Robustness of a tuned viscous mass damper (TVMD) controlled system

A tuned viscous mass damper (TVMD) is a novel type of vibration absorber which exhibits outstanding vibration control performance. In this study, an experiment was conducted to investigate the robustness of a TVMD for the vibration control of a typical single degree of freedom (SDOF) structural system. To that end, a new eddy-current TVMD (EC-TVMD) was developed as a representative TVMD device. The TVMD-controlled SDOF system was investigated using a series of shaking table tests. The influence of variations in stiffness of the primary structure and TVMD damping (including damping amplitude and damping nonlinearity) was assessed. The variation in TVMD damping exerted a smaller influence on control performance than the variation in primary structure stiffness. The robustness of TVMD control was enhanced by increasing the inertance-to-mass ratio. Parametric analyses using a numerical model further confirmed the experimental observations, and indicated that a TVMD exhibits improved robustness compared with a conventional tuned mass damper (TMD) which is sensitive to the detuning effect. The vibration control mechanism and robustness characteristics of the TVMD were further revealed by a Kelvin-Voigt model. Finally, the influence of damping nonlinearity was verified by the nonlinear time history analysis of a finite element model of the test structure. The results indicate that damping nonlinearity has limited influence on the control of a TVMD with nonlinear damping as long as this TVMD has the same peak displacement amplification ratio as the optimal linear design.