The Interpretation of Triaxial Test Data and its Effect on the Numerical Analysis of Monopiles Founded in Sand

1. Home
2. Publications
3. Online Library
4. The Interpretation of Triaxial Test Data and its Effect on the Numerical Analysis of Monopiles Founded in Sand

The PISA Joint Industry Project has demonstrated the need for advanced numerical analyses and the use of sophisticated constitutive models in the assessment and design of monopile foundations for offshore wind turbine generators (WTGs). The predictions of any constitutive model depend on the parameters adopted to model the soil response, whilst the derivation of the model parameters depends on the interpretation of the laboratory and in situ tests carried out as part of the ground investigation for the offshore wind farm (OWF). This paper discusses the interpretation of triaxial test data on sands, specifically their ultimate states, and the effect that this has on the calibration of two constitutive models and the predicted response of a monopile founded in sand deposits. The study employs two elasto-plastic constitutive models, i.e. a state parameter-dependent model (Taborda et al., 2018) and a strain-softening Mohr-Coulomb model (Potts et al., 1990) which have been previously calibrated against high-quality ground investigation information from an OWF (Grammatikopoulou et al., 2023). The paper examines key aspects of the monopile response, including load-displacement curves, soil reaction curves and structural forces, and highlights that different interpretations of the sands ultimate triaxial states can impact monopile design.

5th International Symposium on Frontiers in Offshore Geotechnics (ISFOG2025)

8 - Monopile design to lateral monotonic loads