The effects of bend-twist coupling on the post-buckling characteristics of composite laminated plates using semi-energy finite strip approach

摘要

In composite laminated plates various mechanical properties may be attained by changing the lay-up arrangement. The bent-twist coupling is one of the significant properties which dominate the mechanical performance of a laminated plate structure in large out-of-plane deformations. The effects of bend-twist coupling on the post-buckling behavior of composite laminated plates have been studied in this paper by implementing a finite strip approach based on the concept of a rigorous post-buckling solution for composite plates and plate structures, namely the semi-energy approach. All the plates are assumed to be symmetrically balanced laminates having uniform in-plane stiffness properties. As far as the out-of-plane stiffness properties are concerned, all the properties, except for the bend-twist coupling terms which are assumed to change from one laminate to another, are the same among different laminates. The orthotropic solutions have also been determined by precluding the bend-twist coupling terms. A comprehensive set of parametric studies have been carried out to investigate the effects of bend-twist coupling terms on the post-buckling load-displacement path, post-buckling deformations and stress distribution. The comparison between the results revealed markedly different behaviors among different laminates due to the bend-twist coupling effects. The outcome of the paper can help structural designers to have a better understanding of the effects of bend-twist coupling terms on the post-buckling behavior of laminated composite plates at the design stage.