Bending resistance of thin-walled multi-cell square tubes

•Bending collapse of square tubes with partition plates is investigated.•Partition plates are introduced in longitudinal direction and in cross-section.•Parametric analyses are performed to study the influence of various factors.•Performance of square tubes is improved by introducing partition plates.•Suggestions are offered for design of structures under transverse loading.

The bending resistance of multi-cell square tubes under three-point bending is investigated in this study. Partition plates are introduced in longitudinal direction and cross-section of square tubes to form multi-cell structures. Numerical simulation of the three-point bending test is carried out by nonlinear finite element code and experimental test is conducted to validate the numerical model. Parametric studies are then performed to investigate the influence of the number of cells, load conditions and other geometrical configurations on the bending resistance. Results reveal that the number of partition plates has important influence on the bending resistance of the structure and more partition plates do not necessarily lead to high energy absorption efficiency. The optimum configurations of the structures are found out and some valuable suggestions are offered for multi-cell structures under transverse loading.