Effective usage of high strength steel tubes: Axial compressive behavior of hybrid FRP-concrete-steel solid columns. (September 2020)

• Record Type: Journal Article
• Authors: Guo, Yong-Chang; Ye, Yu-Yi; Guan-Lin, ; Lv, Jun-Fan; Bai, Yu-Lei; Zeng, Jun-Jie
• Is Part Of: Thin-walled structures. Volume 154(2020)
• Publication Date: 2020-09
• Subjects: Fiber-reinforced polymer (FRP) -- Confinement -- Polyethylene terephthalate (PET) FRP -- Large rupture strain (LRS) FRP -- High-strength steel (HSS) -- FRP-Concrete-steel solid columns (FCSSCs); Thin-walled structures -- Periodicals; 690.1
• DOI: 10.1016/j.tws.2020.106796
• Languages: English
• ISSNs: 0263-8231

Abstract

Abstract: The novel form of hybrid columns, being fiber-reinforced polymer (FRP)-concrete-steel solid columns (FCSSCs), involves the FRP tube and the steel tube as the confining system for the concrete. The buckling of the inner steel in FCSSCs is effectively delayed by the surrounding concrete while the strength of the steel is sufficiently utilized, with it being protected by the outer FRP tube against environmental attacks. A pilot experimental program is conducted to investigate the behavior of axially loaded FCSSCs with an outer polyethylene terephthalate (PET) FRP tube. The experimental results have demonstrated that the axial load carrying capacity of an FCSSC is much larger than the total resistances of the hollow steel tube and the concrete-filled FRP tube. The test FCSSCs possess a monotonically ascending load-strain response with an excellent ductility. The comparisons between the test results and the predictions from existing models demonstrate that one existing model gives satisfactory estimations on the ultimate axial stress and strain of the confined concrete in FCSSCs, while they are incapable to accurately predict stress-strain curves of the confined concrete in FCSSCs. Highlights: An experimental study on PET FRP-concrete-high strength steel solid columns is presented. The post-yield strength of the high strength steel can be effectively utilized in FCSSCs. The FCSSCs possess a bilinear axial load-axial strain curve and an excellent ductility. The buckling of the high strength steel tubes is delayed in FCSSCs and the inner steel provides additional confinement to the concrete. The model of Lin et al. is able to predict the ultimate axial stress and the ultimate axial strain of confined concrete in FCSSCs.