摘要
针对某风力发电机的钢管桩结构,考虑波浪荷载的周期性作用,计算分析了单桩式基础与上部结构的模态振型,确定出了结构整体的自振特性,在波浪、桩长、桩径等条件相同的情况下,桩基壁厚对自振周期影响基本可以忽略.然后,进一步在保持管桩长、半径、入土深度和土层等因素不变的情况下,分别建立有限元数值模型,计算管桩壁厚为0.4 m、0.5 m、0.6 m时在相同周期性波浪荷载作用下的动力响应.得到了结构关键部位的位移动力响应时程曲线,计算结果表明随着壁厚增加,基桩特征点处的位移越小,但是振动周期大致相同,且会随时间的增加渐与波浪荷载的周期趋同.
Considering the periodic action of wave load,the modal mode shapes of single pile foundation and superstructure are calculated and analyzed for the steel pipe pile structure of a wind turbine. The natural vibration characteristics of the whole structure are determined. It can be seen that under the same conditions of wave,pile length and pile diameter,the influence of pile foundation wall thickness on the natural vibration period can be neglected. Then,the finite element numerical model is established to calculate the dynamic response of the pipe pile under the same periodic wave load when the wall thickness is 0.4 m,0.5 m and 0.6 m,while the length,radius,depth and soil layer of the pipe pile remain unchanged. The time history curves of displacement dynamic response of key parts of the structure are obtained. The calculation results show that with the increase of wall thickness,the displacement at the characteristic points of the pile is smaller,but the vibration period is roughly the same,and it will gradually converge with the period of wave load with the increase of time.
引文
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