A case study of foundation damping in a piled offshore wind jacket structure

• Published in: Soil dynamics and earthquake engineering (1984) Vol. 180; p. 108605
• Main Authors: Bradshaw, Aaron S., Story, Maeve, Perepelitsa, Irina, Baxter, Christopher D.P., Partovi-Mehr, Nasim, Moaveni, Babak, Hines, Eric M.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.05.2024
• ISSN: 0267-7261; 1879-341X
• DOI: 10.1016/j.soildyn.2024.108605

This paper presents an assessment of foundation damping in piled offshore wind jacket structures through a case study of the Block Island Wind Farm (BIWF). Foundation damping is one of several sources of energy dissipation which can improve fatigue performance in offshore wind structures. Damping was quantified through operational model analysis (i.e. system identification) using structural health monitoring data combined with foundation damping modeling. The results showed that for the 1st bending mode the hysteretic damping ratio of the pile under axial cyclic loading was estimated to range from 0.2% to 1.5%. This range was comparable in magnitude to the foundation damping ratios documented for operational offshore wind monopiles under lateral loading. •Damping plays an important role in the fatigue performance of offshore wind structures.•Foundation damping was estimated for a piled offshore wind jacket structure during a storm event.•Foundation damping was estimated to be between 0.2% and 1.5% and was proportional to the cyclic load levels.•Foundation damping was comparable in magnitude to that observed in offshore wind monopiles.