为了评价松树南沟矿区边坡岩体开挖稳定性情况,指导矿山的安全施工,以结构面测量与工程勘察为基础,分析边坡岩体结构面的分布及岩体结构特征,得到对边坡稳定起控制作用的优势结构面.利用结构面三维网络模拟技术,对上述优势结构面进行计算机模拟,建立结构面网络模型,再现岩体结构.分别沿平行和垂直各测线走向方向切割网络模型,发现岩体部分区域被结构面切割严重,为形成小规模的可动块体提供了有利条件.运用分形理论计算了各切面的分形维数,计算得出边坡岩体处于一般或差的状态;借助有限差分软件FLAG3D,计算开挖后边坡岩体的稳定性情况,结果表明:由于开挖卸荷局部边坡台阶处出现了较大的位移和塑性区,可能出现崩塌、滑移破坏,与质量评价结果一致,建议适当放缓该区域台阶坡面角.
In order to evaluate the stability of slope rock mass after excavation and to guide construction safety,based on the discontinuity measurement and engineering survey,the characteristics of discontinuity distribution and rock mass' structure in Songshunangou Mining Area were analyzed,thus obtaining the advantage discontinuity which controls the slope stability.Three-dimensional network simulation technology was used to make simulation on the advantage discontinuity above and establish the network model to represent the rock-mass's structure.The network model was cut along each measuring line in parallel or perpendicular direction.It is found that rock-mass were cut seriously by the discontinuity,which provides favorable conditions for the formation of small-scale movable ore blocks.The fmctal dimension of each section was calculated by the fractal geometry theory,finding that rock mass is in general or poor state.With the aid of the finite difference software FLAC3D,the stability of rock mass after excavation was calculated.The results showed that due to the excavation and unloading,larger displacement and plastic zone in some parts of slope were generated,possibly resulting in collapse and slippage.It fits with the quality assessment,so reasonably lowering the step slope angle is recommended.