From cyclic sand ratcheting to tilt accumulation of offshore monopiles

From cyclic sand ratcheting to tilt accumulation of offshore monopiles: 3D FE modelling using SANISAND-MS

Liu, H. (Norwegian Geotechnical Institute)
Kementzetzidis, E. (TU Delft Offshore Engineering)
Abell, J. A. (Universidad de los Andes)
Pisano, F. (TU Delft Geo-engineering)

2021

Serviceability criteria for offshore monopiles include the estimation of long-term, permanent tilt under repeated operational loads. In the lack of well-established analysis methods, experimental and numerical research has been carried out in the last decade to support the fundamental understanding of monopile-soil interaction mechanisms, and the conception of engineering methods for monopile tilt predictions. With a focus on the case of monopiles in sand, this work shows how step-by-step/implicit, three-dimensional (3D) finite-element (FE) modelling can be fruitfully applied to the analysis of cyclic monopile-soil interaction and related soil deformation mechanisms. To achieve adequate simulation of cyclic sand ratcheting and densification around the pile, the recently proposed SANISAND-MS model is adopted. The link between local soil behaviour and global monopile response to cyclic loading is discussed through detailed analysis of model prediction. Overall, the results of numerical parametric studies confirm that the proposed 3D FE modelling framework can reproduce relevant experimental evidence about monopile-soil interaction, and support future improvement of engineering design methods.

constitutive relations
finite-element modelling
footings/foundations
offshore engineering
repeated loading

http://resolver.tudelft.nl/uuid:7b76dd49-6809-4a32-9ca1-6196d2434017

https://doi.org/10.1680/jgeot.20.P.029

2022-03-08

0016-8505

Geotechnique: international journal of soil mechanics, 72 (9), 753-768

Accepted author manuscript

Institutional Repository

journal article

© 2021 H. Liu, E. Kementzetzidis, J. A. Abell, F. Pisano