【摘要】 为解决深部金属矿山高地应力引发的围岩失稳问题，以某矽卡岩型铁矿-450～-540 m中段为工程背景，针对分段空场嗣后充填法存在的采场参数不合理、开采稳定性差等问题，开展矿房跨度优化研究。采用尖点突变理论构建顶板固支梁力学模型，计算得出顶板理论极限跨度为17.24 m，据此初选12,15,18 m共3组跨度方案；依托FLAC^3D开展数值模拟，基于Hoek-Brown方程折算岩体参数，采用摩尔-库仑准则对比分析围岩稳定性。结果表明：矿房跨度与顶板沉降、拉应力呈非线性正相关；12,15 m跨度顶板沉降量分别为29.00,36.68 mm，稳定性良好；18 m跨度沉降达52.30 mm，塑性区面积较12 m跨度扩大115%，围岩呈渐进式破坏。综合安全与生产效率，确定最优矿房跨度为15 m。该研究形成的理论结合数值模拟优化方法，可为同类深部矿山采场结构设计及围岩管控提供参考。更多还原

【Abstract】 To solve the surrounding rock instability induced by high in-situ stress in deep metal mines,taking the-450～-540 m sublevel of a skarn-type iron mine as the engineering background,an optimization study on ore chamber span is conducted targeting the problems of unreasonable stope parameters and poor mining stability existing in the sublevel open stoping with backfilling method. A fixed-beam mechanical model of the roof is established by the cusp catastrophe theory,and the theoretical ultimate span of the roof is calculated to be 17.24 m,based on which three preliminary span schemes of 12 m,15 m and18 m are selected. Numerical simulation is carried out with FLAC^3D,rock mass parameters are converted based on the Hoek-Brown criterion,and the Mohr-Coulomb criterion is adopted to compare and analyze the surrounding rock stability. The results show that the ore chamber span presents a non-linear positive correlation with roof subsidence and tensile stress. The roof subsidence of 12 m and 15 m spans is 29.00 mm and 36.68 mm respectively,with good stability. The subsidence of 18 m span reaches 52.30 mm,and the plastic zone area is 115% larger than that of 12 m span,indicating progressive failure of surrounding rock.Considering both safety and production efficiency,the optimal ore chamber span is determined as 15 m.The research method integrating theoretical analysis with numerical simulation can provide reference for stope structure design and surrounding rock control in similar deep mines.更多还原