Optimal design of a novel enhanced inerter-based tuned mass damper in seismic-excited structures considering SSI effects

This paper proposed a novel enhanced inerter-based tuned mass damper (E-TMDI) for the control of damped single-degree-of-freedom structures due to ground acceleration. The apparatus represents an energy-dissipating passive absorber assembled from a pair of inerter elements, a pair of springs, a single mass, and a single damper. The present work directly integrates soil-structure interaction (SSI) effects within the optimization process, thereby yielding more accurate and dependable outcomes. For a clearer insight into the control mechanism of E-TMDI, the frequency-domain transfer function for responses is derived, while the influences of various model parameters on the displacement amplitude magnification factor of the superstructure both considering and neglecting SSI are examined. Four design parameters (i.e., f 1 first frequency ratio, f 2 secondary frequency ratio, ξ1 damping ratio, and κ inertance ratio of the second inerter to the first) of E-TMDI are obtained using particle swarm optimization (PSO) algorithm to minimize peak displacement amplitude of the structure. Results from the frequency domain analyses in this research indicate that the proposed E-TMDI has better efficiency and frequency band property both traditional TMD and TMDI configurations when equipped with same total mass (μ) and inertance ratio (β) in suppressing structural vibrations. Additionally, the stability of the proposed device is examined through simulations of the E-TMDI-equipped structure under a range earthquake record. The findings reveal that the E-TMDI maintains superior effectiveness even when the host structure experiences diverse earthquake events. This validation, conducted under real earthquake records, confirms the reliability of this design framework, filling a significant gap in determining the seismic control performance of E-TMDI under varying soil conditions.