POSTBUCKLING OF LAMINATED COMPOSITES WITH DELAMINATIONS

Postbuckling analysis of laminated composites with delaminations is pr esented. A finite element method based on a layerwise laminated compos ite plate theory is developed to formulate and solve the problem. Geom etric nonlinearity in the sense of von Karman and imperfections in the form of initial global deflection and initial delamination openings a re included. A simple contact algorithm which precludes the physically inadmissible overlapping between delaminated surfaces Is proposed and incorporated into the analysis. Numerical results are obtained for th rough the-width delaminations addressing the effects of the magnitude and direction of initial imperfections, laminate stacking sequence, an d the contact condition between the delaminated surfaces on the postbu ckling response. The proposed approach is shown to be efficient and po werful for solving the class of problems mentioned.