Cambridge University, Engineering Department, Trumpington Street, Cambridge CB2 1PZ, UK
Abstract:
Failure modes for sandwich beams of GFRP laminate skins and Nomex honeycomb core are investigated. Theoretical models using honeycomb mechanics and classical beam theory are described. A failure mode map for loading under 3-point bending is constructed, showing the dependence of failure mode and load on the ratio of skin thickness to span length and honeycomb relative density. Beam specimens are tested in 3-point bending. The experimental data agree satisfactorily with the theoretical predictions. The effect of honeycomb direction is also examined. The concept of a failure mode map is extended to give a useful design tool for sandwich panels manufacturers and their customers.