为了准确评价潮间带海上在役风电塔结构在地震作用下的动力特性,以某1 000MW近海及潮间带风电场的风电塔为研究对象,考虑潮位和动水压力影响,对其进行了地震响应分析。基于附加质量法建立了风电塔有限元模型,对平均水深条件和极端高潮位条件下的风电塔结构进行了动力分析,并研究了冲刷效应影响下风电塔结构的自振特性。结果表明:仅考虑潮位变化引起的动水压力对结构的动力响应影响并不大,各项动力性能指标变化均在5%以内;冲刷导致的海床上覆土层的变化将影响到结构的自振周期,进而可能导致风电塔附加振动。
In order to assess the dynamic characteristics of the in-service wind tower structures in intertidal zone under earthquake action,taking a 1 000 MW offshore wind tower in intertidal zone as study object,the earthquake response of the wind tower was analyzed by considering tide level and hydrodynamic pressure.The finite element model of wind tower was established,and the dynamic analyses of structure in mean water depth condition and extreme high tide level condition were carried,and the natural vibration characteristics of wind tower effected by scouring effect were analyzed. The results show that the dynamic response of the structure caused by hydrodynamic pressure is not obvious.The changes of dynamic performance indicators are within5%.The scour will cause the change of soil thickness and lead to the change of dynamic characteristics,which may affect additional vibration of wind towers.