考虑参数不确定性的台阶式边坡滑面强度参数反演分析

Back analysis of strength parameters for the slip surface of stepped slope considering parametric uncertainties

基于极限分析方法和概率分析理论,提出考虑参数不确定性的台阶式边坡滑面强度参数反演分析方法。首先,结合极限分析上限定理和强度折减法,推导得到台阶式边坡安全系数的隐式求解公式。为有效提高计算效率,利用随机响应面法获得安全系数显式表达函数,并令安全系数等于1的条件下,得到强度参数c和φ的反演关系式。在已知某一参数的统计规律基础上,通过参数的反演关系,获得待定参数的统计特征以及置信区间。结合工程实例,并与已有文献的结果对比,验证了本文所提出方法的有效性。

Based on the limit analysis method and probability analysis theory,this paper proposes a method for back analysis of the strength parameters for the slip surface of the stepped slope considering the parameter uncertainty.Firstly,combined with the limit analysis upper bound theorem and the strength reduction method,the implicit solution formula of the stepped slope safety factor was derived.In order to effectively improve the computational efficiency,the random response surface method was used to obtain the explicit function of the safety factor,and the inversion relation of the intensity parameters c andφwas obtained under the condition that the safety factor is equal to 1.Further,on the basis of the known statistical rule of a certain parameter,the statistical characteristics of the undetermined parameter and the confidence interval were obtained through the inverse relationship of the parameters.Combined with engineering examples and compared with the results of existing literature,the effectiveness of the proposed method was verified.