强度随深度线性增长的不排水土坡稳定性分析  

Stability analysis of an undrained soil slope against the linearly increasing shear strength

作　　者：李萍[1,2] 张倩[1] 侯晓坤[1] 李同录[1,2] 

机构地区：[1]长安大学地质工程与测绘学院,陕西西安710054 [2]中国地质调查局西安地质调查中心/国土资源部黄土地质灾害重点试验室,陕西西安710054

出　　处：《水文地质工程地质》2016年第3期59-65,共7页Hydrogeology & Engineering Geology

基　　金：国家自然科学基金项目资助(41372329;41272283)

摘　　要：土在自然沉积的历史中,强度的形成主要受自重应力影响,因此许多学者发现黏性土的不排水抗剪强度有随埋深线性增长的特点。本文用弹塑性有限元结合强度折减法计算了全淹没、部分淹没和不浸水3种工况下不排水边坡在抗剪强度随深度线性增长条件下的稳定系数,利用稳定系数反演了稳定数。结果表明,对于全淹没和不浸水的边坡,有限元计算的稳定数和Hunter&Schuster的结果非常吻合。当部分淹没时,与美国陆军工程师团推荐算法所得结果差异较大,稳定系数的偏差在黏聚力增长梯度大时,可达30%。为此,本文基于弹塑性有限元的计算结果,提供了新的稳定数图谱,校正了美国陆军工程师团的方法。The soil shear strength in the procedure of the depositing history is mainly affected by gravity stress.Therefore,many investigators find that the undrained soil shear strength increases linearly with depth. With the elastic-perfect plastic finite element method combining the strength reduction method,the factor of safety of merged,partly merged and emerged soil slopes are calculated against the linearly increasing strength.Furthermore,the stability numbers are inversely analyzed. The results show that the stability number N calculated by FEM is almost the same as the results supplied by the Hunter Schuster against merged and emerged condition. When the slope is partly merged and the strength increasing gradient is big,N may decreases by 30% of the results showed in the manual of US Army Corps of Engineers. Thus,a series of the stability number N charts are supplied with the FEM to emend the results of US Army Corps of Engineers.

关 键 词：不排水边坡 抗剪强度 线性增长 稳定数 弹塑性有限元 

分 类 号：P642.22[天文地球—工程地质学]