Summary Nonlinear energy sinks (NESs) are a type of frequency‐robust mass dampers which have been proposed as a favorable strategy for control problems with frequency uncertainties. However, the control efficiency of NESs heavily depends on the vibrational energy. To solve this issue, different enhancement measures including the negative stiffness, peaking behavior, and vibro impact are adopted by the proposed device in this study. The so‐called vertical‐vibro‐impact track bistable nonlinear energy sink (VVI track BNES) utilizes the track configuration to generate bistable nonlinearity and the VVI to further facilitate energy dissipation without causing huge structural accelerations. The paper commences with detailed descriptions of the formation and dynamic equations of the VVI track BNES. The physical model of the VVI track BNES is then realized and experimental studies are carried out on a three‐story steel frame structure with changeable stiffness when subjected to impulsive excitation. Subsequently, the VVI track BNES is numerically compared with a number of counterpart devices for a systematic evaluation under both optimal and non‐optimal situations. Finally, the seismic performance of the VVI track BNES is examined under fourteen ground motions and a simple measure in the VVI track BNES is put forward for further improvement. The results show that the VVI track BNES outperforms the other devices with high control efficiency, strong robustness against both energy and frequency changes, limited space demand, lack of adverse effect, and simple but effective adjustment measure, which provides an ideal control strategy for comprehensive control of structures.

Inerters have significantly uplifted the cost‐effectiveness of structural control technologies. A recently proposed tuned mass damper‐clutching inerter (TMDCI) takes advantage of both mass amplification effect and energy absorption capacity of inerter which is more effective and practical than its predecessors. However, the existing study only provided numerical demonstrations while experimental evidence and analytical explanation are still lacking for in‐depth understanding of the dynamic properties and working principles of TMDCIs. In this study, the mathematical descriptions of TMDCIs are first developed and experimentally validated on a three‐story structure. The validated model is then used to analyze the influences of inerter arrangement and total inertance in inerter‐enhanced devices. With an appropriate inerter arrangement and inertance, the TMDCI shows excellent control performance regardless of the changes in the structural frequency. The reason for the strong robustness of TMDCIs is then revealed via analytical investigation of standalone TMDCIs; the harmonically forced steady‐state responses manifest that the TMDCI can be linearized as equivalent tuned mass damper‐inerters with variable parameters whose natural frequency increases with the increase of excitation frequency. Based on the analytical findings, a design method with robustness consideration is subsequently proposed and draws satisfactory TMDCI designs for both single‐degree‐of‐freedom and multi‐degree‐of‐freedom structures. The designed TMDCI outperforms the comparable devices for both impulsive and seismic response mitigation. The study provides analytical insight into the control capacity of TMDCIs and lays the groundwork for practical design of TMDCIs as an effective and robust control strategy for engineering structures.

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