Behaviour of high strength rectangular concrete-filled steel hollow section columns under eccentric loading

This paper presents an experimental study on the behaviour of 12 high strength rectangular concrete-filled steel hollow section columns subjected to eccentric loading. The primary test parameters were the cross-sectional aspect ratio, slenderness and load eccentricity. The specimens with cross-sectional aspect ratios of 1.0, 1.5 and 2.0 were fabricated from high strength materials (f(y) = 550 MPa; f(cu) = 70.8 and 82.1 MPa). The slenderness ratios of the specimens were 20 and 50, while the load eccentricity ratios (e/B; e is the load eccentricity, B is the breadth of cross-section) varied between 0.17 and 0.40. Favourable ductility performance was observed for all specimens during the test. The experimental ultimate capacities of the specimens were compared with the design strengths predicted by the codes. Comparison of results showed that Eurocode 4 overestimated the ultimate capacities of the columns with a difference of 3%. ACI and AISC, on the other hand, conservatively predicted the failure loads by 11% and 25%, respectively. (C) 2004 Elsevier Ltd. All rights reserved.