Seismic response of underground stations with friction pendulum bearings under horizontal and vertical ground motions: Fid-Bau Portal

Seismic response of underground stations with friction pendulum bearings under horizontal and vertical ground motions

Chen, Zhiyi / Jia, Peng

Abstract The previous earthquake surveys show that central columns are the weak parts in subway stations during the earthquakes. Reducing the seismic responses of central columns can ensure the safety of stations. Setting friction pendulum bearings (FPB) at the top of central columns may be a good strategy. In this paper, based on a subway station in Shanghai, the FPB is simulated detailly. The isolation effect and mechanism of the FPB is studied with the three-dimensional dynamic time history analysis method. The shearing force and bending moment of the station central columns and the inter-layer displacement of the station during the earthquake are analyzed. The vertical ground motion of different amplitudes is considered. It is found that during the earthquake, the FPB can effectively reduce the maximum shearing force of the central columns and slightly reduce the maximum bending moment. At the same time, it will not cause a significant increase in the inter-layer displacement. The vertical ground motion will reduce the isolation effect of the FPB, and the degree of the reduction increases with the increase of the vertical ground motion acceleration amplitude.

Highlights • A series of 3D detailed numerical analysis on the underground station with friction pendulum bearings are conducted. • Effectiveness of friction pendulum bearings in the earthquake resistance of underground stations is proved. • Isolation mechanism of friction pendulum bearings under different ground motions is revealed. • Vertical ground motion will reduce the isolation effect of friction pendulum bearings.