Closed Form Prediction of the Deformation Capacity of Bolted T‐Stubs

Abstract
The component method currently codified in Eurocode 3 Part 1‐8, enables the simplified analytical modelling of the joint behaviour by decomposing connections into basic components. However, this method shows limitations in accurately predicting the actual collapse mechanisms and the deformation capacity. Within this framework, this study addresses these limitations by focusing on the T‐stub component, proposing a unified and simplified methodology to evaluate its ultimate resistance and deformation capacity. Building upon recent advancements, a refined classification of failure modes is adopted, introducing a novel intermediate failure mechanism (MEC‐1.2) and incorporating a more accurate estimation of the contact force location. Closed‐form expressions for strength and ductility are derived for each failure mode, drawing from and extending existing models. These formulations are validated through an extensive parametric analysis involving 146 T‐stub configurations. Results demonstrate satisfactory agreement, with average predictive errors within 10% and Coefficients of Variation below 0.15. This work contributes with a practical and reliable tool to the evaluation of the T‐stub performance and lays the foundation for future developments toward joint modelling with the component method.