Seismic behavior of self-centering beam-to-column connections with top-and-seat angles under mainshock-aftershock sequences

To investigate the seismic behavior of self-centering beam-to-column connections with top-and-seat angles under mainshock-aftershock sequences, continuous pseudo static tests on an experimental specimen were conducted. The hysteretic performance, bearing and energy dissipation capacities, initial rotational stiffness, residual deformation, and strand tension of the specimen were analyzed, respectively. The seismic performance of a semi-rigid connection with top-and-seat angles was compared with that of the self-centering connection using the method of finite element simulation. It was shown that plastic deformation is only found in the angles of the specimen, which indicates that the connection has damage controllability under mainshock-aftershock sequences. Compared with the single main shock, the hysteretic performance, energy dissipation capacity, and initial rotational stiffness of the connection are significantly reduced under the action of mainshock-aftershock sequences, while the tension of steel strands is less affected. The higher the main shock intensity is, the smaller the bearing capacity of the connection is under the aftershock. Compared with semi-rigid connections with top-and-seat angles, the self-centering connection has better seismic performance whether under the action of a single main shock or mainshock-aftershock sequences. © 2022, Editorial Office of Journal of Vibration and Shock. All right reserved.