Experimental behaviour of high strength steel end-plate connections

The use of high strength steel in construction has recently provided some challenges to structural engineers. One such challenge is to minimise the cross-section dimensions as the material provides higher strength, which brings great economic benefits. However, high strength steels exhibit high yield ratios and limited deformation capacity when compared to mild steel grades. This behaviour can be particularly important when structures are designed for abnormal loading conditions that produce inelastic deformations. In this situation, both members and connections have to develop sufficient ductility. The connections between members, in particular, are the regions where the material is exposed to higher deformation demands. To address these topics, an experimental investigation was undertaken of moment connections with end-plates made up of the high strength steel S690. The major contributions of this study are (i) the characterisation of the nonlinear behaviour, (ii) the validation of current Eurocode 3 specifications and (iii) the ductility analysis of high strength steel moment connections. The test results show that the tested connections satisfy the current design provisions for stiffness and resistance and achieve reasonable rotation demands.