Engineering Commons^™

Effective Cfrp Retrofitting Schemes For Prestressed Concrete Beams, Herish Abdullah Hussein

Civil & Environmental Engineering Theses & Dissertations

This thesis presents a detailed theoretical study of a number of retrofitting schemes for prestressed concrete beams using carbon fiber reinforced polymer (CFRP) sheets to increase flexural strength and ductility. A simply-supported beam subjected to a gradually increasing uniformly distributed load is adopted for the study with a variety of CFRP retrofiring schemes. Three different types of beam cross sections are included for quantifying the influence of CFRP retrofitting when used in high compression regions in addition to CFRP use in high tension areas. To achieve this goal, nonlinear moment curvature relations are developed and coupled with a finite-difference solution …

Feasibility Of Mainstream Nitrite Oxidizing Bacteria Out-Selection And Anammox Polishing For Enhanced Nitrogen Removal, Pusker Raj Regmi

Civil & Environmental Engineering Theses & Dissertations

Short-cut nitrogen removal avoids nitrite oxidation to nitrate by nitrite oxidizing bacteria (NOB) and allows a) reduction of formed nitrite to nitrogen gas via heterotrophic denitrification and/or b) oxidation of remaining ammonia with formed nitrite to nitrogen gas via anaerobic ammonia oxidation (anammox). The precondition for achieving shortcut nitrogen removal is suppression of NOB, which is favored by warm and high ammonia strength conditions found in internally generated ammonia-rich waste streams through anaerobic digestion of waste solids referred to as sidestreams or reject water. The discovery of anammox bacteria in the mid-1990s, which are capable of transforming NH₄+ …

Stormwater Infrastructure Optimization On Conjunctive Improvements, Mohammad Hussin Shar

Civil & Environmental Engineering Theses & Dissertations

The studied drainage system is located in the downtown of the City of Newport News, in a basin known as Anderson Park. The drainage system collects and conveys rainfall runoffs to the system outfall located at the shoreline of the Hampton Roads body of water, which is located south of the study area. The aim of this study is to analyze the area's drainage system, determine maximum capacities, identify system deficiencies and generate the most possible, practical and economical solution for fixing the system deficiencies.

After collecting all of required data, the drainage system was modeled and calibrated using the …

Flash Hydrolysis Of Microalgae Biomass For Biofuels Intermediates Production, Protein Extraction, And Nutrients Recycle, Jose Luis Garcia Moscoso

Civil & Environmental Engineering Theses & Dissertations

Microalgae have shown much higher growth rates and productivity when compared to conventional agricultural crops, aquatic plants and tree species, requiring much less land area than other biodiesel feedstock. To harness that potential the hydrothermal liquefaction of algae biomass was studied and a new process called "Flash Hydrolysis" was developed to use water under subcritical conditions, this process capitalizes on the difference in reaction kinetics of algae polymeric components and fractionates proteins in liquid phase in seconds of residence time.

The main objectives for this study are: Analyze the effect of temperature in FH process to maximize the extraction of …