Performance evaluation of Reinforced honeycomb structure under blast load

Abstract

In this study numerical simulations were carried out to explore the response of the reinforced honeycomb sandwich structure with varying cell size (7, 10 and 15 mm), node length (25, 37.5 and 50 mm) and cell wall thickness (0.1 , 0.2 , 0.3 and 0.4 mm). The honeycomb structure made of aluminum alloy 8011 were subjected to low intensity blast loads by varying mass of TNT (10 g, 15 g, 20 g and 25 g) and standoff distance (200 mm, 250 mm and 300 mm). Commercial finite element code LS-DYNA was employed to carry out numerical simulations for both conventional and reinforced honeycomb sandwich structure keeping identical geometrical and blast load parameters. The numerical model was validated with the global deformation and resulted impulse, reported in the literature. The deformation of the back face sheet was considered as major parameter to establish blast resistance of the core. Failure mechanisms of reinforced honeycomb was characterized as fully folded region, partially folded region and clamped region. Reinforced honeycomb sandwich outperformed the conventional honeycomb sandwich structure of identical geometry parameters under blast loads. Increase in cell-wall thickness and node length enhanced the blast resistance whereas increment in cell size reduced the blast resistance of the reinforced honeycomb sandwich structure.