Investigation of impact and vibration behaviours of composite honeycomb sandwich shell panels with foam reinforcement

The impact and vibration behaviours of composite honeycomb sandwich shell panels with foam reinforcement (RF-CHSSPs) are researched analytically and experimentally. Initially, a dynamic model of the RF-CHSSPs is created to predict the vibration and impact characteristics, with the equivalent Poisson's ratio and elastic modulus of the core are determined to consider the effect of the ratio of honeycomb cells and foam. Time-domain minimum residual technique and Broyden iterative method are used to solve the natural frequency and resonant response by using von Karman's theory and the high-order shear deformation shell principle. Also, based on the quasi-static method and modified failure criteria, the curves of impact displacement–time, load-time and load–displacement are plotted. Meanwhile, the low-velocity impact and base vibration excitation experiments are carried out on the prepared RF-CHSSP specimens to verify the accuracy of the established model and the vibration and impact suppression ability of foam on the composite honeycomb sandwich shell panels. The results show that the maximum calculated errors of impact displacement, load, natural frequency and resonance response are 5.1, 5.8, 4.7 and 9.0%, respectively. Moreover, for the specimens without foam reinforcement, the impact contact force of the RF-CHSSP specimens is improved by 13.2%, and the impact displacement and resonance response are reduced by 15.8 and 96.6%, respectively. The manufacturing technology, approach to problem resolution and valuable discoveries of current study show the way forward for the creation and application of such sophisticated shells.