Seismic behavior evaluation of friction-bearing type connection with slit dampers

Abstract

Ductility-based design for structural collapse prevention may not be sufficient for the higher performance demand of minimizing the time and cost for function recovery. A friction-bearing type connection with slit dampers was introduced to the beam system at the beam end, and it followed the characteristics of the damage-controlled type connection. The design considerations for the proposed connection were presented and the experimental investigation on the cyclic behavior of the designed specimens was conducted. The results demonstrated that the designed connection exhibited a stable and full hysteresis behavior under cyclic loading, without obvious performance degradation. With a longer slotted hole in the slit damper, the friction-slipping behavior was obvious and the maximum rotation angle could be up to 0.05 rad, while the bearing capacity was enhanced with a shorter slotted hole. The friction-slipping behavior also improved the stress development of main structural members and enhanced the ductile behavior. The proposed connection could develop two-stage energy dissipation behavior, and the frictional slippage was greatly helpful for dissipating energy. The damage concentration was achieved, and the energy dissipated by the proposed connection accounted for more than 75 % of the total dissipated energy. The the inelastic deformation was mainly concentrated in the slit damper, while the beam and the column remained elastic, greatly improving the seismic resilience.