摘要
基于概率和统计理论,对适用于正常固结黏土边坡的不排水强度随机场进行模拟,得到不排水强度均值从0开始随深度线性增长的非平稳随机场模型.基于生成的非平稳随机场模型,建立考虑参数空间变异特性的正常固结黏土边坡随机有限元分析方法,从而揭示不排水强度参数空间变异特性对正常固结黏土边坡可靠度及破坏机制的影响规律.通过对比分析发现:边坡的安全系数较小时,若采用正态分布假设不排水强度,则会低估边坡的失效概率,得到非保守的结果;此时,存在一个最危险相关距离,边坡的失效概率最大.当边坡不排水强度变异系数较大时,结合随机有限元分析得到破坏机制比确定性分析得到的最深滑动面更深.
Based on probability and statistics theory,the random field of undrained strength for slopes in normally consolidated clays was simulated,and the non-stationary random field of undrained strength increasing linearly with depth from a zero value at the ground surface was obtained.Meanwhile,based on the generated non-stationary random field model,the random finite-element method for stability analysis of slopes in normally consolidated clays accounting for spatial variability of soil properties was proposed to investigate the effect of spatial variability of undrained strength on the reliability and failure mechanism of slopes in normally consolidated clays.By comparative analysis,it is found that for slopes with relatively low factors of safety,the assumption of normally distributed undrained strength may underestimate the probability of failure,leading unconservative results.Meanwhile,for slopes with relatively low factors of safety,there exists a worst-case spatial correlation length,which leads to the highest probability of failure.According to the failure mechanisms by random finite-element analysis,it is found that for slopes with relatively high coefficients of variation of undrained strength,the failure mechanism may be deeper than the deepest failure surface obtained by deterministic analysis.
作者
朱德胜
高越
费康
ZHU Desheng;GAO Yue;FEI Kang(College of Civil Science and Engineering, Yangzhou University, Yangzhou 225127, China)
出处
《华中科技大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2019年第7期29-33,共5页
Journal of Huazhong University of Science and Technology(Natural Science Edition)
基金
国家自然科学基金资助项目(51808484)
江苏省自然科学基金资助项目(BK20180934)
中国博士后科学基金面上资助项目(2018M642336)
江苏省高校自然科学研究面上资助项目(18KJB170022)
江苏省博士后科研资助项目(2018K137C)
关键词
空间变异
正常固结黏土
随机有限单元法
不排水强度
可靠度分析
spatial variability
normally consolidated clay
random finite-element method
undrained strength
reliability analysis
