Proposal for vertical distribution of seismic design load and equivalent isolation ratio for seismically isolated buildings with multiple types of dampers: Vertical distribution of seismic design load for seismically isolated buildings corresponding to diversity of seismic isolation devices, part 2

As previously reported, we have proposed a vertical distribution of seismic design load for seismically isolated buildings (SIBs) corresponding to diversity of seismic isolation devices such as hysteretic dampers and velocity-dependent dampers. This proposed seismic design load is obtained from the relationship between response amplification caused by higher mode responses and the isolation ratio which represents structural characteristics of SIBs. In this paper, we build a concept of the equivalent isolation ratio which has applicability to various dampers in order to simplify an evaluation formula of vertical distribution of seismic design load. Moreover, an effect of the combined application of various dampers on vertical distribution of shear force coefficient of SIBs is analyzed on the basis of the equivalent isolation ratio.