弹性波入射时半圆弧凹陷地形对地表位移影响研究
Influence of a Semi-circular Canyon Site on Ground SurfaceDisplacement Due to Incidence of Elastic Waves

基于数值模拟方法系统研究脉冲与正弦SH波及P波垂直入射半圆弧凹陷场地时的地表位移响应，并与相应解析解进行了对比分析。P波入射时，半圆弧凹陷场地由于P波与反射SV波的干涉产生Rayleigh波，会对场地自由表面的稳态位移响应幅值产生较大影响。凹陷内部的归一化Z向位移幅值相比没有考虑Rayleigh波生成时有较大的不同，其在凹陷边缘处没有什么变化，而在凹陷向两侧延伸的方向，会有压缩作用；归一化X向位移幅值在凹陷内部无太大变化，在凹陷向两侧延伸的方向，会有波动状的归一化X向位移幅值。
The surface displacement responses of a semi-circular canyon site subjected to normal incidence of SH and P waves were studied using a numerical simulation method. Results were compared and analyzed with the corresponding analytical solutions. Subjected to P waves, the Rayleigh wave was generated on the semi-circular canyon site, and had certain influence on the displacement response amplitude of the free surface of the site. In the canyon, the normalized displacement amplitude in the Z direction was quite different from that without consideration of the Rayleigh wave, though there was no change at the canyon edge. There was a compression effect in the extension direction from the canyon to both sides. The normalized displacement amplitude in the X direction had no significant change in the canyon, but changed in the extension direction from the canyon to both sides