Evaluating the Effect of Using Lead Rubber Seismic Isolator System and Friction Pendulum System with Different Periods in Improving the Seismic Behavior of Steel Framed Buildings

AbstractIn the present study, the evaluation of the seismic performance of steel framed buildings on two types of seismic isolation systems under far-fault earthquakes has been investigated. The isolator used are lead rubber bearing and single arc friction pendulum system. In order to compare the behavior of these isolators, the effective time period is considered as one of the most important properties of the isolator. The effective time period of the isolators is 2.5, 3.5 and 4.5. Three types of steel framed buildings with special moment resistant steel frames of 3, 7 and 12 stories are placed on these isolators. These three buildings represent low-rise, mid-rise and high-rise buildings. The effect of these two types of seismic isolators has been investigated in reducing the acceleration response and the relative displacement(drift) of the floors. The results show that the efficiency of both types of lead rubber bearing and single arc friction pendulum system decreases with the increase in the height of the building. The efficiency of the single arc friction pendulum system is 14% lower than that of the lead rubber bearing. Increasing the target natural period (decreasing the stiffness of the isolator) in reducing the response of the buildings in the lead rubber bearing has an average of 27% better performance than the single arc friction pendulum system.