Experimental study on the behaviour of grid-scored foam-cored sandwich composites under low-velocity and quasi-static punch shear loads

Abstract

Grid-scored foams are core materials adapted to resin infusion systems used in marine vessels and aerofoil shell structures of wind turbine blades. Perforation resistance is critical in such constructions, and so the goal of this research is to analyse the energy absorption ability of sandwich composites with grid-scored foam core. Grid-scored foam contributed more to the energy absorption capacity of sandwich structures due to causing higher contact force compared with rigid foam under low-speed and quasi-static punch shear loads. At quasi-static punch shear tests, the energy absorption capability of grid-scored foams is more sensitive to test speed. Grid-scored foam improved the elastic energy absorption values of the sandwich structure under quasi-static punch shear tests. The perforation energy results obtained from the quasi-static tests of the grid-scored specimens showed a similar trend to the results obtained from the low-velocity impact tests. Compared with the damaged rigid-cored counterparts, grid-scored foam-cored sandwich specimens demonstrated higher damage tolerance in dynamic and static testing by limiting core crushing and face sheet-foam core delamination between resin channels.