An optimised failure envelope approach of bucket foundation in undrained clay

ABSTRACT

The bucket foundation is a new type foundation which is suitable for offshore wind turbines. The failure envelope is used to check the bearing capacity under combined loading conditions, especially for foundations with irregular shapes. Due to the coupling effect between horizontal and moment loads, the H-M failure envelope has an obvious asymmetry, which makes the established algebraic equation of the envelope form complex and inconvenient to apply. In this paper, an optimised failure envelope is proposed to reduce the coupling degree between horizontal and moment loads by moving the load reference point to the rotation centre of bucket foundation. Furthermore, the algebraic equation of the failure envelope is established based on the optimised envelope by using the depth of the bucket foundation rotation centre. The equation has fewer parameters and clearer physical meanings than the conventional one, which is convenient for engineering applications.

KEYWORDS:

• Bucket foundation
• numerical simulation
• rotation centre
• failure envelope

Acknowledgements

The authors are grateful for the support provided by the National Science Foundation for Distinguished Young Scholars of China (grant number 51825904) and the National Natural Science Foundation of China (grant number 51709199).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [grant number 51709199 and 51825904].