Crashworthiness of multi-cell circumferentially corrugated square tubes with cosine and triangular configurations

Multi-cell and multi-corner configurations are the most common methods to improve the crashworthiness performance of thin-walled tubes. However, the crashworthiness of a thin-walled tube combining these two configurations has not yet been evaluated. This paper proposed a series of multi-cell circumferentially corrugated square tubes (CCSTs) in which multi-corner configurations were achieved by introducing cosine and triangular corrugations. The crashworthiness of these multi-cell CCSTs were investigated under multiple loading angles. The complex proportional assessment (COPRAS) method was used to select the optimal structures. The results showed that the cosine and triangular multi-cell CCSTs with crisscross ribs, namely, C1 and T1 in this paper, exhibited the best performance. Then, two different multi-objective optimization methods were used to determine the optimal geometric parameters of C1 and T1. The results showed that one optimization method mainly balanced the crashworthiness performance at different loading angles but did not improve the performance, whereas the other optimization method significantly improved the crashworthiness of the tubes.