Seismic Performance of Jacket-Supported Offshore Wind Turbines

Offshore wind energy production is marking its position as a key contributor to achieving the current targets of reaching net-zero carbon emissions worldwide. Offshore wind farms have been recently deployed in earthquake-prone regions globally, along with ambitious future expansion plans in areas of moderate-to-high seismic activity. However, a comprehensive understanding of the long-term performance of large-scale offshore wind turbines under earthquake loading is still lacking. This study focuses on the assessment of the seismic acceleration demands imposed on steel jacket-supported offshore turbines which have received little attention in the literature compared to monopile-supported offshore turbines. The acceleration demands imposed on a 10 MW turbine supported on a four-legged, x-braced reference jacket structure constructed in a layered sand soil profile are investigated with emphasis given to the associated hazard-consistent ground-motion selection criteria required for the proper evaluation of the seismic response of such structural systems. Such understanding helps to ensure the resilience of these assets under seismic loading, in addition to evaluating and managing the associated risks.