Generalised Component Model for Structural Steel Joints

Abstract

This paper presents a generalised component model for structural steel joints that extends the Component Method to the post-ultimate and post-fracture ranges. In this approach, a tri-linear spring model was developed for each individual component to include their post-ultimate behaviour, and a new concept of the instantaneous centre of rotation was introduced to track the changing load condition of each series of springs in a multi-spring system. The proposed generalised component model can predict the full-rangeM − θ curves of multi-spring models containing any number of deformable springs, and does not pose numerical difficulties in the post-ultimate range where some springs unload. The method is potentially applicable to all types of steel joints. The paper presents the application of the method to recent experimental tests on bolted moment end plate connections, showing good agreement over the full range of behaviour including fracture. The paper also demonstrates the application of the method to produce the backbone curve for a hysteretic model for the bolted moment end-plate connection.