Behaviour and design of prefabricated CFST stub columns with PCC connections under compression

This paper investigates the compressive behaviour of prefabricated concrete-filled steel tube (CFST) columns with prefabricated column–column (PCC) connections. The innovative PCC connections are designed using conventional structural bolts instead of expensive blind bolts to connect two prefabricated CFST columns, simplifying the construction process and rendering the construction cost-effective. The compressive behaviour of prefabricated CFST columns with or without PCC connections has been investigated numerically. Parametric studies have been conducted to investigate the effect of different parameters of PCC connections, including connection configurations, horizontal and vertical stiffeners of connections, diameter of the coupling bolt, steel tube thickness, yield strength of steel tube, and compression strength of concrete, on the compressive behaviour of CFST columns with PCC connections. The prefabricated CSFT columns with the developed PCC connections are able to achieve similar compressive strengths that are achieved by the CFST columns without connections. Therefore, the developed PCC connections can be used to construct prefabricated CFST columns for the prefabricated steel–concrete composite structures.