锦屏一级水电站降雨入渗条件下左岸边坡稳定性分析

Stability Analysis for Left Bank Slope of JinpingⅠ Hydropower Station under Rainfall Infiltration

依托锦屏一级水电站左岸高边坡工程,选取典型计算剖面进行二维数值模拟计算,分析了边坡在自然条件和开挖完成时的应力、位移和稳定性。结合Mohr-Coulomb准则和Fredlund强度理论分暴雨和久雨工况对比分析了边坡在加固与不加固情形下安全系数随降雨时间的变化情况。结果表明,坡面防水及坡体排水对提高边坡稳定性具有明显作用;随着降雨的持续,稳定系数逐渐降低,降雨结束一段时间后稳定系数降至极低点,随后再缓慢回升。

Relying on the project of the high slope at the left bank of Jinping Ⅰ Hydropower Station ,the typical calcula-tion sections are selected to do the 2D numerical simulation calculation so as to analyze the stress ,displacement and sta-bility of the slope under natural conditions and when the excavation is completed .Meanwhile ,the safety factor variations with rainfall time under both rainstorm and long-lasting rainfall are analyzed based on the combination of Mohr-Coulomb criterion and Fredlund strength theory .The results indicate that the slope surface waterproof and slope drainage could play an obvious role in improving the slope stability ;as the rain continued ,the stability coefficient would be decreased gradually and it would be decreased to the minimum point in some time after the rainfall ,then it would be risen slowly af-ter that .