四川某水库大坝左坝肩边坡变形破坏机制及整治对策探讨

以现场考察和变形监测资料为依据，探讨一个下部有软弱基底，上部为硬脆性坡体的“二元结构”边坡的变形破坏问题，揭示这类边坡的变形总是以下部软弱岩体的不均匀压缩流变为先导，进而引起上部硬脆性坡体的拉裂与倾倒，最终通过渗入水的作用，使下部承载状况已进一步恶化了的软弱岩体，沿剪应力集中带发生剪切破坏而导致整个变形坡体的下滑。

RESEARCH ON THE DEFORMATION MECHANISM AND TREATMENT MEASURE OF THE LEFT ABUTMENT SLOPE AT A DAMSITE IN SICHUAN

Based on the data obtained from field observations and deformation monitoring,this paper deals with the deformation and failure of a double-decked slope composed of soft rock strata in its lower part and hard-brittle rock strata in its upper part.It is demonstrated that the deformation of this kind of slopes is always initiated by the non-homogeneous rheological compression of the lower soft rock strata,leading to the tension fracture and toppling of the upper hard rock strata, and at last the sliding of the whole deformed body will be caused by the shear failure along the stress-concentration zone in the lower soft rock mass under the actions of the gravitational loading and infiltration water.