Analysis of Sandwich Panels with Formed Faces

The analysis of foam-filled sandwich panels with light gage, cold-formed metal faces is studied both experimentally and theoretically. Moments and shears affecting the core and those arising from the bending of the rigid faces are combined in the theory. Formulated as an ordinary second order differential equation, and using boundary conditions, expressions are developed for deflection and for flexural stresses in the faces and shear stresses in the core. Experimentally, four different sandwich panels were subjected to uniform loading on simple spans. Strain gages and deflection dials were used. Experimental and theoretical deflections and stresses are in reasonable agreement. Both approaches show a reversal of stresses along the profiles of the formed faces due to bending of such faces about their own centroidal axis, which indicates a plane section of such sandwich panel does not remain plane under bending. The theory is applicable to panels with either one or two formed face(s) and faces of different or the same materials. In case there is only one formed face, the other face is flat.