Dynamic Response of Multi-Span Continuous Bridge Above Canyon Subject to SV and P Waves

The amplifying effect of ground motion in canyons is a major threat to the safety of ground structures. In order to further study the influence of ground motion on ground structures in canyons, a multi-span continuous bridge based on semi-circular canyons is built in this paper. Using viscoelastic artificial boundary method and ground motion input method, the seismic response of canyon terrain under SV wave and P wave of vertical incidence and oblique incidence are analyzed, and the ground motion time history is obtained, which is used as the seismic input at the pier support point. Under simplified soil-structure interaction, the dynamic response of a multi-span continuous bridge under earthquake is analyzed by using multi-point transient input method. The numerical results show that the canyon topography has an important effect on the ground motion, and the dynamic response of the canyon bridge is sensitive to the incident Angle and the incident wave frequency, and the time history difference of the multi-point seismic displacement input plays a major role in the response of the canyon bridge. At present, there are still many neglected factors in the research of canyon bridge ground motion, and further research needs to be supplemented. The results of this paper can provide reference for the seismic design of bridge structures built in complex terrain.