倾斜基岩上的边坡破坏模式和稳定性分析  

Failure mode and stability analysis of soil slope on inclined bedrock

作　　者：徐光明[1] 邹广电[1] 王年香[1] 

机构地区：[1]南京水利科学研究院土工研究所,江苏南京210024

出　　处：《岩土力学》2004年第5期703-708,共6页Rock and Soil Mechanics

摘　　要：应用离心模型试验对工程中被颇为关注的带有与边坡走向一致的倾斜基岩面,且在该基岩面存在软弱夹层的边坡的稳定性和破坏模式进行了比较详细地研究,并用极限平衡分析方法对试验结果进行了计算分析。模型试验结果表明,该类边坡失稳时,紧贴岩面的软弱夹层就成为滑动破坏面,因而边坡整体沿基岩面向下滑动,且侧向水平位移各处基本一致,表现出典型的平移滑动破坏模式。将稳定安全系数的实测结果与按平移滑动破坏模式的极限平衡分析方法的计算结果相比较后发现,两者相当地吻合,证实了按平移滑动破坏模式所作的极限平衡分析,能良好地预测边坡平移滑动破坏情形下的稳定安全系数。A physical study of slope stability has been done by means of geotechnical centrifugal model test to investigate the influence of presence of soft stratum immediately over inclined bedrock on slope stability and failure mode. And the limit equilibrium method based on the failure mode of translational slide is used to predict the factor of safety against sliding simulated in the model tests. It is found from the centrifugal model tests that, in the case of a thin layer of soft soil with lower shear strength over the inclined bedrock, the slip plane is close to the bedrock, and that lateral displacement at failure is of equal value almost throughout the entire slope mass, exhibiting a typical failure mode of translational slide. It is also seen that, in the case of absence of soft soil layer over the inclined bedrock, the slip plane is away from the inclined bedrock at a distance, and that the slope mass above the slip plane is of translational slide whereas the slope mass under the slip plane is of forward tilt slide. It is shown that the stability of slope is not solely determined by the average shear strength of slope soil mass when soft stratum is present over bedrock. It is confirmed that the suggested limit equilibrium analysis is able to predict the factor of safety of a slope on inclined slope by comparison of the factor of safety measured by physical centrifugal model test and the calculated one.

关 键 词：边坡稳定性 软弱夹层 破坏模式 离心模型试验 极限平衡法 

分 类 号：U416.1[交通运输工程—道路与铁道工程]