基于灰色关联度法和强度折减法的边坡稳定性影响因素敏感性分析

Sensitivity analysis of factors influencing slope stability based on grey correlation and strength reduction method

针对强度折减法采用单一折减系数的不足,前人给出了双强度折减法的概念,但c、φ值以及其他参数在具体边坡失稳过程中发挥的作用还不得而知。为了研究不同土体本构参数对强度折减法的影响,本文基于灰色关联分析方法,对土体内摩擦角φ、黏聚力c、弹性模量E、泊松比μ、剪胀角Ф的影响程度进行分析。运用传统强度折减法模拟,分析影响因素与边坡稳定性系数之间的相关程度,剖析有限元中边坡稳定性的敏感要素,为双强度折减法提供参考并提出建议。结果表明,影响因素的敏感性大小按从大到小排列依次是:φ、c、μ、Ф、E;通过不同参数下的边坡滑动面对比,μ、Ф对于边坡的临界状态有较大影响,在强度折减时需要考虑这两者的影响。

To overcome the shortcoming of using single reduction coefficient in strength reduction method of finite element method,the predecessors introduce the concept of double strength reduction method,but the role of candφvalue and other parameters in specific slope failure is still unknown.For a better understanding of the influence of soil parameters on the traditional reduction method,friction angleφ,cohesion c,elastic modulus E,Poisson’s ratioμand dilatancy angleФof soil is analyzed based on grey relational analysis method.The traditional strength reduction method is used to simulate and analyze the correlation between influencing factors and slope stability coefficient.The sensitive factors of slope stability in finite element method are analyzed,which can provide reference and proposal for double strength reduction method.The results show that the sensitivity of the influencing factors from large to small isφ,c,μ,Ф,E;by comparing the sliding surfaces of slopes with different parameters,the critical state of slopes is greatly affected by the factorsμandФ,which should be considered in strength reduction method.