چکیده
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This paper investigates the seismic performance of Reinforced Concrete (RC) bridges located in the coastal environment of Bandar Abbas, Iran. To this aim, first probabilistic seismic hazard analysis results of the region covering a radius of 150 km, keeping Bandar Abbas as the centre, are presented. To determine the dominant earthquake scenario characterized by magnitude and source-to-site distance, disaggregation of Peak Ground Acceleration (PGA) hazard corresponding to mean return periods of 475 and 2475 years is carried out. Results of disaggregation analysis are employed to select a ground motion set for nonlinear dynamic time history analysis of the considered bridge. In the next step, the effects of chloride-induced corrosion on the bridge columns, including the degradation of steel bar, cover concrete and core concrete properties, are considered at different time steps in bridge service life. Finally, seismic fragility curves of the corroded bridge at selected time steps are developed based on the multiple stripe analysis results and maximum likelihood approach. Based on the analyses results, to ensure the appropriate seismic performance of RC bridge in its service life, it is proposed that the design PGA should be increased approximately by 37%
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