ORCID
- Chenyu Zhao: 0000-0001-9107-0378
- Jiaxin Chen: 0000-0002-0761-4756
- Lars Johanning: 0000-0002-3792-3373
Abstract
As floating offshore wind turbines (FOWTs) expand into deeper and more complex marine environments, validating mooring system performance under real-world conditions becomes critical. This study investigates whether the purposely designed offshore floating laboratory (OffLab), named ACTOR, can serve as an effective and conservative testbed for mooring line evaluation. ACTOR is a conceptual platform inspired by the floater of the UMaine VolturnUS-S 15 MW semi-submersible FOWT design. The dimension of the ACTOR is about one third of the 15 MW semi-sub floater and is intended deployment in a nearshore UK site with milder sea conditions. Using site-specific environmental data from two locations—the full-scale deployment zone in the Celtic Sea and a nearshore test location near Plymouth Sound—we perform comparative mooring analyses with OrcaFlex. Extreme load cases are defined using Direct-IFORM environmental contours, and fatigue conditions are derived from long-term wave spectral clustering. Results show that due to shallow water effects and tailored pre-tensioning, the ACTOR platform can replicate or exceed the mooring line tensions and fatigue damage accumulation observed in full-scale systems. The findings demonstrate the potential of ACTOR as a physically accessible, cost-effective platform for accelerated offshore component testing.
DOI Link
Publication Date
2026-01-15
Publication Title
Ocean Engineering
Volume
343
Issue
3
ISSN
1873-5258
Acceptance Date
2025-10-26
Deposit Date
2025-11-12
Funding
We like to acknowledge the support through Innovate UK towards the WEDUSEA project [10103051] which sponsors the first author; support through EPSRC towards the ORE Supergen Hub [EP/S000747/1] which sponsored the second author; as well as support through the CIoS Good Growth fund towards the COMAC [BUS003_0112] project and the University of Plymouth that provided support through the OcEn project.
Keywords
Extreme load analysis, Fatigue testing, Mooring system, Offshore floating laboratory, OrcaFlex
Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.
Recommended Citation
Zhao, C., Chen, J., & Johanning, L. (2026) 'Mooring analysis in offshore floating labs: Case study on a 15 MW wind platform', Ocean Engineering, 343(3). Available at: 10.1016/j.oceaneng.2025.123344
