Stress intensity factors for surface cracks in single-edge notch bend specimen by a three-dimensional weight function method

Stress intensity factors for half-elliptical surface cracks at a semi-circular notch in a recently developed single-edge notch bend specimen are determined for a wide range of geometrical parameters using a three-dimensional weight function method. Two load cases of pin loading and uniform remote tension are considered. The results are in good agreement with abaqus/franc3d finite element analysis. It is found that the Ziegler-Newman engineering similitude approach (programmed into the Fatigue Crack Growth Structural Analysis life-prediction code) produces good results for a wide range in a/c ratios. Expressions by multi-variable curve fitting to the weight function results are presented for easy engineering applications.