Three-dimensional (3D) constraint effects for part-through cracks, such as corner and surface cracks, emanating from stress concentrators play important role in damage tolerance design of structures, but have hardly been investigated in the frame of 3D elastic–plastic fracture theory. Here the ability of current elastic–plastic solutions to describe 3D constraints and their effects on crack tip fields of corner and surface cracks emanating from stress concentrators are systematically analyzed using finite element (FE) method. Distribution of the out-of-plane constraint factor T_z and corresponding in-plane constraint parameters Q_T and A_T can quantify the effect of stress concentration on crack tip fields. Good agreement between 3D elastic–plastic solutions (J-T_z, J-T_z-Q_T, J-T_z-A_T) and FE results is obtained for four typical specimens at relatively high and low loading levels, showing that these solutions can serve as the theory foundation for advanced damage tolerant analyses of engineering structures.

应力集中器产生的部分贯通裂纹（例如角裂纹和表面裂纹）的三维（3D）约束效应在结构的损伤容限设计中起着重要作用，但在3D弹塑性断裂理论的框架中很少进行研究。在此，使用有限元（FE）系统分析了当前弹塑性解决方案描述3D约束的能力及其对应力集中器产生的角和表面裂纹的裂纹尖端场的影响。平面外约束因子T _z以及对应的平面内约束参数Q _T和A _T的分布可以量化应力集中对裂纹尖端场的影响。对于四个相对较高和较低载荷水平的典型试样，在3D弹塑性解决方案（J - T _z，J - T _z - Q _T，J - T _z - A _T）和有限元结果之间取得了很好的一致性，表明了这些解决方案可以为工程结构的高级损伤容限分析提供理论基础。