Structural design of multimaterial columns accounting for multiple loads

Abstract

Compressive tests are performed on hollow carbon-fibre-reinforced-plastic (CFRP)/aluminium columns (H-C), foam-filled CFRP/aluminium columns (HF-C), and the corresponding net components. The energy absorption of the H-C column is lower than the total energy absorption of the net components under loading angles of 0° and 10°. The energy absorption of the HF-C column decreases under a 0° loading angle but increases under a 10° loading angle compared with the sum of the net components. Numerical models for the net components and the multimaterial hybrid columns are developed in LS-DYNA. Simulations indicate that the energy absorption reductions of external CFRP tubes primarily decrease energy absorption of hybrid columns, whereas energy absorption improvements in internal aluminium tubes primarily increase the energy absorption of hybrid columns, and that foam fillings can significantly improve crushing behaviours of aluminium tubes. Furthermore, parametric studies indicate that the energy absorption of hybrid columns can be increased by increasing the CFRP thickness and foam density. Finally, a discrete procedure is conducted to optimise the crashworthiness of hybrid columns with structural mass and crushing force constraints under multiple loads. Results indicate that compared with the baseline design, the energy absorption is improved by 7%, whereas the cost is reduced by 1.8%.