提出了工程地质分析与三维反演模拟相结合的方法,以揭示边坡地震渐进破坏的失稳过程和失稳机制。结合西南某水电站顺层岩质高边坡工程实例。研究该高边坡地震后工程地质特性,恢复边坡震前的地形地貌,建立地震前未滑塌边坡的三维模型。利用FLAC^3D对模型进行动力.时程响应分析,绘制位移、速度、加速度三量放大系数等值线图,判断地震破坏位置。数值模拟结果与边坡实际滑塌情况相符。应用工程地质分析与三维反演模拟结合的方法,揭示了边坡后发型阶段性逐级滑塌的破坏机制以及大夹角折线形的后缘破坏面形状。三维数值反演研究中采用的岩体动力参数,为正演研究提供了参考。
The failure of a high rock slope is a common phenomena in nature, however it is a very complex subject which is worth studding. This paper presents an analytical method, which is a combination of methods of engineering geology and back analysis, for simulating the deformation behaviors in earthquake and providing some useful insights into the deformation mechanisms. Based on a project of a high dip bedding rock slope of a hydropower station in Southwest China, at first the engineering geological characteristics of the high slope is analyzed. Secondly, a 3D numerical model of the slope before the earthquake is established by estimating the ancient topographic and morphologic characteristics and reinstating the glided mass. Then the software FLAC^3D is used to analyze the seismic time-history response of this slope. The calculated results accord with the situation happened in the earthquake. Finally, this 3D dynamic response back analysis method can provides the dynamic coefficients of rock mass which can be used in the next numerical modeling for this slope.