地应力效应下某矿中深孔爆破参数优化研究  

Optimization Research on Blasting Parameters for Medium-Deep Holes in a Mine Under the Effect of In-Situ Stress

作　　者：陈帮洪 粟登峰 陈星明[1] 李正国 梁博 CHEN Banghong;SU Dengfeng;CHEN Xingming;LI Zhengguo;LIANG Bo(School of Environment and Resource,Southwest University of Science and Technology,Mianyang,Sichuan 621010,China)

机构地区：[1]西南科技大学环境与资源学院,四川绵阳市621010

出　　处：《矿业研究与开发》2023年第4期42-49,共8页Mining Research and Development

基　　金：国家自然科学基金项目(519042048);四川省自然科学基金项目青年科学基金项目(2022NSFSC1089);西南科技大学博士基金项目(18zx7124)。

摘　　要：合理的爆破参数是取得良好爆破效果的保证,是实现无底柱分段崩落法安全、高效开采的前提与基础。针对目前无底柱分段崩落法首采进路的首排炮孔中深孔爆破参数设计均未考虑地应力的影响,进而造成爆破块度分布不均匀以及眉线破坏的问题,以扇形炮孔中间的3个特征炮孔为研究对象,首先分析了无底柱分段崩落法开采过程中的围岩应力变化情况,随后利用ANSYS/LS-DYNA模拟了不同围岩地应力条件下的岩石爆破效果,结果表明:随着水平构造应力增加,扇形炮孔之间的矿岩爆破有效应力减小,而自由面附近的矿岩爆破有效应力逐渐增加。无地应力荷载下的孔底距取值为2.2~2.4 m,最小抵抗线取值为1.5 m,当地应力荷载逐渐增大到原岩构造应力时,此时孔底距取值为2.2~2.3 m,最小抵抗线可以取到1.5~1.8 m。在此基础上,对首采进路/首排炮孔爆破参数进行优化,并在某矿山1580中段23#进路前几排炮孔进行了现场应用,结果表明,崩落矿体爆堆集中,崩落矿石块度较均匀,眉线破坏情况得到改善。研究结果可为类似矿山中深孔爆破参数优化提供参考依据。Reasonable blasting parameters are the guarantee of good blasting effect,and are the premise and foundation for achieving safe and efficient mining by non-pillar sublevel caving method.The blasting parameters of the first row of deep holes in the first mining drift of the non-pillar sublevel caving method do not take into account the influence of ground stress,which causes uneven distribution of blasting block and brow line damage.To address this problem,the middle three feature holes among fan-shaped holes were taken as the research objects,the stress variation of surrounding rock during the mining process of non-pillar sublevel caving method was analyzed firstly,and then the rock blasting effects under different in-situ stress conditions of surrounding rock were simulated using ANSYS/LS-DYNA.The results show that the effective blasting stress between the fan-shaped holes decreases as the horizontal tectonic stress increases,while the effective blasting stress near the free surface gradually increases.Under non geostress loading,the hole bottom distance is taken as 2.2-2.4 m,and the minimum resistance line is taken as 1.5 m.When the geostress load gradually increases to the tectonic stress of the original rock,the hole bottom distance is taken as 2.2-2.3 m,and the minimum resistance line can be taken as 1.5-1.8 m.On this basis,the blasting parameters of the first mining drift/first row of blast holes were optimized and applied in the first few rows of blast holes of the 23#drift in the 1580 middle of mine.The results show that the collapsed ore bodies are concentrated in blasting piles,the sizes of the collapsed ore are relatively uniform,and the brow line damage has been improved.The research results can provide reference for the optimization of medium and deep hole blasting parameters in similar mines.

关 键 词：无底柱分段崩落法 ANSYS/LS-DYNA 地应力 扇形中深孔爆破 参数优化 

分 类 号：TD235.33[矿业工程—矿井建设]