珲春紫金曙光金铜矿露天矿边坡稳定性三维数值模拟

Three-dimensional Numerical Simulation of the Slope Stability of Hunchun Zijinshuguang Gold and Copper Open Pit Mine

为研究珲春紫金曙光金铜矿露天采场整体边坡的稳定性,通过3GSM结构面摄像测量、点荷载试验并采用Hoek-brown准则获取边坡岩体力学参数并对进行岩体质量分级,结合露天矿中长期采剥计划建立露天矿开采的三维模型,利用FLAC3D并基于弹塑性本构模型进行露天矿边坡三维数值模拟分析,结果表明①北帮边坡受断层构造及破碎带影响,岩体质量较差为IV级岩体,局部破碎区域为V级;②开挖至第6 a后,塑性区主要分布于北帮东侧边坡以及中部断层蚀变带区域;③开挖至最终境界,西北帮边坡深部的塑性区范围以及内部贯通程度明显增加,有较大的滑坡风险,应采取加固及疏干排水的防治措施。

In order to study the slope stability of the Hunchun Zijin Shuguang gold and copper open pit,the 3GSM structural plane photogrammetry and point load test are carried out.Then it takes the quality grading index for main rock basis,and uses Hoek-Brown to study mechanics parameters of the slope rock mass.The three-dimensional model of the open pit mining is established combining with the medium to long-term mining plan of open pit.An elastic-plastic constitutive model is used to calculate the slope stability based on FLAC 3D.The results of three-dimensional numerical simulation analysis show that:①The north slope stability is affected by fault structure and fracture zone,the quality of rock mass is class IV,and the local fracture zone is class V;②After excavation to the 6th year,the plastic zone is mainly distributed in the northeastern slope and fault alteration zone of the middle slope;③After excavation to the final boundary slope,the plastic zone in the deep part of the northwest slope is obviously increased in the size of area and the degree of penetration.Reinforcement and drainage measures should be taken for the safety of slope.