Influence of Composite Lay-Up on the Load-Carrying Capacity of Structures with Closed Rectangular Cross-Section

The purpose of this study was to carry out an experimental-numerical research of the influence of the composite layer system on the compressive strength of thin-walled eight-layer composite profiles with closed sections. The subjects of the study were thin-walled composite profiles made of carbon-epoxy composite by autoclave technique. The experimental studies utilized a universal testing machine, an optical deformation measurement system, and a digital microscope with a mobile working head. In parallel with the experimental studies, numerical simulations were conducted using the finite element method. Both the experimental studies and numerical simulations focused primarily on assessing the phenomenon of load-carrying capacity loss. The numerical simulations employed progressive damage analysis, which enabled the analysis of the obtained post-critical equilibrium paths. The research was conducted as part of a project funded by the National Science Centre, project no. 2021/41/B/ST8/00148.