Mechanical characteristics of a novel variable friction hybrid self-centering damper

Abstract

A novel variable friction hybrid self-centering damper (VFHSCD) with significant self-centering and hysteretic energy-dissipating performance is proposed for resilient structures. This VFHSCD is composed of a novel variable friction self-centering device and an auxiliary restoring system, which is desired to alleviate the conflicting problem in designing the self-centering and friction energy dissipation performance of the existing variable friction self-centering dampers. The force-displacement relationship of VFHSCD is studied by theoretical and experimental methods first, and the self-centering and hysteretic energy-dissipating performances of the damper are then analyzed. The results show that the theoretical model of the force-displacement relationship of the damper agrees well with experimental results and presents typical flag-shaped self-centering characteristics and strong hysteretic energy dissipation performance. By using this theoretical force-displacement relationship, the effects of friction coefficient and inclination angle of the friction slopes, and the stiffness ratio and the pre-pressure ratio of the auxiliary restoring device to the transverse compression spring on the self-centering and damping performance of the VFHSCD are investigated. The results show that the VFHSCD can be optimally designed to obtain significant energy-dissipating capacity without the cost of weakening significantly its self-centering capacity.