Experimental investigation of aluminum alloy circular hollow section columns

This paper presents an experimental investigation of aluminum alloy circular hollow sections subjected to pure axial compression between fixed ends. The specimens were fabricated using 6063-T5 and 6061-T6 heat-treated aluminum alloy. The test program included 29 column tests which were separated into 4 test series of different type of aluminum alloy and cross-section geometry. Each test series contained at least 5 columns with both ends transversely welded to aluminum end plates using the Tungsten Inert Gas welding method, and 2 columns without welding of end plates. Hence, the effects of welding on aluminum alloy columns could be investigated. The specimen length ranged from 300 to 3000 mm in order to obtain a column curve for each test series. The observed failure modes for the column tests include yielding, overall buckling, and material yielding in the heat-affected zone. The test strengths were compared with the design strengths predicted by the American, Australian/New Zealand and European specifications for aluminum structures. The purpose of this paper is to present the test results of aluminum alloy circular hollow section columns with and without transverse welds, and to check the accuracy of the design rules in the current specifications.