Cellular structures are efficient technological solutions for rockfall protection. A multi-scale approach is used to develop a cellular rockfall protection structure model for engineering purposes. The macroscopic structure is composed of meso-scale individual layers made up of rocky particles contained in wire netting cages, fine granular material, and reinforced embankment. Simple constitutive models were developed for the different mesoscale layers of the structure. Information is gathered from experiments at the layer scale to calibrate the parameters of the constitutive models. The capacities of the model are evaluated by comparisons between simulations and impact experiments on small structures. Despite quantitative differences, the comparative analysis highlights that the structure model can account for the main physical mechanisms occuring during the impact on sandwich structures. This analysis also emphasizes the model's applicability for engineering purposes.