Delamination buckling and growth of flat, cross-ply laminates

Abstract

A one-dimensional model is presented in order to predict (a) delamination buckling loads of an across the width delaminated and axially loaded laminated plate and (b) the ultimate load-carrying capability of the above geometry, when delamination growth can take place. In order to study the possibility of spreading of the damaged (delaminated) area to the undamaged area, the post-buckling solution is employed. The energy release rate has been used to determine whether the delamination growth is stable or unstable. The results reveal that for a relatively small delamination length the buckling loads serve as a measure of the load-carrying capacity of the damaged plate, while for a relatively large delamination length, the plate could carry larger loads depending on the fracture toughness of the plate material. Moreover, the present model can be used to study the effect of the presence of coupling between bending and stretching on delamination growth. Note that for such geometries the possibility of bifurcational buckling does not exist, regardless of the level of the applied load.