Damage control analysis of components in high-speed railway bridge-track system based on combined seismic isolation design under earthquake

In order to ensure the running safety of high-speed trains, it is necessary to control the post-earthquake damage of the components in high-speed railway bridge-track system (HSRBTS). In this paper, the damage control indexes of each component in HSRBTS are determined, and the overall seismic performance objectives of HSRBTS are quantified based on the component damage control requirements. Based on the finite element analysis, the damage control of the components in HSRBTS is analyzed under the combined design of friction pendulum bearing and metal damping tenon. The analysis results show that the damage of track interlayer components can be controlled by the combined seismic isolation design, and the sensitivity of the damage response of components to ground motion characteristics can be reduced. The maximum damage overrun length (LDmax) proposed and adopted in this paper is used as the damage control index of track interlayer continuous components, which can quantify the damage degree of interlayer continuous components and realize the fine damage control of interlayer continuous components. By optimizing the parameters of the combined seismic isolation design, the damage control of CA mortar layer, fasteners and sliding layer can meet the quantified seismic performance objective proposed in this paper. The friction pendulum bearing and the metal damping tenon can play the seismic isolation performance together, which can avoid the concentrated damage of pier and bearing and realize the distribution and dissipation of seismic energy.