Experiments on cyclic behaviour of reusable side plate cold-formed steel semi-rigid moment-resisting connections

Eight large-scale tests are presented on cantilever side plate cold-formed steel (CFS) semi-rigid moment-resisting connections. These comprise lipped or unlipped side-plates attached to both sides of built-up tubular CFS beam and column sections by means of bolted or screwed connections. The reusability of the connections is investigated by repeating the tests with the original beam and column sections and modified connections. The predominant limit state is side plate plasticity (SPP) for all the connections except the lipped screwed connections governed by screw shear (SS) failure. The findings demonstrate that lipped side plate connections reached a higher peak moment and energy dissipation by up to 60 % and 120 %, respectively, compared with those of the unlipped connections. All the tested connections are classified as semi-rigid while the bolted connections show up to 1.9 times higher level of elastic stiffness than the screwed connections. The lipped side plate bolted connection is identified as more suitable to be considered for a reusable design. • Eight large-scale cold-formed moment resisting connections are tested. • The reusability of the connections is investigated. • The predominant limit state is side plate plasticity. • The best connection configuration is identified.