Flexural effects of sandwich beam with core junctions under in-plane bending

An improved six-step phase shifting method in digital photoelasticity was applied to calculate the full-field shear stress of cores in sandwich beam under in-plane bending. The load transfer and local stress concentration at the core junctions were investigated. The load transfer was realized by shear bands which connect the top and bottom sheet faces through adhesively bonded interfaces in the sandwich beam. The shear stress on both sides of the core junctions distributed continuously under pure bending, but distributed discontinuously and antisymmetrically under three-point bending. Different to the case under pure bending, the apparent shear stress concentrations existed on the core junction lines under three-point bending and maximized at the three-phase joints.