Stability bearing capacity of 6082-T6 aluminum alloy columns with box-type and L-type sections under eccentric compression

Experimental studies of 29 pin-ended columns eccentrically compressed around minor axis or major axis, including 13 box-type and 16 L-type, extruded from 6082-T6 aluminum alloy, were performed in order to obtain the buckling behavior, stability bearing capacity and deformation preformation of specimens. A finite element (FE) model of aluminum alloy column under eccentric compression was conducted by using finite element analysis software ABAQUS, and the simulation results were verified with experimental results of 29 columns. A parametric study of 1 908 columns with different cross section dimensions, normalized slenderness ratios, eccentric directions and eccentricity ratios, was performed using the FE model. Finally, based on the experimental data and the results of the parametric study, a revised interaction expression recommended by Chinese code for design of aluminum structures to predict the stability bearing capacity of 6082-T6 aluminum alloy specimens loaded by eccentric compression was proposed. It can be concluded that all the box-type aluminum alloy specimens fail mainly by overall buckling around the minor axis; the L-type specimens around minor axis of bending fail by overall flexural buckling in the minor axis plane. As for L-type specimens around major axis of bending, the short specimens (λ̄≤1.0) fail by flexural-torsional bucking and the long specimens (λ̄>1.0) fail by overall buckling around the minor axis; the FE model proposed by this paper can well predict the stability bearing capacity, the deformation characteristic and failure mode for aluminum alloy columns under eccentric compression and the revised interaction expression can be applied to doubly symmetric box-type cross section and mono-symmetrical L-type cross section columns under eccentric compression, which can provide a reference for the practical engineering application of 6082-T6 aluminum alloy members.