Dynamic response and protection effectiveness of fluid filled concave multicell structure under air blast

Abstract

To harness the mechanical properties of concave multicell structures under explosive loading, a fluid filled concave multicell structure that combined the concave multicell pattern with a fluid filled structure was designed. The dynamic response and protective effectiveness of the designed structure under air blast loading were studied through experimental and numerical simulations, and their relationships with wave propagation process, structural deformation mode, protection effectiveness, and energy absorption were analyzed. The impact of fluid filling configuration and blast distance on the structure was also investigated. The results showed that the designed multicell structure had five typical deformation modes, and that changes in fluid filling configuration affected the stiffness distribution and local constraints of the concave multicell structure, altering wave propagation process, deformation, and energy absorption. It was also found that an increase in fluid filling caused a fluctuating decline in protective effectiveness, with the front plate and front core being the main energy absorbing parts. An alternative arrangement of fluid-filled and unfilled cells, which created a compound load propagation path combining solid, liquid, and gas media in various directions, effectively reduced the loading intensity, induced the structure to undergo horizontal compatible deformation and horizontal compatible-bulging deformation, and improved its protection effectiveness.