某露天铁矿采坑固结堆存协同挂帮矿安全高效开采研究

Study on Safe and Efficient Miningon Hanging Wall of Coordinating Cemented Storage in an Open-pit Iron Mine

为解决富余尾矿堆存难题,某铁矿南采坑露天开采结束后规划实施生态恢复,挂帮矿体采用地下开采,应用分段空场嗣后充填法。根据某铁矿南采坑的工程地质条件、挂帮矿开采和充填方案,构建了南采坑回填和地下开采的数值模型,分析计算模型的初始状态,模拟了挂帮矿体地下开采的过程。首先依据矿体的开采技术条件,通过采用数值模拟方法研究分析不同岩性下顶板的应力、应变、塑性区等情况评价采场的稳定性,优选合理的采场结构参数;此后模拟分析南采坑回填与不回填工况下对地下开采的影响,揭示了南采坑挂帮矿地下开采不同时期露天边坡、回填体的应力和塑性区的变化规律。通过对不同开采时期的应力和塑性区的综合对比分析后,建议在-60 m中段矿体开采时,应加强对露天边坡和井下采场、巷道的应力及位移的综合监测。

In order to solve the problem of surplus tailings stockpiling,ecological restoration is planned and implemented after the end of mining in the south of an iron mine.The hanging wall ore body is underground mining and application of sublevel open stopping with subsequent filling method.According to the engineering geological conditions of the south mining pit,the mining and filling scheme of the hanging wall mine,the dimensional numerical model of the south mining pit filling and underground mining is constructed to analyze the initial state of the computational model and simulate the filling process of the underground mining process of the hanging wall ore body.Firstly,according to the and mining technical conditions of ore body,stress,strain and plastic zone of roof under different lithology were studied and analyzed by numerical simulation method to evaluate the stability of stope and optimize the reasonable stops structural parameters.Finally,the influence of underground mining from backfill and no backfill in the south mining pit is simulated and analyzed.also,the stress and plastic zone changes of the open-pit slope and filling body in the hanging wall mine at different periods of underground mining are revealed.Through the comprehensive comparative analysis of the stress and plastic zone in different mining periods,it is suggested to strengthen the comprehensive monitoring of the stress and displacement of the open-pit slope,underground stope and roadway during the mining of the ore body in the-60 m section.