Experimental and numerical investigation of sandwich panels reinforced with horizontally arranged tubular cores under blast loading

Thin-walled aluminum tubes are widely recognized for their excellent energy absorption capability under dynamic loading due to their high plastic deformability. This study investigates the blast response of sandwich panels composed of horizontally arranged aluminum tube cores and steel face sheets, using combined experimental testing and finite element simulations in Abaqus/Explicit. Four panel configurations were examined to assess the influence of core tube number and face-sheet thickness on structural performance. Controlled blast experiments were conducted using PE4 explosive charges, and numerical simulations were performed with the Johnson-Cook material model and Conventional Weapon (CONWEP)-defined blast loading. The results demonstrate that increasing the number of core tubes enhances the overall panel stiffness. However, the reduced spacing between tubes limits their deformation capacity, which subsequently decreases energy absorption. Increasing the face-sheet thickness lowers displacement and stress concentration but also restricts energy dissipation in the core. The numerical model showed close agreement with experimental measurements, with less than 10% deviation in displacement and specific energy absorption. These findings provide valuable insight for the design of lightweight blast-resistant components in critical infrastructure, military vehicles, and protective engineering applications, and highlight the importance of optimally balancing core arrangement and face-sheet properties to improve both blast resistance and energy absorption in sandwich structures.