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 …

Fema Region Iii Coastal Flood Study - Hampton Roads Adaptation Forum, Robin Danforth

March 28, 2014: Addressing Current and Future Vulnerability through Floodplain Management

No abstract provided.

Static, Vibration Analysis And Sensitivity Analysis Of Stepped Beams Using Singularity Functions, Peng Cheng, Carla Davila, Gene Hou

Mechanical & Aerospace Engineering Faculty Publications

A systematic approach is presented in this paper to derive the analytical deflection function of a stepped beam using singularity functions. The discontinuities considered in this development are associated with the jumps in the flexural rigidity and the applied loads. This approach is applied to static and vibration analyses of stepped beams. The same approach is later extended to perform sensitivity analysis of stepped beams. This is done by directly differentiating the analytical deflection function with respect to any beam-related design variable. The particular design variable considered here is the location of discontinuity in flexural rigidity. Example problems are presented …

Lessons In On-Campus And Distance Learning Delivery Of An Introductory Naval Architecture Course, Jennifer G. Michaeli

Engineering Technology Faculty Publications

This paper describes the author’s experiences in multi-mode (face-to-face and online) delivery of an introductory-level course on the topic of Naval Architecture geared towards anaudience of engineering and engineering technology undergraduate students with no previousmaritime background. The goal of this course is to expose talented undergraduate engineering students to the marine industry and to prepare those interested in pursing a career in this field with an introductory understanding of the complex nature of designing and building ships and other marine vessels. This course was offered in Spring 2013 and Fall 2013 to a group of engineering and engineering technology students. …

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 …

Generic Incident Model For Investigating Traffic Incident Impacts On Evacuation Times In Large-Scale Emergencies, Andrew J. Collins, Peter Foytik, Erika Frydenlund, R. Michael Robinson, Craig A. Jordan

VMASC Publications

Traffic incidents cause a ripple effect of reduced travel speeds, lane changes, and the pursuit of alternative routes that results in gridlock on the immediately affected and surrounding roadways. The disruptions caused by the secondary effects significantly degrade travel time reliability, which is of great concern to the emergency planners who manage evacuations. Outcomes forecast by a generic incident model embedded in a microscopic evacuation simulation, the Real-Time Evacuation Planning Model (RtePM), were examined to quantify the change in time required for an emergency evacuation that results from traffic incidents. The incident model considered vehicle miles traveled on each individual …

Behavior Of I-Section Gfrp Beam Including Retrofitting For Damage Effects, Mamadou Konate, Zia Razzaq

Civil & Environmental Engineering Faculty Publications

This paper presents the outcome of a study of an I-section Glass Fiber Reinforced Polymer (GFRP) beam including retrofitting for damage effects. A total of three beam tests were conducted in the following sequence: GFRP beam with no retrofitting and a single mid-span web brace; the partially damaged (cracked) beam with GFRP plates used for retrofitting; and the retrofitted beam re-tested with the lateral brace at the top flange level. Both cracking and lateral-torsional buckling behavior is studied and experimental load-deflection relationships recorded. Using the mechanical properties of GFRP based on the experimental data, theoretical predictions are made for the …