Previous studies have suggested that rocking vibration accompanied with foundation uplift motion might reduce the seismic damage to buildings subjected to severe earthquake motions. Based on this knowledge, the authors have proposed the uplift rocking system that makes use of the uplift yielding mechanism of specially designed flexing base plates, and showed that the yielding base plates work as hysteretic dampers. In this paper, the authors examine the hysteretic characteristics and cumulative plastic deformation capacity of the yielding base plates for the uplift rocking system using the results of the statically cyclic loading tests. It is shown that the proposed calculation provides the approximate estimation of the mechanical properties of hysteretic behavior of the yielding base plates, and that the haunched base plates improve the cumulative plastic deformation capacity compared with non-haunched base plates.
