Traffic function damage risk assessment of high-speed railway simply-supported bridges considering the total probability information expression of near-fault pulse-like earthquakes

As a critical lifeline project in high seismic intensity regions, the high-speed railway (HSR) system unavoidably involves numerous bridges located near active faults, making them highly susceptible to the threat of near-fault pulse-like (NFPL) earthquakes. This study proposes a method for assessing the traffic function damage risk of high-speed railway simply supported beam bridges (HSRSSBs), considering the total probability information of NFPL earthquakes. Focused on the post-earthquake traffic function of bridges, the method defines a comprehensive evaluation system for the function damage of HSRSSBs. Utilizing a probability model for NFPL earthquakes, an analysis function for the function vulnerability of railway bridges is proposed, considering the probabilities of earthquake occurrence, pulse period, and pulse direction. The effects of different NFPL earthquake parameters on the function damage probability of HSRSSB are analyzed. Finally, combined with the probabilistic seismic hazard analysis (PSHA) method, the study investigates the function damage risk of HSRSSBs under various site conditions and seismic risk levels. This method comprehensively considers the probability distribution of NFPL earthquakes resulting from the spatial characteristics of bridges and fault, providing valuable insights for the seismic damage risk assessment of HSR bridges in active fault regions.