Evaluation of bending strength of lattice-filled tubes with rectangular cross section

In this study, the bending strength of lattice-filled rectangular tubes under three-point loading has been studied using a nonlinear finite element analysis. The failure mechanism of lattice-filled tubes can be classified in four modes: tube wrinkling, tube yielding, core shear and tube denting, which are basically similar modes for the lattice sandwich panels. Based on this fact, the analytical equations for predicting the failure load for lattice tubes are proposed, and their accuracies are discussed by comparing the failure loads yielded by a finite element analysis with their predictions for the tube wrinkling, yielding and core shear modes.