Crush resistance of square tubes with various thickness configurations

•Square tubes with uniform and nonuniform wall thicknesses are fabricated and tested.•Wall thickness shows great influence on crushing behavior of the tubes.•Numerical simulations are carried out and compare well with experiment.•Theoretical model is established for corner elements with nonuniform thickness.

The crush resistance of corner elements with various thickness configurations is investigated in this paper. Experimental study and numerical analyses are performed for square tubes with uniform and nonuniform wall thickness. The variation of wall thickness is found to have great influence on both deformation mode and force responses of the tubes. Two theoretical methods are proposed to predict the mean crushing force of the corner elements with nonuniform wall thickness. One is based on data fitting with average wall thickness and another is a newly proposed analytical model. Both methods can give satisfactory predictions for crush resistance of corner elements developing inextensional mode.