Quasi-static axial compression of thin-walled circular metal tubes including effects of foam filling

摘要

In this paper we present some preliminary findings from a series of 33 experiments that were conducted to investigate the axial compression behaviour of very thin-walled (D/t≥50) 6060 -T5 aluminium alloy tubes both with and without a filling of polyurethane foam. The aluminium tubes were tested quasi-statically at a constant velocity of 5 mm/min. A range of tube dimensions were examined with D /t ratios varying from 50 to 200 and L/D ratios varying from 2 to 4. A variety of foam densities from 35kg/m{sup}3 to 140kg/m{sup}3 were considered for the case where D/t =98 and L/D = 2. It was found for empty tubes that at large values of D/t the ratio of F{sub}(max) /F{sub}(av). became very large and also the variability of this force ratio increased. For foam-filled tubes it was found that the foam density had to be reduced to the low value of 35 kg/m{sup}3 for there to be a negligible effect on the collapse mode of the aluminium tube. At higher foam densities a change in collapse mode from asymmetric to at least partially symmetric was observed.