Civil Engineering Commons^™

The Effects Of Notch Geometry On Fracture Testing Of Asphalt Concrete, Rebekah Porter

Civil Engineering Undergraduate Honors Theses

Asphalt concrete is commonly used as the surface layer on pavements because of its convenience, low cost, and smooth ride (Wagoner, 2005). However, there is a significant problem with the cracking and deterioration of asphalt concrete roads. The initiation of cracking in asphalt must be better understood in order to further improve pavement design. Fracture energy is the amount of energy needed to separate two surfaces. The semi circular bend (SCB) test can be used to measure the fracture energy of asphalt concrete. Currently, this method uses a semicircular specimen with a rectangular notch in a three-point bend compression test. …

Maintenance And Improvement Of The Florida Public Hurricane Loss Model, Nicholas Wayne Miller

Theses and Dissertations

The Florida Public Hurricane Loss Model (FPHLM) predicts insurance losses due to hurricane events. This thesis describes maintenance tasks of the vulnerability component of the FPHLM. First, it explores the applicability of recent experimental research to the FPHLM opening protection, water intrusion, and roof pressure modeling features of the Personal Residential (PR) and Commercial Residential Low-Rise (CR-LR.) models. These changes were not implemented because either more experimental data is needed or they had no impact on the losses. Next, it discusses an additional update to the CR-LR model that changed the soffit area calculations, sampling bounds within the rain model, …

Sulfate Resistance Of Nanosilica Contained Portland Cement Mortars, Iani Batilov Batilov

UNLV Theses, Dissertations, Professional Papers, and Capstones

Soils, sea water and ground water high in sulfates are commonly encountered hostile environments that can attack the structure of concrete via chemical and physical mechanisms which can lead to costly repairs or replacement. Sulfate attack is a slow acting deteriorative phenomenon that can result in cracking, spalling, expansion, increased permeability, paste-to-aggregate bond loss, paste softening, strength loss, and ultimately, progressive failure of concrete. In the presented research study, Portland cement (PC) mortars containing 1.5% to 6.0% nanosilica (nS) cement replacement by weight were tested for sulfate resistance through full submersion in sodium sulfate to simulate external sulfate attack. Mortars …

Occurrence And Proliferation Of Antibiotics And Antibiotic Resistance In Wastewater Treatment Plants, Majid Neyestani

UNLV Theses, Dissertations, Professional Papers, and Capstones

Solids retention time (SRT) is one of the most important factors in designing and operating activated sludge systems for biological wastewater treatment. Longer SRTs have been shown to alter the structure and function of microbial communities, thereby leading to improved treatment efficacy with respect to bulk and trace organics, nutrient removal, and membrane fouling. However, research has also shown that longer SRTs lead to increased prevalence of antibiotic resistant bacteria, perhaps due to increased exposure to antibiotics present in influent wastewater. The purpose of this study was to characterize changes in microbial community structure in a laboratory-scale activated sludge system …

Alkali-Activated Natural Pozzolan/Slag Binder For Sustainable Concrete, Meysam Najimi

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study aimed to fully replace Portland cement (PC) with environmentally friendly binders capable of improving longevity of concrete. The new binders consisted of different proportions of natural Pozzolan and slag which were alkaline-activated with various combinations of sodium hydroxide and sodium silicate. A step-by-step research program was designed to (1) develop alkali-activated natural Pozzolan/slag pastes with adequate fresh and strength properties, (2) produce alkali-activated natural Pozzolan/slag mortars to assess the effects of dominant variables on their plastic and hardened properties, and (3) finally produce and assess fresh, mechanical, dimensional, transport and durability properties of alkali-activated natural Pozzolan/slag concretes. The …

Causes And Impacts Of Geotechnical Problems On Bridge And Road Construction Projects, Krishna Prasad Neupane

UNLV Theses, Dissertations, Professional Papers, and Capstones

Changes during the construction phase generate cost growth, schedule delays, and claims in any project. However, the impact of geotechnical problems on construction costs, schedules, and claims in bridge and road projects had not been investigated in depth. The major objectives of this study were to determine the geotechnical-related causes of cost and schedule growth and claims as well as their impacts on the bridge and pavement projects’ performance. This study also identifies mitigation measures to avoid cost and schedule growth and claims in these projects.

A survey was conducted with 53 engineers from state Department of Transportations (DOTs) and …

Feasibility Study Of Using Recyclable Polyethylene (Pet) Materials As Coarse Aggregate For Concrete Mixtures, Philip M. Angelo

Construction Management

The feasibility of using recyclable household plastics, specifically those made of polyethylene, commonly used in water and soda bottles, as a replacement for concrete coarse aggregate, was assessed. A method was developed for cutting polyethylene materials into fibrous strips. These strips were then used as a replacement for the rock coarse aggregate in batches of concrete. Standard 6” x 12” test cylinders were made using the concrete mixture and subject to destructive compressive testing in order to yield the compressive strength of the concrete mix 7, 14, 21, and 28 days after pouring. Three mixtures were tested, one control with …

An Assessment Of Post-Encroachment Times For Bicycle-Vehicle Interactions Observed In The Field, A Driving Simulator, And In Traffic Simulation Models, Ali Razmpa

Dissertations and Theses

Most safety analysis is conducted using crash data. Surrogate safety measures, such as various time-based measures of time-to-collision can be related to crash potential and used to gain insight into the frequency and severity of crashes at a specific location. One of the most common and acknowledged measures is post-encroachment time (PET) which defines the time between vehicles occupying a conflicting space. While commonly used in studies of motor vehicle interactions, studies of PET for bicycle-vehicle interactions are few. In this research, the PET of bicycle-vehicle interactions measured in the field, a driving simulator, and in a micro-simulation are compared. …

Experimental Investigation Of Cfrp Wrapped Square Non-Ductile Reinforced Concrete Columns, Hayder Lateef Al-Khafaji

Dissertations and Theses

The use of fiber-reinforced polymers (FRP) for retrofitting or strengthening deficient concrete columns noticeably increased in the past few decades. Plenty of research has been conducted on the behavior of FRP-strengthened circular concrete columns, but far less research has dealt with non-circular columns. In the current study, the focus was to investigate the behavior of square columns with low to medium grade concrete and low steel reinforcement that were strengthened using carbon fiber reinforced polymer (CFRP) wrap. In the experimental portion of this investigation, twelve short square reinforced concrete columns (5" x 5" in cross section and 12" high) were …

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 …

Investigation Of Self-Organizing Traffic Signal Control With Graphical Signal Performance Measures, Christopher M. Day, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

Adaptive signal control is the subject of an increasing amount of research, as well as development and implementation. Most existing adaptive control systems achieve coordination by applying system control as a constraining layer on top of local control. Some researchers have suggested that, with the right local-control logic, coordination might be achieved as an dynamically emergent phenomenon without the need for a management layer. This paper explores the potential of a self-organizing signal control algorithm using a variety of performance measures. First, the initially reported algorithm performance is reproduced in an idealized environment; next, the algorithm is applied in a …

Characteristics And Products Of The Reductive Degradation Of 3-Nitro-1,2,4-Triazol-5-One (Nto) And 2,4-Dinitroanisole (Dnan) In A Fe-Cu Bimetal System, Elsie Kitcher, Washington Braida, Agamemnon Koutsospyros, Julius Pavlov, Tsang-Liang Su

Civil Engineering Faculty Publications

It has been shown previously that, under acidic conditions, 3-nitro-1,2,4-triazol-5-one (NTO) and 2,4-dinitroanisole (DNAN) degrade in the presence of iron/copper bimetal particles; the reactions can be modeled by pseudo-first-order kinetics. This study investigates the reaction mechanisms of the degradation processes under different conditions. Batch studies were conducted using laboratory-prepared solutions and an industrial insensitive munition-laden (IMX) wastewater. The influence of parameters such as initial pH of the solution, copper/iron (Fe-Cu) contact, and solid/liquid ratio were systematically investigated to assess their impact on the reaction kinetics. These parameters were subsequently incorporated into pseudo-first-order decomposition models for NTO and DNAN. The activation …

Scalable Dashboard For Identifying Split Failures And Heuristic For Reallocating Split Times, Howell Li, Lucy Richardson, Christopher M. Day, James Howard, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

The three fundamental parameters of a traffic signal system are split, cycle, and offset. This paper describes the use of high-resolution data (a) to identify time periods during which split parameters may be insufficient and (b) to help practitioners identify opportunities for reallocating split time. A case study of seven corridors with 47 intersections is presented. A drill-down approach was developed to identify movements that could be improved by a reallocation of split times. A heuristic that can reallocate up to 5 seconds of underutilized green time on a competing phase was applied to those corridors. …

Detector-Free Optimization Of Traffic Signal Offsets With Connected Vehicle Data, Cristopher Day, Howell Li, Lucy Richardson, James Howard, Tom Platte, Jim Sturdevant, Darcy M. Bullock

Lyles School of Civil Engineering Faculty Publications

It has recently been shown that signal offset optimization is feasible using vehicle trajectory data at low levels of market penetration. This study performs offset optimization on two corridors using this type ofdata. Six weeks oftrajectory splines were processed for two corridors including 25 signalized intersections, in order to create vehicle arrival profiles, using a proposed procedure called "virtual detection." After processing and filtering the data, penetration rates between 0.09-0.80% were observed, varying by approach. The arrival profiles were statistically compared against those measured with physical detectors, with the majority of the approaches showing statistically significant goodness-of-fit at a 90% …

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 …

Simulation Of Value Stream Mapping And Discrete Optimization Of Energy Consumption In Modular Construction, Md Mukul Chowdhury

Theses and Dissertations

With the increased practice of modularization and prefabrication, the construction industry gained the benefits of quality management, improved completion time, reduced site disruption and vehicular traffic, and improved overall safety and security. Whereas industrialized construction methods, such as modular and manufactured buildings, have evolved over decades, core techniques used in prefabrication plants vary only slightly from those employed in traditional site-built construction. With a focus on energy and cost efficient modular construction, this research presents the development of a simulation, measurement and optimization system for energy consumption in the manufacturing process of modular construction. The system is based on Lean …

Understanding The Behavior Of Embankment Dams Under Blast Loading, Courtney L. Busch

Civil Engineering ETDs

This purpose of this study is to investigate the deformation-induced stability of earthen embankment dams to explosive airblast loading. This study specifically investigated the effects of close-in explosive airblast loads on the downstream toe of a homogeneous earthen embankment dam composed of cohesive soils. Small-scale explosive airblast experiments were performed on cohesive soils to obtain an experimental data set with which to compare numerical analyses. Experimental measurements included crater geometry, ground vibration energy, and air overpressure from the blast events. Laboratory tests were conducted on the experiment soils to obtain engineering properties including shear strength and compressibility indices. Finite element …

Pyrolysis Of Wastewater Biosolids Significantly Reduces Estrogenicity, T. C. Hoffman, Daniel Zitomer, Patrick J. Mcnamara

Civil and Environmental Engineering Faculty Research and Publications

Most wastewater treatment processes are not specifically designed to remove micropollutants. Many micropollutants are hydrophobic so they remain in the biosolids and are discharged to the environment through land-application of biosolids. Micropollutants encompass a broad range of organic chemicals, including estrogenic compounds (natural and synthetic) that reside in the environment, a.k.a. environmental estrogens. Public concern over land application of biosolids stemming from the occurrence of micropollutants hampers the value of biosolids which are important to wastewater treatment plants as a valuable by-product. This research evaluated pyrolysis, the partial decomposition of organic material in an oxygen-deprived system under high temperatures, as …

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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Bridge End Settlement Evaluation And Prediction, Jiwen Zhang, Timothy R. Taylor, Roy E. Sturgill

Kentucky Transportation Center Research Report

A bridge approach is usually built to provide a smooth and safe transition for vehicles from the roadway pavement to the bridge structure. However, differential settlement between the roadway pavement that rests on embankment fill and the bridge abutment built on more rigid foundation often creates a bump in the roadway. Previous work examined this issue at a microscopic level and presented new methods for eliminating or minimizing the effects at specific locations.

This research studies the problem at a macroscopic level by determining methods to predict settlement severity; this assists designers in developing remediation plans during project development to …

Assessment Of Shear Prediction Models For Seismic Loss Estimation Of Concrete Buildings, Bashir Mohamed Ayman Al Murad

Civil and Environmental Theses

No abstract provided.

Modeling Factors Contributing To Injury And Fatality Of Run-Off-Road Crashes In Ohio, Deogratias Eustace, Omar Eid Almutairi, Peter W. Hovey

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

The main objective of this study was to determine the factors that contribute significantly to the levels of injury severity when run-off-road (ROR) crashes occur. This study used a 5-year crash data for years 2008 - 2012 from the state of Ohio. The decision tree model in conjunction with generalized ordered logit model was used to investigate characteristics of injury and fatality of run-off-road crashes in Ohio.

The decision tree modeling was used for exploratory data analysis identified eight factors that explain a large amount of the variation in the response variable, injury severity. These predictor variables include road condition, …

Altered Antibiotic Tolerance In Anaerobic Digesters Acclimated To Triclosan Or Triclocarban, Daniel Elliott Carey, Patrick J. Mcnamara

Civil and Environmental Engineering Faculty Research and Publications

Bench-scale anaerobic digesters were amended to elevated steady-state concentrations of triclosan (850 mg/kg) and triclocarban (150 mg/kg) using a synthetic feed. After more than 9 solids retention time (SRT) values of acclimatization, biomass from each digester (and a control digester that received no antimicrobials) was used to assess the toxicity of three antibiotics. Methane production rate was measured as a surrogate for activity in microcosms that received doses of antibiotics ranging from no-antibiotic to inhibitory concentrations. Biomass amended with triclocarban was more sensitive to tetracycline compared to the control indicating synergistic inhibitory effects between this antibiotic and triclocarban. In contrast, …

Anaerobic Digester Bioaugmentation Influences Quasi Steady State Performance And Microbial Community, Kaushik Venkiteshwaran, K. Milferstedt, J. Hamelin, Daniel Zitomer

Civil and Environmental Engineering Faculty Research and Publications

Nine anaerobic digesters, each seeded with biomass from a different source, were operated identically and their quasi steady state function was compared. Subsequently, digesters were bioaugmented with a methanogenic culture previously shown to increase specific methanogenic activity. Before bioaugmentation, different seed biomass resulted in different quasi steady state function, with digesters clustering into three groups distinguished by methane (CH₄) production. Digesters with similar functional performance contained similar archaeal communities based on clustering of Illumina sequence data of the V4V5 region of the 16S rRNA gene. High CH₄ production correlated with neutral pH and high Methanosarcina abundance, whereas …

How Acoustics In California High Performance Schools Relate To Student Achievement, Devin K. Wong

Durham School of Architectural Engineering and Construction: Dissertations, Theses, and Student Research

This research project seeks to determine if students attending K–12 schools meeting a minimum standard of high performance classroom conditions in the state of California do evidence higher scholastic achievement, based on publically available results on state-wide standardized tests. In three phases, a subset of 200+ schools applying for grants dedicated to building high performance schools over the past decade was correlated with an existing database of achievement scores for all public schools in California. The criteria utilized to specify high performance classrooms was provided by the California High Performance Initiative (HPI) Grant program. Academic achievement was evaluated on a …

Evaluating Soil Properties And Cyclic Loading Effects Of Florida’S Clayey Silty Fine Sand Soils Associated With High Pile Rebound, Ali Fadil M. Omar

Theses and Dissertations

Throughout the state of Florida, pile rebound has been encountered while driving large displacement piles. During periods of excessive rebound, the piles could not achieve further penetration and could require an excessive number of blows to advance the pile into the ground. This phenomenon affecting pile driving is called high pile rebound producing construction delays, higher costs; and may lead to pile damage. A comprehensive experimental program was performed involving the characterization and identifications of the typical soils properties associated with high pile rebound during pile installation. The research focuses on the determination of the relationships between high and no-rebound …

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 …

Beams, Bobby (Fa 955), Manuscripts & Folklife Archives

Folklife Archives Finding Aids

Finding aid only for Folklife Archives Project 955. Paper titled: “Sawmills Past and Present in Hart, southern LaRue, and western Green County.” Includes description, terms, illustration, and photos of sawmills in the Penny Royal Region of Kentucky.

Powers, Doug (Fa 954), Manuscripts & Folklife Archives

Folklife Archives Finding Aids

Finding aid only for Folklife Archives Project 954. Paper titled: “Montgomery’s Mill.” Includes description, terms illustration, and photos of Montgomery’s Mill in Green County, Kentucky.