矿业科学学报2026，Vol.11Issue(2)：317-327,11.DOI:10.19606/j.cnki.jmst.2026007
微差爆破作用下多条定向裂纹扩展行为试验研究
Experimental study on the propagation behavior of multiple directional cracks under delay blasting
摘要
Abstract
Refined delay blasting using digital electronic detonators has been widely used in rock break-ing engineering,where notched borehole could control the direction of explosion-induced crack propa-gation.This study investigates how delay time affects the propagation behavior of multiple directional cracks through dynamic caustics experiment for delay blasting on specimens with multi-directional not-ched boreholes to unveil crack propagation path and mechanical properties of crack tip.Results show that multi-directional notched boreholes could effectively control the direction of crack propagation.In both groups of specimens,the main cracks generated by the explosion extended along the notched di-rection,with cracks from the first borehole longer than those from the second.At 30 μs delay time,cracks between the boreholes showed a"hook-like"distribution at their convergence point,with a lar-ger deflection angle in the cracks from the rear borehole.Propagation velocities,dynamic stress intensi-ty factors and dynamic energy release rates exhibited consistent trends,showing significant increase when the cracks approached each other.Cracks from the first borehole displayed pronounced fluctua-tions.Both cracks transformed into I-II mixed mode and then propagated alternately.At 180 μs delay time,the directional control provided by the second borehole's notch was weakened horizontally and formed a"Y-shaped"crack distribution,significantly affecting crack propagation velocity of the first borehole.This study offers references for optimizing delay times and improving rock breaking efficiency.关键词
微差爆破/定向裂纹/动态焦散线/裂纹扩展速度/动态应力强度因子/动态能量释放率Key words
delay blasting/directional crack/dynamic caustics/crack propagation velocity/dynamic stress intensity factor/dynamic energy release rate分类
矿业与冶金引用本文复制引用
郭东明,王恒恺,张伟,陈今,刘康,高庆礼..微差爆破作用下多条定向裂纹扩展行为试验研究[J].矿业科学学报,2026,11(2):317-327,11.基金项目
国家自然科学基金(51974315) （51974315）
