降雨条件下顺层岩质边坡稳定性研究

Stability Analysis of Rainfall-induced Rock Bedded Slope

以西南山区某边坡为原型,对岩质边坡渗流特性和雨水入渗过程进行了分析,对降雨入渗对岩质边坡的作用进行了探讨,利用MIDAS/GTS研究边坡在不同降雨强度下孔隙水压力变化规律,以及降雨和不同支挡形式对边坡稳定系数的影响。研究结果表明:随着降雨历时的增加,孔隙水压力迅速增大,当孔隙水压力增长到一定大小后,孔压不再增加,此后孔压变化很小,坡面达到饱和状态;降雨对边坡稳定影响较大,含软弱夹层的岩质边坡稳定性主要取决于软弱夹层的强度;支挡结构限制了滑体位移,具有良好的加固效果,支挡形式越强,边坡越稳定;岩层倾角越小,边坡越稳定。研究结果可为顺层岩质边坡的科研、设计和施工提供参考。

Based on a treatment slope project in southwest China, this paper analyzed the characteristic of seepage flow for rock slope and the process of rainfall infiltration. The effect of rainfall infiltration on rock slope was studied. It also analyzed the variation of seepage field under different rainfall intensity and slope stability effected by rainfall and different retaining structures based on Midas/GTS. The results showed pore water pressure increased to a certain value rapidly with rainfall duration increasing and it changed little later when water content of slope surface reached to saturated state. Rainfall played an important role on slope stability, and rock bedded slope stability depended on strength of weak layers. Retaining structures limited the displacement of slip and had a good reinforcement effect. Furthermore, the slope stability increased with retaining form becoming stronger and it also increased with obliquity of rock layer becoming smaller. The results could provide a reference for study, design and construction of rock bedded slope.