考虑参数空间变异性的非饱和土坡可靠度分析

发布时间：2018-03-14 13:30

本文选题：边坡　切入点：非饱和渗流　出处：《岩土力学》2014年09期 　论文类型：期刊论文

【摘要】：在考虑多个土体参数空间变异性的基础上,提出了基于拉丁超立方抽样的非饱和土坡稳定可靠度分析的非侵入式随机有限元法。利用Hermite随机多项式展开拟合边坡安全系数与输入参数间的隐式函数关系,采用拉丁超立方抽样技术产生输入参数样本点,通过Karhunen-Loève展开方法离散土体渗透系数、有效黏聚力和内摩擦角随机场,并编写了计算程序NISFEM-KL-LHS。研究了该方法在稳定渗流条件下非饱和土坡可靠度分析中的应用。结果表明:非侵入式随机有限元法为考虑多个土体参数空间变异性的非饱和土坡可靠度问题提供了一种有效的分析工具。土体渗透系数空间变异性和坡面降雨强度对边坡地下水位和最危险滑动面位置均有明显的影响。当降雨强度与饱和渗透系数的比值大于0.01时,边坡失效概率急剧增加。当土体参数变异性或者参数间负相关性较大时,忽略土体参数空间变异性会明显高估边坡失效概率。
[Abstract]:On the basis of considering the spatial variability of soil parameters, A non-invasive stochastic finite element method for stability reliability analysis of unsaturated soil slope based on Latin hypercube sampling is presented. The implicit function relationship between slope safety factor and input parameters is fitted by Hermite stochastic polynomial expansion. Latin hypercube sampling technique is used to generate input parameter sample points, and Karhunen-Lo 猫 ve expansion method is used to discretize soil permeability coefficient, effective cohesion force and internal friction angle random field. The calculation program NISFEM-KL-LHSis developed. The application of this method to the reliability analysis of unsaturated soil slope under steady seepage condition is studied. The results show that the non-invasive stochastic finite element method is a non-saturated method that takes into account the spatial variability of soil parameters. The spatial variability of soil permeability coefficient and rainfall intensity of slope have obvious influence on the slope groundwater level and the position of the most dangerous sliding surface. And when the ratio of permeability coefficient is greater than 0.01, When the variation of soil parameters or the negative correlation between parameters is large, ignoring the spatial variability of soil parameters will obviously overestimate the slope failure probability.
【作者单位】：武汉大学水资源与水电工程科学国家重点实验室;武汉大学水工岩石力学教育部重点实验室;香港科技大学土木与环境工程系;
【基金】：国家杰出青年科学基金项目(No.51225903) 国家重点基础研究发展计划(973)项目(No.2011CB013506) 教育部博士研究生学术新人奖资助项目(No.5052012206001)
【分类号】：TU43

【相似文献】