两河口水电站泄洪出口边坡渗流及稳定性计算分析

Seepage Calculation and Stability Analysis of Outlet Slope for Lianghekou Hydropower Station

在分析两河口水电站泄洪洞出水口边坡工程地质条件的基础上,研究了边坡岩体的渗透特性,结合雾化降雨试验资料、采用饱和非饱和渗流有限元方法计算并分析了边坡雾化雨条件下渗流场的变化规律,同时引用非饱和强度理论并运用Sarma极限平衡方法分析了雾化雨对边坡稳定性的影响,所获得结论可为正确评价边坡岩体的稳定性、合理可行的工程控渗及边坡加固措施提供依据。

Based on the analysis of geological conditions of the outlet slope of Lianghekou Hydropower Station,the permeability of slope rock masses is researched indetail. Combined with the experimental data of atomized rainfall, the basic rule of the slope seepage field under the condition of atomized rain is gotten by the method of FEM in unsaturated seepage. Caused by atomized rain,the pressure head at superficial place of the slope is raised and transient saturated zone can exist at the base of slope and the slope where is gentle. Without regard to the drainage facilities, the pressure head can reach about 200 m at transient saturated zone and the horizontal range is 20-60 m. There is scarcely any influence on the deep seepage field; then,based on unsaturated strength theory, slope stability influenced by atomized rain is analyzed by using Sarma method,and the stability factor of each sliding mode decreases by 27.0 % in the process of atomized rainfall.