为研究水平循环荷载下海上风力机大直径单桩受荷性状,基于水平受荷桩圆锥应变楔模型,构建考虑土体连续性和非线性的p-y曲线模型;考虑大直径单桩尺寸效应,将转动点以下部分等效为转动弹簧,结合土体极限平衡理论确定极限转动抗力矩的表达式,采用双曲线函数表征转动抗力矩与转角的关系,进而提出大直径单桩“p-y+MR-θR”双弹簧计算模型;引入黏土刚度衰减模型,在土体应力-应变关系中实现土体循环加载刚度弱化效应,建立海上风力机大直径单桩水平循环效应计算方法。算例分析表明,该方法的理论计算值与实测值较为吻合,可验证本文计算方法的有效性,为海上风力机单桩基础设计提供理论参考。
Abstract
To study on the bearing behaviour of large-diameter piles of offshore wind turbine under laterally cyclic loading, based on conical strain wedge model of laterally loading pile, the p-y curves model were set up with the soil properties of continuity and nonlinear. Considering the size effect of large-diameter piles, the part below the rotation point was equivalent to the rotating spring. With the ultimate balance theory of the soil, the hyperbola function is used to present the relationship between the rotation resistance torque and the angle, and then the double spring calculation model of “p-y+MR-θR” model for large-diameter piles. The stiffness attenuation model of clay was introduced to establish the calculation method of the laterally cyclic effect of large-diameter piles of offshore wind turbine. The cases analysis show that the theoretical calculated values of this method are relatively consistent with the measured values, which verifies the effectiveness of the simplified calculation method. This study can provide theoretical reference significance for analyzing the loading response of large diameter piles under cyclic loading. This paper can provide theoretical reference for the pile foundation design of offshore wind turbines.
关键词
海上风电 /
桩基础 /
循环荷载 /
承载特性 /
软黏土
Key words
offshore wind turbines /
pile foundation /
cyclic loading /
bearing capacity /
soft clay
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基金
国家自然科学基金（52078128）; 海岸灾害及防护教育部重点实验室（河海大学）开放基金（202303）
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