Three-dimensional mixed-mode stress intensity factor solutions for inclined surface cracks in plate structures subjected to uniaxial and biaxial uniform tensile loading

This study presents normalized three-dimensional mixed-mode stress intensity factor (SIF) distributions for inclined surface cracks in finite-thickness plates under uniaxial tension. Inclination angle, aspect ratio and ratio of crack depth to plate thickness were chosen as variable parameters affecting the problem. Mixed-mode SIFs distributions are given comparatively with independent graphs for different combinations of parameters and their effects are also examined separately. The results indicate that at a constant ratio of a/c, magnitude of the normalized mode-I SIF increases with increasing ratio of a/t and decreases with increasing inclination angle, while mode-II and mode-III SIFs increase up to a specific value of inclination angle and decrease afterwards. Having compiled an extensive solution library of mixed-mode SIFs, as functions of the aforementioned parameters, regression-based equations are also generated for the crack front's free surface and deepest penetration points. It is also presented, using the principle of superposition, that the given solutions can be used for inclined surface cracks in thin-walled plate structures, such as thin-walled cylindrical pressure vessels, ship and other marine structures subjected to biaxial uniform tensile loading.