某铁矿露天采坑尾矿胶结充填边坡稳定性分析

Stability Analysis of Tailings Cemented Filling Slope of an Iron Ore Open Pit

针对某铁矿生产实际,尾矿库经过多年的放矿运行,存在库容不足、富余尾矿的堆存等问题,经过前期大量调研,提出南露天采坑闭坑后实施生态恢复的方案,采用露天采坑胶结堆存尾矿。采用数值模拟软件对某铁矿南露天坑尾砂充填后南北坑间岩墙稳定性进行了分析,分别考虑了地下水、地震等荷载条件以及南坑不同堆排时期、护坡层厚度等因素对南北坑间岩墙稳定性的影响。结果表明:护坡层厚度对岩墙边坡稳定性基本无影响;随着尾砂胶结堆存高度的增加南北坑间岩墙边坡安全系数基本保持恒定。通过南坑尾砂堆存后地下水+地震荷载作用下岩墙边坡稳定性分析,表明在该地区地震设防烈度条件下岩墙边坡安全系数符合设计规范要求。

According to the actual production of an iron mine,after years of ore drawing operation,the storage capacity of the tailings storage facility is insufficient,and the problem of the stockpiling of surplus tailings needs to be solved.After a lot of research in the early stage,the scheme of ecological restoration is proposed to be implemented after the closure of the south open pit,and the cementation storage of tailings in the open pit is adopted.Numerical simulation sofware is used to analyze the stability of rock walls between the north and south pits after flling of tailings in the south open pit of the iron mine.The effects of groundwater,seismic and other loading conditions,as well as the different stockpiling and discarding periods of the south pit and the thickness of the slope protection layer on the stability of the rock wall between the north and south pits are considered respectively.The results show that the thickness of slope protection layer has basically no effect on the stability of rock wall slope.With the increase of the height of cementation stockpiled tailings,the safety factor of the rock wall slope between the north and south pits basically keeps constant.Through the stability analysis of rock wall slope under the action of groundwater and seismic load after stockpile of tailings in the south pit,it shows that the safety factor of rock wall slope meets the requirements of the design code under the condition of seismic intensity in the area.