Extending Component‐Based Models to Full‐Range Behaviour of Steel Joints

Abstract
Component‐based spring models developed according to the Component Method provide a practical alternative to advanced finite element (FE) models for predicting the behaviour of beam‐to‐column joints. However, inherent limitations of the EC3 analytical approach lead to joint characterisations that neglect key response features, including group effects, realistic shear distribution within the column web panel zone, and component stress interactions. Moreover, EC3 predictions are generally restricted to joint initial stiffness and plastic resistance, omitting strain‐hardening effects and ductility capacity, which are essential for robustness‐oriented structural design. This study extends a previously proposed Generalised Component‐Based Model (GCBM) by incorporating post‐plastic behaviour at the component level, including strain hardening and post‐buckling response. The enhanced model enables prediction of joint ultimate resistance and rotation capacity. Validation against experimental and numerical results demonstrates satisfactory accuracy in reproducing the full‐range response of beam‐to‐column joints subjected to bending and combined bending–axial loading. The proposed model provides a reliable and computationally efficient tool for simulating joint behaviour up to failure.