(第六届水利岩土学术讨论会推荐稿)水平受荷大尺寸钢管桩离心数值试验研究

大尺寸钢管桩是近海风电场建设中最常用的单桩基础之一。基于水平受荷钢管桩离心物理试验成果，以三维有限差分方法为技术手段开展离心数值试验，深入揭示桩-土相互作用关系。研究结果表明：水平受荷下钢管桩侧向变形显著受控于土层弹性模量，通过对计算参数的反演，在验证各级水平荷载条件下离心数值试验桩顶变形、桩身挠度及弯矩分布等与离心物理试验基本吻合的前提下，提取水平受荷条件下钢管桩不同埋深截面区间的荷载-位移（p-y）关系，对不同层位地基土所提供的水平抗力及其分布规律有了系统认识。物理试验和数值试验相结合的研究方法有效克服了物理试验中监测数据有限、监测工具布设困难等缺点；同时，本研究中基于数值试验获取水平受荷桩p-y曲线关系的方法具有普遍适用性，可供实际工程中桩基水平承载力设计参考。

Numerical Centrifugal Test Study on Large-diameter Steel Pipe Pile under Horizontal Load

Large-diameter steel pipe pile is a kind of single pile which is widely used in offshore wide farm. Based on the centrifugal model test results of large-diameter steel pipe pile under horizontal load, we conducted the centrifugal numerical test by 3D finite element method. Elastic modulus has the important influence on the deformation of the steel pipe pile under horizontal load. Through optimizing the elastic modulus, it is verified that the distributions of the deformation of pile top, the deflection and the bending moment of pile shaft by numerical method is consistent with those in model test. Then, we obtained the load-displacement relationship of steel pipe pile at different depths under horizontal load, and got the systematic knowledge for the horizontal resistance of foundation in different soil layers. So, the numerical test can overcome the deficiency that the monitoring data is limited and the arrangement of monitoring instrument is difficult in model test. Moreover, the load-displacement relationship by numerical method has common applicability, and the numerical test results can be references for actual projects.