复杂地基下重力坝抗滑稳定可靠度分析

针对复杂地基条件下重力坝不同抗滑稳定评估方法的适应性问题及传统刚体极限平衡法中多滑面功能函数难以显式建立的现状,在传统安全系数评估方法的基础上,构建了失效通道的抗滑稳定功能函数,结合响应面方程和验算点法进行抗滑稳定可靠度分析,提出了考虑失效模式间相关性的基于条件概率降维法(DRMCP法)的复杂地基重力坝多通道失效的串联体系可靠度计算方法,实现了对复杂地基情况下的高混凝土重力坝抗滑稳定安全可靠性进行分析。某高重力坝实例分析结果表明,地基材料的复杂性、变异性造成同一滑移通道安全系数与可靠度并非完全对等,复杂地基情况下体系可靠度主要取决于最薄弱通道的单点可靠度。

Reliability Analysis of Anti-sliding Stability of Gravity Dam under Complex Foundation

Aiming at the adaptability of different anti-sliding stability evaluation methods for gravity dams under complex foundation conditions and the difficulty of establishing multi-sliding surface function explicitly in traditional rigid body limit equilibrium method, the anti-sliding stability function of failure passage was constructed on the basis of traditional safety factor evaluation method. The anti-sliding stability function of failure passage was combined with response surface equation and checking point method. Based on DRMCP reliability analysis, a series system reliability calculation method for complex foundation gravity dam with multi-channel failure was presented. The reliability and stability of the high concrete gravity dam under complex foundation conditions were analyzed. The calculation results of a gravity dam show that the safety factor and reliability of the same slip channel are not exactly the same as the complexity and variability of the foundation material. The reliability of the system is mainly determined by the single point reliability of the weakest channel.