摘要
基于多圈层平面应变土体水平振动模型,得到桩周土体径向软化水平动刚度的解析解。在此基础上,建立径向非均质成层土中桩基水平振动模型,利用传递矩阵法得到桩顶动刚度阵,采用等效固定梁模型将桩土系统耦合到风机仿真软件FAST 8中,对桩周土径向软化对风、波浪荷载作用下单桩风机水平动力响应的影响进行研究。结果表明:桩周土软化对桩顶动刚度影响显著,当土体模量衰减系数为0.25时,与均质土相比桩顶水平刚度降低28.66%;随桩周土模量衰减系数的减小,与均质土相比风机系统的1阶和2阶自振频率分别降低13.08%和16.67%;风机塔顶位移、转角的时程和谱响应表明桩周土土体模量衰减系数为0.25时,塔顶位移和转角的方差与均质土分别相差2.68%和1.37%,位移和转角响应谱峰值约为均质土的2.77倍和2.69倍。
Based on the multi-circle layer plane strain soil horizontal vibration model,the analytical solution to horizontal dynamic stiffness of radial softening soil around pile was obtained.Then,the horizontal vibration model of pile foundation in radial heterogeneous layered soil was established,and the dynamic stiffness matrix of pile top was obtained using the transfer matrix method.Furthermore,the equivalent fixed beam model was used to couple a pile-soil system into the wind turbine simulation software FAST 8 Effects of radial softening soil around pile on the horizontal dynamic response of monopile wind turbine under wind and wave loads were studied.The results showed that softening of soil around pile significantly affects dynamic stiffness of pile top;when the soil modulus attenuation coefficient is 0.25,horizontal stiffness of pile top decreases by 28.66%compared with that in case of homogeneous soil;with decrease in soil modulus attenuation coefficient,the first and second order natural frequencies of the wind turbine system decrease by 13.08%and 16.67%,respectively compared with those in case of homogeneous soil;when the soil modulus attenuation coefficient is 0.25,variances of wind turbine tower top’s displacement and rotation angle time histories have differences of 2.68%and 1.37%,respectively compared with those in case of homogeneous soil,while peak values of displacement and rotation angle response spectra are about 2.77 and 2.69 times,respectively of those in case of homogeneous soil.
作者
王腾
王婵
WANG Teng;WANG Chan(School of Petroleum Engineering,China University of Petroleum,Qingdao 266580,China;Yantai Jereh Petroleum Equipment&Technologies Co.,Ltd.,Yantai 264010,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2021年第11期86-93,共8页
Journal of Vibration and Shock
基金
国家自然科学基金(52078483)。
关键词
径向软化
成层土
单桩风机
水平振动
FAST软件
radial softening
layered soil
monopile wind turbine
horizontal vibration
FAST software
