Seismic fragility assessment of bridge piers incorporating high-strength steel reinforcement and concrete under near-fault ground motions

Design codes in the United States and Canada limit the use of high-strength steel (HSS) and high-strength concrete (HSC) to bridge components that are expected to remain elastic during a seismic event. Although HSS and HSC have higher tensile and compressive strengths, respectively, their lower inelastic strain capacities impose for such restrictions. To assess the seismic performance of HSS and HSC, the pier of an existing bridge is redesigned using concrete compressive strength of 50 and 80 MPa, and reinforcement yield strength of 420, 690, and 830 MPa. Static pushover and nonlinear dynamic time-history analyses were performed to generate force-deformation and seismic fragility curves. Bridge piers incorporating HSS and HSC attained the maximum load capacity yet were the least ductile. They were less seismically vulnerable than those incorporating conventional materials at minimal and repairable damage states, but not at extensive and probable replacement damage states.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author