Carbon-Fiber-Reinforced Polymer Seismic Retrofit of RC Bridge Bent: Design and In Situ Validation

Abstract

Analysis and design procedures are presented for a carbon-fiber-reinforced polymer (CFRP) composite seismic retrofit of a reinforced concrete (RC) three-column bridge bent. The CFRP jacket was designed using performance-based criteria to provide a target displacement ductility based on seismic retrofit measures for the columns, bent cap, and bent cap-column joints. In situ quasi-static cyclic tests of a bent in the as-built condition and a bent retrofitted with the CFRP jacket were carried out in 1998. The seismic retrofit was successful, and the bridge bent retrofitted with CFRP composites reached a displacement ductility level in excess of the target ductility and double the hysteretic energy dissipation of the as-built bent. A description of the CFRP composite layout and validation of the design assumptions from the experimental results is presented. Recommendations for improvement of the original CFRP composite seismic retrofit design are offered based on the lessons learned from the in situ tests.