Engineering Commons^™

Rural To Urban Intercity Transit User Characteristics Analysis, Demand Estimation And Network Design, Hongtai Yang

Doctoral Dissertations

Rural transit always plays a critical role in transporting rural residents, especially the ones who do not have a car, cannot drive, or choose not to drive. Intercity bus (ICB), deviated fixed route transit (DFRT) and demand responsive transit (DRT) are three major modes of rural public transportation. Although there are more DFRT and DRT service providers and services in the US, due to institutional issues, there are much more studies about ICB than DFRT and DRT. Meanwhile, state governments are struggling on how to improve the rural transit system with limited budget. This dissertation is aimed to fill the …

Bedload Transport Sampling, Characterization And Modeling On A Southern Appalachian Ridge And Valley Stream, Patrick Lasater Mcmahon

Doctoral Dissertations

Estimates of bedload transport rates developed from existing transport models are notoriously inaccurate(Wilcock 2001). The gravel bed models addressed in this study include the Meyer-Peter and Muller; Parker, Klingeman, and McLean; and Wilcock two-fraction models. The question of whether or not these models predict bedload transport rates in a Southern Appalachian Ridge and Valley stream is complicated by the fact that these models have only been previously assessed in terms of their agreement with bedload transport rates measured in the Western regions of the U.S. Further, due to the strongly non-linear form of bedload transport models discrete errors and cumulative …

Effects Of Data Resolution And Human Behavior On Large Scale Evacuation Simulations, Wei Lu

Doctoral Dissertations

Traffic Analysis Zones (TAZ) based macroscopic simulation studies are mostly applied in evacuation planning and operation areas. The large size in TAZ and aggregated information of macroscopic simulation underestimate the real evacuation performance. To take advantage of the high resolution demographic data LandScan USA (the zone size is much smaller than TAZ) and agent-based microscopic traffic simulation models, many new problems appeared and novel solutions are needed. A series of studies are conducted using LandScan USA Population Cells (LPC) data for evacuation assignments with different network configurations, travel demand models, and travelers’ compliance behavior.

First, a new Multiple-Source-Nearest-Destination Shortest Path …

Investigation Of Asphalt Pavement Mixture Blending Utilizing Analytical Chemistry Techniques, Benjamin Frank Bowers

Doctoral Dissertations

The use of Reclaimed Asphalt Pavement (RAP) in new pavement mixtures is a topic of interest throughout the transportation industry and academia due its economic and environmental implications. There is concern however about how well the binder from the RAP blends with new, virgin binder when the mixture is created. Insufficient blending of the aged and unaged binders may compromise the long-term pavement performance. In this study, an enhanced staged extraction method is coupled with two chemical testing techniques to develop a novel approach for evaluating blending efficiency from a qualitative and quantitative perspective: Gel Permeation Chromatography (GPC) and Fourier …

A Framework To Predict High Risk Roadways For Pedestrians In Tennessee, Zane Hunter Pannell

Masters Theses

Pedestrians and bicyclists are a class of vulnerable road users that are often over-represented in incapacitating injury or fatal crash statistics. Because non-motorized trips are vital to many urban and rural residents for utility or recreation and exercise, it is essential to identify safety deficiencies in our existing transportation infrastructure to address rising injuries and fatalities among this group of road users. As the economy continues to struggle and fuel prices remain high, many cities and rural transportation agencies are seeing large increases in bicycling, walking, and transit ridership. While passenger car fatalities have shown sharp declines in the last …

An Automated Finite Element Analysis Framework For The Probabilistic Evaluation Of Composite Lamina Properties, Jonathan Phillips Weigand

Masters Theses

This thesis outlines the development of computational modeling tools used to predict the elastic properties of composite lamina from representative volume elements (RVE) using numerical methods. The homogenization approach involves the use of Gauss’s Theorem to simply the average volumetric strain integral into a surface integral containing which is defined by surface displacements and their direction. Simulations of RVEs under specific loading conditions (longitudinal tension or shear and transverse tension or shear) are then performed in the software package ABAQUS to obtain the surface displacements. It was found that obtaining quality meshes and applying periodic boundary conditions for each RVE …

Structural Health Monitoring And Damage Identification Of Bridges Using Triaxial Geophones And Time Series Analysis, Reza Vasheghani Farahani

Doctoral Dissertations

This study uses the vibration data of two full-scale bridges, subjected to controlled damage, along the I-40 west, near downtown Knoxville, TN, to evaluate the feasibility of time series-based damage identification techniques for structural health monitoring. The vibration data was acquired for the entrance ramp to James White Parkway from I-40 westbound, and the I-40 westbound bridge over 4th Avenue, before the bridges were demolished during I-40 expansion project called Smartfix40. The vibration data was recorded using an array of triaxial geophones, highly sensitive sensors to record vibrations, in healthy and damaged conditions of the bridges. The vibration data is …

In-Plane Shear Investigation On Masonry Walls, Shane Chandler Morrison

Doctoral Dissertations

Analysis has been performed on approximately 200 shear walls of various masonry types, reinforcement, and grouting scenarios to determine the trends of various wall parameters to strength. The database is assembled from that belonging to researchers over the last 30 years.

Strut-and-tie methods from current concrete codes are employed and new methods proposed to calculate the in-plane shear strength of masonry walls. In addition, a simplified method based upon strut-and-tie methodology is presented to calculate the masonry contribution to the in-plane strength of these walls, with contributions from axial load and horizontal reinforcement based upon past data and efficiency of …

Driver Behavior At Railway-Highway Grade Crossings With Passive Traffic Control: A Driving Simulator Study, Bryan Andre Bartnik

Masters Theses

Research to evaluate driver behavior at railway-highway grade crossings with passive traffic control attempts to find an answer to a much debated subject. This study examines the difference in driver behavior and safety at several different types of passive traffic control at grade crossings utilizing a driving simulator. This project utilized the University of Tennessee’s high fidelity driving simulator to perform a study on passive highway-railway grade crossings. Although the crash rates at grade crossings have decreased in recent years, there is still more work to be done. Safety improvements can be made to both passive and active grade crossings. …

Strength And Deformation Of “Tunable” Clay-Polymer Composites, Matthew David Bishop

Masters Theses

There are many different types of clay that exist throughout the world, and many are characterized by undesirable engineering properties. Soil improvement techniques are often implemented on these soils such as solidification, reinforcement, etc. However, these solutions are a “static” approach, as the soil’s properties cannot be modified over time. The development of the specific clay-polymer composites used in this study was motivated by the idea of creating a geomaterial that could be modified over time by adjusting its fabric, namely in the form of controlling interparticle and interlayer spacings. Therefore, the composites that are used in this study are …

Rule High School Athletic Field Renovation, Nathan W. Foust

Chancellor’s Honors Program Projects

No abstract provided.