Seismic Mitigation and Isolation Control of High-Speed Railway Extradosed Cable-Stayed Bridge Under Multi-point Ground Motion

Abstract

The influence of multi-point earthquake excitation on seismic mitigation and isolation control of high-speed railway extradosed cable-stayed bridge is studied. Taking the main bridge of yingshang super large bridge in Shangqiu-hefei-Hangzhou high speed railway as an example, finite element calculation model is established, and nonlinear dynamic time history analysis method is used. the calculation results of internal forces and displacements of the bridge are obtained when the seismic wave velocity is 250m/s, 500m/s, 750m/s, 1500m/s, 2500m/s and infinite (equivalent to uniform excitation) by using common bearing, viscous damper, lock-up devices and hyperboloid spherical seismic isolation bearings, respectively. The results show that: (1) The seismic response of the bridge is different under the action of different seismic wave velocity, when the wave velocity is 750 m/s, the internal force and displacement of the structure reach the peak value; (2) When the traveling wave effect is considered, the internal forces and displacements of the piers with three types of seismic isolation devices and common bearings have an increasing tendency; (3) the viscous damper and the hyperboloid spherical seismic isolation bearings have better seismic performance, while the lock-up devices increase the overall stiffness of the bridge, and thus amplify the internal force response of the structure.