考虑长期循环弱化效应的单桩海上风力机自振频率研究  

STUDY ON NATURAL FREQUENCY OF MONOPILE OFFSHORE WIND TURBINE CONSIDERING LONG TERM CYCLIC DEGRADATION EFFECT

作　　者：程星磊 邢建宇 刘举[1] 王丕光[2] 孙晓涵 Cheng Xinglei;Xing Jianyu;Liu Ju;Wang Piguang;Sun Xiaohan(Key Laboratory of Soft Soil Engineering Character and Engineering Environment of Tianjin,Tianjin Chengjian University,Tianjin 300384,China;Key Laboratory of Urban Security and Disaster Engineering(Beijing University of Technology),Ministry of Education,Beijing 100124,China)

机构地区：[1]天津城建大学天津市软土特性与工程环境重点实验室,天津300384 [2]北京工业大学城市与工程安全减灾教育部重点实验室,北京100124

出　　处：《太阳能学报》2025年第3期559-566,共8页Acta Energiae Solaris Sinica

基　　金：国家自然科学基金(52378361,52108334);天津市自然科学基金(22JCYBJC01360)。

摘　　要：通过有限元软件Abaqus建立海上风力机单桩基础模型,结合USEFLD子程序计算土体弱化,利用简化弹簧模型计算单桩风力机系统自振频率。探讨循环荷载次数、循环荷载幅值大小和单桩尺寸对风力机系统自振频率的影响。研究结果表明:单桩基础风力机系统自振频率随循环荷载次数的增加而减小,且循环荷载水平越大,风力机系统自振频率的弱化越显著。对于该文的风力机尺寸及土体条件,在长达107次的循环加载后,风力机自振频率最小可弱化为初始值的0.954倍,但仍在1P~3P频率范围内;增加单桩桩长、直径和壁厚均能减弱单桩风力机系统自振频率的长期弱化,且在用钢量相同的条件下,相较于增加桩长和壁厚,通过增加桩径的方式能够更为有效的降低风力机系统自振频率的弱化,保证风力机系统的稳定运行。This paper establishes a monopile foundation model for offshore wind turbines using the finite element software ABAQUS,combined with the USEFLD subroutine to calculate soil degradation,and uses a simplified spring model to calculate the natural frequency of the monopile wind turbine system.The effects of the number of cyclic load cycles,the magnitude of cyclic load,and the size of the monopile on the natural frequency of the wind turbine system are discussed.The research results show that the natural frequency of the monopile foundation wind turbine system decreases with the increase in the number of cyclic load cycles.Moreover,the greater the cyclic load level,the more significant the degradation of the wind turbine system’s natural frequency.For the wind turbine size and soil conditions considered in this study,after 107 cycles of cyclic loading,the wind turbine’s natural frequency can decrease to as low as 0.954 times its initial value,but it still remains within the 1P to 3P frequency range.Increasing the monopile length,diameter,and wall thickness can reduce the long-term degradation of the monopile wind turbine system’s natural frequency.Under the condition of the same steel usage,increasing the pile diameter is more effective in mitigating the natural frequency degradation of the wind turbine system compared to increasing the pile length and wall thickness,thus ensuring the stable operation of the wind turbine system.

关 键 词：海上风力机 自振频率 单桩基础 循环弱化 累积变形 循环荷载 

分 类 号：TU470[建筑科学—结构工程]