应力场强计算裂纹应力强度因子的方法研究  

STUDY OF THE COMPUTATION OF STRESS INTENSITY FACTOR BY STRESS FIELD INTENSITY

作　　者：应中伟[1] 冯蕴雯[1] 薛小锋[1] 冯元生[1] 

机构地区：[1]西北工业大学航空学院,西安710072

出　　处：《机械强度》2009年第1期117-121,共5页Journal of Mechanical Strength

基　　金：国家自然科学基金(10372082);航空基金(03B53008;2006ZD53);西北工业大学科技创新基金资助~~

摘　　要：探讨通过应力场强得到应力强度因子的方法,并以典型的四类平面裂纹状态为例,着重探讨各类平面裂纹如何应用该方法计算应力强度因子。结果显示,所提方法能快速地求解各类裂纹布置的应力强度因子,可为断裂力学中裂纹扩展、断裂判断问题以及疲劳多裂纹问题的研究提供良好的支持。Currently, there is some difficulty for the computation of stress intensity factor （SIF） in engineering because of comphcated computation. The purpose of this study is to build the relation between SIF and stress field intensity, and to obtain SIF more easily by stress field intensity. The deduction bases on two basic types of crack, which are mode I crack and mode n crack. For mixed mode I , Ⅱ crack and common complex planar crack problems, stress field equation at crack tip can be obtained by application of superposition principle to two basic types of crack. And then SIF can be computed by substituting the stress field equation obtained into the stress field intensity expression. To verify the proposed method, four types of crack configuration were analyzed. In the analysis, the FE（finite element）-code MSC. Nastran had been used. Results were evaluated by comparing with numerical solution. Relative errors of four crack configurations are less than 5%, and mostly within 1%-3%. It indicates that complex problem＇s SIF can easily and accurately be computed by proposed method. This method can lend good support to the research in fracture mechanics, such as crack growth problem and fracture failure problems.

关 键 词：应力强度因子 应力场强 裂纹 缺口 

分 类 号：O346.1[理学—固体力学]