Remarks on the use of EC3-Annex J for the prediction of aluminium joint behaviour

A critical examination of the possibility to apply EC3-Annex J component method for the prediction of the ultimate resistance of aluminium T-stub joints is presented in this paper. Based upon numerical results, the need to develop alternative simplified procedures is firstly stated. This is essentially due to the fact that in case of aluminium alloy structural components the material strain hardening and ductility may strongly influence the behaviour of the system, especially at the collapse limit state. Therefore, the codified approach for steel appears to be inadequate to be simply extended to aluminium joints, being unable to predict the collapse mechanism type, as well as to account for the beneficial effect of hardening. On the basis of a wide parametric analysis, a correction procedure is proposed in this paper. It allows such effects to be properly accounted for at least when the collapse mechanism type 1 occurs - namely in case of strong bolt-weak T-stub flange combination - through a balancing factor to be used in the same simplified relationship proposed by EC3-Annex J. Finally, the variation of this factor with both material strain hardening and ductility is provided.