Abstract This paper presented the effect of the complex crack shape on crack driving forces and crack tip stress fields, via experimental and numerical analysis results of the complex cracked tension (CC(T)) specimens. Fracture tests using CC(T) specimens are conducted using SA508 Gr.1a low-alloy steel, from which detailed crack shapes are measured before crack initiation and after crack growth. It is found that, after pre-cracking, the complex crack changes its shape such that elastic-plastic J and crack tip stresses become uniform along the crack front. The crack front shape remains similar during crack growth, so that elastic-plastic J and crack tip stresses remain uniform along the crack front.

中文翻译：

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复杂裂纹形状对裂纹驱动力和裂纹尖端应力场的影响：实验和有限元分析

摘要 本文通过复杂裂纹拉伸(CC(T))试样的实验和数值分析结果，介绍了复杂裂纹形状对裂纹驱动力和裂纹尖端应力场的影响。使用 CC(T) 试样的断裂试验是使用 SA508 Gr.1a 低合金钢进行的，从裂纹萌生之前和裂纹扩展之后测量详细的裂纹形状。研究发现，在预开裂后，复杂裂纹的形状发生变化，使得弹塑性 J 和裂纹尖端应力沿裂纹前沿变得均匀。裂纹扩展过程中裂纹前沿形状保持相似，因此弹塑性 J 应力和裂纹尖端应力沿裂纹前沿保持均匀。