LAUSR

Abstract To alleviate the complex construction process of traditional concrete filled steel tube (CFST) column-foundation connections, the anchor rebar column-foundation connection (ARCFC) has been conceived and investigated. To date, the thin-walled steel tube is recommended to be used considering it economic benefits. However, the confinement provided by the thin-walled steel tube is found to be insufficient as bulges of steel tube and concrete are observed. In this paper, carbon fiber reinforced polymer (CFRP) is adopted in the potential plastic hinge region to prevent the local buckling of steel tube. Nine specimens were designed and tested to failure under combined constant axial load and reversed cyclic lateral load. The investigated parameters are the number of CFRP layers and the diameter-to-thickness of steel tube. Experimental results revealed that bulges of steel tube and concrete were observed for ARCFCs with a diameter-to-thickness ratio of steel tube over 120. CFRP could effectively prevent the bulges of steel tube and concrete. All the ARCFCs have excellent energy dissipation capacity and the ductility coefficient is larger than 4.55. A finite element model (FEM) is developed to conduct a parametric study, based on which the sectional strength model is suggested.