Behaviour of PU-foam/glass-fibre composite sandwich panels under flexural static load

Composite sandwich panels were developed for the sail boat hull using glass-fibre/epoxy composite facing and polyurethane foam core. These light weight structures were tested through four-point bending tests to characterize their flexural behaviour. The material exhibited an initial linear elastic behaviour followed by non-linear behaviour. Finite element analysis of the sandwich panels, accounting for the materials and geometrical nonlinearity as well as the cohesive nature of the skin–core interaction, was performed to analyse the flexural behaviour of the structure. Good agreement has been observed between the numerical and experimental response up to the failure. Moreover, the experimental results were compared with the predictions of the classical sandwich theory. The theoretical predictions well represented the linear flexural response of the sandwich panels, while deviates as the load increase up to failure due to the theory limitations.