[en] In EN 1994-1, design rules are given for the evaluation of the mechanical properties of structural steel-concrete composite joints (rotational stiffness, resistance and ductility) based on the component method offered in EN 1993-1-8 and adding specific components for composite joints. These rules cover only the situations for the joints subjected to shear forces and hogging moments. However, during the last decades, researches have been conducted on the behaviour of composite joints subjected to different kind of actions such as sagging bending moments, cyclic loadings, combined bending moments and axial loads, elevated temperatures etc. with the objective of improving/extending the rules presently proposed in the Eurocodes design rules. As an outcome of the Technical Committee 11 of the European Convention of Constructional Steelwork (ECCS) dedicated to the behaviour of composite structures, a publication summarising these recent developments and their main outcomes is under finalisation. Within the present paper, it is proposed to highlight these main outcomes which could be seen as proposals for future improvements of the beam-to-column provisions in Eurocodes in general and of Eurocode 4 in particular. (Author)

[en] The slim-floor building system is attractive to constructors and architects due to the integration of steel beam in the overall height of the floor, which leads to additional floor-to-floor space, used mostly in acquiring additional storeys. The concrete slab offers natural fire protection for steel beams, while the use of novel corrugated steel sheeting reduces the concrete volume, and replaces the secondary beams (for usual spans of steel structures). Currently the slim-floor solutions are applied in non-seismic regions, and there are few studies that consider continuous or semi-continuous fixing of slim-floor beams. The present study was performed with the aim to develop reliable end-plate bolted connections for slim-floor beams, capable of being applicable to buildings located in areas with seismic hazard. It is based on numerical finite element analysis, developed in two stages. In a first stage, a finite element numerical model was calibrated based on a four point bending test of a slim-floor beam. Further, a case study was analysed for the investigation of beam-to-column joints with moment resisting connections between slim-floor beams and columns. The response was investigated considering both sagging and hogging bending moment. The results are analysed in terms of moment-rotation curve characteristics and failure mechanism. (Author)