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Full-Text Articles in Engineering
Evaluation Of Crash Modification Factors And Functions Including Time Trends At Intersections, Jung-Han Wang
Evaluation Of Crash Modification Factors And Functions Including Time Trends At Intersections, Jung-Han Wang
Electronic Theses and Dissertations
Traffic demand has increased as population increased. The US population reached 313,914,040 in 2012 (US Census Bureau, 2015). Increased travel demand may have potential impact on roadway safety and the operational characteristics of roadways. Total crashes and injury crashes at intersections accounted for 40% and 44% of traffic crashes, respectively, on US roadways in 2007 according to the Intersection Safety Issue Brief (FHWA, 2009). Traffic researchers and engineers have developed a quantitative measure of the safety effectiveness of treatments in the form of crash modification factors (CMF). Based on CMFs from multiple studies, the Highway Safety Manual (HSM) Part D …
Investigation Of Infrared Thermography For Subsurface Damage Detection Of Concrete Structures, Shuhei Hiasa
Investigation Of Infrared Thermography For Subsurface Damage Detection Of Concrete Structures, Shuhei Hiasa
Electronic Theses and Dissertations
Deterioration of road infrastructure arises from aging and various other factors. Consequently, inspection and maintenance have been a serious worldwide problem. In the United States, degradation of concrete bridge decks is a widespread problem among several bridge components. In order to prevent the impending degradation of bridges, periodic inspection and proper maintenance are indispensable. However, the transportation system faces unprecedented challenges because the number of aging bridges is increasing under limited resources, both in terms of budget and personnel. Therefore, innovative technologies and processes that enable bridge owners to inspect and evaluate bridge conditions more effectively and efficiently with less …
Analysis Of Driving Behavior At Expressway Toll Plazas Using Driving Simulator, Moatz Saad
Analysis Of Driving Behavior At Expressway Toll Plazas Using Driving Simulator, Moatz Saad
Electronic Theses and Dissertations
The objective of this study is to analyze the driving behavior at toll plazas by examining multiple scenarios using a driving simulator to study the effect of different options including different path decisions, various signs, arrow markings, traffic conditions, and extending auxiliary lanes before and after the toll plaza on the driving behavior. Also, this study focuses on investigating the effect of drivers' characteristics on the dangerous driving behavior (e.g. speed variation, sudden lane change, drivers' confusion). Safety and efficiency are the fundamental goals that transportation engineering is always seeking for the design of highways. Transportation agencies have a crucial …
Experimental Study Of Sinkhole Failure Related To Groundwater Level Drops, Mohamed Alrowaimi
Experimental Study Of Sinkhole Failure Related To Groundwater Level Drops, Mohamed Alrowaimi
Electronic Theses and Dissertations
Sinkholes are natural geohazard phenomena that cause damage to property and may lead to loss of life. They can also cause added pollution to the aquifer by draining unfiltered water from streams, wetland, and lakes into the aquifer. Sinkholes occur in a very distinctive karst geology where carbonate, limestone, dolomite, or gypsum, are encountered as the bedrock that can naturally be dissolved by groundwater circulating through them. Sinkholes can occur gradually or suddenly with catastrophic impact depending on the geology and hydrology of the area. Predicting the formation and the collapse of a sinkhole based on the current ground investigation …
Impact Of Dynamic Message Signs On Driver Behavior Under Reduced Visibility Conditions, Ryan Selby
Impact Of Dynamic Message Signs On Driver Behavior Under Reduced Visibility Conditions, Ryan Selby
Electronic Theses and Dissertations
Fog along roadways is a dangerous hazard that leads to crashes resulting from limited visibility. Low visibility gives drivers less time to react to potential obstacles that can suddenly appear and require immediate action. To solve this issue, early warning systems involving Dynamic Message Signs or other types of devices are used to alert drivers of the impending visibility condition so that they are prepared. This research focuses on testing the effectiveness of one form of warning systems to investigate how it impacts driver behavior in foggy conditions. To accomplish this objective, a simulation study is developed to test variables …
Microscopic Safety Evaluation And Prediction For Special Expressway Facilities, Ling Wang
Microscopic Safety Evaluation And Prediction For Special Expressway Facilities, Ling Wang
Electronic Theses and Dissertations
Expressways are of great importance and serve as the backbone of a roadway system. One of the reasons why expressways increase travel speeds and provide high level of services is that limited access is provided to permit vehicles to enter or exit expressways. Entering and exiting of vehicles are accomplished through interchanges, which consist of several ramps, thus the spacing between ramps is important. A weaving segment might form when an on-ramp is closely followed by an off-ramp. The geometric design of ramps and the traffic behavior of weaving segments are different from other expressway segments. These differences result in …
Understanding Hydroclimatic Controls On Stream Network Dynamics Using Lidar Data, Seoyoung Kim
Understanding Hydroclimatic Controls On Stream Network Dynamics Using Lidar Data, Seoyoung Kim
Electronic Theses and Dissertations
This dissertation investigates the hydroclimatic controls on drainage network dynamics and characterizes the variation of drainage density in various climate regions. The methods were developed to extract the valley and wet channel networks based on Light Detection and Ranging (LiDAR) data including the elevation and intensity of laser returns. The study watersheds were selected based on the availability of streamflow observations and LiDAR data. Climate aridity index was used as a quantitative indicator for climate. The climate controls on drainage density were re-visited using watersheds with minimal anthropogenic interferences and compared with the U-shape relationship reported in the previous studies. …
The Effect Of Building Information Modeling On Design And Construction Industry, Yahya Alassaf
The Effect Of Building Information Modeling On Design And Construction Industry, Yahya Alassaf
Electronic Theses and Dissertations
Construction industry's evolution is, historically, in the lowest level, if compared to other industries, such as auto manufacturing. Construction is a multidisciplinary industry, considering that designers, contractors, and owners are all involved in the same project, each one seeking their own interests. The complex environment surrounding design and construction makes the decision-makers hesitate about adopting new methodology. Building Information Modeling (BIM) is a new method and technology, which can improve both the design and the construction processes. The adoption of BIM is increasing significantly over the last years, and its effects can be seen on real life projects. In order …
An Integrated Hydrodynamic-Marsh Model With Applications In Fluvial, Marine, And Mixed Estuarine Systems, Karim Alizad
An Integrated Hydrodynamic-Marsh Model With Applications In Fluvial, Marine, And Mixed Estuarine Systems, Karim Alizad
Electronic Theses and Dissertations
Coastal wetlands experience fluctuating productivity when subjected to various stressors. One of the most impactful stressors is sea level rise (SLR) associated with global warming. Research has shown that under SLR, salt marshes may not have time to establish an equilibrium with sea level and may migrate landward or become open water. Salt marsh systems play an important role in the coastal ecosystem by providing intertidal habitats and food for birds, fish, crabs, mussels, and other animals. They also protect shorelines by dissipating flow and damping wave energy through an increase in drag forces. Due to the serious consequences of …
Mechanistic Behavior Of Uhpc And Uhpc Composite Structural Components, Munaf Al-Ramahee
Mechanistic Behavior Of Uhpc And Uhpc Composite Structural Components, Munaf Al-Ramahee
Electronic Theses and Dissertations
The resistance of reinforced concrete is mobilized through the composite action of two materials with different mechanical behaviors and physical features. Enabling the composite action requires a transfer mechanism between the concrete and the reinforcement which is referred to as bond. The bond model can be defined as a traction-slip relation tangent to the interface. The bond strength between different types of concrete, internal reinforcement, and external reinforcement has been of interest to structural engineers for decades. Experimental tests have been carried out to validate the existing bond models and introduce new bond models for special cases of concrete or …
Impact Of The Longer Change And Clearance Intervals On Signalized Intersections And Corridors, Mohammed Alfawzan
Impact Of The Longer Change And Clearance Intervals On Signalized Intersections And Corridors, Mohammed Alfawzan
Electronic Theses and Dissertations
Evaluating the impact of longer change and clearance intervals on signalized intersections and corridors is the main goal of this study. In fact, the Florida department of Transportation (FDOT) has adopted a new signal retiming effort in a number of signalized intersections along several corridors. The Orange County started implementing the new signal timing from December, 2013 and completed it in June, 2015. The other objective of this new signal timing is to minimize the red light running rate. This study is dedicated to investigate the signal retiming effort adopted by the FDOT and how the new signal timing might …
Evaluation Of Real World Toll Plazas Using Driving Simulation, Kali Carroll
Evaluation Of Real World Toll Plazas Using Driving Simulation, Kali Carroll
Electronic Theses and Dissertations
Toll plazas are becoming an essential part of the highway system, especially within the state of Florida. Many crashes reported on highways occur at toll plazas. A primary reason for many vehicle collisions happening at these facilities is the fact that each toll plaza agency has different design, signage and marking criteria. This, in turn, causes driver confusion and possible last minute weaving maneuvers. Even though the varying design of toll plazas is a clear highway safety factor, research in the field is very limited but expanding. This study focuses on one toll plaza, in particular the Dean Mainline Toll …
Getting To Net Zero Energy Buildings: A Holistic Techno-Ecological Modeling Approach, Mehdi Alirezaei
Getting To Net Zero Energy Buildings: A Holistic Techno-Ecological Modeling Approach, Mehdi Alirezaei
Electronic Theses and Dissertations
Buildings in the United States are responsible for more than 40% of the primary energy and 70% of electricity usage and greatly in CO2 emission by about 39%, more than any other sector including transportation and industry sectors. This energy consumption is expected to grow mainly due to increasing trends in new buildings construction. Rising energy prices alongside with energy independencies, limited resources, and climate change have made the current situation even worse. An Energy Efficient (EE) building is able to reduce the heating and cooling load significantly compared with a code compliant building. Furthermore, integrating renewable energy sources in …
Computer Vision Based Structural Identification Framework For Bridge Health Mornitoring, Tung Khuc
Computer Vision Based Structural Identification Framework For Bridge Health Mornitoring, Tung Khuc
Electronic Theses and Dissertations
The objective of this dissertation is to develop a comprehensive Structural Identification (St-Id) framework with damage for bridge type structures by using cameras and computer vision technologies. The traditional St-Id frameworks rely on using conventional sensors. In this study, the collected input and output data employed in the St-Id system are acquired by series of vision-based measurements. The following novelties are proposed, developed and demonstrated in this project: a) vehicle load (input) modeling using computer vision, b) bridge response (output) using full non-contact approach using video/image processing, c) image-based structural identification using input-output measurements and new damage indicators. The input …
Estimating A Freight Mode Choice Model: A Case Study Of Commodity Flow Survey 2012, Nowreen Keya
Estimating A Freight Mode Choice Model: A Case Study Of Commodity Flow Survey 2012, Nowreen Keya
Electronic Theses and Dissertations
This research effort develops a national freight mode choice model employing data from the 2012 Commodity Flow Survey (CFS). While several research efforts have developed mode choice model with multiple modes in the passenger travel context, the literature is sparse in the freight context. The primary reasons being unavailability and/or the high cost associated with the acquisition of mode choice and level of service (LOS) measures – such as travel time and travel cost. The first contribution of the research effort is to develop travel time and cost measures for various modes reported in the CFS. The study considers five …
Joint Modeling Of Traffic Related Crashes: A Copula Based Approch, Tammam Nashad
Joint Modeling Of Traffic Related Crashes: A Copula Based Approch, Tammam Nashad
Electronic Theses and Dissertations
The study contributes to safety literature on transportation safety by employing copula based models for count frequency analysis at a macro-level. Most studies in the transportation safety area identify a single count variable (such as vehicular, pedestrian or bicycle crash counts) for a spatial unit and study the impact of exogenous variables. While the traditional count models perform adequately in the presence of a single count variable, it is necessary to modify these approaches to examine multiple dependent variables for each study unit. To that extent, the current research effort contributes to literature by developing two multivariate models based on …
Sinkhole Monitoring Using Groundwater Table Data, Ton Tu
Sinkhole Monitoring Using Groundwater Table Data, Ton Tu
Electronic Theses and Dissertations
Florida might be one of the most sinkhole-active areas on the earth. Due to its unpredictability and significance of occurrence, the development of sinkhole monitoring techniques is imperative to minimize sinkhole-induced hazards. Several methods have been used to evaluate sinkhole risks, including destructive methods, such as Standard Penetrating Tests (SPT) and Cone Penetrating Tests (CPT), geophysical method, and sensor-based groundwater monitoring method. However, few studies are available for comprehensive understanding of spatiotemporal sinkhole mechanism by combining different exploration methods under realistic experimental conditions. The objective of this study is to understand spatiotemporal sinkhole mechanism, using SPT, CPT, ground penetrating radar …
Dynamic Modeling Approach To Quantify Change Orders Impact On Labor Productivity, Zain Al-Kofahi
Dynamic Modeling Approach To Quantify Change Orders Impact On Labor Productivity, Zain Al-Kofahi
Electronic Theses and Dissertations
In construction projects, change orders are commonly faced. These change orders, which are issued by the owner, may cause interruption to the contractor's work, resulting in damages such as loss of labor productivity, delay damages, and cost overruns which may lead to claims. The relationship between change orders and loss of labor productivity is not well understood because of the difficulty in linking the cause of the productivity loss to the change order. So, to receive compensation, the contractor needs to prove with a credible calculation that the productivity loss was a result of the change order issued by the …
Evaluating Wrong-Way Driving For Florida Interstates And Toll Road Facilities: A Risk-Based Investigation, And Countermeasure Development, John Rogers
Electronic Theses and Dissertations
The focus of this dissertation was to examine wrong-way driving (WWD) events on Florida toll roads and Interstates. The universe of WWD data contains many sources of WWD events or incidents. Most of the previous research focused only on WWD crashes without considering other data such as WWD citations and 911 calls related to WWD incidents. While WWD citations and 911 calls data is abundant, this data has been largely overlooked in other studies. This dissertation provides a novel and holistic approach for evaluating WWD risk, which considers other risk factors such as WWD citations and 911 calls in addition …
Structural Health Monitoring Of Composite Overwrapped Pressure Vessels, Luca Letizia
Structural Health Monitoring Of Composite Overwrapped Pressure Vessels, Luca Letizia
Honors Undergraduate Theses
This work is focusing to study the structural behavior of Composite Overwrapped Pressure Vessels (COPVs). These COPVs are found in many engineering applications. In the aerospace field, they are installed onto spaceships and aid the reorientation of the spacecraft in very far and airless, therefore frictionless, orbits to save energy and fuel. The intent of this research is to analyze the difference in performance of both perfectly intact and purposely damaged tanks. Understanding both the source and location of a structural fault will help NASA engineers predict the performance of COPVs subject to similar conditions, which could prevent failures of …