Crashworthiness analysis and structural optimisation of multi-cell square tubes under axial and oblique loads

ABSTRACTSquare tubes have been widely used as energy absorption components. To investigate the influences of multi-cell configuration and loading arrangement on the crashworthiness of square tubes, eight kinds of multi-cell square tubes were numerically analysed under axial and oblique loads. Validation was performed against experimental data. According to the complex proportional assessment method, the T5-1 tube is found to have the best crashworthiness performance. Next, a parameter study was performed to analyse the effect of geometric parameters of the T5-1 tube on the crashworthiness. It was found that the s/b ratio and thickness have a significant influence on the energy absorption. The critical loading angle lies in the range of 10°–11°. Finally, a structural improvement design, with the straight tube changed to the taper tube, was implemented and the taper T5-1 tube was proposed. The results show that the taper T5-1 tube has better crashworthiness performance, compared with the original T5-1 tube.