基于二次逆可靠度分析方法的边坡稳定性研究

Slope Stability Research Based on the Method of Quadratic Inverse Reliability Analysis

通常边坡工程中大部分的可靠度求解都是正向问题,即在已知边坡参数信息的前提下计算可靠度指标。但是随着工程上可靠度指标的变化,其相应的设计参数也应发生改变。基于反向推演工程参数的需要,本研究在一次逆可靠度的基础上,进一步提出了二次逆可靠度方法,结合极限平衡理论中的简化Bishop法,建立了基于二次逆可靠度的边坡稳定性分析方法并给出具体求解流程。将其运用至实际工程,结果表明:因考虑了边坡参数的不确定性,该方法不仅能适应工程目标可靠度指标的变化,并且相对于应用广泛的一次逆可靠度法而言,其精度有所提高,更能精确控制工程的失效风险和成本。

Generally,most of the reliability solutions in slope engineering are forward problems,that is,the reliability index is calculated under the premise of known slope parameter information.But with the change of engineering reliability index,the corresponding design parameters should also change.Based on the need for reverse deduction of engineering parameters,this study further proposes a secondary inverse reliability method on the basis of the primary inverse reliability,and combines the simplified Bishop method in the limit equilibrium theory to establish a slope based on the secondary inverse reliability.Stability analysis methods and specific solution procedures are given.Applying it to actual engineering,the results show that due to the uncertainty of slope parameters,this method can not only adapt to the change of the engineering target reliability index,but also has the accuracy compared to the widely used first-order inverse reliability method.The improvement can more accurately control the failure risk and cost of the project.