Buckling of a thin, tension-loaded, composite plate with an inclined crack

A numerical study of the local buckling and fracture response of a thin composite plate with an inclined crack and subjected to tension is presented. Local buckling of the unsupported edges of the crack occurs due to compressive stresses caused by a Poisson effect in the neighborhood of the crack. The relationship between fracture of a plate with a crack and the local buckling and postbuckling responses of the plate is established through a geometrically nonlinear finite-element analysis in conjunction with concepts from fracture mechanics. The analysis is based on a co-rotational form of the updated Lagrangian formulation that is implemented with a triangular shell element that includes transverse shear deformation effects. The potential energy release rate results are computed for a predetermined radial crack propagation direction that coincides with the location of the maximum stationary strain energy density near the crack tip. The results indicate that the local buckling load increases and the potential energy release rate decreases as the crack orientation changes from a transverse crack to a longitudinal crack aligned with the direction of the applied tension load. The effect of stacking sequence on the local buckling load and on the energy release rate for specific crack orientations is also discussed. (C) 1997 Elsevier Science Ltd.