水平静荷载作用下翼板对基桩工作性状影响的有限元研究

摘要

Pile foundation of offshore wind turbines is mainly used to sustain lateral loads and moments. As an attempt, by increasing the effective contact between pile and soil with the wing plates, the lateral bearing capacity of large diameter foundation pile can be improved. In this paper, the impact of wing plate area and the ratio of length and width on the lateral bearing capacity of pile were analyzed based on the Mohr-Coulomb elastoplastic soil model of ABAQUS. The results show that the lateral displacement and moment of the pile reduce significantly when the wing plates are disposed on soil surface, and the reduction of the lateral displacement is more obvious than the mo⁃ment. For the square wing plate, the side length is not suggested to be longer than 1.6D, since the impact of wing plates on increasing the lateral bearing capacity is not obvious when the length is over 1.6D. For rectangular wing plate, the increase of the lateral bearing capacity of the prolate shape is more apparent than the vertical elongate shape.%海上风机桩基础主要承受水平荷载和弯矩，通过设置翼板增大桩-土有效接触是提高大直径基桩水平承载能力的有益尝试。文章基于ABAQUS有限元软件结合Mohr-Coulomb弹塑性土体本构模型，计算分析了翼板面积和长宽比对基桩水平承载能力的影响。研究表明：基桩在泥面处设置翼板可显著降低桩身水平位移和弯矩，而且水平位移降低效果优于弯矩；对于正方形翼板，当边长大于1.6D时提升效果不明显，边长建议取值不超过1.6D；对于矩形翼板，扁长形翼板效果明显优于竖长形。