中文摘要：

非侵入式的可靠度分析方法具有可以充分利用通用商业有限元软件、便于在实际工程中应用的特点，日益受到工程师们的青睐．本文提出了基于有限元强度折减法的边坡非侵入式可靠度分析方法，并研究了该方法在多层土质边坡可靠度分析中的应用．该方法可以考虑土体参数的空间变异性，基于通用有限元软件求解安全系数，借用随机响应面法实现高效的可靠度分析．结果表明，基于有限元强度折减法的非侵入式边坡可靠度分析方法不仅能够有效地考虑土体参数空间变异性对边坡可靠度的影响，而且能够自动搜索到非圆弧形最危险滑面，所提方法为解决考虑空间变异性的多层土质边坡可靠度问题提供了一条有效的分析途径．提出的改进概率配点法能够有效地提高奇数阶随机响应面的计算精度．采用圆弧形滑面可能会明显高估边坡可靠度水平，因此，十分有必要采用无需事先假定滑面形状的有限元法进行边坡稳定性分析．此外，Sobol指标能够有效地反映随机变量的敏感性，为边坡设计方案优化提供参考依据．

英文摘要：

A non-intrusive reliability analysis method has been highly valued by engineers due to its practicability with utilizing commercial finite element software. The method based on strength reduction finite element method （FEM） is proposed to evaluate the reliability of multi-layered slopes, which considers spatial variability of soil properties, employs commercial finite element software to calculate the safety factor, and uses stochastic response surface method （SRSM）to perform efficient slope reliability analysis. The results indicate that the proposed method can not only take into account the influence of spatial varying soil properties on the slope reliability, but also automatically search for the non-circular critical slip surface, which provides an effective way for solving reliability problems of multi-layered slopes with spatially variable soil properties. Secondly,the modified probabilistic collocation method can improve the calculation accuracy of odd order SRSMs. Furthermore, it is of importance for slope stability analysis with no assumption relating to the geometry of critical slip surface a prior, since the circular slip surface may overestimate the slope reliability. Additionally, Sobol indices can effectively rank sensitivities of input random variables, and provide a reference for the optimal design of slopes.