An Individual Core Structure of a Sandwich Beam Due to the “Broken Line” Theory of the Shear Effect–Three-Point Bending

The work concerns a sandwich beam with an individual core structure giving a shear effect exactly in accordance to the “broken line” theory. According to the general theoretical scheme of a planar cross section deformation, longitudinal displacements, strains and stresses are analytically formulated. Moreover, the unknown deformation function of the core, with consideration of the classical shear stress formula, is analytically derived. Based on the condition regarding the linear deformation function of the core, according to the “broken line” theory, the differential equation is obtained. The solution of this equation is the sought individual core structure. Then, the bending problem of a clamped sandwich beam under three-point bending is studied.