山谷地形对入射SV波地震反应分析

Effect of Valley Topography on the Surface Ground Motion Subjected to Incident SV Waves

摘要:

基于黏弹性人工边界的显式动力有限元方法，研究了突出平台状山谷地形场地的地形效应，分析了山谷地形对地表地震动的影响。结果表明：（1）沿着地震动输入方向地表反应较其他方向上的反应强烈；（2）与单一凸起山体地形对地表地震动的放大效应相比，相邻地形的存在对地表地震动位移傅里叶谱谱比曲线的形状影响不大，但是对PGD有着较大的影响，随着相邻凸起山体之间距离的增大，该影响效应逐渐减弱。

Abstract:

The explicit finite element analysis method and the viscoelastic artificial boundary are used to study the topographic effect of valleys and the influence of valley topography on surface ground motion subjected to incident SV waves. The results show the following:(1) The incident direction of the ground motion can affect the site response, and the amplification of surface response along the incident direction of the ground motion is larger than those in other directions. (2) Compared with the amplification effect of single hill topography on the surface ground motion, the presence of adjacent hills has little effect on the shape of the Fourier spectral ratio curve of the ground displacement but has significant effect on the peak ground displacement value, and the effect decreases with the increase of the distance between adjacent hills.