cross section crash boxes

Figure 3.14. Deformed shape of 1T1L and 2l2T steel-CFRP square tubes.
(Source: Bambach, et al. 2009)
Jensen and colleagues investigated experimentally and numerically the
deformation mode transition from progressive to global buckling of 6060T6 Al square
tubes, (Jensen, et al. 2005, Jensen, et al. 2004). Global buckling was found to absorb
less energy than progressive buckling. The transition from progressive folding to global
buckling occurred after a certain time (Figure 3.16). It was also noted that the transition
was delayed at increasing impact velocities due to the inertia forces.
The effect of trigger on the energy absorption capacity of square Al tubes with
full and half dent shapes on the surface were also investigated (Lee, et al. 1999). Half
and full multiple dent tubes showed lower energy absorption than the tubes without
dent.
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