A novel design of blast proof sandwich structure with hybrid skin

Abstract

In the present modern age, explosive terrorist attacks are increasing day by day. Explosive attacks can take place anytime and anywhere. This is a hazard to both people and property. Hence, blast-proof structures are in demand for the current era to protect humans and properties. An effort has been made to design a novel blast-proof sandwich to fulfil this requirement. A sandwich structure made of steel was designed using a square honeycomb core (Model-1). The blast resistance analysis of the designed honeycomb sandwich structures was performed on ABAQUS/Explicit. The modelled sandwiches were subjected to conventional weapons effects program (CONWEP) air-blast loads ranging from 1 kg to 3 kg trinitrotoluene (TNT) for a fixed stand-off distance (SoD) of 150 mm. After the mesh convergence study and validation of the Model-1 with experimental results available in the literature, the 5 mm steel front skin was replaced by 1.5 mm steel/2 mm carbon fibre reinforced polymer (CFRP)/1.5 mm steel hybrid skin for Model-2 to reduce the weight of the structure with improved blast performance. In Model-3, both the 5 mm steel front skin and the 5 mm steel back skin were replaced by 1.5 mm steel/2 mm CFRP/1.5 mm steel hybrid skins for a further reduction in the weight of the structure. The blast resistance of sandwich configurations was evaluated in terms of the protective back skin deflection during blast loads. The use of hybrid skins in a sandwich structure drastically improves blast resistance in terms of smaller skin deflection. The square honeycomb core used sandwich with the hybrid front skin (Model-2) has the best blast proof characteristics and is recommended for armoured vehicles and skid plates of automobiles to protect the lives of humans.