Assessing the behavior of column-splice connections between CFSTS in axial tension

Increasing the sustainability of construction materials is a key goal in the construction industry. As the demand for high-rise residential structures grows, new more efficient methods of achieving sustainability are required. Rendering larger structures demountable to enable the re-use of steel structural members is one solution. The aim of this study was to investigate and assess the behavior of blind bolted column-column connections between concrete filled steel tubes in axial tension. The investigation aimed to address the need for accurate design guidelines for tensile members in the composite design standards such as Eurocode 4 and encourage the use of columncolumn connections in large-scale demountable structures. A numerical investigation of the blind bolted column-column connection has been performed using ABAQUS. The model consisted of two concrete filled square hollow steel sections connected using sleeve plates welded to the top tube only, as well as 16 M20 Lindapter Hollobolts connecting the tubes. The numerical investigation revealed that the sections tested conformed with AS1170.1 regarding columns in tension. Results of the numerical investigation have been compared against experimental results for a continuous CFST and it was found that the connections performed better in tension. The parametric analysis revealed no dependence of the shape of force-displacement relationships on diameter to thickness ratio, concrete compressive strength or yield stress.