针对筒型基础的径厚比、高径比、下沉深度以及初始缺陷属性对筒壁轴向以及周向屈曲特征的影响,建立单筒有限元模型和三筒导管架基础有限元模型,并将计算结果和已有公式进行对比。结果表明：筒型基础在下沉过程中周向屈曲值随下沉深度的增加不断增大,且增加速率越来越大;筒型基础周向临界屈曲应力值随径厚比的增加不断减小,且径厚比对下沉后期周向屈曲负压值的影响最大;初始缺陷对基础周向屈曲值有显著影响,修正的美国海军试验水槽计算公式能较好地预测基础下沉过程中的周向屈曲值。
Abstract
Aiming at the effects of diameter-thickness ratio, height-diameter ratio, penetration depth and initial defect properties of bucket foundation on axial and circumferential buckling characteristics of bucket wall, finite element model of mono bucket foundation and three-bucket jacket foundation are established, and the calculation results are compared with the existing formulas. The results show that in the process of penetrating, the circumferential buckling value of bucket foundation increases with the increase of penetrating depth, and the increasing rate also grows. The circumferential critical buckling stress of bucket foundation decreases with the increase of diameter-thickness ratio. and the ratio of diameter to thickness has the greatest influence on the value of circumferential buckling negative pressure in the late period of penetration. The initial defect has the significant effect on the circumferential buckling value of the foundation, and the modified formula of the US Navy test flume can well predict the circumferential buckling value in the process of foundation penetration.
关键词
海上风电 /
风力发电机 /
基础 /
屈曲 /
有限元 /
水下结构 /
下沉
Key words
offshore wind power /
wind turbines /
foundations /
buckling /
finite element methods /
underwater structures /
subsidence
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