Predicting buckling-driven delamination propagation in composite laminates: An analytical modelling approach

Robust and efficient predictions of buckling-driven delamination propagation, enabled by a novel analytical modelling approach, are presented. The model considers full mechanical coupling (extension-shear, extension-bend, extension-twist/shear-bend bend-twist), contact mode-mixity thus significantly enhances the capabilities current approaches. A problem description in cylindrical coordinates enables evaluation energy release rate along boundary. uses an formalism to determine post-buckling deformation crack-tip element analysis employing force moment resultants acting on boundary rate. Composite panels with circular thin-film delaminations various multi-directional stacking sequences investigated for in-plane compressive loading. Predictions applied strains causing growth, i.e. threshold strain, show good agreement published experimental data 3D finite analysis. parametric study varying ratio size depth is performed. Based findings obtained, governing characteristics growth identified insight into damage tolerant design composite laminates which particular interest compression after impact (CAI) strength structures.