Fuzzy random finite element reliability analysis of slope stability

It is necessary to carry out fuzzy random reliability analysis of slopes because there are fuzziness and randomness simutaneously.Based on the stochastic finite element reliability anaylsis of slope stability,a sensitivity analysis method of fuzzy random finite element reliability analysis of slope stability is presented.It can make use of the existing codes of stochastic finite element reliability anaylsis,can consider fuzziness and randomnress of parameters at the same time,and can get both the possible distribution of fuzzy reliability index and the positions of fuzzy slip surfaces.Since the method is based on the results of sensitivity analysis of stochastic finite element,the maximum and minimum values of the reliability index on a certain fuzzy cut can be obtained by running the stochastic finite element reliability analysis only twice,which means that this method is very efficient.It is demonstrated by two examples that the reliability index will decrease when the coefficients of variation increase.For a uniform slope,the positions of fuzzy slip surfaces are relatively concentrated.Therefore,there is a fuzzy slip zone in the uniform slope.However,for a two-layer nonuniform slope,the positions of fuzzy slip surfaces are affected by the failure mechanism,and the small variation will probably induce a relatively large change of the positions of slip surfaces.