Design of hollow joints using the component method

The component method is a design approach for the characterization of the mechanical proper-
ties of structural joints. initially the component method has been developed for joints between open sections and it is referred to in Eurocode 3 Part 1.8. It allows a theoretical evaluation of the resistance, stiffness and ductility properties based on mechanical models. However, the design of joints between tubular hollow sections follows a different approach. A joint (or more precisely a joint configuration, i.e. a zone where two or more members are connected) is considered as a whole when determining its resistance(s). Existing design rules for joints between tubular hollow sections are based on simple theoretical mechanical models and they are then fitted through comparisons with experimental tests. As a consequence, their field of application is often restricted to the domain for which the rules have been validated. Under the umbrella of CIDECT, a project is being carried out to develop a unified design approach for steel joints independent of the type of section of the connected elements by extending the field of application of the “component method”. To achieve this objective, rules recommended for hollow section joints have to be “converted” into a component format. The present paper presents ways and means for the development of such a unified design approach. Components have been identified in typical hollow section joints in lattice girder structures. The paper presents also design
rules (component resistances and assembly rules) for some hollow section joints as examples.