Generalised Component Method-based finite element analysis of steel frames

The design-by-analysis approach lays the foundation for the next generation of structural design standards in which the strength and structural safety check are performed in a single step at system level, without recourse to a structural standard for individual member checks. However, to date, no attempt has been made towards considering the failure of joints in the structural analysis, without which the complete set of limit states cannot be accurately predicted. This paper presents a new analysis approach that incorporates macro-element joint models based on the Generalised Component Method in the FE analysis of steel frame buildings. The new analysis approach is termed Generalised Component Method-based finite-element (GCM-FE) analysis. The fundamental aspects and principles of the GCM-FE analysis approach are established in this paper, including the framework of GCM-FE analysis, the constitutive models for the connection components and the implementation of GCM-FE analysis in commercial numerical software including an automatic modelling technique. The GCM-FE joint modelling method is first validated against the experimental results of three steel beam-to-column connection types, including the bolted moment end-plate connection, top-and-seat angle connection and web angle connection. GCM-FE analysis is subsequently performed on a two-storey four-bay irregular steel frame, showing apparent advantages over the traditional analysis methods which adopt simplified joint models. The GCM-FE analysis not only provides the ultimate resistance and failure mode of the frame, but also accurately predicts the load-redistribution process inside the connections and the resultant effect on the structural framework.