摘要
应用极限平衡拟静力方法进行地震边坡稳定性分析时,对粘聚力较小、内摩擦角较大的浅层滑坡而言,随着地震水平设计加速度值的增大,其临界滑动面基本保持不变;然而,对粘聚力较大而摩擦角较小的深层滑坡而言,随着地震水平设计加速度值的增大,临界滑动面越深、越宽,会呈现出发散现象,选取两个典型的均质土坡,设计了由浅及深的多条滑动面,分别采用极限平衡瑞典方法进行了相应安全系数的计算,同时比较了自重、地震力、粘聚力在抗滑力矩以及滑动力矩中所占比重的变动情况。研究发现:对于浅层滑坡,随着滑动面由浅及深的变化,粘聚力产生的抗滑力矩所占百分比下降幅度较大,自重产生的滑动力矩与总体抗滑力矩的比值下降幅度较大;而对于深层滑坡,随着滑动面由浅及深变化,自重产生的抗滑力矩所占百分比增长的幅度较大,地震力产生的滑动力矩与总体抗滑力矩比值增长幅度也较大。
This paper aims to find out why the critical slip surface determination by limit equilibrium method is unavailable for the slopes made of materials with larger cohesions and smaller internal friction angles.Two typical soil slopes were tested in this study and several slip of surfaces with different depth and width were assumed.The factor of safety related to each slip of assumed slip of surface was calculated by limit equilibrium Swedish method and the change of percentages of self-weight,earthquake force,and cohesion in the anti-sliding moment was compared.The results show that in the case of shallow sliding mode,the percentage of cohesion in anti-sliding moment decreases by a wide margin,and the ratio of sliding moment from self-weight to total anti-sliding moment decreases substantially with the depth of slip surface from up to down;for the deep sliding mode,however,the percentage of self-weight in anti-sliding moment increases by a big margin,and the ratio of sliding moment from earthquake force to total anti-sliding moment increases substaintially with the depth of slip surface from up to down.
出处
《世界地震工程》
CSCD
北大核心
2012年第2期57-63,共7页
World Earthquake Engineering
基金
国家自然科学基金项目(51008167)
山东省高等学校科技计划项目(J10LE07)
高等学校博士学科点专项科研基金(20103721120001)资助
关键词
边坡稳定分析
拟静力方法
极限平衡方法
安全系数
slope stability analysis; pseudo-static method; limit equilibrium method; safety factor