This paper shows application of viscous mass damper with restriction mechanism to base-isolated structures, and its effectiveness. Damper force restriction mechanism was modeled by complex stiffness model and it shows the response characteristic of this system based on equivalent linearization method. The effectiveness of this system was examined by non-linear time history response analysis using seismic waves. These results confirmed that it is possible to apply large added mass to base-isolated structures, and that large displacement reduction effect was achieved by using damper force restriction mechanism. At this time, damper force restriction mechanism clearly showed that damping force can be controlled.
