柱状药包侧向爆破下抵抗线对岩石破碎特性的影响研究  

Effects of burden on rock crushing characteristics under lateral detonation of cylindrical charges

作　　者：李萍丰 王秀龙 闫小兵 马正腾 彭建宇[2] 张凤鹏[2] LI Ping-feng;WANG Xiu-long;YAN Xiao-bing;MA Zheng-teng;PENG Jian-yu;ZHANG Feng-peng(Hunan Lianshao Construction Engineering(Group)Co.,Ltd.,Changsha,Hunan 410001,China;Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines,Northeastern University,Shenyang,Liaoning 110819,China)

机构地区：[1]湖南涟邵建设工程(集团)有限责任公司,湖南长沙410001 [2]东北大学深部金属矿山安全开采教育部重点实验室,辽宁沈阳110819

出　　处：《岩土力学》2024年第5期1388-1396,共9页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.52274114)。

摘　　要：为研究抵抗线对柱状药包侧向爆破下岩石破碎特性的影响,采用波动理论,分析了自由面处的应力状态;采用直铜丝电爆炸模拟柱状药包爆破,开展了侧向爆破破岩的物理模型试验;再借助超高速摄像技术,观测了试件表面裂纹网的演化过程;结合爆破漏斗区形态、尺寸和碎块分布特征,研究了不同抵抗线下柱状药包爆破破岩特性。结果表明,抵抗线是控制岩石爆破破裂模式、破坏区形态和碎块块度大小的重要因素。随抵抗线增加,裂纹发育速度与密度减小,裂纹网覆盖范围增加,优先贯穿裂纹由横向转变为环向裂纹。此外,模型试验结果表明,破裂区短轴随抵抗线增加而增加。结合自由面处应力状态,利用最大拉应变准则对此进行了解释。建立了碎块块度与能量单耗之间的关系,研究成果为岩石工程爆破设计优化提供参考。To investigate the effects of burden on rock crushing characteristics under lateral detonation of cylindrical charges,we analyzed the stress state at the free surface using the wave theory.Afterward,to simulate the cylindrical charge detonation,the physical experiment of lateral rock fragmentation was conducted using direct copper wire electro-explosion.The evolution process of surface crack network of the specimen was observed using ultra-high-speed camera technology.The impact of cylindrical charge detonation on rock properties was studied by combining the morphology,dimensions,and distribution characteristics of the blasting crater with different burdens.The results demonstrated that the burden is a crucial factor for controlling the fracture mode,morphology of failure zone,and fragment size during rock blasting.As the burden increased,the crack propagation velocity and density gradually decreased,while the range of crack network expanded,and the preferential propagation direction of cracks changed from transverse to circumferential.Furthermore,the experimental results indicated an increasing trend in the short axis of the fracture zone as the burden increased.Through analyzing the stress state at the free surface,the maximum tensile strain criterion was applied to justify this phenomenon.Finally,the relationship between fragment size and energy consumption was established.Our research findings provide a reference for optimizing the design of rock engineering blasting.

关 键 词：柱状药包 抵抗线 破裂模式 破坏区形态 块度 

分 类 号：TD235[矿业工程—矿井建设]