摘要
为了研究起爆时差对孔间裂纹扩展的影响,采用动态焦散线实验的方法,研究含缺陷介质相邻切槽炮孔被采用同时起爆和微差起爆时孔间爆生裂纹的扩展和贯通机制。研究结果表明:(1)在定向断裂控制爆破过程中,其他参数相同时,同时起爆的爆生裂纹成壁质量比微差起爆的质量好。因此,在岩体的定向开挖工程中,可采用同时起爆的方法来提高定向断裂控制爆破的效果。(2)爆炸应力波中的P波前缘压缩波与爆生运动裂纹相互作用降低了爆生运动裂纹的扩展速度和爆生裂纹尖端应力强度因子的值。实验研究结果对于定向断裂控制爆破工程实践具有一定的借鉴意义和参考价值。
In order to study the influence of delayed initiation on crack propagation between boreholes,the propagation and coalescence of blast induced cracks between two notched boreholes in PMMA with a pre-existing crack under the blasting load of simultaneous initiation and delayed initiation were studied using the dynamic caustics method. The results showed that the quality of blast induced walls of simultaneous initiation was better than that of delayed initiation in the directional fracture-controlled blasting when other parameters were the same. Consequently,in the excavation of rock,simultaneously initiation technology should be used to enhance the quality of directional fracture-controlled blasting. The propagation speed and the dynamic stress intensity factor were reduced due to the interaction between the compressive stress waves of P waves in explosive stress waves and the propagating cracks.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2015年第11期2293-2300,共8页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金面上项目(51374210)
国家自然科学基金重点项目(51134025)
中央高校基本科研业务费资助项目(2009QL15)
关键词
岩石力学
微差起爆
动态焦散线
切槽炮孔
爆生裂纹扩展
rock mechanics
delayed initiation
dynamic caustics
notched boreholes
blast induced crack propagation
