A review on works that investigate the mechanical behaviour of variable stiffness composite laminated panels is carried out in this paper. The review mostly focuses on buckling, failure and vibrations in laminates reinforced by curvilinear fibres, although other issues related to variable stiffness laminates are also addressed. The peculiarities in the formulation of curvilinear fibre reinforced plates are briefly described. As an illustration, the natural frequencies of vibration of variable stiffness composite laminated plates with curvilinear fibres are computed by an h-version type finite element code and are compared with the ones calculated using another model, based on a Third-order Shear Deformation Theory. Areas of research to explore on variable stiffness composite laminates are suggested.

The object of the research are short, thin-walled columns with an open top-hat cross section made of multilayer laminate. The walls of the investigated profiles are made of plate elements. The entire columns are subjected to uniform compression. A detailed analysis allowed us to determine critical forces and post-critical equilibrium paths. It is assumed that the columns are articulately supported on the edges forming their ends. The numerical investigation is performed by the finite element method. The study involves solving the problem of eigenvalue and the non-linear problem of stability of the structure. The numerical analysis is performed by the commercial simulation software ABAQUS®. The numerical results are then validated experimentally. In the discussed cases, it is assumed that the material operates within a linearly-elastic range, and the non-linearity of the FEM model is due to large displacements.