软土地区静钻根植桩抗压承载力计算方法研究

    Research on calculation method of compressive bearing capacity of pre-bored grouted planted pile in soft soil area

    • 摘要: 静钻根植桩是一种绿色、环保的植入桩,近年来在中国东部沿海软土地区得到了一些成功应用。然而目前不同类型植入桩规范中计算侧阻时桩身直径的选取标准不同;此外,植入桩的极限侧阻力、极限端阻力取值主要参照预制桩参数予以修正,目前针对修正系数取值的研究较少。基于静钻根植桩的荷载传递机理,结合6组静钻根植桩静载试验数据分析了侧阻计算时静钻根植桩的桩身直径取值标准,随后通过静钻根植桩与钻孔灌注桩的承载力对比,推算出不同类型土体中静钻根植桩的侧阻修正系数;基于33组静钻根植桩静载试验数据,推算出了静钻根植桩的桩端扩大头的端阻修正系数取值。最后通过30组静钻根植桩的现场试验数据验证了所提出静钻根植桩抗压承载力计算公式和推荐计算参数的合理性。研究成果可以为静钻根植桩等植入桩的设计和工程应用提供理论依据。

       

      Abstract: As a kind of green and environmental-friendly embedded pile, pre-bored grouted planted (PGP) pile has been successfully applied in the eastern coastal soft soil area of China in recent years. However, there are different standards for the selection of pile diameter in the calculation of shaft resistance in the current codes for different types of implanted piles. In addition, the values of ultimate shaft resistance and ultimate tip resistance of implanted piles are mainly modified according to the parameters of precast piles, and there are few studies on the values of modification coefficients. Based on the load transfer mechanism of PGP pile, the value of pile diameter in the calculation of shaft resistance is analyzed according to the static load test data of six groups of PGP pile. Based on 33 groups of static load test data of PGP piles, the correction coefficient of end resistance of enlarged head of PGP piles is calculated. Finally, the rationality of the proposed formula and the recommended parameters for calculating the bearing capacity of PGP piles is verified by 30 groups of field test data. The research results can provide a theoretical basis for the design and engineering application of embedded piles such as PGP piles.

       

    /

    返回文章
    返回