Seismic Performance of Self-Centering Moment Resisting Connections with Bottom Flange Friction Devices (BFFD)

Recently self-centric moment resisting connections have been introduced as alternative welded moment resisting connections. These connections are comparing of post tensioned strands and energy dissipater parts. In construction of connection the high strength strands have been post tensioned and because of the post tensioned forces during earthquake period, the structure returns to the pre earthquake condition with less damage in comparison with usual moment resisting structures. One of the energy dissipater devices of these systems isbottom flange friction device (BFFD). In this paper, firstly the behavior of connection in 6 story 4 bay building have been verified with literature which OPENSEES software is used for this purpose. Then nonlinear dynamic and static analyses have been performed. In this study the number of post-tensioned strands, optimum force of strands, arrangement of strands in stories and shape memory alloy materials effect on strand’s behavior have been evaluated. The results shows increment of strands to 40 improves the behavior of connection and the increasing of post-tensioned forces up to determined value causes the improvement of connection behavior.