Nonlinear Post-Buckling Behavior of Sandwich Tapered Columns

This paper presents the nonlinear post-buckling behavior of sandwich tapered columns. The sandwich members are laterally-symmetrically laminated against the mid-depth of a circular cross-section in which the radius varies along the longitudinal axis. The flexural rigidity of sandwich members is explicitly formulated and then applied to estimate the nonlinear post-buckling response of columns with sandwich members. Two nonlinear differential equations governing the post-buckled elastica of simple and cantilever columns, respectively, are derived and numerically solved to determine their elastica. Approximate buckling loads are provided, which are equivalent loads with very small deformation of the top end of the columns. Numerical examples are given to ascertain the effect of geometrical and material parameters of sandwich tapered columns in terms of equilibrium path, elastica and buckling load.