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The Strength in Axial Compression of Aluminum Alloy Tube Confined Concrete Columns with a Circular Hollow Section: Experimental Results

Steel tube confined concrete (STCC) stub columns have great strength and facilitate construction. In this study, the axial compressive strength of an aluminum alloy tube confined concrete column with (ATCC-CHS) and without (ATCC) a circular hollow section was tested in laboratory experiments. The influence of concrete strength, diameter–thickness ratio and the hollow rate on the failure mode, ultimate compressive strength, strain, stiffness, constraint effects and ductility was quantified. The experiments showed that local buckling failure could be effectively delayed when the outer aluminum tube did not directly bear axial load. Columns without a circular hollow section had bearing capacities approximately 20% higher than those with a circular hollow section, though their ductility was poorer. The ultimate strength tended to increase with decreases in the hollow rate and diameter–thickness ratio. It tended to increase with increasing concrete strength, though stronger concrete also reduced ductility. The bearing capacities of the columns were calculated according to several proposed formulas and compared with the experimental results, and the proposed Teng and Attard’s formula appeared to be satisfactory.