基于随机响应面法的岩质边坡稳定可靠度分析

Reliability analysis of rock slope stability based on the random response surface method

为客观描述岩质边坡中广泛存在的参数不确定性问题,同时解决传统的可靠度分析方法存在的不足,本文提出了基于随机响应面方法的岩质边坡稳定可靠度计算框架,并以一个典型的岩质边坡工程算例验证了本文方法的有效性。计算结果表明:2阶、3阶和4阶随机响应面法都能够较为有效计算岩质边坡结构稳定问题,计算结果与100万次蒙特卡洛方法的CDF曲线基本一致。此外,参数敏感性分析表明黏聚力c和内摩擦角φ变异系数的变化对失效概率的影响呈现正相关关系,单宽拉裂面面积z变异系数的变化对失效概率的影响呈现负相关关系。

In order to objectively describe the uncertainties of rock slope in practice,and to solve the limitations of the traditional reliability analysis methods,this paper proposed the reliability calculation framework of rock slope stability based on the random response surface method.A typical rock slope is taken as an example to verify the effectiveness of the proposed method.The results indicate that all the two-order,three-order and four-order random response surface methods can effectively calculate the reliability of the rock slope stability,which are basically the same as that of the 1 million Monte Carlo method.In addition,the sensitivity analysis of the parameters indicates that the variation of COV of cohesion and internal friction angle has a positive correlation with probability of slope failure,and the variation of COV of the area of the single-width tensile plane has a negative correlation with probability of slope failure.