茨哈峡水电站Ⅵ号变形体破坏机制及稳定性分析

Analysis of the mechanism of deformation,failure and stability of the Cihaxia Hydropower Station No.6 deformed rock mass

阐述茨哈峡水电站Ⅵ号变形体发育的地质环境,描述该变形体的主要特征:岩层倾角自岸坡水平向里由缓变陡;倾倒、弯曲、拉裂变形显著;弹性波速较低;变形体坡面岩体破碎并经常发生垮塌破坏现象;坡顶发育大型拉裂槽及多达几十条的反向错坎裂缝。根据这些特征,运用地质力学分析法及有限元概念模型阐明了变形体的形成机制。通过有限元对地质原型的模拟研究,进一步验证了该变形体的各种变形破坏现象。

The geological environment of the No. 6 deformed reek mass of the Cihaxia Hydropower Station is described. The main deformation behaviors are described, including the strata inclination that changes from gentle to steep in the horizontal direction from the bank slope to the inside of the deformation mass, the obvious toppling, the bending and tensile deformation, the low speed of elastic waves, the crushing and frequent collapse on the surface of the deformation mass, the appearance of a large trough due to tensile fracture, and the many inverse fissures of displacement on the top surface of the deformation mass. According to the above characteristics, the deformation mechanism of the rock mass is described using the geomeehanics analytic method and the conceptual model of the finite element method （FEM）. Variotts deformation and failure phenomena of the deformed rock mass are verified with the simulation of the geological model through FEM.