Resistance of steel and composite connections under combined axial force and bending including group effects: analytical procedures and comparison with laboratory tests

The paper presents some different developments performed in the last years at the University of Liège. In particular, complete component-based analytical procedures to predict the resistance of steel bolted connections subjected to combined bending moments and axial forces (M-N interaction) are introduced and commented. These analytical procedures consider so-called “group effects” between successive bolt-rows and cover possible ductile or brittle connection responses. Then they are extended to composite steel-concrete connections. In a second part, the analytical predictions are compared to available test data. The correlation between the experimentally measured resistances and those provided by the analytical procedures may be considered as close. Finally, the recommendations in terms of M-N interactions provided by Eurocode 3 are critically analysed.