共轭节理间距及地应力对煤体爆破裂纹分布规律影响的研究  

Study on Influence of Conjugate Joint Spacing and In-situ Stress on Distribution Law of Coal Blasting Cracks

作　　者：张强[1] 张传伟 ZHANG Qiang;ZHANG Chuanwei(Heidaigou Open-pit Mine,Guoneng Zhunneng Co.,Ltd.,Ordos 010300,China;School of Mining Engineering,China University of Mining and Technology,Xuzhou 221116,China)

机构地区：[1]国能准能集团黑岱沟露天煤矿,内蒙古鄂尔多斯010300 [2]中国矿业大学矿业工程学院,江苏徐州221116

出　　处：《煤炭技术》2022年第5期152-155,共4页Coal Technology

摘　　要：煤体地应力、节理对岩体爆破裂隙扩展规律起着控制作用。采用理论与数值模拟结合的方法,研究共轭节理间距及地应力侧压系数对煤体爆破裂隙扩展规律的影响。首先根据岩石断裂力学最大能量释放率准则研究了含节理煤体爆破裂纹扩展机制,然后采用数值模拟研究了分别为无节理、节理间距依次为0.2、0.3、0.4 m,和侧压系数分别为0.5、0.75、1、1.5时对爆破裂纹扩展的影响。计算结果表明:(1)受节理影响,在爆破载荷的作用下,在节理面位置发育的爆破裂纹数量占比较大,爆破裂纹随着节理间距由0.2 m增加至0.4 m,节理对爆破裂纹的发育程度影响先增大后减小;(2)地应力可以明显地控制煤体爆破裂纹的产状,使得爆破裂纹优先沿着地应力大的方向扩展,且在节理处生成的爆破裂纹较非节理处爆破裂纹较易发生扩展。研究结果可为煤体爆破增透爆破参数设计提供一定的借鉴意义。The in-situ stress and joint of coal body control the crack propagation law of rock mass blasting.The effects of conjugate joint spacing and in-situ stress lateral pressure coefficient on the crack propagation law of coal blasting are studied by combining theory and numerical simulation.Firstly,the blasting crack propagation mechanism of jointed coal is studied according to the maximum energy release rate criterion of rock fracture mechanics,and then the effects of no joint,joint spacing of 0.2,0.3 and 0.4 m,and lateral pressure coefficient of 0.5,0.75,1 and 1.5 on blasting crack propagation are studied by numerical simulation.The calculation results show that:(1)Under the influence of joints,the number of blasting cracks developed at the joint surface accounts for a large proportion under the action of blasting load.With the increase of joint spacing from 0.2 m to 0.4 m,the influence of joints on the development of blasting cracks first increases and then decreases;(2)Under the inhibition of insitu stress,cracks not on the joint surface are more likely to be restrained under the action of blasting load.At the same time,with the change of in-situ stress lateral pressure coefficient,the development degree of blasting cracks on the joint surface is greater on the side with large in-situ stress.The research results can provide a certain reference for the design of permeability increasing blasting parameters of coal blasting.

关 键 词：爆破裂纹 地应力 煤体 共轭节理 

分 类 号：TD712[矿业工程—矿井通风与安全]