Towards a consistent design approach for steel joints under generalized loading

The behaviour of steel joints is complex and requires the proper consideration of a multitude of phenomena, ranging from material non-linearity (plasticity, strain-hardening), non-linear contact and slip, geometrical non-linearity (local instability) to residual stress conditions, and complicated geometrical configurations. The component method is widely accepted as the practical approach in predicting the behaviour of steel joints and it provides detailed procedures to evaluate the strength and initial stiffness of steel joints, as specified in Eurocode 3.Current safety concerns for steel structures require that steel joints are designed to perform adequately under a wider range of loading conditions: besides standard static loading conditions, fire and seismic loading must often be considered. In addition, robustness requirements impose that joints present a minimum level of resistance for any arbitrary loading. Predicting the 3-D behaviour of steel joints under arbitrary loading must thus be achieved in a practical way.This paper presents the results of a series of experimental developments that attempt to contribute to the knowledge of the 3D behaviour of steel joints, under static and dynamic conditions, and to discuss a possible framework for these general conditions that is in line with the principles of the component method.