A method for modeling the local and global buckling of delaminated composite plates

An analytical methodology is presented for predicting the buckling initiation of delaminated composite plates. Both global and local sublaminate buckling deformation modes are predicted for rectangular plates of any thickness. The global behavior of the delamination zone is accounted for by summing the individual stiffness contributions of each sublaminate constituting the delamination zone. This allows for the delamination zone to be treated as a single plate when performing global buckling predictions. Local buckling predictions are obtained by modeling a sublaminate adjacent to the surface as a separate elliptical plate. These analytical predictions compare closely with the results of detailed finite element models investigating several cases of delaminated plates. The methodology presented is found to be accurate for the cases considered and versatile as it can accommodate plates of any aspect ratio and having arbitrarily sized and located delaminations. (C) 1999 Elsevier Science Ltd. All rights reserved.