摘要
裂纹尖端存在奇异应力场,该类奇异应力场所具有的高度应力集中将导致裂纹开裂.本文应用典型的J积分理论来划分裂纹尖端的积分路径,基于能量释放率理论对Ⅱ型裂纹尖端的复杂分叉情况进行研究.通过所建立的断裂模型求解出Ⅱ型裂纹多种分叉形式的能量释放率的解析解;导出了各种分叉构型的能量驱动力;提出了各种分叉构型的K-型开裂准则;给出了裂纹分叉的临界开裂角;确定了裂纹的分叉韧性与断裂韧性之间的关系.通过本文研究方法得出的裂纹分叉形式及裂纹分叉临界开裂角与已有实验结果十分吻合.
An energy-based fracture model for multiple crack-branching has been proposed and formulized for the Mode-Ⅱ crack-tip conditions. An analytical solution of the energy release rate for multiple crack-branching from a Mode-Ⅱ crack tip has been established, and the cracking angles have been analytically derived. The multiple crack-branching mechanism for quasi-static Mode-Ⅱ crack has been theoretically investigated, the relationship between the stress intensity factor K-based criterions and the fracture toughness for crack branching has been defined. The multiple crack-branching phenomena and the critical cracking angle obtained by this paper agree well with the experimental results.
作者
多依丽
谢禹钧
海军
刘明
孙麟
DUO Yi;XIE Yujun;HAI Jun;LIU Ming;SUN Lin(School of Mechanical Engineering, Liaoning Shihua University, Fushun 113001, Liaoning, China;College of Pipeline and Civil Engineering, China University of Petroleum, Qingdao 266580, Shandong, China)
出处
《力学季刊》
CSCD
北大核心
2019年第1期167-174,共8页
Chinese Quarterly of Mechanics
基金
国家重点研发计划(2018YFC0808500)
国家自然科学基金(11602234)
关键词
裂纹
裂纹分叉
J积分
断裂韧性
能量释放率
crack
crack-branching
J-integral
fracture toughness
energy release rate
