Civil Engineering Commons^™

A System Architecture For Water Distribution Networks, Noha Abdel-Mottaleb

USF Tampa Graduate Theses and Dissertations

This dissertation examines structure-function relationships of water distribution networks (WDNs), with focus on improving the decision-making process for water utilities. WDNs are lifeline infrastructure systems, necessary for the functioning of cities. Yet water utilities around the world struggle with emerging challenges that include but are not limited to aging infrastructure components, limited budgets, increased interdependencies between infrastructure systems, increased rates of urbanization, and increasing extreme weather conditions. This is why enhancing the performance of WDNs is a priority for water utilities around the world. This research begins to delineate a system architecture for WDNs and evaluates the use of various …

An Assessment And Exploration Of Recent Methodological Advances In Safety Data Analysis, Suryaprasanna Kumar Balusu

USF Tampa Graduate Theses and Dissertations

The injury severity and frequency of traffic crashes can be further reduced by implementing appropriate traffic safety measures. Several advanced methodologies have been developed in the recent decades to more accurately identify the factors affecting road safety. Such methodologies have helped policy makers formulate appropriate safety measures directed toward increasing seatbelt and helmet use, reducing speed limits in school zones, implementing adolescent driver programs, and so on. However, each methodological approach has its own strengths and weakness and could lead to different inferences. This dissertation assesses and explores a number of recently developed methodologies and their application to traffic safety …

Minimum Cut-Sets For The Identification Of Critical Water Distribution Network Segments, Xiliang Mao

USF Tampa Graduate Theses and Dissertations

To ensure adequate performance of water distribution networks, utilities must identify critical segments within the network that will adversely affect users when failures occur. Currently, time consuming hydraulic simulations are used for such criticality analyses. A method can be of great benefit for utilities if it can easily evaluate the criticality of water distribution network segments. This research applies topology-based methods for the preliminary screening of critical segments. This study evaluated the connectivity between sources and each demand segment in water distribution networks using minimum cut-sets. Through topological analysis, the minimum cut -set between the source node and each demand …

Corrosion Propagation Of Stainless Steel Reinforced Concrete, Nelly Sofía Orozco Martínez

USF Tampa Graduate Theses and Dissertations

Structural durability is a growing concern in global infrastructure. The infrastructure report card released by the American Society of Civil Engineers (ASCE) indicates that approximately 9.1% of the total bridges in the United States were structurally deficient in 2016. In addition, it suggests that about 40% of the total bridges in the country are now 50 years or older. This issue becomes even more critical in structures exposed to aggressive environments such as marine structures. Thus, federal and regional efforts are now being directed towards infrastructural durability improvement to improve the long-term cost-efficiency of civil infrastructure.

Corrosion prevention strategies may …

Influence Of Coating Defects Within The Lock Seams On The Corrosion Performance Of Aluminized Steel Drainage Pipes, Mohammed Al Yaarubi

USF Tampa Graduate Theses and Dissertations

The electrochemical behavior of aluminized steel is investigated to determine the corrosion performance of coating deficiencies generated within the lock seams during the fabrication of aluminized steel corrugated pipe. Electrochemical techniques and visual and profilometric analysis are used to assess the ability of the aluminum and zinc coating to provide sufficient galvanic protection to the underlying steel in the presence of a crevice. Also, Crevice coupons and lock-seam samples were used in this investigation in different environmental conditions simulating natural water conditions to relate the corrosion rate with the level of protection that the coating will provide. In addition, a …

Corrosion Durability Service Life Of Calcium Silicate-Based Reinforced Concrete, Carolina Páez Jiménez

USF Tampa Graduate Theses and Dissertations

Corrosion of reinforcing steel is a major area of study for assessing durability of reinforced concrete infrastructure. Conventional concrete infrastructure designs use ordinary Portland cement (OPC) as the primary cementitious material. However, the world's current challenge to achieve sustainable development requires the cement industry to reduce its environmental impact, as it is responsible for 8% of the anthropogenic CO2 emissions. Hence, a new type of cement has been developed. This novel calcium silicate cement (CSC) reduces the carbon dioxide emissions during its manufacturing process as compared to OPC, providing an environmentally-sound alternative for reinforced concrete fabrication.

Corrosion of steel reinforcement …

Corrosion Rate Prediction In Frp-Concrete Repair, Mohammad A. Khawaja

USF Tampa Graduate Theses and Dissertations

Research has proven that wrapping structural elements with fiber-reinforced polymers (FRPs) slows down chloride-induced corrosion rate but does not stop it. Although FRP has been used for corrosion repair for over 40 years, predictive corrosion rate models for FRP-concrete systems are limited in literature. This dissertation presents an oxygen diffusion-based predictive framework to estimate corrosion rate in FRP-concrete systems.

The dissertation has three main components. First, a core framework that is referred to as Khawaja-Sen-Bhethanabotla (KSB) model. In the KSB model, statistical methods were used to extend experimental data on oxygen permeation coefficients. These data were for one and two …

Longitudinal Trajectory Tracking Analysis For Autonomous Electric Vehicles Based On Pid Control, Hossein Amiri

USF Tampa Graduate Theses and Dissertations

The implementation of autonomous vehicles has huge potential for revolutionizing transportation as we currently know it. All use cases of autonomous vehicles require the vehicle to travel on a pre-specified path. Accurate tracking of this defined trajectory is a crucial aspect of the implementation of autonomous vehicles; a controller system is required to translate this pre- defined trajectory in the form of the throttle, brake, and steering inputs. This project covers the application of a Proportional-Integral-Derivative (PID) controller to achieve longitudinal trajectory tracking of autonomous electric vehicles with stability and accuracy in the CARLA autonomous driving simulation platform. The implemented …

Prediction Of The Effects Of Turbulence On Vehicle Hydroplaning Using A Numerical Model, Thathsarani Dilini Herath Herath Mudiyanselage

USF Tampa Graduate Theses and Dissertations

Pneumatic hydroplaning has been identified as one of the major causes of wet weathertraffic accidents. Therefore, knowledge of potential hydroplaning speeds is crucial in designing roadways to reduce crash risks. It has been shown that the tire inflation pressure is the predominant factor affecting the hydroplaning speed while factors such as the water film thickness also contribute heavily to this phenomenon. Extensive research has been directed at the development of accurate models to predict the effects of vehicle characteristics, pavement conditions and water film thickness on hydroplaning. Current literature does not indicate any studies directed at understanding the effects of …

Feasibility Of Epoxy Bond Enhancement On High-Strength Concrete, Amanda A. Lewis

USF Tampa Graduate Theses and Dissertations

While fiber-reinforced polymer materials have many applications in various industries,when used structurally, many cases, such as flexural and shear strengthening, are considered bond critical. Interfacial bond quality between a fiber-reinforced polymer system and the substrate is dependent on two mechanisms: chemical bonding and mechanical interlock, with mechanical interlock having the greater effect on bond quality. Mechanical interlock describes the type of bond that occurs as a result of surface roughness and substrate porosity and can be significantly affected by surface preparation methods and surface moisture. This study aims to explore the possibility of enhancing bond quality between carbon-fiberreinforced polymers and …

The Effect Of Cement And Blast Furnace Slag Characteristics On Expansion Of Heat-Cured Mortar Specimens, Jair G. Burgos

USF Tampa Graduate Theses and Dissertations

Delayed ettringite formation (DEF) is a durability issue that typically occurs in concrete exposed to high temperatures at an early age such as precast elements and massive concrete structural elements. There are many advantages to precast concrete such as its quality control, better safety control, and reusable forms, which make them cheaper than casting on site [1]. Heat curing of precast concrete is conducted to obtain high early-strength. However, in doing so, durability issues can arise in the form of internal sulfate attack also known as DEF, if the internal temperature of concrete exceeds 70°C. Past this threshold, ettringite decomposes …