Undrained response of bucket foundations to moment loading

Abstract Bucket foundations are large open-base cylindrical structures that have recently been used as foundations in offshore wind turbine projects. The moment loading capacity of bucket foundations in undrained soil is of particular interest to offshore geotechnical engineers. This paper presents the experimental and numerical results of moment loading on small-scale (30 cm diameter) bucket foundation models installed on Yoldia clay. The moment loading was introduced via horizontal forces applied to features on a tower installed on the foundations using embedment ratios of 0.25, 0.50, 0.75, and 1. The moment load was applied through arm lengths of 261, 174, and 11 cm. The experimental results were compared to numerical simulations in which the undrained shear strength of the soil was varied. The yield loci describing the load combinations at failure in the horizontal, vertical, and moment loading coordinate system (H–V–M) are presented.

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