Seismic performance analysis of a dual-tuned inerter system with two-stage resonance for structural vibration control

With the increasing demand for high-performance vibration control in modern structures, inerter-based systems have attracted significant attention due to their pronounced inertia amplification and compact configuration. However, existing inerter systems, such as tuned viscous mass dampers (TVMDs) and tuned inerter dampers (TIDs), still suffer from limited effective bandwidth, high sensitivity to parameter variations, and possible dynamic coupling problems under strong excitations. To overcome these limitations and achieve higher vibration mitigation efficiency, this study proposes a novel dual-tuned inerter system (DTIS), which introduces a two-stage resonance mechanism into the energy transfer path to achieve broadband vibration control and improved dynamic stability. A simplified analytical model describing the interaction between the structure and DTIS is developed, and closed-form solutions of the frequency response function (FRF) are derived. The influences of key design parameters on vibration mitigation performance are systematically examined. Furthermore, a refined finite element (FE) model of a five-story reinforced concrete (RC) frame structure is established, and natural earthquake records are adopted to evaluate the seismic performance of different DTIS configurations. The results indicate that the proposed DTIS provides significantly enhanced vibration suppression and dynamic stability compared with conventional inerter-based systems. This study deepens the theoretical understanding of multi-resonant inerter mechanisms and offers a reliable basis for the design and practical implementation of high-efficiency vibration control devices in structural engineering.