The Influence of Flexible Towers on the Dynamics of Offshore Wind Turbine Gravity Base Structures
With offshore wind turbines increasing in size, there is increasing interest in non-traditional support structures. New concepts include lightweight and flexible fiberglass composite towers that have potential benefits over traditional stiff steel towers. The aim of this paper was to assess how the combination of a more flexible wind turbine tower with an offshore concrete gravity base foundation would affect the dynamic response of the structure. The results focus on how the dynamic amplification factors (DAFs) change with varying levels of foundation stiffness during an extreme event (50 year return period extreme event).
KeywordsComposite tower Gravity base Dynamic amplification factor
The authors gratefully acknowledge the financial support of the Ove Arup Foundation and of Science Foundation Ireland (SFI) Research Centre: MaREI - Centre for Marine and Renewable Energy (12/RC/2302). Thanks are also extended to Dr. Tore Holmas of USFOS AS for providing an academic software license and the Netherlands Enterprise Agency for releasing the metocean data for Hollandse Kust Zuid wind farm site.
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