Semi-active Base isolation System for Buildings using MR Dampers

Due to limitations on the use of passive base isolation systems which show poor performance in near field seismic excitations or active systems which require high external power, as stand alone control devices for a range of seismic excitations, a hybrid control system that mitigates the limitations of either passive or active control systems is preferred. The present study examines the use of semi–active base isolation systems for vibration mitigation. A combination of base isolation and MR-dampers forms the control device that has been deployed as a base isolation unit in the building. A combination of GA–fuzzy based control algorithm has been proposed to be implemented as a control strategy. Scaled seismic inputs for both near and far field excitations have been used in this study on three story (base + three) building. The paper presents the analytical modeling and results obtained through numerical experiments.