摘要
采用数字激光动态焦散线实验系统,研究爆炸荷载作用下空孔缺陷对裂纹扩展行为的作用关系,以及裂纹扩展行为的规律。结果表明:在爆炸载荷作用下,空孔缺陷能够促使预制裂纹起裂并扩展,且空孔对爆生裂纹扩展方向有明显的导向作用;当爆生裂纹向空孔扩展时,空孔对爆生裂纹扩展行为有促进作用,使爆生裂纹与空孔贯通时速度和应力强度因子值增大;次生裂纹扩展速度和裂尖动态应力强度因子值都小于爆生裂纹相应值,且次生裂纹扩展初始阶段速度最大,裂纹的起裂韧度在0.8~1.1 MN/m^(3/2);随着空孔直径的增大,次生裂纹扩展长度先增大后减小,说明存在一个最优的空孔尺寸,使次生裂纹扩展距离最大,对裂纹扩展的促进作用最为显著。
The dynamic interaction of crack growth with cavity and the crack propagation dynamic behavior under explosion load were studied by using digital laser dynamic caustic test system. The results show that under the explosion load,the cavity can promote the crack initiation and propagation,and the hole has obvious guiding effect on the direction of the crack. When the crack develops toward the cavity,the cavity will promote crack to propagate. This promotion will make crack propagation velocity and stress intensity factor value bigger,and the velocity and stress intensity factor value of wing crack propagation are less than the corresponding value of explosion crack. The initial crack propagation velocity is the largest and the fracture toughness is between 0. 8-1. 1 MN/m^3/2. With the increase of cavity diameter,the crack growth length increases and then decreases,indicating that there is an optimal cavity size,which makes the crack propagation length the largest and the effect of crack propagation the most remarkable.
作者
杨仁树
左进京
方士正
陈帅志
王煦
YANG Renshu;ZUO Jinjing;FANG Shizheng;CHEN Shuaizhi;WANG Xu(School of Mechanics and Civil Engineering,China University of Mining and Technology（Beijing）,Beijing 100083,China;State Key Laboratory-for Geomechanics and Deep Underground Engineering,Beijing 100083,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2018年第12期174-178,共5页
Journal of Vibration and Shock
基金
国家重点研发计划(2016YFC0600903)
高等学校学科创新引智计划"111计划"(B14006)
国家重点实验室开放研究基金(GDUEZB201401)
