Seismic loads pose a potential threat to the high-speed railway bridges in China, which have been rapidly developing in recent years, especially for those subjected to the near-fault earthquakes. The previous researches on high-speed railway bridges usually concern the far-field earthquake, and the damage of high-speed railway bridge–track system subjected to the near-fault earthquake has not been well studied. In this article, a seven-span high-speed railway simply supported bridge–track system is selected to explore the seismic damage features under the excitation of near-fault earthquake which possesses characteristics of obvious velocity pulse and high-frequency vibration. First, a detailed finite element model of the selected bridge–track system is established and calibrated by the experimental data and design code. Then the low-frequency pulse-type portion and the high-frequency background portion are separated from the selected eight original near-fault records, and a series of nonlinear dynamic analysis is conducted. The results show that the background portion leads to more serious damage of the bridge–track system than the pulse-type portion. Due to the high stiffness of high-speed railway bridge–track system, the background portion with high-frequency vibration characteristic produces the main part of seismic response of system. As for the damage part of system, the weakest component of the bridge–track system is the sliding layer, followed by the shear alveolar.

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China Railway Track System II (CRTS II) slab ballastless track structure is one of commonly adopted track systems on the high-speed railway bridge, which has been found seismically vulnerable under strong earthquakes. To investigate the earthquake-induced damage mechanism of the CRTS II slab ballastless track structure, a nonlinear numerical model of typical 7-span simply supported bridge–track system was established by the finite element software OpenSees and well calibrated by the test data and relative literatures. The nonlinear time history analysis was employed to calculate seismic responses of bridge and track parts under a suite of 10 seismic records. Results demonstrate that the sliding layer in the track structure is the most damage-prone component, especially at the bridge-subgrade transition section, and the shear alveolar may also sustain earthquake-induced fail. By analyzing the seismic damage mechanism of the track structure, this paper reveals that the nonuniform displacement responses of the girders and friction plate at the bridge-subgrade transition section are main factors that result in the extensive damage of the sliding layer and failure of the shear alveolar. However, the damage of these two components are beneficial to reduce the seismic responses of other components in the track structure and protect them from being damaged. From the perspective of engineering safety, the sliding layer and shear alveolar should be rigorously designed because the residual displacement of the sliding layer increases along with the maximum displacement and the failure of the shear alveolar may make the whole track structure failed.