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The near-fault ground motion records show a noticeable velocity pulse effect, which poses a significant seismic threat to the high-speed railway track–bridge system. This study conducts the seismic response analysis of the track–bridge system under near-fault ground motions with forward directivity and fling-step effects. It quantifies the degree of damage of each track–bridge system’s key component using the component's stiffness degradation coefficient. In addition, this research investigates the influence of velocity pulse effects from near-fault ground motions on earthquake-induced residual geometric irregularities and earthquake-induced dynamic irregularities. It explores the post-earthquake running performance of high-speed trains based on the input of earthquake-induced irregularities, providing a theoretical basis for the seismic design method of the track–bridge system based on running safety. The research results indicated that the stiffness degradation of the track–bridge system under near-fault pulse-type ground motions is more severe compared to near-fault non-pulse ground motions and mid-far-field ground motions. The amplitudes of earthquake-induced residual geometric irregularity and earthquake-induced dynamic irregularity of rails under near-fault pulse-type ground motions are much greater than those under near-fault non-pulse and mid-far-field ground motions. The earthquake-induced alignment irregularity significantly impacts high-speed trains' derailment coefficient and transverse acceleration. Consequently, failing to account for the velocity pulse effect of near-fault ground motions can lead to an overestimation of the post-earthquake running capacity of the track–bridge system. Seismic design considerations for high-speed railway bridges must prioritize the influence of velocity pulse-type ground motions.

High-speed railway bridges are inevitably damaged under external loads during operation, which may lead to abnormal vibration of trains, and even threaten running safety. Aiming at the practical problem of high-speed railway longitudinal ballastless track structure damage, based on the train-track-bridge interaction theory, a three-dimensional coupled vibration model of a train-track-bridge was developed using the finite element method. The dynamic response calculation program (TTBCS) was developed using the Newmark-β numerical calculation method. The model and program were used to calculate and analyze the influence of damage to the main components of high-speed railway ballastless track-bridge structure on the dynamic response of the system, including fastener failure, interlayer component damage, and bearing vertical stiffness degradation. The results show that the fastener failure significantly influences the vertical interaction of the wheel-track. The number of fastener failures should not exceed one pair otherwise there is a risk of derailment. When the CA (cement and emulsified asphalt) mortar layer and the slide layer void length exceeds the critical value, the dynamic irregularity of the track-bridge system significantly increases the vertical vibration of the wheel-track system. The critical value of void should be given more attention to in the operation of high-speed railways. The vertical dynamic performance of the train is not sensitive to the change in vertical support stiffness within a certain range of stiffness values but within a certain operation speed range, adjusting the bearing stiffness can play a certain vibration isolation effect.