Recent advances in the postbuckling analysis of composite laminated structures

The current demand for lightweight structures in a wide range of engineering applications leads to using thin-walled composite laminated structures whose behaviour is governed by buckling and postbuckling phenomena. Such a demand is pushing the borders of computational mechanics to enhance methods and algorithms for studying those structures' geometrically nonlinear responses. This work presents some of the authors' developments in analysing lightweight composite laminated structures. The literature survey introduces a family of finite elements known as MISS elements, where MISS stands for mixed isostatic self-equilibrated stresses. The description of those elements, which are derived from the Hellinger-Reissner functional, is followed by a discussion on their advantages concerning displacement-based elements when studying composite laminated thin-walled structures. Subsequently, a framework for the postbuckling analysis of composite structures with the MISS-4C element that uses the Koiter multi-modal approach is presented.