Engineering Commons^™

Spatial Variation In Fine Sediment And Microbial Transport Along Stream Cross Sections: Implications To Modeling And Monitoring, Thomas Michael Walton

Masters Theses

Spatial variations in suspended concentrations of fine sediment and indicator bacteria in streams is noted as a source of uncertainty in various applications of water quality datasets. Without proper analysis of the persistence and reasoning for this variance in natural systems, a finer resolution of model calibration is necessary to account for spatial variation in stream cross sections. This level of calibration has become of utmost importance due to technological advancements presenting the ability for water quality modeling frameworks to generate a much finer resolution of outputs. While the importance of model calibration has been noted for remediating levels of …

Effect Of Particle Morphology On The Deformation Behavior Of Sand Under Monotonic Loading Conditions, Alexia Rose Leib

Masters Theses

When a projectile hits sand, the projectile places high stresses on the sand surface. Granular materials at high stresses are liable to crushing. The pressure at which crushing occurs depends greatly on particle shape and relative density. These parameters also greatly influence the changes in particle shape and size after crushing. Additionally, projectiles fired at extremely high velocities are preceded by a pressure wave. This pressure wave can crush granular material before the projectile ever touches the surface. If the sand has been crushed and its inherent particle properties changed before projectile impact, the projectile may not behave as expected. …

Bankfull Geomorphic Relationships And Hec-Ras Assessment In Small Catchments Of The Cumberland Plateau Ecoregion, Ryan Lee Hodges

Masters Theses

There is a great need for state governments to have effective watershed restoration and mitigation efforts to return degraded ecosystems to a stable, healthy condition. Given the growing investment in stream restoration efforts, there is an urgent need for tools to assess and improve the effectiveness of restoration efforts at local, state, and nationwide scales. In 2000 there was less than ten stream restoration permits provided by the state of Tennessee and has increased each year with almost forty permits issued in 2013. To better achieve successful stream restoration, appropriate channel designs must be used that reflect the hydraulic conditions …

The Economic Implications Of Evolving Aviation Funding Policy In Tennessee, Hunter Pressley Mccracken

Masters Theses

The majority of state funding for capital improvements at Tennessee’s general aviation and commercial airports comes through grants awarded from the Tennessee Transportation Equity Trust Fund (TETF). Through a 4.5 percent sales and use tax on the consumption of aviation fuel, users help to fund the continued improvement and maintenance of aviation facilities around the state. Aircraft refueling operations associated with the FedEx “SuperHub” in Memphis were responsible for two-thirds of the TETF’s revenue for Fiscal Year 2014. In response to speculation that FedEx would relocate its refueling operations to reduce its fuel tax liability, the Tennessee General Assembly passed …

Removal Of Trace Organic Compounds In Domestic Wastewater Using Recirculating Packed-Bed Media Filters, Brittani Nikole Perez

Masters Theses

Pharmaceuticals and personal care products (PPCPs) are commonly detected in the environment resulting from their survival from conventional wastewater treatment systems. More information is needed about the fate and transfer of these trace organic compounds in domestic wastewater and their associated risks so that efficient strategies for their removal can be developed for both large/small scale treatment systems. This study aimed to determine whether onsite wastewater treatment systems were capable of providing PPCP removal, in addition to quantifying different forms of removal (biodegradation/sorption). A column study was constructed to determine the removal efficiencies of 3 target PPCPs, endocrine disrupting compound …

Modeling Route Choice Of Utilitarian Bikeshare Users From Gps Data, Ranjit Khatri

Masters Theses

This research examines the behavior of bikeshare users from Grid Bikeshare Program in Phoenix, Arizona under two behavioral frameworks: facility usage assessment and route choice assessment. The analysis is performed for the two different categories of subscribers: registered and casual subscribers. This is the first study that uses the real-time GPS data from bikeshare users to model their route preferences. The data used for this study were obtained from 9,101 trips made by 1,866 bikeshare. An important aspect of this bikeshare is that it allows non-station origin and destinations. The GPS points collected from the trips made by bikeshare users …

Non-Residential Pedestrian Access To Transit Systems: A Gis Modeling Application, Luis Miguel Taboada

Masters Theses

The success of a city’s urban transit system relies on the efficacy of its pedestrian infrastructure. A functional and access-oriented pedestrian network translates into safer pedestrian travel, increased demand in transit ridership, increases in commerce patronage, and reduced motorized travel (i.e., less congestion, and less vehicle emissions). Prioritization and allocation of sidewalk construction improvements are not always done in conjunction with transit service provisions. As a result, potential destinations are left inaccessible to pedestrians using the transit system. This study is motivated by concurrent research involving sidewalk improvement prioritization methods, within the scope of home-based work pedestrian transit trips. This …

A Real-Time Signal Control System To Minimize Emissions At Isolated Intersections, Farnoush Khalighi

Masters Theses

Continuous transportation demand growth in recent years has led to many traffic issues in urban areas. Among the most challenging ones are traffic congestion and the associated vehicular emissions. Efficient design of traffic signal control systems can be a promising approach to address these problems. This research develops a real-time signal control system, which optimizes signal timings at an under-saturated isolated intersection by minimizing total vehicular emissions. A combination of previously introduced analytical models based on traffic flow theory has been used. These models are able to estimate time spent per driving mode (i.e., time spent accelerating, decelerating, cruising, and …

Development Of Prototypes Of A Portable Road Weather Information System, Meha Kainth

Masters Theses

Weather conditions have significant impact on road safety and roadway maintenance operations. Road Weather Information Systems (RWIS) play a significant role in providing weather and surface conditions to transportation agencies to monitor weather events. Fixed installations of RWIS are used for weather and pavement surface monitoring. However, permanent fixture installations may not be feasible due to reasons such as cost, accessibility to the site, siting concerns, and terrain. Portable RWIS provide a cost-effective solution in areas where permanent weather station installation is not possible. This study discusses use and benefits of the portable RWIS and outlines the issues involved in …

Durability Of Lightweight Concrete For Bridge Decks, Andrew Mccullough Wagner

Masters Theses

As concrete durability becomes a higher priority for departments of transportation’s acceptability of concrete for bridge decks, consideration of resistance to the penetration of chloride ions has become a key consideration in defining durability. For years the “Rapid Chloride Ion Penetration (RCP) test has been the accepted standard to measure penetrability of concrete to chloride ions. With the movement to use chloride ion penetrability as a part of acceptance criteria for a concrete mix, use of the newer and easier Surface Resistivity (SR) test as an alternative to the slower, more complicated “Rapid Chloride Ion” test became a desirable option. …

Evaluation Of The Safety Effectiveness Of Clearview Font And Fluorescent Yellow Sheeting On Michigan Freeways And Non-Freeways, Lusanni Mercedes Acosta Rodrieuez

Masters Theses

Halation or irradiation makes guide sign fonts difficult to read. Missing the necessary guide sign information causes anxiety and confusion to drivers, and hence may lead to crashes. In order to avoid or mitigate the situation a newer font, Clearview, is used to provide better readability at long distances. In a similar context the lack of brightness in sheeting material for warning signs reduces conspicuity of sings. Installation of fluorescent yellow sheeting has been done to provide signs with more noticeable and brighter materials. This observational before and after study is an evaluation of the safety and economic benefits of …

Modeling Water Age And Disinfection Byproduct Formation In Drinking Water Distribution Systems In East Tennessee, Seth Adam Fischer

Masters Theses

Chlorine disinfection of drinking waters is responsible for the standard of health we enjoy today and the eradication of waterborne disease. Chlorine also reacts with natural organic matter (NOM) to form disinfection byproducts (DBPs) which have been linked to cancer as well as reproductive and developmental issues. The exact mechanism for formation of regulated DBPs, trihalomethanes (THMs) and haloacetic acids (HAAs), is unknown. The literature has identified relationships between DBP formation and, most notably, characteristics of NOM, chlorine contact time, temperature, pH [negative log of hydrogen ion concentration], and chlorine dose. This study develops models both specific to individual utilities, …

Modeling Water Quality For Switchgrass Crop Production: Implications For Bioenergy Sustainability In East Tennessee, Zachariah Tzvi Seiden

Masters Theses

With passing of the US Energy Independence and Security Act (EISA) of 2007, there has been considerable research conducted on the sustainability of bioenergy crop production in the United States; switchgrass has shown particular potential for bioenergy production in East Tennessee. Many studies evaluating the environmental impact switchgrass has on runoff and water quality use the Soil and Water Assessment Tool (SWAT) for watershed modeling. Because SWAT is a lumped watershed model, it evaluates the result of hydrological processes for each hydrologic response unit (HRU), without accounting for the physical interactions between these HRUs. The Water Erosion Prediction Project (WEPP) …

Bonded Anchors In Concrete Under Sustained Loading, Douglas Droesch

Masters Theses

Post installed anchors come in either mechanical anchors that develop their strength purely through mechanical interlock with the base concrete, or bonded anchors that develop their strength by bonding anchor rod to the base concrete. Bonded anchors are either grouted, typically cementitious material, or adhesive, typically a chemical material. This thesis presents a current literature review of post-installed bonded anchors, preliminary testing of adhesive bonded anchors, and details of short term and long term test setups for future testing. The purpose of this thesis was to develop the test setups that will be used for future testing on anchors.

Fragility Assessment Of High-Rise Reinforced Concrete Buildings, Hezha Sadraddin

Masters Theses

This research presents a probabilistic seismic responses analysis of high-rise reinforced concrete (RC) buildings using fragility assessment method. Three RC buildings, having the same plan dimension and height (12 story each) but different in structural configurations, were designed and their seismic responses were compared. First building is a Moment Resisting Frame (MRF), second is a MRF with exterior shear walls, and the third building consists most shear walls. Buildings were designed for high-seismic activity zone (i.e. Los Anglos) using the Equivalent Lateral Force (ELF) for seismic loading calculation. Sixteen real ground motion pairs were selected and scaled, then applied orthogonally …

A Microscopic Simulation Approach To Performance Evaluation Of Intelligent Transportation System Corridors: A Case In Michigan, Matthew Levi Clark

Masters Theses

A cost and benefit evaluation of the Michigan Department of Transportation’s (MDOT) Intelligent Transportation Systems (ITS) is performed through integration of analytical techniques and microscopic traffic microsimulation. Observed freeway corridor incident logs and characteristics are studied to determine representative incident management patterns on choice study corridors. The Quadstone Paramics microsimulation traffic package is used to model the selected corridors during various analysis scenarios and investigate the effects of ITS on freeway incident management performance.

Design And Construction Of A Full-Scale Lateral Impact Testing Facility, Cody Aaron Mitchell

Masters Theses

The goal of this work is to design and construct a full scale lateral impact testing facility that is capable of recreating the damage that would be created by an overheight vehicle collision. This was accomplished by impacting a test specimen with an 8000 lbs. impact cart. The impact cart is raised on an elevated track and allowed to roll down the track with a change in height of 10 ft. This change in height is what provides the impact force necessary to recreate an overheight vehicle collision. The track is constructed out of wood and is designed to withstand …

Integrating Engineering And Social Aspects In Selecting Stormwater Control Measures (Scms), Maudy Indriani Budipradigdo

Masters Theses

The Low Impact Development (LID) approach to stormwater management is rapidly becoming the required replacement for the traditional approach of development design, solely for peak runoff attenuation. Stormwater Control Measures (SCMs) used in LID designs are some combination of physical structures and /or agronomic practices designed to capture runoff, remove pollutants, promote groundwater recharge, and protect receiving streams from channel degradation. The LID approach has been studied and documented in many journals and design manuals, but we know of no comprehensive study that combines the engineering (hydrologic performance requirements) and social aspects (complementary requirements) of the approach. SCMs have historically …

Modeling Of Debonding And Crack Propagation In Fibrous Composites Using A Discontinuous Galerkin Approach, Wesley Michael Hicks

Masters Theses

A recently proposed Discontinuous Galerkin (DG) method for modeling debonding and fracture within the context of the finite element method is investigated for problems relating to fiber reinforced composites, namely fiber-matrix interfacial debonding which progresses to matrix fracture. The results are then compared against an existing intrinsic cohesive zone method and a hybrid Discontinuous Galerkin method. The results show that the method can eliminate the problem of artificial compliance that is associated with intrinsic cohesive zone models. Eliminating this stiffness has the positive effect of removing user-defined numerical parameters that are not actually present in the physical system. A key …

Resilience Of Transportation Infrastructure Systems To Climatic Extreme Events, Alexandra C. Testa

Masters Theses

A topology-based approach has been used to measure the resilience of a highway network to climatic events. Civil infrastructure systems are inarguably critical to the everyday functions of society. Because such systems are regionally distributed, their components undergo a wide range of hazard intensities, often dependent on their relative locations. The ability of an infrastructure system to withstand, adapt to, and rapidly recover from extreme events is paramount to its ability to continuously serve users. The topological properties of a network can provide a good means to assess the resilience of the system which is adequate to comprehend the preparedness …

Structural Vulnerability Assessment Of Bridge Piers In The Event Of Barge Collision, David A. Ribbans

Masters Theses

The inland waterway system in the United States is fundamental to the transportation system as a whole and the success of the nation’s economy. Barge transportation in these waterways levitates congestion on the highway system and is beneficial when comparing barge transportation to other modes of freight transportation in measures of capacity, congestion, emissions, and safety. Unavoidably, the highway system intersects with the waterways, resulting in the risk of vessels collision into bridge structures. Particularly for barge impact, the literature is questioning the accuracy and oversimplification of the current design specifications.

The impact problem was investigated in this research using …

Driver Behavior Evaluation Of Variable Speed Limits And A Conceptual Framework For Optimal Vsl Location Identification, Curt P. Harrington

Masters Theses

Static speed limits are the norm across the world’s roadway networks. However, advances in technology and increased applications in intelligent transportation systems (ITS) provide a mechanism for upgrading traditional speed limits into an active traffic management system. More specifically, variable speed limits (VSLs) can be used in high crash severity locations and in real-time congestion and weather events to increase traffic safety and operations. Much of the available literature on VSLs focuses upon crash prediction algorithms for VSLs, simulations, and effectiveness of real-world VSL implementations. One noticeable gap in the existing literature is related to driver compliance under varied configurations …

Nano-Scale Investigation Of Mechanical Characteristics Of Main Phases Of Hydrated Cement Paste, Shahin Hajilar

Masters Theses

Hydrated cement paste (HCP), which is present in various cement-based materials, includes a number of constituents with distinct nano-structures. The elastic properties of the HCP crystals are calculated using molecular dynamics (MD) methods. The accuracy of estimated values is verified by comparing them with the results from experimental tests and other atomistic simulation methods. The outcome of MD simulations is then extended to predict the elastic properties of the C-S-H gel by rescaling the values calculated for the individual crystals. To take into account the contribution of porosity, a detailed microporomechanics study is conducted on low- and high-density types of …

Measuring The Resilience Of Transportation Networks Subject To Seismic Risk, Mark N. Furtado

Masters Theses

Transportation networks are critical to the function of modern society but they are vulnerable to extreme events such as earthquakes. Damaged bridges can cost millions of dollars to repair and congestion and detours due to bridge closures leads to indirect costs that are even greater than the cost of repair of damaged bridges. A resilient network however should be able to limit the damage caused by earthquakes and recover in a timely fashion. Resilience of networks has been studying in length from a conceptual standpoint but as quantitative measure, the field has been lacking. This study sets forth to quantify …

An Observational Evaluation Of Safety Resulting From Driver Distraction, Christina M. Dube

Masters Theses

Distracted driving is a dangerous activity that continues to claim lives on roadways throughout the United States. A goal of this research was to collect distracted driving behavior data through observation in the field. A methodological approach was devised to keep data collection consistent across the observation periods. Analysis of the data provided information regarding trends in distraction type or driving behavior while engaging in a secondary activity. In combination with the observational portion of this research, another key component to understanding distracted driving was the crash report narrative key word search. By searching through the crash reports, it was …

Comprehensive Benefits Of Green Roofs, Madison R. Gibler

Masters Theses

"Green infrastructure uses vegetation, soils, and natural processes to manage water and create healthier urban environments, providing traditional roof services and alternative stormwater management technologies. Other benefits and impacts are not yet fully understood or valued. Research conducted assesses specific stormwater benefits of green roofs, providing information on nutrient leaching from media; and analyzes potential energy benefits through side-by-side comparisons of full-scale white, traditional black rubber, and green roofs in the mid-continent Missouri climate. Roofing media selection impacted leaching of nutrients, suspended solids, and organic carbon from the tested green roof media. Thermal properties were investigated at the building level, …

Shear-Friction Of Sand-Lightweight Clay And Slate Aggregate Concretes With Varied Reinforcement Ratios, Samantha Lynn Wermager

Masters Theses

"This thesis focuses on the structural properties of sand-lightweight aggregate concrete in terms of shear transfer strength at cold-joint interfaces. This type of interface is common for precast concrete connections which are typically designed using the shear-friction concept. This testing program was meant to expand the shear-friction database and evaluate the appropriateness of current shear-friction design provisions with respect to sand-lightweight concrete. This study builds on the work done by Shaw (2013) who studied lightweight expanded shale aggregate concrete. The current study included thirty-two push-off specimens constructed from sand-lightweight concrete with a target compressive strength of 5,000 psi. Either expanded …

Characterizing The Influence Of Carbon On The Flowrate And Disinfection Efficacy Of Household Ceramic Water Filters, Jessie Yvonne Hahn

Masters Theses

"Drinking water contamination is a major cause of disease in developing countries. Point of Use (POU) water treatment technologies generally have low initial cost and allow rapid availability of improved water. Ceramic pot filters (CPFs) are a POU water source treatment technology which filter water by gravity through a porous ceramic media. Some filters in use contain carbon remnants left from the fugitive pore former as a dark carbon core. Using disk-shaped experimental ceramic filters produced in the lab to have varying levels of carbon, the percent carbon present was measured and a visual analysis method was developed to determine …

Behavior Of Crimped Cold-Formed Steel C-Section Beams, Jeffrey Devon Smith

Masters Theses

"This work covers the behavior of crimped cold-formed steel C-section beams under flexural loading. The specific beam shape that was tested was 600S162-54. The crimps were placed in the flange and web of the beam to curve the beam. Three crimp sizes were tested: 0.5 degree, 1.5 degree, and 3.0 degree. In construction practice, the company placed a reinforcing steel band that overlapped the crimped areas to restore strength. These various crimp degrees were tested to evaluate how much strength, if any, was lost. The reinforcing steel band was tested simultaneously with the beam to evaluate if its presence significantly …

3d Numerical Modelling Of Micropiles Interaction With Soil & Rock, Audai Kamal Theinat

Masters Theses

"A 5-span bridge along the Foothills Parkway of the Great Smoky Mountains, TN, was recently completed. Two out of the four piers were instrumented to measure the load transfer in the foundations. The foundations consisted of twenty 10-inch micropiles under the pile cap for each pier. Strain gages were installed and monitored at the different stages of construction. The objective of this research is to examine the interaction between the ground and micropiles using the field data performance and numerical modelling. The 3D computer model consists of the micropile foundation within the steep rock bedding planes and overburden soils. The …