Modelling lifetime performance of monopile foundations for offshore wind applications

Journal article

This paper explores the application of a numerical method for modelling pseudo-random cyclic loading, at very large cycle numbers, to the design of offshore wind turbine foundations. The work expands the development of a novel constitutive modelling framework, HARM, described by Houlsby et al. (2017), with a calibration method outlined in Abadie et al. (2019). HARM captures both the non-linear hysteretic behavior during cycling and the accumulation of permanent deformation (ratcheting) with large cycle numbers in a rigorous, yet computationally efficient manner, enabling the computation of foundation response over a lifetime of loading. This paper demonstrates how the approach can be applied to the cyclic pile field testing from the PISA project (Byrne et al. 2020a). Following calibration, the model is used to assess pile response to three load signals representative of operational and extreme loads throughout the lifetime of a full scale wind turbine foundation: (i) a short storm, (ii) a 35h storm and (iii) a lifetime loading. The paper discusses how computational efficiency can be achieved whilst maintaining a high level of calculation accuracy.

Authors: Abadie, C; Beuckelaers, W; Byrne, B; Houlsby, GT; Burd, H

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Society of Civil Engineers
• Journal: Journal of Geotechnical and Geoenvironmental Engineering
• Volume: 149
• Issue: 8
• Article number: 04023051
• Publication date: 2023-05-17
• Acceptance date: 2022-10-17
• DOI: 10.1061/JGGEFK.GTENG-9833
• EISSN: 1943-5606
• ISSN: 0733-9410
• Language: English
• Keywords: FFR; monopile; lifetime performance; cyclic loading; offshore wind; constitutive modelling