The problem of honeycomb sandwich structures with moisture ingression can be avoided by replacing the honeycombs through chevron-folded cores. The application to real aircraft components often requires wedgeshaped sandwich. With folded cores, this kind of geometric shape can be obtained only by special folding schemes which have a significant influence on the mechanical performance. A comprehensive experimental investigation of the relation between folding geometry and structural properties of wedge-shaped folded cores (WSFC) is very time consuming and expensive. Therefore, a procedure based on numerical methods has been developed to predict the structural response of this kind of cores under compressive and shear loading. The approach is based on a numerical tool that provides finite element models of arbitrary WSFC as well as the explicit finite element solver LS-DYNA for simulation. These tools were applied to investigate the influence of the inner core geometry and different materials on the mechanical properties of WSFC structures. To verify these results, a test programme was conducted. Test samples were manufactured using a newly developed folding process. Also special test devices to determine the compression and shear properties of the WSFC specimens were developed. The achieved test results show a good agreement with the behaviour predicted by simulation.

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