A numerical investigation of protective structures subjected to high intensity blast

High-intensity blast loads provide significant risks to protective structures utilized in defence and vital infrastructure. Conventional materials frequently do not satisfy both weight and strength criteria. This work quantitatively examines the performance of Fiber Metal Laminates (FMLs) with different honeycomb core geometries under blast loading, utilizing explicit analysis and the CONWEP function in ABAQUS-CAE. Simulations were performed on square, hexagonal, octagonal, and circular core sandwich panels. The material behavior was characterized by Johnson-Cook plasticity for AA-5052 aluminium and Hashin failure criteria for Kevlar and basalt-epoxy composites. The Hashin failure criterion for composite laminates and the Johnson–Cook plasticity model for AA-5052 aluminum were used to characterize the material behavior. According to the results, under the same blast conditions, the hybrid Al/K/B/Al configuration reduced front-face bending by 19.39% and increased energy absorption by 15.41% when compared to conventional FMLs. Due to impedance mismatches at the Kevlar–basalt interfaces, the hybrid circular cores showed delayed failure initiation and enhanced stress-wave redistribution. These effects showed that circular-core FMLs, which are generally less efficient, perform better when hybridized than square or hexagonal cores, reversing the traditional energy absorption trend. Dynamic response analysis and Nurick’s dimensionless parameters were used for verification, which confirmed a strong correlation between the theoretical and simulated deformation behavior. The results provide a computational framework that has been validated for forecasting blast performance in hybrid FMLs. Al/K/B/Al sandwich panels are perfect for lightweight protective applications like vehicle armor, modular barricades, and rapid-deployment field shelters because they can withstand up to 80 kg TNT blasts while maintaining reduced mass and deflection.