某公路边坡稳定系数的强度折减法分析

Analysis of strength reduction method for typical highway slope stability factor

针对湖北境内某高速公路边坡遭遇连续降雨出现失稳的问题,基于有限差分的强度折减法分析该高速公路边坡在自然状态、开挖、非正常工况(暴雨)下的安全系数,同时采用有限单元应力法对所得安全系数进行验证。在此基础上,分析非正常工况下边坡的破坏形式,获得该工况下边坡的潜在滑动面位置。结果表明,三种工况下的安全系数分别为1.22、1.04和0.88;有限单元应力法所得结果与强度折减法基本一致;经加固后,边坡的安全系数为1.21,达到了设计要求。该研究为失稳边坡加固提供了依据。

In response to the highway slope instability resulting from continuous rainfall in Hubei Province, this paper introduces the application of strength reduction method based on finite difference method to analyze slope safety coefficient occurring in the natural condition, excavation and abnormal condition （ rainstorm）, together with the verification of the safety coefficient using the finite element stress method. The paper features an analysis of failure form of slope subjected to abnormal working condition and the insight into potential sliding location. The results show that the safety coefficient associated with the three working conditions are 1.22, 1.04 and 0.88 respectively. The finite element stress method pro- duces the basically the same result as strength reduction method. The slope subjected to reinforcement has the safety coefficient of 1.21, up to the design requirement. The study serves as a basis for unstable slope reinforcement.