Buckling and Initial Postbuckling Behavior of Sandwich Beams Including Transverse Shear

An asymptotic solution is presented for the buckling and initial postbuckling behavior of sandwich beams. The effect of transverse shear is included, and the shear correction is calculated from energy equivalency. The asymptotic procedure is based on the nonlinear beam equation (with transverse shear included), and closed-form solutions are derived for the critical load and for the load and midpoint deflection and axial shortening vs applied compressive load during the initial postbuckling phase. Illustrative results are presented for a few typical sandwich construction configurations, in particular, with regard to the effect of face sheet and core material system.