Energy absorption performance of hybrid cross section tubes under oblique loads

Abstract

Compared with the excellent energy absorption performance under axial loading, thin-walled tubes are vulnerable to unstable global bending under oblique loading. To improve the energy absorption performance of tubes under oblique loads, a novel designed tube with hybrid cross section is studied in this paper by adding ribs at the bottom end of the tube. Quasi-static compression experiments of square (single-cell) tube, single-double hybrid tube, double-cell tube under three oblique loads were performed to verify the finite element model. Based on the verified finite element model, the energy absorption performance was compared between the single cell tube (SCT), double cell tube (DCT) and single-double hybrid tube (SDHT) under seven oblique loads. Results showed that the SDHT has the best energy absorption performance. The influence of the height, direction and number of the ribs on the energy absorption performance of the hybrid cross section tubes is also discussed in this paper. The hybrid cross-section tubes could get the best energy absorption performance when the direction and height of the ribs were appropriate. And the energy absorption performance could be further improved by increasing the number of the ribs to compose the multi-cell hybrid cross section tube. The results also showed that the multi-cell hybrid cross section tube is more stable than the traditional multi cell tube under oblique loads. This will promote the application of multi-cell tubes in vehicles.