中文摘要：

为了进行空间复合型裂纹的应力强度因子K与应变能释放率G的关系研究,应用断裂力学理论,基于最大主应变准则对Ⅰ型裂纹、Ⅲ型裂纹以及空间复合型裂纹的扩展进行理论分析,应用主应变下的空间复合型裂纹开裂断裂准则推导出Ⅰ-Ⅲ复合型裂纹K与G的关系式,并利用有限元软件ANSYS对关系式进行验证。结果表明,该关系式计算结果与有限元软件的计算结果吻合较好,相对误差在允许范围内。

英文摘要：

Based on the maximum principal stress criterion,propagation of the mode Ⅰ crack,mode Ⅲ crack,and spatial mixed mode crack were theoretically analyzed usingfracture mechanics theory.Then,the relationship between the stress intensity factor K and strain energy release rate G was studied.A formula that relates K to G for mixed mode cracks Ⅰ-Ⅲ was established based on the fracture criterion of the spatial mixed mode crack under principal strain.By comparing results of the formula with that of the finite element software ANSYS,it was determined that the former was in accordance with the latter.