Current Search: 1783-1809 (x) » Department of Civil, Environmental and Geomatics Engineering (x)
View All Items
Pages
- Title
- Development of functional relationships between radar and rain gage data using inductive modeling techniques.
- Creator
- Peters, Delroy., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
Traditional methods such as distance weighing, correlation and data driven methods have been used in the estimation of missing precipitation data. Also common is the use of radar (NEXRAD) data to provide better spatial distribution of precipitation as well as infilling missing rain gage data. Conventional regression models are often used to capture highly variant nonlinear spatial and temporal relationships between NEXRAD and rain gage data. This study aims to understand and model the...
Show moreTraditional methods such as distance weighing, correlation and data driven methods have been used in the estimation of missing precipitation data. Also common is the use of radar (NEXRAD) data to provide better spatial distribution of precipitation as well as infilling missing rain gage data. Conventional regression models are often used to capture highly variant nonlinear spatial and temporal relationships between NEXRAD and rain gage data. This study aims to understand and model the relationships between radar (NEXRAD) estimated rainfall data and the data measured by conventional rain gages. The study is also an investigation into the use of emerging computational data modeling (inductive) techniques and mathematical programming formulations to develop new optimal functional approximations. Radar based rainfall data and rain gage data are analyzed to understand the spatio-temporal associations, as well as the effect of changes in the length or availability of data on the models. The upper and lower Kissimmee basins of south Florida form the test-bed to evaluate the proposed and developed approaches and also to check the validity and operational applicability of these functional relationships among NEXRAD and rain gage data for infilling of missing data.
Show less - Date Issued
- 2008
- PURL
- http://purl.flvc.org/FAU/166454
- Subject Headings
- Weather control, Mathematical models, Radar meteorology, Technological innovations, Precipitation (Meteorology), Measurement, Weather forecasting, Technological innovations
- Format
- Document (PDF)
- Title
- Farfield modeling of the Boynton Inlet plume using sulfur hexafluoride as tracer.
- Creator
- Pire-Schmidt, Joaquin., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
The analysis and modeling of the coastal farfield behavior of inlet discharge plumes is the key to understanding the fate of pollutants discharged into the ocean. These plumes disperse in chaotic and unpredictable patterns. Theoretical models are based on the average conditions and calibrated to the results of tracer studies. Data and models for freshwater discharges in coastal ocean systems are limited because of the lack of adequate tracers. On February, 2007, a tracer study was conducted...
Show moreThe analysis and modeling of the coastal farfield behavior of inlet discharge plumes is the key to understanding the fate of pollutants discharged into the ocean. These plumes disperse in chaotic and unpredictable patterns. Theoretical models are based on the average conditions and calibrated to the results of tracer studies. Data and models for freshwater discharges in coastal ocean systems are limited because of the lack of adequate tracers. On February, 2007, a tracer study was conducted on the Boynton Inlet, Florida, using sulfur hexafluoride (SF6) tracer. The objective of this study is to provide methods of analysis for the sample data collected during the experiment. The detected tracer concentrated in a bolus that migrated north of the inlet at velocities lower than predicted by the current data. The plume was successfully modeled with a Gaussian plume model, with 90% of the SF6 predictions having less than 4.6 pptr error.
Show less - Date Issued
- 2009
- PURL
- http://purl.flvc.org/FAU/186771
- Subject Headings
- Plumes (Fluid dynamics), Water, Pollution, Sedimentation and deposition, Environmental aspects, Pollution, Mathematical models
- Format
- Document (PDF)
- Title
- A mixed integer nonlinear programming model to optimize the use of aircraft deicing and anti-icing fluids.
- Creator
- Ornitz, Scott E., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
A detailed study is proposed for understanding the use of aircraft deicing and anti-icing fluids (ADAF) and optimal use of these fluids in airport operations. A detailed literature review of past and current technologies is conducted and possible opportunities to improve the use of ADAF and relevant recommendations are derived. Mathematical optimization models (e.g. MINLP with binary variables) based on a variety of objectives, which deal with exhaustive sets of system constraints are...
Show moreA detailed study is proposed for understanding the use of aircraft deicing and anti-icing fluids (ADAF) and optimal use of these fluids in airport operations. A detailed literature review of past and current technologies is conducted and possible opportunities to improve the use of ADAF and relevant recommendations are derived. Mathematical optimization models (e.g. MINLP with binary variables) based on a variety of objectives, which deal with exhaustive sets of system constraints are formulated, developed and applied to case studies. One real-life case study area which routinely carries out aircraft deicing is used for testing the mathematical optimization formulations for optimal use of fluids under budgetary and environmental compliance constraints. Based on the recommendations from one of the best optimization model formulations it is hoped that it will be used for a real-time implementation. Results from these formulations show the models to be robust and applicable.
Show less - Date Issued
- 2009
- PURL
- http://purl.flvc.org/FAU/192987
- Subject Headings
- Deicing chemicals, Testing, Airplanes, Ice prevention, Programming (Mathematics)
- Format
- Document (PDF)
- Title
- A comparison of non-traditional instersection designs using microscopic simulation.
- Creator
- Chery, Steve, College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
In light of the growing traffic demand and the futility of the conventional solutions, many states have been considering alternative intersection designs. Researchers have demonstrated the benefits of several unconventional intersection designs and their implementation at different sites throughout the United States and abroad have delivered significant improvement in traffic compared to the conventional intersections. A signalized and un-signalized roundabout, a Continuous Flow Intersection,...
Show moreIn light of the growing traffic demand and the futility of the conventional solutions, many states have been considering alternative intersection designs. Researchers have demonstrated the benefits of several unconventional intersection designs and their implementation at different sites throughout the United States and abroad have delivered significant improvement in traffic compared to the conventional intersections. A signalized and un-signalized roundabout, a Continuous Flow Intersection, and a Parallel Flow Intersection have been evaluated and compared in this research as viable alternatives to the traditional single intersection. Using micro-simulation platforms, AIMSUN 6.0 and VISSIM 5.10, models of each intersection are evaluated for low, medium, and high entrance volumes. The analysis revealed that the Roundabout performs better at low entering volumes while the Continuous flow yields better results at high volumes.
Show less - Date Issued
- 2010
- PURL
- http://purl.flvc.org/FAU/1927863
- Subject Headings
- Traffic engineering, Streets, Design, City planning
- Format
- Document (PDF)
- Title
- Transit signal priority for emergency evacuation: mitigating disaster.
- Creator
- Parr, Scott A., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
The goal of this research is to answer a single question. During an urban evacuation, is it advisable for regional planners to allow transit units signal priority in cases where police assisted traffic controls are not an option? Standard practice for emergency evacuation is to place police officers at intersection throughout the evacuation area. However, this is not always an option where environmental factors such as the presence of fire, chemical plume, radioactive fallout (nuclear...
Show moreThe goal of this research is to answer a single question. During an urban evacuation, is it advisable for regional planners to allow transit units signal priority in cases where police assisted traffic controls are not an option? Standard practice for emergency evacuation is to place police officers at intersection throughout the evacuation area. However, this is not always an option where environmental factors such as the presence of fire, chemical plume, radioactive fallout (nuclear contaminated wind and dust) do not permit police presence. Results from a case study conducted on Washington D.C. show that it would take four non-prioritized transit units to accomplish the same task as three prioritized vehicles. Furthermore, allowing transit signal priority during an urban evacuation has little to no effect on evacuation clearance time or evacuee travel time. Moreover, when transit signal priority is restricted to operate only on evacuation routes, evacuee travel and delay time decreases.
Show less - Date Issued
- 2010
- PURL
- http://purl.flvc.org/FAU/1930488
- Subject Headings
- Emergency transportation, Government policy, Emergency management, Evacuation of civilians, Electronic traffic controls
- Format
- Document (PDF)
- Title
- Use of hybrid Rice Husk Ash-Fly Ash mixtures as sustainable supplementary materials for concrete in the marine environment.
- Creator
- Arboleda, Diana., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
This paper presents the comparison of shrinkage and corrosion characteristics of optimized hybrid Rice Husk Ash (RHA)/Fly Ash (FA)-modified Concrete, with those of normal concrete in the marine environment. Uses of both FA and RHA have numerous environmental benefits. Shrinkage performance was determined by subjecting the mixes to restrained shrinkage testing per ASTM C1581. The time to cracking of the specimens improved an average of 18% with the hybrid mixes. Corrosion testing of reinforced...
Show moreThis paper presents the comparison of shrinkage and corrosion characteristics of optimized hybrid Rice Husk Ash (RHA)/Fly Ash (FA)-modified Concrete, with those of normal concrete in the marine environment. Uses of both FA and RHA have numerous environmental benefits. Shrinkage performance was determined by subjecting the mixes to restrained shrinkage testing per ASTM C1581. The time to cracking of the specimens improved an average of 18% with the hybrid mixes. Corrosion testing of reinforced columns was performed in a simulated tidal cycle Marine Environment. Corrosion potential improved by as much as 35% for the mix with the highest FA/RHA replacement, and corrosion activity as measured with potentiostat equipment improved by an average of 34% . These results indicate a clear performance improvement of the modified concrete that is proportional to the percent replacement of cement.
Show less - Date Issued
- 2010
- PURL
- http://purl.flvc.org/FAU/2138109
- Subject Headings
- Fracture mechanics, Concrete, Additives, Testing, Fly ash, Testing, Concrete, Cracking, Prevention, Industrial minerals, Testing
- Format
- Document (PDF)
- Title
- An emergency evacuation planning model for special needs populations utilizing public transit systems.
- Creator
- Hess, Linda S., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
The need to have evacuation plans in place for readily implementation for special need populations has become evident after catastrophic events such as Hurricane Katrina. For the purpose of this research special need populations will include, but are not limited to, people with physical disabilities, senior citizens, non-English speaking populations, residents and employees without vehicles, and tourists. The main objective of this research is to evaluate different evacuation procedures for...
Show moreThe need to have evacuation plans in place for readily implementation for special need populations has become evident after catastrophic events such as Hurricane Katrina. For the purpose of this research special need populations will include, but are not limited to, people with physical disabilities, senior citizens, non-English speaking populations, residents and employees without vehicles, and tourists. The main objective of this research is to evaluate different evacuation procedures for special need populations from large urban areas utilizing current public transit systems. A microscopic simulation model was constructed to analyze real life scenarios for evacuation methodologies. A linear programming optimization model was developed to find the optimum locations for evacuation bus stops for the case study area. The results from this research were very interesting and can aid evacuation planners in the future.
Show less - Date Issued
- 2009
- PURL
- http://purl.flvc.org/FAU/2182085
- Subject Headings
- Evacuation of civilians, Emergency management, Emergency transportation
- Format
- Document (PDF)
- Title
- Blast/explosion resistant analysis of composite steel girder bridge system.
- Creator
- Zhou, Fang., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
The design of bridge structures to resist explosive loads has become more of a concern to the engineering community. This thesis proposes a method to evaluate the effects of conventional blast loads on a two span continuous composite steel girder bridge system. The bridge design is based on AASHTO LRFD method. Resistance capacities of bridge deck and composite steel girder are calculated according to AASHTO specifications. Equivalent blast pressures on the bridge components are obtained....
Show moreThe design of bridge structures to resist explosive loads has become more of a concern to the engineering community. This thesis proposes a method to evaluate the effects of conventional blast loads on a two span continuous composite steel girder bridge system. The bridge design is based on AASHTO LRFD method. Resistance capacities of bridge deck and composite steel girder are calculated according to AASHTO specifications. Equivalent blast pressures on the bridge components are obtained. Response and performance of concrete deck, steel girders, and supporting piers are evaluated under typical blast loads. The blast induced force in the bridge components are computed in the static analyses for varying amounts of TNT. The blast effects in the supporting pier are determined using both static and dynamic analyses. Further research needs to be done in the dynamic analysis of the bridge system subjected to blast loads.
Show less - Date Issued
- 2009
- PURL
- http://purl.flvc.org/FAU/227976
- Subject Headings
- Steel, Structural, Testing, Bridges, Design and construction, Structural dynamics
- Format
- Document (PDF)
- Title
- Collection and analyses of physical data for deep injection wells in Florida.
- Creator
- Gao, Jie., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
Deep injection wells (DIW) in Florida are regulated by the U.S. Environmental Protection Agency (USEPA) and the state of Florida through the Underground Injection Control regulations contained within the Safe Drinking Water Act. Underground injection is defined as the injection of hazardous waste, nonhazardous waste, or municipal waste below the lowermost formation containing an underground source of drinking water within one-quarter mile of the wellbore. Municipalities in Florida have been...
Show moreDeep injection wells (DIW) in Florida are regulated by the U.S. Environmental Protection Agency (USEPA) and the state of Florida through the Underground Injection Control regulations contained within the Safe Drinking Water Act. Underground injection is defined as the injection of hazardous waste, nonhazardous waste, or municipal waste below the lowermost formation containing an underground source of drinking water within one-quarter mile of the wellbore. Municipalities in Florida have been using underground injection as an alternative to surface disposal of treated domestic wastewater for nearly 40 years. The research involved collecting data as of September, 2007 on all the Class I DIWs in the state of Florida and evaluating the differences between them. The analysis found regional differences in deep well practice and canonical correlation analyses concluded that depth below the USDW is the most significant factor to prevent upward migration of the injected fluid.
Show less - Date Issued
- 2010
- PURL
- http://purl.flvc.org/FAU/2796085
- Subject Headings
- Groundwater flow, Mathematical models, Artificial groundwater recharge, Groundwater, Pollution, Management, Deep-well disposal
- Format
- Document (PDF)
- Title
- Stress distribution around a transverse circular opening through the midspan of a double reinforced beam.
- Creator
- Anesta, Heather R., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
This manuscript predicts the behavior of a doubly reinforced concrete beam with a circular opening at its midspan by closely analyzing traditional beam theory and design. It then confirms these predictions with finite element modeling software while providing design suggestions. The analysis is limited to the tensile and compressive stresses and cracking behavior. The objectives are to determine the stress distribution around a circular opening that agrees with conventional beam theory. The...
Show moreThis manuscript predicts the behavior of a doubly reinforced concrete beam with a circular opening at its midspan by closely analyzing traditional beam theory and design. It then confirms these predictions with finite element modeling software while providing design suggestions. The analysis is limited to the tensile and compressive stresses and cracking behavior. The objectives are to determine the stress distribution around a circular opening that agrees with conventional beam theory. The beam behavior is examined from zero load to failure load. ANSYS is utilized in lieu of real world testing, and the appendix includes the finite element results for a beam including design recommendations. The results lay the foundation for a possible new design procedure of concrete beams with single or multiple circular openings. This research offers useful information that was unavailable previously. More research can be conducted to help designers to design lighter, more efficient concrete beams.
Show less - Date Issued
- 2010
- PURL
- http://purl.flvc.org/FAU/2867327
- Subject Headings
- Reinforced concrete construction, Structural design, Strains and stresses, Fracture mechanics
- Format
- Document (PDF)
- Title
- Stiffness characterization and life cycle analysis of reinforced asphalt pavements using falling weight deflectometer tests.
- Creator
- Lima-Arie, Alex., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
The western and northern parts of South Florida have shallow layers of organic and plastic soils under existing roads. These roads often exhibit large amount of cracking and distortion in a short period of time. Traditional repairs are often not practical due to high costs and extended construction time. In an effort to develop rehabilitation strategies that could be strictly applied to the surface layer, a pilot test site was selected along the alignment of SR 15/US 98 in northwest Palm...
Show moreThe western and northern parts of South Florida have shallow layers of organic and plastic soils under existing roads. These roads often exhibit large amount of cracking and distortion in a short period of time. Traditional repairs are often not practical due to high costs and extended construction time. In an effort to develop rehabilitation strategies that could be strictly applied to the surface layer, a pilot test site was selected along the alignment of SR 15/US 98 in northwest Palm Beach County, where severe pavement distresses were observed due to the presence of thick organic layers. PaveTrac MT-1, GlasGrid 8501, PetroGrid 4582, and ARMI were used as promising asphalt reinforcing products in 24 experimental pavement sections, including 8 control sections without any reinforcement. A comprehensive field testing and monitoring program involving FWD, rut and ride quality measurements was conducted at the preconstruction, 6-month post-construction, and 18-month post-construction stages. Due to large variability in the sub-surface conditions, a statistics-based data analysis protocol was developed for performance evaluation and relative comparisons of the test sections and, in turn, reinforcing products. Post construction data from both 6 months and 18 months demonstrated that stiffness of reinforced sections were significantly higher than the control sections. Procedures were developed to identify and statistically quantify the benefits derived from the reinforcements only, so that the relative performance of various products could be monitored over time. Based on the field testing data available to date, a framework was developed in this study for the prediction of pavement life, which is essential for conducting a detailed Life Cycle Analysis
Show less - Date Issued
- 2010
- PURL
- http://purl.flvc.org/FAU/2976446
- Subject Headings
- Structural analysis (Engineering), Pavements, Asphalt, Performance, Management, Structural stability, Design, Pavements, Live loads, Measurement
- Format
- Document (PDF)
- Title
- Evaluation of optimal real-time reflectivity-rainfall rate (Z-R) functional relationships.
- Creator
- Pattani, Kandarp., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
Accuracy in estimation of precipitation can be achieved by utilizing the combination of spatial radar reflectivity data (Z) and the high resolution temporal rain gage based rainfall data (R). The study proposes the use of optimization models for optimizing the Z-R coefficients and exponents for different storm types and seasons. Precipitation data based on reflectivity, collected from National Climatic Data Center (NCDC) and rain gage data from Southwest Florida Water Management District ...
Show moreAccuracy in estimation of precipitation can be achieved by utilizing the combination of spatial radar reflectivity data (Z) and the high resolution temporal rain gage based rainfall data (R). The study proposes the use of optimization models for optimizing the Z-R coefficients and exponents for different storm types and seasons. Precipitation data based on reflectivity, collected from National Climatic Data Center (NCDC) and rain gage data from Southwest Florida Water Management District (SWFWMD) over same temporal resolutions were analyzed using the Rain-Radar- Retrieval (R3) system developed as a part of the study. Optimization formulations are proposed to obtain optimal coefficients and exponents in the Z-R relationships for different seasons and objective selection of storm-type specific Z-R relationships. Different approaches in selection of rain gage stations and selection of events for optimization are proposed using gradient based solver and genetic algorithms.
Show less - Date Issued
- 2010
- PURL
- http://purl.flvc.org/FAU/2978946
- Subject Headings
- Precipitation (Meteorology), Measurement, Rain and rainfall, Measurement, Reflectance, Rainfall intensity duration frequencies
- Format
- Document (PDF)
- Title
- Experimental evaluation of the durability of fly ash-based geopolymer concrete in the marine environment.
- Creator
- Edouard, Jean-Baptiste., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
The construction industry is increasingly turning to the use of environmentally friendly materials in order to meet the sustainable aspect required by modern infrastructures. Consequently, for the last two decades, the expansion of this concept, and the increasing global warming have raised concerns on the extensive use of Portland cement due to the high amount of carbon dioxide gas associated with its production. The development of geopolymer concretes offers promising signs for a change in...
Show moreThe construction industry is increasingly turning to the use of environmentally friendly materials in order to meet the sustainable aspect required by modern infrastructures. Consequently, for the last two decades, the expansion of this concept, and the increasing global warming have raised concerns on the extensive use of Portland cement due to the high amount of carbon dioxide gas associated with its production. The development of geopolymer concretes offers promising signs for a change in the way of producing concrete. However, to seriously consider geopolymer binders as an alternative to ordinary Portland cement, the durability of this new material should be evaluated in any comparative analysis. The main purpose of this study was to evaluate the durability characteristics of low calcium fly ash-based geopolymer concretes subjected to the marine environment, compared to ordinary Portland cement concrete with similar exposure. To achieve this goal, 8 molar geopolymer, 14 molar geopolymer and ordinary Portland cement concrete mixes were prepared and tested for exposure in seawater. Compressive strengths in the range of 2900 to 8700 psi (20-60 MPa) were obtained. The corrosion resistance performance of steel-reinforced concrete beams, made of these mixes, was also studied, using an accelerated electrochemical method, with submergence in salt water. The test results indicated that the geopolymer concrete showed excellent resistance to chloride attack, with longer time to corrosion cracking, compared to ordinary Portland cement concrete.
Show less - Date Issued
- 2011
- PURL
- http://purl.flvc.org/FAU/3170960
- Subject Headings
- Reinforced concrete, Corrosion, Testing, Reinforced concrete construction, Concrete, Mixing, Quality control, Environmental chemistry, Industrial applications, Polymer composites
- Format
- Document (PDF)
- Title
- Minimization of overall person delay at light rail transit crossings on congested urban arterials.
- Creator
- Mitrovic, Nikola, College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
This study describes analytical model as one innovative way to simulate Light Rail Transit (LRT) operations and calculate vehicular, transit and person delays at LRT crossings through Microsoft Excel. Analytical model emulates LRT trajectories from field and use these trajectories to clearly define train and car phases through Visual Basic for Applications (VBA) logic, which is part of analytical model. Simulation of train trajectories and calculations of delays were done for different LRT...
Show moreThis study describes analytical model as one innovative way to simulate Light Rail Transit (LRT) operations and calculate vehicular, transit and person delays at LRT crossings through Microsoft Excel. Analytical model emulates LRT trajectories from field and use these trajectories to clearly define train and car phases through Visual Basic for Applications (VBA) logic, which is part of analytical model. Simulation of train trajectories and calculations of delays were done for different LRT strategies and estimated roadway condition, Testing and validation of analytical model were performed in one case study in Salt Lake City (UT). Results show that analytical model is capable of emulating LRT trajectories and estimating delay at isolated LRT crossing. However, analytical model is not capable of simulating different train strategies at two or more LRT crossings, at the same time. Finally, extracted strategy provides savings from $100.000 to $200.000 in study area, on annual basis for projected year.
Show less - Date Issued
- 2011
- PURL
- http://purl.flvc.org/FAU/3171724
- Subject Headings
- Railroads, Local and light, Evaluation, Railroad crossings, Evaluation, Street-railroads, Evaluation, Roads, Interchanges and intersections, Traffic congestion, Causes
- Format
- Document (PDF)
- Title
- Operational and environmental comparisons between left-turn bypass, diverging flow and displaced left-turn intersection designs.
- Creator
- Olarte, Claudia, College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
The rapidly and significantly growth of the population in the United States has caused expansion of the urban areas to accommodate more residential facilities.. Thus, the demand for more efficient intersection designs is a high priority, as wasted fuel and travel time increases each year. A new method to solve the congestion issue is the creation of unconventional arterial intersection designs (UAID). The objective of this study is to compare the operational and environmental performance of...
Show moreThe rapidly and significantly growth of the population in the United States has caused expansion of the urban areas to accommodate more residential facilities.. Thus, the demand for more efficient intersection designs is a high priority, as wasted fuel and travel time increases each year. A new method to solve the congestion issue is the creation of unconventional arterial intersection designs (UAID). The objective of this study is to compare the operational and environmental performance of three UAIDs called Left-turn Bypass, Diverging Flow, and Displaced Left-turn intersections. This study will evaluate the UAIDs in the isolated manner and then compare the intersections in a network using an existing corridor in the state of Florida. The microscopic simulation platform VISSIM v. 5.10 will be used to test different scenarios. The results indicated that the Displaced Left-turn consistently reports better results for average delay of less than 20 seconds per vehicle.
Show less - Date Issued
- 2011
- PURL
- http://purl.flvc.org/FAU/3172428
- Subject Headings
- Traffic engineering, Streets, Design, Traffic signs and signals, Roads, Interchanges and intersections
- Format
- Document (PDF)
- Title
- Strength and toughness of HDPE fiber reinforced aggregate concrete as a sustainable construction material.
- Creator
- Numa, Roody., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
An experimental study was conducted on the strength and toughness characteristics of concrete made from recycled aggregate, cement and fly ash reinforced with reclaimed high density polyethylene plastic (HDPE) fibers. The objectives of the investigation were: (1) to evaluate the performance of a sustainable concrete containing up to 90% recycled materials; (2) to determine the variation of strength and toughness with a Fiber Factor incorporating length, width and amount of HDPE fibers; (3) to...
Show moreAn experimental study was conducted on the strength and toughness characteristics of concrete made from recycled aggregate, cement and fly ash reinforced with reclaimed high density polyethylene plastic (HDPE) fibers. The objectives of the investigation were: (1) to evaluate the performance of a sustainable concrete containing up to 90% recycled materials; (2) to determine the variation of strength and toughness with a Fiber Factor incorporating length, width and amount of HDPE fibers; (3) to identify the best performing mix design based on tensile strength and toughness and (4) to provide some guidelines for the use of this sustainable composite in Civil Engineering construction. The results showed that the HDPE fiber reinforcements did not improve the compressive strength of the mixture. However, HDPE fibers improved the ductility and toughness which may be beneficial for structural and pavement applications.
Show less - Date Issued
- 2011
- PURL
- http://purl.flvc.org/FAU/3172430
- Subject Headings
- Fibrous composites, Cement composites, Reinforced concrete, Fiber, Conposite-reinforced concrete
- Format
- Document (PDF)
- Title
- Numerical simulation and prediction of loads in marine current turbine full-scale rotor blades.
- Creator
- Senat, Junior., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
Marine current turbines are submerged structures and subjected to loading conditions from both the currents and wave effects. The associated phenomena posed significant challenge to the analyses of the loading response of the rotor blades and practical limitations in terms of device location and operational envelopes. The effect of waves on marine current turbines can contribute to the change of flow field and pressure field around the rotor and hence changes the fluid forces on the rotor....
Show moreMarine current turbines are submerged structures and subjected to loading conditions from both the currents and wave effects. The associated phenomena posed significant challenge to the analyses of the loading response of the rotor blades and practical limitations in terms of device location and operational envelopes. The effect of waves on marine current turbines can contribute to the change of flow field and pressure field around the rotor and hence changes the fluid forces on the rotor. However, the effect of the waves on the rotor depends on the magnitude and direction of flow velocity that is induced by the waves. An analysis is presented for predicting the torque, thrust, and bending moments resulting from the wave-current interactions at the root of rotor blades in a horizontal axis marine current turbine using the blade element-momentum (BEM) theory combined with linear wave theory. Parametric studies are carried out to better understand the influence of important parameters , which include wave height, wave frequency, and tip-speed ratio on the performance of the rotor. The periodic loading on the blade due to the steady spatial variation of current speeds over the rotor swept area is determined by a limited number of parameters, including Reynolds number, lift and drag coefficients, thrust and torque coefficients, and power coefficient. The results established that the BEM theory combined with linear wave theory can be used to analyze the wavecurrent interactions in full-scale marine current turbine. The power and thrust coefficients can be analyzed effectively using the numerical BEM theory in conjunction with corrections to the tip loss coefficient and 3D effects., It has been found both thrust and torque increase as the current speed increases, and in longer waves the torque is relatively sensitive to the variation of wave height. Both in-plane and out-of-plane bending moments fluctuate significantly and can be predicted by linear wave theory with blade element-momentum theory.
Show less - Date Issued
- 2011
- PURL
- http://purl.flvc.org/FAU/3172695
- Subject Headings
- Marine turbines, Mathematical models, Structural dynamics, Fluid dynamics, Rotors, Design and construction
- Format
- Document (PDF)
- Title
- Modeling and simulation on the yard trailers deployment in the maritime container terminal.
- Creator
- Zhao, Yueqiong, College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
In recent years, there has been an exponential increase in container volume shipment within intermodal transportation systems. Container terminals as part of the global port system represent important hubs within this intermodal transportation system. Thus, the need to improve the operational efficiency is the most important issue for container terminals from an economic standpoint. Moreover, intermodal transportation systems, ports and inland transport facilities should all be integrated...
Show moreIn recent years, there has been an exponential increase in container volume shipment within intermodal transportation systems. Container terminals as part of the global port system represent important hubs within this intermodal transportation system. Thus, the need to improve the operational efficiency is the most important issue for container terminals from an economic standpoint. Moreover, intermodal transportation systems, ports and inland transport facilities should all be integrated into one coordinated plan. More specifically, a method to schedule different types of handling equipment in an integrated way within a container terminal is a popular topic for researchers. However, not many researchers have addresses this topic in relationship to the simulation aspect which will test feasible solutions under real container terminal environment parameters. In order to increase the efficiency of operations, the development of mathematical models and algorithms is critical in finding the best feasible solution. The objective of this study is to evaluate the feasible solution to find the proper number of Yard Trailers (YTs) with the minimal cost for the container terminals. This study uses the Dynamic YTs operation's method as a background for modeling. A mathematical model with various constraints related to the integrated operations among the different types of handling equipment is formulated. This model takes into consideration both serving time of quay cranes and yard cranes, and cost reduction strategies by decreasing use of YTs with the specific objective of minimum total cost including utilization of YTs and vessel berthing. In addition, a heuristic algorithm combined with Monte Carlo Method and Brute-Force Search are employed. The early Stage Technique of Monte Carlo method is proposed to generate vast random numbers to replicate simulation for real cases., The Brute-Force Search is used for identifying all potential cases specific to the conditions of this study. Some preliminary numerical test results suggest that this method is good for use in conjunction with simulation of container terminal operation. The expected outcome of this research is a solution to obtain the proper number of YTs for transporting containers with a minimum cost; thus, improving the operational efficiency in a container terminal.
Show less - Date Issued
- 2011
- PURL
- http://purl.flvc.org/FAU/3174315
- Subject Headings
- Marine terminals, Computer programs, Computer algorithms, Materials management, Warehouses, Management, Transportation engineering, Freight and freightage
- Format
- Document (PDF)
- Title
- Reliability-based fatigue design of marine current turbine rotor blades.
- Creator
- Hurley, Shaun., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
The study presents a reliability-based fatigue life prediction model for the ocean current turbine rotor blades. The numerically simulated bending moment ranges based on the measured current velocities off the Southeast coast line of Florida over a one month period are used to reflect the short-term distribution of the bending moment ranges for an idealized marine current turbine rotor blade. The 2-parameter Weibull distribution is used to fit the short-term distribution and then used to...
Show moreThe study presents a reliability-based fatigue life prediction model for the ocean current turbine rotor blades. The numerically simulated bending moment ranges based on the measured current velocities off the Southeast coast line of Florida over a one month period are used to reflect the short-term distribution of the bending moment ranges for an idealized marine current turbine rotor blade. The 2-parameter Weibull distribution is used to fit the short-term distribution and then used to obtain the long-term distribution over the design life. The long-term distribution is then used to determine the number of cycles for any given bending moment range. The published laboratory test data in the form of an ε-N curve is used in conjunction with the long-term distribution of the bending moment ranges in the prediction of the fatigue failure of the rotor blade using Miner's rule. The first-order reliability method is used in order to determine the reliability index for a given section modulus over a given design life. The results of reliability analysis are then used to calibrate the partial safety factors for load and resistance.
Show less - Date Issued
- 2011
- PURL
- http://purl.flvc.org/FAU/3183123
- Subject Headings
- Turbines, Blades, Materials, Fatigue, Marine turbines, Mathematical models, Composite materials, Mathematical models, Structural dynamics
- Format
- Document (PDF)
- Title
- Treatment of landfill leachate via advanced oxidation.
- Creator
- McBarnette, Andrâe., College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
- Abstract/Description
-
A landfill is in a reserved space on land used for the disposal of refuse by utilizing the principles of engineering to confine the refuse to the smallest practical area to prevent the creation of nuisances to public health or safety (Andersen et al. 1967). However, because landfills are open to the atmosphere, rainfall can saturate them, resulting in a liquid called leachate. Leachate generated within the landfill contains suspended solids, soluble components of the waste and by-products...
Show moreA landfill is in a reserved space on land used for the disposal of refuse by utilizing the principles of engineering to confine the refuse to the smallest practical area to prevent the creation of nuisances to public health or safety (Andersen et al. 1967). However, because landfills are open to the atmosphere, rainfall can saturate them, resulting in a liquid called leachate. Leachate generated within the landfill contains suspended solids, soluble components of the waste and by-products from the degradation of the waste by various micro-organisms. Treatment of leachate is an emerging area of need. In this manuscript the main purpose is to investigate a laboratory scale batch reactor that is able to detoxify and treat leachate by using an advanced oxidation process (i.e. TiO2). Based on the results obtained from this ground breaking research, it appears that the process investigate has the potential to radically change the way landfill leachate is treated. Scale up may provide direction that can be used to improve the efficiency of the different stages of toxicity of leachate during the entire life of a landfill.
Show less - Date Issued
- 2011
- PURL
- http://purl.flvc.org/FAU/3318665
- Subject Headings
- Sanitary landfills, Leaching, Environmental aspects, Refuse and refuse disposal, Environmental aspects, Integrated solid waste management, Water, Purification, Oxidation
- Format
- Document (PDF)