Local buckling strength of steel foam sandwich panels: Fid-Bau Portal

Local buckling strength of steel foam sandwich panels

Szyniszewski, S. / Smith, B.H. / Hajjar, J.F. / Arwade, S.R. / Schafer, B.W.

Abstract The objective of this paper is to provide and verify a new design method for the in-plane compressive strength of steel sandwich panels comprised of steel face sheets and foamed steel cores. Foamed steel, literally steel with internal voids, provides enhanced bending rigidity, exceptional energy dissipation, and the potential to mitigate local instability. In this work, Winter's effective width expression is generalized to the case of steel foam sandwich panels. The generalization requires modification of the elastic buckling expressions to account for panel non-composite bending rigidity and shear deformations. In addition, an equivalent yield stress is introduced to provide a single parameter description of the yielding behavior of the steel face sheets and steel foam core. The provided analytical expressions are verified with finite element simulations employing three-dimensional continuum elements and calibrated constitutive models specific to metallic foams. The developed closed-form design expressions are employed to conduct parametric studies of steel foam sandwich panels, which (a) demonstrate the significant strength improvements possible when compared with solid steel, and (b) provide insights on the optimal balance between steel face sheet thickness and density of the foamed steel core. This work is part of a larger effort to help develop steel foam as a material with relevance to civil engineering applications.

Graphical abstract Display Omitted Highlights ► Design method for compressive strength of steel foam sandwich panels is derived. ► Sandwich panels have higher compressive strength than slender solid plates. ► Dimensions of face sheets and the core are optimized to maximize the compressive strength.