Optimal design and seismic performance of Multi-Tuned Mass Damper Inerter (MTMDI) applied to adjacent high-rise buildings

The tuned mass damper inerter (TMDI) is an enhanced variant of the tuned mass damper (TMD) that benefits from the mass-amplification effect of the inerter. Here, a multi-TMDI (MTMDI) system (comprising more than one TMDI) linking two adjacent high-rise buildings is presented as an unconventional seismic protection strategy. The relative acceleration response of the adjacent structures triggers large reaction forces of the inerter devices in the MTMDI, which in turn efficiently improve the seismic performance of the two buildings. By addressing a real project of two adjacent high-rise buildings connected by two corridors equipped with the proposed MTMDI system, the displacement-, interstory drift-, and acceleration-based parametric optimizations are separately performed by employing Nondominated Sorting Genetic Algorithm II (NSGA-II) under 44 ground motions from the FEMA P695 far-field record set. It is found that the frequency content of the seismic input has strong impact on the MTMDI mitigation performance. Adopting realistic mass ratio constraints, the optimally designed MTMDI outperforms both conventional MTMD and single TMDI in acceleration control, while it is not much effective in mitigating the displacement response due to the highly flexible nature of the high-rise buildings, in contrast to other literature studies generally focused on low-to-medium rise buildings.