基于扩展有限元法的弹塑性裂纹扩展研究  

Elastic-plastic crack propagation based on extended finite element method

作　　者：杨志锋[1] 周昌玉[1] 代巧[1] 

机构地区：[1]南京工业大学机械与动力工程学院,江苏南京211800

出　　处：《南京工业大学学报（自然科学版）》2014年第4期50-57,共8页Journal of Nanjing Tech University(Natural Science Edition)

基　　金：国家自然科学基金(51075199);江苏省普通高校研究生科研创新计划(CXZZ11_0341)

摘　　要：为了得到紧凑拉伸(CT)试样应力强度因子和J积分,分别采用传统有限元法、扩展有限元法以及试验方法对其进行计算。在弹性情况下,扩展有限元法和传统有限元法获得的应力强度因子相近,并且与ASTM E1820—05a解相差很小。在弹塑性情况下,扩展有限元法和传统有限元法获得的应力场和J积分有较大的差别,扩展有限元法得到的J积分相对于传统有限元法的结果与实验值更吻合。结果表明:扩展有限元法由于考虑了裂纹扩展,比传统有限元法可以更加准确合理地模拟弹塑性裂纹扩展。Stress intensity factor and J-integral of compact tension（ CT） specimen were investigated by traditional finite element,extended finite element and experimental methods. The stress intensity factor obtained from extended finite element was nearly the same as that from conventional finite element,and they agreed with the ASTM E1820-05 a under the elastic condition. But under elastic-plastic condition,there were great differences in stress field and J-integral acquired from extended finite element and traditional one. The J-integral based on extended finite element was in agreement with the experimental results from traditional finite element. Result showed that the extended finite element was more accurate and reasonable than traditional finite element for the elastic-plastic crack propagation problem,since the crack growth was considered in the extended finite element.

关 键 词：扩展有限元 裂纹扩展 应力强度因 J积分 

分 类 号：O346.12[理学—固体力学]