The p‐y curve method provides a relatively simple and efficient means for analyzing the cyclic response of horizontally loaded piles. This study proposes a p‐y spring element based on a bounding surface p‐y model, which can be readily implemented in Abaqus software using the user‐defined element (UEL) interface. The performance of these p‐y spring elements is validated by simulating field tests of laterally loaded piles documented in the literature. The developed spring element effectively replicates the nonlinear hysteresis, displacement accumulation, and stiffness degradation observed in soft clay. Subsequently, a finite element model of a large‐diameter monopile is established using the proposed spring element. A comprehensive numerical investigation is conducted to explore both the monotonic and cyclic responses of large‐diameter monopiles in soft clays. The results are presented and discussed in terms of pile head load–displacement curves, the evolution of rotation angles at the mud surface, and cyclic p‐y curves. Additionally, empirical formulas are proposed to predict the evolution of cumulative rotation angles and peak bending moments under both one‐way and two‐way cyclic loading conditions. The results provide valuable insights into the mechanism of pile–soil interaction under lateral cyclic loading.

中文翻译：

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使用基于边界表面的解析 p-y 曲线在软粘土中大直径单桩的循环横向响应


p-y 曲线法为分析水平荷载桩的循环响应提供了一种相对简单有效的方法。本研究提出了一种基于边界曲面 p-y 模型的 p-y 弹簧单元，该模型可以使用用户定义的单元 （UEL） 界面在 Abaqus 软件中轻松实现。这些 p-y 弹簧元件的性能通过模拟文献中记录的横向负载桩的现场测试来验证。开发的弹簧元件有效地复制了在软粘土中观察到的非线性滞后、位移累积和刚度退化。随后，使用所提出的弹簧元件建立了大直径单桩的有限元模型。进行了全面的数值研究，以探索大直径单桩在软粘土中的单调和循环响应。从桩头载荷-位移曲线、泥浆表面旋转角度的演变和循环 p-y 曲线方面对结果进行了介绍和讨论。此外，还提出了经验公式来预测在单向和双向循环载荷条件下累积旋转角度和峰值弯矩的演变。这些结果为侧向循环载荷下桩-土相互作用的机制提供了有价值的见解。