扇形孔爆破落矿大块产生机理及控制研究  

Production Mechanism and Control Measure of Boulder by Fan Shaped Round Blasting

作　　者：王平[1,2] 李斌[1,2] 许梦国[1,2] 

机构地区：[1]武汉科技大学资源与环境工程学院,武汉430081 [2]冶金矿产资源高效利用与造块湖北省重点实验室,武汉430081

出　　处：《爆破》2015年第2期1-10,58,共11页Blasting

基　　金：国家自然科学基金资助项目(编号50804036);武汉市晨光计划资助项目(编号201050231045);湖北省教育厅重点项目(D20111107)

摘　　要：针对程潮铁矿无底柱分段崩落法井下扇形孔爆破落矿大块率偏高影响安全生产的现状,利用现场调研数据进行大块产生机理分析,得出大块分布规律,指出孔底距偏大是导致大块率偏高的主要原因,并针对性地提出2种扇形孔改进方案。通过相似模拟试验研究分析得出改进后的方案大块率大幅度降低,并指出大块率随着排距的降低而减小。通过数值模拟研究得出爆破应力波在相邻炮孔间的叠加效果,提出存在某种合理的范围,当相邻炮孔爆破应力波在这范围内相互叠加或碰撞时,应力可以得到几何倍数的增加;而小于这个范围时爆破应力却出现降低的情况;当超出这个范围时,应力波的叠加或碰撞程度表现得很低。在现场实施改进后的扇形孔布孔方案后,大块率得到显著的降低。Aiming at current situation of high boulder yield which has already influenced safety production in the mining with non-pillar sublevel caving fan shaped round blasting in Chenchao iron mine, the mechanism of boulder production was analyzed based on the on-site data, and the distribution of boulder was obtained and the slightly larger hole-bottom spacing is the main reason caused high bolder yield. Then two improvement schemes of fan shaped bore- hole were put forward. Though simulation experiment, the improved schemes decreased greatly boulder yield when distance between two rows reduced. The superposition effect of explosion stress wave was researched through numeri- cal simulation, and it exists a reasonable range. The blasting pressure increases in geometrically multiplied rate when borehole space is in this range. Whereas it presents decreased when the space is under the range, and the superposi- tion effect becomes inconspicuous when the space exceeds the range. The boulder yield decreased significantly when the improvement schemes were implemented on-site.

关 键 词：无底柱分段崩落法 扇形孔 大块率 孔底距 

分 类 号：TD235.3[矿业工程—矿井建设]