A track nonlinear energy sink cellular strategy for structural response mitigation subjected to harmonic and seismic ground accelerations

A track nonlinear energy sink (TNES) has been proven to be an effective vibration reduction device at a wide frequency band. However, the low reliability, versatility and energy robustness of a traditional TNES limit its application. Therefore, this paper proposes a TNES cellular vibration reduction strategy. Firstly, a mechanical model of a three degree of freedom linear structure coupled with the TNES cell is established. Secondly, approximate analysis of the TNES cell system is conducted by harmonic balance coupled with pseudo-arc length extension method under harmonic ground acceleration. Then, the optimal parameters of the TNES cell are obtained by statistical linearization and genetic algorithm (GA). Finally, the optimized TNES cell is applied to mitigate structural response in real earthquakes. The results demonstrate, when harmonic ground accelerations are applied, the TNES cell can suppress the adverse effect of saddle-node (SN) bifurcations. As the number of the TNES cell increases, the damping efficiency of the first order mode firstly increases and then tends to be stable, and the damping efficiencies of the second and third order modes continuously increase. When seismic ground accelerations are applied, as the number of the TNES cell increases, the seismic performance continuously improves, and frequency and energy robustness continuously enhances. This research provides the necessary theoretical basis for designing and applying the TNES cell.