Abstract
When the fatigue strength of welded structures is evaluated based on fatigue crack growth analysis, it is needed to set up the initial conditions of surface crack occurrence along weld toe.
Based on the investigation of interaction effect and coalescence behavior between adjacent surface cracks during their propagation, numerical simulation of fatigue growth life are performed for various situations of initial surface crack shape, size, number, occurrence region and distribution of initial cracks. The results agree well with experimental ones. Referring to above results, authors propose a procedure to set up the condition of multiple surface crack occurrence along weld toe, other than single initial crack for fatigue crack growth analysis.