基于局部强度折减法的某水电站边坡稳定性分析

Stability Analysis of Slope in a Hydropower Station with Local Strength Reduction Method

边坡的稳定性问题一直是水电工程研究的重点和难点,目前普遍采用整体强度折减法进行分析,其考虑了对所有岩土体单元强度折减,与实际不相符合。基于局部强度折减法基本理论,采用有限元软件对某含有软弱夹层的水电边坡进行稳定性分析评价。结果表明:自然工况下,边坡稳定安全系数为1.28,边坡基本稳定;但在降雨过后,软弱夹层抗剪强度迅速降低,塑性区贯通,边坡稳定安全系数仅为0.96,边坡将沿着软弱结构面滑动;对上部危岩体进行加固后,边坡稳定安全系数分别提高75.8%和90.6%,塑性区范围减小。计算结果可为同类边坡工程的稳定性评价和加固施工提供借鉴。

The problem of slope stability was always the emphasis and difficulty of hydropower engineering research, the overall strength reduction method was used widespread, which considering all the rock soil units and was not consistent with the actual. Based on the theory of local strength reduction method,the finite element software was used to analyze the stability of a hydropower station slope containing weak interlayer, the results indicated that： the slope stability safety coefficient was 1. 28 and the slope was stable under natural conditions; but after the rain, the weak interlayer shear strength decreased rapidly and the plastic zone ran through, safety factor of slope stability was only 0. 96, the slope would slide along the weak structural surface. When the upper parts of the dangerous rock body were strengthened, the safety factor of slope stability increased respectively by 75. 8% and 90. 6%, and the plastic zone also reduced.The results could provide some reference for the stability analysis and reinforcement construction of similar slope engineering.