Buckling of sandwich beams with compliant interfaces

Buckling of elastic sandwich beams is analyzed accounting for the compliance of the interfaces between the skin and core. A relation between tractions and displacement jumps across the interfaces characterizes the interfacial compliance. Timoshenko co-rotational beam elements are used to discretize each layer of the sandwich. The dependence of the bifurcation load on the stiffness of the core and on the interfacial compliance are illustrated by considering examples of a sandwich beam with two sets of boundary conditions. It is shown that the load at bifurcation buckling is sensitive to the compliance of the interfaces and that a sufficiently large interfacial compliance can significantly decrease the bifurcation load.