Seismic behaviour of moment resisting frames with dissipative double split tee joints

Structural seismic systems with low damage connections or easily replaceable connections have received, in recent years, a growing interest from the scientific community on earthquake resistant design. Within this framework, damping devices able to dissipate the seismic input energy, reducing the seismic demands on the structural elements, are particularly interesting. In this paper, the possibility of providing the structure with damping devices by means of properly detailed beam-to-column joints is analysed. In particular, the behaviour of two different joint solutions equipped with damping devices, one of yielding type and one of friction type, are analysed and compared with that of full strength joints involving in plastic range a reduced beam section (RBS connections). Finally, the seismic performance of steel frames equipped with damping devices has been analysed by performing IDA analyses on three steel frames. All these frames have the same geometry and the same structural members, the only variation is due to the examined joint typology.