Energy absorption capacity of composite thin-wall circular tubes under axial crushing with different trigger initiations

International audienceThe purpose of this study is to evaluate and compare the ability of various composite structures to dissipate the energy generated during a crash. To this end, circular composite tubes were tested in compression in order to identify their behavior and determine their absorbing capabilities using the Specific Energy Absorption (SEA) (energy absorbed per unit weight). Several composite tubular structures with different materials and architectures were tested, including hybrid composition of carbon-aramid and hybrid configuration of 0/90 UD with woven or braided fabric. Several inventive and experimental trigger systems have been tested to try and enhance the absorption capabilities of the tested structures. SEA values up to 140 kJ.kg-1 were obtained, achieving better than most instances from the literature, reaching around 80 kJ.kg-1. Specimens with 0°-oriented fibers coincidental with the direction of compression reached the highest SEA values while those with no fiber oriented in this direction performed poorly. Moreover, it has consequently been established that in quasi-static loading, a unidirectional laminate oriented at 0° and stabilized by woven plies strongly meets the expectations in terms of energy dissipation. Incidentally, an inner constrained containment is more effective in most cases, reducing the initial peak load without drastically reducing the SEA value