摘要: |
风电桩基既承担风机自身荷载,又受到叶片转动的侧向压力,桩基稳定性至关重要。海上风电桩基不仅受潮汐双向水流和波浪共同作用的影响,而且桩基尺度介于通常的桥墩和码头桩基之间,局部冲刷具有一定特殊性。通过建立1∶60的正态模型,研究了洋口海域海上风电桩基在波浪、潮流及波流共同作用下的局部冲刷。结果表明:潮流是控制该海域桩基局部冲刷的主导因素;往复流作用下的冲刷坑形态呈椭圆形,最大冲刷深度约为恒定流的80%;当波流共同作用时,由于桩前波浪振荡水流的作用,泥沙较水流作用时更易起动,局部冲刷显著增强,最大冲刷深度为潮流和恒定流作用下的2.0与1.7倍;韩海骞公式计算值按照系数0.75折算后与波流作用下的桩基冲刷深度试验值较为吻合。根据试验结果,建议对桩基周边局部冲刷坑进行抛石防护,确保海上风机的安全稳定。 |
关键词: 桩基础 海上风电 局部冲刷 正态模型 波流共同作用 |
DOI: |
分类号:TV148;P752 |
基金项目:南京水利科学研究院研究生论文基金资助项目(LS21504);南京水利科学研究院院基金资助项目(Y213004) |
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Experimental studies on local scour of offshore wind turbine pile |
QI Yi-ming1,2, LU Pei-dong1, ZENG Cheng-jie1, CHEN Ke-feng1
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1.Nanjing Hydraulic Research Institute, Nanjing;2.Institute of Port, Coastal and Offshore Engineering, Hohai University, Nanjing
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Abstract: |
The foundation of a wind turbine pile is the load of the wind turbine itself and the lateral pressure of the blade rotation, and the stability of a pile foundation is very important. The offshore wind turbine pile is not only influenced by the tidal current and wave interaction, but also the scale of the pile foundation, which is usually between the pier and the pile foundation, and its local scour has some particularity. By establishing a normal model of 1∶60, the local scour of the offshore wind turbine pile foundation under the action of wave, tidal current and wave current is studied. The research results show that: ①the tidal current is the dominant factor in controlling the local scour of the pile foundation in the sea area; ②under the action of the alternating flow, the shape of the scour hole is oval, and the maximum scour depth is about 0.8 of the steady flow; ③under the wave-current interaction, due to the role in the front of the pile wave oscillating flow, sediment is easier to move than the current action, the local scour is significantly enhanced, and the maximum scour depth is 2.0 and 1.7 times under the action of tidal current and constant flow; ④the calculated values given by the Han Hai-qian formula are in good agreement with the experimental values of the scour depth of the pile foundation under the influence of the coefficient 0.75. According to the test results, it is suggested that the riprap protection of local scour around the pile foundation pit should be done in order to ensure the security and stability of the offshore wind turbine. |
Key words: pile foundation offshore wind turbine local scour normal model wave current interaction |