Post-buckling behavior of composite panels in the presence of unstable delaminations

The analysis of the non-linear behavior of delaminated composites panels under compression is considered. A modification to the incremental continuation method (by Riks) for the analysis of the non-linear behavior of damaged composites is proposed to improve the numerical treatment of the analysis of unstable delamination growth. The theoretical formulation of this modification is first presented in conjunction with a general formulation of the continuation method and the modified virtual crack closure technique (MVCCT) for the evaluation of delamination growth. Finally, numerical results for delaminated composite plates through the width and circular delaminations are presented and compared with existing experimental and numerical data