| Aluminum alloy was widely used in long-span spatial structures for its advantagessuch as the lightness, excellent performance of plastics, high strength-to-weight ratio,and corrosion-resistance. Due to its low value of the elastic modulus, the stabilitystrength of aluminum alloy structure components was predominant.Experimentalstudies and numerical studies of6082-T6aluminum alloy beam-columns wereperformed. The interaction expressions of Chinese Code and Eurocode9were verifiedand revised by test results and numerical results，which provided a reference for thepractical engineering application of6082-T6aluminum alloy members.Firstly,29pin-ended beam-columnsincluding13box-type and16L-type,extruded from6082-T6aluminum alloy, were eccentrically compressed around minoraxis or major axis in this paper. All the box-type aluminum alloy specimens wereobserved to fail mainly by overall buckling around the minor axis, and several by theinteraction of local and overall buckling at the decrease of load.The L-type specimensaround minor axis of bending failed by overall flexural buckling in the minor axis plane,and these short L-type columns withpositive eccentricity failed by the interation offlexural buckling and torsional buckingafter ultimate load. As for L-type specimensaround major axisof bending, the short specimens (1.0) failed by flexural-torsionalbucking and the long specimens (1.0) failed by overall buckling around the minoraxis.A finite element (FE) model of aluminum alloy beam-column was conducted byusing finite element analysis software ABAQUS, and all the29specimens wereanalysised by the FE model in this paper. The simulation results were verified withexperimental results of29columns. Initial geometric imperfection, eccentric direction,mesh size and the thickness of endplatewhich influenced simulation results wereanalyzed. It can be concluded that the FE model proposed by this paper can well predictthe stability bearing capacity, the failure mode and the deformation characteristic of6082-T6aluminum alloy beam-columns; Mesh size and thickness of end plate hadnegligible influence on FE results; the ultimate load was not sensitive to thechange ofintial imperfection if the amplitude of that was less than1/1000of effectivelength.A parametric study of1908columns with different cross section dimension,regularized slenderness ratio, eccentric direction and eccentricity ratio, was performedusing the FE model.Based on the experimental data and theresults of the parametricstudy, Chinese code and Eurocode9were verified that they can be applied to doublysymmetric Box-type cross section and mono-symmetrical L-type cross sectionbeam-columns. Two kinds of revised interaction expression recommended by Chinese Code and Eurocode9were proposed and compared with Chinese Code and Eurocode9.It can be concluded thatthe two revised interaction expression were more accurate thanChinese Code and Eurocode9. |
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