Numerical analysis of ground motion amplification coefficient under complex topography

Abstract

Topographic effect had an obvious influence on the ground motion, but the related regulations were vague in Chinese seismic code. Therefore, this paper explored the influence of topographic feature on the ground motion amplification coefficient (GMAC). The theory of viscoelastic artificial boundary was introduced and used to simulate the ground motion in different topographies. A comparison of the acceleration time-history curves between the simulation and the experiment was performed for illustrating the validity of the simulation method. Then, the influence of isolated topography on the GMAC was analyzed. The results showed that the GMAC was most sensitive to ridge topography. Further, considered with the complexity of real topography, the ground motions of tandem and parallel topographies were researched. The results showed that there was an interaction between adjacent topographies, and that lower-lying topographies should be given more attention due to their stronger earthquake response. Finally, this paper provided the modified suggestion of GMAC based on the researched results.