摘要
针对地下矿山扇形中深孔爆破大块率高、施工作业效率低的问题,通过研究组间延时时间对岩石破碎效果的影响机制,提出降低大块率的爆破优化方法。建立了基于岩石损伤效应的破碎效果评价标准,优化了扇形孔分组爆破技术;通过数值模拟分析了不同组间延时时间下的岩石损伤演化规律、应力波传播特性及有效应力变化趋势;提出了基于岩石破碎度阈值的残余体积评价指标、定量关联体积残余率与大块率参数,确定3 ms为最优组间延时时间。现场试验表明:在孔径90 mm、炸药单耗0.46 kg/m^(3)条件下,采用3 ms组间延时爆破,使大块率从9.3%降至6.2%,破碎效果显著优于无延时爆破设计。分组延时爆破技术通过调控应力波叠加效应增强岩石损伤,验证了残余体积评价指标的科学性,为地下矿山扇形孔爆破大块率控制提供了有效方法。
Aiming at the issues of a high large-block rate and low construction operation efficiency in deep-hole blasting within underground mining sectors,this study investigates the influence mechanism of inter-group delay time on rock fragmenta-tion effects.A blasting optimization method to reduce the large-block rate is proposed.An evaluation standard for rock fragmen-tation based on the damage effect is established,and the fan-shaped hole group blasting technology is further optimized.Through numerical simulation,the evolution law of rock damage,the propagation characteristics of stress waves,and the varia-tion trend of effective stress under different inter-group delay times are analyzed.A residual volume evaluation index based on the rock fragmentation threshold is introduced.The parameters of volume residual rate and large-block rate are quantitatively correlated,and 3 ms is determined as the optimal inter-group delay time.Field tests demonstrate that,under conditions of a hole diameter of 90 mm and a single explosive consumption of 0.46 kg/m3,the application of 3 ms inter-group delayed blasting re-duces the large-block rate from 9.3%to 6.2%,achieving significantly better fragmentation performance compared to designs without delayed blasting.The group-delayed blasting technology enhances rock damage by regulating the superimposed effect of stress waves,verifies the scientific validity of the residual volume evaluation index,and provides an effective method for control-ling the large-block rate in fan-shaped hole blasting within underground mines.
作者
张启隆
徐振洋
王雪松
张祚富
刘奥博
ZHANG Qilong;XU Zhenyang;WANG Xuesong;ZHANG Zuofu;LIU Aaobo(School of Mining Engineering,University of Science and Technology Liaoning,Anshan 114000,China;Liaoning Province Green Mining Engineering Research Center for Metal Mineral Resources,Anshan 114000,China)
出处
《金属矿山》
北大核心
2025年第7期114-123,共10页
Metal Mine
基金
辽宁省“兴辽英才计划”项目(编号:XLYC2203173)
矿山智能爆破与创新技术平台建设项目(编号:LJ232410146045)。
关键词
地下矿山
扇形孔
爆炸载荷
数值模拟
underground mine
fan-shaped hole
explosive load
numerical simulation
