Buckling behavior and design of concentrically loaded T-section aluminum alloy columns

Abstract

Tees are utilized as chord members in a number of arrangements of aluminum alloy trusses. The purpose of this study is to investigate the buckling behavior and design methods of concentrically loaded T-section aluminum alloy columns. Using column tests and finite element analysis, this study analyzed the buckling modes and ultimate strengths of high-strength aluminum alloy T-columns under axial compression and validated the numerical model against the experimental results. Comparisons with the current Eurocode 9 and Direct Strength Method (DSM) design rules were also conducted. Fixed- and pin-ended columns exhibit a quite different buckling behavior. The failure modes of flexural buckling about the two principal axes could be treated with sufficient safety and accuracy using the column design rules in Eurocode 9 and DSM. The effects of the effective centroid shift due to the local buckling of slender parts could be ignored. The Eurocode 9 and DSM leads to inaccurate and conservative results for fixed-ended columns failing by local-torsional buckling and flexural–torsional buckling. The paper recommends suggestions based on the DSM approach that improve the design strength predictions for aluminum alloy T-section columns.