金川电站左岸引水发电系统进水口边坡块体稳定性分析

Stability analysis on rock blocks of slope for inlet diversion tunnel at left bank of Jinchuan Hydropower Station

边坡开挖为边坡岩体中的岩石块体创造了新的临空条件,块体的初始稳定状况受到了外界影响,因此需要重新对结构面组合块体稳定性进行评价。通过对金川水电站左岸引水发电系统进水口边坡的岩性、构造、变形失稳机制以及岩体质量和力学参数的研究,利用空间坐标建立了边坡和结构面的三维地质模型,结合边坡的开挖设计,进行平行和垂直轴向边坡方向的剖切,从而得到块体组合情况。然后,利用商用岩石边坡块体稳定性计算程序对各潜在不稳定块体进行计算。计算结果表明:除了在极端的工况下局部块体会失稳外,其它块体均较稳定。

New free surfaces are created in the excavated slope,and the initial stability of rock blocks suffers from the outside influence.Therefore,the stability evaluation needs to be enforced on the rock blocks bounded by structural surface.The lithology,structure,deformation and failure mechanism of the slope,the quality and mechanics parameters of rock mass are studied at the inlet of the diversion tunnel at the left bank of Jinchuan Hydropower Station.A three dimensions geologic model of the slope and structural surface is established by using space coordinates.Under the consideration of the excavated rock slope,the slices of the parallel and vertical axial side slope are carried on,thus,the block body combination situations are obtained.The stability of the potentially unstable blocks is calculated by using the business analysis software for the stability of rock slope wedges.The calculated results show that the slope is stable under various working conditions except for the extreme poor working condition.