Hysteresis based vibration control of base-isolated structures

Abstract

An active control strategy for base-isolated structures is proposed in this work. The key idea comes from the observation that passive base isolation systems are hysteretic. Thus, an hysteresis based vibration control is designed in a way that the control force is smooth and limited by a prescribed bound. A model of a three-story building is used to study and compare the efficacy of a passive pure friction damper alone, with the addition of the proposed active control. We introduce a rate limiter to the actuator to simulate its limited speed capacity, present in every physical actuator. Simulations demonstrate that our active control strategy significantly reduces base displacements and shears without an increase in drift or accelerations.