An assessment of application of the component-based method to full range behaviour of joints between steel beam to concrete filled steel tube columns under extreme loading conditions

Joints are critical members that play an important role in controlling the disproportionate collapse process of structures under extreme loading conditions. In Eurocode 3 Part 1–8, reference is made to the "component-based method” for the design of structural joints in building frames. Compared with the application of this method to beam-to-column joints for H-sections, information on the components of steel beam-concrete filled steel tube (CFST) joints is much less readily available. This paper presents a comprehensive review of the calculation methods for the key quantities of the full force-displacement relationships, including resistance and deformation capacity, for all the connection components in different types of steel beam to CFST column joints. The accuracy of these relationships is assessed in the context of their applications as input data to the component-based method to calculate the full load range behaviour of complete steel beam-CFST column joints. The results show that there exist methods that can be used to accurately calculate the resistance of all the components, except for the component of extended Hollo-bolt to CFST column in tension. However, there is no existing method that can be used to accurately calculate deformation capacities of the joint components. Furthermore, this review indicates that improvements are needed to enable steel beam to CFST column joints to possess sufficient rotation capacities so as to allow the structures to control disproportionate collapse under extreme loading conditions.