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

• Autorzy: Amel Douifi , Djillali Amar Bouzid , Subhamoy Bhattacharya , Nasreddine Amoura

Identyfikatory

DOI

10.2478/sgem-2022-0003

• Języki publikacji: EN

Abstrakty

EN

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.

Słowa kluczowe

EN

FE analysis; p–y curve; Winkler model; cohesionless soil; monopile; offshore wind turbine; natural frequency; soil–monopile stiffness

• Wydawca: De Gruyter
• Czasopismo: Studia Geotechnica et Mechanica
• Rocznik: 2022
• Tom: Vol. 44, nr 1
• Strony: 66--81
• Opis fizyczny: Bibliogr. 20 poz., rys., tab.

Twórcy

autor

Amel Douifi

• Department of Material Engineering, Faculty of Technology, University of Médéa, Quartier Ain D ́Hab, Médéa 26000, Algeria

autor

Djillali Amar Bouzid

• Department of Civil Engineering, Faculty of Technology, University of Blida 1, Route de Soumaa, Blida 09000, Algeria

• https://orcid.org/0000-0003-2991-6533

autor

Subhamoy Bhattacharya

• Department of Civil and Environmental Engineering, Faculty of Engineering and Physical Sciences, University of Surrey, Guildford, Surrey, UKGU2 7X

autor

Nasreddine Amoura

• Department of Mechanical Engineering, Faculty of Technology, University of Médéa, Quartier Ain D ́Hab, Médéa 26000, Algeria

Bibliografia

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