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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: Biomechanics of Older Drivers in Vehicular Crashes.
Creator: Fung, Kakit, Jung, Sungmoon, Zeng, Changchun (Chad), Sobanjo, John Olusegun, Tawfiq, Kamal Sulaiman, Florida State University, FAMU-FSU College of Engineering, Department of...
Show moreFung, Kakit, Jung, Sungmoon, Zeng, Changchun (Chad), Sobanjo, John Olusegun, Tawfiq, Kamal Sulaiman, Florida State University, FAMU-FSU College of Engineering, Department of Civil and Environmental Engineering
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Abstract/Description: The aging population is expected to increase substantially in the future. The fatal crash rates (per mile traveled) involving older drivers (65+) are considerably higher than those of younger drivers. This research involved conducting computational experiments involving dummy models to investigate the biomechanics of older drivers in vehicular crashes. Before conducting these experiments, the concepts of biological changes in older populations needed to be addressed. This allowed us to first...
Show moreThe aging population is expected to increase substantially in the future. The fatal crash rates (per mile traveled) involving older drivers (65+) are considerably higher than those of younger drivers. This research involved conducting computational experiments involving dummy models to investigate the biomechanics of older drivers in vehicular crashes. Before conducting these experiments, the concepts of biological changes in older populations needed to be addressed. This allowed us to first find out what makes the older drivers different from younger drivers. It was found that driving posture is one of the two key differences between the two age groups. The Hybrid III computational dummy model was used to investigate the effect of driving posture. The other key finding shows that older drivers are affected by aging factors such as material properties decrease and thickness decrease of bones. The Total Human Model for Safety (THUMS) was used because it can be modified to represent an aged driver to be used in the crash simulations. For the posture investigation, the idea is that driving posture for older drivers tend to be closer to the steering wheel whereas younger drivers are more laid back was incorporated. All computational work was completed in LS-DYNA; a finite element code used for non-linear impact analysis. The Finite Element (FE) simulation was validated by comparing the FE results with physical crash test results. These results were found in the Federal Motor Vehicle Safety Standards and Regulations (FMVSS) Report 208 for Frontal Crash Test. For subsequent simulations, posture changes based on the idea of aging according to literature review were implemented. For the Head Injury Criteria, the extended shoulders of an older driver yielded percent differences as high as 16%. The arms acted like braces to restrain the torso while the head continued forward. The extended knees also yielded a 16% increase in head injury. As for the chest acceleration, the extended hip and torso joints showed increased values. It was concluded that sitting closer was beneficial for the Head Injury Criteria but the opposite was true for the chest acceleration. The posture changes did not affect the pelvis acceleration. This investigation gave us a better understanding of what occurs in automobile accidents specific to older occupants. This knowledge can be useful in designing engineering approaches to mitigate injuries. Using the aged model, the material properties decrease yielded the highest chest deflection of 13.3%. For the bone thickness decrease, the chest acceleration showed the highest increase of 12.5%. The head acceleration and chest deflection showed noticeable increases. Overall with all three aging factors in place, the head and chest accelerations yielded high increases. Whereas for the deflection, it remains the same. The thoracic rotation increased the head resultant acceleration. The rotation decreased the deflection of the thorax because the ribs were more in line with the force imposed by the crash. It can withstand more force when the ribs are more parallel with the force. As for the chest acceleration, no significant change was present. It can be concluded that the older drivers in rear impacts experienced higher (Neck Injury Criterion) NICmax than younger drivers as much as 6.9% percent for the material property decrease and bone thickness decrease. The thorax rotation yielded a 4.7% decrease in NICmax. It is possible that this aging factor caused the thorax to conform more into the seatback thus reducing the injury. The bone thickness decreased affected the NICmax greatly whereas the material property decreased did show signs of minimal positive influence. The material property decreased yielded 0.8% increase while the thickness decreased yielded a 3.0% increase.
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Date Issued: 2017
Identifier: FSU_FALL2017_Fung_fsu_0071E_14227
Format: Thesis

Title: Effect of Friction on Vehicle Crashworthiness during Rollover.
Creator: Gleba, Michal, Jung, Sungmoon, Rambo-Roddenberry, Michelle Deanna, Spainhour, Lisa, Wekezer, Jerry W., Florida State University, College of Engineering, Department of Civil and...
Show moreGleba, Michal, Jung, Sungmoon, Rambo-Roddenberry, Michelle Deanna, Spainhour, Lisa, Wekezer, Jerry W., Florida State University, College of Engineering, Department of Civil and Environmental Engineering
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Abstract/Description: The State of Florida acquires over 300 cutaway buses every year. The increasing popularity of such buses raised concerns about passenger safety and overall crashworthiness of this transportation mode. Dimensions of the cutaway buses and their two-stage manufacturing process made them exempted from safety standards which were developed for smaller passenger cars as well as for large coaches. To fill this gap, cutaway bus manufacturers try to demonstrate the strength of their bus roof...
Show moreThe State of Florida acquires over 300 cutaway buses every year. The increasing popularity of such buses raised concerns about passenger safety and overall crashworthiness of this transportation mode. Dimensions of the cutaway buses and their two-stage manufacturing process made them exempted from safety standards which were developed for smaller passenger cars as well as for large coaches. To fill this gap, cutaway bus manufacturers try to demonstrate the strength of their bus roof structures by using FMVSS 220 standard, which follows conservative quasi-static load tests for school buses in the US. However, more advanced, dynamic based safety standard - Regulation 66, was developed in Europe. It is based on a dynamic rollover test which more closely resembles an actual rollover accident. A cutaway bus is placed on a tilt table 800 mm above a concrete slab. The bus is tilted until it falls and impacts the concrete deck and the deformation of the sidewalls is measured in order to check if there is any intrusion into a so called 'survival space'. This standard was endorsed by 44 countries through the United Nation resolution. However, the Regulation 66 standard does not specify all the parameters regarding the rollover test. From multiple tests it can be observed that the friction between the vehicle and the concrete slab which is being impacted by the bus has an influence on the outcomes of the experiment and has great contribution to either a positive or negative assessment of the crashworthiness of a tested vehicle. This Master thesis focuses on the friction parameters between the impacting cutaway bus and a concrete slab used in the Regulation 66 standard. Due to dynamic nature of the experiment, the impact of the bus exerts a high normal force on the concrete slab. Together with an uneven and non-standard geometry of the elements in contact with the concrete deck the standard coefficient of friction found in the literature or obtained using standard tests may not hold. The proper assessment of this coefficient is important since many rollover tests are carried out numerically using Finite Element Methods. The use of numerical analysis reduces the cost of an expensive full scale rollover test. However, it requires verified and validated parameters in order to consider the results trustworthy. The experimental part of this thesis consists of designing and carrying out experiments to evaluate the coefficient of friction for an impacting cutaway bus and a concrete slab. The results from the experiments are incorporated into an explicit computer code LS-DYNA, which is used for numerical analysis of the cutaway buses. The final outcome of this thesis will be validating the coefficient of friction used in the Finite Element Analysis which will lead to improvement of the Finite Element models and will be used to check the influence of the coefficient of friction on vehicle structure deformation (Deformation Index) during rollover accidents.
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Date Issued: 2015
Identifier: FSU_2015fall_Gleba_fsu_0071N_12953
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: Driver Behavior in Mixed Connected-Automated and Conventional Vehicle Traffic at a Freeway Merge.
Creator: Chityala, Sneha, Sobanjo, John Olusegun, Ozguven, Eren Erman, Spainhour, Lisa, Florida State University, College of Engineering, Department of Civil and Environmental Engineering
Abstract/Description: Wireless communication through automated and connected vehicles is an evolving technology. This ameliorates the driving conditions, reduces time spent in traffic and curtails the crash occurrences. One of the most challenging areas, where these interactions can be most useful, are freeway merge ramps. Both the drivers on mainline and the drivers merging would be skeptical about their decisions at this location. The drivers who want to merge to the freeway mainline would seek to find an...
Show moreWireless communication through automated and connected vehicles is an evolving technology. This ameliorates the driving conditions, reduces time spent in traffic and curtails the crash occurrences. One of the most challenging areas, where these interactions can be most useful, are freeway merge ramps. Both the drivers on mainline and the drivers merging would be skeptical about their decisions at this location. The drivers who want to merge to the freeway mainline would seek to find an appropriate gap to enter the mainline of the freeway. While the technology of connected and automated vehicles is being promoted, the reality now is that for the foreseeable future, the traffic would not comprise 100% of such connected and automated vehicles. In other words, there will be a mixed traffic of manually-driven and connected/automated vehicles, with various levels of automation in the latter types of vehicles. Capturing the driver behavior at the merge locations into a freeway with such mixed traffic, will be useful in learning and improving safety on the roadways. The Driving Simulator is a useful device in capturing driver behaviors. In this study scenarios are developed in the Driving Simulator which allows mixed traffic on mainline and also observe the driver behaviors from the ramp onto the merge. Overall there were three variations in the mixed traffic flow for the mainline freeway: 0%, 50% and 75% penetration rates. The freeway traffic was generated for the mixed traffic by first developing a mixed probability distribution which assumes exponential distributions for the inter-arrival times of manually-driven vehicles and a constant headway (uniform distribution) is assumed between connected vehicles. The mixed distribution was then used to randomly generate vehicles through Monte Carlo simulation, with assigned headways in the Driving Simulator for the various connected vehicle penetration rates. The subject driver’s speed along the ramp is monitored, as well as the speeds of those vehicles on the freeway. The gaps between freeway vehicles, which were accepted by the subject driver, were recorded for the various situations and scenarios. There were a total of 41 participants, with 29 young drivers (younger than 65 years) and 12 elderly drivers (65 years and older, amongst which 2 were between 55 and 65 years old). Three scenarios were presented to the drivers. The first driving task was to determine headway gap acceptance for the three penetration rates, based on the perception of the subject drivers (without driving). The second test involved the subjects actually driving on the ramp and implementing a suitable gap to merge on the freeway traffic at each ramp. From the data collected, the critical gaps were estimated based on perception. The gaps accepted while driving were also tabulated analyzed. It was observed that the critical gap for the young drivers in 0%, 50%, 75% penetrations rate are 2.9 sec, 1.8 sec, and 1.7 sec respectively. The critical gaps observed for elderly drivers aged over 65 are 3.5 sec, 2.0 sec, and 1.9 sec respectively. Based on an Analysis of Variance (ANOVA), there is no evidence to prove the equality of means for different groups classified by age, gender and driving experience in both perception and actual driving conditions for 0% and 50% penetration rates. It was observed that the headway gaps accepted by young and drivers, both by perception and driving in 0% penetration rate were 2.39 sec and 2.35 sec respectively. The headway gaps accepted by elderly drivers both by perception and driving in 0% penetration rate were 2.4 sec and 2.72 sec respectively. When the ANOVA was performed between the 0% and 50% penetration rates of driving conditions, it was observed that there is a lot of variation in the mean headway gaps accepted. The values of average headway gaps accepted for young drivers were estimated as 2.36 sec and 1.53 sec respectively, in the 0% and 50% penetration rates. For the elderly drivers the average headway gap values observed were 2.72 sec and 1.55 sec respectively, in the 0% and 50% penetration rates traffic. The results also indicated the subject driver acceleration and deceleration behavior at the merge ramp. The results also showed that when the (aggressive) drivers accelerated to match the velocity of mainline traffic and merged in between connected-automated vehicles with the shortest gap, effects were noticed on the mainline traffic, where the main line traffic had to decelerate rapidly. Overall, it was observed that the subject drivers accepted shorter headway gaps as the penetration rates increases.
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Date Issued: 2017
Identifier: FSU_SUMMER2017_Chityala_fsu_0071N_14121
Format: Thesis

Title: Optimization of Alternative Wind Turbine Towers in Low Wind Resource Regions.
Creator: Al-Kaimakchi, Anwer, Jung, Sungmoon, Rambo-Roddenberry, Michelle Deanna, Spainhour, Lisa, Florida State University, FAMU-FSU College of Engineering, Department of Civil and...
Show moreAl-Kaimakchi, Anwer, Jung, Sungmoon, Rambo-Roddenberry, Michelle Deanna, Spainhour, Lisa, Florida State University, FAMU-FSU College of Engineering, Department of Civil and Environmental Engineering
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Abstract/Description: Taller wind turbines with big wheel area have been proposed for low wind speed sites, where conventional 80m tower cannot produce enough electricity. Hub height of 140m gives the potential to all 50 states to produce power from wind. However, it is not clear which tower (steel, concrete or hybrid) is economically attractive beyond 80m, or which design parameter is most critical in enabling tall yet economic tower. The aim of this paper is to come up with optimum designs for steel, concrete...
Show moreTaller wind turbines with big wheel area have been proposed for low wind speed sites, where conventional 80m tower cannot produce enough electricity. Hub height of 140m gives the potential to all 50 states to produce power from wind. However, it is not clear which tower (steel, concrete or hybrid) is economically attractive beyond 80m, or which design parameter is most critical in enabling tall yet economic tower. The aim of this paper is to come up with optimum designs for steel, concrete and hybrid towers while minimizing wind turbine cost and maximizing power production and then study the influence of changing one design variable on optimum designs. Also, it was of interest to study the effect of defining rotor dimeter of turbine as an independent design variable or as function of height. Multiple optimal solutions were obtained, which are called Pareto-optimal solutions. The design variables were chosen to be diameter, thickness, height of tower and blade radius. Design constraints were buckling, yielding, shear stresses for steel tower and ultimate and service limit states for the concrete tower. Those constraints have been used to control the stability of the tower. Different linear constraints have been applied for each tower, e.g. radius of the rotor should be less than the height of the tower. The design problem is conceptual design so detailed design is beyond scope of this research, such as the flange for the steel tower, connection between the concrete parts, and connection between the steel and concrete for the hybrid tower. Nonetheless, the cost of these parts was added to the design problem. Due to the highly constrained, non-convex and non-linear nature of the design problem, Genetic algorithm has been chosen as a solver for the problem. The towers were analyzed for operational and nonoperational aerodynamic conditions according to IEC 61400-1. A comparison of steel, concrete and hybrid towers was analyzed for heights ranging (80m-150m). Results showed that up to 95m, the cost difference was negligible between all towers options. Beyond 95m hybrid towers were dominating the solutions. For 150m hub height, concrete tower saved 12% when it is compared to its steel counterpart. Concrete base diameter decreases to less than 10m, industry preferred, when average concrete wall thickness was equal or greater than 0.4m or compressive strength of concrete increases. Increasing compressive strength of concrete by 10% also resulted in cost reduction of 2.18% for 150m hub height. Results showed that defining rotor diameter as a design variable was better than defining it as a function of height because the optimization problem had fewer constraints.
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Date Issued: 2017
Identifier: FSU_SUMMER2017_ALKAIMAKCHI_fsu_0071N_13989
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: Modeling of Complex Behaviors of Submarine Debris Flows.
Creator: Saha, Bikash C. (Bikash Chandra), Ye, Ming, Niedoroda, Alan W., Misra, Vasubandhu, Shanbhag, Sachin, Wang, Xiaoqiang, Florida State University, College of Arts and Sciences,...
Show moreSaha, Bikash C. (Bikash Chandra), Ye, Ming, Niedoroda, Alan W., Misra, Vasubandhu, Shanbhag, Sachin, Wang, Xiaoqiang, Florida State University, College of Arts and Sciences, Department of Scientific Computing
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Abstract/Description: Submarine debris flows are hazards when they threaten the facilities that are built on sea floor to facilitate submarine transportation. The dynamics of submarine debris flow is simple once the debris material gets in the flow motion and that it can be represented using simple physics. A two-dimensional model with two-layer Bingham fluid representations, SDFlow2D, was developed by using an Eulerian frame of reference to predict the consequences of complex submarine debris flows. The model was...
Show moreSubmarine debris flows are hazards when they threaten the facilities that are built on sea floor to facilitate submarine transportation. The dynamics of submarine debris flow is simple once the debris material gets in the flow motion and that it can be represented using simple physics. A two-dimensional model with two-layer Bingham fluid representations, SDFlow2D, was developed by using an Eulerian frame of reference to predict the consequences of complex submarine debris flows. The model was viscoplastic in nature based on depth-averaged approximation to the Shallow Water Equations (SWE), and it assumes that the flow consists of a non-deforming upper layer riding on a deforming layer. The model was verified by comparing the numerical solution with experimental observations as well as with an analytical solution. The comparison shows a good agreement with analytical solution and an acceptable agreement with experimental observations. The model was found to be capable of simulating real-word submarine debris flows. The consequence of bed material entrainment is worth studying as this process adds antecedent sediment to the debris flow mass that in turn increases the intensity of hazard. The modeling code SDFlow2D was enhanced by using simple physics to include the capability of computing bed material entrainment. It was assumed that no inertial force was involved in the process, and that the entrainment was instantaneous. The modified SDFlow2D was applied to two idealized cases and to a prognostic case. A total variation diminishing (TVD) scheme with flux limiter was applied with MacCormack predictor-corrector scheme to smooth out the spurious solution near the source area of debris flow. While the TVD scheme served that purpose to some extent, it was not helpful to make the model robust as the computational time was 15 times greater than that of using the code without TVD scheme. The Bayesian inverse modeling was implemented to quantify the Bingham parameters uncertainty. The technique helps find not only the most probable pair of Bingham parameters but also the distribution of the parameters by conducting a small number of model simulations. The overall outcome of the study benefits the deep sea explorers as well as the designers and planners in charge of designing the submarine structures.
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Date Issued: 2017
Identifier: FSU_2017SP_Saha_fsu_0071E_13595
Format: Thesis

Title: Risk-Benefit Analysis and Optimization of LEED-Certified School Buildings Design and Construction: Statisitical and Machine Learning Approaches.
Creator: Doczy, Ryan Daniel, Boot, Walter Richard, Sobanjo, John Olusegun, Spainhour, Lisa, Florida State University, College of Engineering, Department of Civil and Environmental...
Show moreDoczy, Ryan Daniel, Boot, Walter Richard, Sobanjo, John Olusegun, Spainhour, Lisa, Florida State University, College of Engineering, Department of Civil and Environmental Engineering
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Abstract/Description: As the strategy of green building becomes more and more popular due to a combination of environmental and economic concerns, there develops a need for clearly being able to understand the potential implications for choosing green strategies over conventional building practices. Some of the regions of interest consist of the additional upfront costs associated with green practices, potential life-cycle benefits associated with green building components, potential energy savings, and the...
Show moreAs the strategy of green building becomes more and more popular due to a combination of environmental and economic concerns, there develops a need for clearly being able to understand the potential implications for choosing green strategies over conventional building practices. Some of the regions of interest consist of the additional upfront costs associated with green practices, potential life-cycle benefits associated with green building components, potential energy savings, and the ability to reduce emissions. Many of these areas can potentially be forecasted with a fair degree of certainty (e.g. energy consumption, additional upfront costs); however, some elements of green building are less well defined. One such area consists of the ability of green buildings to improve the productivity and well-being of its inhabitants through an improved indoor environmental quality (IEQ). It is difficult to grasp just how much a healthier and cleaner environmental can impact a person’s cognitive functions, mental state, and physical health. Several studies shown in the literature review of this paper lead show a positive correlation between green buildings and reductions in asthma symptoms, depression symptoms, improved well-being due to reductions in contaminants, a reduction in sick building syndrome (SBS) and building related illness (BRI). This paper aims to do what many have done before in attempting to quantify the potential impact that sustainable buildings can have on its occupants; however, the scope and methods to determine these potential correlations will differ. Perhaps the most noticeable difference will be in the paper’s focus on attempting to measure the potential impact that LEED (Leadership in Energy and Environmental Design) accredited schools have on their student occupants by measuring their productivity via the use of standardized test scores and attendance rates compared to those students in conventional (non-LEED) schools. To develop a balanced analysis, the paper will control for various school-related and socio-economic factors (e.g. economic status, race, percent of teachers with a Master’s degree or higher). To make a judgement on the effect that sustainability has on academic achievement and student wellbeing, 2 sample t-tests, regression analysis, and M5P decision trees will be implemented to determine if there are significant differences between LEED and conventional schools and to determine the relationship between LEED and non-LEED parameters on student achievement and wellbeing metrics. To ensure that a large population of students from across the nation are accounted for, the study intends on investigating at least three states-worth of student data. These states (Florida, New York and Virginia) are in different climates, thus allowing for an examination of the potential differences between the various climate zones and building codes. Lastly, a case study building information model (BIM) of College Park Elementary School (located in Virginia) will be run through the energy modeling (EM) software, Ecotect, to provide information related to the school’s annual energy consumption, acoustics, and daylight and lighting values. An optimization equation, developed using previous literature and findings from this study, will use information from the case study in an attempt to optimize its academic performance. The equation will attempt to minimize construction and operational costs while maximizing student performance metrics. The optimization equation will be run through NEOS server’s Nonlinearly Constrained Optimization, Knitro. The purpose of this study is to inform those decision-makers involved in the construction of schools, and who may be interested in obtaining LEED certification for the school, to what extent the LEED schools benefit the school’s student academic achievement levels. Accounting for soft benefits (e.g. productivity, morale, general wellbeing) in a cost-benefit analysis invites an element of risk due to the difficulties in soliciting, obtaining, and accurately measuring these performance metrics. When considering fields involving knowledge work, accurately measuring productivity is an inexact science that normally requires building occupants to perform self-examinations. The results from these examinations are reliant on the occupant’s perceptions and could be open to bias. This study avoids self-assessments through its use of standardized testing as a measure for productivity. The proposed outcome of this paper is that the impacts of LEED schools on their occupants’ academic achievement, health, and wellbeing will be better understood and easier to quantify. The authors hypothesize that LEED schools will outperform conventional schools, which can be attributed to improved IEQ due to tighter building envelopes, increased ventilation rates, better filtration, a reduction in building or cleaning products containing volatile organic compounds, etc. An absence of this data could point to the inability of LEED schools to directly impact their students in a meaningful way, particularly its Indoor Environmental Quality credits, which means that LEED could have to rethink its standards if it wishes to truly improve the productivity and wellbeing of its occupants.
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Date Issued: 2018
Identifier: 2018_Su_Doczy_fsu_0071E_14648
Format: Thesis

Title: Impact of Connected and Autonomous Vehicles on Freeway Traffic Operations.
Creator: Theophilus, Oluwatosin Paul, Sobanjo, John Olusegun, Ozguven, Eren Erman, Dulebenets, Maxim A., Florida State University, College of Engineering, Department of Civil and...
Show moreTheophilus, Oluwatosin Paul, Sobanjo, John Olusegun, Ozguven, Eren Erman, Dulebenets, Maxim A., Florida State University, College of Engineering, Department of Civil and Environmental Engineering
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Abstract/Description: This project evaluates using traffic simulation, the performance of a mixed traffic composition of Connected and Autonomous Vehicles (CAV) and conventional or human-driven vehicles, in comparison with the performance of the existing traffic composition of only conventional vehicles on a freeway segment. The introduction of CAVs into the existing transportation system is a phase in the evolution of automobile traffic currently generating a lot of concerns and questions that needs to be...
Show moreThis project evaluates using traffic simulation, the performance of a mixed traffic composition of Connected and Autonomous Vehicles (CAV) and conventional or human-driven vehicles, in comparison with the performance of the existing traffic composition of only conventional vehicles on a freeway segment. The introduction of CAVs into the existing transportation system is a phase in the evolution of automobile traffic currently generating a lot of concerns and questions that needs to be answered before the full deployment of these vehicles. Traffic simulation presents a safer and cost-effective approach to evaluating this innovative technology when compared with real world testing. Connected and autonomous vehicles (CAV) are designed to improve traffic operations, as the difference in their driving behavior from regular vehicles suggests a reasonable tendency to change the traffic flow pattern. However the issue being examined in this project is whether there would be a significant change in traffic operations resulting from their deployment, and also to verify whether the change is an improvement of the existing traffic condition in terms of performance measures used for the evaluation. Data was collected from the I-95 Freeway in South Florida, and used in the development of a traffic microsimulation model, in VISSIM. The model was calibrated using minimum error algorithm implemented in MATLAB to determine the optimal value of the two model parameters considered -- stand still distance (CC0), and headway time (CC1). The calibrated model was used as the base model and CAVs are incorporated into the base model in 10% increment, to examine their effect on the base model. The performance measures are average hourly speed, hourly traffic volume, travel time, delay, and safety. Findings show that for every increment in CAV market penetration, there is a change of 6.52% - 48% in the capacity of the freeway, 40% reduction in travel time, more than 30% reduction in delay per vehicle, more than 26% increase in average speed of the traffic at high demand volumes.
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Date Issued: 2018
Identifier: 2018_Su_Theophilus_fsu_0071N_14809
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: Damage Detection in Reinforced Concrete Structures with In-Situ Triboluminescent Optical Fiber Sensors.
Creator: Kliewer, Kaitlyn, Department of Civil and Environmental Engineering
Abstract/Description: With the increased aging and deterioration of civil infrastructure systems, it is crucial to develop an effective and economical structural health monitoring system. Current structural health monitoring systems are burdened by disadvantages rendering them inefficient or not economically viable. In response to this problem, the in-situ triboluminescent optical fiber (ITOF) sensor has been developed for applications within cementitious structures. Four point bend tests were carried out on...
Show moreWith the increased aging and deterioration of civil infrastructure systems, it is crucial to develop an effective and economical structural health monitoring system. Current structural health monitoring systems are burdened by disadvantages rendering them inefficient or not economically viable. In response to this problem, the in-situ triboluminescent optical fiber (ITOF) sensor has been developed for applications within cementitious structures. Four point bend tests were carried out on reinforced concrete beams with integrated ITOF sensors so as to evaluate the performance of the sensor. With this study, the ITOF sensor's potential to provide in-situ and distributed real time damage detection within concrete structures has been demonstrated. Reinforced concrete beams instrumented with the ITOF sensor provided warning signals and real time feedback prior to the failure of the beam through triboluminescent signal peaks and demonstrated the potential as a viable SHM system. Both the length and sensor location within the reinforced beams were tested. Test results indicated that a longer sensitized region of the ITOF sensor and a sensor placed closer to the tension face of the beam yielded higher damage (triboluminescent) response signals.
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Date Issued: 2013
Identifier: FSU_migr_uhm-0236
Format: Thesis

Title: Accelerated Slab Replacement Using Temporary Precast Panels and Self Consolidating Concrete.
Creator: Squillacote, Steven C., Tawfiq, Kamal Sulaiman, Rambo-Roddenberry, Michelle Deanna, Spainhour, Lisa, Kampmann, Raphael, Florida State University, FAMU-FSU College of Engineering...
Show moreSquillacote, Steven C., Tawfiq, Kamal Sulaiman, Rambo-Roddenberry, Michelle Deanna, Spainhour, Lisa, Kampmann, Raphael, Florida State University, FAMU-FSU College of Engineering, Department of Civil and Environmental Engineering
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Abstract/Description: As it stands, many of Florida’s roads have already reached their designed service life and are now in the process of being renewed. The current method in rehabilitation of concrete pavement requires the expired piece of pavement to be cut and removed, place new dowel bars, and then epoxied into the surrounding slabs. Once the slab area has been prepared, fresh concrete is poured, and finished. The concrete is then cured and monitored to achieve a strength requirement of 2,200 psi in the...
Show moreAs it stands, many of Florida’s roads have already reached their designed service life and are now in the process of being renewed. The current method in rehabilitation of concrete pavement requires the expired piece of pavement to be cut and removed, place new dowel bars, and then epoxied into the surrounding slabs. Once the slab area has been prepared, fresh concrete is poured, and finished. The concrete is then cured and monitored to achieve a strength requirement of 2,200 psi in the shortest possible time before the lanes can be opened for traffic. This event has been known to take a long time and on major highways lane where lane closure may not exceed 8 hours. This restriction limits the number of slabs that can be replaced. The types of concrete used on these projects are also problematic. In the past, high amounts of cementitious material was used and this can lead to premature cracking. To improve production levels, accelerate construction time at a reduced cost, and provide long lasting pavement, the current research study presents an alternative method of using precast slab panels and self-consolidating concrete. This was accomplished by testing several SCC mixes in the laboratory to achieve concrete with high workability without, high early strength and without segregation. Then, precast panels were designed and built for quick installation and removal. This study also necessitated full scaled field tests where precast slab panels with the proper SCC mix were used. The slabs were tested by a loaded truck moving over it repeatedly and the slab was monitored for any movement and displacements caused by driving and braking on it. After the data was collected from the precast panels, the slabs were then removed and fresh SCC was then poured into the empty pit. The SSC slab was left to cure and the maturity of the concrete was monitored to achieve the required strength for lane opining. In this study, three techniques were used to monitor the concrete maturity. These techniques involved the use of the conventional thermocouples, thermal camera, and laser gun. The traffic load was then applied by driving a dump truck loaded to 25000 pounds over the track for 100 laps. The SCC mix behaved as designed and presented in this study. It achieved a high workability and retained a high slump for nearly an hour. It also exceeded the required FDOT strength requirement of 2200 psi for lane opening. The precast panels proved to be highly durable during the installation, testing, removal and can be reused for other similar applications. Results from this study proved proved that using this method has several benefits including greater productivity, reduced maintenance of traffic, shorter project completion time. Further, it may reduce the case of premature cracking due to the increase amount of curing time.
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Date Issued: 2018
Identifier: 2018_Su_Squillacote_fsu_0071N_13474
Format: Thesis

Title: Dynamic and Stochastic Transition of Traffic Conditions and Its Application in Urban Traffic Mobility.
Creator: Kidando, Emmanuel, Moses, Ren, Duncan, Michael Douglas, Ozguven, Eren Erman, Sobanjo, John Olusegun, Sando, Thobias M., Florida State University, FAMU-FSU College of Engineering...
Show moreKidando, Emmanuel, Moses, Ren, Duncan, Michael Douglas, Ozguven, Eren Erman, Sobanjo, John Olusegun, Sando, Thobias M., Florida State University, FAMU-FSU College of Engineering, Department of Civil and Environmental Engineering
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Abstract/Description: Analytical models developed using field data can provide useful information with acceptable confidence to evaluate and predict the operational characteristics of a highway. As such, this study presents statistical models that can be used to estimate the travel time or speed distribution, cluster different traffic conditions, to model the dynamic transition of traffic regimes (DTR), and quantify the disparity-effects on the DTR associated with different lateral lane positions (i.e., lane near...
Show moreAnalytical models developed using field data can provide useful information with acceptable confidence to evaluate and predict the operational characteristics of a highway. As such, this study presents statistical models that can be used to estimate the travel time or speed distribution, cluster different traffic conditions, to model the dynamic transition of traffic regimes (DTR), and quantify the disparity-effects on the DTR associated with different lateral lane positions (i.e., lane near shoulder, middle lane(s) and lane near a median) as well as different days of the week. In the analysis, this study uses Bayesian frameworks to estimate the model parameters. These frameworks reduce the impact of model over-fitting and also incorporate uncertainty in the estimates. Data from a freeway corridor along I-295 located in Jacksonville, Florida were selected for analysis. It includes data from individual microwave vehicle sensors, segment level aggregated traffic data and data aggregated at a corridor level. The proposed probabilistic frameworks developed by this study can be a useful resource in detecting and evaluating different traffic conditions, which can facilitate the planning action to implement congestion-related countermeasures in urban areas. In addition, findings from the hierarchical regression model presented by the current study can be used in the application of intelligent transportation systems, mainly in the dynamic lane-management strategy.
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Date Issued: 2019
Identifier: 2019_Spring_Kidando_fsu_0071E_15049
Format: Thesis

Title: Analysis of Composite Timber Studs: An Optimization of Tall Wall Structures.
Creator: Solek, Ashley, Rambo-Roddenberry, Michelle Deanna, Jung, Sungmoon, Kampmann, Raphael, Spainhour, Lisa, Florida State University, FAMU-FSU College of Engineering, Department of...
Show moreSolek, Ashley, Rambo-Roddenberry, Michelle Deanna, Jung, Sungmoon, Kampmann, Raphael, Spainhour, Lisa, Florida State University, FAMU-FSU College of Engineering, Department of Civil and Environmental Engineering
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Abstract/Description: The National Design Specification for Wood Construction (NDS) outlines different factors and equations necessary for designing structures exploiting timber. While analyzing a timber shear wall there are several specific equations and restraints that the design must satisfy. These limitations come from not only the NDS, but also the Minimum Design Loads for Buildings and Other Structures (ASCE7), the Florida Building Code (FBC), and the International Residential Code (IRC). ASCE7, paired with...
Show moreThe National Design Specification for Wood Construction (NDS) outlines different factors and equations necessary for designing structures exploiting timber. While analyzing a timber shear wall there are several specific equations and restraints that the design must satisfy. These limitations come from not only the NDS, but also the Minimum Design Loads for Buildings and Other Structures (ASCE7), the Florida Building Code (FBC), and the International Residential Code (IRC). ASCE7, paired with the NDS, provide a standard design methodology. The FBC and IRC focus their framework around the minimum requirements. These manuals focus on the design strength of the individual components, rather than how they react once affixed to one another. The sheathing is the foremost structural component which combats against the wind loads. Several different types of sheathing, as well as nail sizes and patterns were analyzed as a connected structure. The methodology used was similar to that of reinforced concrete, in that the properties of the nails and sheathing were transformed into that of the sawn lumber stud. This facilitated an analytical comparison between the standard design method and that of a "composite I-beam". Increases and decreases in strength were found, due to the complexity of the design equations, the addition of the sheathing component did not always enable a higher wall capacity. Deflection as the ultimate failure of the member still rang true for the new method of design.
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Date Issued: 2018
Identifier: 2018_Fall_Solek_fsu_0071N_14938
Format: Thesis

Title: Hybrid Data Mining Models for Risk and Vulnerability Analysis of Traffic Safety.
Creator: Mafi, Somayeh, AbdelRazig, Yassir, Boot, Walter Richard, Ozguven, Eren Erman, Spainhour, Lisa, Florida State University, FAMU-FSU College of Engineering, Department of Civil and...
Show moreMafi, Somayeh, AbdelRazig, Yassir, Boot, Walter Richard, Ozguven, Eren Erman, Spainhour, Lisa, Florida State University, FAMU-FSU College of Engineering, Department of Civil and Environmental Engineering
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Abstract/Description: As the roadway networks have been developing gradually to improve transportation accessibility to various facilities, the probability of traffic crash occurrences has also increased consequently. With an increasing transportation demand, traffic safety needs to be improved in order to reduce the economic and societal expenses related to improper traffic safety measures. The identification and prediction of crash-prone regions is an essential task in highway safety management, particularly...
Show moreAs the roadway networks have been developing gradually to improve transportation accessibility to various facilities, the probability of traffic crash occurrences has also increased consequently. With an increasing transportation demand, traffic safety needs to be improved in order to reduce the economic and societal expenses related to improper traffic safety measures. The identification and prediction of crash-prone regions is an essential task in highway safety management, particularly when highway officials have a limited budget for mitigations. Generally, implementing effective methods for the prediction of high crash risk locations can facilitate research on contributing factors in traffic crashes to mitigate them, resulting in the efficient employment of federal, state and local government resources for enhancing transportation safety. In this regard, developing non-biased and accurate models capable of predicting crash risk is a vital task in transportation safety research. Another transportation issue, believed to have a close relationship with traffic safety and operation, is drivers’ gap acceptance behavior. Given the steady rise in the percentage of aging roadway users in the United States and their over-represented engagement in fatal crashes, there is a growing need for understanding how this population differs from their younger counterparts in driving performance and crash involvement. The general objective of this research is to develop hybrid data mining models for risk and vulnerability analysis of traffic safety. This research examines the feasibility of different data mining models in predicting the priority of intersections needing improvement for aging drivers by comparing their results with traditional models. It also investigates how injury severity differs between drivers of various age and gender groups by developing cost-sensitive data mining models which consider the consequences (cost) of incorrect predictions. Moreover, it examines the effect of time-based accessibility to on-premise alcohol outlets on the severity of alcohol-related crashes. This research also conducts Geographical Information System (GIS)-based hotspot analyses to identify the crash-prone locations for various occupant age groups during different time intervals of a day and predict the location of these hotspots using statistical and machine learning models. Besides, it conducts a spatiotemporal analysis to quantify the exposure of population of different age groups to crash-prone locations and to statistically analyze the decision-making process for possible improvement. This study also aims to investigate the differences in drivers’ gap acceptance behavior while performing permissive left and right turn maneuvers at four-legged intersections using the data extracted from a driving simulator. The results showed that the implemented machine learning models were superior methodologies for predicting crash risk. Moreover, the cost-sensitive learning classifiers outperformed regular classifiers at accurately predicting injuries and fatalities of crashes. Results of the crash severity models displayed substantial differences in injury severity determinants across the age/gender cohorts. Also, it was concluded that more accessibility to on-premise alcohol outlets results in more severe alcohol-related crashes. The hotspot prediction models also revealed considerable differences in crash hotspot determinants and their coefficients across the occupants’ age groups and time intervals of a day. Moreover, among the residents, the aging population were shown to be more exposed to the risk of being injured in a crash compared to other age groups. The results of driving simulation experiment also illustrated that aging drivers are more conservative in performing left turns than younger drivers, and accepted gap size, number of lanes, and the presence of pedestrians were significantly correlated with drivers’ gap acceptance behavior.
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Date Issued: 2019
Identifier: 2019_Spring_Mafi_fsu_0071E_14997
Format: Thesis

Title: Multilevel Competing Risks Models for the Performance Assessment of Transportation Infrastructure.
Creator: Inkoom, Sylvester Kwame, Sobanjo, John Olusegun, Chicken, Eric, AbdelRazig, Yassir, Spainhour, Lisa, Florida State University, FAMU-FSU College of Engineering, Department of...
Show moreInkoom, Sylvester Kwame, Sobanjo, John Olusegun, Chicken, Eric, AbdelRazig, Yassir, Spainhour, Lisa, Florida State University, FAMU-FSU College of Engineering, Department of Civil and Environmental Engineering
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Abstract/Description: Natural disasters such as hurricanes, earthquakes, storm surges, wildfires among other hazards affect communities and large geographic areas of the United States resulting in negative repercussions on the environment and the economy. The impacts of these hazards on bridges and other civil infrastructure affect the structural integrity and functionality of bridges, highway pavements and overall efficiency of the transportation network. This study focuses on the hazards that affect bridges and...
Show moreNatural disasters such as hurricanes, earthquakes, storm surges, wildfires among other hazards affect communities and large geographic areas of the United States resulting in negative repercussions on the environment and the economy. The impacts of these hazards on bridges and other civil infrastructure affect the structural integrity and functionality of bridges, highway pavements and overall efficiency of the transportation network. This study focuses on the hazards that affect bridges and pavements, and the complex interactions and correlations among them, to evaluate the performance of civil infrastructure. Hazard scenarios are considered as competing risks impacting the health of bridges and highway pavements. The study derived stochastic distributions characterizing the behavior of bridge elements and pavement segments during natural deterioration process which are compared to their response in the presence of hazards. To achieve the above objective, competing risk models were developed for highway pavement in Florida in the presence of hurricane failures. Also, distributions and competing risk deterioration models for AASHTO Commonly Recognized (CoRe) bridge elements were developed using legacy data for bridges from the Florida Department of Transportation (FDOT). Annual probability of hazard occurrence data sourced from Federal Emergency Management Agency (FEMA – HAZUS) was employed to model hurricane induced pavement and bridge element failure. The expected service lives for highway pavement and bridge elements, transition and sojourn times from one condition state to another were obtained using the Cox Proportional Hazards, cumulative incidence functions, product-limit survival estimates and other survival functions. The method of likelihood estimation, weighting techniques and inference procedures were used to describe risk event data with censoring and truncation scenarios where necessary for the analyses. The cumulative incidence function and the Kaplan – Meier estimates were used to ascertain the effects of the modes of failures of bridge elements and highway pavements at the network levels in the presence of hurricanes. The results showed that three modes of failure (cracking, riding and rutting) are all significant to for pavements. As the roadway pavement section ages, the chance of failure is more likely to be due to cracking than the other competing modes. Based on the road functional classifications, the survival probabilities and the cumulative incidence estimates showed that the cracking defect was predominant on both interstate and non-interstate roadways. It was observed that urban and rural pavements deteriorated by the cracking and riding defects with the rutting failure mode being significant at the end of the service life of the pavement. The research also evaluated the significance of two competing risks events: “natural” crack deterioration of highway pavements in the presence of hurricane failure (Hurricane Categories 1, 2 and 3), for 6702 highway pavement sections using the nonparametric survival probability (Kaplan-Meier estimates) and the cumulative incidence function (CIF). The risks were compared using the Logrank Test (to indicate if the survival probabilities of the risks are significantly different), and the hazard ratio (ratio of hazard rates based on time to failure covariate). From the results, it was observed that the contribution of the Hurricane Category 3 as a competing risk was significantly higher and different from that of crack deterioration. For example, the hazard ratio indicated the effect of Hurricane Category 3 on pavement failure was twice as significant as that of the crack deterioration for the inland urban interstates roadways. Also, the hazard ratio between hurricane category 3 and crack deterioration was about 16 for rural interstates and 18 and 28 for urban non-interstates and rural non-interstates at the coastal locations respectively. The hazard ratios and CIF plots showed that impact of hurricanes on coastal roadways is more significant compared to how they affect the inland pavements. Finally, it was observed that the “natural” deterioration of bridge channels and hurricane induced channel failures generally yield significantly different impacts based on the logrank chi-square outputs. Also, it was observed the impact of hurricane categories 3 and 2 on bridge channel elements were more significant (based on the hazard ratios) at the coastal bridge locations than in the noncoastal areas, and also generally high for urban bridge channels compared to rural channels.
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Date Issued: 2019
Identifier: 2019_Spring_Inkoom_fsu_0071E_14979
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

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