Blast response of aluminium/thermoplastic polyurethane sandwich panels – experimental work and numerical analysis

This article presents experimental and numerical results following blast tests on a polyether grade thermoplastic polyurethane (TPU). Aluminium alloy (AA) 2024-T3 skins were used as facings to enhance the blast resistance of sandwich structures with TPU cores and varying thicknesses. The experimental results highlighted an improvement in blast resistance with the addition of skins to the TPU core. Increasing the thickness of the TPU core in the sandwich panels served to increase the blast resistance of the structure. For example a 20 mm core offered a blast resistance that was 50.2% higher than an equivalent 5 mm core and 71.2% higher than a plain (i.e. no skin) 5 mm TPU core. Numerical simulations of the blast response of the TPU panels were conducted by converting the explosive loading regime applied to the panels to a simplified pressure pulse loading. Good agreement was obtained between the numerical and experimental results for the back face deflection profiles through the central cross-sections of the panels.