溃曲软硬相间顺层斜坡滑移-弯曲破坏机制分析

The mechanism analysis of sliding-bending destruction mode of consequent bedded slope in the alternatively distributed soft and hard rock layers

以白龙江苗家坝水电站库区巨型滑移-弯曲破坏模式的何家滑坡为例,在野外调研的基础上,利用理论公式、数值计算等手段,从地形、地应力、岩性组成和临空条件等方面分析了软硬相间层状斜坡产生滑移-弯曲模式变形破坏的成因机制。结果表明,研究区高、陡的地形条件、最大主应力平行斜坡走向的地应力条件,以及深部厚层软弱岩带的存在,是厚层状坚硬凝灰岩夹板岩斜坡孕育、发生滑移-弯曲模式变形破坏的主控因素。

The authors have investigated the engineering geological conditions of the large Hejia landslide destructed by sliding-bending mode in the Miaojiaba hydropower plant reservoir area, then analyzed the formation mechanism of the sliding-bending distortion and destruction mode of the consequent bedded slope in the thick and rigid rock mass from the landform and geostatie stress along with lithologieal compages and so on, at one time making use of theoretical calculation and numerical simulation. The conclusion is that the causation of distortion and destruction of the sliding-bending mode gestated and occurred in alternatively distributed soft and hard rocks is the tall and steep terrain along with the geostatic stress, the major principal stress parallel to slope-strike and the thick and pliable rock mass inside the slope.