The effect of complex crack shape on crack driving forces and crack tip stress fields: Experiment and FE analysis

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.