基于多方法联合的露天转地下境界矿柱厚度优化

Multi-method Based Optimization of Crown Pillar Thickness from Open Pit to Underground

以山东黄金集团归来庄金矿露天转地下工程为依托,基于理论计算、比例跨度法和相似条件类比法等多种方法进行联合分析,确定归来庄金矿露天转地下境界矿柱的最优厚度范围为6~15 m.基于FLAC3D,计算不同厚度境界矿柱条件下,地下开采对境界矿柱和边坡稳定性的影响.结果表明,当境界矿柱厚度小于10 m时,地下开挖导致顶板变形量较大,且境界矿柱厚度越小,位移增量越大;当境界矿柱厚度大于10 m时,地下开挖导致的顶板变形较小且趋于平稳,10 m为境界矿柱厚度的最优值.

Taking a project from open pit to underground mining in the Guilaizhuang Gold Mine of Shandong Gold Group Co.,Ltd. as an example,multiple methods including theoretical calculation,scaled span approach and analogy under similar conditions are employed to analyse the rational scope of crown pillar thickness. The influence of underground mining on the crown pillar and slope stability is analysed with different thickness crowns using the software FLAC3 D.The calculation results show that the 10 m thick crown pillar can be viewed as a turning point：when the thickness is less than 10 m,the roof deformation caused by underground mining is large,and the thinner the crown pillar,the larger the displacement increment; when the thickness is over10 m,the roof deformation from underground mining is relatively small and tends to remain stable.