Dual-Demand-Based Optimal Design of Lightweight Tuned Viscous Mass Damper (LwTVMD) for Seismic Response Mitigation

This study proposes a generalized type of tuned viscous mass damper (TVMD) considering dual-terminals and apparent mass amplification effect simultaneously, namely, lightweight tuned viscous mass damper (LwTVMD).

The motion control equations of the LwTVMD system are established and the closed-form optimal expressions are derived based on H₂ optimization. And a dual-demand-based lightweight design approach is proposed to implement comprehensive reduction of design parameters. The rationality and superiority of this method are verified under typical excitations.

It is concluded that the closed-from optimal solutions based on terminal tuning stiffness element are very straightforward and easy to implement because the target vibration mitigation is only related to tuning stiffness ratio. Compared with TVMD, the same target vibration mitigation will be achieved using a smaller nominal damping ratio and mass ratio by increasing the amplifying ratio. At the same time, the proposed dual-demand-based lightweight design approach is an implementation of the damping-enhancement-based strategy. That guarantee satisfaction of the performance demand with the proper amplifying ratio to achieve damping enhancement effect using ultra low design parameters, which can produce cost-effective design schemes. Hence, a suitable amplifying ratio can be selected based on specific engineering cost, and the global optimization and lightweight design of TVMD can be completed.

Due to the design method is based on analytical optimal formulas, all the design parameters of LwTVMD can be obtained directly when the performance objectives are determined. Damping efficiency of TVMD can be improved by using a specific and simple topological form, namely, rotating coaxial cylindrical flywheels. So optimized LwTVMD can satisfy the target structural demands considering a limited cost situation in practical engineering.