缓倾斜极厚矿体高阶段采场开采顺序优化

Optimization of Mining Sequence for High-Level Stope with Gently-Dipping and Extra-thick Orebody

为了平衡缓倾斜极厚矿体高阶段采场的产能与安全,以某铁矿阶段空场嗣后充填采矿法为背景,进行开采顺序优化研究。首先,基于间柱承压理论,得出间柱宽度合理值为14.2~47.2 m。根据采场结构参数,设计间柱宽度分别为15 m、30 m、45 m,即隔一采一、隔二采一、隔三采一,并采用FLAC^(3D)建立矿体模型,对比分析各方案顶板沉降以及间柱稳定性。最后,在数值模拟基础上,综合考虑安全与产能的影响因素,构建基于层次分析与模糊综合评判法的开采顺序判断矩阵,计算得出3种方案的综合隶属度分别为0.86、0.79、0.80,确定间柱宽度15 m(隔一采一)为最优方案。工业试验结果表明,该方案在实现最大化生产能力的同时,可保持采场相对稳定。

In order to balance productivity against safety in the mining of high-level stope with gently-dipping and extra-thick orebody,an iron mine adopting sublevel open stoping with backfill was taken as an example to optimize the mining sequence.Firstly,pillars was determined to at a reasonable spacing from 14.2 m to 47.2 m based on the theory of bearing capacity of pillars.Secondly,according to stope structure parameters,the pillars were designed to be 15 m,30 m and 45 m in thickness,respectively.An orebody model was also established with FLAC^(3D) and then was used to analyze the roof subsidence and pillar stability based on comparison of each mining scheme.Finally,a judgment matrix of mining sequence was constructed based on analytic hierarchy process and fuzzy comprehensive evaluation method,with both factors of safety and productivity taken into consideration in the numerical simulation.The comprehensive membership degrees of those three schemes were calculated to be 0.86,0.79 and 0.80,respectively,and pillars in the best scheme were determined to be in the thickness of 15 m.The results of an industrial experiment have proven that this scheme can ensure stope with relative stability while achieving the maximum production capacity.