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Electronic Theses and Dissertations

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Full-Text Articles in Civil and Environmental Engineering

A Joint Econometric Approach For Modeling Crash Counts By Collision Type, Tanmoy Bhowmik Jan 2018

A Joint Econometric Approach For Modeling Crash Counts By Collision Type, Tanmoy Bhowmik

Electronic Theses and Dissertations

In recent years, there is growing recognition that common unobserved factors that influence crash frequency by one attribute level are also likely to influence crash frequency by other attribute levels. The most common approach employed to address the potential unobserved heterogeneity in safety literature is the development of multivariate crash frequency models. The current study proposes an alternative joint econometric framework to accommodate for the presence of unobserved heterogeneity – referred to as joint negative binomial-multinomial logit fractional split (NB-MNLFS) model. Furthermore, the study undertakes a first of its kind comparison exercise between the most commonly used multivariate model (multivariate …


Evaluating The Integration Of Chlorine Dioxide Into A Coagulation, Sedimentation, And Filtration Process Treating Surface Water, Martin Coleman Jan 2018

Evaluating The Integration Of Chlorine Dioxide Into A Coagulation, Sedimentation, And Filtration Process Treating Surface Water, Martin Coleman

Electronic Theses and Dissertations

Methods of optimizing the coagulation, flocculation, sedimentation, and filtration (CSF) process at a conventional surface water treatment plant (WTP) were conducted to investigate opportunities for the reduction of disinfection by-product (DBP) precursor material. The research had two primary components: (1) optimize coagulant dosage and associated operating pH and (2) investigate pretreatment oxidation with chlorine dioxide (ClO2) and potassium permanganate (KMnO4). To accomplish the first component, jar tests were conducted at various pH and aluminum sulfate (alum) dosages to model current and potential treatment conditions during the CSF process at a WTP. Isopleths were developed to examine the removal efficiencies of …


Harmful Algal Bloom Mitigating Using Recycled Concrete Aggregate Coated With Fixed-Quat., Ikenna Ezeodurukwe Jan 2018

Harmful Algal Bloom Mitigating Using Recycled Concrete Aggregate Coated With Fixed-Quat., Ikenna Ezeodurukwe

Electronic Theses and Dissertations

Human activities generate surplus nutrients which may lead to algal bloom events in water resources along with serious ecological problems and thus substantial economic losses. Particularly, harmful algal blooms (HABs) represent toxic cyanobacterial blooms which produce cyanotoxins. The primary concerns of HABs are the exposures to a wide variety of cyanotoxins via ingestion of contaminated drinking water, inhalation during recreational activities, and consumption of contaminated fish and shellfish. However, conventional physical and chemical methods are not always possible to efficiently handle these HABs events. It is urgent to develop viable and rapid solutions to control HABs in field and mitigate …


Understanding How, Where And How Much Freight Flows Using 2012 Commodity Flow Survey Data, Nowreen Keya Jan 2018

Understanding How, Where And How Much Freight Flows Using 2012 Commodity Flow Survey Data, Nowreen Keya

Electronic Theses and Dissertations

In recent years, with increased economic globalization, growing e-commerce and internet based shopping, freight movement patterns are undergoing a transformative change. The shipment size distribution is moving towards a higher share of smaller size shipments affecting transportation mode and vehicle type requirements. In addition, freight transportation mode is closely affected by the destination location (and its attributes). In our dissertation, we contribute to freight research by developing a comprehensive framework to examine the how, where and how much freight flows in US. Specifically, we study the following dimensions of freight flow: (1) transportation mode, (2) mode and shipment weight choice …


Treatment Of Leachate Organic Matter Through Sunlight Driven Processes, Duncan Lozinski Jan 2018

Treatment Of Leachate Organic Matter Through Sunlight Driven Processes, Duncan Lozinski

Electronic Theses and Dissertations

The ability to manage leachate during post-closure care (PCC) of a landfill may be increasingly difficult as leachate organic matter (LOM) becomes recalcitrant when a landfill ages, requiring advanced and costly treatment technologies. This research investigated the ability to treat LOM through sunlight driven processes, with a focus on photolysis, to provide insight to landfill owners and operators on the potential of wetlands treatment as a means for reducing long-term risks and costs associated with leachate treatment during PCC. The study was completed in eight batch tests, where leachate was exposed to natural sunlight in central Florida for a period …


Performance Predication Model For Advance Traffic Control System (Atcs) Using Field Data, Masood Mirza Jan 2018

Performance Predication Model For Advance Traffic Control System (Atcs) Using Field Data, Masood Mirza

Electronic Theses and Dissertations

Reductions in capital expenditure revenues have created greater demands from users for quality service from existing facilities at lower costs forcing agencies to evaluate the performance of projects in more comprehensive and "greener" ways. The use of Adaptive Traffic Controls Systems (ATCS) is a step in the right direction by enabling practitioners and engineers to develop and implement traffic optimization strategies to achieve greater capacity out of the existing systems by optimizing traffic signal based on real time traffic demands and flow pattern. However, the industry is lagging in developing modeling tools for the ATCS which can predict the changes …


Investigation Of Factors Contributing To Fog-Related Single Vehicle Crashes, Jiazheng Zhu Jan 2018

Investigation Of Factors Contributing To Fog-Related Single Vehicle Crashes, Jiazheng Zhu

Electronic Theses and Dissertations

Fog-related crashes continue to be one of the most serious traffic safety problems in Florida. Based on the historical crash data, we found that single-vehicle crashes have the highest severity among all types of crashes under fog conditions. This study first analyzed the contributing factors of the fog-related single-vehicle crashes' (i.e., off road/rollover/other) severity in Florida from 2011 to 2014 using association rules mining. The results show that lane departure distracted driving, wet road surface, and dark without road light are the main contributing factors to severe fog-related single vehicle crashes. Some suggested countermeasures were also provided to reduce the …


Hierarchical Corridor Safety Analysis Using Multiple Approaches, Saif Alarifi Jan 2018

Hierarchical Corridor Safety Analysis Using Multiple Approaches, Saif Alarifi

Electronic Theses and Dissertations

Traffic crashes are a major cause of concern globally. Extensive efforts from transportation professionals have been made to investigate new methods to identify the contributing factors to crashes at various locations on the road network. Corridors, among other road network's components, play a vital role in moving people and goods between primary zones in different areas, and the safety and operational improvements of them have been the focus of many studies since they carry the most traffic on the road network. Corridors contain mainly intersections and segments, and previous corridor studies have focused on a sole type of road entity. …


Investigating And Facilitating The Transferability Of Safety Performance Functions, Ahmed Tarek Ahmed Farid Jan 2018

Investigating And Facilitating The Transferability Of Safety Performance Functions, Ahmed Tarek Ahmed Farid

Electronic Theses and Dissertations

Safety performance functions (SPFs) are essential analytical tools in the road safety field. The SPFs are statistical regression models used to predict crash counts by roadway facility type, crash type and severity. The national Highway Safety Manual (HSM) is a generic guidebook used for road safety evaluation and enhancement. In it, default SPFs, developed using negative binomial (NB) regression, are provided for multiple facility types and crash categories. Roadway agencies, whether public or private, may opt to not invest their resources in data collection and processing to develop own localized SPFs. Instead, the agencies may adopt the HSM's. However, the …


A Decision Support Model For Autonomous Trucks Strategies, Ahmad Mohamed Jan 2018

A Decision Support Model For Autonomous Trucks Strategies, Ahmad Mohamed

Electronic Theses and Dissertations

We examined the potential to improve the movement of freight using Truck Platooning Lane strategies on limited access highways in the State of Florida. In the First part of this research, we investigated the potential benefits from dedicating one lane from existing lanes for autonomous trucks only. In this regard, a general framework tool was developed to evaluate and compare different measurements (e.g., travel tim and emissions) to better assist decision makers to determine the most effective freight transportation strategy. Additionally, the travel time, level of service and emissions on Florida Strategic Intermodal System (SIS) were systematically analyzed using a …


Cost And Environmental Impacts Of Leachate Nitrogen/Phosphorus Management Approaches, Alaa Alanezi Jan 2018

Cost And Environmental Impacts Of Leachate Nitrogen/Phosphorus Management Approaches, Alaa Alanezi

Electronic Theses and Dissertations

Landfill leachate is a challenging wastewater to discharge into municipal wastewater treatment plants (WWTPs), the most common approach for leachate management, due to the presence of contaminants that may affect the performance of the treatment plant. Treatment, disposal, and transportation of leachate are expensive and therefore a concern. Currently, sidestream treatment is becoming increasingly common in WWTPs prior to returning the liquid to the plant influent. For this research, a new treatment scheme is introduced combining centrate and leachate to reduce contaminants, recover phosphorous and nitrogen through struvite precipitation, and reduce energy requirements through anaerobic ammonium oxidation (Anammox). By combining …


Disinfection By-Product Reduction Study Of A Small Central Florida Public Water System, Paul Staubus Jan 2018

Disinfection By-Product Reduction Study Of A Small Central Florida Public Water System, Paul Staubus

Electronic Theses and Dissertations

The disinfection of water for potabilization has proven to be one of the most significant public achievements of the 20th century. Although chemical disinfectants are successfully utilized to inactivate acute pathogenic organisms, they may react with natural organic matter (NOM) to produce potentially-harmful disinfection by-products (DBPs). As a result, the United States Environmental Protection Agency regulates DBPs such as total trihalomethanes (TTHMs) and haloacetic acids (HAAs). The research herein is focused on the formation, removal, and control of TTHMs and HAAs in a small public water system (PWS) in Polk County, Florida (County). Pilot-scale tests were implemented to determine the …


Explore Contributing Geometric Factors And Built-Environment On Bicycle Activity And Safety At Intersections, Scott Castro Jan 2018

Explore Contributing Geometric Factors And Built-Environment On Bicycle Activity And Safety At Intersections, Scott Castro

Electronic Theses and Dissertations

This study attempts to explore all factors associated with bicycle motor-vehicle crashes at intersections in order to improve bicycle safety and bicycle activity. Factors such as exposure (bicycle and vehicle volumes), existing facilities (bike lanes, sidewalks, shared-use paths), geometric design (# of lanes, speed limit, medians, legs, roadway conditions), and land-use were collected and evaluated using Poisson, Zero-Inflated Poisson, and Negative Binomial models in SAS 9.4 software. Increasing the bicycle travel mode can have positive lasting effects on personal health, the environment, and improve traffic conditions. Deterrents that keep users from riding bicycles more are the lack of facilities and …


Accommodating Exogenous Variable And Decision Rule Heterogeneity In Discrete Choice Models: Application To Bicyclist Route Choice, Bibhas Dey Jan 2018

Accommodating Exogenous Variable And Decision Rule Heterogeneity In Discrete Choice Models: Application To Bicyclist Route Choice, Bibhas Dey

Electronic Theses and Dissertations

The thesis contributes to our understanding of incorporating heterogeneity in discrete choice models with respect to exogenous variables and decision rules. Specifically, we evaluate latent segmentation based mixed models that allow for segmenting population based on decision rules while also incorporating unobserved heterogeneity within the segment level decision rule models. In our analysis, we choose to consider the random utility framework along with random regret minimization approach. Further, instead of assuming the number of segments (as 2), we conduct an exhaustive exploration with multiple segments across the two decision rules. Within each segment we also allow for unobserved heterogeneity. The …


Understanding Crisis Communication And Mobility Resilience During Disasters From Social Media, Kamol Roy Jan 2018

Understanding Crisis Communication And Mobility Resilience During Disasters From Social Media, Kamol Roy

Electronic Theses and Dissertations

Rapid communication during extreme events is one of the critical aspects of successful disaster management strategies. Due to their ubiquitous nature, social media platforms offer a unique opportunity for crisis communication. Moreover, social media usage on GPS enabled devices such as smartphones allow us to collect human movement data which can help understanding mobility during a disaster. This study leverages social media (Twitter) data to understand the effectiveness of social media-based communication and the resilience of human mobility during a disaster. This thesis has two major contributions. First, about 52.5 million tweets related to hurricane Sandy are analyzed to assess …


Assessing The Impact Of Multi-Variate Steering-Rate Vehicle Control On Driver Performance In A Simulation Framework, Michael Xynidis Jan 2018

Assessing The Impact Of Multi-Variate Steering-Rate Vehicle Control On Driver Performance In A Simulation Framework, Michael Xynidis

Electronic Theses and Dissertations

When a driver turns a steering-wheel, he or she normally expects the vehicle's steering system to communicate an equivalent amount of signal to the road-wheels. This relationship is linear and occurs regardless of the steering-wheel's position within its rotational travel. The linear steering paradigm in passenger vehicles has gone largely unchanged since mass production of passenger vehicles began in 1901. However, as more electronically-controlled steering systems appear in conjunction with development of autonomous steering functions in vehicles, an opportunity to advance the existing steering paradigms arises. The following framework takes a human-factors approach toward examining and evaluating alternative steering systems …


Development And Application Of An Optimization Approach For Cost-Effective Deployment Of Advanced Wrong-Way Driving Countermeasures, Adrian Sandt Jan 2018

Development And Application Of An Optimization Approach For Cost-Effective Deployment Of Advanced Wrong-Way Driving Countermeasures, Adrian Sandt

Electronic Theses and Dissertations

Wrong-way driving (WWD) is a dangerous behavior, especially on high-speed divided highways. The nature of WWD crashes makes it difficult for agencies to combat them effectively. Advanced WWD countermeasures equipped with flashing lights, detection devices, and cameras can significantly reduce WWD. However, these countermeasures' high costs mean that agencies often cannot deploy them at all exit ramps. To help agencies identify the most cost-effective deployment locations for advanced WWD countermeasures, an innovative WWD countermeasure optimization approach was developed. This approach consists of a WWD hotspots model and a WWD countermeasures optimization algorithm. The WWD hotspots model uses non-crash WWD events, …


A Holistic Analysis Of The Long-Term Challenges & Potential Benefits Of The Green Roof, Solar Pv Roofing, And Gripv Roofing Markets In Orlando, Florida, Carolina Kelly Jan 2018

A Holistic Analysis Of The Long-Term Challenges & Potential Benefits Of The Green Roof, Solar Pv Roofing, And Gripv Roofing Markets In Orlando, Florida, Carolina Kelly

Electronic Theses and Dissertations

Green roofs and roof-mounted solar PV arrays have a wide range of environmental and economic benefits, including significantly longer roof lifetimes, reductions in urban runoff, mitigation of the urban heat island (UHI) effect, reduced electricity demand and energy dependence, and/or reduced emissions of greenhouse gases (GHGs) and other harmful pollutants from the electricity generation sector. Consequently, green roofs and solar panels have both become increasingly popular worldwide, and promising new research has emerged for their potential combination in Green Roof Integrated Photovoltaic (GRIPV) roofing applications. However, due to policy resistance, these alternatives still have marginal market shares in the U.S., …


Seismic Response Of Moment Resisting Frames Coupled With Rocking Walls, Mehrdad Aghagholizadeh Jan 2018

Seismic Response Of Moment Resisting Frames Coupled With Rocking Walls, Mehrdad Aghagholizadeh

Electronic Theses and Dissertations

This study investigates the inelastic response of yielding structures coupled with rocking walls. This topic is of major significance in the design of tall moment-resisting buildings, since during recent major earthquakes several tall, moment-resisting frames that had been designed in an accordance to the existing seismic code provisions, exhibited a weak-story failure. Utilization of this structural system can help reducing maximum story drifts, prevents weak story failure and minimize residual deformation of the structure. This study first examines different configurations of both stepping rocking walls and pinned rocking walls that have been reported in the literature. Next, effect of additional …


Seepage And Stability Analysis Of The Earth Dams Under Drawdown Conditions By Using The Finite Element Method, Salama Al-Labban Jan 2018

Seepage And Stability Analysis Of The Earth Dams Under Drawdown Conditions By Using The Finite Element Method, Salama Al-Labban

Electronic Theses and Dissertations

One of the major concerns in the behavior of an earth dam is the change in the exit gradient and the impact on the slope stability under drawdown conditions. Drawdown can cause increased seepage forces on the upstream slope which may result in the movement of soil particles in the flow direction and cause erosion problems. In this research, a numerical approach, based on the finite element method (FEM) is used to analyze the seepage through the dam and its foundation to study exit gradients and slope stability under both steady-state and transient conditions. The results show that a central …


Development Of Soil Compressibility Prediction Models, Scott Kirts Jan 2018

Development Of Soil Compressibility Prediction Models, Scott Kirts

Electronic Theses and Dissertations

The magnitude of the overall settlement depends on several variables such as the Compression Index, Cc, and Recompression Index, Cr, which are determined by a consolidation test; however, the test is time consuming and labor intensive. Correlations have been developed to approximate these compressibility indexes. In this study, a data driven approach has been employed in order to estimate Cc and Cr. Support Vector Machines classification is used to determine the number of distinct models to be developed. The statistical models are built through a forward selection stepwise regression procedure. Ten variables were used, including the moisture content (w), initial …


Evaluation And Augmentation Of Traffic Data From Private Sector And Bluetooth Detection System On Arterials, Yaobang Gong Jan 2018

Evaluation And Augmentation Of Traffic Data From Private Sector And Bluetooth Detection System On Arterials, Yaobang Gong

Electronic Theses and Dissertations

Traffic data are essential for public agencies to monitor the traffic condition of the roadway network in real-time. Recently, public agencies have implemented Bluetooth Detection Systems (BDS) on arterials to collect traffic data and purchased data directly from private sector vendors. However, the quality and reliability of the aforementioned two data sources are subject to rigorous evaluation. The thesis presents a study utilizing high-resolution GPS trajectories to evaluate data from HERE, one of the private sector data vendors, and BDS of arterial corridors in Orlando, Florida. The results showed that the accuracy and reliability of BDS data are better than …


Volumetric Three-Component Velocimetry Two-Phase Flow Measurements Of Sediment Suspension Under Regular Plunging Waves, Deryn Ann Beck Jan 2018

Volumetric Three-Component Velocimetry Two-Phase Flow Measurements Of Sediment Suspension Under Regular Plunging Waves, Deryn Ann Beck

Electronic Theses and Dissertations

Breaking waves suspend and transport large amounts of sediment particles in the surf zone. Two important aspects of the problem are the mechanism of sediment suspension and the distribution of the suspended sediment. One approach to solving this problem is to measure the sediment particles’ position and movement simultaneously with the characteristics of the flow field. Previous studies have found that sediment suspension events are related to a number of flow parameters including the vertical velocity, vorticity, horizontal velocity, turbulent kinetic energy, total shear stress, and turbulent shear stress. The objective of this study was to design and conduct an …


Modeling Water Availability, Risk And Resilience In A Semi-Arid Basin In Southern Africa, Esther N. Mosase Jan 2018

Modeling Water Availability, Risk And Resilience In A Semi-Arid Basin In Southern Africa, Esther N. Mosase

Electronic Theses and Dissertations

Climate variability need to be incorporated into the management and planning of water resources, particularly in arid and semi-arid regions, where water availability is more sensitive to rainfall and air temperature. This study used modified Man-Kendall trend analysis test and ArcGIS to process data. Annual means of rainfall, minimum temperature and maximum temperature in the Limpopo River Basin (LRB) varied between 160 and 1109 mm, 8 °C to 20 °C and 23 °C to 32 °C respectively. The spatial pattern is generally increasing from west to east for rainfall and minimum temperature while maximum temperature increases from south to north …


Repairable Precast Buildings And Bridges, Abdullah Boudaqa Jan 2018

Repairable Precast Buildings And Bridges, Abdullah Boudaqa

Electronic Theses and Dissertations

A new moment-resisting precast connection is developed in the present work through experimental and analytical studies to accelerate construction of bridges and buildings, to improve their seismic performance, and to quickly repair them through replacement of exposed reinforcement. The new precast joint detailing incorporates (1) detachable external reinforcing steel bars restrained against buckling, which is referred to as buckling restrained reinforcement (BRR), to develop plastic bending moments, (2) a steel pipe connecting the precast members through a pin connection to resist plastic shear forces, and (3) detachable mechanical bar splices to assemble and disassemble BRR at any time specifically after …


Compaction Testing Of Granular Material, Jason Jerome Weber Jan 2018

Compaction Testing Of Granular Material, Jason Jerome Weber

Electronic Theses and Dissertations

The South Dakota Department of Transportation SDDOT uses the Ohio Highway Department’s Typical Moisture Density Curves for preforming compaction quality control on granular soil materials in junction with standard moisture density relations. The SDDOT also uses the Nuclear Density Gauge NDG, Sand Cone, and Rubber Balloon methods to conduct in-situ density tests. Compaction quality control of recycled pavements is conducted using test strips. The test strip method works well for large areas but becomes problematic for small areas. The ODOT Materials Manual states “Moisture-Density proctor curves and controls were originally developed to be used on cohesive (clays and silts) soils. …


Evaluation Of The Moisture-Induced Damage Potential Of Asphalt Mixes And Asphalt Binder-Aggregate Systems, Rajan Acharya Jan 2018

Evaluation Of The Moisture-Induced Damage Potential Of Asphalt Mixes And Asphalt Binder-Aggregate Systems, Rajan Acharya

Electronic Theses and Dissertations

The current thesis presents the findings of a study conducted on asphalt mixes to evaluate their moisture-induced damage potential through testing of the plant produced asphalt mixes in South Dakota using local aggregates and commonly used asphalt binders. The moisture-induced damage potentials of the asphalt mixes were evaluated by conducting tensile strength ratio (TSR) and modified Semicircular Bend (SCB) tests. The effect of moisture on asphalt binder-aggregate adhesion was evaluated by conducting binder bond strength (BBS) test on binder-aggregate systems. The asphalt mixes tested in this study included a hot mix asphalt (HMA) containing hydrated lime (1% by the weight …


Comparison Of Historical Precipitation For Aberdeen, Ipswich, And Eureka, South Dakota, Uday Singh Kshatriya Jan 2018

Comparison Of Historical Precipitation For Aberdeen, Ipswich, And Eureka, South Dakota, Uday Singh Kshatriya

Electronic Theses and Dissertations

The availability of water resources varies from time to time with the climate conditions. Keeping track of climate conditions would eventually benefit for the future predictions. The objective of this research was to compare and contrast the climate especially for Aberdeen, Ipswich and Eureka, South Dakota utilizing the historical monthly precipitation records and to develop the techniques that are reliable to estimate the missing data. For these necessary statistical analyses were performed using the monthly precipitation data from High Plains Regional Climate Center (HPRCC) for the annual and 8-Year periods for Aberdeen, Ipswich and Eureka, South Dakota. 63 water years …


Methodology For Load Rating Double-Tee Girder Bridges, Sandip Rimal Jan 2018

Methodology For Load Rating Double-Tee Girder Bridges, Sandip Rimal

Electronic Theses and Dissertations

The most common type of bridge on South Dakota (SD) local roads is precast prestressed double-tee (DT) girders. More than 700 DT bridges are currently in-service in SD. Structural detailing, aging, traffic volume, and environmental conditions affect the structural performance, integrity, and capacity of DT bridges. When a bridge is affected by one or more of the aforementioned parameters, the estimation of the bridge safe live loads is necessary to ensure the safety of the traveling public and to prevent excessive bridge damage and collapse. Load rating of damaged bridges is challenging mainly because of a lack of information regarding …


Laboratory Evaluation Of Internal And External Nutrient Removal To Control Algal Bloom In Eutrophic Lakes, Sepideh Sadeghi Jan 2018

Laboratory Evaluation Of Internal And External Nutrient Removal To Control Algal Bloom In Eutrophic Lakes, Sepideh Sadeghi

Electronic Theses and Dissertations

Eutrophication is one of the most widespread water quality problems in lakes and reservoirs. Frequent cyanobacterial blooms resulting from eutrophication can greatly damage aquatic ecosystems and pose a high risk to human health. Phosphorus (P) and nitrogen (N) are the major causes for eutrophic conditions and can enter to the aquatic ecosystem via different sources. The combination of phosphorus precipitation and sediment capping are promising technologies to minimize internal P loading and control harmful algal blooms in eutrophic lakes. Denitrification bioreactors have emerged as an important edge-of-field treatment technology to reduce nitrate-nitrogen loads from external sources. The objective of this …