Face wrinkling of sandwich beams under pure bending

The paper is devoted to sandwich beams under pure bending. The local buckling problem is analysed. The analytical description of the upper face wrinkling is proposed. From the principle of stationary total potential energy, formulae describing critical stresses in the faces of the beam are derived. The algorithm for determining the critical stresses is shown. Two particular cases of the solution following the core properties are mentioned. The finite element model of the sandwich beam is formulated. The comparison of the results obtained from the proposed analytical model and from FEM analysis is shown for a family of sandwich beams with different thicknesses and core properties.