Active vibration control of lightweight floor systems

Abstract

Long-span and lightweight floors are often prone to structural vibrations due to their low resonance frequency and inherent damping. They are easily excited by human walking or running and present a serviceability problem for persons working or living in these buildings. Tuned mass dampers can be used to improve the dynamic behaviour of such structures. The drawback of these passive damping systems is that they require high inertial damper masses and that the damping efficiency in transient phase is low. Especially for systems with resonance frequencies that change over time (due to an addition mass or a change of the structure or temperature dependant phenomena) the damping efficiency drops rapidly. Active controlled tuned mass damper can be used to reduce the inertial mass and improve the damping efficiency for a broad band of frequencies in transient phase. Several constraints, like the stability in closed loop, robustness and performance criteria and the maximum stroke and saturation of the actuator have to be considered when designing a controller for an active vibration control device. Different control strategies are analysed in this work and simulated using a 2nd and a 4th order system in order to analyse advantages and drawbacks.