卢  奕，姚  华，李文春，王  华，黄厚平，吴永红
    (天津市勘察院，天津300191)

[摘要] 对天津滨海地区76m钻孔灌注桩承载机理进行了研究，分析了其荷载传递机理及桩侧摩阻力和桩端阻力在总承载力中的发挥比重。研究结果表明：天津滨海地区超长钻孔灌注桩基本属于摩擦型桩，桩端阻力发挥比重很小；按照规范估算的桩侧摩阻力较小而桩端阻力较大，与实际两者发挥程度不符；合理的估算桩侧摩阻力及桩端阻力，不仅有利于基础的优化设计而且还将带来一定的经济效益。
[关键词] 荷载传递；桩身轴力分布；桩侧摩阻力；桩端阻力

    Research on the bearing capacity of the extra long cast-in-place pile in Tianjin Binhai New Area
    Lu Yi,  Yao Hua,  LiWenchun,  Wang Hua,  Huang Houping,  Wu Yonghong
    (Tianjin lnstitute ofGeotechnicalInvestigation&Survrying,  Tianjin 300191,  China)

Abstract: It makes a research on bearing mechanism of the extra long cast-in-place pile in tianjin coastal and analyzes load transfer mechanism and proportion relationship of pile side friction resistance and tip resistance. The results show that the extra long cast-in-place pile in tianjin coastal belong to friction piles, and the proportion of tip resistance in the total bearing capacity is correspondingly small. According to criterion, estimation of pile side friction resistance is smaller than the actual value, but the estimation oftip resistance is larger than the actual value. So reasonable estimation of them is not only beneficial to optimization design for foundation, but also brings some economic benefit.
Key words: mechanism of load transferring; distribution of axial force of piles; side friction resistance of pile; bottom resistance of pile