Study on practical calculation method of post-earthquake traffic capacity of high-speed railway bridge

High-speed railway bridges are critical lifeline infrastructure during earthquake rescue operations. To effectively evaluate the post-earthquake capacity of high-speed railway bridge, an intensity index system of the post-earthquake track irregularity. spectrum was proposed considering earthquake and structural randomness. A mapping relationship between post-earthquake track irregularity. spectrum intensity index and post-earthquake driving performance index on bridge was established. A practical calculation method for the post-earthquake driving speed threshold of high-speed railway bridge, demonstrating the rationality and effectiveness of this method through case analysis. The results indicated that the post-earthquake driving performance index on bridge correlates approximately linearly with the intensity index of the post-earthquake track irregularity. spectrum. The post-earthquake driving performance targets on bridge can be categorized into safety and comfort targets. The post-earthquake driving performance evaluation criteria based on the comfort target impose stricter speed controls. The practical calculation method for assessing the post-earthquake capacity of high-speed railway bridge is simple, facilitates manual calculations, and possesses significant engineering applicability, providing a solid theoretical foundation for developing post-earthquake emergency plans and the performance-based seismic design of high-speed railway bridge.