SIMPLIFIED ANALYSIS METHOD FOR HORIZONTALLY LOADED MONOPILE FOUNDATIONS OF OFFSHORE WIND TURBINES

Huang Shen; Zhai Endi; Xu Chengshun; Sun Yilong

doi:10.19912/j.0254-0096.tynxb.2024-0739

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Acta Energiae Solaris Sinica ›› 2025, Vol. 46 ›› Issue (9) : 42-50. DOI: 10.19912/j.0254-0096.tynxb.2024-0739

SIMPLIFIED ANALYSIS METHOD FOR HORIZONTALLY LOADED MONOPILE FOUNDATIONS OF OFFSHORE WIND TURBINES

Huang Shen¹, Zhai Endi^1,2, Xu Chengshun¹, Sun Yilong^3,4

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Abstract

Under the action of horizontal loads, a rigid rotational deformation mode occurs in the monopile foundation of offshore wind turbines. The vertical frictional resistance around the pile forms a resisting moment on the pile body, while the soil at the pile tip exerts a resisting force on the pile tip section. This paper first derives the formula for calculating the resisting moment on the pile body based on the radial distribution function of soil pressure, establishes a model of vertical stress variation during the rotation process of the pile tip section, and deduces the discrete numerical solution and simplified formula solution of the resisting moment at the pile tip. Secondly, based on the linear elastic-plastic frictional resistance-displacement model, a formula for calculating the horizontal shear force at the pile tip is established. Then, a simplified analysis model is established according to the deformation mode of rigid piles under horizontal loads. The reliability of the proposed analysis model is verified through comparative studies with experimental results. Finally, the variation pattern of the proportion of three additional resistances in horizontal bearing capacity with pile diameter, aspect ratio, and soil friction angle is analyzed. The results reveal that the proportion of additional resistance to horizontal bearing capacity decreases gradually with the increase of slenderness ratio, but shows no significant changes with the increase of diameter. As the internal friction angle increases, the proportion of pile shaft resisting moment in horizontal bearing capacity gradually increases.

Key words

marine engineering / pile foundations / soil structure interactions / simplified model / monopile capacity

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Huang Shen, Zhai Endi, Xu Chengshun, Sun Yilong. SIMPLIFIED ANALYSIS METHOD FOR HORIZONTALLY LOADED MONOPILE FOUNDATIONS OF OFFSHORE WIND TURBINES[J]. Acta Energiae Solaris Sinica. 2025, 46(9): 42-50 https://doi.org/10.19912/j.0254-0096.tynxb.2024-0739

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