Abstract
Stress and deformation of the sandwich box beam composed of face plates, sandwiched core and side beams under a three point bending moment are analyzed approximately by the use of the potential energy principle with consideration of orthotropic elasticity of the face plate and its additional deflection to that of the side beam. It is well known that the bending rigidity of a box beam decreases generally due to the shear-lag effect of the face plate. The decrease, however, presumably be somewhat prevented by a restraining action on the shear-lag effect in the face plate due to the shearing rigidity of the sandwiched core. The theoretical load vs. deflection curves and the strain distributions of the face plate agree well with the corresponding experimental results obtained for four types of test specimens with different dimensions and materials of the face plate.
