Adaptive control of structures under dynamic excitation using magnetorheological dampers: an improved clipped-optimal control algorithm

Abstract

This paper investigates the performance of magnetorheological (MR) dampers to mitigate the effect of earthquake loading on civil engineering structures. MR dampers are semi-active fluid dampers containing an MR fluid. They can generate large controllable damping forces by tuning the magnetic field applied to the fluid, which changes its viscosity. Their fast response time and low electric power requirements make them attractive for potential applications in earthquake engineering. In this study the behavior of a prototype MR damper was simulated computationally using the Bouc-Wen model. A new clipped-optimal control strategy, the improved clipped-optimal algorithm (ICA) control model, was developed and aims to reduce the acceleration response of a structure. It was implemented for a scaled three-story building in Simulink. The structural response to seven earthquakes was simulated and compared with two other established control algorithms as well as passive damping. The ICA control algorithm generated the largest reduction in acceleration and displacement response while keeping low the electric power requirements and the force generated by the damper.