does not work well in the Southeast Atlantic Coast and the Gulf of Mexico Coast. Adequate predictions of extreme annual maximum coastal water levels (such as 100-year flood elevation) are also very important for flood hazard mitigation in coastal areas of Florida, USA. In this study, a frequency analysis method has been developed to provide more accurate predictions of 1% annual maximum water levels for the Florida coast waters. Using 82 and 94 years of water level data at Pensacola and Fernandina, performances of traditional frequency analysis methods, including advanced method of Generalized Extreme Value distribution method, have been evaluated. Comparison with observations of annual maximum water levels with 83 and 95 return years indicate that traditional methods are unable to provide satisfactory predictions of 1% annual maximum water levels to account for hurricane-induced extreme water levels. Based on the characteristics of annual maximum water level distribution Pensacola and Fernandina stations, a new probability distribution method has been developed in this study. Comparison with observations indicates that the method presented in this study significantly improves the accuracy of predictions of 1% annual maximum water levels. For Fernandina station, predictions of extreme water level match well with the general trend of observations. With a correlation coefficient of 0.98, the error for the maximum observed extreme water level of 3.11 m (NGVD datum) with 95 return years is 0.92 %. For Pensacola station, the prediction error for the maximum observed extreme water level with a return period of 83 years is 5.5 %, with a correlation value of 0.98. In frequency analysis of 100 year coastal flood (FEMA 2005), annual extreme high water levels are often used. However, in many coastal areas, long history data of water levels are unavailable. In addition, some water level records may be missed due to the damage of measurement instruments during hurricanes. In this study, a method has been developed to employ artificial neural network and harmonic analysis for predicting extreme coastal water levels during hurricanes. The combined water levels were de-composed into tidal signals and storm surge. Tidal signal can be derived by harmonic analysis, while storm surge can be predicted by neural network modeling based on the observed wind speeds and atmospheric pressure. The neural network model employs three-layer feed-forward backgropagation structure with advanced scaled conjugate training algorithm. The method presented in this study has been successfully tested in Panama City Beach and Apalachicola located in Florida coast for Hurricane Dennis and Hurricane Ivan. In both stations, model predicted peak elevations match well with observations in both hurricane events. The decomposed storm surge hydrograph also make it possible for analysis potential extreme water levels if storm surge occurs during spring high tide.
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Date Issued: 2007
Identifier: FSU_migr_etd-0416
Format: Thesis

Title: Traffic Capacity and Speed Analyses of Freeway Work Zones Based on Computer Simulation.
Creator: Zhu, Kangyuan, Ping, W. Virgil, Mussa, Renatus Nyakiamo, Tung, Leonard J., Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: Traffic capacity, queue discharge rates and vehicle speeds at work zones were equally essential in assessment of work zone performance and traffic operation. This study was conducted to analyze the traffic flow characteristics in freeway work zones based on the traffic data collected from CORSIM simulation. A total seven related factors were input into CORSIM software and 129,600 times of CORSIM simulation were run in the designed experiments. In the capacity and queue discharge rate analyses...
Show moreTraffic capacity, queue discharge rates and vehicle speeds at work zones were equally essential in assessment of work zone performance and traffic operation. This study was conducted to analyze the traffic flow characteristics in freeway work zones based on the traffic data collected from CORSIM simulation. A total seven related factors were input into CORSIM software and 129,600 times of CORSIM simulation were run in the designed experiments. In the capacity and queue discharge rate analyses, it was found that capacity could not be obtained definitely on the onset of congested traffic conditions at work zones although the probability to reach the maximum flow rate on the onset of congested traffic conditions was the highest. With analysis of variance, it was found that almost all the levels in each selected factor were statistical significant with respect to the capacity and mean queue discharge rate. The additive regression models of capacity and mean queue discharge rate with the related factors were obtained. The capacity regression models had R-Square 0.903 and 0.726 respectively with or without considering the interaction effects of two factors. However, the models for mean queue discharge rate had R-Square 0.944 and 0.762 respectively with or without considering the interaction effects of two factors. The results showed that consideration of interaction effects of factors would improve the fitness of models greatly. In addition, mean queue discharge rate was more stable to estimate than the capacity. Number of simulation runs required for capacity analyses at work zones was also studied. It was found that 5 times of simulation runs were adequate for capacity analyses with 95% confident level within 5% estimation errors. In speed analyses, under uncongested traffic conditions, the speeds along freeway work zones were controlled mainly by the FFS (or Speed Limit) although there were some minor fluctuations in the traffic flow. However, under congested traffic conditions the speed characteristics were much more complex and the standard deviation of vehicle speeds were much larger. The speed patterns under congested traffic conditions could be divided into seven sections each with different traffic flow characteristics. Since the large standard deviations of the point speeds, only space-mean speed in three sections out of the seven sections was analyzed. Additive regression models of space-mean speed with related factors were developed under both congested and uncongested traffic conditions. The results showed space-mean speed models under uncongested traffic conditions had R-Square 0.902 and 0.870 respectively with or without considering the interaction effects of two factors. However, under congested traffic conditions, space-mean speed models had R-Square 0.801 and 0.742 respectively with or without considering the interaction effects of two factors. It indicated that it was more difficult to estimate speeds under congested traffic flow. In addition, simulation runs were analyzed for space-mean speed estimation at freeway work zones. The results showed 5 times of simulation runs were adequate for speed analyses with 95% confident level within 10% estimation errors under uncongested traffic conditions. However, under congested traffic conditions, 7 or more times of simulation runs were preferred.
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Date Issued: 2004
Identifier: FSU_migr_etd-0516
Format: Thesis

Title: Bio-Reactive Landfill Covers: An Inexpensive Approach to Mitigate Methane Emissions.
Creator: Escoriaza, Sharon Czarina, Abichou, Tarek, Chanton, Jeff, Chan-Hilton, Amy, Powelson, Dave, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: Methane is one of two primary gases produced from the decomposition of landfill waste. Studies have been directed to collection and mitigation of methane gas. In small landfills, collection is not an economically feasible solution. Bio-cover placement is an inexpensive approach to mitigating methane emissions. The enhancing of oxidation processes by placement of bio-covers will reduce emissions even while gas extraction is employed and improve aesthetic quality of solid waste facilities. The...
Show moreMethane is one of two primary gases produced from the decomposition of landfill waste. Studies have been directed to collection and mitigation of methane gas. In small landfills, collection is not an economically feasible solution. Bio-cover placement is an inexpensive approach to mitigating methane emissions. The enhancing of oxidation processes by placement of bio-covers will reduce emissions even while gas extraction is employed and improve aesthetic quality of solid waste facilities. The overall objective of the research is to mitigate methane emissions from landfills. To reach this objective, a test site was selected to evaluate the effects of compost placement over a closed landfill. The static chamber technique was used to estimate methane emissions and the stable isotope tracing method was used to determine oxidation rates. Hot spots were identified in the grid area and emissions at these spots were analyzed more in detail. Results obtained during the first year of the study are presented in this thesis. In these investigative efforts, it was noted that moisture content plays a significant role in controlling emissions and oxidation. At high water contents, low flux emissions were measured observed and at low water contents, emissions were higher. Oxidation rates varied in much the same way. High water contents corresponded with low oxidation rates and vise versa. Further study on the effects of moisture content and other variables on flux emission and oxidation is warranted.
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Date Issued: 2005
Identifier: FSU_migr_etd-0520
Format: Thesis

Title: Fatigue Evaluation of Structural Composite Lumber (SCL) T-Beam Bridge Girders.
Creator: Enam, Muhammad Badre, Mtenga, Primus V., Tawfiq, Kamal S., Spainhour, Lisa, Kalu, Peter N., Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: Recent innovation in the engineered wood industry has produced Structural Composite Lumber (SCL) that tends to achieve maximum strength, stiffness and efficient use of wood. Product variations of SCL such as Laminated Veneer Lumber (LVL) and Parallel Strand Lumber (PSL), are currently being used in the transportation sector to produce bridge girders, decks etc. for rural and other low traffic volume roads. Although, the elastic and shear properties of SCL materials are clearly understood, no...
Show moreRecent innovation in the engineered wood industry has produced Structural Composite Lumber (SCL) that tends to achieve maximum strength, stiffness and efficient use of wood. Product variations of SCL such as Laminated Veneer Lumber (LVL) and Parallel Strand Lumber (PSL), are currently being used in the transportation sector to produce bridge girders, decks etc. for rural and other low traffic volume roads. Although, the elastic and shear properties of SCL materials are clearly understood, no attempt has been made to estimate fatigue performance of these bridge girders. With their increasing use, they are repeatedly being subjected to numerous cycles of wheel load that raises concern about their behavior under fatigue. The current research tested 12 newly procured and 2 old and weathered pre-built SCL T-beam bridge girders for flexural fatigue under a stress controlled test setup. The girders were of 20 ft span and having variation in their constituent material types and applied preservatives. Loading was applied according to the AASHTO LRFD specifications for bridge design. The number of load application cycles was consistent with expected traffic volume for a sixty year time span. In a regular bridge structure comprised of pre-built SCL T-beam girders, transverse post-tension is applied to adjacent girders to form a stress laminated deck. This effect had been simulated on the girders and the effect of fatigue loading on the loss of post-tension force was observed. Results from the study indicated that the SCL Tbeam bridge girders were capable of withstanding the repetitive loads coming from the heavy truck traffic. Most of the beams did not suffer any physical damage. A few of them had severe de-lamination at the SCL-epoxy interface. The girders without any damage due to fatigue were loaded statically up to failure. This result was compared to the ultimate flexural strength of fresh beams of similar material type, to investigate their residual strengths after fatigue loading. Some weathered girders were also fatigued under the same experimental setup for comparison purposes. This provided a comparison of the fatigue performance of fresh and weathered SCL T-beam bridge girders. Comparably high strength fatigue loading was applied to two additional girders. The fatigue lives for these girders were less and compared well with those of clear wood at the same stress level. A rudimentary fatigue curve was proposed based on the data. A finite element model was developed, using layered shell elements, to simulate the structural behavior of these girders. Subsequent analyses of this model produced results that were highly representative of the data obtained in experimental testing of SCL T-beam girders.
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Date Issued: 2008
Identifier: FSU_migr_etd-0565
Format: Thesis

Title: Environmental Impact Assessment of Transportation Projects: An Analysis Using an Integrated GIS, Remote Sensing, and Spatial Modeling Approach.
Creator: El-Gafy, Mohamed Anwar, AbdelRazig, Yassir A., Zahn, Douglas A., Sobanjo, John O., Mussa, Renatus N., Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: Transportation projects will have impact on the environment. The general environmental pollution and damage caused by roads is closely associated with the level of economic activity. Although Environmental Impact Assessments (EIAs) are dependent on geo-spatial information in order to make an assessment, there are no rules per se how to conduct an environmental assessment. Also, the particular objective of each assessment is dictated case-by-case, based on what information and analyses are...
Show moreTransportation projects will have impact on the environment. The general environmental pollution and damage caused by roads is closely associated with the level of economic activity. Although Environmental Impact Assessments (EIAs) are dependent on geo-spatial information in order to make an assessment, there are no rules per se how to conduct an environmental assessment. Also, the particular objective of each assessment is dictated case-by-case, based on what information and analyses are required. The conventional way of Environmental Impact Assessment (EIA) study is a time consuming process because it has large number of dependent and independent variables which have to be taken into account, which also have different consequences. With the emergence of satellite remote sensing technology and Geographic Information Systems (GIS), this research presents a new framework for the analysis phase of the Environmental Impact Assessment (EIA) for transportation projects based on the integration between remote sensing technology, geographic information systems, and spatial modeling. By integrating the merits of the map overlay method and the matrix method, the framework analyzes comprehensively the environmental vulnerability around the road and its impact on the environment. This framework is expected to:1) improve the quality of the decision making process, 2) be applied both to urban and inter-urban projects, regardless of transport mode, and 3) present the data and make the appropriate analysis to support the decision of the decision-makers and allow them to present these data to the public hearings in a simple manner. Case studies, transportation projects in the State of Florida, were analyzed to illustrate the use of the decision support framework and demonstrate its capabilities. This cohesive and integrated system will facilitate rational decisions through costeffective coordination of environmental information and data management that can be tailored to specific projects. The framework would facilitate collecting, organizing, analyzing, archiving, and coordinating the information and data necessary to support technical and policy transportation decisions.
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Date Issued: 2005
Identifier: FSU_migr_etd-0580
Format: Thesis

Title: Evaluation of Dynamic Load Allowance Factors for Reinforced Concrete Highway Bridges.
Creator: Earle, Sharnie Fiona, Wekezer, Jerry, Rambo-Roddenberry, Michelle, Mtenga, Primus, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: The evaluation of existing structures is critical for the efficient management of transportation facilities, especially bridges. According to the Florida Department of Transportation Plan, Safety, and System Management, which include bridge repairs and replacements, a cost of about 30% of all state and federal revenues will be needed in order to get the nation's bridge integrity to a sufficient level [4]. ASCE estimates $930 billion dollars will be needed within 5 years in order to improve...
Show moreThe evaluation of existing structures is critical for the efficient management of transportation facilities, especially bridges. According to the Florida Department of Transportation Plan, Safety, and System Management, which include bridge repairs and replacements, a cost of about 30% of all state and federal revenues will be needed in order to get the nation's bridge integrity to a sufficient level [4]. ASCE estimates $930 billion dollars will be needed within 5 years in order to improve all roads and bridges. This project responds to the growing need to rehabilitate our nation's bridges by focusing on vehicle-bridge interaction. Frequently, bridges are evaluated using traditional stability methods and simplified static analysis methods. The main objective of this research was the analysis of an already verified and validated bridge model in order to improve on the dynamic nature of vehicle-bridge interaction. Special attention was made to the improvement of the elastomeric bearing pads in the existing model. The main reason focus was placed on this part of the bridge was due to the fact that these pads are ideal for bridge design because they are economical, effective, and require no maintenance. They deflect in shear to accommodate expansion, contraction, and end rotation of the bridge. There is no need for lubrication, cleaning, nor do they have the opportunity to seize. In order to analyze the improvements of the older bearing pads, an in-lab compression test was created using the same finite element software that was used to create the bridge model. Several compression tests were performed using different material properties in order to determine which set of material characteristics would yield the best results for the improvement of these pads. Once these parameters were determined, they were then verified and validated by a program known as the Roadside Safety Validation and Verification Program, RSVVP. This program is an essential part when developing a model if the model is to be accepted and used to support decision making. The parameters that yield the closest results to the actual field test were then implemented onto the new bridge model. This ensured that the new bridge model was in fact a better representation of what happens in the field. A final calculation of the dynamic load allowance, DLA verified that the vehicle-bridge interaction was successful due to the DLA factor decreasing when compared to the previous calculated DLA factors from an existing vehicle-bridge interaction research.
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Date Issued: 2010
Identifier: FSU_migr_etd-0608
Format: Thesis

Title: Assessing the Financial Feasibility of Implementing Wireless Technologies for Construction Management.
Creator: Singletary, Matthew Ryan, AbdelRazig, Yassir, Ping, Wei-Chou V., Sobanjo, John, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: The construction industry has been one of the slowest to assimilate new technologies into its business processes. There are several barriers to technology adoption within the construction industry that have created a general low tolerance for risk and conservative attitude towards change. Wireless technologies, web-based collaboration, and mobile computing devices have agreeably high potential benefits for the construction industry; however, there is a lack of research and well-documented...
Show moreThe construction industry has been one of the slowest to assimilate new technologies into its business processes. There are several barriers to technology adoption within the construction industry that have created a general low tolerance for risk and conservative attitude towards change. Wireless technologies, web-based collaboration, and mobile computing devices have agreeably high potential benefits for the construction industry; however, there is a lack of research and well-documented projects that stand as proof of their value. An extensive review of wireless technology applications for the construction industry is presented in this thesis, along with a review of Earned Value Management (EVM) and Life Cycle Cost (LCC) analysis. A methodology is developed for applying and assessing wireless technologies for construction project control with EVM incorporated as a project control technique. Data from the Jefferson County High School construction project located in Monticello, Florida, is used to apply the methodology that was developed. The results of this application indicate that the implementation of a wireless IT investment could have reduced the total project cost.
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Date Issued: 2006
Identifier: FSU_migr_etd-0337
Format: Thesis

Title: Promising Approaches to Nitrogen Removal from Septic Effluent Using Nitrification and Denitrification Filters.
Creator: Smith, Leland A., Hilton, Amy Chan, Huang, Wenrui, Chen, Gang, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: Residential wastewater management in urban fringe and rural areas in northwest and north central Florida is commonly accomplished using on-site wastewater treatment systems (OWTSs), typically consisting of septic tank and drainfield combinations, with each residence typically being served by an OWTS that is owned and operated by the individual homeowner. Known and/or potential environmental impacts to ground and surface waters, attributed to use of septic tank and drainfield systems, are...
Show moreResidential wastewater management in urban fringe and rural areas in northwest and north central Florida is commonly accomplished using on-site wastewater treatment systems (OWTSs), typically consisting of septic tank and drainfield combinations, with each residence typically being served by an OWTS that is owned and operated by the individual homeowner. Known and/or potential environmental impacts to ground and surface waters, attributed to use of septic tank and drainfield systems, are currently receiving significant attention from scientific and regulatory communities, in Florida and elsewhere. Effluent nitrogen concentration is typically the main concern because of the tendency of nitrate nitrogen to migrate rapidly in groundwater, and the association of nitrate nitrogen with both human health and environmental effects. Septic effluent nitrification and/or denitrification filters can be equipped with a variety of filter media and can be configured in a variety of different ways to provide better nitrogen removal than is typically achieved by a conventional septic tank and drainfield system alone. There are, however, many variations on this idea, some producing better nitrogen removal results than others. A literature review was conducted to collect information regarding the nitrogen removal performance, operation and maintenance considerations and permitting constraints of septic effluent nitrification and/or denitrification filters in various operating configurations. The results gained in several different studies were reviewed and key design elements were identified. Research into the performance of these filter systems included consideration of filters operating in single pass and recirculating configurations, and combinations thereof. Major septic effluent filter studies that were reviewed for this thesis include: 1. Pulsed Recirculating Sand Filter Systems (Lamb et al., 1987) 2. Anne Arundel County, MD System 1 (Piluk and Hao, 1989; Piluk and Byers, 2001) 3. Anne Arundel County, MD System 2 (Piluk and Byers, 2001) 4. Modified Recirculating Sand Filter (RSF2) system (Sandy et al., 1987) 5. RUCK System (Laak, 1981; Lamb et al., 1987) 6. Non Woven Textile Fabric (NWTF) Filter System (Leverenz et al., 2001) 7. Passive Nitrogen Removal Systems (Smith et al., 2008) Statistical information on permits issued for innovative OWTSs and testing data on nitrogen removal performance of performance-based treatment systems were obtained from the Florida Department of Health (FDOH), and were reviewed for information of relevance to the research objective. The FDOH statistical information reviewed did not indicate numbers of alternative systems permitted, but did include numbers of performance-based treatment systems (PBTSs) and aerobic treatment units (ATUs) permitted. FDOH statistics show that ATUs have been implemented widely, including in many parts of north central and northwest Florida, most notably in Franklin County. PBTSs, however, have not been implemented to a significant degree. Conclusions were drawn relative to specific nitrogen removal technologies and operating configurations that seem promising for potential broad based, near term implementation in septic effluent filter systems in decentralized wastewater management scenarios that are commonly encountered in rural and urban fringe development projects in north central and northwest Florida. Along those lines, the following types of systems were identified as seeming to be particularly promising: 1. Recirculating sand filter (RSF) system equipped with an upflow anoxic filter; and 2. RSF system with quiescent recirculation to an anoxic pump tank. Other technologies and configurations that seem promising but likely in need of testing and evaluation for potential FDOH approval include the following: 1. Passive nitrogen removal systems (PNRSs), as explored by Smith et al. (2008). 2. RSFs in combination with drip irrigation. 3. RSFs in combination with drip irrigation and denitrification enhancement through the use of alternative trench bedding, in order to maintain an abundant supply of carbon in locations where organic carbon supply is poor. Based on a review of the state regulations governing the use of septic tank and drainfield systems and other on-site wastewater treatment systems, the importance of regulatory agency pre-application meetings was stressed as a way to improve the odds of success for a project that may potentially involve the use of an alternative or innovative system. The findings of this thesis support the implementation of septic effluent nitrification and denitrification filter systems in decentralized wastewater management scenarios in rural and urban fringe development projects in north central and northwest Florida, and the expansion of the variety of treatment technologies and configurations that are approved as "alternative systems" under the FDOH Chapter 64E-6, F.A.C. regulations. Finally, FDOH-compiled permitting statistics and performance data suggest that further exploration of unit processes within commercially available PBTSs utilizing packed bed media filters may reveal opportunities for further enhancement of selected systems through application of conclusions drawn from the literature review.
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Date Issued: 2009
Identifier: FSU_migr_etd-0367
Format: Thesis

Title: Optimal Preliminary Roadway Alignment Location: A GIS Approach.
Creator: Awwad, Rasem, AbdelRazig, Yassir, Ping, Virgil, Mussa, Renatus, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: The planning phase in highway development is a very critical phase as it affects the latter phases of the project. During the preliminary planning phase in highway development, a location study is done. This is to try to set alignment alternatives that are cost efficient as far as land and construction costs. This thesis utilizes Geographic Information Systems (GIS) software in order to locate an optimal alignment for a new road connecting two points. Three criteria are taken into...
Show moreThe planning phase in highway development is a very critical phase as it affects the latter phases of the project. During the preliminary planning phase in highway development, a location study is done. This is to try to set alignment alternatives that are cost efficient as far as land and construction costs. This thesis utilizes Geographic Information Systems (GIS) software in order to locate an optimal alignment for a new road connecting two points. Three criteria are taken into consideration; land cost, land slope and environmental features. A methodology is developed for optimizing a roadway alignment based on the three criteria, and is implemented in ArcView 8.1, the most updated GIS software package released by the Environmental Systems Research Institute (ESRI). The base of the process is to convert the study area into a grid or raster, which represents the search space for an optimal location, the Spatial Analyst extension in this software plays a major role. The methodology is applied on two case studies for new alignments in Duval County in the State of Florida. For each case, two optimal alignments are found, one is based on one factor which is the land cost, and another one which combines the land cost and land slope. In both cases the environmental features such as lakes and wetlands are accounted for. For each case study a smooth trial alignment is developed using the indications given by the outputs to overcome their jaggedness. The outputs are then compared to the proposed Florida Department of Transportation alignments. The comparison is based on right-of-way costs for the alignments. For both case studies, the right-of-way costs are found to be significantly lower for the two output optimal alignments, and the smooth trial alignment.
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Date Issued: 2005
Identifier: FSU_migr_etd-0265
Format: Thesis

Title: Deficiency Analysis of Coastal Buildings for Storm Damage Reduction.
Creator: Dowgul, Ronald Walter, Yazdani, Nur, Tawfiq, Kamal, Leszczynska, Dauta, Martinko, Mark, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: Since 1984 the author has provided engineering services to property owners, insurance companies, attorneys, and others. The scope of those services typically included identifying the cause and origin of damage to residential and commercial structures as well as an estimation of the magnitude of damage sustained by those structures. The majority of those damaged structures were located in proximity to a coastal region and have experienced recent exposure to a storm or other weather event. The...
Show moreSince 1984 the author has provided engineering services to property owners, insurance companies, attorneys, and others. The scope of those services typically included identifying the cause and origin of damage to residential and commercial structures as well as an estimation of the magnitude of damage sustained by those structures. The majority of those damaged structures were located in proximity to a coastal region and have experienced recent exposure to a storm or other weather event. The long-term performance of any building (structure) is directly related to, among other things, the design or physical features of the building, construction practices, routine maintenance, and exposure to severe weather events. During periods of increased external loading and water exposure, such as those resulting from severe weather events, deficiencies in design, construction, or maintenance often result in what would otherwise be avoidable building damage. As a result of more than one thousand case studies involving site inspections, it has become apparent that building related deficiencies are often found to exist as a common feature in similar structures. Some of those recurring deficiencies could be eliminated with alternate building design, better construction practices, or proper routine maintenance procedures. Compilation of those case studies has allowed identification and ranking of the occurrence of chronic building problems. Where applicable, proposed remedial solutions are presented for specific building deficiencies or problems identified. It appears that a significant lack of feedback to engineers, architects, and builders exists regarding long term building performance. An increased awareness of existing chronic deficiencies in the design and construction of buildings and a subsequent effort to eliminate those deficiencies is essential to the future performance of new construction, in general, and specifically to the storm survivability of many structures in coastal regions. Much of what has been learned as a result of this analysis can be of considerable value to professionals or future professionals involved in the building design and construction communities.
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Date Issued: 2005
Identifier: FSU_migr_etd-0681
Format: Thesis

Title: The Effect of High Groundwater Level on Pavement Subgrade Performance.
Creator: Zhang, Chaohan, Ping, W. Virgil, Niu, Xufeng, Hilton, Amy Chan, Abichou, Tarek, Abdullah, Makola, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: High groundwater table exerts detrimental effects on the roadway base and the whole pavement. Base clearance guidelines have been developed to prevent water from entering the pavement system in order to reduce its detrimental effects. This dissertation presents an experimental study to evaluate the effects of high groundwater and the moisture on determining pavement base clearance for granular subgrades. Full-scale in-lab and test-pit tests were conducted to simulate pavement profile and...
Show moreHigh groundwater table exerts detrimental effects on the roadway base and the whole pavement. Base clearance guidelines have been developed to prevent water from entering the pavement system in order to reduce its detrimental effects. This dissertation presents an experimental study to evaluate the effects of high groundwater and the moisture on determining pavement base clearance for granular subgrades. Full-scale in-lab and test-pit tests were conducted to simulate pavement profile and vehicle dynamic impact on the pavement. Eight types of granular subgrades were tested for this study. From the test, using layer theory, the results of the resilient modulus for each layer (layer resilient modulus) can be compared with the resilient modulus results from laboratory test. Multiple regression model will be established to predict soil resilient modulus without doing resilient modulus test. The dominant factor or factors of the effect of moisture to resilient modulus will be discussed. The results showed that a 24-inch base clearance was considered adequate for the base protection of most A-3 and A-2 subgrades against high groundwater tables. The lab resilient modulus and layer resilient modulus have the same trend for each soil according to the moisture content change. The SR-70 A-2-4 (14% fines) soil was the most susceptible to the change of groundwater table than the other soils. The percent of fines or the percent of clays of subgrade soil is not good indicator to measure the influence of moisture effect on the resilient modulus. The coefficient of uniformity and coefficient of curvature of the subgrade gradations, which better represent the whole shape of the gradation curve, are better indicators of the effect of moisture to modulus.
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Date Issued: 2004
Identifier: FSU_migr_etd-0545
Format: Thesis

Title: Evaluation and Enhancement of Electro-Kinetic Technology for Remediation of Chromium Copper Arsenic from Clayey Soil.
Creator: Ahmad, Hafiz, Leszczynska, Danuta, Tull, James F., Dzurik, Andrew, Chan-Hilton, Amy, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: A relatively new technique of electro-kinetic remediation is examined to evaluate and enhance removal of residual of the CCA (chromated copper arsenate) from clayey soil. A short duration (25-hours) treatment approach was initiated for this purpose. Laboratory 1-D column tests were performed on kaolin soil under the influence of DC electric field. Different chemicals (acid, alkali and oxidizing agents) and tap water were purged through electro-osmotic flow to enhance chromium, copper, arsenic...
Show moreA relatively new technique of electro-kinetic remediation is examined to evaluate and enhance removal of residual of the CCA (chromated copper arsenate) from clayey soil. A short duration (25-hours) treatment approach was initiated for this purpose. Laboratory 1-D column tests were performed on kaolin soil under the influence of DC electric field. Different chemicals (acid, alkali and oxidizing agents) and tap water were purged through electro-osmotic flow to enhance chromium, copper, arsenic remediation. Configuration of electrodes/reactor setup was also adjusted to improve the removal efficiency of the CCA chemicals by inducing buoyancy with electro-osmotic flow. Interesting results were obtained showing up to 78% of arsenic and 72% copper removal by purging sodium hypo-chlorite (NaOCl). Sodium hydroxide (NaOH) purging also indicated enhanced removal with 74% arsenic and 72% copper removal. It was difficult to remove chromium and maximum removal was only 3.75% when the soil was purged with tap water. The batch experiments show that with respect to individual contaminant remediation, the removal efficiency increases many times when contaminants in the soil are in mixed-form. Inclined reactor setup showed enhanced electro-osmotic flow due to the effect of buoyancy. A model combining main phenomena of contaminant movement: electro-migration, electro-osmosis, diffusion, and buoyancy was developed for a small Debye length. The model predicts the behavior of pH, which is an important parameter that governs the migration of contaminants. Calculation based on the model showed excellent agreement when compared with the pH profile of experimental data of tap water purging for copper remediation. Although additional modeling and experimentation is needed, the results of this thesis demonstrate that electro-kinetic remediation with suitable purging chemicals may offer enhanced removal of polluted soil.
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Date Issued: 2004
Identifier: FSU_migr_etd-0018
Format: Thesis

Title: A Multi-Criteria Approach for Rating Roadway Sustainability.
Creator: Campbell, Ashley J., Sobanjo, John O., Spainhour, Lisa, Chen, Gang, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: "Green engineering" is the newest technology implemented for sustainability in the design of buildings and most recently highways. Sustainability concepts applied to the design and construction of roadways includes long term planning, new technologies and methods, construction management techniques and resource reuse. Green engineering is part of the global goal of long-term sustainability, which is to meet the needs of today without compromising those of the future. Leadership in Energy and...
Show more"Green engineering" is the newest technology implemented for sustainability in the design of buildings and most recently highways. Sustainability concepts applied to the design and construction of roadways includes long term planning, new technologies and methods, construction management techniques and resource reuse. Green engineering is part of the global goal of long-term sustainability, which is to meet the needs of today without compromising those of the future. Leadership in Energy and Environmental Design (LEED®) rating systems have been heavily promoted and utilized in the construction industry, but only with applications to buildings. There is no such criteria for rating roadway construction. Only one documented attempt has been made to adapt the LEED rating system to highway construction but with limited results. While predominantly used and accepted, the LEED rating points are not quantitative and are not based on any traditional decision making theory. This research presents an evaluation of using the LEED rating system techniques for highway construction. A multi-criteria decision making model (MCDM) is then formulated as a framework for evaluating sustainability in roadway construction. Within Leon County, Blueprint 2000 is an intergovernmental organization to efficiently manage and plan roadway construction projects within Tallahassee, Florida. In cooperation with Blueprint 2000, one of their projects will be used as the local sustainable roadway example. This project will serve as the case study and be evaluated for successful applications of sustainable engineering utilized during roadway design and construction. This research will also include an analysis of the multi-criteria rating system developed on a local roadway project. Research will be comprehensive on the topics of stormwater design, erosion control and the usage of various construction materials. The completion of this research will offer a new insight into rating sustainability and also on both new technologies and innovative practices within the transportation and construction management fields.
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Date Issued: 2009
Identifier: FSU_migr_etd-0099
Format: Thesis

Title: Evaluation of Age as a Contributing Factor for Fatal Crashes in the State of Florida.
Creator: Alam, Bhuiyan Monwar, Spainhour, Lisa K., Ping, Virgil, AbdelRazig, Yassir, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: The study investigates the age of at-fault drivers as a contributing factor for fatal crashes in Florida. The main objective of the research was to provide an in-depth analysis of the relationships between the ages of the at-fault drivers and different aspects of roadway, traffic, weather, and other related contributing factors, and recommend various countermeasures, both behavioral and roadway-related so that appropriate actions can be initiated to improve safety on Florida's highways. It...
Show moreThe study investigates the age of at-fault drivers as a contributing factor for fatal crashes in Florida. The main objective of the research was to provide an in-depth analysis of the relationships between the ages of the at-fault drivers and different aspects of roadway, traffic, weather, and other related contributing factors, and recommend various countermeasures, both behavioral and roadway-related so that appropriate actions can be initiated to improve safety on Florida's highways. It also investigates the relationships between age vs. race, and age vs. sex. The study focuses on the driving behaviors of the younger (=years) and older (65-74 years, and >=75 years) drivers although the data of middle-age (25-64 years) drivers are also analyzed.=75 years) drivers although the data of middle-age (25-64 years) drivers are also analyzed. The younger and older drivers of both sexes are more likely to cause fatal crashes compared to the 'average' drivers. Among these, the female oldest (>=75 years) drivers are at highest level of vulnerability of causing fatal crashes followed by younger male drivers. The younger drivers of all races and only the white older drivers are more likely to cause such crashes. The older drivers of black, Hispanic, and 'other' races are less likely to cause fatal crashes compared to the 'average' drivers. In case of number of vehicles involved in crashes, the younger drivers are more likely to contribute to 1-vehicle, 2-vehicle, 3-vehicle, and >=4-vehicle crashes while the older drivers are also more likely to cause all of these types, except 1-vehicle crashes.=75 years) drivers are at highest level of vulnerability of causing fatal crashes followed by younger male drivers. The younger drivers of all races and only the white older drivers are more likely to cause such crashes. The older drivers of black, Hispanic, and 'other' races are less likely to cause fatal crashes compared to the 'average' drivers. In case of number of vehicles involved in crashes, the younger drivers are more likely to contribute to 1-vehicle, 2-vehicle, 3-vehicle, and >=4-vehicle crashes while the older drivers are also more likely to cause all of these types, except 1-vehicle crashes.=4-vehicle crashes while the older drivers are also more likely to cause all of these types, except 1-vehicle crashes. The study finds significant impacts of age of the at-fault drivers on contributing factors like crash hour, lighting conditions, road grades, road surface types, site locations, and vehicle speed while no significant impacts are found on road surface conditions, weather conditions, lane types (left, right, etc.), and shoulder types. The study reveals that the older drivers are involved in more intersection crashes than non-intersection crashes while the situation is opposite for the younger drivers. Among others the reasons for intersection crashes by the older drivers include misjudgment of speeds of the oncoming vehicles (18.0%), failure to observe the vehicle/all sides before approaching the intersection (17.0%), disregarding traffic signals (13.4%), and improper left turn (12.4%) are four major contributing factors each of which contributes to >=10% of intersection crashes by the older drivers. In case of non-intersection crashes, the study reveals that sudden loss of control contributes to more than one-third (37.1%) while driving under the influence of alcohol contributes to almost one-fifth (18.6%) of such crashes.=10% of intersection crashes by the older drivers. In case of non-intersection crashes, the study reveals that sudden loss of control contributes to more than one-third (37.1%) while driving under the influence of alcohol contributes to almost one-fifth (18.6%) of such crashes. It is evident that driving under the influence of alcohol (28.4%), exceeding safe speed limits (19.7%), and loss of control (19.7%) by the younger drivers are three major causes of fatal crashes in Florida, specially the 1-vehicle, high-speed, pedestrian/bicycle related, and loss of control type crashes. Among others disregarding traffic signals (6.6%) and failure to stop to avoid rear-end collision (6.3%) contribute to >=5% while failure to observe vehicles/all sides (3.3%), disregarding stop signs (3.0%), improper left turn (2.3%), and improper lane change (2.0%) contribute to >=2% of crashes on highways by the younger drivers whether at intersection or non-intersection. In case of intersection crashes, driving under the influence of alcohol (23.9%), disregarding traffic signals (18.8%), and exceeding safe speed limits (12.3%) come out as three major contributing causes. Other important contributing factors are disregarding stop signs, failure to observe vehicles/all sides, failure to stop to avoid rear-end collision, improper left turn, and loss of control that contribute to >=5% of intersection crashes. On the other hand, driving under the influence of alcohol (30.7%), loss of control of the vehicle (27.6%), exceeding safe speed limits (23.7%), and failure to stop the vehicle to avoid rear-end collision (5.8%) come out as four major contributing factors that cause >=5% of the non-intersection crashes by these drivers.=5% while failure to observe vehicles/all sides (3.3%), disregarding stop signs (3.0%), improper left turn (2.3%), and improper lane change (2.0%) contribute to >=2% of crashes on highways by the younger drivers whether at intersection or non-intersection. In case of intersection crashes, driving under the influence of alcohol (23.9%), disregarding traffic signals (18.8%), and exceeding safe speed limits (12.3%) come out as three major contributing causes. Other important contributing factors are disregarding stop signs, failure to observe vehicles/all sides, failure to stop to avoid rear-end collision, improper left turn, and loss of control that contribute to >=5% of intersection crashes. On the other hand, driving under the influence of alcohol (30.7%), loss of control of the vehicle (27.6%), exceeding safe speed limits (23.7%), and failure to stop the vehicle to avoid rear-end collision (5.8%) come out as four major contributing factors that cause >=5% of the non-intersection crashes by these drivers.=2% of crashes on highways by the younger drivers whether at intersection or non-intersection. In case of intersection crashes, driving under the influence of alcohol (23.9%), disregarding traffic signals (18.8%), and exceeding safe speed limits (12.3%) come out as three major contributing causes. Other important contributing factors are disregarding stop signs, failure to observe vehicles/all sides, failure to stop to avoid rear-end collision, improper left turn, and loss of control that contribute to >=5% of intersection crashes. On the other hand, driving under the influence of alcohol (30.7%), loss of control of the vehicle (27.6%), exceeding safe speed limits (23.7%), and failure to stop the vehicle to avoid rear-end collision (5.8%) come out as four major contributing factors that cause >=5% of the non-intersection crashes by these drivers.=5% of intersection crashes. On the other hand, driving under the influence of alcohol (30.7%), loss of control of the vehicle (27.6%), exceeding safe speed limits (23.7%), and failure to stop the vehicle to avoid rear-end collision (5.8%) come out as four major contributing factors that cause >=5% of the non-intersection crashes by these drivers.=5% of the non-intersection crashes by these drivers. In brief, the study reveals that driving under the influence of alcohol is the sole important contributing factor for all types of crashes by both younger and older drivers, except the intersection crashes by the older drivers for which misjudgment of speed and failure to observe are the major contributing factors. Other important factors are exceeding safe speed limits, disregarding traffic signals, and sudden loss of control of the vehicles. Another important finding of the study is that the investigation officers have tendency to frequently use the terms 'careless driving' for the younger-non-intersection crashes and 'failure to yield right of way' for older-intersection crashes. Finally, the study finds that about half of the at-fault drivers do not wear safety equipments that cause severe fatality. The study recommends that more efficient and frequent public transit services should be provided to the older drivers, and their driving licenses should be renewed every year to lessen the number of older drivers on the streets. On the other hand, training and educational programs should be initiated for the younger drivers. Stricter laws should be introduced for driving under the influence of alcohol/drug, driving at unsafe speeds, not wearing seat belts, and other offences so the younger drivers act with more responsibility on the streets. The numbers of traffic and billboard signs should also be kept at the minimum so the older drivers are not confused with unnecessary signs.
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Date Issued: 2005
Identifier: FSU_migr_etd-0044
Format: Thesis

Title: Long-Term Performance of Epoxy Filled Steel Grate Decking.
Creator: Akaro, Cathbert, Mtenga, Primus V., Tawfiq, Kamal S., Sobanjo, John O., Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: In the Florida State highway system there are 11,100 bridges (6,300 State bridges and 4,800 local bridges). The highway system includes 98 movable bridges, which are located within seven geographic districts. These bridge decks are constructed with steel open metal grate decking to reduce the weight of the superstructure and load carried by the substructure. When traffic traverses on the bridge deck systems, a significant level of noise is generated. This noise has caused some discomfort and...
Show moreIn the Florida State highway system there are 11,100 bridges (6,300 State bridges and 4,800 local bridges). The highway system includes 98 movable bridges, which are located within seven geographic districts. These bridge decks are constructed with steel open metal grate decking to reduce the weight of the superstructure and load carried by the substructure. When traffic traverses on the bridge deck systems, a significant level of noise is generated. This noise has caused some discomfort and has become a nuisance to the public, especially in regard to those bridges located near populated areas. Because of the problem, it has been suggested that filling the open grate with epoxy and fine aggregate broadcasted on it will increase the friction resistance and reduce the noise from bridge deck systems. For new bridges, concrete filling (exodermic deck) has been used, taking the extra weight from the concrete into consideration during the design stage. For the older bridges, however, the extra concrete weight was not considered in the design stage. Thus, the use of epoxy materials, which are lighter than concrete, is necessary in existing decks in order to remain within the load-carrying capacity of the other components of the bridge. The primary objective of this study was to address the performance of the filled steel deck systems, the behavior and effect of repetitive thermal loads (temperatures below and above normal ambient temperature) to the open steel grid deck systems that were filled with epoxy resin. The deck systems filled with epoxy materials were subjected to accelerated climate chamber to simulate similar or extreme field conditions. Experimental results found that the performance of the open filled decks depends on the weather conditions. Under temperatures above normal ambient temperature, the interfacial region showed severe delamination compared to temperatures below normal ambient temperature. Also the study found that the performances at the interfacial region were affected by the number of cycles for both low and high temperatures.
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Date Issued: 2006
Identifier: FSU_migr_etd-0144
Format: Thesis

Title: Optimization of Groundwater Long-Term Monitoring Network Optimization of Groundwater Long-Term Monitoring Network with Ant Colony Optimization with Ant Colony Optimization.
Creator: Liu, Xiaoli, Chen, Gang, Ye, Ming, Wang, Xiaoqiang, Hilton, Amy B. Chan, Huang, Wenrui, Tang, Youneng, Florida State University, College of Engineering, Department of Civil and...
Show moreLiu, Xiaoli, Chen, Gang, Ye, Ming, Wang, Xiaoqiang, Hilton, Amy B. Chan, Huang, Wenrui, Tang, Youneng, Florida State University, College of Engineering, Department of Civil and Environmental Engineering
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Abstract/Description: Groundwater remediation is conducted in polluted sites to remove contaminants and to restore ground water quality. After remediation goals are achieved, long-term groundwater monitoring (LTM) that can span decades is required to assess the concentration of residual contaminants and to avoid the risk of human health and environment. On large remediation sites, the cost for maintaining a LTM network, collecting samples, conducting water quality lab analysis can be a significant, persistent and...
Show moreGroundwater remediation is conducted in polluted sites to remove contaminants and to restore ground water quality. After remediation goals are achieved, long-term groundwater monitoring (LTM) that can span decades is required to assess the concentration of residual contaminants and to avoid the risk of human health and environment. On large remediation sites, the cost for maintaining a LTM network, collecting samples, conducting water quality lab analysis can be a significant, persistent and growing financial burden for the private entities and government agencies who are responsible for environmental remediation projects. LTM network optimization offers an opportunity to improve the cost-effectiveness of the LTM effort while meeting data accuracy requirements. The optimization includes identifying the redundancy in the monitoring network, and recommending changes to protect against potential impacts to the public and the environment. This study develops a variant ant colony optimization (VACO) method, using ordinary kriging (OK) or inverse distance weighting (IDW) for data interpolation, to identify optimal LTM networks that minimize the cost of LTM by reducing the number of monitoring locations with minimum overall data loss. ACO is a global stochastic search method inspired by the collective problem-solving ability of a colony of ants as they search for the most efficient routes from their nests to food sources. The performance of ACO variant (VACO) developed in this study is evaluated separately in two test cases. In the first case, VACO is used to solve a simplified traveling sales person problem. In the second case, both enumeration method and VACO are employed for optimization of a synthetic long term monitoring network of 73 wells generated from a groundwater transport simulation model. The two sets of test show that the VACO performs well for optimization problems. The VACO is finally adopted for the optimization of a long term monitoring network of 30 wells in Logistic Center, Washington, with the data interpolation methods of inverse distance weighing, ordinary kriging, and modified inverse distance weighing which is developed in this study. The optimization results are analyzed and group of ideal redundant wells identified. The conclusion of this study is summarized at the end, and future work is suggested.
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Date Issued: 2017
Identifier: FSU_FALL2017_Liu_fsu_0071E_14254
Format: Thesis

Title: Hydrogen Sulfide Attenuation within Landfill Covers.
Creator: Green, Stefan Larae, Abichou, Tarek, Clark, Clayton J., Chen, Gang, Florida State University, FAMU-FSU College of Engineering, Department of Civil and Environmental Engineering
Abstract/Description: There has been much research done on the reduction, or attenuation, of hydrogen sulfide (H2S), particularly within landfill cover soils, as H2S can cause many issues when exposed to the atmosphere. The objective of this research study was to understand hydrogen sulfide (H2S) attenuation within landfill cover soils, and to use mass balancing to determine how much sulfur was retained within each layer of test pad. Both of these were completed through 403 days of monitoring three 65 feet by 35...
Show moreThere has been much research done on the reduction, or attenuation, of hydrogen sulfide (H2S), particularly within landfill cover soils, as H2S can cause many issues when exposed to the atmosphere. The objective of this research study was to understand hydrogen sulfide (H2S) attenuation within landfill cover soils, and to use mass balancing to determine how much sulfur was retained within each layer of test pad. Both of these were completed through 403 days of monitoring three 65 feet by 35 feet lysimeter test pads constructed at the Riverbend Landfill. Test Pad 1 was constructed with 18 inches of local soil and an underlying 6 inch gravel layer. Test Pad 2 was constructed with 12 inches of compost, 6 inches of local soil and an underlying 6 inch gravel layer. Test Pad 3 was constructed with 6 inches of local soil and an underlying 6 inch gravel layer. Monitoring on Test Pad 3 was stopped on April 27th, 2015 due to erosion of the 6 inch soil layer, while Test Pads 1 and 2 were monitored until July 20th, 2015. Readings of landfill gas and H2S inflow, and bottom landfill gas and H2S concentrations were taken in each testing pad on a weekly basis. Bottom H2S loading into the soil layer and top H2S emissions from the soil layer were also measured to determine the removal efficiency of H2S. The average H2S removal efficiency of the test pads is 95%, with Test Pad 1 having a removal efficiency of 99%, Test Pad 2 having a removal efficiency of 99%, and Test Pad 3 having a removal efficiency of 82%. Six soil samples and five water samples were taken to measure sulfur concentration within the testing pads. Soil samples were also taken within each of the layers of each testing location within each test pad to determine the soil type and the water content of each soil layer. Mass balance was calculated by taking the amount of sulfur loaded into the bottom of each testing pad, and subtracting the sum of sulfur loaded into the soil cover, sulfur emitted from the soil cover into the atmosphere, and sulfur removed from the system with water as sulfate. Test Pads 1 and 2 yielded similar results, both retaining about 6000 grams of sulfur within their cover layers, while the results from Test Pad 3 suggest that more sulfur was removed from the system than was originally pushed into the system, which is not possible and suggests errors with either testing methods or the testing pad itself. While the concentrations of sulfur within each test pad layer were measured, there were concerns with their dependability that caused them to not be used to determine the amount of sulfur in each layer.
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Date Issued: 2015
Identifier: FSU_2015fall_Green_fsu_0071N_12959
Format: Thesis

Title: Parametric Optimization of Steel Floor System Cost Using Evolver.
Creator: Platt, Bethany Susan, Mtenga, Primus V., Sobanjo, John O., Tawfiq, Kamal S., Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: This paper examines the application of Evolver, a genetic algorithm (GA) solving program, in a three-parameter optimization of a steel truss floor system with a concrete slab floor deck. The floor system is comprised of truss girders supporting beams running in a direction perpendicular to the truss girders with a composite floor deck along the top. Using Evolver, three parameters are optimized for two truss girder topologies in order to find the least cost floor system. The weight of the...
Show moreThis paper examines the application of Evolver, a genetic algorithm (GA) solving program, in a three-parameter optimization of a steel truss floor system with a concrete slab floor deck. The floor system is comprised of truss girders supporting beams running in a direction perpendicular to the truss girders with a composite floor deck along the top. Using Evolver, three parameters are optimized for two truss girder topologies in order to find the least cost floor system. The weight of the structural members is correlated to the expenses of material, labor, equipment, and overhead and profit required for the construction of the floor through information given by Means Building Construction Cost Data and interviews with steel fabricators. This procedure may be modified to optimize the cost of any floor area size that may use different truss girder topologies, beam sections, and connections. Parametric optimization is defined in this paper as the combination of configuration, size, and topology optimization of a truss girder, the size optimization of beams, and the optimization of the spacings of both beams and truss girders in the system. A discrete set of values has been selected for each variable that makes up the search space from which all solutions to the problem exist. A GA is a search algorithm, incorporated to quickly explore a wide range of answers and focus on better areas of the search space to find improved solutions.
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Date Issued: 2006
Identifier: FSU_migr_etd-0645
Format: Thesis

Title: Fuzzy Control of Magnetorheological Dampers for Vibration Reduction of Seismically Excited Structures.
Creator: Wilson, Claudia Mara Dias, Abdullah, Makola M., Collins, Emmanuel G., Spainhour, Lisa K., Yazdani, Nur, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: Since civil structures have little damping capability, extensive damage and even failure often occur when they are subjected to seismic excitations. Control devices have therefore been developed and implemented to dissipate energy from earthquakes and reduce structural vibrations. Magnetorheological (MR) dampers are examples of such devices and consist of a hydraulic cylinder containing a solution that, in the presence of a magnetic field, can reversibly change from viscous fluid to semi...
Show moreSince civil structures have little damping capability, extensive damage and even failure often occur when they are subjected to seismic excitations. Control devices have therefore been developed and implemented to dissipate energy from earthquakes and reduce structural vibrations. Magnetorheological (MR) dampers are examples of such devices and consist of a hydraulic cylinder containing a solution that, in the presence of a magnetic field, can reversibly change from viscous fluid to semi-solid. The objective of this research is to develop fuzzy controllers to regulate the damping properties of MR dampers and reduce structural responses of single degree-of-freedom seismically excited structures. Three fuzzy controllers were therefore designed and their effectiveness evaluated through series of numerical simulations. Since fuzzy control uses expert knowledge instead of differential equations, it allows for the development of simple and robust algorithms that do not require information on plant's structural and vibration characteristics. They are therefore an attractive alternative for controlling systems that are complex, nonlinear, or that contain ambiguity or vagueness. The first algorithm proposed is a fuzzy control system with two inputs: structural displacement and velocity. The second is referred to as gain-scheduled fuzzy control and varies the velocity input scaling factor according to incoming ground acceleration. The last one, self-tuning fuzzy control, uses a fuzzy inference mechanism based on ground acceleration intensity and building displacement to adjust the velocity input scaling factor. Robustness of these controllers to changes in seismic motions and structural characteristics were evaluated by subjecting two different buildings controlled by each of these strategies to a wide range of earthquake records. Results show that the algorithms proposed effectively reduced responses of both structures to a wide range of seismic motions. They were also found to be robust to changes in ground excitations and structural characteristics. In addition, adjusting the velocity input scaling factor according to ground acceleration intensity considerably improved the controller's ability to reduce structural vibrations, since both the gain-scheduled and the self-tuning fuzzy algorithms reduced structural responses more effectively than the fuzzy controller with constant scaling factors. Finally, the self-tuning controller outperformed all other strategies for most earthquakes considered.
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Date Issued: 2005
Identifier: FSU_migr_etd-0891
Format: Thesis

Title: Development of a Measure of Effectiveness for the Florida Elder Road User Program.
Creator: Pierre, Velouse, Spainhour, Lisa, Mussa, Renatus, Sobanjo, John, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: Older drivers may have more difficulty than the general driving public in attending to the driving task, and they may be slower at processing information, especially when required to make complex decisions. Traffic crashes caused by elderly drivers have been attributed to neglect of, or inattention to, relevant information from road signs, as well as to other cars and pedestrians on the road. This is especially true at intersections. To combat these safety issues, implementation of the...
Show moreOlder drivers may have more difficulty than the general driving public in attending to the driving task, and they may be slower at processing information, especially when required to make complex decisions. Traffic crashes caused by elderly drivers have been attributed to neglect of, or inattention to, relevant information from road signs, as well as to other cars and pedestrians on the road. This is especially true at intersections. To combat these safety issues, implementation of the Florida Elder Road User Program began on state-maintained roads. This program sought to improve roadways by increasing visibility and adding advanced signage and reflective pavement markings. This study sought to evaluate the effectiveness of the Florida Elder Road User Program by building a crash prediction model that examines older driver crash frequency using variables obtained from quantitative variables such as maximum posted speed limit and qualitative variables such as sign visibility. Crash data was collected for 601 intersections in the state of Florida for the years 2000-2002. Detailed analysis of geometric and traffic data collected from various resources, such as crash reports, Roadway Characteristics Inventory data, and video log archives, was performed to determine the correlation between these independent factors and crash frequency. The crash distribution was found to be negative binomial; the model needed to be inflated due to the presence of many zero-crash intersections. Therefore, a Zero-Inflated Negative Binomial (ZINB) crash prediction model was developed. The response variable in the model was crash frequency, and independent variables included roadway geometrics, traffic characteristics, and intersection characteristics. Crash frequency was found to have a very strong relationship with most of the independent variables as indicated by their p-values. Traffic volumes, signalization, and sign visibility had positive coefficients, indicating that, higher traffic volumes, signalized intersections, and sign visibility were associated with increased crash frequency. Many of the improvements, including sign visibility and reflective pavement markers listed in the Florida Elder Road User Program were found to be significant but did not reduce elderly driver crashes, proving that the program is not effective.
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Date Issued: 2006
Identifier: FSU_migr_etd-0792
Format: Thesis

Title: Methane Emission and Oxidation Through Landfill Covers.
Creator: Yuan, Lei, Abichou, Tarek, Chanton, Jeffrey, Tawfiq, Kamal, Ping, Wei-Chou V., Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: This dissertation presents the work of investigating methane emission and oxidation through landfill covers. Methane as a major source of greenhouse and is being emitted from solid waste landfill at a tremendous rates. These emissions could be mitigated by methanotrophic bacteria in enriched and non-enriched soil covers. Compost biofilters were constructed to study the methane oxidation capacity of compost. The aged chipped yard waste compost was obtained from Leon County landfill (Florida,...
Show moreThis dissertation presents the work of investigating methane emission and oxidation through landfill covers. Methane as a major source of greenhouse and is being emitted from solid waste landfill at a tremendous rates. These emissions could be mitigated by methanotrophic bacteria in enriched and non-enriched soil covers. Compost biofilters were constructed to study the methane oxidation capacity of compost. The aged chipped yard waste compost was obtained from Leon County landfill (Florida, USA). A one-dimensional dynamical numerical model was developed to simulate the methane transport and oxidation through the biofilter. This model was designed to incorporate dynamic parameters and use flux bottom boundary, which is measured by a flow meter. General agreements of methane outflux and oxidations were obtained between model simulation and experimental data. Field scale control cells and biocells were evaluated in the same landfill for methane emission and oxidation. Methane oxidation in biocells was significantly higher than in control cells. When outliers were removed, methane emission from biocells was significant less than from control cells. A numerical model was developed to separate blockage of the thicker biocells cover and the biological oxidation. Results showed that the low emission from biocells is caused by blockage of soil cover underneath the compost cover as well the high oxidation capacity of this compost cover. An additional modeling investigation was conducted to evaluate how landfill final earthen cover's construction and climate conditions affect methane emission and oxidation under different boundary condition and different soil oxidation capacities. This numerical model combined a water and heat flow model (HYDRUS1D) and a gas transport and oxidation model. Simulations showed that soil covers in subhumid areas can prevent high methane emission with blockage and decent oxidation capacity. In semi-arid sites, higher emission was obtained due to the higher air filled void space of the soil. Oxidation capacities in semi-arid sites are higher than those in subhumid sites since influxes of methane are higher in semiarid sites. High pressure underneath the cover caused higher emission in all sites. Even with active gas collection system (vacuum pressure), emissions were significant in semiarid climates.
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Date Issued: 2006
Identifier: FSU_migr_etd-0919
Format: Thesis

Title: Removal of Powdered Activated Carbon by Cloth Tertiary Filters.
Creator: Madden, Brandon Cale, Ahmad, Hafiz, Chen, Gang, Tang, Youneng, Florida State University, College of Engineering, Department of Civil and Environmental Engineering
Abstract/Description: Water conservation, wastewater treatment regulations, and the use of reclaimed/reuse water supplies have been on a collision course since society’s demand began outstripping the supply of fresh water. As potable water demand has risen, engineers have looked toward Waste Water Treatment Plants (WWTP) to alleviate the stress placed upon aquifers and surface water sources. Direct Potable Reuse (DPR), Indirect Potable Reuse (IPR) and Reuse/Reclaimed systems all conserve water; however, they also...
Show moreWater conservation, wastewater treatment regulations, and the use of reclaimed/reuse water supplies have been on a collision course since society’s demand began outstripping the supply of fresh water. As potable water demand has risen, engineers have looked toward Waste Water Treatment Plants (WWTP) to alleviate the stress placed upon aquifers and surface water sources. Direct Potable Reuse (DPR), Indirect Potable Reuse (IPR) and Reuse/Reclaimed systems all conserve water; however, they also unintentionally conserve pollutants. The widespread use of WWTP effluent conservation requires additional treatment options such as Activated Carbon treatment to further treat plant effluent. Powdered Activated Carbon (PAC) has shown promise as a treatment method to reduce pollutants but challenges remain in effectively applying PAC to a wastewater stream. Of particular concern is the application of PAC to existing facilities in which the existing hydraulic profile does not allow the use of large sedimentation tanks normally associated with PAC use in potable water applications. Cloth Media Filtration (CMF) is an existing treatment process that has seen significant saturation into the WWTP market in the United States since being introduced in 1991. While mostly targeted at tertiary treatment, alternate processes such as primary filtration and storm water treatment are now being pursued. It is suspected that CMF will capture and retain Powdered Activated Carbon (PAC) in which the two processes could be combined in order to produce an energy friendly and cost competitive approach to pollutant reductions. This research examines the feasibility of application of PAC into existing hydraulic profiles by using inline injection and its quick removal by Cloth Media Filtration (CMF). One of the most challenging aspects of PAC usage is its removal, which can be facilitated by a commercial CMF. A bench sized cloth media filter was constructed and then operated in a side stream manner with a real-world wastewater treatment train. The results show excellent performance of the designed CMF. The removal of two commercially available PACs was more than 70% within a short time using the existing hydraulic conditions of the plant. Additionally, using the backwash rates and solids removal rates, it was determined that CMF performs as an acceptable means of removal for PAC in a WWTP.
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Date Issued: 2017
Identifier: FSU_SUMMER2017_Madden_fsu_0071N_14114
Format: Thesis

Title: Production and Modification of Biochar for Organics Removal and Soil Ammendment.
Creator: Brown, Douglas Lane, Ahmad, Hafiz, Chen, Gang, Tang, Youneng, Florida State University, FAMU-FSU College of Engineering, Department of Civil and Environmental Engineering
Abstract/Description: The use of biochar as a soil amendment for agricultural purposes in various cultures has been around for centuries, perhaps millennia. This study seeks to advance this practice by investigating the use of engineered biochar, by chemical impregnation, as a means of optimizing the nutrient retaining properties of soil. As a potentially major source of nutrients are found in wastewater, the biochar is also checked for its viability of pre-loading said char with nutrients, by first using it as a...
Show moreThe use of biochar as a soil amendment for agricultural purposes in various cultures has been around for centuries, perhaps millennia. This study seeks to advance this practice by investigating the use of engineered biochar, by chemical impregnation, as a means of optimizing the nutrient retaining properties of soil. As a potentially major source of nutrients are found in wastewater, the biochar is also checked for its viability of pre-loading said char with nutrients, by first using it as a means to clean wastewater. First biochar (BC) is used to produce activated carbon (AC) and comparisons are made between the BC and AC in their ability to remove organics from wastewater, then the biochar is chemically modified with three chemicals, Ferrous sulfate Heptahydrate (Copperas), Calcium Chloride (Ice Bite), and Aluminum Potassium Sulfate Dodecahydrate (Alum), and tested for nutrient (orthophosphate and nitrate) sorption. The biochar failed in its unaltered form of removing organics (COD) from wastewater, actually adding COD into the solution. Only when the char was turned into activated carbon did it express the ability to remove COD. The chemically modified chars showed promise in their ability to adsorb nutrients (phosphate and nitrate) from solution (wastewater), as well as enhance the retention of said nutrients (particularly phosphate) within a sandy soil. The biochar amendments also significantly increased the water holding capacity of the sandy soil, regardless of BC type, by no less than 10%.
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Date Issued: 2018
Identifier: 2018_Su_Brown_fsu_0071N_14794
Format: Thesis

Title: The Effects of Silver Nanoparticles on Wastewater Treatment and Escherichia Coli Growth.
Creator: Perez, Michael, Department of Civil and Environmental Engineering
Abstract/Description: Nanomaterials and their increasing use in manufactured products are of great concern to wastewater treatment systems and the environment. Nanosilver has become one of the most popular nanoparticles due to its many applications and relatively low manufacturing costs. It is currently being used for a wide variety of commercial products including medical applications, water purification, antimicrobial uses, paints, coatings, food packaging. Impregnating other materials with silver nanoparticles...
Show moreNanomaterials and their increasing use in manufactured products are of great concern to wastewater treatment systems and the environment. Nanosilver has become one of the most popular nanoparticles due to its many applications and relatively low manufacturing costs. It is currently being used for a wide variety of commercial products including medical applications, water purification, antimicrobial uses, paints, coatings, food packaging. Impregnating other materials with silver nanoparticles is a practical way to exploit the germ fighting properties of silver (Nanotechnology 2006). In clothing such as socks, nanosilver may restrict the growth of odor causing bacteria (Benn, Nanoparticle Silver Released into Water from Commercially Available Sock Fabrics 2008). These impregnated socks however have been shown to release large amounts of n-Ag particles when washing. These free nanoparticles easily enter wastewater collection systems. The microbial inhibitory effects of nanosilver were evaluated by studying the effects Escherichia coli (E. coli) growth under nanosilver presence. Results showed that E. coli bacterial growth was inhibited when nanosilver was introduced. This may have detrimental impacts on aerobic wastewater treatment systems which rely on bacteria to break down organic material. Systems may become inefficient and obsolete with an increasing prevalence of nanosilver in sewage.
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Date Issued: 2012
Identifier: FSU_migr_uhm-0068
Format: Thesis

Title: Biological Reduction of Selenate and Recovery of Elemental Selenium from Wastewater in a Continuous-Flow System.
Creator: Adedeji, Itunu Comfort, Tang, Youneng, Chen, Gang, Clark, Clayton J., Florida State University, FAMU-FSU College of Engineering, Department of Civil and Environmental Engineering
Abstract/Description: The biological degradation of selenate to elemental selenium and recovery of valuable selenium nanoparticles has been extensively studied and reported by researchers throughout literature. The major challenges in degradation and recovery processes are the reduction of high concentration of selenium oxyanions and effective separation of bacterial cells and sludge from these economically beneficial elemental selenium nanoparticles. This study seeks to investigate the efficacy of a novel...
Show moreThe biological degradation of selenate to elemental selenium and recovery of valuable selenium nanoparticles has been extensively studied and reported by researchers throughout literature. The major challenges in degradation and recovery processes are the reduction of high concentration of selenium oxyanions and effective separation of bacterial cells and sludge from these economically beneficial elemental selenium nanoparticles. This study seeks to investigate the efficacy of a novel combination system comprising a biological reactor, a separating chamber and a tangential-flow ultrafiltration module (TFU). The biological reactor was investigated for its ability to reduce selenate at high loading rates. The separating chamber containing the inclined bacterium-nanoparticle separator was investigated for its ability to separate bacteria from nanoparticles. The TFU was investigated for its ability to induce a water-bacterium-nanoparticles separation even at high selenate loading rates. The reactor system worked in synergism to remove high concentration of selenate from wastewater and simultaneously recover the valuable elemental selenium nanoparticles thereby eliminating the additional use of chemicals or post-treatment operations.
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Date Issued: 2018
Identifier: 2018_Fall_Adedeji_fsu_0071N_14970
Format: Thesis

Title: Degradation of Perfluorooctanoic Acid by a Non-Thermal Plasma Reactor and Bio-Reactors.
Creator: Farahani, Meysam, Tang, Youneng, Locke, Bruce R., Clark, Clayton J., Florida State University, FAMU-FSU College of Engineering, Department of Civil and Environmental Engineering
Abstract/Description: Perfluorooctanoic acid (PFOA) is persistent in environment due to its stable structure. It is also toxic to animals and human. The objective of this research is to remove PFOA with a non-thermal plasma reactor, anaerobic and aerobic bio-reactors, and their combination. Mineralization and defluorination (i.e., fluoride production) occurred in the plasma reactor. Neither PFOA removal nor fluoride production was observed in the bioreactors. In the plasma reactor with Argon as the carrier gas, 20...
Show morePerfluorooctanoic acid (PFOA) is persistent in environment due to its stable structure. It is also toxic to animals and human. The objective of this research is to remove PFOA with a non-thermal plasma reactor, anaerobic and aerobic bio-reactors, and their combination. Mineralization and defluorination (i.e., fluoride production) occurred in the plasma reactor. Neither PFOA removal nor fluoride production was observed in the bioreactors. In the plasma reactor with Argon as the carrier gas, 20 µM of PFOA in deionized (DI) water was removed to 4.22 and 4.04 µM, respectively, when the hydraulic retention time (HRT) was 0.21 s and 0.15 s, respectively. When the carrier gas was changed to Helium, PFOA was removed to 3.85 µM and 3.77 µM, respectively. Therefore, the carrier gas and HRT did not have significant effect on PFOA degradation. However, the carrier gas and HRT strongly affected the defluorination rate: 11% (for HRT = 0.21 s) and 6.5% (for HRT = 0.15) when Argon was the carrier gas, and 22% (for HRT = 0.21 s) and 8.6% (for HRT = 0.15 s) when Helium was the carrier gas. Consequently, a higher energy yield was achieved with Helium as the carrier gas (maximum of 11.3×10-11 mole F- production/J) than with Argon as the carrier gas (maximum of 6.43×10-11 mole F- production/J). Perfluoroheptanoic acid (PFHpA) and perfluorohexanoic acid (PFHxA) were observed in the effluent of the non-thermal plasma reactor by using liquid chromatography-tandem mass spectrometry (LC/MS/MS). The intermediates production rate was higher when argon was the carrier gas compared with Helium, probably because the degradation mechanisms are different for PFOA and their intermediates.
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Date Issued: 2019
Identifier: 2019_Spring_Farahani_fsu_0071N_15034
Format: Thesis

Title: Enhancement of Nitrogen Use Efficiency and Mitigation of Nitrous Oxide Emission in Agricultural Fields.
Creator: Li, Simeng, Chen, Gang, Sang, Qing-Xiang, Clark, Clayton J., Tang, Youneng, Florida State University, FAMU-FSU College of Engineering (Tallahassee, Fla.), Department of Civil...
Show moreLi, Simeng, Chen, Gang, Sang, Qing-Xiang, Clark, Clayton J., Tang, Youneng, Florida State University, FAMU-FSU College of Engineering (Tallahassee, Fla.), Department of Civil and Environmental Engineering
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Abstract/Description: Recent intensification of agriculture in face of the continuously increasing food demand has caused many environmental and socioeconomic problems. Excessive use of nitrogen (N) fertilizers is prevalent on many farms today. However, a large proportion of the N applied to agricultural soil contributes very little to crop production. Instead, a considerable amount of N is lost via leaching into groundwater, via runoff into surface water, and via nitrous oxide (N2O) emission into the atmosphere....
Show moreRecent intensification of agriculture in face of the continuously increasing food demand has caused many environmental and socioeconomic problems. Excessive use of nitrogen (N) fertilizers is prevalent on many farms today. However, a large proportion of the N applied to agricultural soil contributes very little to crop production. Instead, a considerable amount of N is lost via leaching into groundwater, via runoff into surface water, and via nitrous oxide (N2O) emission into the atmosphere. As a result, the ecosystem is negatively impacted. Sustainable N management should aim at supplying sufficient N for optimum crop growth and development, while keeping losses to the environment to a minimum. Towards this goal, it is essential to enhance N retention and at the same time mitigate N2O emission in agricultural soil. Being the leader of one USDA project, I investigated the effects of different N management approaches that are based on the use of biochar, dicyandiamide (nitrification inhibitor) and polyacrylamide (superabsorbent hydrogel) in agricultural soils. It was found that a significantly higher amount of ammonium (NH4+) could be retained in the biochar-amended soil, comparing to the control soil. However, the retention of other ionic forms of N, such as nitrite (NO2-) and nitrate (NO3-), was barely improved. In fertilized soil, nitrification is a common process that transforms NH4+ into NO2- and eventually NO3-. To limit this transformation, the effects of one of the most commonly used nitrification inhibitor, i.e., dicyandiamide (DCD), was studied in combination with biochar. Based on the experimental data, mathematical models were developed to estimate the rate of nitrification impacted by the inhibition of persistently degrading DCD. It was discovered that the presence of biochar accelerated the biodegradation of both DCD and NH4+, but effectively reduced the spatial separation between the two. Depending on the soil properties and environmental conditions, the combined use of DCD and biochar can have versatile effects on nitrification inhibition. Also, considering the great amount of field data reported in the literature, statistical methods such as data synthesis and meta-analysis were also exploited to excavate the insightful information on the effectiveness of different soil amendments (e.g., biochar) in terms of N retention, crop production and N2O emission. Lastly, the recalcitrance of biochar, which is directly related to biochar's soil carbon sequestration potential, was also discussed. In order to quantify and compare the soil carbon sequestration potential of biochar produced from different conditions and feedstock types, a carbon-based recalcitrance index was developed using a state-of-the-art thermochemical technique.
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Date Issued: 2019
Identifier: 2019_Summer_Li_fsu_0071E_15255
Format: Thesis

Title: Quantification of Methane Emissions via the Use of an Optical Remote Sensing Technique in a Landfill Setting.
Creator: Clark, Jeremy Matthew, Abichou, Tarek, Chanton, Jeff, Watts, Michael, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: The United States Environmental Protection Agency (USEPA) has proposed a method that will be used to quantify fugitive emissions from large area sources such as landfills. The method is presented in the USEPA's Other Test Method-10 (OTM-10) manual. The method utilizes non-intersecting multiple-beam paths, scanning equipment, and Optical Remote Sensing (ORS) instruments in a variety of radial configurations. The use of an ORS instrument to scan in a radial configuration introduces radial plume...
Show moreThe United States Environmental Protection Agency (USEPA) has proposed a method that will be used to quantify fugitive emissions from large area sources such as landfills. The method is presented in the USEPA's Other Test Method-10 (OTM-10) manual. The method utilizes non-intersecting multiple-beam paths, scanning equipment, and Optical Remote Sensing (ORS) instruments in a variety of radial configurations. The use of an ORS instrument to scan in a radial configuration introduces radial plume mapping (RPM) to the OTM-10. There are several RPM methods discussed in the OTM-10, such as horizontal radial plume mapping (HRPM), vertical radial plume mapping (VRPM), and 1-D radial plume mapping (1D-RPM). The VRPM is the only method discussed in the OTM-10 that is capable computing pollutant flow rates for a large area source such as a landfill, so this study looks into the reliability of the VRPM's ability to quantify methane emissions from a landfill setting. The VRPM is used as a tool to quantify pollutant concentrations measured in the vertical plane downwind from the emissions source. In conjunction with the concentration data, which is computed by the vertical plane, wind speed and direction data is monitored to convert pollutant concentration values to pollutant flow rates by multiplying the concentration data to a trigonometric function of the wind speed. The objective of this study was to investigate uncertainties associated with the use of the VRPM method in a landfill setting. Once deficiencies in the method are found, users of the VRPM in a landfill setting will be provided with accurate guidelines on the reliability of the method under a variety of conditions. Several uncertainties associated with the VRPM method in a landfill setting include; the location of hot spots in comparison to vertical plane location, the reliability of the of the optimization algorithm used in quantification to correctly compute emission concentration when multiple hot spots are present, and the area contributing to flux (ACF). Through this study it was found that the spatial variability of emissions in the emitting domain can lead to uncertainties of -34 to 190% in the measured flux value when idealistic scenarios were simulated. The level of uncertainty can be reduced by improving the vertical planes location in comparison to the hot spots. The variability in wind direction during VRPM testing can introduce an uncertainty of 20% of the measured flux value. This study also provides an estimate to the ACF for each meteorological stability class defined in the field and has an uncertainty of 10 to 30% associated with it.
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Date Issued: 2010
Identifier: FSU_migr_etd-3592
Format: Thesis

Title: Finite Element Analysis on the Effect of Fire for Specified Duration, on a Reinforced Concrete Beam with Varied Boundary Conditions.
Creator: Chythanya, Meghana, Spainhour, Lisa K., Rambo-Roddenberry, Michelle, Jung, Sungmoon, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: Concrete is a poor conductor of heat due to its incombustible nature and low thermal diffusivity, which guarantee a slow propagation of thermal transients within the structural members. Despite exhibiting a good behavior at high temperatures, it can suffer considerable damage when exposed to fire. The knowledge of high-temperature properties of concrete is critical for fire resistance assessment because the fire performance of structural members like beams depends on the properties of the...
Show moreConcrete is a poor conductor of heat due to its incombustible nature and low thermal diffusivity, which guarantee a slow propagation of thermal transients within the structural members. Despite exhibiting a good behavior at high temperatures, it can suffer considerable damage when exposed to fire. The knowledge of high-temperature properties of concrete is critical for fire resistance assessment because the fire performance of structural members like beams depends on the properties of the constituent materials. To predict the conditions within the RC beams subjected to fire, knowledge is required of the behavior of concrete subjected to high temperatures. To ensure the safety of RC structural systems in the event of fire, concrete members should be designed against fire. The temperature dependent properties that are important for establishing an understanding of the fire-response of RC structures include thermal and material properties at elevated temperatures. In this research, a finite element model was developed using ALGOR® to study the impact of fire on an RC beams. This model provides information about temperature distributions in the beam for given initial and boundary conditions. Using finite element analysis, the entire beam was meshed into small segments called elements. The elements hold information about the physical properties of their corresponding materials. Each element was bounded by nodal points. Boundary conditions were included on the appropriate nodes in the model. The different boundary conditions on which the analysis was conducted are pin-roller, pin-pin, fixed on both ends and cantilever. All the results obtained from the analyses are time dependent, including displacement, stresses and strains. The location and magnitude of maximum stress, strain and displacement for each boundary condition were determined with the analysis. The maximum principal stress in each case when compared to the compressive strength of normal strength concrete, implied that failure has occurred in all the four cases i.e. pin-roller, pin-pin, fixed on both ends and cantilever. The results obtained from the Transient Heat Analysis were compared with the temperature distribution from other studies. It was found that the temperature distribution determined in Kodur et al is very similar to the temperature distribution which results from the transient heat transfer analysis.
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Date Issued: 2009
Identifier: FSU_migr_etd-3609
Format: Thesis

Title: Relationships of Geomorphic Conditions and Woody Materials in Coastal Plain Streams.
Creator: Morris, Cameron, Hilton, Amy Chan, Clark, Clayton, Watts, Michael, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: Streams of the coastal plain were inventoried and surveyed for large woody material (LWM) in relationship with fluvial geomorphic characteristics. This empirical data was used to identify wood density based on stream channel hydraulic geometry (i.e., width, depth, and cross sectional area) and the relationship to bankfull discharge and watershed area. Drainage area and stream bankfull width were determined to be correlated with total volume and number of pieces of LWM, providing predictive...
Show moreStreams of the coastal plain were inventoried and surveyed for large woody material (LWM) in relationship with fluvial geomorphic characteristics. This empirical data was used to identify wood density based on stream channel hydraulic geometry (i.e., width, depth, and cross sectional area) and the relationship to bankfull discharge and watershed area. Drainage area and stream bankfull width were determined to be correlated with total volume and number of pieces of LWM, providing predictive capability for the natural abundance of LWM in streams of the coastal plain. Following its restoration, Anderson Branch was inventoried for in-stream LWM and monitored for stability. Minimal variability observed in the dimension, pattern, and profile of the stream channel was attributed to the proper placement and density of LWM. Streams of the coastal plain were also surveyed for the contribution of sandbed formations and woody material to channel roughness. The protrusion height of sandbed formations and woody material were determined to be a better estimate of Manning's n than bed material size, providing improved guidance in restoration practices as well as a more accurate method of predicting bankfull discharge in the event a gage/and or regional curve is unavailable.
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Date Issued: 2012
Identifier: FSU_migr_etd-5411
Format: Thesis

Title: An Assessement of on-Site Renewable Energy Source Consideration with Original Building Construction Procurement Efforts.
Creator: Sneed, Troy Lenard, Clark, Clayton J., AbdelRazig, Yassir, Sobanjo, John, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: As energy resources are needed in abundance to sustain the ever evolving global economy, the world's energy dependency for good reason, is beginning to shift. Various studies have shown that although fossil fuels are still the primary source of energy for the world, the utilization of more sustainable energy resources is on the rise. However due to current competitive bidding strategies and underlying practices that typically consider sustainable features such as renewable energy sources as...
Show moreAs energy resources are needed in abundance to sustain the ever evolving global economy, the world's energy dependency for good reason, is beginning to shift. Various studies have shown that although fossil fuels are still the primary source of energy for the world, the utilization of more sustainable energy resources is on the rise. However due to current competitive bidding strategies and underlying practices that typically consider sustainable features such as renewable energy sources as costly additions rather than effective options to program requirements, building construction procurement strategies have been slow to embrace this change. In this thesis, a methodology is derived for assessing the overall benefits of utilizing a renewable energy source as a program option from the original building construction procurement effort. This methodology was developed by utilizing project procurement methods and techniques, in addition to certain life cycle costing concepts. Data from the original procurement of The Basic School in Quantico, Virginia was used to apply this methodology. The results of this application and supplemental research show that the incorporation of a renewable energy source into the original building construction procurement effort as opposed to additions that are incorporated later in the project procurement effort produced cost and schedule benefits. Furthermore, a contractor could apply this methodology to similar projects that incorporate sustainable features into its original design and cost estimates, and utilize the findings of the application in the technical components of future projects.
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Date Issued: 2012
Identifier: FSU_migr_etd-5437
Format: Thesis

$Ozone Pre-Treatment to Enhance Anaerobic Degradation of Refractory Landfill Leachate Organics$

Title: Ozone Pre-Treatment to Enhance Anaerobic Degradation of Refractory Landfill Leachate Organics.
Creator: Qiao, Yu, Watts, Michael, Chen, Gang, Hilton, Amy Chan, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: Advanced oxidation processes (AOPs) have garnered recent consideration as an option to reduce organic loading, and the recalcitrance of mature landfill leachate. Hydroxyl radicals (*OH) are produced during AOPs, which are effective in destroying organic chemicals. To investigate the potential for leachate conditioning by pre-ozonation treatment (O3/H2O2 and O3), low-mg/L level ozone stock solutions were spiked into an `old' landfill leachate (0 to 7.5mg/L O3). The stoichiometric ratio of 1.1...
Show moreAdvanced oxidation processes (AOPs) have garnered recent consideration as an option to reduce organic loading, and the recalcitrance of mature landfill leachate. Hydroxyl radicals (*OH) are produced during AOPs, which are effective in destroying organic chemicals. To investigate the potential for leachate conditioning by pre-ozonation treatment (O3/H2O2 and O3), low-mg/L level ozone stock solutions were spiked into an `old' landfill leachate (0 to 7.5mg/L O3). The stoichiometric ratio of 1.1:1 was determined to be the optimal molar ratio of O3 to H2O2 based on the biodegradability of the leachate organics. The leachate conditioning includes: measurement of the three anthropogenic contaminants tris-(2-chloroethyl) phosphate (TCEP), tris-(butoxyethyl)-phosphate (TBEP) and 17ß-estradiol (E2) by pre-ozonation treatment and the pre-ozonation followed by anaerobic treatment; COD and BOD5/COD analysis of the ozonated leachate; measurement of the methane and total gas formation during the anaerobic incubation; also the COD analysis of the mixed leachate and sludge solution during the anaerobic incubation. When treating with O3 and O3/H2O2 pre-oxidation, the removal of E2 was 65% at the ozone dose of 4.5mg/L to 5.4mg/L, which was higher than that of TCEP and TBEP. Based on one-way ANOVA analysis, the O3/H2O2 pre-treatment was observed to have significantly improved degradation of E2 during anaerobic incubation of oxidized leachates (removal rate of E2 was 53.7% after 15 days of incubation). However, O3 pre-treatment improved post-ozone degradation of TCEP and TBEP by 26% and 39.3% as compared with O3/H2O2 after 15 days of incubation. In addition, overall anaerobic activity was not impacted by the applied ozone pre-treatments, as measured by methane formation, total gas formation, and COD removal. In general, low-mg/L ozone pre-treatment, prior to anaerobic incubation, was found to improve biological degradation
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Date Issued: 2012
Identifier: FSU_migr_etd-5421
Format: Thesis

Title: Analysis of Cost Change in Air Force Construction Projects from Planning to Completion.
Creator: Barnes, Robert J., Sobanjo, John O., Abdelrazig, Yassir, Spainhour, Lisa, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: Construction is a major industry in the United States. In 2010, over $506 billion was spent in construction and construction-related activity, amounting to over 3.4% of Gross Domestic Product (GDP). $21.2 billion, or 0.6% of federal outlays for 2010 was spent on military construction. This accounts for nearly 4% of total construction annually. This study examined three variables in the life of an Air Force military construction (MILCON) project: the programmed amount (PA), the contract award ...
Show moreConstruction is a major industry in the United States. In 2010, over $506 billion was spent in construction and construction-related activity, amounting to over 3.4% of Gross Domestic Product (GDP). $21.2 billion, or 0.6% of federal outlays for 2010 was spent on military construction. This accounts for nearly 4% of total construction annually. This study examined three variables in the life of an Air Force military construction (MILCON) project: the programmed amount (PA), the contract award (CA), and the final current working estimate (CWE). These variables, respectively, reflect the initial planning budget (PA), the actual contractor's estimate and bid (CA), and the final, actual cost of the project to the Air Force (CWE). Statistical hypothesis tests showed there is an appreciable difference between each variable. Generally speaking, the PA is higher than the CA, but the CWE approaches the PA at end of the project. The study suggests several reasons for this, including contractor estimate errors or "bad faith", non-inclusion of inflation, and initial estimate inaccuracy. The results of this study can be used to better analyze contractors' bids as well as initial budgetary estimates to get a more accurate picture of the cost of a particular MILCON project.
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Date Issued: 2012
Identifier: FSU_migr_etd-5317
Format: Thesis

Title: Correlation of Water Quality Indicators for Coastal Marshes.
Creator: Hendrix, Matthew, Chen, Gang, Watts, Michael, Clark, Clayton, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: Florida provides some of the most diverse and beautiful environments in the United States, with northwest Florida being a nearly undisturbed bounty of lush lands, springs, and other geological and ecological features. Increases in population have recently started to jeopardize some of Florida's prized areas, including the Ochlocknee-St Marks Basins. Development and agriculture has started to affect watersheds and waterbodies. This study has evaluated the water quality of coastal marshes at...
Show moreFlorida provides some of the most diverse and beautiful environments in the United States, with northwest Florida being a nearly undisturbed bounty of lush lands, springs, and other geological and ecological features. Increases in population have recently started to jeopardize some of Florida's prized areas, including the Ochlocknee-St Marks Basins. Development and agriculture has started to affect watersheds and waterbodies. This study has evaluated the water quality of coastal marshes at the St. Marks national Wildlife Refuge in terms of coliform and chlorophyll a. With these constituents, dissolved oxygen (DO), temperature, pH, conductivity, and total suspended solids were evaluated. The study took place with data from January 2009 to June 2009. The study site of this research, St. Marks National Wildlife Refuge, is located 25 miles south of Tallahassee along the Gulf Coast of Florida. To analyze for coliform, 100ml samples were filtered on cellulose nitrate membranes and subsequently incubated. After 24hrs the fecal coli forms were counted and recorded. Measuring the chlorophyll a was done taking a volume of water from a particular depth and filtering it through a fine glass fiber filter to collect all of the particulate material great than 1 micron. To extract the chlorophyll, acetone/alcohol was used as a solvent and then measured using an optical kit and Luminometer utilizing a chlorophyll a standard. Effective diffusion was then measured in the lab using a diffusion coefficient in distilled water. This process was also observed using a Hamamatsu high sensitivity monochrome digital camera in a dark room, with the sample being placed in a petri dish with native soil. Chlorophyll a adsorption was measured by introducing the sample to a column filled with goethite-coated silica sand. Transport parameters were obtained by fitting the experimentally obtained Chlorophyll a breakthrough data using an implicit, finite-difference scheme. All the parameters were optimized by minimizing the sum of squared differences between observed and fitted concentrations using the nonlinear least-square method. Some key observations over the sample period include the dropping of DO as the summer months began indicating increased microbial activity with temperature. TKN and Chlorophyll were observed to increase as temperature increased. When observing Chlorophyll as a function of TKN, the Pearson Correlation and the plot indicate that with increased TKN more microbiological activity occurs - such as with plants, algae, etc. Interestingly when Chlorophyll was plotted as a function of DO, the low DO encourages microbial growth, however only to an extent. The point can be made that less polluted water has less microbial activity. The correlation between coliform and turbidity showed an increase of coliform with NTU. Chlorophyll as a function of turbidity showed no correlation. However as a first order function, d[Chlorophyll a]/d[Turbidity] displayed a linear relationship with turbidity, indicating the correlation of chlorophyll a variation with respect to turbidity. When conductivity was plotted against pH, the variability of conductivity and pH was not significantly different. Chlorophyll a also had a correlation with pH. With the increase of pH, chlorophyll a exponentially decreased. This research shows the increased ability to forecast and assess risk presented by development and agriculture of coastal environment based on physical and chemical variations in coastal wetland ecosystems.
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Date Issued: 2012
Identifier: FSU_migr_etd-5361
Format: Thesis

Title: A Physiologically Based Toxicokinetic (PBTK) Model for Inhalation Exposure to Benzene and Its Engineering Applications.
Creator: Kulkarni, Tara Aniket, Dzurik, Andrew, Arora, Krishna, Kolta, Malak, Leszczynska, Danuta, Hilton, Amy Chan, Department of Civil and Environmental Engineering, Florida State...
Show moreKulkarni, Tara Aniket, Dzurik, Andrew, Arora, Krishna, Kolta, Malak, Leszczynska, Danuta, Hilton, Amy Chan, Department of Civil and Environmental Engineering, Florida State University
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Abstract/Description: Physiologically Based Parmacokinetic/Toxicokinetic (PBPK/TK) Models are commonly used in the pharmaceutical and toxicological sciences to understand the fate and disposition of drugs in the human body. However, they are not being applied in environmental engineering studies involving risk, except in some health risk assessment studies. The risk posed by the adverse effects of a xenobiotic on the human body can be quantified using PBPK/TK models and such numbers can be used in engineering...
Show morePhysiologically Based Parmacokinetic/Toxicokinetic (PBPK/TK) Models are commonly used in the pharmaceutical and toxicological sciences to understand the fate and disposition of drugs in the human body. However, they are not being applied in environmental engineering studies involving risk, except in some health risk assessment studies. The risk posed by the adverse effects of a xenobiotic on the human body can be quantified using PBPK/TK models and such numbers can be used in engineering situations such as determining clean up levels at remediation sites, locating hazardous waste facilities and installing pollution control and monitoring devices. Thus the PBPK/TK modeling can serve as an appropriate tool in global initiatives such as Risk Based Corrective Action (RBCA). This study presents two areas of new and contributory research. The first is a toxicological model for benzene and its major metabolites considering different doses and forms (continuous and intermittent) of inhalation exposure in male and female subjects of the human population. This model considers the bone marrow as a separate compartment and uses an extended version of the Michaelis- Menten kinetics for enzymes, both areas of study, not strongly addressed before. The results of this part of the study reveal that PBPK/TK models can successfully simulate intermittent exposures, which had not been done before. The benzene concentration levels are not significantly different in male and female exposures. The addition of the bone marrow as a separate compartment is recommended in all benzene models. The sensitivity analysis based on the Monte Carlo technique indicate that most of the rate constants tested, that are involved in the metabolic processes are stable; 2 are highly sensitive. The partition coefficient of benzene for the fat compartment is somewhat stable, but the model probably over-predicts the benzene concentrations in the fat compartment. The second part of the study is to determine the possible use of PBPK/TK models in environmental engineering studies. Verbal communication from personnel of the Florida Department of Environmental Protection encouraged the theory that the model developed in this study can be potentially used in RBCA aspects of environmental engineering. So, an environmental engineering case study was presented to demonstrate its use as a screening tool at a petroleum contaminated site. Benzene concentration levels are estimated in male workers, at the site working on a remediation project for 3 months and getting exposed to 8 hours/day, 5days/week of continuous benzene exposure. An example on the potential use of the model in air pollution engineering problems is also presented. The results from this portion of the study as well as personal communication with FDEP personnel indicate that the PBPK/TK model developed in this study will benefit environmental engineering studies.
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Date Issued: 2004
Identifier: FSU_migr_etd-2971
Format: Thesis

Title: Comparison of Fatal Traffic Crashes in Southern and Northern Regions of the State of Florida a Study of Fatal Traffic Crashes in Florida from 1998-2000.
Creator: Kadabagere, Nirup H., Spainhour, Lisa K., Mtenga, Primus V., Sobanjo, John O., Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: The highway fatality rate in the state of Florida is very high, with 40 percent more facilities per vehicle mile than the national average in 1999. Crashes involving trucks are fatal more than crashes involving passenger cars. The State Safety Office of the Florida Department of Transportation proposed conducting a review and analysis of traffic fatalities and truck crashes on the state roads of Florida to tackle these problems. The goal of this project was to go beyond the data currently...
Show moreThe highway fatality rate in the state of Florida is very high, with 40 percent more facilities per vehicle mile than the national average in 1999. Crashes involving trucks are fatal more than crashes involving passenger cars. The State Safety Office of the Florida Department of Transportation proposed conducting a review and analysis of traffic fatalities and truck crashes on the state roads of Florida to tackle these problems. The goal of this project was to go beyond the data currently available from the Florida traffic crash report (FTCR) and homicide reports to create a comprehensive database of contributing causes of fatal crashes. The outcome of the study identified engineering and behavioral issues. The results will be used to guide future design standards as well as to develop education and enforcement programs. The objective of the research was to provide the analysis of the causes of fatal traffic crashes and traffic fatalities. The major tasks were: 1. Identifying data elements deemed to be potential contributors for fatal crashes. 2. Investigating all fatal crashes in the year 2000 for the study regions and fatal crashes involving trucks for the year 1998 and 1999 in the study regions. 3. For each crash, identifying factors contributing to both the crash and the fatalities. 4. Developing a computerized database and querying tool. This report contains the results of a component of the statewide study. The primary purpose of the study was to compare the nature of crashes in two different regions. One region in northern Florida consisted of six counties; Suwannee, Madison, Gilchrist, Hamilton, Lafayette and Alachua counties in FDOT District 2; the second region was southern, consisting of Miami-Dade County in FDOT District 6. The southern region is primarily urban, with over 26 million daily vehicle miles traveled, while the northern region is primarily rural, with fewer than 8 million daily vehicle miles travelled. Both regions have approximately 2500 lane miles. Parameters considered included driver behavior, roadway characteristics and other factors, contributing to both crashes and fatalities. It was concluded that the primary contributing factor in the majority of the fatal crashes was human error, including driver errors in negotiating intersections and pedestrians violating the right of way of the vehicle. Driver defects, vehicle defects, and weather were not found to be common in the crashes in both the regions. Crashes occurred most frequently at intersections in both the regions. There was also significant number of run-off the road crashes in both the regions. Male drivers and young drivers were involved in fatal crashes most frequently. Most of the pedestrian crashes in the study occurred in the southern region. Intersection crashes in the southern region frequently involved left turn crashes, often where the driver misjudged the gap in the oncoming traffic. Rear-end crashes were found to be more common in the northern region. Overall, forty-four percent of pedestrians in the fatal were found to be under the influence of alcohol and drugs. In the southern region, approximately one in every four at-fault drivers were under the influence of alcohol and drugs. Influence of alcohol and drugs was less common in the northern region found to be common. Twenty-six percent of at-fault drivers in the northern region were below age 21, compared with less than 8 percent in the southern region. On the other hand, 58 percent of the 51-60 year old drivers in the southern region were found at-fault, compared with only 24 percent in the northern region. Eighty-six percent of the at-fault drivers were from the county of the crash in the southern region whereas only 34 percent of at-fault drivers in northern region were from the county of the crash. Heavy truck crashes are overrepresented in northern region: the most common type of crashes involving trucks were rear-end crashes. A total of sixty percent and forty-seven percent of occupants in the fatal crashes were using seat belts or child restraints in the southern and northern regions respectively. Wearing seat belts reduced the likelihood of dying in the crash from 73 percent to 45 percent
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Date Issued: 2003
Identifier: FSU_migr_etd-3394
Format: Thesis

Title: Engineering Properties of Florida Concrete Mixes for Implementing the Aashto Recommended Mechanistic Empirical Rigid Pavement Design Guide.
Creator: Kampmann, Raphael, Ping, Wei-Chou V., Rambo-Roddenberry, Michelle, Abichou, Tarek, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: The coefficient of thermal expansion (CTE) is a fundamental property of Portland cement concrete (PCC). The magnitude of temperature-related pavement deformations is directly proportional to the CTE during the pavement design life. Because of its critical effect on PCC performance, it is proposed to be considered for distress and smoothness prediction by the newly developed Mechanistic-Empirical Pavement Design Guide (M-E PDG). To account for M-E PDG implementation in Florida, three typical...
Show moreThe coefficient of thermal expansion (CTE) is a fundamental property of Portland cement concrete (PCC). The magnitude of temperature-related pavement deformations is directly proportional to the CTE during the pavement design life. Because of its critical effect on PCC performance, it is proposed to be considered for distress and smoothness prediction by the newly developed Mechanistic-Empirical Pavement Design Guide (M-E PDG). To account for M-E PDG implementation in Florida, three typical Florida concrete mixtures were experimentally measured for compressive strength, flexural strength, splitting tensile strength, Young's modulus, Poisson's ratio, and CTE according to AASHTO TP-60. The test results revealed that PCC's CTE rapidly increases within the first week but stabilizes after 28 days. However, to accurately analyze the mix designs using the new mechanistic-empirical concept considering all three hierarchy levels, nine different JPCP models were generated. Their PCC layer thicknesses were iteratively determined before the resultant pavement structures were evaluated based on the predicted distresses (faulting and cracking) and smoothness (IRI). It was found, that cracking is the most critical pavement performance criterion for Florida JPCP. Moreover, top-down fatigue damage was isolated to be the controlling failure mechanism because of insignificant faulting and minor smoothness reduction. Based on the thickness idealized JPCP models, a CTE sensitivity matrix was developed for adequate comparison of predicted pavement performance under interchanging CTE values. Despite wide ranging properties, clear patterns were exposed and distinctive performance envelopes arose for certain criteria. It was established that the new M-E PDG, is minimally CTE sensitive to faulting, CTE sensitive to bottom-up damage (for thin PCC layers), and extremely CTE sensitive to top-down damage, cracking, and smoothness.
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Date Issued: 2008
Identifier: FSU_migr_etd-3358
Format: Thesis

Title: Engineering Considerations for Privatizing Water and Wastewater Utility Systems.
Creator: Voight, Dana Evans, Hilton, Amy Chan, Watts, Michael J., Chen, Gang, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: Due to shrinking federal, state, and local utility budgets, city management structures requiring more cost effect utility operating models, and ever more stringent environmental regulations requiring technical expertise, engineers are now faced with adapting to, evaluating, and providing technical support for various forms of utilities privatization. Utilities privatization (UP) is a method to leverage engineering and monetary resources to operate utility systems in a more technical and cost...
Show moreDue to shrinking federal, state, and local utility budgets, city management structures requiring more cost effect utility operating models, and ever more stringent environmental regulations requiring technical expertise, engineers are now faced with adapting to, evaluating, and providing technical support for various forms of utilities privatization. Utilities privatization (UP) is a method to leverage engineering and monetary resources to operate utility systems in a more technical and cost effective manner. Much has been written to date about UP from a business, economic, and even political perspective. However, little literature and guidance exist from an engineering point of view. Engineers are not taught how to participate in UP scenarios through their classical training nor even through their professional engineering associations. In fact, at first glance, some think privatizing utility systems is merely a financial and contractual function with only secondary input and support from the engineering community. This perception is dangerous to the communities being served by these utility systems. It must be understood that the economics and contractual considerations of any UP analysis should be driven by the engineering requirements. If the engineering requirements are ill-defined or absent, any UP action could result in significant health and safety concerns, operational deficiencies, staggering unexpected additional costs, potential loss of water rights, etc. for the communities being served. Thus, it is important for the engineering community to understand their roles and responsibilities when faced with and participating in the various forms of UP. This project was undertaken to examine engineering considerations for privatizing water and wastewater systems to which there has been little to no technical literature and guidance provided. Furthermore, the purpose of this project is to advance the idea that the engineering community has a significant role in the UP process and to provide background and technical guidance so engineers can participate to the best interest of the communities being served. Guidance will be provided so the engineering community understands the various forms of UP, the engineer's role, and how to participate in the different phases of a UP analysis. Case studies will be evaluated to elaborate on the critical engineering aspects involved and the overall success or failure of the UP action. The environmental considerations associated with UP will also be researched with guidance to the engineering community provided. These include impacts to the RCRA mixed sewage exemption, potential impacts to water and reuse rights, and the environmental liabilities associated with UP. Furthermore, guidance will be provided so engineers understand their role in UP economic analyses and how to support the technical aspects of UP to ensure industry operating standards such as American Water Works Association (AWWA) are met. Finally, engineering lessons learned will be provided drawing upon my experiences, since 1999, supporting the Headquarters Air Force Civil Engineering Support Agency (HQ AFCESA) which was charted to evaluate the privatization of 152 water and wastewater systems.
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Date Issued: 2009
Identifier: FSU_migr_etd-4545
Format: Thesis

Title: Colloid and Surfactant Transport Modeling Through Agricultural Soil.
Creator: Patil, Sandip R. (Sandip Raman), Chen, Gang, Ordóñez, Juan Carlos, Clark, Clayton, Watts, Michael, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: National Water-Quality Assessment Program (NAWQA) was designed just after the U.S. Geological was established. The primary objective of the NAWQA was to understand the key processes controlling contaminant fate and transport into the Nation's water resources. In particular, wide use of pesticides and fertilizers in agricultural field can impact on the quality of surface and ground waters. Contaminants can be carried to the water bodies by several ways. In colloid-facilitated transport process...
Show moreNational Water-Quality Assessment Program (NAWQA) was designed just after the U.S. Geological was established. The primary objective of the NAWQA was to understand the key processes controlling contaminant fate and transport into the Nation's water resources. In particular, wide use of pesticides and fertilizers in agricultural field can impact on the quality of surface and ground waters. Contaminants can be carried to the water bodies by several ways. In colloid-facilitated transport process colloidal particles serves as a transport media for the contaminants. Colloid release from the agricultural soil under unsaturated conditions is controlled by the hydrodynamic force, capillary force and electrostatic force that is determined by the solution chemistry in terms of solution ionic strength and pH. In this research, colloid release from the agricultural soil was investigated using an intact soil column collected from an agricultural site in Gadsden County of Florida. Colloid release was monitored and the colloid release curve was simulated using an implicit, finite-difference scheme to obtain the colloid release coefficient. It was found that the hydrodynamic force and electrostatic force overcame the capillary force under the experimental conditions of this research and consequently, colloids were released. For the colloid release, solution chemistry played a key role by controlling the colloid repulsive electrostatic force within the pore system. Colloid release exponentially decreased with the increase of solution ionic strength and increased with the increase of solution pH. Colloid release was finally found to be correlated to the colloid repulsive electrostatic force within the pore system, i.e., the greater the repulsive electrostatic force, more colloids were released. In situ colloid mobilization and transport has been studied under both saturated and unsaturated conditions. In saturated conditions, the controlling parameters are solution ionic strength and pH. Colloid mobilization and transport have been modeled by the advection-dispersion equation with a first-order colloid release. The inverse version of these models can provide a platform to estimate transport parameters based on transport observations. In this research, we taken the advantages of existing contaminants transport models by fully utilizing them to investigate colloid interactions with the surrounding environment and provide parameter constraints for colloid transport modeling applications under saturated conditions. In natural systems, colloids present a potential health risk due to their propensity to associate with contaminants or in the case of certain biological colloids, inherent pathogenic nature. Although colloidal interactions have been studied for many years and much has been learned about the physical and chemical processes that control colloid retention, there still remains significant uncertainty about the processes that govern colloid release. The aim of this study was to investigate the release of in situ colloids as a function of soil depth. Colloid release from intact agricultural soil columns with variable length was investigated. Colloid release curves were simulated using an implicit, finite-difference scheme and colloid release rate coefficient was found to be an exponential function of the soil depth. The simulated results demonstrated that transport parameters were not consistent along the depth of the soil profile. Wetting agents wet hydrophobic soil by lowering the cohesive and/or adhesive surface tension, which allows the water to spread out more evenly and allows for better penetration into the hydrophobic soils. While enhancing water penetration, wetting agent applications may bring adverse impact on the soil and groundwater at the same time. The residual organic phase in the soil pores poses a long-term source of groundwater contamination. After use, residual wetting agents and their degradation products are discharged to groundwater or directly to surface waters, then dispersed into different environmental compartments. In order to assess their environmental risks, we need to understand the distribution, behavior, fate and biological effects of these surfactants in the environment. This research was designed to investigate the application of nonionic wetting agents in agricultural soils. Performance of nonionic surfactants in intact soil columns collected from agricultural soils was explored and related to the soil and wetting agent properties. In addition, the impact of the organic concentration of wetting agent fate and transport was investigated. The transport of wetting agents in the agricultural soil columns was simulated using the proposed transport models and subsequently, the effect of organic compounds on wetting agent transport was quantified.
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Date Issued: 2012
Identifier: FSU_migr_etd-5098
Format: Thesis

Title: Risk Assessment of Florida's Coastal Bridges Exposed to Hurricane-Induced Storm Surge Wave Forces.
Creator: Stanford, Scott Steven, Sobanjo, John, Rambo-Roddenberry, Michelle, Spainhour, Lisa, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: The purpose and focus of this research was on studying the hazard to Florida's coastal bridges from storm surge induced wave forces inflicted on the bridges during hurricanes. It has been observed in recent years that bridges located in the coastal environment are vulnerable to deck unseating during the applied loading of storm surge wave forces. The goal of the research is to use modern and up-to-date analysis methods to address the risk and vulnerability of coastal bridges to being damaged...
Show moreThe purpose and focus of this research was on studying the hazard to Florida's coastal bridges from storm surge induced wave forces inflicted on the bridges during hurricanes. It has been observed in recent years that bridges located in the coastal environment are vulnerable to deck unseating during the applied loading of storm surge wave forces. The goal of the research is to use modern and up-to-date analysis methods to address the risk and vulnerability of coastal bridges to being damaged from storm surges during hurricanes along Florida's coastline. Implementing the current analysis methods will be useful for determining the magnitude of wave parameters and coinciding wave forces imposed on structural elements of a bridge superstructure. It is also the intention of this manuscript to address the need for an analysis of the entire network of Florida's coastal bridges, not just one specific bridge case study. This has been regarded as one of the largest limitations of current analysis in this field of work. This research provides an improved understanding of addressing bridge vulnerability from hurricane hazards on both local and network level as well as providing further insight into preventing and limiting the amount of damage that can occur during the event of a major hurricane making landfall.
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Date Issued: 2012
Identifier: FSU_migr_etd-5200
Format: Thesis

Title: Prefabricated Bridge Elements and Systems for off-System Bridges.
Creator: Servos, Joseph, Roddenberry, Michelle, Sobanjo, John, Spainhour, Lisa, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: The Federal Highway Administration's (FHWA) ``Every Day Counts'' initiative aims to shorten the overall project delivery time, enhance safety, and protect the environment both on and around construction projects. Using innovative planning, design, and construction methods, Accelerated Bridge Construction (ABC) techniques reduce on-site construction time for new or replacement bridges. One aspect of ABC is Prefabricated Bridge Elements and Systems (PBES), where bridge components are fabricated...
Show moreThe Federal Highway Administration's (FHWA) ``Every Day Counts'' initiative aims to shorten the overall project delivery time, enhance safety, and protect the environment both on and around construction projects. Using innovative planning, design, and construction methods, Accelerated Bridge Construction (ABC) techniques reduce on-site construction time for new or replacement bridges. One aspect of ABC is Prefabricated Bridge Elements and Systems (PBES), where bridge components are fabricated offsite to reduce on-site construction activities. Many state departments of transportation, including Florida DOT, are currently making efforts to implement PBES for their bridge construction projects. The purpose of this research project was to investigate other statesÕ standards and to evaluate them for possible implementation in Florida. An exhaustive search was made, and new literature was reviewed, to learn about current DOT standards and practices. The search revealed that the states with the most prefabricated bridge standards or activities are as follows: Utah, Alabama, Texas, Minnesota, and a collaboration of Northeastern states. These standards were reviewed for details such as the presence of post-tensioning, joint types, design load, and inspectability. The three standard bridge types that show the most promise for adoption by FDOT are: Florida DOT District 2Õs Truncated ``Florida I-Beam'' (FIB), MinnesotaÔs Inverted Tee Beam, and PCI's ``Northeastern Extreme Tee'' (NEXT) Beam. A summary of the findings, including advantages and disadvantages of the bridge systems, is included in this report. Also included is a comprehensive list of web links to standard drawings from all state DOTs, which could also be helpful to expedite other research that involves standards and bridge construction/design practices.
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Date Issued: 2012
Identifier: FSU_migr_etd-5173
Format: Thesis

Title: The Potential Reduction of Combined Endocrine Disrupting Compounds in Zero-Valent Iron.
Creator: Pipkin, Leslie M., Clark, Clayton, Chen, Gang, Watts, Michael, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: The research is focused on the degradation of two endocrine disrupting compounds (EDCs) in zero-valent iron. The endocrine disrupting compounds bisphenol A (BPA) and 17b-estradiol (E2) are chemical compounds that have an adverse effect on the environment, humans, and wildlife. These two chemical constituents are being examined in this research because they are still being used today and continue to impact their surrounding environment. These chemicals are considered persistent,...
Show moreThe research is focused on the degradation of two endocrine disrupting compounds (EDCs) in zero-valent iron. The endocrine disrupting compounds bisphenol A (BPA) and 17b-estradiol (E2) are chemical compounds that have an adverse effect on the environment, humans, and wildlife. These two chemical constituents are being examined in this research because they are still being used today and continue to impact their surrounding environment. These chemicals are considered persistent, bioaccumulative, and toxic to the environment. The research explores the technological use of zero-valent iron to degrade the chemical constituents in aqueous form. The study conducted laboratory batch experiments to compare the efficiency of using zero-valent iron in a reducing environment to remediate endocrine disrupting compounds in groundwater. The experimentations looked at varying ratios of volume of solution to mass of zero-valent iron. Furthermore, this study compared the reactions of the chemical constituent in question by varying the aqueous solution to entail the combined constituents (BPA and E2) to separate solutions to determine the chemical degradation model and rates over a period of a week. During the experiments held out with the combined concentration of BPA and E2, both BPA and E2 followed a power-law model. Degradation rates increased as the varying volume to mass ratio decreased. The higher degradation rates were found with a volume to mass solution at 2:1 which gave the chemicals the shortest half-lives. BPA's lowest calculated half-life was approximately 12 days. E2's lowest calculated half-life was approximately 1 day. The degradation rates varied for each EDC when the compounds were treated separately in an aqueous solution over a 24-hour period. The set of experimentations showed that the higher degradation rates occurred with a volume to mass ratio of 2:1. BPA followed the first-order degradation model and showed a reduction of approximately 93% with a calculated half-life of 24 days. E2 followed a pseudo first-order degradation model and showed a reduction of approximately 92% during a 24-hour period with a calculated half-life of 2.655 hours. The research shows that the chemicals are competing for the surface area of the iron when in combined solutions. The experimentations in separate solutions show that E2 is a limiting factor in the ZVI. The research determined that degradation of bisphenol A and 17b-estradiol will occur in an aqueous solution in zero-valent iron.
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Date Issued: 2012
Identifier: FSU_migr_etd-5112
Format: Thesis

Title: Numerical Simulations of Nutrient Removal by Slow-Rate Wastewater Irrigation and Conventional Septic Systems.
Creator: Harmon, Virginia P., Abichou, Tarek, Hilton, Amy Chan, Chen, Gang, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: Land application is one of the natural treatment processes for raw or partially treated domestic wastewater. Examples include application of septic tank effluent to soil for subsurface infiltration, slow-rate (SR) wastewater irrigation, overland flow wastewater application, and soil aquifer treatment (SAT), also called rapid infiltration (RI). These processes can remove nitrogen, which usually is the limiting design parameter for a land application system. Wastewater or septic tank effluent...
Show moreLand application is one of the natural treatment processes for raw or partially treated domestic wastewater. Examples include application of septic tank effluent to soil for subsurface infiltration, slow-rate (SR) wastewater irrigation, overland flow wastewater application, and soil aquifer treatment (SAT), also called rapid infiltration (RI). These processes can remove nitrogen, which usually is the limiting design parameter for a land application system. Wastewater or septic tank effluent applied to the land in this study contains organic nitrogen and ammonia, plus nitrate and nitrite in the wastewater. In this study, HYDRUS-1D software, version 3.0, was used to conduct numerical simulations of one-dimensional water flow and nitrogen transport in vertical profiles of unsaturated soil to simulate the following scenarios: 1) slow-rate wastewater irrigation and 2) the application of septic tank effluent to soil for subsurface infiltration. The total depth of each soil profile was 300 cm with one soil type (Kershaw Sand) in each profile. The slow-rate simulation profiles consisted only of soil; the septic simulation profiles contained a total of 270 cm of soil with a 30 cm space containing drainrock (no effect on simulation) around the effluent distribution pipe. It was assumed that all applied nitrogen was converted to nitrate within the same time period assumed for application, and that there was no adsorption of nitrate. Water balance outputs included cumulative transpiration, hydraulic flux across the bottom of the soil profile, evaporation, infiltration, and runoff per square centimeter of soil. Nitrogen balance outputs included cumulative amount of nitrate removed by denitrification, root nitrate uptake, and nitrogen flux across the bottom of the soil profile. In the slow-rate simulations 4.30 mg N per cm2 of soil surface was applied per year, and 96.0% of the applied nitrogen (4.13 mg per cm2) was removed by denitrification and root uptake. In the septic simulation, 50.5 mg N per cm2 of soil surface was applied per year for subsurface infiltration, and 63.6% of the applied nitrogen (32.1 mg/cm2) was removed by denitrification. The objective of this study was to compare the nutrient loading from two hypothetical nitrogen contributors to the environment analogous to, and with only a general resemblance to, 1) the City of Tallahassee Southeast Farm (SEF), which practices SR wastewater irrigation and 2) conventional septic systems. The modeling conditions for each contributor were set to be as similar as possible to those for the other contributor. Flux results from the above simulations (per square centimeter of soil during the second year of the simulation) were multiplied by appropriate factors to yield the total mass of nitrogen applied to the surfaces of and the total mass of nitrate exiting the bottoms of the 300-cm soil profiles for sources 1) and 2) during one year. The estimated total mass of nitrogen applied to the simulated Southeast Farm was 3.48 x 105 kg N/yr. The estimated total mass of nitrogen in the effluent from 28,217 septic tanks from conventional septic systems added to drainfields in the unconfined areas of Leon and Wakulla counties and in the semi-confined area of Leon County was 3.56 x 105 kg N/yr. The total mass of nitrogen as nitrate exiting the bottom of the soil profile of the simulated SEF (2,000 acres) was estimated to be 1.67 x 104 kg/yr. The total mass of nitrogen as nitrate exiting the bottoms of the soil profiles for the estimated 28,217 conventional septic systems in the geographical areas listed in the previous paragraph was estimated to be 1.31 x 105 kg/yr. Additional simulations of slow-rate wastewater irrigation were conducted to meet the objective of modeling the nitrogen removal while varying the wastewater loading rate and the denitrification rate constant (K). The inputs were chosen so that the nitrate concentration ranged from 0 to 1.6 mg/L N as nitrate in plots of simulated nitrate concentrations at the bottom of the soil profile versus wastewater loading rate. When K was 0.038/day, it was possible to maintain a nitrate concentration at the bottom of the soil profile at or below 1.0 mg/L as long as the daily hydraulic wastewater loading was less than or equal to 1.5 cm/day. The corresponding wastewater loading values for K of 0.025/day and K of 0.012/day were about 1.0 cm/day and 0.5 cm/day, respectively. The nitrate concentrations at bottom of soil profile corresponding to the current wastewater loading rate of 0.841 cm/d used for the simulated "Southeast Farm" were approximately 0.65 mg/L for K = 0.025/day and 0.15 mg/L for K = 0.038/day. The results of this study may be usable to compare the yearly amounts of nitrogen loading for the above facilities. However, the overall accuracy of the results in describing the real SEF or a real conventional septic system is low mainly because of the method of modeling denitrification, the simplified method of determining input values, and perhaps the complexity of the processes modeled. Future modeling could be conducted so as to improve upon the above limitations. Also, the simulation(s) could be set up to take into account the effect, if any, of the water table elevation on flow. Further studies are needed to better understand and predict denitrification, and other types of denitrification models are available. At real sites, soils with improved water-holding properties could be added via soil mixing, thus improving wastewater treatment performance.
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Date Issued: 2007
Identifier: FSU_migr_etd-4265
Format: Thesis

Title: Real-Time Construction Project Progress Tracking: A Hybrid Model for Wireless Technologies Selection, Assessment, and Implementation.
Creator: Ghanem, Amine, AbdelRazig, Yassir A., Brown, Jeffrey R., Sobanjo, John O., Ping, Wei-Chou V., Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: A construction project is considered as a process that involves many activities and a large amount of information of various types that are related to each other. Successful project management requires controlling all aspects of a construction project: quality and quantity of work, costs, and schedules to guarantee the success of the project. So the construction project control aims to effectively obtain real-time information of activities taking place on the site. Meanwhile, paper-based...
Show moreA construction project is considered as a process that involves many activities and a large amount of information of various types that are related to each other. Successful project management requires controlling all aspects of a construction project: quality and quantity of work, costs, and schedules to guarantee the success of the project. So the construction project control aims to effectively obtain real-time information of activities taking place on the site. Meanwhile, paper-based documents of project management used are becoming ineffective and can't get quick responses to the office and project control center. Integrating promising information technologies such as radio frequency identification (RFID), mobile computing devices, and wireless technology can be extremely useful for improving the effectiveness and convenience of information flow in construction projects. The probable benefits are potentially enormous, but the barriers associated with technology adoption within the construction industry, currently outweigh this potential. This research develops a control system for construction projects. The main objectives of this research include (1) developing a framework for real time construction project tracking; (2) applying such a system that integrates RFID technology with mobile computing and wireless technology to increase the efficiency of jobsite communication and data collection; (3) designing a database system for construction activities and updates, providing real-time information and wireless communication between offices and sites, subcontractors and suppliers; (4) developing a hybrid model for wireless technologies selection, assessment and implementation; (5) applying the model on pre-engineered steel construction projects and performing life cycle cost and cost benefit analysis. This model will greatly increase productivity and efficiency, will reduce labor hours and time required for tracking.
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Date Issued: 2007
Identifier: FSU_migr_etd-4339
Format: Thesis

Title: Correlation Between Falling Head and Double Ring Testing for a Full-Scale Infiltration Study.
Creator: Hayden, Audra H., Tawfiq, Kamal, Rambo-Roddenberry, Michelle, Ping, Wei-Chou V., Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: Stormwater management facility design is a branch of engineering that demands a full understanding of soil and permeability and how water infiltrates into the ground. With new residential and commercial developments, holding facilities for rainwater are required. Due to the cost associated with purchasing land for holding water, the idea is to make the pond dimensions as small as possible. With this idea, the engineer will need a precise way to determine the rate at which water will...
Show moreStormwater management facility design is a branch of engineering that demands a full understanding of soil and permeability and how water infiltrates into the ground. With new residential and commercial developments, holding facilities for rainwater are required. Due to the cost associated with purchasing land for holding water, the idea is to make the pond dimensions as small as possible. With this idea, the engineer will need a precise way to determine the rate at which water will infiltrate into the soil. This research centers on determining how permeability most accurately predicts a stormwater pond's actual infiltration rate. Several estimations for permeability have been evaluated: grain-size correlations, falling head permeameters, double ring infiltrometer tests and single ring infiltrometer tests. For this research, an existing stormwater facility was chosen. At this location, the field tests were conducted and subsurface samples were taken for laboratory analysis. In addition, to measure the actual field infiltration rate, a staff gage was installed and monitored after a precipitation event. The program MODRET was utilized to determine which of the various estimations of permeability yield an infiltration that most closely resembles that of monitored existing conditions.
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Date Issued: 2010
Identifier: FSU_migr_etd-4193
Format: Thesis

Title: Effects of Secondary Elements and Joints on Strain Distribution in Composite Steel Girder Bridges.
Creator: Lewis, Michael, Tawfiq, Kamal, Rambo-Roddenberry, Michelle, Jung, Sungmoon, Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: When considering the design of bridge girders, the American Association of State Highway and Transportation Officials (AASHTO) determine how the loads will be transferred to each girder. The equations used in AASHTO Load and Resistance Factor Design (LRFD) neglect the inertia added from secondary elements such as barriers and curbs. By neglecting these added effects, many bridges that are already built could have more strength than initially designed for. If the effects of these secondary...
Show moreWhen considering the design of bridge girders, the American Association of State Highway and Transportation Officials (AASHTO) determine how the loads will be transferred to each girder. The equations used in AASHTO Load and Resistance Factor Design (LRFD) neglect the inertia added from secondary elements such as barriers and curbs. By neglecting these added effects, many bridges that are already built could have more strength than initially designed for. If the effects of these secondary elements were considered, it would be possible to reduce the distribution factors that are given for interior and exterior girders. The bridge of concern for this project has four spans and was built in the early 1950s. Some repair work and modifications were conducted on the bridge and a load test was performed a week afterwards. The tests were done to find out if the repairs were adequate based on full composite action between the girders and the slab. During this initial test, some problems were discovered in one of the interior spans. This interior span is unique because it contains an expansion joint and a physical barrier and curb joint at the mid-span of the bridge. After problems were discovered, the physical joints were recommended to be grouted and a second load test was conducted afterwards. The second load test yielded much lower strains in the exterior girders due to the decrease in localized stress at the physical joint. In order to prove that filling the joint could improve the bridges strength, a finite element model was constructed to simulate this activity. Two models were made, one prior to filling the physical barrier and curb joints and one after. The test data was compared to the data from the finite element model to ensure accuracy. After the model was calibrated, the secondary members of the bridge were modified to study their effects. The primary goal of this research is to prove that a physical joint in a continuous exterior secondary element will cause the same amount of strain at its location as if they weren't there to begin with. By analyzing the finite element model data, it was found that when the joint is filled the behavior of the bridge changes and the exterior girder has up to 50% reduction in strain. The effect of concrete cracking and stress distribution that is associated with it is a secondary topic that was discussed because it was a driving factor in the model calibration.
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Date Issued: 2012
Identifier: FSU_migr_etd-4986
Format: Thesis

Title: Mitigation of Vortex-Induced Vibrations in Cables Using Macro-Fiber Composites.
Creator: Munoz, Gustavo J., Jung, Sungmoon, Rambo-Roddenberry, Michelle, Spainhour, Lisa K., Department of Civil and Environmental Engineering, Florida State University
Abstract/Description: Vortex-Induced Vibration (VIV) in cables is a prevalent phenomenon affecting the structural health of bridges and their components. Past studies have shown both passive and active methods are beneficial in the reduction of vibrations, however, a number of issues such as excessive base moment, transformation of geometry, intrusive implementation and fatigue limit the effectiveness of current engineering. A method involving no intrusion, no geometrical manipulation and a mechanism to prevent...
Show moreVortex-Induced Vibration (VIV) in cables is a prevalent phenomenon affecting the structural health of bridges and their components. Past studies have shown both passive and active methods are beneficial in the reduction of vibrations, however, a number of issues such as excessive base moment, transformation of geometry, intrusive implementation and fatigue limit the effectiveness of current engineering. A method involving no intrusion, no geometrical manipulation and a mechanism to prevent and mitigate VIV is needed. A "skin" of material embedded with Macro-Fiber Composite (MFC) material and with the capabilities of perturbing the surface near the separation point of vortex shedding is explored and tested. Simplifications of the proposed material are made in order to understand the effects of the capabilities of a perturbing skin of MFC material. Construction of a 17-ft Open-circuit wind tunnel is done in order to make the VIV condition to be tested with the near method of VIV control. The VIV on cables is recorded. Experiments are run inside the tunnel at a Re of 11400 and 6400. In order to see the effects of surface perturbations, an MFC actuation mechanism is made and a cable section effectively able to cause surface perturbations is built. A test is then run to find the effect of different angles of perturbation. Finally, a testing and analysis of a phase-difference of a signal, at prescribed perturbation frequencies is done. This is analyzed against surface vortex formation theory. The data are analyzed in order to see the capabilities of an MFC skin on VIV of cables. The mechanism shows promise in both reducing VIV and providing for a low-key, non-intrusive control mechanism.
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Date Issued: 2012
Identifier: FSU_migr_etd-5058
Format: Thesis

Theses and Dissertations (138)	+ -
Undergraduate Honors Theses (1)	+ -

Civil engineering (132)	+ -
Chemical engineering (3)	+ -
Engineering (3)	+ -

text (139)	+ -
doctoral thesis (6)	+ -
master thesis (4)	+ -

Florida State University (138)	+ -
Department of Civil and Environmental Engineering (137)	+ -
Chen, Gang (35)	+ -
Spainhour, Lisa (27)	+ -
Abichou, Tarek (24)	+ -

Sobanjo, John (24)	+ -
Hilton, Amy Chan (21)	+ -
Rambo-Roddenberry, Michelle (20)	+ -
Huang, Wenrui (19)	+ -
Tawfiq, Kamal (18)	+ -
Sobanjo, John O. (17)	+ -
Jung, Sungmoon (14)	+ -
AbdelRazig, Yassir (11)	+ -
Moses, Ren (11)	+ -
Spainhour, Lisa K. (11)	+ -
Tang, Youneng (11)	+ -
Clark, Clayton (10)	+ -
Wekezer, Jerry (10)	+ -
Mtenga, Primus (9)	+ -
Watts, Michael (9)	+ -
Clark, Clayton J. (8)	+ -
Mtenga, Primus V. (8)	+ -
Mussa, Renatus (8)	+ -
Ping, Wei-Chou V. (7)	+ -
Dzurik, Andrew (6)	+ -
FAMU-FSU College of Engineering (6)	+ -
Leszczynska, Danuta (6)	+ -
Tawfiq, Kamal S. (6)	+ -
Abdullah, Makola (5)	+ -
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