Behaviour and Design of Innovative Connections of Prefabricated CFST Columns under Tension

Abstract

This paper investigates the tensile behaviour of prefabricated concrete-filled steel tube (PCFST) columns with bolted connections. Innovative bolted column-column (BCC) connections are developed using standard structural bolts to simplify the construction process for the connection of two PCFST columns, especially for the corner, edge, and interior columns. The behaviour of BCC connections in PCFST columns under tension has been investigated, adopting the finite element (FE) modelling approach. Parametric studies are carried out to understand the influence of bolt arrangements (TB = 4, 6, 7, 8), base plate thickness (tbp = 8, 10, 14, and 18 mm), bolt diameters (db = 16, 18, 20, 24 mm), vertical stiffeners (ths = 4, 6, 8, 10 mm), horizontal stiffeners (ths = 10, 12, 13, 15 mm), and yield strength of steel tube (fy,t = 380, 450, and 550 MPa) on the behaviour of PCFST columns with developed BCC connections. The results show that the PCFST columns with the developed BCC connections can attain sufficient tensile strength and satisfy the tensile strength requirements recommended in AS5100 and the robustness requirements in AS1170. The outcome of this paper will be useful to practising structural engineers to design prefabricated CFST columns with BCC connections under tension.