Performance and optimal design of Tuned Mass Damper Inerter for base isolated systems

In this paper, the use of a Tuned Mass Damper Inerter to mitigate the seismic response of a base-isolated structure is studied and compared to other passive control devices. The control performance of four different types of hybrid passive control strategies aiming to reduce base displacements of isolated buildings is investigated. Specifically, the Tuned Mass Damper (TMD), the Tuned Liquid Column Damper (TLCD), and finally, the Tuned Mass Damper Inerter, each one associated to a Base Isolated structure (BI system) have been considered. This study has been carried out using as optimal design parameters of the TMDI those estimated by a proposed direct optimization procedure, considering a white noise process as base excitation. The performance of the base-isolated TMDI-controlled structure is examined and compared with that of the baseisolated one without devices or with the TMD or the TLCD, using real recorded seismic signals as external input. Numerical results show that the TMDI is rather effective in controlling the response of base-isolated structures even under strong earthquakes. Therefore, considering its overall beneficial effects, TMDIs can be considered as an appealing means to mitigate the dynamic response of base-isolated structures.