转动摩擦-弯曲屈服两级耗能阻尼器疲劳性能

This paper proposed a combined rotational-friction (RF) and flexural-yielding metallic (FYM) damper, which can be used for precast beam-column connections. It was a two-stage energy-dissipating structure composed of rotational friction hinge and flexural yielding channel steels. According to theoretical analysis of RFFYM dampers, the two-stage energy dissipation mechanism was presented. The RF hinge can dissipate energy by rotating friction under small deformation (small and medium earthquake), and the FYM damper yields to dissipate energy under large deformation (rare earthquake or very-rare earthquake). The experiments on energy dissipation capacity of single RF hinge and fatigue performance of RF-FYM damper were carried out. The fatigue failure mode of RF-FYM damper was flexural tensile failure of the channel steels flange. The hysteretic curve of the RF hinge exhibited a typical 'rectangular' shape. As for the RF-YFM damper, the fatigue hysteresis curve exhibited 'spindle' shape at the initial stage and flexural yielding occurred in channel steels. It can be concluded that the hysteretic energy dissipation performance of the friction damper is stable under small deformation, and can meet the seismic requirements of "no damage under small and medium earthquakes"; Under large deformation (rare earthquake), the FYM damper yields and consumes energy, eventually causing weld fatigue failure. This RF-FYM damper can meet the seismic design goal of "no damage under small and medium earthquakes, and repairable under large earthquakes".