Seismically isolated buildings have low redundancy against extreme ground motions. The safety margin of seismic isolated buildings is evaluated in this report and, their design is based on the general design criteria for extremely rare ground motions using the incremental time history response analysis. The superstructure is analyzed with a moment frame model and is compared with a shear wall frame model aiming to improve the redundancy and the safety margin. In addition, time history response analyses are performed for long-period ground motions to compare the seismic performance of both models.
