DAMAGE EVALUATION METHOD FOR U-SHAPED STEEL DAMPERS BASED ON THE RECORDED ORBITS OF BASE-ISOLATED STORIES

Abstract

U-shaped steel damper is a type of commonly-used damping device for seismically isolated structures. After earthquakes, it is necessary to quickly evaluate the damage of U-dampers to find out if they need to be replaced. However, current evaluation method can only be used when the deformation history of the U-damper is known. In this paper, a damage evaluation method based on the area covered by the recorded orbits of the base-isolated stories is proposed. The damage of the damper during aftershocks is proved to be small enough to be ignored. The conclusions of this paper are checked against experimental data.