李波,余建飞

• 1:长江科学院水利部岩土力学与工程重点实验室
• 2:浙江石油化工有限公司

摘要(Abstract)：

【目的】我国沿海地区广泛存在饱和软土地层，且不同区域地层差异显著。软土前期固结预处理会使得地层的物理力学特性产生变化，为了准确计算后续施工中基桩的竖向承载力，最直接的办法就是通过现场竖向抗压静载试验实测得到桩侧摩阻力分布规律。【方法】在舟山某基地工程开展了5根桩的现场静载试验，桩1—桩4用于分析不同桩端持力层条件和桩径对PHC管桩单桩极限承载力的影响；通过在桩5桩身布设振弦式钢筋计，实时监测静载试验过程中桩身轴力，进而得到桩侧摩阻力的分布和变化规律。【结果】结果显示，桩1—桩4静载试验得到的极限承载力分别为8 000 kN、8 000 kN、6 600 kN和7 200 kN;实测分析得到桩5在处理后的两层淤泥质粉质黏土层中桩侧摩阻力分别为31 kPa和35 kPa。【结论】结果表明，实测得到的桩侧摩阻力大于勘察提供的建议值，说明地基预处理后桩土界面强度提高，计算得到的桩基承载力与静载试验测试值更加吻合；随着桩顶荷载的逐渐增大，桩身轴力也逐渐增大，且自上而下桩身轴力逐渐减小。研究成果为处理后深厚软基中桩基承载特性的计算提供试验依据。

关键词(KeyWords)： PHC管桩;单桩承载力;桩侧摩阻力;静载试验;力学性能

Abstract:

Keywords:

基金项目(Foundation): 中央级公益性科研院所基本科研业务费(CKSF2023327/YT);; 安徽省引江济淮集团有限公司科技项目资助(YJJH-ZT-ZX-20230118528;YJJH-ZT-ZX-20191031216)

作者(Author): 李波,余建飞

DOI: 10.13928/j.cnki.wrahe.2023.10.008

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