Abstract: This paper aims to study the energy absorption characteristics of CFRP double-cell tubes under axial compression. A preparation process of integrated carbon fiber multi-cell square tubes is proposed. The influence of energy absorption characteristics of multi-cell tubes with equal mass and wall thickness is explored. Finally, the energy absorption mechanism of multi-cell tube failure is analyzed by observing the failure modes of the tubes. The experimental results show that the energy absorption of CFRP single-cell tubes is higher than that of double-cell tubes. Compared with single-cell tubes, the specific energy absorption of equal-mass and equal-wall-thickness double-cell tubes decreased by 49.05% and 3.34%, respectively, which was due to the phenomenon of central crack and incomplete energy absorption in some region. Setting trigger is an effective way to reduce peak force and increase specific energy absorption. After setting trigger, peak force decreases by 26.21%~41.74%, and specific energy absorption increases by 2.52%~11.31%. Therefore, for the CFRP multi-cell square tubes, the double-cell tubes can not effectively enhance the energy absorption characteristics, and the destruction of the single-cell tubes are more stable than that of the double-cell tubes.

Key words: lightweight, single-cell tubes, double-cell tubes, axial compression