采场结构参数是软弱破碎矿体开采的关键问题,对采矿各指标起着决定性作用,不合理的结构参数可能造成灾难性安全事故。以汤丹铜矿4#软弱破碎厚大矿体为研究对象,采用岩体分类统计、工程类比、理论计算、数值模拟等手段对顶柱、矿房及矿柱进行参数优化,并对比各研究方法的优劣。研究表明:汤丹铜矿4#矿体围岩岩体质量为Ⅲ级,矿体为Ⅳ级,矿房最大暴露面积为300 m^2;理论计算结果表明:矿房极限跨度是顶板厚度或矿柱宽度的单因素函数,且呈线性正比关系,矿房跨度为10-14 m,矿柱为14-18 m,顶柱为18-25 m,但各理论计算结果差别较大;应用ANSYS与FLAC3D对矿体开挖进行三维数值模拟,从地表岩移、顶板位移、塑性区分布及矿柱最大主应力四个角度进行全面分析,最终得出顶柱高25 m,矿柱宽16 m,矿房跨度12 m为最优结构参数的结论。
Optimization of stope structure parameters is critical for weak-broken orebody mining which plays a crucial role in mining index.Incorrect structure parameters can cause catastrophic security incidents.Taking 4#orebody of Tangdan Mine as the research object,we optimize the parameters of top pillar,room,and pillar on the basis of rock classification statistical method,project analogy,theoretical calculations and numerical simulation.The advantages and disadvantages of each method were compared.The results show that the surrounding rock quality grade of 4# orebody of Tangdan Mine is Ⅲ,the orebody quality grade is Ⅳ,and the maximum permit exposure area is 300 m^2; on the basis of theoretical calculations the maximal room span is a single-factor function of thickness of top plate or width of pillar,and has a linear relation; the span of room is 10 -14 m,the width of pillar is 14-18 m,the height of top pillar is 18-25 m,and the difference between these methods is relatively greater; orthogonal design and three dimensional numerical simulation of mining process using ANSYS and FLAC3 Dwas carried out to analysis the surface rock mass movement,displacement of roof,plastic areas distribution,and maximum principal stress of pillars.Taking into account all these factor,we may safely draw the conclusion that the thickness of roof(pillar) is 25 m,the width of pillar is 16 m,and the width of room is 12 m.