Evaluation of the lever-type active tuned mass damper for structures

Abstract

The lever-type active tuned mass damper (LT-ATMD) is proposed in this paper to achieve a control system with high effectiveness, in which the static and dynamic stretching of the spring may be freely adjusted. Employing the formulated dynamic magnification factors of the LT-ATMD structure system, the evaluation is conducted on the control performance of the LT-ATMD (including the LT-ATMD stroke). The results indicate that the LT-ATMD with the actuator set at the mass block can practically reach the same optimum damping ratio, optimum tuning frequency ratio, effectiveness, and stroke as the ATMD. The LT-ATMD with the actuator set at the mass block is shown to have significantly better effectiveness than the lever-type tuned mass damper (LT-TMD, i.e. the passive counterpart of the LT-ATMD). More importantly, the static and dynamic stretching of the spring in the LT-ATMD with the actuator set at the mass block may be freely adjusted in accordance with the practical requirements by changing the support location, while approximately maintaining the same control performance (including the same stroke). In view of this, the LT-ATMD with the actuator set at the mass block may be a better choice for suppressing the vibrations of long-span bridges, avoiding large static and dynamic stretching of the spring. Copyright © 2004 John Wiley & Sons, Ltd.