Repair of Impact-Damaged Prestressed Concrete Bridge Girders Using Carbon Fiber Reinforced Polymer (CFRP) Materials

impact damage;flexure modeling;shear modeling;CFRP repair;prestressed concrete;bridge girder

Miller, Anthony David ; Dr. Emmett Sumner, Committee Member,Dr. Sami Rizkalla, Committee Chair,Dr. James Nau, Committee Member,Miller, Anthony David ; Dr. Emmett Sumner ; Committee Member ; Dr. Sami Rizkalla ; Committee Chair ; Dr. James Nau ; Committee Member

University:North Carolina State University

关键词: impact damage;    flexure modeling;    shear modeling;    CFRP repair;    prestressed concrete;    bridge girder;   

Others  :  https://repository.lib.ncsu.edu/bitstream/handle/1840.16/752/etd.pdf?sequence=1&isAllowed=y

美国|英语

来源: null

【 摘 要 】

Over-height vehicles impacting prestressed concrete (PS) and reinforced concrete (RC) bridge girders is a frequent problem experienced by the majority of transportation departments all over the world.The most common practice used to restore a damaged bridge is to cut out the damaged girder and replace it with a new one.More recently, alternative methods have been examined to help decrease the costs of replacing damaged girders and minimizing closure time.The research reported in this thesis considered three scenarios to examine the effectiveness of using Carbon Fiber Reinforced Polymers (CFRP) to restore impact-damaged PS girders to their original capacity.The first scenario investigated the effectiveness of CFRP sheets to repair a 54 ft (16.4 m) long girder with one ruptured prestressing strand caused by an over-height vehicle impact.The second scenario investigated the effectiveness of CFRP sheets to repair two 54 ft (16.4 m) long girders with various numbers of prestressing strands ruptured artificially at midspan.The final scenario examined the effectiveness of CFRP sheets to repair a shear-critical specimen with four prestressing strands artificially ruptured near the support.The design of all CFRP repair systems was conducted using a cracked section analysis and/or guidelines for shear capacity of prestressed members.The predictions according to the two approaches compared well with the measure values. The designs were compared to current codes and a recently developed debonding model.All of the repaired girders were able to reach and surpass their respective undamaged capacities.All of the flexural tests failed due to crushing of concrete and exhibited ductility even higher than the predicted value for the undamaged specimens.