Torsional crushing of foam-filled thin-walled square columns

Torsional crushing behavior of foam-filled thin-walled square columns were investigated analytically, numerically and experimentally. The lower and up per bounds on the torsional resistance of foam-filled columns were establis hed analytically. Numerical simulations were carried out and showed that th e presence of the filler changes the torsional collapse mechanism and gives rise to higher order sectional collapse modes, which results in a higher t orsional resistance. Torsional experiments were performed and results were compared to the analytical and numerical solutions with reasonably good agr eement. It was found that bonding of the foam to the walls changes the defo rmation mode by spreading deformation over the whole length. The correspond ing torsional resistance is also larger for the first 40 degrees of rotatio n. It is concluded that fitting prismatic members with the aluminum foam of a density ranging from 0.14 to 0.28 g/cm(3) can double the energy absorpti on of a given member. (C) 2001 Elsevier Science Ltd. All rights reserved.