基于数值模拟的露天转地下开采关键参数优化研究

Research on Optimization of Key Parameters of Open-pit to Underground Mining Based on Numerical Simulation

基于某露天铁矿转入地下开采时矿体上下盘围岩需要被保护的特殊情况,结合深部矿体赋存特征,采用FLAC^(3D)对地下回采关键参数进行数值模拟分析。研究发现,地下开采矿体内上盘回采单元采场顶部与上盘边界之间预留的矿柱水平宽度对采场空区及上盘围岩稳定性有较大影响。为实现深部资源高效安全开采,推荐上盘回采单元采场顶部预留的矿柱水平安全宽度为10 m,并采用盘区间隔回采的顺序,开采完成应尽快进行充填作业,以控制采场顶板沉降。

Based on the special situation that the surrounding rock of the upper and lower plates of the ore body needs to be protected when an open-pit iron mine is transferred to underground mining,combined with the occurrence characteristics of deep ore bodies,the key parameters of underground mining are ana⁃lyzed by numerical simulation using FLAC^(3D).It is found that the horizontal width of the pillar reserved be⁃tween the top of the stope and the boundary of the hanging wall in the upper mining unit of the underground mining orebody has a great influence on the stability of the stope goaf and the surrounding rock of the hang⁃ing wall.In order to realize the efficient and safe mining of deep resources,it is recommended that the hori⁃zontal safety width of the pillar reserved at the top of the stope of the hanging wall mining unit is 10 m,and the sequence of interval mining between plates is adopted.Filling operation should be carried out as soon as possible to control the roof settlement of the stope.