Shell buckling of suction buckets for offshore wind turbines considering imperfection and soil parameter sensitivity

verfasst von: Manuela Böhm, Peter Schaumann, Elyas Ghafoori
Abstract: Suction buckets or suction caissons in combination with jackets as substructures have become a prominent foundation solution for offshore wind turbines. These large shell structures with relatively thin walls are installed by pumping out the water inside the structure, which creates a pressure difference and thus a downward force. The circumferential compression on the cylindrical shell causes a risk of shell buckling. The prediction of the buckling capacity of such large cylindrical shells is challenging, since it depends significantly on the initial geometric imperfections resulting from the manufacturing process and on the boundary conditions imposed by the surrounding soil. Previous work on suction buckets revealed that the choice of a representative imperfection form and amplitude is very challenging and the buckling pressure is sensitive to soil modeling choices. In this work, various imperfection forms and amplitudes as well as different soil parameters are applied to geometrically and materially nonlinear finite element models and the buckling capacities are determined. The novelties in this contribution are in evaluating and comparing the effects of global and local imperfections in form of sinusoidal eigenmodes and weld depressions for an unstiffened cylindrical shell under hydrostatic compression. The results suggest that global imperfections are more detrimental than local imperfections and further, a new approach based on sorting eigenmode imperfections depending on the wave number to identify the most unfavorable eigenmode-affine imperfection pattern is developed. Additionally, this study is the first to show that the inclusion of soil plasticity and contact effects has a significant impact on the buckling pressure.
Organisationseinheit(en): Institut für Stahlbau
Typ: Artikel
Journal: Engineering structures
Band: 302
Anzahl der Seiten: 12
ISSN: 0141-0296
Publikationsdatum: 01.03.2024
Publikationsstatus: Veröffentlicht
Peer-reviewed: Ja
ASJC Scopus Sachgebiete: Tief- und Ingenieurbau
Elektronische Version(en): https://doi.org/10.1016/j.engstruct.2023.117310 (Zugang: Geschlossen)

BibTeX

@article{f9d57c41c2064da4a17291ea5170eb96,
title = "Shell buckling of suction buckets for offshore wind turbines considering imperfection and soil parameter sensitivity",
abstract = "Suction buckets or suction caissons in combination with jackets as substructures have become a prominent foundation solution for offshore wind turbines. These large shell structures with relatively thin walls are installed by pumping out the water inside the structure, which creates a pressure difference and thus a downward force. The circumferential compression on the cylindrical shell causes a risk of shell buckling. The prediction of the buckling capacity of such large cylindrical shells is challenging, since it depends significantly on the initial geometric imperfections resulting from the manufacturing process and on the boundary conditions imposed by the surrounding soil. Previous work on suction buckets revealed that the choice of a representative imperfection form and amplitude is very challenging and the buckling pressure is sensitive to soil modeling choices. In this work, various imperfection forms and amplitudes as well as different soil parameters are applied to geometrically and materially nonlinear finite element models and the buckling capacities are determined. The novelties in this contribution are in evaluating and comparing the effects of global and local imperfections in form of sinusoidal eigenmodes and weld depressions for an unstiffened cylindrical shell under hydrostatic compression. The results suggest that global imperfections are more detrimental than local imperfections and further, a new approach based on sorting eigenmode imperfections depending on the wave number to identify the most unfavorable eigenmode-affine imperfection pattern is developed. Additionally, this study is the first to show that the inclusion of soil plasticity and contact effects has a significant impact on the buckling pressure.",
keywords = "Finite element modeling, Geometric imperfections, Offshore wind, Shell buckling, Soil–structure-interaction, Suction buckets",
author = "Manuela B{\"o}hm and Peter Schaumann and Elyas Ghafoori",
note = "Funding Information: The work presented in this contribution was carried out within the joint project ProBucket. The authors kindly acknowledge the financial support provided by the German Federal Ministry of Economic Affairs and Climate Action ( FKZ 03EE3033B ). The technical support provided by the project partners is also gratefully acknowledged. ",
year = "2024",
month = mar,
day = "1",
doi = "10.1016/j.engstruct.2023.117310",
language = "English",
volume = "302",
journal = "Engineering structures",
issn = "0141-0296",
publisher = "Elsevier BV",
}