Semi-active Control for Seismic Vibration Mitigation of Building System with Magnetorheological Damping Device

Semi-active control is considered to be very interesting in view of its similarity with the active control, however, requiring significantly lesser control-effort/input. Indeed, semi-active control strategies have been used quite widely in many vibration control applications over the past years. In the present study, a magnetorheological (MR) damper is taken as the damping device, which is used to produce the control force (through modulating its damping coefficient with the help of an external input voltage) in the semi-active framework to mitigate seismic vibration. The MR damper is well-known for its mechanical simplicity, lower power consumption, and large force capacity. The Bouc–Wen hysteresis model is taken into account for understanding the mechanical behaviour of MR damper and to calculate the control force. The widely used control strategy, viz. linear quadratic Gaussian (LQG) control, is incorporated in this semi-active control problem to generate the desired control force. The seismic vibration may cause considerable damage to a structure. In the present investigation, a three-storey building structure is considered for the demonstration of control-performance. It is observed that the semi-active control strategy has been able to perform quite satisfactorily (in mitigating the seismic vibration) with quite insignificant control-effort (in terms of supplying the electrical voltage of an insignificant range from 0 to 5 V).