地震体波斜入射下的断层台阶地震反应分析

应用显式有限元法对倾斜断层台阶在地震体波斜入射下的地震反应进行了数值模拟。模拟结果表明，P波入射时的竖向运动分量和SV波入射时的水平向运动分量在台阶上角点处存在极大值、在台阶下角点处存在极小值，同时在上下台面还出现由角点激发、向台阶外传播的转换体波与面波。这一结果说明，在断层台阶场地建设重大工程时应离开上角点一定距离，并考虑上下水平表面地面运动的差异性。

Seismic Response Analysis of Fault Step Subjected to Obliquely Incident Body Waves

The explicit finite element is used to simulate the seismic response of an inclined fault step subjected to obliquely incident P and SV waves. The numerical result shows that the amplitudes of vertical component when incident wave is P wave and the horizontal component when incident wave is SV wave are maximal at top corner and minimal at bottom corner, and the converted body waves and surface waves occur on the upper and lower horizontal surface, which propagating away from the fault step. This result shows that the important projects should keep away from the top corner of a fault step, and the difference of ground motion between the upper and lower horizontal surfaces should be considered in the design of the important projects crossing the fault step.