On the postbuckling of flawed shear panels considering crack growth effect

In practical applications, the load bearing capability of slender plates can be affected by the existence of flaws resulting from a number of material deterioration (corrosion, fatigue, etc.). In the present work, a numerical analysis on the residual strength and post-buckling behavior of flawed shear panels using FE method is performed. Using a continuum damage mechanics model, the possibility for a ductile crack to grow under loading is considered. This approach allows us to investigate the role of crack growth in materials with different capabilities to accommodate plastic deformations at the crack tip, as well as geometry effect on the material crack resistance, due to loss of constraint. The effect on the buckling load, ultimate load and postbuckling response of shear panels varying both geometry characteristics and materials (such as initial crack length, slenderness ratio, panel boundary conditions, material properties, etc.) is investigated. Results indicate that crack growth can play a relevant role in the response of shear panels, especially for those materials in which ductile tearing can occur in the early stages of loading. The damage mechanics model used in this work offered the possibility to simulate the occurrence of ductile crack growth based on material properties, without the need of arbitrary assumptions on the crack advance process.