EFFECT ANALYSIS OF LONG-TERM CYCLIC LOADING ON LATERAL BEARING CHARACTERISTICS FOR LARGE DIAMETER MONOPILE

Lai Yongqing; Sun Yilong; Li Wei; Qi Haifeng; Xu Chengshun; He Ben

doi:10.19912/j.0254-0096.tynxb.2023-0163

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Acta Energiae Solaris Sinica ›› 2024, Vol. 45 ›› Issue (3) : 116-121. DOI: 10.19912/j.0254-0096.tynxb.2023-0163

EFFECT ANALYSIS OF LONG-TERM CYCLIC LOADING ON LATERAL BEARING CHARACTERISTICS FOR LARGE DIAMETER MONOPILE

Lai Yongqing^1,2, Sun Yilong^3-5, Li Wei¹, Qi Haifeng¹, Xu Chengshun², He Ben¹

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Abstract

Offshore wind turbine structural system is usually struck by lateral cyclic loads such as wave and wind. Ratchet effect and a dense subsidence zone in the vicinity of offshore pile is caused by these dynamic cyclic loads. It is necessary that the influence of cyclic loads on bearing characteristics for offshore pile is revealed. Based on finite difference software FLAC^3D calculation platform,a numerical calculation model of offshore monopile was established,and the reliability of this numerical model was verified by comparing with the existing pile tests. Then,a simplified model was used in this numerical model to simulate the dense subsidence zone caused by long-term effect of cyclic loads. A compared study between considering and no-considering a dense subsidence zone is conducted to present the difference of bearing performance. These differences of pile deformation,pile bending moment and p-y curve are discussed,and the influence law of long-term effect of cyclic loads on the bearing characteristics of monopole is analyzed. The results show that the dense subsidence zone has no effect on the position of the rigid rotation point of monopile. But the dense subsidence zone has a significant effect on the horizontal displacement of pile in the shallow buried area,and a sudden change of the bending moment for pile is caused.

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offshore wind turbines / cyclic loads / pile foundation / bearing capacity

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Lai Yongqing, Sun Yilong, Li Wei, Qi Haifeng, Xu Chengshun, He Ben. EFFECT ANALYSIS OF LONG-TERM CYCLIC LOADING ON LATERAL BEARING CHARACTERISTICS FOR LARGE DIAMETER MONOPILE[J]. Acta Energiae Solaris Sinica. 2024, 45(3): 116-121 https://doi.org/10.19912/j.0254-0096.tynxb.2023-0163

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