求解双材料界面裂纹应力强度因子的扩展有限元法  

COMPUTATION OF STRESS INTENSITY FACTORS FOR INTERFACE CRACKS BETWEEN TWO DISSIMILAR MATERIALS USING EXTENDED FINITE ELEMENT METHODS

作　　者：江守燕[1,2] 杜成斌[2] 顾冲时[1] 陈小翠[2] 

机构地区：[1]河海大学水利水电学院,江苏南京210098 [2]河海大学力学与材料学院,江苏南京210098

出　　处：《工程力学》2015年第3期22-27,40,共7页Engineering Mechanics

基　　金：国家自然科学基金项目(51309088;11372098;11132003;51139001);中国博士后科学基金项目(2013M530233);江苏省博士后科研计划项目(1301112C)

摘　　要：基于双材料界面裂纹尖端的基本解,构造扩展有限元法(e Xtended Finite Element Methods,XFEM)裂尖单元结点的改进函数。有限元网格剖分不遵从材料界面,考虑3种类型的结点改进函数:弱不连续改进函数、Heaviside改进函数和裂尖改进函数,建立XFEM的位移模式,给出计算双材料界面裂纹应力强度因子(Stress Intensity Factors,SIFs)的相互作用积分方法。数值结果表明:XFEM无需遵从材料界面剖分网格,该文的方法能够准确评价双材料界面裂纹尖端的SIFs。The asymptotic displacement fields for interfacial cracks between two dissimilar materials were used to construct enrichment functions for elements around crack tips in the extended finite element methods(XFEM). The discretization scheme in XFEM does not need to be aligned with material interfaces. Three types of enrichment functions: enrichment functions for weak discontinuities, heaviside enrichment functions and crack tip enrichment functions, are applied to formulate XFEM approximation. Subsequently, the interaction integral methods are derived for computing stress intensity factors(SIFs) of interfacial cracks between two dissimilar materials. Results show that the XFEM can accurately evaluate SIFs of interfacial cracks without the need of conforming meshes with material interfaces.

关 键 词：扩展有限元法 双材料 界面裂纹 相互作用积分 应力强度因子 

分 类 号：O346.1[理学—固体力学]