The post-critical behaviour of compressed plate with non-standard play orientation

Abstract

Thin-walled carbon/epoxy composite plate elements with a central cut-out under compressive loading are investigated. The work focused on the original concept of this element, for use as elastic or load-bearing element and whether possibility to shape their structural rigidity by changing the cut-out geometry or the laminate’s lay-up. The lowest buckling mode exhibits a small postcritical rigidity and is reached at low loads. The calculations carried out earlier show that plates with forced higher form of buckling are characterized by stable, progressive paths of post-critical equilibrium, enabling their use as elastic elements. The aim of the study, partially revealed in this abstract, requires a thorough analysis of the effect of the B matrix form on the coupled composite behaviour. Coupling stiffness matrices of unsymmetrical laminates have been thoroughly described by, among others, York, Altenbach. The commercial ABAQUS program using the finite element method was used to develop the discrete model and perform numerical calculations. Experiment was performed on a universal testing machine. The obtained results are of significant practical importance in the design of structures with elastic elements, allowing to achieve the required maintenance characteristics of the device.