Influence mechanism of the installation position of friction support on the dynamic characteristic of the subway station structure

Abstract

The aim of this research is to investigate the effect of friction pendulum isolator on dynamic performance of subway station structure. To this end, an actual bi-story, bi-span subway station structure is taken as the research object, a three-dimensional model considering the interaction effect between soil and subway station was proposed by using FEM software. Based on the FEM model, the seismic performance of the subway station structure with the friction pendulum bearings mounted on different positions was employed to elucidate the seismic isolation mechanism. It showed that: (1) The friction pendulum bearings can significantly reduce the relative displacement of the middle column and increase the anti-shear deformation capacity of the middle column. (2) The friction pendulum bearing can change the stress distribution of the subway station, and reduce the magnitude and concentration of stress of the columns in the isolation layer. (3) The friction pendulum bearings make the structure have more reasonable bearing capacity, as they can reduce the shear force and bending moment of the middle column significantly. It is suggested that the isolation bearing should be installed on the middle column of the ground floor of the station.