定向断裂双孔爆破裂纹扩展的动态行为  

Dynamic behaviors of crack propagation in directional fracture blasting with two holes

作　　者：杨仁树[1,2] 王雁冰[1,2] 岳中文[1,2] 刘国庆[1] 

机构地区：[1]中国矿业大学(北京)力学与建筑工程学院,北京100083 [2]中国矿业大学(北京)深部岩土力学与地下工程国家重点实验室,北京100083

出　　处：《爆炸与冲击》2013年第6期631-637,共7页Explosion and Shock Waves

基　　金：国家自然科学基金委员会与神华集团有限公司联合基金重点项目(51134025);中央高校基本科研业务费专项基金项目(2009QL15;2009QL04)~~

摘　　要：利用爆炸加载动态焦散线测试系统,研究了双炮孔切槽方式下、同时起爆、两炮孔间贯穿裂纹和炮孔外侧裂纹扩展的动态行为。实验结果表明:贯穿裂纹尖端并未直接相遇,而是一上一下,相遇后继续扩展,并向异方已有的裂纹方向移近。裂纹扩展速度和加速度均呈现波浪起伏式的涨落变化。同一条裂纹扩展的速度和加速度的峰值交替出现,加速度先达到峰值,速度再达到峰值。动态应力强度因子KⅠ由最大值迅速减小,然后经过反复振荡后,又逐渐增大,并达到第2个峰值,之后开始减小。裂纹扩展的过程中,KⅡ基本都小于KⅠ。贯穿裂纹尖端的动态应力强度因子大于外侧裂纹的。动态能量释放率由最大值迅速减小,振荡变化后第2次达到峰值,又逐渐减小。Using a dynamic caustics blast loading system,the paper studied the dynamic behavior of perforated crack propagation between two holes and lateral crack propagation on the condition of grooving with two borehole blasting and simultaneous initiation.As can be seen from the results,the perforated crack tips did not directly encounter,but one was at the top and the other was below,met and went on propagation,then got closer to the direction of the anisotropic existing crack.The velocity and acceleration showed a type of fluctuation changes as wave.For one crack,the acceleration firstly came to the peak,then the velocity came to the peak.The dynamic stress intensity factor KⅠ decreased rapidly from the maximum,oscillated,and up to the second peak,then decreased.KⅡ was almost smaller than KⅠ.The stress intensity factor of the perforated crack tip was almost greater than that of the lateral crack.The dynamic energy release rate decreased rapidly,oscillated,and then decreased.

关 键 词：固体力学 动态行为 动态焦散线 裂纹扩展 切槽爆破 贯穿裂纹 

分 类 号：O346.1[理学—固体力学]