切槽孔爆破动态力学特征的动焦散线实验

应用爆炸加载的透射式动焦散线测试系统，分析了有机玻璃切槽孔爆破模型的裂纹动态特征变化规律。比较了不同切槽角度、切槽深度的定向断裂裂纹尖端的扩展长度、扩展速度和动态应力强度因子。初步探讨了切槽爆破的动态效应，研究表明切槽孔爆破早期裂纹破坏模式为爆炸拉应力波作用下的I型快速扩展裂纹，裂纹尖端拉应力集中积聚的较大应变能维持了爆炸裂纹进一步扩展，裂纹尖端扩展后期表现为P波、S波共同作用下的复合型扩展特征。切槽角为60时获得的定向断裂效果最好，合理切槽深度为炮孔半径的1/4～1/2。

Experimental investigation on dynamic mechanical behaviors of cracks induced by V-notch borehole blasting with dynamic caustics

Using the transparent material PMMA,a model experiment was carried out by the transmitted dynamic caustics to obtain a series of dynamic caustic photos.By the experimental results,the directional fracture characteristics of crack tips,such as dynamic stress intensity factors,expanding lengths and velocities,were discussed for different notch angles and depths.In addition,dynamic effects in V-notch blasting were explored according to the discussed results.It is shown that the cracks are subjected to tensile(...