Digital Commons Network^™

Stability Analysis Of Single And Double Steel Girders During Construction, Sean Justin Coffelt

Masters Theses

Built-up steel I-girders are very commonly used in bridge construction. Their spans are typically very long, and they are susceptible to lateral torsional buckling if not enough lateral support is provided. This thesis includes guidelines for preventing lateral torsional buckling of steel I-girders under dead and wind load, accompanied with finite element analysis of double girder systems. The first portion includes capacity envelopes for single girders with single and double symmetric cross sections under various loading conditions and boundary conditions for double and single symmetric cross sections with double girders subjected to dead loads only. The second portion is dedicated …

Streamflow Reconstructions In The Tennessee Valley Using Tree-Ring Chronologies, Ross William Ogle

Masters Theses

Tennessee Valley surface water is important to economic and population growth in the southeastern United States. By expanding streamflow records, water planners and managers can make decisions based on hydrologic events not appearing in current instrumental records. In the following research, monthly flow data from six USGS streamflow gages on the Clinch, Emory, Holston, and Nolichucky Rivers is used to create seasonal and annual streamflow seasons. Approximately 70 tree-ring chronologies across the Southeast U.S. are prescreened by length and correlation analysis against 38 streamflow seasons revealing that the May-June-July (MJJ) streamflow period displays the best tree-ring climate signal. The screened …

Stormwater Best Management Practices: Improvement And Evaluation, Brent Steven Pilon

Masters Theses

Each of the studies conducted herein is related to best management practices for stormwater pollutant removal. This thesis is divided into two chapters. Chapter One details the development and functionality of a novel stormwater detention pond outlet, the solid state skimmer. The device is a perforated riser having no moving parts that is capable of draining detention ponds primarily from the topmost orifices. We found that such a device is capable of reducing effluent turbidity and sediment concentrations compared to a traditional riser outlet. Chapter Two describes a water quality monitoring study performed to show that a pervious concrete detention …

Seismic Analysis Of Integral Abutment Bridges Considering Soil Structure Interaction, Reza Vasheghani Farahani

Masters Theses

Integral abutment bridges are jointless bridges in which the deck is continuous and connected monolithically with the abutment walls supported typically by a single row of piles. This thesis focuses on the effects of two major parameters on the seismic behavior of an integral abutment bridge in Tennessee by considering soil-structure interaction around the piles and in back of the abutments: (1) clay stiffness (medium vs. hard) around the piles, and (2) level of sand compaction (loose vs. dense) of the abutment wall backfilling. Modal and nonlinear time history analyses are performed on a three dimensional detailed bridge model using …

Wind River Range Snowpack Reconstruction Using Dendochronology And Sea Surface Temperatures, Sallyrose Anderson

Masters Theses

Multiple reconstructions of April 1st snow water equivalent (SWE) are generated for the Wind River Range (WRR), located in west-central Wyoming, to determine the most accurate predictors. Predictors included climate signal data (Southern Oscillation Index), traditional predictors (tree-ring chronologies), and non-spatially biased Pacific Ocean sea surface temperatures (SSTs). Incorporation of Pacific Ocean SSTs as a whole provides a more comprehensive representation of oceanic-atmospheric variability. Rotated principal component analysis (PCA) was used to regionalize April 1st snowpack data (1961 – 1999) from snow telemetry stations (SNOTEL stations). Tree-ring chronologies that were stable across the period of overlapping records (1961 – 1999) …

Evaluation Of Moisture Damage In Warm Mix Asphalt Containing Recycled Asphalt Pavement, Emily D. Shrum

Masters Theses

Warm mix asphalt (WMA) has been used worldwide for many years, primarily in Europe. The National Asphalt Pavement Association first brought WMA to the United States in 2002. By using warm mix technology, the temperature of an asphalt mixture during production, transportation, and compaction decreases dramatically. Several concerns about WMA arise due to the reduced mixing temperature. One of the primary concerns in asphalt pavement is the moisture damage. The lower mixing temperature may not be high enough to vaporize all the moisture absorbed in the aggregate, and part of the moisture may be entrapped in the pavements during compaction. …

The Characteristics Of Underground Utility Repairs Made In Asphaltic Roadways – Comparing The Use Of Grade D Aggregate As A Viable Backfill Option, Susan Gail Deland

Masters Theses

Abstract

Given that most utilities are located beneath public right of ways, it is difficult to perform repairs to the utility without significantly disturbing the existing roadway. Currently there are several standard orders of procedure that deal with small-scale repairs on asphaltic surfaces. This study investigates the use of Grade D Aggregate as a backfill during a utility repair versus the condition of the repair. Five East Tennessee utilities provided a total of 60 utility repair locations over three years of age; 30 of which incorporated Grade D Aggregate and 30 incorporated #57 Stone.

The Tennessee Department of Transportation specifies …

Streamflow Reconstructions Of Southern Appalachian (North Carolina) Headwater Gages Using Tree Rings, James Tate Geren

Masters Theses

Tree rings have been used as a proxy in reconstructing streamflow in the western U.S. for many years, but few reconstructions have been attempted in the eastern United States. Clear limitations exist for streamflow reconstructions in the eastern U.S. compared to the western U.S., but value can be established as demonstrated in this research. The primary goal of this research was to reconstruct streamflow using data from five headwater gages in the Appalachian Mountains of North Carolina. These gages are located on the Valley River, the Oconaluftee River, the Nantahala River, the Little Tennessee River, and the Watauga River. Tree-ring …

Increasing The Structural Engineer’S Influence Over Sustainability By Using Integrated Design Teams, Mary Elizabeth French

Masters Theses

Sustainability is quickly becoming a “buzz word” in today’s environmentally conscious world from political leaders to building professionals to design experts to consumers as they rethink their impact on current healthy, efficient indoor/outdoor environments as well as long term benefits to future generations.

This paper seeks to investigate ways to increase the structural engineer’s influence over the sustainability of the building industry by using integrated design teams. It explores current practices within the building industry, in particular the housing industry and the ways in which the integrated design team differs from most current practices. It strives to promote the positive …

Dynamic Characteristics Of An Frp Deck Bridge, Jing Song

Masters Theses

Fiber reinforced polymer (FRP) deck has some significant advantages compared to concrete deck in use of bridges, such as light self-weight, high stiffness and strength, good durability and easy to install. FRP deck has already been used in some bridge rehabilitation and short span bridges. But for widely used in bridges, FRP deck bridges still need further research. Currently many research efforts focus on the filed tests of FRP deck bridges. Compared to field tests, Finite element analysis also has great advantages, such as low cost and convenient to conduct. Therefore, in this thesis finite element analysis is conducted by …

Behavior Of Precast Bridge Deck Joints With Small Bend Diameter U-Bars, Cheryl Elizabeth Chapman

Masters Theses

The Interstate Highway System plays a vital role in our economic development by providing a continuous corridor for transporting goods and services. Currently, there is a need for repair and expansion of the existing highways, which include all bridges along its path. Because of the high demand for the highway system, repair and expansion must occur rapidly and efficiently. In recent years, precast bridge deck systems have become an efficient way to reduce construction time during repair.

This thesis presents the experimental research of the behavior of the U-Bar joint detail used in precast bridge deck systems. This detail consists …

An Investigation For The Need Of Secondary Treatment Of Residential Wastewater When Applied With A Subsurface Drip Irrigation System, Boone S. Hillenbrand

Masters Theses

The objective of this study was to investigate the need for domestic wastewater to receive secondary treatment when being applied to the soil by subsurface drip irrigation (SDI). SDI uniformly distributes wastewater into the soil, which optimizes the soil’s chemical, physical, and biological capacity to remove waste constituents. Because of these advantages, many regulatory jurisdictions are allowing SDI at sites that previously were prohibited from using conventional trench-based soil application systems because of shallow soil restrictions. However, most of these regulatory agencies also require that the wastewater receives secondary treatment (dissolved organic carbon reduction) before the SDI system. At issue …

Georeferenced Riverine Habitat Mapping In The Big South Fork National River And Recreation Area, James Bryan Mcconkey

Masters Theses

Abstract

This project describes the development of a river habitat map of the Big South Fork National River and Recreation Area (BISO NRRA) using GPS-based video mapping and image georeferencing techniques. The Big South Fork of the Cumberland River and major tributaries have been floated and mapped with GPS, sonar, and georeferenced under and above water video cameras. Video footage is interpreted for physical bedforms and compiled in an ArcGIS attribute table that can be queried for species specific habitat location.

Underwater video mapping system (UVMS) bedform data includes river characteristic (pool, riffle, run), substrate (bedrock, fines/sand, gravel, cobble, and …