水库诱发岸坡失稳的机理及其预测

THE RESERVOIR-INDUCED SLOPE FAILURE MECHANISM AND PREDICTION

水库蓄水诱发岸坡变形失稳是经常遇到的问题。岸坡在淹没饱和过程中,岩石强度的降低及裂隙的扩展和土体抗剪强度的降低将随之发生在岩质岸坡和松散层岸坡中。岸坡的部分淹没导致岸坡内部力学平衡的打破,进而诱发变形的出现或在某些部位应力集中。潜在不稳定体的几何形态、斜坡结构及材料力学特性、库水位波动速度将决定岸坡的变形失稳方式。边坡稳定性变化幅度受控于不稳定体的几何形态、水文地质条件及潜在破坏面的强度。三峡库区岸坡再造形式将是多样的,其变形机理及危害也不相同。

Many slope failures have occurred due to the water reservoir. The material strength weakness and the hydraulic effect are two important provocative factors. The slope deformation and failure manner are linked with the geometry of the potentially instable rock - mass, the mechanics of the materials and the water level fluctuation. The slope stability is controlled by the geometry of the instable rock - mass, the hydrogeological condition and the shear resistance of the sliding surface. The slope reform in the Three Gorges reservoir will be variable, the deformation mechanism and the failure induced will also be different.