利用爆炸加载数字激光动态焦散线试验系统,对不同装药结构爆破爆生裂纹动态断裂效应进行分析,研究切缝药包的定向断裂控制爆破机制,比较爆生主裂纹和次裂纹动态能量释放率的差异。结果表明:不耦合系数1=1.67时,切缝药包爆破效果最理想;爆生主裂纹的扩展速度、动态应力强度因子随时间总体呈振荡下降的趋势,在扩展过程的中后期达到一个较小的峰值;橡皮泥介质作为炸药爆炸产物与炮孔壁间的缓冲层,传能效果良好;次裂纹尖端的动态能量释放率数值整体上小于2条主裂纹。
Explosion load test system of digital laser dynamic caustics is used to analyze the dynamic fracture effect of blasting crack with different charging structures. Mechanism of directional fracture blasting with slotted cartridge is studied and the difference of dynamic energy release rate between principal crack and secondary crack is compared. The results show that the blasting effect is best when the decoupling coefficient al = 1.67. The propagation velocity and dynamic stress intensity factor of principal crack show a downward trend in the mass, and is up to a smaller peak in the midand late-expansion processes. As the buffer layer between explosive product and blasting hole wall, the plasticine medium transfers energy well. The dynamic energy release rate values of secondary crack as a whole is less than that of two principal cracks.