EFFECT OF THE OBLIQUE INCIDENCE OF SEISMIC SV WAVES ON THE SEISMIC RESPONSE OF SUBWAY STATION STRUCTURE

Abstract

Based on the time-domain wave method and the explicit FEM coupled with viscous-spring artificial boundary condition, a 3-D input method for the plane seismic SV waves of oblique incidence is proposed. The numerical results of a half space demonstrates that this approach has a good precision. Then the proposed method is applied to investigate the seismic response of the Beigongmen Subway Station subjected to oblique incidence of seismic waves. The simulation results show that the dynamic responses of the subway station subjected to the action of obliquely incident seismic waves are clearly different from those due to vertically incident seismic waves. Oblique incidence of seismic wave has a significant impact on the vertical acceleration, despite of negligible influence on the horizontal acceleration. It can be found that the axial and shear forces at the columns vary obviously with increasing incident angel. Furthermore, there is significant increase in the first and third principal stresses at some key points of the sidewall. Therefore, the effect of obliquely incident seismic wave should be considered when studying the seismic response of subway stations.