考虑行波效应的三维河谷场地长周期地震动响应分析

Traveling Wave Effect on the Seismic Response of 3D Valley Topography Site under Longperiod Seismic Excitation

选取3条典型的基岩长周期地震波和两条常见的普通地震波,分别进行了一致输入和行波输入作用下某河谷地形场地的三维有限元地震反应分析,利用等效线性化方法考虑了土体材料的非线性特质,并对比了长周期地震波和普通地震波作用下场地反应的差异。分析结果表明,无论是一致输入还是行波输入,长周期地震作用下场地水平向加速度反应均大于普通地震波,竖向地震反应则相反。考虑行波输入时水平向加速度反应有所减弱,但竖向地震反应明显增大,研究结果可为相关工程提供参考。

In this paper,three typical bedrock long-period seismic waves and the other two common waves are selected in three dimensional seismic responses analysis of a valley topography site under uniform excitation and traveling wave excitation,the equivalent-linear analysis method is used in simulation of soil’s non-linear properties,the differences of seismic responses between long-period seismic waves and common waves are analyzed.The result shows that whenever under uniform excitation or traveling wave excitation,comparing with common waves excitation,the horizontal acceleration response is increased and the vertical acceleration response is decreased when under long-period seismic waves excitation.Furthermore,comparing with uniform excitation,the horizontal acceleration response is decreased and the vertical acceleration response is increased when under the excitation of traveling waves.The conclusions may be refered to the relevant engineering.