深凹露天矿转地下过渡期挂帮矿安全高效开采方法研究

露天矿在回采末期由露天转向地下开采过程中通常会面临减产过渡的问题,矿山一般会在此期间回采挂帮矿以补充产能,传统的挂帮矿回采方法存在安全性差、效率低及产能低等一系列问题,难以从根本上扭转减产过渡的困境。以某深凹露天矿转地下开采为工程背景,在综合分析挂帮矿分布位置、开采条件及矿岩特性的基础上,提出在过渡期利用诱导冒落法率先回采该矿南帮挂帮矿的技术方案,通过控制回采顺序诱导失稳边坡滑向采空区而不冲至露天坑底,以确保坑底露天采矿的安全性,从而在过渡期实现露天与地下安全高效协同开采,达到稳产甚至增产的建设目标。最后,利用数值模拟方法对南帮挂帮矿的诱导冒落回采方案进行了数值模拟研究,研究结果表明,在深凹露天矿条件下利用诱导冒落法回采挂帮矿是安全可行的。

Study on safe and efficient mining method of deep open pit mine during the transition from open pit to underground mining

During the transition from open pit to underground mining, mines are usually faced with the problem of reducing production. Generally, mines will be mining hanging-wall ore-body to supplement production capacity during this period. Traditional mining methods for hanging-wall ore-body have a series of problems such as poor safety, low efficiency and low production capacity, which make it difficult to fundamentally reverse the dilemma of reducing transition. With a deep open pit transition into underground mining as an engineering background, on the basis of comprehensive analysis for hanging-wall ore-body distribution location, mining conditions and the ore-rock characteristics, the technology scheme of mining hanging-wall ore-body in south slope by induced caving method was proposed in transition period. In order to ensure the safety of open-pit mining, the unstable slope is induced to slide towards the goaf rather than to the open pit floor by controlling the mining sequence, so as to realize the open pit and underground safe and efficient cooperative mining in the transitional period. Finally, the numerical simulation method is used to study the induced caving mining scheme of hanging-wall ore-body in south slope. The results show that it is safe and feasible to use the induced caving method to mining hanging-wall ore-body under the condition of deep open-pit mine.