Structurally graded core inserts in sandwich panels

Core inserts in sandwich panels substitute parts of the original core material in a sandwich element, and the main purpose of the core inserts is to supply a local reinforcement of the sandwich panel for a subsequent introduction of the external loads. The new design of the core insert substantially diminishes the level of impairing local effects in the faces. The suggested insert is structurally graded by means of shaping insert boundaries to be inclined with respect to the sandwich faces, which provides smoothing of material discontinuities at the junction of different materials. The new design of the core insert is studied experimentally, and the design parameters of the core insert are studied with the help of the finite element modelling (FEM).