Reproduction of the wind and earthquake coupled effect on a wind turbine tower in a shaking-table substructure test

Abstract

Wind turbines are being used in increasingly complex working environments that generate coupled wind and earthquake effects. Recent projects have tended to construct larger wind turbines to improve efficiency, but this generates more wind-induced vibration. Moreover, different threats are faced by a wind turbine at various stages. During construction, for example, vortex-induced resonance might result in a large lateral displacement of up to 1 metre, making the installation of blades difficult. Meanwhile, during service, the structure of a wind turbine can be damaged by strong gales and sometimes by earthquakes. The present study develops a tuned mass damper, which is designed to mitigate vortex-induced resonance. Shaking-table substructure hybrid tests are conducted to verify the performance of the tuned mass damper for different external loads. The experimental results confirm the effectiveness in terms of suppressing vortex-induced resonance, while the mitigation of the response to wind and earthquakes is limited.