Experimental behaviour of friction T-stub beam-to-column joints under cyclic loads

Eurocode 8 has introduced the possibility of adopting partial-strength joints for seismic-resistant MR frames, provided it is demonstrated that connections perform adequately under cyclic loads. A programme of experiments devoted to investigating the cyclic behaviour of traditional joint details has recently been carried out by the authors. Within this programme, the analysis of the results obtained has revealed that even though connections designed to dissipate the seismic energy in bolted components can provide significant advantages because they are easy to repair after a destructive seismic event, they possess reduced dissipation capacity when compared with RBS connections and traditional full-strength joints. An advanced approach aimed at enhancing the hysteretic behaviour of double split tee (DST) joints and the ambitious goal of preventing joint damage is presented here. The system proposed is based on the idea of using friction dampers within the components of beam-to-column joints. A preliminary set of prototypes has been tested experimentally and the performances of joints under cyclic loading conditions have been compared with those of traditional joint details. The experimental work was carried out at the Materials