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Imaging Of Buried Utilities By Ultra Wideband Sensory Systems, Arun Prakash Jaganathan Oct 2008

Imaging Of Buried Utilities By Ultra Wideband Sensory Systems, Arun Prakash Jaganathan

Doctoral Dissertations

Third-party damage to the buried infrastructure like natural gas pipelines, water distribution pipelines and fiber optic cables are estimated at $10 billion annually across the US. Also, the needed investment in upgrading our water and wastewater infrastructure over the next 20 years is estimated by Environmental Protection Agency (EPA) at $400 billion, however, non-destructive condition assessment technologies capable of providing quantifiable data regarding the structural integrity of our buried assets in a cost-effective manner are lacking. Both of these areas were recently identified several U.S. federal agencies as 'critical national need'. In this research ultra wideband (UWB) time-domain radar technology …


Evaluation Of Experimental Bridges In Tennessee, David P. Chapman Aug 2008

Evaluation Of Experimental Bridges In Tennessee, David P. Chapman

Doctoral Dissertations

This dissertation presents an overview and evaluation of an effort of the Tennessee Department of Transportation (TDOT) to design multispan steel girder bridges that can be erected with minimal disruption to traffic passing under the proposed spans. TDOT has developed the Pier-Plate Moment Connection in order to facilitate the accelerated construction of steel girder bridges. This connection allows the girders of a multispan steel bridge to be erected as simple spans and then to be made continuous prior to the dead load of the deck being applied. Since 2003, the Department of Civil and Environmental Engineering at the University of …


Physical Modeling Of Railroad Ballast Using The Parallel Gradation Scaling Technique Within The Cyclical Triaxial Framework, Adam F. Sevi Jan 2008

Physical Modeling Of Railroad Ballast Using The Parallel Gradation Scaling Technique Within The Cyclical Triaxial Framework, Adam F. Sevi

Doctoral Dissertations

"Due to the difficulties involved with testing large particle granular materials such as rockfill and railroad ballast, several methods of testing scaled down model specimens have been introduced. Of these techniques, the parallel gradation model has been found to be most useful. The parallel gradation model states that a smaller grainsize distribution model granular material, of the same composition as the prototype material, can be used in triaxial testing at a scaled down grainsize, if the model materials grainsize is exactly parallel to the prototype material. Therefore, a model granular material composed of a smaller, but parallel, grainsize distribution can …


Formation And Removal Of Pesticides And Pesticide Transformation Products During Water Treatment, Evelyn F. Chamberlain Jan 2008

Formation And Removal Of Pesticides And Pesticide Transformation Products During Water Treatment, Evelyn F. Chamberlain

Doctoral Dissertations

"A comprehensive suite of over 60 pesticides (herbicides, insecticides, and fungicides) representing a variety of classes at environmentally relevant concentrations (low µg/L) were screened for reactivity under typical drinking water conditions and dosages. The most common oxidants/transformation agents in water treatment systems were examined for reactivity including free and combined chlorine, chlorine dioxide, permanganate, ozone, hydrogen peroxide, ultraviolet radiation, and high pH (alkaline hydrolysis). Due to the broad nature of the study, pesticide compounds were analyzed as multiple mixes broken into two groups based on analytical methods, those analyzed by GC/ECD and those by LC/MS. Combinations of reactive disinfectant/oxidant and …