Mitigation of seismic responses on building structures using MR dampers with Lyapunov-based control

As losses of human lives and damages to buildings frequently occur during earthquake periods, it is crucial to mitigate structural vibrations. This paper describes the development of a Lyapunov-based control approach for magnetorheological (MR) dampers integrated in building structures to suppress quake-induced vibrations. In this work, MR dampers are used as semi-active devices, taking the advantages of the fail-safe operation and low power consumption. The control of MR dampers is, however, hindered by their hysteretic force-velocity responses and usually leads to indirect strategies compromising controllability and performance. To enhance the system performance, a Lyapunov-based controller is proposed here for direct control of the supply currents to the dampers for a multi-storey building. The dampers are configured in a differential mode to counteract the force-offset problem from the use of a single damper. The effectiveness of the proposed technique is verified, in simulations, by using a building model subject to quake-like excitations.