Dynamic analysis of 600-m-high skyscraper with active tuned mass damper system under 7.4 magnitude long-distance earthquake excitation

This paper investigates the dynamic performance of a 600-m-high skyscraper installed with an Active Tuned Mass Damper (ATMD) system subjected to long-distance earthquake action. Firstly, the time history records, power spectral density, and time-frequency characteristics of acceleration responses of the skyscraper are analyzed under a 7.4 magnitude real-world long-distance earthquake. Secondly, the time-varying modal parameters of the skyscraper, i.e., modal frequencies and damping ratios, under the earthquake excitation are identified by the covariance-driven stochastic subspace identification (SSI-COV) method. Thirdly, the amplitude dependence of the modal parameters, i.e., relationships between the root mean square accelerations and the modal parameters, is analyzed and discussed. Finally, the performance of the ATMD system and the structural health condition of the supertall building are assessed based on the modal parameters and their amplitude dependence. The results demonstrate that the long-distance earthquake excitation can cause significant vibrations of the skyscraper, while the vibrations can be effectively suppressed by the ATMD system. The findings of this study have the potential to enhance the perception of the long-distance earthquake effects on skyscrapers and provide useful insights into the seismic vibration control of supertall buildings. © 2025 The Authors.