Civil Engineering Commons^™

Hydraulic Performance And Vulnerability On Sanitary Sewer Overflow In Southern Pinellas County, Fl, Uchechi O. Akabogu

USF Tampa Graduate Theses and Dissertations

Rain-induced sanitary sewer overflow due to high infiltration is a significant challenge for many utilities, including Pinellas County utilities. The main aim of this study is to develop a hydraulic model to analyze the performance of the existing sanitary sewer system, especially during intense rainfall events.

To calculate the flow inputs for the model, a times series analysis was performed to separate the inflow and infiltration from the actual sewer flow. Using the Stevens-Schutzbach method, daily Base Infiltration (BI) was calculated and was subtracted from the total observed flow to give the Dry Weather Flow (DWF). Adjusting the DWF by …

Efficient Adjacency Queries And Dynamic Refinement For Meshfree Methods With Applications To Explicit Fracture Modeling, James Olliff

USF Tampa Graduate Theses and Dissertations

Meshfree methods provide a more practical approach to solving problems involving large deformation and modeling fracture compared to the Finite Element Method (FEM). However meshfree methods are more computationally intensive compared to FEM, which can limit their practicality in engineering. Meshfree methods also lack a clear boundary definition, restricting available visualization techniques. Determining particle locations and attributes such that a consistent approximation is ensured can be challenging in meshfree methods, especially when employing h-refinement. The primary objective of this work is to address the limitations associated with computational efficiency, meshfree domain discretization, and h-refinement, including both placement of particles as …

Underground Stormwater Treatment Performance In Urban Coastal Catchments: Case Study Of Baffle Boxes In The City Of Tampa, Awet Eyob Tsegay

USF Tampa Graduate Theses and Dissertations

In coastal urban regions, underground stormwater treatment units are suitable infrastructure options because they take less space where premium land is expensive. Even then, they should be accessible and ideally small enough to fit into existing stormwater networks. Since 2003, the City of Tampa and Florida’s Department of Transportation (FDOT) have installed 47 baffle boxes into the city’s stormwater pipe networks. Baffle boxes are underground stormwater treatment structures designed to capture sediments and floating debris. Since their deployment, many challenges regarding their practical sediment capturing performance was raised by the city.

The objective of this research was to evaluate the …

Investigations On Frp-Concrete Bond, Mostfa Al Azzawi

USF Tampa Graduate Theses and Dissertations

This dissertation presents findings from three separate investigations, a laboratory study and two field studies that evaluated the durability of the Fiber Reinforced Polymer (FRP)-concrete bond. The laboratory study explored the role of porosity on CFRP-concrete bond following immersion in warm water. Two disparate field studies measured residual bond after 20 years outdoor exposure of FRP repairs of full-size masonry walls and after 12 years for partially submerged piles supporting the Friendship Trail Bridge, Tampa Bay.

The ACI 440 code requires the same surface preparation for all externally bonded FRP concrete repairs. This disregards the role of porosity that is …

Assessment Of Drinking Water Quality Management And A Treatment Feasibility Study For Brick By Brick Water Storage Tanks In Rakai Uganda, James V. Murduca

USF Tampa Graduate Theses and Dissertations

Reliable access to safe drinking water is one necessity for humans to live without concern for major health risks. The overall goal of this research is to improve the public health, through improved drinking water, for communities in the Rakai District in Uganda, directly, and other communities in the world, indirectly, via dissemination of knowledge. This study specifically assessed the knowledge of drinking water quality in regards to public health, their sanitation measures, and water treatment methods for users of Brick by Brick rainwater harvesting tanks in the Rakai District (N = 28) by using a knowledge, attitudes, and practice …

Modeling Corrosion Damage And Repair To A 3, Joseph R. Scott

USF Tampa Graduate Theses and Dissertations

The main purpose of this study was to investigate and implement a repair design for corrosion damaged bridge bents in order to resist lateral loading, such as wind loads or ship impact. Using the results from a one-third scale bridge bent constructed and tested for a previous study, non-linear modeling was used to simulate the same corrosion damage and load response. The principle variable considered was damage, represented as a percent of effective area loss of prestressing steel within a designated damage zone along the length of piles. Other influencing variables included: prestress transfer length, localized loss in prestress due …

Assessing The Impacts Of Climate Change On Streamflow And Reservoir Operation In Central Florida, Toni Panaou

USF Tampa Graduate Theses and Dissertations

Climate change is a global concern as it may affect many aspects of life, including water supply. A tool used to model climate change’s impacts is called a General Circulation Model (GCM). GCMs project future scenarios including temperature and precipitation, but these are designed at a coarse resolution and require downscaling for employment for regional hydrologic modeling. There is a vast amount of research on downscaling and bias-correcting GCMs data, but it is unknown whether these techniques alter precipitation signals embedded in these models or reproduce climate states that are viable for water resource planning and management. Using the Tampa, …

Construction Effects On The Side Shear Of Drilled Shafts, Lucas Caliari De Lima

USF Tampa Graduate Theses and Dissertations

Design methods for side shear of drilled shafts, including the resistance factors that should be applied, do not account for any specific construction procedure. Instead, design often relies on analysis of case studies which include all construction methods used in each geomaterial type (e.g. clays, sands and rocks), or on parametric analysis. Nonetheless, literature suggests that different construction procedures result in varying side shear.

This research investigated 2 types of construction: (1) slurry stabilization in sandy soils using bentonite and polymer products that are commonly used on the field, with exposure times from near 0h to 96h, and (2) temporary …

Dns And Les Of Scalar Transfer Across An Air-Water Interface During Inception And Growth Of Langmuir Circulation, Amine Hafsi

USF Tampa Graduate Theses and Dissertations

Direct numerical simulations (DNS) of an initially quiescent coupled air-water interface driven by an air flow with free stream speed of 5 m/s have been conducted. The DNS solves a scalar advection-diffusion equation for dissolved gas (or scalar) concentration in order to determine the impact of the water-side turbulence on scalar (mass) transfer from the air side to the water side and subsequent vertical transport in the water column. Two simulations are compared: one with a freely deforming interface and a second one with a flat interface. In the first simulation, the deforming interface evolves in the form of gravity-capillary …

Analysis Of Distresses In Asphalt Pavement Transitions On Bridge Approaches And Departures, Manvitha Rajalingola

USF Tampa Graduate Theses and Dissertations

Some highway agencies in the United States are experiencing frequent distresses in asphalt pavements on bridge approaches/departures. Commonly observed distresses include alligator cracking and rutting, which reduce roadway smoothness and safety. To lessen the distresses in pavements it is needed to investigate the extent and root causes of the problem. Based on Florida highway conditions, this research study mainly focused on1. Literature review and identification of the extent of the problem; 2. Collection of relevant pavement condition data and descriptive analysis; 3. Development of statistical models to determine factors influencing the distresses in asphalt pavements on bridge approaches/departures. To the …

How Transportation Network Companies Could Replace Public Transportation In The United States, Matthew L. Kessler

USF Tampa Graduate Theses and Dissertations

The quantity of cell phone applications or mobile apps have seen an upsurge at an exponential rate in under a decade. Many have been created for a variety of industries, including transportation. The advent and subsequent commercialized implementation of near-instant transport by a middleman-type of app is now known as a Transportation Network Company or TNC. Examples of the more renowned TNCs are Uber, Lyft and Sidecar.

In recent years, TNCs have cultivated a tremendous following, to the degree of taxicab desertion. Moreover, the massive success of TNCs led to expansion of its capacities into public transportation.

The TNC’s expeditious …

The Effect Of Chemical Composition Of Blast-Furnace Slag On Compressive Strength And Durability Properties Of Mortar Specimens, William J. Johnson

USF Tampa Graduate Theses and Dissertations

In an effort to make structures more sustainable and durable, supplementary cementitious materials are often used to replace cement. Ground granulated blast furnace slag, for instance, is an industrial by-product of iron refinement and is frequently used in concrete mixture design to not only reduce cost, but also increase later-age strength as well as durability. However, published literature indicates that slags with a high alumina content may have a detrimental effect when concrete is exposed to a sulfate environment. ASTM standard C989 does not suggest any information or guidelines regarding using slags with an alumina content between 11-18%. Therefore, the …

Sustainability Of Community-Managed Rural Water Supply Systems In Amazonas, Peru: Assessing Monitoring Tools And External Support Provision, Jacob E. Mangum

USF Tampa Graduate Theses and Dissertations

Globally, there is still a large number of people without access to safe drinking water; a known health risk. In rural areas of countries like Peru, when potable water systems are built the responsibility for maintaining these systems is given to volunteer water committees. Despite its prevalence as a management model, there is a consensus that community management alone cannot ensure sustainable water service. Therefore, the overall goal of this research is to assess the sustainability of community-managed water systems in rural areas of the department of Amazonas, Peru. Specifically, this research examines two mechanisms that have been shown to …

Autonomous Vehicles: An Empirical Assessment Of Consumers’ Perceptions, Intended Adoption, And Impacts On Household Vehicle Ownership, Nikhil Menon

USF Tampa Graduate Theses and Dissertations

Emerging automotive and transportation technologies have provided revolutionary possibilities in the way we might travel in the future. Major car manufacturers and technology giants have demonstrated significant progress in advancing and testing autonomous vehicles in real-life traffic conditions. Governmental agencies are grappling with how to plan transportation systems for a world with autonomous vehicles. Past research has shown that not all technologies are immediately welcomed by the public. Autonomous Vehicles would have to likely go through a similar phase, and would need to overcome not just technological challenges but also social barriers for successful penetration into the marketplace. Most previous …

Quantifying And Modeling Surface Inflow And Groundwater Infiltration Into Sanitary Sewers In Southern Pinellas County, Fl, Megan E. Long

USF Tampa Graduate Theses and Dissertations

Following large rain events, excess flow in sanitary sewers from inflow and infiltration (I/I) cause sanitary sewer overflows (SSO), resulting in significant problems for Pinellas County and the Tampa Bay area. Stormwater enters the sanitary sewers as inflow from improper or illegal surface connections, and groundwater enters the system as infiltration through cracks in subsurface infrastructure. This pilot study was designed to develop methods to separate and quantify the components of I/I and to build a predictive model using flowmeter and rainfall data.

To identify surface inflow, daily wastewater production and groundwater infiltration patterns were filtered from the flow data, …

Recommendation Of A New Transit Performance Measure In The National Transit Database, Fatemeh Baratian-Ghorghi, Hossein Ahmadianyazdi

Journal of Public Transportation

The frequency of incidents negatively changes public perception with regard to the public safety in transit systems. The level of safety expressed as performance measures, ensures contractors and users that a quality safety level is maintained. Both the private and public sectors in the U.S. annually report accurate data to the National Transit Database (NTD) to be used in assessing the progress of the nation's public transportation systems. Although they must provide both the annual report and monthly reports including Safety and Security data, measures are only grouped into the indicators of efficiency and effectiveness of a system and there …

Evaluating The Effect Of Temporary Casing On Drilled Shaft Rock Socket Capacity, Daniel J. Hagerman

USF Tampa Graduate Theses and Dissertations

The purpose of this study was to determine the effect on side shear resistance in limestone when temporary casing is used. Due to testing in actual limestone being an unrealistic goal, simulated limestone mixes were prepared and cast into 6 – 42 in. diameter beds. Limestone throughout Florida can be quite varied (e.g. 50-5000 psi) but where stronger limestone is not likely to be penetrated by casing installation. Therefore, target unconfined compressive strengths of the study specimens ranged between 60 psi to 850 psi.

A simulated limestone material was developed based on over 200 cylinders cast for unconfined compression testing …

Mechanism Of Cathodic Prevention Of Carbon Steel In Concrete, Krittin Rattakham

USF Tampa Graduate Theses and Dissertations

In this work, I aim to clarify the mechanism that allows steel to attain higher chloride threshold as it is cathodically polarized. Specifically, I seek to provide empirical information on whether an intrinsic (predominantly interfacial effects of polarization) or an extrinsic (predominantly concentration changes due to polarization) mechanism may be dominant in the beneficial effect of polarization. I carried out this experiment with 12 identical concrete specimens, each with a cast-in steel plate, constantly exposed them to high-chloride environment. The specimens were divided into 4 triplicates and polarized at 4 different level from OCP, -200, -300 to -400 mV_{SCE …}

Electrochemical Methods To Characterize Drilled Shaft Deficiencies, Sarah Jo Mobley

USF Tampa Graduate Theses and Dissertations

In recent years drilled shafts have become the preferred foundation method for marine bridges. Typically, the drilled shaft is selected over traditional driven piles due to soil strata encountered, construction economy, increased lateral stiffness requirements, and/or vibration control considerations. The most critical component in drilled shaft construction is borehole stabilization. Wall sloughing or groundwater inclusion can have devastating effects on the strength of the finished shaft however recent research has shown that the materials, more specifically the slurry, used to accomplish stabilization may be having a negative impact on the durability of the finished product. This thesis investigates the durability …

Advancements In Thermal Integrity Profiling Data Analysis, Kevin Russell Johnson

USF Tampa Graduate Theses and Dissertations

Thermal Integrity Profiling (TIP) is a relatively new non-destructive test method for evaluating the post-construction quality of drilled shafts. Therein anomalies in a shaft are indicated by variations in its thermal profile when measured during the curing stages of the concrete. A considerable benefit with this method is in the ability to detect anomalies both inside and outside the reinforcement cage, as well as provide a measure of lateral cage alignment. Similarly remarkable, early developments showed that the shape of a temperature profile (with depth) matched closely with the shape of the shaft, thus allowing for a straightforward interpretation of …

Effective Post-Tensioned Splicing System For Prestressed Concrete Piles, Zhongxin Wu

USF Tampa Graduate Theses and Dissertations

Precast prestressed concrete piles are widely used in deep foundation construction. Due to unexpected site soil conditions and difficulties associated with transportation and handling long precast piles, splicing is sometimes necessary at the construction site.

Available splicing methods utilize steel type connections that are more suitable for reinforced concrete construction and result in limited tensile capacity at the splice. This dissertation describes studies associated with the development of a new post-tensioned splicing system using staggered, embedded anchorages. The new system has the potential to provide the same tensile capacity as a one piece prestressed pile.

To develop the post-tensioned splicing …

Cracking Potential And Temperature Sensitivity Of Metakaolin Concrete, Andrew Robert Williams

USF Tampa Graduate Theses and Dissertations

Metakaolin is a pozzolanic material with the potential to reduce permeability and chloride ingress; however, quantification of the effects of metakaolin use on the cracking sensitivity of concrete mixtures is needed to ensure that these improvements in performance are not compromised. This study was conducted to investigate the early age cracking potential due to restraint stresses from incorporating metakaolin in concrete. Calorimetry testing showed that metakaolin was more sensitive to temperature than mixtures with only Portland cement. Results showed more shrinkage, less stress relaxation, and higher restraint stress from the inclusion of metakaolin, potentially increasing cracking sensitivity of mixtures.

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Time Dependent Effect Of Drilling Slurries On Side Shear Resistance Of Drilled Shafts, Warren Allen

USF Tampa Graduate Theses and Dissertations

Drilled shafts are cylindrical deep foundations constructed by casting fluid concrete into an excavated hole. These elements rely largely on side shear resistance generated by their substantial diameters and lengths to effectively transfer loads. Therefore, an exceptional concrete to soil interface is essential for proper performance of these structures. The FDOT preferred stabilization fluid, bentonite slurry, has been proven to degrade this interface with increased exposure time due to filter cake formation. For this reason, slurry exposure time has been limited to 36 hours by FDOT. Alternately, polymer slurries do not form a filter cake but rather stabilize excavations through …

Investigation Of Future Flow Reducer Sizes In Houses Added To An Existing Gravity Flow Water System To Ensure Its Sustainability, Michelle Roy

USF Tampa Graduate Theses and Dissertations

Goal 6 of the United Nations Development Program’s new Sustainable Development Goals aims to ensure availability of clean water and sustainable management practices to all by the year 2030. Peace Corps Panama partners with communities in order to help provide sustainable water solutions to communities in need. Water, Sanitation, and Hygiene (WASH) Volunteers spend at least two years living in a community to identify and implement solutions to water problems and train local water committees on how to maintain their improved systems. A common solution for unequal distribution of flow in the distribution network of a gravity flow water system …

Automated Device To Measure Slurry Properties In Drilled Shafts, Miles Patrick Mullins

USF Tampa Graduate Theses and Dissertations

Slurry is the fluid within a drilled excavation that is introduced when an excavation is deeper than the water table or where additional stability is needed for loose sandy dry soils. Although construction practices vary greatly throughout the country and the world, slurry levels should be maintained above the existing ground water level by a suitable margin. The most widely used slurry type is mineral slurry formed by mixing dry clay powder with water; either bentonite or attapulgite powder may be used (attapulgite being used in saline water conditions). Regardless of whether the slurry material is mineral, polymer or natural, …

Computational Code For Optimization Of Thermal Treatment Of Fine Grained Soils As A Method Of Expediting Their Load Induced Consolidation, Radhavi Abeysiridara Samarakoon

USF Tampa Graduate Theses and Dissertations

Construction in soft soils has been a challenging task for engineers due to the excessive time taken for dissipation of construction induced pore water pressure and the ensuing postconstruction settlement. Use of vertical drains has proven to be an effective and economical method for soft ground improvement and hence extensive research has been carried out to further improve its efficiency. Effect of temperature on radial consolidation is one aspect of such research among many others that have been pursued.

Elevated temperature certainly has a pronounced effect on the hydraulic conductivity due to the reduction it causes in the viscosity of …

Interaction Of Cementitious Systems With Chemical Admixtures, Natallia Shanahan

USF Tampa Graduate Theses and Dissertations

The use of supplementary cementitious materials (SCMs) in commercial construction have been increasing over the last several decades as climate change and sustainability has been gaining global attention. Incorporation of SCMs into concrete mixtures provides several environmental benefits. Since most SCMs are waste by-products of other industries, their use in concrete reduces waste disposal. Additionally, cements substitution with SCMs reduces the carbon footprint of the construction industry. Cement production generates large amounts of CO₂ emissions; the use of SCMs reduces the amount of cement in a concrete mixture thereby reducing emissions from its production.

In addition to SCMs, modern …

Sustainability At U.S. Urban Water Utilities: A Framework To Assess Key Attributes, Matthew Paul Ries

USF Tampa Graduate Theses and Dissertations

Urban water utilities in the United States face challenges due to a combination of external drivers. These include urbanization and population growth, which are stressing a system of aging infrastructure. Compliance with increasing regulations is also a challenge in a fiscally-constrained economic environment. A changing climate threatens infrastructure and past assumptions for water supply and quality. Urban utilities provide clean water and sanitation services to over 80% of the country’s population and its industrial centers. Therefore, the sustainability of these water utilities are crucial to the country’s and the public’s well-being.

New operating models are emerging for a “utility of …

In-Situ Testing Of Uretek's Injectable BarrierSm As A Mechanism For Groundwater Control, Jeremy Hess

USF Tampa Graduate Theses and Dissertations

Construction projects involving the installation or repair of subsurface structures or utilities often require dewatering to induce a temporary lowering of the local groundwater elevation to facilitate construction. In the event that a known contaminant plume is present in an adjacent area, this dewatering may inadvertently draw the contaminant into the previously uncontaminated work area. Uretek Holdings, Inc. has developed its Injectable Barrier^SM to be installed prior to dewatering exercises to provide a groundwater cut-off by reducing the potential movement of groundwater due to the hydraulic gradient induced by dewatering. A benefit of Injectable Barrier^SM as compared to …

Cement Heat Of Hydration And Thermal Control, Ahmadreza Sedaghat

USF Tampa Graduate Theses and Dissertations

Heat of hydration is a property of Portland cement and a direct result of the chemical reaction between cement and water. The amount of heat released is dependent upon the cement mineralogical composition, curing temperature, water to cement ratio, and cement fineness. High temperature resulting from heat of hydration (thereon referred to as HOH) of cement can affect the hydration process, and consequently the kinetics of development of the mechanical properties of concrete. One of the main reasons triggering the interest in HOH of cement is its implication in thermal cracking of concrete. The high temperature gradient between the inner …