Engineering Commons^™

Global And Local Performance Of Prestressed Girder Bridges With Positive Moment Continuity Detail, Tanvir Hossain

LSU Doctoral Dissertations

Global as well as local behavior of prestressed girder bridges made continuous by adding continuity diaphragms with a recently proposed positive moment continuity detail were investigated in this study. The focus of the investigation is on the positive moment caused by temperature gradients, time dependent effects such as creep and shrinkage, and some live load positions, and on the force transfer mechanisms through the diaphragm. The study utilized different approaches including analytical models for temperature evaluations and finite element models for structural assessments. Field data from a bridge using the new detail were used to validate the developed models. The …

On The Development Of The Extradosed Bridge Concept, Steven Lynn Stroh

USF Tampa Graduate Theses and Dissertations

The Extradosed Prestressed Bridge represents a relatively new bridge type. The first of this type bridge was constructed in Japan in 1994, and Japan has since built at least 29 examples of this bridge type. Throughout the rest of the world, another 34 of this bridge type have been built, with most countries having only one, or at most a few, examples. A broader application of this bridge type has been hampered by lack of design information and in particular lack design criteria for the stay cables. The purpose of this dissertation is to progress the understanding and application of …

Analysis And Remediation Of Chlorinated Hydrocarbons In Environmental Media, Jonathan Ticknor

USF Tampa Graduate Theses and Dissertations

The two objectives of this work were to develop a simplified method for the analysis of chlorinated organics in water samples and to improve an existing soil remediation technology. The contaminants considered for these studies were chlorinated hydrocarbons because of their relative frequency of appearance at contaminated sites. The first half of this study involved the analysis of chlorinated ethenes by gas chromatography with flame ionization detection (GC-FID). I tested the hypothesis that the FID response factor is the same for all chlorinated ethene compounds. The rationale for this investigation is that if the hypothesis is correct, a single calibration …

Corrosion Evaluation And Durability Estimation Of Aluminized Steel Drainage Pipes, Mersedeh Akhoondan

USF Tampa Graduate Theses and Dissertations

Aluminized steel pipes are expected to have a long service life, e.g. 75 years. Spiral ribbed aluminized pipes (SRAP) have been widely specified and used by the Florida Department of Transportation (FDOT) for drainage of runoff water. Confidence in the long term durability of SRAP has been challenged by recent unexpected early corrosion failures in various Florida locations. SRAP premature corrosion incidents have occurred in two modalities. Mode A has taken place in near-neutral soil environments and has often been associated with either gross manufacturing defects (i.e. helical cuts) or corrosion concentration at or near the ribs. Mode B took …

Optimization Of An Advanced Water Treatment Plant: Bromate Control And Biofiltration Improvement, Dustin William Bales

USF Tampa Graduate Theses and Dissertations

The David L. Tippin Water Treatment Facility (DLTWTF) serving the city of Tampa, Florida is an advanced drinking water treatment facility consisting of coagulation/flocculation, ozonation, granular activated carbon biofiltration, and disinfection by chloramine. New regulations and the recent economic crisis pushed the facility to investigate methods to decrease costs and meet regulatory requirements easier.

The two major issues identified as priorities for investigation were the optimization of the biofiltration system and the use of a novel process to reduce the formation of bromate during ozonation.

Optimization of the biofiltration system is needed to remove more of the assorted particles that …

Aggregation Of Sediment And Bacteria With Mucilage From The Opuntia Ficus-Indica Cactus, Audrey Lynn Buttice

USF Tampa Graduate Theses and Dissertations

Flocculants are commonly used in industrial settings where solid-liquid separations are desired including industrial and municipal wastewater management and potable water production facilities. Conventional flocculants include inorganic metal salts and synthetic organic polymers. The cost, availability, and harmful effects of the non-biodegradable nature of these flocculants have led to the widespread study of natural flocculants. Current natural flocculants being studied include polysaccharides cultivated from microbial extracellular matrix products and plant based materials. In this study, the mucilage of Opuntia ficus-indica cactus was evaluated as a natural flocculant for sediments and bacteria. The O. ficus-indica cactus is also known as the …

Numerical Simulation Of Sliding Friction And Wet Traction Force On A Smooth Tire Sliding On A Random Rough Pavement, Janaka Vishwanath Kosgolla

USF Tampa Graduate Theses and Dissertations

Availability of analytical and numerical tools that can provide reliable and accurate estimates of wet frictional resistance in different pavements would preclude the need for time consuming field tests. Therefore, many research efforts have been made to develop such tire-pavement friction predictive tools that are invaluable for friction management programs. However, due to the complexity of the problem, most existing tools have been developed based on several simplifying assumptions and without field verification of their predictions. The current study is focused on the evaluation of two specific prediction methods that can be used to predict friction on a smooth tire …

Precipitation Of Phosphate Minerals From Effluent Of Anaerobically Digested Swine Manure, Alex Y. Lin

USF Tampa Graduate Theses and Dissertations

Swine production represents approximately 40% of the world's meat production, and its wastes contain high concentrations of organic carbon, nitrogen (N), and phosphorus (P). Anaerobic digestion is an increasingly popular technology for treating animal wastes while simultaneously generating energy. Its propagation and ability to solubilize organic N and P make adding a struvite recovery process attractive. Recovering struvite (MgNH4PO4) from anaerobically digested swine waste can address global P shortages, meet P discharge guidelines, and produce slow-release fertilizer, which can be sold for revenue.

Anaerobic digesters were operated with at organic loading rates of 3.4-3.9 g volatile solids per liter per …

Water's Dependence On Energy: Analysis Of Embodied Energy In Water And Wastewater Systems, Weiwei Mo

USF Tampa Graduate Theses and Dissertations

Water and wastewater treatment is a critical service provided for protecting human health and the environment. Over the past decade, increasing attention has been placed on energy consumption in water and wastewater systems for the following reasons: (1) Water and energy are two interrelated resources. The nexus between water and energy can intensify the crises of fresh water and fossil fuel shortages; (2) The demand of water/wastewater treatment services is expected to continue to increase with increasing population, economic development and land use change in the foreseeable future; and (3) There is a great potential to mitigate energy use in …

Development And Application Of Its Operations Evaluation Models (Itsoems), Gummadavelly Narasimha Murthy

USF Tampa Graduate Theses and Dissertations

Intelligent Transportation Systems (ITS) play an important role in supporting motorists and first responders to handle major incidents, hazmat spills, security measures and other emergency operations. Increasingly, technology advancements and applications are providing invaluable integration opportunities to interconnect safety, maintenance, ITS, traffic operations, facilities, and transportation equipment programs to maximize available resources and achieve efficiency in transportation operations.

This research focuses on one of the prominent ITS devices: Dynamic Message Signs (DMS) operations. Using real time incident management operations data and ITS operations data, an attempt is made to develop ITS Operations Evaluations Models (ITSOEMs) that are capable of quantifying …

Frp Stiffener Efficiency Coefficient For Sbs Shear Strengthening Applications, Hamed Babaizadehroshanfekr

LSU Master's Theses

The use of composite materials such as Fiber Reinforced Polymer (FRP) to strengthen concrete structures has surged during the past two decades as an alternative for conventional methods of structural strengthening and repair. FRP materials are light and relatively easy to install. They are noncorrosive, durable and less vulnerable to environmental conditions in comparison to other construction and retrofitting materials. The knowledge and applications of composites for strengthening steel structures are relatively smaller when compared to concrete strengthening applications. Strengthening-By-Stiffening (SBS) is a new strengthening alternative that was developed at Louisiana State University. SBS has proven to be a practical …

Shear Strength Evaluation Of An Erosional Soil System At Fourchon Beach, Jacques Pierre Boudreaux

LSU Master's Theses

South Louisiana is vanishing. Subsidence due to relative sea level rise with erosion of weak wetland soils together produce devastating rates of land loss for this area. It is believed that high rates of erosion are due to weak strength properties of fine-grained sediments in the beaches, marshes, and other wetlands in coastal Louisiana. Wave action is known to initiate the movement of weak coastal soils in a manner that is related to the difference between the shear stresses applied by waves and the critical shear strength of erosional sediments. Direct shear tests were performed on samples obtained from the …

Determining The Performance Of Breakwaters During High Energy Events: A Case Study Of The Holly Beach Breakwater System, Andrew Keane Woodroof

LSU Master's Theses

Breakwaters have been constructed in many areas along Louisiana’s coastline to protect the shoreline from wave energy and erosion. During normal conditions, these breakwaters can typically be analyzed using traditional empirical methods for emergent breakwaters. However, Louisiana’s coastline is under constant threat from tropical storms and hurricanes, during which breakwaters can frequently become overtopped or submerged systems. Recent studies show that the type of shoreline response to a breakwater system may vary depending on the crest height of the breakwater in relation to the mean water level. Though emergent breakwaters typically induce sediment accretion along the shoreline, studies using laboratory …

The Effects Of Lean Intervention (5s) On Perceived Musculoskeletal Workload And Perceived Hazardous Working Conditions In A Health Center Pharmacy, Jastinder Singh Dhindsa

LSU Master's Theses

The healthcare industry involves a significant level of health and safety risks in various work processes, and healthcare professionals are at risk for work-related musculoskeletal disorders and other health problems. In recent years, Lean has been introduced in healthcare with the goal of eliminating waste and improving efficiency. Lean is also believed to affect the health and safety of workers. The present research studies the effects of Lean (5S) implementation in an acute care pharmacy of a health center. A version of the Dutch Musculoskeletal Questionnaire (DMQ) was used to record the perceived musculoskeletal workload and perceived hazardous working conditions. …

Stabilization Of Very Weak Subgrade Soil With Cementitious Stabilizers, Sanjay Kumar Dhakal

LSU Master's Theses

To evaluate the effect of high moisture content on the performance of weak subgrade soil and improve the engineering properties of weak subgrade soil through using cementitious materials, five different soils that represent range of subgrade soil in Louisiana (based on plasticity indices) were collected and considered in this research study. All tests on raw soils and treated/stabilized soils were performed on the soil laboratory at the Louisiana Transportation Research Center (LTRC). Ordinary Portland cement and hydrated lime were selected in this study to treat/stabilize the subgrade soils depending upon the soil type and plasticity index. The repeated load triaxial …

Fundamental Characterization Of Asphalt Mixtures: Warm Mix Asphalt Technologies In Flexible Pavement Systems, Bhanu Vijay Vallabhu

LSU Master's Theses

Increasing concerns on environment and greenhouse effect, coupled with increased construction prices led to the development of new technologies by the Asphalt industry to produce Asphalt Concrete (AC) pavements. Extensive research is being done to evaluate the impact and performance of these new technologies. Warm Mix Asphalt (WMA) is one of these technologies that allow mixing, production, placing and compaction of asphalt mixes at significantly lower temperatures as compared to the traditional Hot Mix Asphalt (HMA) practice. Lower temperatures result in reduced fuel usage, fume exhausts, greenhouse gas emissions, wear and tear at plants; while enhancing worker health and safety …

Development Of Hydrograph-Based Approach To Modeling Fate And Transport Of Sediment-Borne Bacteria In Lowland Rivers, Bhuban Ghimire

LSU Doctoral Dissertations

Fecal pollution is one of the major factors responsible for water quality impairments of rivers and streams, particularly organic-rich fine-grained lowland streams. While predicting fecal pollution is generally required in the development of water quality restoration plans like Total Maximum Daily Loads, no single model has been widely recognized as an efficient and effective tool for estimating fecal pollution. This dissertation develops a simple yet effective modeling approach, called Hydrograph-based Approach, to bacterial fate and transport modeling in lowland rivers. The new hydrograph-based approach is simple and efficient in terms of its less data requirements as compared with other models. …

Impact Of Lean Production On Workers' Exposure To Risk In Modular Home Building Manufacturing, Joel James

LSU Master's Theses

The construction industry records the highest number of work-related injuries and fatalities in the United States according to the Bureau of Labor Statistics. Workers’ exposure to risk may be affected by implementing Lean concepts. This study describes the effects on worker’s safety environment after a Kaizen event, a Lean tool, conducted in three workstations within a modular home manufacturer: base-framing, sheet-rock hanging, and painting. The effects of Lean on safety hazards at each of the three workstations were determined by conducting a Job Safety Analysis (JSA) before and after each Kaizen. Based on the JSAs a risk assessment tool (questionnaire) …

An Intelligent Computational Approach To The Optimization Of Inventory Policies For Single Company, Qinglin Duan

LSU Master's Theses

This study develops and tests a computational approach for determining optimal inventory policies for single company. The computational approach generally comprises of two major components: a meta-heuristic optimizer and an event-driven inventory evaluation module. Meta-heuristic is a powerful search technique, under the intelligent computational paradigm. The approach is capable of determining optimal inventory policy under various demand patterns regardless their distribution for a variety of inventory items. Two prototypes of perishability are considered: (1) sudden deaths due to disasters and (2) outdating due to expirations. Since every theoretical model is specially designed for a certain type of inventory problem while …

Biofiltration For Treatment Of Gases Contaminanted By Beta-Caryophyllene, Weili Hu

LSU Master's Theses

Fixed-film biological treatment processes, commonly referred to as biofilters, have been applied to successfully treat a wide variety of volatile organic compounds (VOCs) present in air emitted by a wide variety of industrial operations. The ability of biofilters to treat some classes of VOCs, however, has not been well established. In particular, the performance of biofilters treating sesquiterpenes has not been widely studied. In the research described herein, a laboratory-scale biofilter was operated to treat a synthetic waste gas stream containing â-caryophyllene, a sesquiterpene emitted by conifer trees and industrial wood processing operations. An enrichment culture developed in an initial …

Continuum And Crystal Strain Gradient Plasticity With Energetic And Dissipative Length Scales, Danial Faghihi Shahrestani

LSU Doctoral Dissertations

This work, standing as an attempt to understand and mathematically model the small scale materials thermal and mechanical responses by the aid of Materials Science fundamentals, Continuum Solid Mechanics, Misro-scale experimental observations, and Numerical methods. Since conventional continuum plasticity and heat transfer theories, based on the local thermodynamic equilibrium, do not account for the microstructural characteristics of materials, they cannot be used to adequately address the observed mechanical and thermal response of the micro-scale metallic structures. Some of these cases, which are considered in this dissertation, include the dependency of thin films strength on the width of the sample and …

Effects Of Recycled Asphalt Shingle On The Rheological And Molecular Composition Properties Of Asphalt Cement, Saman Salari

LSU Master's Theses

Recycling of asphalt shingles in flexible pavements has received interests in recent years due to economic, environmental, and social reasons. The objective of this study is to introduce a new approach to recycle asphalt shingles in asphalt paving construction in which RAS is ground to ultra-fine sizes and blended with asphalt binder through a wet process. In this method, the ground recycled material is blended with the binder at high temperature prior to mixing with the aggregates. Two unmodified binders that are classified as PG64-22 and PG52-28 were blended with two contrasting sources of RAS, originating from tear-off and manufacturer …

Biodegradation And Distribution Of Crude Oil Sampled At Fourchon Beach, Kendall Ray Lemelle

LSU Master's Theses

This study was developed to determine the distribution and fate of crude oil spilled from the Deepwater Horizon oil rig starting on April 24, 2010. Crude oil from this spill contaminated portions of Fourchon Beach, Louisiana which was the study site for this thesis. Understanding the fate processes that affect crude oil once it’s released is important because the compounds that comprise oil can be hazardous to humans and wildlife. Composite and small surface residual ball (SSRB) samples were collected from the supratidal zone of Fourchon Beach and analyzed for PAHs and alkanes. Alkane concentrations decreased significantly over time, while …

Thermal Field Investigations And Applications To Integral Abutment Bridges With Frp Panels, Bo Kong

LSU Doctoral Dissertations

Expansion joints are often considered as one of the most vulnerable elements affecting the sustainability of traditional jointed bridges. Over the past several decades, a new type of integral abutment bridge (IAB) has been proposed, where the joints are eliminated at the abutments and/or along the length of the bridges. Although with wide acceptances, the IABs have not been largely applied in practice. Many arguments are unsettled and there are no national design guidelines currently. Among all, the thermal behavior is one of the most concerned issues, and that, to a large extent, limits the maximum length of IABs that …

Laboratory Evaluation Of Geosynthetics To Stabilize/Reinforce The Subgrade/Base In Unpaved Roadways, Imran Akond

LSU Master's Theses

This research study evaluates the performance of geosynthetic material for subgrade stabilization and base reinforcement of unpaved test sections. For this purpose, extensive large-scale in-box static plate load tests were conducted on several unreinforced and geosynthetic reinforced, unpaved test sections. This research was conducted in Geotechnical Engineering Research Laboratory (GERL) at Louisiana Transportation Research Center (LTRC). The in-box static plate load tests (ASTM D1196-93) were conducted to evaluate the performance and benefits of geosynthetic material for subgrade stabilization/base reinforcement. A total of forty-seven tests were performed in this regard. The quality control of the section was maintained using non-destructive in-situ …

Thermal Stress Analysis Of Jointed Plain Concrete Pavements Containing Fly Ash And Slag, Yoonseok Chung

LSU Doctoral Dissertations

With the current demand for Portland cement concrete (PCC) sustainability, supplementary cementitious materials (SCMs) are used in concrete mixtures. The SCMs positively impact the environmental and economic aspects of concrete mixtures and improve the mixture properties in both fresh and hardened concrete. In this research, one control and twenty-four ternary mixtures, with various combinations of fly ashes (Class C and F), slags (Grade 100 and 120), and Portland cement were fabricated. The thermal properties (coefficient of thermal expansion (CTE), thermal conductivity, and heat capacity) and mechanical properties of the selected ternary mixtures were measured at various ages. Temperature gradients were …

Microencapsulation Of Self-Healing Concrete Properties, James Gilford Iii

LSU Master's Theses

ABSTRACT Recent studies in the literature have demonstrated the ability of self-healing processes to be effective in enhancing the overall life of concrete. The main goal of this project is to evaluate and to control specific parameters for the production of an effective self-healing matrix that can be utilized within the application of self-healing concrete. Therefore, the project objective is to synthesize microcapsules using dicyclopentadine and sodium silicate and to evaluate the effects of pH, temperature, and agitation rate on microcapsule morphology. The microcapsule diameter, yield analysis, and shell thickness were characterized using scanning electron microscopy. During the experimental analysis, …

Dynamic Route Choice In Hurricane Evacuation, Meisam Akbarzadeh

LSU Doctoral Dissertations

In this research a framework is developed for modeling route choice in hurricane evacuation. Two behavioral hypotheses are evaluated which together with the route choice model, constitute the contributions of the research. The first hypothesis states that beside congestion, other variables such as familiarity with the route, availability of fuel and shelter, facility class, and length of route have an effect on an evacuees' route choice. The second hypothesis states that as time passes and storm conditions change, the impact each variable has on route choice changes. The logit structure was used for modeling the choice process and stated choice …

Efficient Finite Element Modeling Of Reinforced Concrete Columns Confined With Fiber Reinforced Polymers, Dan Hu

LSU Master's Theses

Fiber reinforced polymer (FRP) composites have found extensive applications in the field of Civil Engineering due to their advantageous properties such as high strength-to-weight ratio and high corrosion resistance. This study presents a simple and efficient frame finite element (FE) able to accurately estimate the load-carrying capacity and ductility of reinforced concrete (RC) circular columns confined with externally bonded fiber reinforced polymer (FRP) plates and/or sheets. The proposed FE considers distributed plasticity with fiber-discretization of the cross-sections in the context of a force-based (FB) formulation. The element is able to model collapse due to concrete crushing, reinforcement steel yielding, and …

Growth Rate And Productivity Of A Louisiana Native Microalgae/Cyanobacteria Co-Culture: Feasibility For Use In Industrial Biotechnology Applications, Athens Gomes Silaban

LSU Master's Theses

Interest in biofuels research has increased in the era of uncertainty of the current fossil fuel sustainability and global climate concerns. Microalgae offer advantages over terrestrial plants as a potential source of biomass-based fuel. In this study, a Louisiana native microalgae/cyanobacteria (Chlorella vulgaris/Leptolyngbya sp.) co-culture was examined to provide foundational information of its growth conditions. Batch studies were conducted to determine optimum nitrogen and irradiance level that yields maximum co-culture biomass growth and productivity under aerated and non-aerated conditions. The optimum nitrogen level was 2.94 mM N and the optimum initial scalar irradiance range was between 400 – 800 µmol …