Objectives  The goal of this article is to grasp the influence of panel spacing, plate thickness and other dimension parameters on the web buckling failure modes of I-type sandwich panels with aluminum foam. The change rules of its bearing characteristics during out-of-plane compression are revealed.

  Methods  The nonlinear finite element method was used to simulate the out-of-plane compression process of composite sandwich panels. The mechanical properties of aluminum foam were obtained from experiments. Aluminum foam was realized using an isotropic crushable foam model in the FEM simulation. The accuracy of the numerical simulation methods used in this article was verified by comparing the quasi-static test results with the simulation results.

  Results  The results show that with the decrease in the slenderness ratio, the failure modes of webs gradually transformed from material yield to plastic buckling, and five deformation modes such as plastic compression and low-order buckling appeared successively. Under high-order buckling, the stress curve will have a minimum value whenever a whole period deformation wave is generated. Under different slenderness ratios, the compressive strength of the composite sandwich panel appeared near the strain of 0.12, and was always maintained at about 9.36 MPa.

  Conclusions  The slenderness ratio is an important factor affecting the web buckling failure modes of composite sandwich panels. The compression mechanical properties of composite sandwich panels with different slenderness ratios have obvious differences which require attention in structural optimization design.