Vibration control technology aims at reducing the dynamic responses of engineering structures when they are subjected to the external excitations. By providing supplemental stiffness or damping for the structures, most control devices have been proved to be effective in numerical analyses and practical applications (Spencer and Nagarajaiah, 2003),and many vibration control devices have been implemented in engineering structures. For example, viscous dampers were installed in the Golden Gate Bridge for seismic retrofit (Rodriguez and Ingham, 1995); active mass damper systems were applied in the Kyobashi Center (Kobori et al., 1991) and the Nanjing Tower (Cao et al., 1998).