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Using Multivariate Analysis Of Geochemical Data To Better Define Hydrologic Interfaces In Surface Water - Groundwater Systems, Candice Ann Owen

Masters Theses

Groundwater-surface water interactions have been shown to be important to flow generation and stream chemistry in upland catchment environments. These areas, however, are often difficult to access making the implementation of standard hydrological surface and subsurface monitoring equipment and characterization procedures impractical, arduous and in many cases impossible due to the nature of the terrain and also regulatory guidelines for protected areas. By collecting surface water samples at distinct water contribution sites to a headwater stream, areas of groundwater influence were inferred and a hydrochemical conceptual model of a small basin was created.

The objectives of this research were to …

Characterizing Groundwater-Surface Water Interactions In Great Smoky Mountains National Park Using Hydrologic, Geochemical & Isotopic Data, Amanda Marie Mckenna

Masters Theses

Groundwater-surface water interactions can substantially influence the quality of surficial water bodies and are thus important when investigating ecological health of and climate change impacts on an area. However, data collection can be hindered when the location is remote and/or legally protected. This paper presents a methodology to implement minimallyinvasive field techniques at a remote and protected location that allows preliminary identification of the relationship between groundwater and surface water. Great Smoky Mountains National Park was selected as the study area as it is subjected to some of the highest rates of acid deposition in the country. Ecological damage is …

Blast Resistant Design Of Steel Structures, Sarah Beth Janney

Masters Theses

The purpose of this study was to examine the load experienced by a steel blast cubicle from a surface blast test. An important objective was to determine the blast load experienced at different standoff distances and the blast resistance capability of the blast cubicle. Three cubicles with standoff distances of 20, 25, and 30ft respectively were simultaneously subjected to a 50lb TNT explosive. The manual Structures to Resist the Effects of Accidental Explosions, Army TM 5-1300 conservatively predicted the blast pressure loadings obtained from the pressure transducers mounted on the cubicles. Data collected from accelerometers was compared to results from …

Health Monitoring Of Concrete Bridges Utilizing Sensor Technology, Ammar Zalt

Masters Theses

Structural health monitoring using sensor technology is a promising way to provide excellent means for protecting important structures such as bridges, dams, and nuclear reactors. These sensors provide real-time information about structural conditions, They work together as a nervous system to provide timely information for emergency and risk mitigation. The information obtained from these sensors can later be analyzed and compared to the design data so that the problem can be detected and fixed before it develops into a serious and costly hazard.

Throughout the course of this thesis the feasibility and performance of two types of sensors will be …

Physiological Stress In Native Brook Trout (Salvelinus Fontinalis) During Episodic Acidification Of Streams In The Great Smoky Mountains National Park, Keil Jason Neff

Masters Theses

Episodes of stream acidification are suspected to be the primary cause of the extirpation of native southern brook trout (Salvelinus fontinalis) from six headwater streams in the Great Smoky Mountains National Park (GRSM). During periods of increased flow from storm events, stream pH can drop below 5.0 (minimum of 4.0) for 2-days or longer. To provide evidence that native brook trout are impacted by stream acidification, in situ bioassay experiments were conducted. Changes in stream water chemistry and brook trout physiology were determined during a 36-hour acidic episode at three remote headwater stream sites in the Middle Prong of the …

Evaluation, Comparison, And Design Of Two Experimental Bridges In Tennessee, Kyle Parker Scoble

Masters Theses

This thesis describes the design and evaluates the adequacy of the moment connection of an experimental two-span highway bridge designed by the Tennessee Department of Transportation. The Massman Drive bridge is an experimental design that unifies the construction economy of simple span bridges and the structural economy of continuous span bridges. The experimental connection, consisting of cover plates and kicker wedge plates, is used to connect the two adjoining girders over the center pier. As a result, the bridge is designed to function as a continuous bridge during the deck pour and behave compositely with the reinforced concrete deck under …

“Parametric Study Of The Effects Of Water To Cementitious Materials Ratio And Cementitious Materials Content On The Durability Properties Of High Performance Concrete, Andrew T. Tinsley

Masters Theses

This study takes a detailed look at the factors that affect the durability of concrete and how they can be applied to the development of a useful performance specification and help to extend the life of bridge decks and other concrete structures exposed to the elements of nature. A series of fifteen mixes (with varying cement contents and water/cement ratios) were performed in order to determine exactly which of these factors have a significant effect on the durability of a concrete mix. Controlling the water/cement ratio is necessary in order to control strength and permeability. Cement content was found to …

Data Fusion Technique For Measuring Intersection Delay Using Gps-Enabled Probe Vehicles, Byung-Hee Han

Masters Theses

Intersection control delay is considered a primary measure for determining the level of service at signalized intersections. This thesis develops a technique estimating intersection delay using GPS data from GPS-enabled vehicles. First, this study analyzes existing methods that estimate control delays using GPS data and proposes an improved technique in response to the weakness of those methods. The proposed method estimates the control delay well with better accuracy covering the weaknesses. However, the control delay from the GPS data has a sample size problem for determining the level of service at signalized intersections. Therefore, this thesis proposes a data fusion …

Development Of Knowledge Base Of Concrete Bridge Maintenance System, Bahre Karam

Masters Theses

Bridges are the key elements of any transportation system of a country. Bridges are expensive structures and therefore, it's essential to maintain and repair them on regular basis. Almost one third of the bridges in United States are reported to be in some what deteriorated conditions. This Research presents the development of knowledge base for decision support system for concrete bridges.

During this research various concrete bridge problems are investigated including COlTosion, delamination, cracks, spalling and scour etc. The inspection tools and techniques are addressed in order to identify these problems both for above and below water surface. The various …

Experimental Investigation Of Reinforced Concrete Beams With Lapped Reinforcement, Mary Elizabeth Griffey

Masters Theses

One of the great contributions made by President Dwight D. Eisenhower was his influence in the implementation of the National Interstate and Defense Highways Act of 1956. The National Highway System serves an important role in American citizen's ground transportation. Now more than a half of a century in age, there is a high priority to repair existing infrastructure as well as the need for expansion. Repair and expansion must be achieved efficiently by reducing construction time and improving the capacity and durability of the structure. Precast, prestressed decked bulb tees (DBTs) serve as an excellent solution to ensure quality …

Design Considerations For Reinforced Concrete Masonry Walls Regarding Moment Magnification, Jarred Wade Cowart

Masters Theses

Currently, regardless of the height of a reinforced masonry wall, engineers are required to consider moment magnification when using strength design provisions. An attempt at finding reasonable h/r limits for consideration of moment magnification is explored. Moment-curvature diagrams were developed using a spreadsheet to define the behavior of 8 inch and 12 inch concrete masonry walls. A series of models were created with axial load, out-of-plane load, height, reinforcing, and wall width as variables. The models were loaded out-of-plane in a finite element program until failure. The results were organized to produce the moment magnification of each wall. Results were …

Determination Of Air Flotation Parameters To Perform Solid Liquid Separation Treatment In An Activated Sludge Treating Grease Waste By Promoting Filamentous Bacteria, Juan Guillermo Cartajena Torrealba

Masters Theses

The focus of this investigation was the determination of air flotation parameters to perform solid liquid separation treatment in an activated sludge treating grease waste by promoting filamentous bacteria. The treatment was intended to achieve a pretreatment level, previous to the application of the typical activated sludge process.

Generally solid liquid separation in activated sludge is performed by gravitational settling, but it is been demonstrated that the presence of an overgrowth population of filamentous microorganism in activated sludges hinder the settling properties of it. For this reason, gravitational settling may result in an inefficient treatment. Therefore, an alternative treatment has …

Commerical Vehicle Enforcement Using License Plate Recognition Technology, Stephanie R. Hargrove

Masters Theses

Speed limits for large trucks have been reduced at many locales for air quality and safety reasons. To realize an improvement in air quality and safety, however, diligent enforcement and fitting punishment have to be implemented. This may put a strain on already tight resources and manpower for state and local agencies. To this end, this paper presents a license plate recognition (LPR) technology based heavy vehicle speed enforcement system that requires relatively minimal initial investment and no increase in enforcement personnel, cruisers, or pursue/pull-over activities. The efficiency of the system is achieved by catching speeding trucks in the act …

Performance Evaluation Of Existing Analytical Methods To Compute The Shear Contribution Provided By Externally Bonded Frp Sheets In Concrete Structures, Rocio Patricia Tumialan

Masters Theses

"External application of FRP composites has been adopted for strengthening and/or repair of concrete structures in many applications during the last two decades. However, the research into shear strengthening using FRP composites has not been widely conducted as compared to flexural strengthening and axial load capacity increase, and the results obtained thus far are scarce and sometimes controversial. This study presents a review of analytical studies and design guidelines on shear strengthening of concrete structures with externally-bonded FRP laminates, and their assessment with experimental data collected from the literature. The strengths and weaknesses of each model and design guidelines/codes/specifications are …

Static Evaluation Of The Out-Of-Plane Behavior Of Urm Infill Walls Utilizing Modern Blast Retrofit Systems, Trevor D. Hrynyk

Masters Theses

"Previous investigations have shown that the use of modern retrofit systems can significantly improve the behavior of URM infill walls subjected to variable out-of-plane loads. It has also been shown that the use of externally bonded retrofit systems can greatly reduce the amount of fragmentation and debris scatter that is found to occur in URM walls subjected to high intensity blast loads...The main objective of this study is to investigate, through static testing, the use of modern materials for the purpose of improving the behavior of URM walls subjected to blast loads. This study implemented externally bonded FRP grids and …

Vapor Phase Uptake Of Volatile Organic Contaminants By Hybrid Poplar Trees, Sally Rebecca Breite

Masters Theses

"Phytoremediation, the use of plants to immobilize, degrade or remove contaminants from the environment, shows great promise as a remediation technique for many contaminated sites. Phytovolatilization in particular is of great interest for sites contaminated with chlorinated solvents and other volatile organic compounds (VOCs), many of which are recalcitrant to biodegradation. Hybrid poplar trees have been shown to uptake, translocate and volatilize numerous aqueous-phase VOCs, however vapor phase uptake of such compounds has only recently been observed and for only one contaminant, tetrachloroethylene (PCE). One semi-volatile and five volatile compounds were dosed to poplar trees in aqueous and vapor phase …

The Importance And Influence Of Groundwater Fluctuations In Phytoremediation, Jeff A. Weishaar

Masters Theses

"The primary purpose of this research is to study the relationship between microbial degradation and plant uptake of volatile hydrocarbons, such as benzene, toluene, ethylbenzene and xylene. While these compounds are known to biodegrade and are capable of transport into plant tissue, any relationship between the two removal mechanisms remains largely unknown. The goal of this work is to better understand the interactions of these multiple biological processes within a phtytoremediation effort"--Introduction, page 3.

Analysis Of Soil Erosion Based On Soil Properties, Preetha Veeraraghavan

Masters Theses

"The objectives of this research were to identify the major soil parameter(s) that affect the erosion rate of soil and to estimate the erosion rate based on those soil parameters. Both prepared samples and natural samples were used in this research. The soil properties analyzed were the water content, unit weight, Atterberg limits, and soil cohesion. The erosion rate was determined using a rectangular flume and a linear relation between the erosion rate and shear stress was established from the flume experiment. The slope of the linear relation was a good indicator of the soil's erosion rate. The erosion rate …

Ph Effect On Adsorption Of Saxititoxin On Powdered Activated Carbon, Jie Ding

Masters Theses

"The presence of algal toxins, or cyanotoxins, in surface water has been increasingly reported. These highly hazardous toxins are potential threat to both human health and animals by contaminating drinking water sources over the world. In this study, the removal efficiency of saxitoxin from water using powered activated carbon was tested at different pH values for deionized water and natural surface water. The results of this study showed that pH has a strong impact on removal efficiency of saxitoxin using powdered activated carbon. Specifically, the removal efficiency of saxitoxin is significantly increased at higher pH from 5.7 to pH 10.7. …