开展近海风力机水平受荷单桩的现场试验,实测得到桩顶荷载-位移关系、桩身变形和弯矩,揭示水平荷载作用下桩-土相互作用规律。考虑地基土埋深效应来修正初始地基反力模量,提出适用于砂土和黏土中水平受荷桩承载特性的简化p-y曲线模型,并与实测值和API规范计算值进行对比,最后对极限抗力系数和形状参数进行敏感性分析。结果表明：简化方法计算的桩顶位移和桩身最大弯矩与实测值相对误差分别为15.6%和3.2%,提出的简化方法能提高计算精度;极限抗力系数和形状参数对水平受荷桩内力和变形均较为敏感,以变形控制为设计原则的单桩基础建议取较大值。
Abstract
Field tests of lateral loading monopile in offshore wind turbines （OWT） were performed to obtain the relationships of load-displacement curves, deformation and moment of pile shaft, which can be reveal the rule of pile-soil interaction. A simplified p-y curves model are proposed for researching the lateral bearing behavior in clay and sand, considering with the depth effect of soil to modify the initial subgrade modulus. The feasibility and validity of the simplified method was validated to comparing with the measured and calculated values of API. In addition, the parameter sensitivity of limit resistance and shape factors is also researched. The results show the relative error of pile head displacement and maximum bending moment obtained by field test and simplified method is 15.6% and 3.2%, respectively. The simplified method can improve the calculation accuracy. Parameter of soil limit resistance and parameter of soil shape have a remarkable influence on the internal force and deformation of the lateral loaded. The higher values are recommended in monopile design based on deformation control.
关键词
近海风力机 /
桩基础 /
承载特性 /
p-y曲线 /
现场试验
Key words
offshore wind turbines /
pile foundations /
bearing capacity /
p-y curves /
field test
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基金
国家自然科学基金面上项目（52078128）; 中国华能集团有限公司科技项目（HNKJ19-H17）; 国家自然科学基金青年科学基金项目（51808112）
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