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Export Of Carbon, Nutrients And Microbiological Indicators In Beaver Creek Watershed, Tennessee, Si Chen
Export Of Carbon, Nutrients And Microbiological Indicators In Beaver Creek Watershed, Tennessee, Si Chen
Masters Theses
Storms are the most important events impacting stream water quality at the watershed-scale. With the goal to develop effective water resource management strategies for the impaired Beaver Creek Watershed in East Tennessee, the impacts of storm events on water quality were assessed by monitoring the intra-storm dynamics of the export of carbon, nutrients, and microbiological indicators (E. coli), which are parameters critical to water quality and ecological functions of the target watershed. The dynamics of carbon export from the Beaver Creek Watershed as represented by dissolved organic carbon revealed distinct carbon transport mechanisms as a function of storm …
Stream Channel Stability And Channel Evolution In A Rapidly Urbanizing, Ridge-And-Valley Watershed, Beaver Creek, Knox County, Tennessee, Francis Bartholomew Keaney
Stream Channel Stability And Channel Evolution In A Rapidly Urbanizing, Ridge-And-Valley Watershed, Beaver Creek, Knox County, Tennessee, Francis Bartholomew Keaney
Masters Theses
In Tennessee, sedimentation is among the leading causes of stream impairment. Excessive loads of alluvium are detrimental to the ecological health and human use of these resources. Sediments in streams have many sources, but there is evidence that stream bank erosion is a major contributing factor. Development and urbanization in a stream’s watershed will have impacts on the concentration of stream sediment because the increase in the area covered by impervious surfaces, which reduces initial abstraction and retention times. This, in turn will increase the peak storm water discharge and sediment carrying capacity. If the stream channel cannot accommodate these …
Characterizing Episodic Stream Acidification Using A Concentration-Duration-Frequency Methodology In Watersheds Of The Great Smoky Mountains National Park, John Leland Mauney Iii
Characterizing Episodic Stream Acidification Using A Concentration-Duration-Frequency Methodology In Watersheds Of The Great Smoky Mountains National Park, John Leland Mauney Iii
Masters Theses
Episodic stream acidification occurs as storm events temporarily reduce acid neutralizing capacity and pH. Stream acidification is suspected to have damaging effects on the health of aquatic ecosystems and biota and is dependent on various watershed characteristics such as drainage area, elevation, slope, and surficial geology. Here, a stochastic modeling approach is applied to continuous pH data for multiple stream monitoring sites within the Great Smoky Mountains National Park in order to characterize episodic acidification responses during stormflows for different streams. The approach summarizes voluminous pH data recorded by water quality sondes at 15-minute intervals into concentration-duration-frequency relationships. Unique to …
Geotechnical Site Characterization Using Multi-Channel Analysis Of Rayleigh And Love Waves, James David Lane, Jr.
Geotechnical Site Characterization Using Multi-Channel Analysis Of Rayleigh And Love Waves, James David Lane, Jr.
Masters Theses
The Multi-Channel Analysis of Surface Waves (MASW) is a technique in which surface waves can be analyzed to determine soil shear wave velocity profiles with depth. The shear wave velocity of soil can be used to calculate the shear modulus, which is an important geotechnical engineering parameter. Site surveys were conducted and analyzed located at a location on the flood plain of the Tennessee River. The flood plain consists of a thin layer of soil above rigid (Knox Dolomite) bedrock and exhibited strong stratification. Three different aspects of MASW data acquisition and analysis are presented in the study. The first …
Structural Behavior Of A Pile Framed Tie Back Retaining Wall, Mieah Dee Turner
Structural Behavior Of A Pile Framed Tie Back Retaining Wall, Mieah Dee Turner
Masters Theses
The objective of this research study is to analyze the preliminary structural behavior of a pile framed tie back retaining wall concept created by the Tennessee Department of Transportation (TDOT). Instrumentation is used to measure the forces and moments on the steel piles, loads on the anchors, and the pressure and displacement of the retained soil over time. Data collection for steel pile analysis consisted of the comparison of strain gage readings. Stress values were calculated from the readings and reduced down to an axial and bending force along the pile. Soil pressures that built up behind the wall were …
Impact Of Larger Diameter Strands On Aashto/Pci Bulb-Tees, Jayaprakash Vadivelu
Impact Of Larger Diameter Strands On Aashto/Pci Bulb-Tees, Jayaprakash Vadivelu
Masters Theses
This thesis consists of the analytical study and the experimental investigation of larger diameter strands in AASHTO Type I girders. The main purpose of this study was to verify that the 2 inch minimum spacing recommended by ACI 318-08 and AASHTO (2008) can be used for 0.7 inch diameter strands by comparing various effects in girders using 0.7 and 0.6 inch diameter strands. Based on the parametric analysis it was concluded that by using 0.7 inch strands there was a considerable saving in the material. For example, an AASHTO BT-72 with 0.6 inch strand could be replaced with AASHTO BT-54 …
Method Of Evaluation For Stream Bed Shear Stress And Sediment Transport Capacity In Urbanizing Watershed: Implications For Stream Restoration, William Cantrell
Method Of Evaluation For Stream Bed Shear Stress And Sediment Transport Capacity In Urbanizing Watershed: Implications For Stream Restoration, William Cantrell
Masters Theses
In the field of stream restoration, use of a one-dimensional flow model with typical Manning’s n values for an open channel greatly over-predicts bed shear values. This, in turn, incorrectly predicts the size of the mobile fraction on the bed and if used in a bedload transport function over-predicts mass movement of the bed material. This study identified 12 sites for which watershed and reach characteristics were compiled, and bedload sampling was performed. This information was used to produce an empirical relationship between reach pebble count data and an effective Manning’s n value that can be used to produce accurate …
Effect Of Ambient Temperature And Humidity On Aging Of Nanocarbons, Liangcheng Yang
Effect Of Ambient Temperature And Humidity On Aging Of Nanocarbons, Liangcheng Yang
Masters Theses
We researched effect of ambient temperature and humidity on aging of nanocarbons, including carbon nanotubes and fullerenes. We studied physicochemical properties of these nanocarbons stored in ambient conditions (20oC, 35-55%RH) for 24 months, in 90% relative humidity (RH) environment for 8 months and in 37oC environment for 13 months. We measured surface area and pore volume of samples by using N2 adsorption (77K) technique and characterized surface chemistry by using X-Ray photospectroscopy and FT-IR spectroscopy. We also analyzed structural defects with Raman spectroscopy. All tests were conducted periodically.
In ambient condition, we found that nanocarbons …
Experimental Investigation Of Precast Bridge Deck Joints With U-Bar And Headed Bar Joint Details, Samuel Lewis
Experimental Investigation Of Precast Bridge Deck Joints With U-Bar And Headed Bar Joint Details, Samuel Lewis
Masters Theses
This thesis presents the experimental investigation of two joint details for use in precast bridge deck systems. U-bar and headed bar joint details were developed for use in accelerated construction applications. Both details, in practice, would consist of staggered protruding reinforcement that would allow for the anchorage of the precast deck component into the joint. Six specimens containing the joint details were constructed and tested. Three specimens were tested in flexure to simulate the forces that would be experienced in a longitudinal deck joint, and three specimens were tested in tension to simulate the forces that would be experienced in …