摘要
为了研究装药结构对切缝药包爆破效果的影响,采用新型数字激光动态焦散线测试系统和数值模拟相结合的方法,对比分析了切缝管内耦合装药与不耦合装药方式下切缝药包的冲击动力学行为和爆生裂纹的动态力学行为。研究结果表明:切缝药包定向爆破效果显著,爆生主裂纹的扩展形式以拉伸断裂模式为主,爆生气体的楔入作用是裂纹持续扩展的重要驱动力;切缝管和透射压力波均对孔壁造成冲击破坏,在炮孔周边产生与切缝方向成一定角度的"X"交叉型次裂纹和微小的密集裂隙区,耦合装药比不耦合装药所成角度更大,裂隙数量更多;采用不耦合装药结构爆破时,爆生主裂纹的扩展距离更长,扩展速度和动态应力强度因子更大;数值模拟结果显示,不耦合装药结构使得爆轰波对炮孔壁的冲击作用降低,爆生气体的准静态作用加强。与耦合装药相比,能够增大试件在切缝方向的应力集中程度,提高爆生主裂纹的断裂力学参数。
A new testing system of digital laser dynamic caustics,combined with a numerical simulation analysis,was adopted to comparatively analyze the impact dynamic behaviors of slotted cartridges and the dynamic mechanical behaviors of explosive cracks when the coupling charge and uncoupled charge fitted in slotted pipe interior were used. The results show that slotted cartridges can realize obvious directional fracture-controlled blasting,the propagation form of explosive main crack is dominated by the tensile fracture mode,and the wedge effect of explosive gas is an important driving force for the continuous expansion of crack. There are four minor cracks presented in a ＂x＂cross shape with a certain angle to the slot direction and a tiny dense fissure area around borehole because of the impact effect of slotted pipe and transmitted pressure wave on borehole wall,and a greater angle and more fissures will be presented on coupling charge structures than on uncoupled charge structures. For uncoupled charge structures,the propagation distance of explosive main crack is longer,and the crack expansion velocity and dynamic stress intensity factor are larger. The numerical simulation results indicate that uncoupled charge structures reduce the impact effect of detonation wave on borehole wall and strengthen the quasi static effect of explosive gas. Compared with coupling charge structures uncoupled charge structures can increase the stress concentration of the specimen in slot direction and improve the fracture mechanics parameters of the main explosive crack.
作者
岳中文
张士春
邱鹏
李站飞
原凯
YUE Zhongwen;ZHANG Shichun;QIU Peng;LI Zhanfei;YUAN Kai(School of Mechanics ＆ Civil Engineering, China University of Mining ＆ Technology （Beijing）, Beijing 100083, China)
出处
《振动与冲击》
EI
CSCD
北大核心
2018年第10期27-34,共8页
Journal of Vibration and Shock
基金
国家自然科学基金面上资助项目(51374210)
爆炸科学与技术国家重点实验室(北京理工大学)开放基金(KFJJ17-01M)
关键词
切缝药包
装药结构
动态焦散线
数值模拟
裂纹扩展
slotted cartridge
charge structure
dynamic caustics
numerical simulation
crack propagation
