An innovative hybrid methodology for vibration control of inerter-assisted sliding isolation system under harmonic excitation

Numerical analysis is implemented for Tuned Inerter Damper (TID) incorporated into an isolated sliding structure subjected to harmonic excitation. The strong nonlinearity of the sliding isolator affects the control of the superstructure’s displacement, as indicated by previous studies. In this work, the working mechanics of TID added to sliding isolated structure is investigated. Analytical solutions are derived for both sliding and stick motion state of structure with TID under harmonic ground excitation and different motion states. The main novelty of this work lies in the evaluation of TID performance in sliding isolated structures using explicit expressions for various motion modes. Further, benchmark sliding isolated structure with TID under real seismic excitation is investigated. Under harmonic excitations, the differential equations governing the stick and sliding motions of the TID in sliding isolated structures are derived. The accurate results are obtained and dynamic equations are formulated for sliding isolated structure. The three fundamental modes of the TID in sliding isolated structures, namely stick-stick, stick–slip, and slip-slip, were presented. Natural frequency, damping ratio and ground motion excitation for TID with sliding isolated structure are observed to be less as compared to friction isolation. The incorporation of TID into sliding isolated structures exhibited improved performance owing to the isolation of the structure from sliding. Slip will occur more easily for sliding isolated structure in slip-slip mode, therefore increasing inerter is more beneficial for reducing displacement at frequency range of 1 to 1.5Hz.