Mixed force and displacement control for base-isolation bearings in RTHS

Abstract

This study presents a real-time hybrid simulation of a base-isolated building. In this study, the base isolation layer is experimentally tested while the entire structure is computationally simulated. To impose the earthquake induced lateral displacement as well as the vertical gravitational force, a mixed force and displacement control strategy is developed and implemented in the experimental system. The mixed force and displacement control strategy in this study is a decentralized approach that consists of a loop shaping and the conventional PID controllers. Following a thorough experimental verification of the mixed control, hybrid simulation of a base isolated building was performed using a series of recorded earthquake ground motions. The experimental results showed that the mixed control provided accurate loading in both lateral and vertical directions. This study presents the implementation of the mixed force and displacement control as well as the results in real-time hybrid simulation.