大坝边坡概率最危险滑面搜索的一种算法

Search Arithmetic of Dam Slope Probabilistic Critical Surface

在大坝边坡稳定性分析中,如果把岩体参数都作为定值来处理,可以通过计算最小安全系数来搜索到边坡的一个最危险滑面,称之为确定性最危险滑面。若把岩体参数作为随机变量来处理,通过计算最小可靠指标也可以搜索到另外一个最危险滑面,称之为概率最危险滑面。许多学者在研究中把这两个滑面作为一个面来处理,但实际工程中这两个面却不一致,通过对岩体不确定力学参数进行合理的组合及弱化,研究了这两个滑面之间的关系,提出了一种用计算安全系数来搜索概率最危险滑面的方法。并通过工程实例验证了该方法的可行性,结果表明:这是一种实用有效的搜索边坡概率最危险滑面的算法。

In dam slope stability analysis,if rock parameters are treated as fixed values,a surface of minimum factor of safety can be searched（referred to herein as the critical deterministic surface）.The other surface of minimum reliability index（referred to herein as the critical probabilistic surface） can also be searched if the rock parameters are treated as random variables.Many scholars consider the two surfaces as the same in their studies.But in fact,they do not generally coincide.In this paper,the relations between these two surfaces are investigated by reasonable weakening rock mechanical parameters.And an expedient technique is presented to search for the critical probabilistic surface by calculating the factor of safety.The technique is examined by a case study and is proved to provide a practical and efficient method to locate the critical probabilistic surface.