Review on Configurations of Concrete-filled Steel Tubular (CFST) Special-shaped Columns and Corresponding Beam-Column Joints

To solve the problems of insufficient structural innovation of concrete-filled steel tubular (CFST) special-shaped columns and corresponding beam-column joints, the process of development and improvement of the special-shaped column was taken as the research background, and the advantages CFST special-shaped column were pointed out. According to the two ideas of strengthening the restraint effect that the external steel tube applied to internal concrete, and increasing the stability of steel plates inside column limb unit, the CFST special-shaped columns were divided into 4 types with binding bars or stiffener ribs, multi-cell, and lacing members, and then the structural improvements of the 3 types of special-shaped columns were summarized. According to the relative position between the force transfer member and the steel tube of the column limb, the joints between the CFST special-shaped columns and beams were divided into 2 types with the force transfer member in the steel tube, and the force transfer component outside the steel tube. Moreover, the deficiencies of the CFST special-shaped column and the corresponding beam-column joint were analyzed, and that the key problems need to be further investigated was addressed.