摘要
采用ABAQUS软件及粘聚裂纹模型对动态拉伸载荷下复合材料中垂直于基体-夹杂界面的基体裂纹与夹杂的相互作用进行了数值模拟。结果表明:在给定的界面强度下,当加载率(或应变率)低于某一临界值(临界应变率)时裂纹将沿基体-夹杂界面扩展,当高于该临界值时裂纹可以穿过界面在夹杂中扩展。此外,随着界面强度的提高,临界应变率降低;当界面强度超过一定值后,裂纹扩展方向将不受外部载荷影响,裂纹将沿自相似方向扩展;当界面强度低于该临界值时,裂纹将沿界面扩展;并且临界应变率随夹杂尺寸的增大而降低,即小夹杂更难于破坏。上述结果可为前人的混凝土动态实验数据提供合理的细观理论解释。
Simulation of the interaction between the matrix-crack and the inclusion in a composite under dynamic tensile loadings is carried out in this paper by using the ABAQUS software based on the so-called Cohesive Crack Model.The numerical results show,for a given interface strength,that the crack deflects into and propagates along the inclusion when the loading-rate(or the strain-rate) is lower than a critical value(the critical strain-rate),otherwise the crack penetrates through the interface and propagates in the inclusion.In addition,the critical strain-rate decreases with the interface strength.When the interface strength exceeds a certain value,the crack growth direction is not affected by the strain-rates,and the crack propagates along the self-similar extension direction.However,the crack deflects directly into and propagates along the interface when the interface strength is below the critical value.Moreover,the critical strain-rate decreases with the inclusion size,which implies that it is more difficult to be fractured for small inclusions.Such a conclusion provides a rational theoretical explanation with the mesoscale viewpoint to the reported experimental data for concrete under dynamic loadings by other researchers.
出处
《应用力学学报》
CAS
CSCD
北大核心
2011年第2期111-116,211,共6页
Chinese Journal of Applied Mechanics
基金
国家自然科学基金(10872035)
爆炸科学与技术国家重点实验室(北京理工大学)开放课题(YBKT09-05)
关键词
临界应变率
沿夹杂
穿夹杂
复合材料
裂纹
critical strain-rate,deflect along inclusion,penetrate through inclusion
