成层土边坡可靠度计算算法研究

Research on the calculation algorithm of layered soil slope reliability

考虑土体参数空间变异性的边坡可靠度分析大多基于单一的“均质”土体,而实际中边坡土体呈现明显的层状分布特征,目前在考虑土体参数空间变异性的成层土边坡的可靠度研究方面远远不够。本文基于ABAQUS软件和Python语言,编写了成层土边坡可靠度计算的算法。该算法可以实现非侵入式随机有限元分析,用户输入土体的空间变异性参数后,程序即可自动计算出边坡的可靠度指标。通过算例对开发的成层土边坡可靠度计算算法进行了验证,并研究了模拟次数、土体参数变异系数等对于边坡可靠度指标计算结果的影响。结果表明:开发的算法可以高效精确地计算出成层土边坡的可靠度,模拟次数达到1000次时,得到的可靠度指标已基本稳定。边坡的失效概率随土体参数变异系数的增加而增加,当忽略土体的分层特性时,将得到较小的失效概率,使得设计的边坡更加危险。

The slope reliability analysis considering the spatial variability of soil parameters is mostly based on a single"homogeneous"soil,but the soil of slope often presents obvious layered distribution characteristics in practice.At present,the research on the reliability of layered soil slope considering the spatial variability of soil parameters is far from enough.In this paper,based on ABAQUS and Python,the algorithm of layered soil slope reliability calculation is developed.The non-intrusive stochastic finite element analysis is realized in the algorithm.After inputting the spatial variability parameters of the soil,the reliability of the slope can be automatically calculated by the algorithm.The reliability calculation algorithm of layered soil slope is verified by an example,and the influence of simulation times and the variation coefficient of soil parameters on slope reliability is studied.The results show that the reliability of layered soil slope can be calculated efficiently and accurately by the developed algorithm,and the reliability obtained is basically stable when the simulation times reaches 1000.The failure probability of the slope increases with the increase of variation coefficient of soil parameters.When the layered characteristics of soil is ignored,the failure probability will be smaller,which makes the designed slope more dangerous.