Research advances in fiber‐reinforced concrete‐filled steel tube columns

Abstract

SummaryFiber‐reinforced concrete‐filled steel tube (CFST) adopts the microskeleton and bridging effect of fibers, thereby optimizing the confinement effect between the steel tube and concrete core while reducing the concrete core friability. This structure offers a viable solution for solving the interface disengagement and insufficient ductility problems of conventional CFSTs. For further theoretical research and engineering application, the mechanical properties of fiber‐reinforced CFSTs under different loading conditions are reviewed. The research results are summarized, and future research scopes are suggested. The literature review shows that adding fibers improves the ductility of CFSTs significantly but the bearing capacity only slightly. The bond strength between steel tube and concrete core is enhanced by fibers, and the degradation in the bond strength is simultaneously delayed. However, in existing research, the mechanical properties and design method are still inadequate. More experimental works, further theoretical analyses, and numerical simulation should be undertaken to establish the quantitative relations between the generalized fiber parameters and structural performance of CFSTs. Future research should propose a unified design theory of fiber‐reinforced CFST structures based on service performance requirements.