| Structural control techniques have been extensively explored in the past decades, contributing to substantial safety improvements. Still, recent experience shows that the property damage resulting from even a moderate earthquake is significant. This dissertation studies the design and development of a new mechanical vibration absorber (i.e., gyromass damper or GMD) that uses gear assemblies to generate acceleration-proportional resisting forces. Similar to dynamic vibration absorbers such as tuned mass dampers, GMDs allow the introduction of control forces that are caused by inertial forces. However, unlike tuned mass dampers, they do not require a large additional physical mass. With the aim of incorporating GMDs in real structures, sample configurations are presented that are simple to build, and the effectiveness, robustness, and limitations of these devices for linear systems are investigated. This dissertation has two main foci regarding the application of GMDs for passive control of structures. The first is to improve the current state of the literature by characterizing and modelling the dynamic behaviour of GMDs. While the second is the application of real-time hybrid simulation method as a dynamic testing tool to experimentally examine the effects of GMDs on the performance of SDOF systems. The numerical simulations and experimental results show that GMDs consistently enhances the performance of SDOF systems and it is possible to improve the efficiency of the control system further by employing braces or energy dissipation devices in parallel with the GMD. |
