Seismic analysis of a reinforced concrete building isolated by high damping rubber bearings using deformation history integral type model

The base-isolation system is a very effective technology for earthquake resistance. Nevertheless, it is adverse to the horizontal displacement control of isolation layer and less efficient in reducing the seismic response of the superstructure on a soft soil. The high damping rubber bearings can provide large hysteretic damping and show hardening effect at high shear strains. To explore the applicability of high damping rubber bearings (HDRBs) and the effect of their characteristics on the seismic responses of the structures on soft soils, a six-story reinforced concrete (RC) building isolated by HDRBs on a soft soil is modeled in SAP2000. By applying deformation history integral type model (DHI model) which can accurately simulate the characteristics of HDRBs and traditional Bouc-Wen model which ignores the hardening effect and high energy dissipation capacity of HDRBs at large shear strains to the bearings separately, seismic responses considering and neglecting the hardening effect and high energy dissipation capacity of HDRBs at large shear strains are investigated. The comparison of the two models shows that the characteristics of HDRBs can effectively reduce the displacement of the isolation layer under extremely strong earthquakes and are conducive to the safety of superstructure under limited earthquake intensities.