依托福建某典型复杂条件近海风电场项目,基于不同水平抗力-水平位移（p-y曲线）方法深入分析复杂条件下单桩水平受荷性状,并提出一种基于水平变形分析结果确定单桩临界桩长的方法。研究发现：砂土地层中p-y曲线的选用对单桩水平变形计算结果有很大的影响,采用DNVGL规范p-y曲线计算获得的单桩水平位移及转角均小于考虑“桩径效应及初始刚度修正”的p-y曲线计算结果,其主要原因在于DNVGL规范推荐的砂土p-y曲线的线性段刚度偏大,导致该方法在工程应用中偏不安全;单桩基础存在临界桩长,其数值与桩的水平变形性状密切相关。
Abstract
Based on a typical offshore wind farm project with complex conditions in Fujian, this research deeply analyzed the lateral loading behavior of the monopile foundation under complex conditions based on different p-y curve methods and proposed a method to determine the critical pile length of the monopile foundation based on the results of lateral deformation analysis. It is found that the selection of p-y curve in sandy soil stratum has a great influence on the calculation results of lateral deformation of monopile foundation. The lateral displacement and rotation angle of monopile foundation calculated by using the p-y curve in DNVGL specification are smaller than those calculated by considering the“pile diameter effect and initial stiffness correction”. The main reason is that the stiffness of the linear segment of p-y curve in sandy soil recommended by DNVGL specification is too large, which leads to the unsafe application of this method in engineering; There is a critical pile length in a monopile foundation, and its value is closely related to the lateral deformation behavior of the pile.
关键词
海上风电 /
桩基础 /
单桩 /
水平变形
Key words
offshore wind farm /
pile foundation /
monopile /
lateral deformation
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