露天矿节理岩质边坡稳定性分析

针对弓长岭露天铁矿东帮节理岩体边坡的结构特征,使用3GSM三维岩体不接触测量系统,进行了结构面调查及统计分析,获取了结构面倾向、结构面倾角以及节理迹长、节理间距的详细统计数据。基于Monte-Carlo随机模拟方法,使用结构面网络模拟的软件Frac Sim3D,得到节理岩体的三维网络模型。在建立的三维网络模型基础上,采用钻孔取样方法获取节理岩体的岩体质量指标RQD,结合现场点荷载强度试验,进而获取RMR指标,基于Hoek-Brown经验方法得到节理岩体的抗剪强度参数。通过FISH语言编程实现了对复杂节理岩体的精细建模,采用离散元软件UDEC对边坡进行稳定性分析。结果表明:边坡整体处于稳定状态,局部发生岩体变形,受顺倾结构面控制,边坡顶部岩体沿结构面产生楔体破坏,局部散体区域出现掉块现象。

Stability analysis for jointed rock slope in an open iron ore mine

According to the structure characteristics of the joint rock mass of the east slope of Gongchangling open iron ore mine,using the 3 dimensional rock non-contact measurement system (3GSM),the investigation and statistical analysis of surface structure are performed.Detailed statistics data including surface structure tendency,inclination,joint trace length,and joints pitch are obtained.Based on Monte-Carlo stochastic simulation method,the three-dimensional network model of jointed rock mass is obtained by the structural network simulation software FracSim3D.The rock quality index RQD is obtained by drilling samples on the three-dimensional network model.Then the RMR index is evaluated combined with on-site point load test.The shear strength parameters of jointed rock mass are obtained by Hoek-Brown method.Jointed rock slope is modeled through the FISH language programming,and the stability of the slope using the discrete element software UDEC is performed.The results show that the slope is in a stable state,but the local wedge failure of rock mass occur in the upper areas of slope,which is controlled by the joints along slope direction.The phenomenon of block out also appears in dispersion zone.