复杂楔形体组合下的岩质高边坡稳定分析

Stability of High Rock Slope Formed by Complex Wedge

金沙江白鹤滩水电站左坝肩下游岩质高边坡受多组楔形体组合,其在拱端推力下的稳定性及工程施工下对左坝肩岩体的影响,对该工程意义重大。探讨了基于三维可变形离散元和大变形拉格朗日有限差分法相结合的方法,从定性和定量分析的角度,分析了白鹤滩水电站左坝肩下游楔形体的破坏运动模式、先后解体顺序、拱端推力下及工程施工下的稳定性及对左坝肩岩体的影响。根据上述两方法相结合的数值分析结果(安全系数小于1.1),并结合现场工程地质评价,认为在自然边坡及蓄水条件下,左坝肩下游高边坡属于潜在不稳定边坡,需进一步研究。

Baihetan Hydropower Station is located on Jinsha dam abutment is composed of several groups of wedge, thus, River. As the downstream high rock slope at left its stability under the thrust of arch and construction has great significance to the project. In this paper, 3D deformable discrete element method and 3D large deformable lagrange finite difference method are combined. The failure mode and the disintegration sequence of wedge are analyzed qualitatively and quantitatively. And its stability with fixed or changeable thrust of arch and its influence to the rock at left dam abutment are also analyzed. From numerical analysis result obtained by abovementioned two methods （safety coefficient being less than 1.1 ） and combination with the geological evaluation in situ, the high rock slope of the left abutment downstream is considered as a potentially unstable one under natural condition and pondage cases. So it is necessary to be further studied.