Effect of structural configuration on air blast resistance of polyurea-coated composite steel plates: Experimental studies

Abstract The effect of structural configuration on air blast resistance of polyurea-coated composite steel (PCCS) plates was experimentally evaluated. Four types of PCCS plates with identical total areal density were subjected to different air blasts. The failure modes and energy dissipation mechanisms (EDMs) were identified from the stress wave propagation perspective. A quantitative analysis of energy dissipation was performed in different PCCS plates. The results show that the failure modes of PCCS plates varied significantly with change in structural configuration due to impedance mismatching between steel and polyurea layers. The EDMs of polyurea layers varied with change in blast intensity. Petalling/spalling, central plugging, and stretching deformation were the main EDMs of polyurea layers for rear-side sprayed, impact-side sprayed, and sandwiched PCCS plates, respectively. Rear-side sprayed and sandwiched PCCS plates had superior air blast resistance to monolithic steel counterparts, whereas impact-side and both-sides sprayed PCCS plates had inferior air blast resistance to monolithic steel counterparts. The steel layer played a key role in dissipating kinetic energy in a PCCS plate regardless of structural configuration and blast intensity. The energy dissipation capacity of polyurea layer could be more sufficiently utilized under relatively low-intensity air blasts.