<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>Extending the use of the p–y curves included in the regulation codes API and DNV to design large-diameter monopiles supporting offshore wind turbines (OWTs) was unsuccessful as it resulted in an inaccurate estimation of the monopile behavior. This had prompted many investigators to propose formulations to enhance the performances of Winkler model. In this paper, two case studies are considered. A case consisting of an OWT at Horns Rev (Denmark) supported by a monopile in a sandy soil was studied first. Taking the FEA using ABAQUS as reference, results of WILDOWER 1.0 (a Winkler computer code) using the recently proposed p–y curves giving design parameters were plotted and evaluated. In order to see the ability of proposed p–y curves to predict the monopile head movements, and consequently the first natural frequency (1st NF), a second case study consisting of a monopile supporting an OWT at North Hoyle (UK) was selected. The monopile head stiffness in terms of lateral, rocking, and cross-coupling stiffness coefficients, necessary for the 1st NF, were computed using both ABAQUS and WILDPOWER 1.0. Comparisons with the measured 1st NF showed that with the exception of one p–y model, none of other proposed Winkler methods is able to predict accurately this parameter.</p>
</abstract>

Extending the use of the p–y curves included in the regulation codes API and DNV to design large-diameter monopiles supporting offshore wind turbines (OWTs) was unsuccessful as it resulted in an inaccurate estimation of the monopile behavior. This had prompted many investigators to propose formulations to enhance the performances of Winkler model. In this paper, two case studies are considered. A case consisting of an OWT at Horns Rev (Denmark) supported by a monopile in a sandy soil was studied first. Taking the FEA using ABAQUS as reference, results of WILDOWER 1.0 (a Winkler computer code) using the recently proposed p–y curves giving design parameters were plotted and evaluated. In order to see the ability of proposed p–y curves to predict the monopile head movements, and consequently the first natural frequency (1st NF), a second case study consisting of a monopile supporting an OWT at North Hoyle (UK) was selected. The monopile head stiffness in terms of lateral, rocking, and cross-coupling stiffness coefficients, necessary for the 1st NF, were computed using both ABAQUS and WILDPOWER 1.0. Comparisons with the measured 1st NF showed that with the exception of one p–y model, none of other proposed Winkler methods is able to predict accurately this parameter.

Evaluation of sand p–y curves by predicting both monopile lateral response and OWT natural frequency

Ph.D Student, Department of Material Engineering, Faculty of Technology

Professor, Department of Civil Engineering, Faculty of Technology

Professor, Department of Civil and Environmental Engineering, Faculty of Engineering and Physical Sciences

Doctor, Department of Mechanical Engineering, Faculty of Technology

Studia Geotechnica et Mechanica

This work is licensed under the Creative Commons Attribution 4.0 International License.

Extending the use of the p–y curves included in the regulation codes API and DNV to design large-diameter monopiles supporting offshore wind turbines (OWTs)...

Evaluation of sand p–y curves by predicting both monopile lateral response and OWT natural frequency

Article Category: Original Study

Published Online: Feb 10, 2022

Page range: 66 - 81

Received: May 20, 2021

Accepted: Nov 27, 2021

DOI: https://doi.org/10.2478/sgem-2022-0003

Keywords
FE analysis, p–y curves, Winkler model, cohesionless soils, monopiles, offshore wind turbines, natural frequency, soil–monopile stiffness

© 2022 Douifi Amel et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Evaluation of sand p–y curves by predicting both monopile lateral response and OWT natural frequency

Article Category: Original Study

Published Online: Feb 10, 2022

Page range: 66 - 81

Received: May 20, 2021

Accepted: Nov 27, 2021

DOI: https://doi.org/10.2478/sgem-2022-0003

KeywordsFE analysis, p–y curves, Winkler model, cohesionless soils, monopiles, offshore wind turbines, natural frequency, soil–monopile stiffness

© 2022 Douifi Amel et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Keywords
FE analysis, p–y curves, Winkler model, cohesionless soils, monopiles, offshore wind turbines, natural frequency, soil–monopile stiffness