Seismic Response Assessment of high rise RC building with Lead Rubber bearing base isolator on different soil types

In this paper, the effect of base isolator on the seismic response demands of ۱۲ story reinforced concrete buildings with moment resistant frame which are designed for soil types II and III according to fourth edition of Iran seismic code (۲۸۰۰) is investigated. The nonlinear time-history analysis is carried out on two buildings with different soil types in two states with and without base isolator under ۷ near field earthquakes which are scaled for two performance levels of life safety and collapse prevention. The seismic responses with respects to base shears and inter-story drifts are compared according to the installation of LRB isolation systems in the frame building. The main function of the base LRB isolator is to extend the period of structural vibration by increasing lateral flexibility in the frame structure, and thus ground accelerations transferred into the superstructure can dramatically decrease. Therefore, Base isolation system is able to achieve notable mitigation in the base shear. In addition, they make a significant contribution to reducing inter-story drifts distributed over the upper floors.In this paper, the effect of base isolator on the seismic response demands of ۱۲ story reinforced concrete buildings with moment resistant frame which are designed for soil types II and III according to fourth edition of Iran seismic code (۲۸۰۰) is investigated. The nonlinear time-history analysis is carried out on two buildings with different soil types in two states with and without base isolator under ۷ near field earthquakes which are scaled for two performance levels of life safety and collapse prevention. The seismic responses with respects to base shears and inter-story drifts are compared according to the installation of LRB isolation systems in the frame building. The main function of the base LRB isolator is to extend the period of structural vibration by increasing lateral flexibility in the frame structure, and thus ground accelerations transferred into the superstructure can dramatically decrease. Therefore, Base isolation system is able to achieve notable mitigation in the base shear. In addition, they make a significant contribution to reducing inter-story drifts distributed over the upper floors.

کلیدواژه ها:

Base isolator ، Existing reinforced concrete building ، time-history ، ETABS۲۰۱۵ ، ead-rubber bearing (LRB)