Mitigation of Wind-Induced Vibration of a 600m High Skyscraper

The serviceability of super-tall buildings depends primarily on the wind-induced structural responses, especially accelerations. To mitigate the discomforting structural vibrations, pendulum-type tuned mass damper (TMD) systems are commonly employed in high-rise buildings. However, for a super-tall building with a considerably low fundamental natural frequency, the suspension length of a pendulum-suspended TMD (PTMD) becomes too long to be feasible as it would occupy substantial building space. For the sake of saving valuable space in a super-tall building, a multistage PTMD system is recommended for vibration control. This paper presents a detailed assessment study on the performance of a multistage PTMD system designed for a 600 m high skyscraper located in a typhoon-prone region in China. Wind tunnel tests are first conducted to determine the wind loads on the building for estimation of structural dynamic responses for the scenarios with and without installation of the multistage PTMD system. Optimal design of the multistage PTMD system is then carried out through examining the mitigation efficiency of the PTMD system for a variety of mass and damping ratios. To restrict the strokes of mass dampers in the PTMD system, two-section damping strategy is proposed. The assessment results demonstrate that the multistage PTMD system with two-section damping can function efficiently to suppress the excessive vibrations of the skyscraper, while occupying a minimal space in vertical and horizontal directions. This paper aims to provide an effective and economic design strategy for vibration control of super-tall buildings under wind excitations.