三斜面法在重力坝深层抗滑稳定性分析中的应用

Three Sliding Planes Method for Deep Stability Analysis Against Sliding of Gravity Dam

针对重力坝深层抗滑稳定双斜面法存在的不足,探讨了重力坝深层抗滑稳定的三斜面法,将坝趾处分界面的倾角及其上抗力方向角作为未知量,在三个倾斜滑裂面上建立等安全系数法极限平衡方程,根据抗滑稳定安全系数极值条件,通过迭代和双重搜索试算求解最小的安全系数和最危险的滑裂面形态。计算结果表明,三斜面法更贴近实际工程的客观条件,比双斜面法更合理可靠、更具有普遍适用性。

Aiming at the defect of the double sliding planes method for deep stability analysis against sliding of gravity dam, this paper discusses three sliding planes method. This method takes the direction angle of the interface and the direction angle of the resistance on that plane in the toe of dam as the variables to establish limit equilibrium equations of three sliding planes based on the equal safety factor method. According to the extreme value condition of safety factor of stability against sliding, the minimum safety factor and the most dangerous slip mode are obtained by using the iterative method and dual search test algorithm. Comparing with the results of double sliding planes method, it shows that three sliding planes method is more closer to the objective conditions of the actual projects; it is more reasonable, reliable and general applicable.