高速列车动载下岩溶盾构隧道动力响应分析

为了更好地分析岩溶盾构隧道在高速列车荷载作用下盾构管片及地层的动力响应，利用FLAC3D有限差分软件对其进行了数值模拟。研究表明:地层竖向位移分布呈不对称状态，左侧竖向位移较小，右侧竖向位移较大，位移等值线斜向上发展。管片下部与左侧围岩竖向位移衰减较快，上部及右侧围岩竖向位移衰减较慢。行车动载引起的管片环位移响应主要发生在竖向，总体趋势为右侧比左侧大，所以管片有整体顺时针旋转趋势，下部竖向位移大于上部竖向位移，管片环发生竖向椭变。

Analysis on Dynamic Response of Karst Shield Tunnel under High-speed Train Load

In order to make better analysis of dynamic shield tunnel under high-speed train load, this paper response of shield segments and strata around karst used FLAC3D finite difference software to conduct numerical simulation. The study result shows that the stratu has such asymmetric distribution of vertical displacement that the left-side vertical displacement is small but the right-side one is large with the displacement contour presenting a inclined development upward. The vertical displacement of the surrounding rock at the lower part and on the left side of segments damps quickly, but that at the upper part and the right side damps slowly. The displacement response of the segment rings caused by dynamic train load occurs mainly in vertical direction and the overall trend is such that the response on the right is larger than that on the left, hence the segments tend to rotate clockwise as a whole, and the vertical displacement at the lower part is lager than that at the upper part, thus vertical elliptical deformation arises on the segment rings.