Mathematical models and experimental data for HDF based sandwich panels with dual corrugated lightweight core

Light layer honeycomb panels could replace traditional wood materials, if their stiffness and strength properties could be improved. The aim of this research was to design and determine elastic properties of sandwich panels (SPs) based on a dual corrugated HDF core. Stiffness matrix values of elements were determined by a numerical method. The 3D calculation results were compared with those of the homogeneous model. The calculation results were collated with those of experimental investigations. It was demonstrated that the linear elasticity modulus as well as the modulus of rupture of the SPs were comparable with mechanical properties of a particle board with identical thickness, while the SP has a 1/3 lower density. The panel core exhibited significant orthotropic properties. In the xy plane it could be characterized as an auxetic structure. The homogeneous model leads to results similar to those achieved from the 3D model and observed in experimental tests.