同时考虑张拉-剪切破坏的边坡稳定性分析  

Slope Stability Analysis Considering Tension-Shear Failure

作　　者：张谭 林松涛[1] 郑宏[2] 陈彦江 ZHANG Tan;LIN Songtao;ZHENG Hong;CHEN Yanjiang(Central Research Institute of Building and Construction Co.,Ltd.,MCC Group,Beijing 100088,China;Faculty of Architecture,Civil and Transportation Engineering,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]中冶建筑研究总院有限公司,北京100088 [2]北京工业大学城市建设学部,北京100124

出　　处：《济南大学学报（自然科学版）》2023年第5期591-598,共8页Journal of University of Jinan(Science and Technology)

基　　金：国家自然科学基金项目(52130905)。

摘　　要：针对目前边坡稳定性分析的强度折减法中广泛采用的Mohr-Coulomb准则仅考虑剪切破坏会过高估计边坡土体的抗拉强度,与实际工程中常见的位于坡体后缘的拉裂缝不符的问题,引入土体的张拉-剪切复合屈服准则,分别采用Mohr-Coulomb准则、Rankine准则考虑剪切、张拉作用的影响;根据张拉-剪切复合屈服准则的非光滑性,通过将非光滑屈服面的塑性本构积分简化为混合互补问题,提出用于弹塑性本构积分的投影收缩算法。结果表明:在分析边坡的稳定性时,不考虑张拉破坏会过高估计边坡的安全性并且安全系数的差值随着坡角的增大而逐渐增大,最大差值达到20%;对于含软弱夹层的分层边坡,即使边坡的坡角较小,是否考虑张拉破坏的边坡后缘的破坏特征仍存在显著区别。In view of the problem that Mohr-Coulomb criterion widely used in strength reduction method for slope stability analysis at present overestimated tension strength of slope soil mass due to only considering shear failure,and was inconsistent with tensile cracks at the rear edge of slope commonly seen in practical projects,tensile-shear composite yield criterion of soil mass was introduced.Mohr-Coulomb criterion and Rankine criterion were respectively used to consider effects of shear and tension.According to non-smoothness of tension-shear composite yield criterion,a projection contraction algorithm suitable for elastoplasticity constitutive integral was established by simplifying plastic constitutive integration of non-smooth yield surfaces to a mixed complementary problem.The results show the safety of slope is overestimated without considering the tensile failure when analyzing the stability of slope,and the difference of safety factors gradually increases with the increase of slope angel with the maximum difference of 20%.For layered slopes with weak intercalated layers,even if the slope angel is small,there is still a significant difference in failure characteristics of slope rear edge with or without considering the tensile failure.

关 键 词：边坡 有限元强度折减法 张拉-剪切破坏 非光滑屈服面 

分 类 号：TU431[建筑科学—岩土工程]