同时考虑基本变量和极限状态模糊性的边坡模糊随机有限元可靠度分析

FUZZY RANDOM FINITE ELEMENT RELIABILITY ANALYSIS OF SLOPESTABILITY WITH FUZZY BASIC VERIABLES AND FUZZY STATES

基于边坡稳定有限元分析的滑面应力法,研究同时考虑基本变量模糊性和极限状态模糊性的边坡稳定模糊随机有限元可靠度分析方法。对于基本变量的模糊性,采用等价变换的方法将模糊变量等价变换为随机变量;对于极限状态的模糊性,基于概率积分法研究了模糊破坏概率及模糊随机可靠指标的求解方法。本方法既可求解边坡剖面上各有限单元的模糊随机可靠指标,亦可求解边坡整体最小可靠指标及临界滑面的位置;既可考虑基本变量的模糊性,又可考虑极限状态的模糊性,是常规的随机有限元可靠度分析方法的推广。当不考虑基本变量和极限状态的模糊性时,它即退化为随机有限元可靠度分析方法。

Based on slip surface stress method of finite element analysis of slope stability,the fuzzy random reliability analysis method of slope stability is studied with consideration of both the fuzziness of basic variables and limit states.For the consideration of the fuzziness of basic variables,the method of equivalent transformation is used for the transforming from fuzzy variables to random variables.For the consideration of the fuzziness of limit states,the method of probabilistic integral is used for the calculation of fuzzy failure probability and fuzzy random reliability index.The proposed method can not only calculate the fuzzy random reliability index of each finite element,but also the minimum reliability index of the whole slope and the corresponding position of the critical slip surface.This method can consider the fuzziness of both the basic variables and the limit states,and it is an extension of the normally used stochastic finite element reliability analysis method.If the fuzziness of the basic variables and the limit states are not considered,the method will turn into the normally used stochastic finite element reliability analysis method of slope stability.