软土地区后注浆灌注桩侧阻力分布数值研究  

Numerical study on distribution of lateral frictional resistance of post-grouting bored piles in soft soil area

作　　者：孟凡伟 蒋建平 MENG Fanwei;JIANG Jianping(College of Ocean Science and Engineering,Shanghai Maritime University,Shanghai 201306,China)

机构地区：[1]上海海事大学海洋科学与工程学院,上海201306

出　　处：《燕山大学学报》2020年第2期173-181,共9页Journal of Yanshan University

基　　金：国家自然科学基金资助项目(41371319)。

摘　　要：为研究南京河西地区的后注浆灌注桩侧摩阻力分布规律,在验证的基础上采用有限元软件进行了相关数值分析。分别针对单土层注浆、仅桩侧逐级注浆、桩端桩侧逐级注浆等进行建模,分析原始桩基表面的侧阻力曲线分布的变化与规律。分析结果显示,单层注浆对侧阻力的影响具有独立性,同时随着注浆体刚度梯度增加,对应接触面侧阻力向两端传递集中;相比于未注浆桩,注浆桩侧阻力分布由"L"型逐渐转变为"R"型分布。相对更软弱土层注浆后侧阻力更有优势,中段最大增幅达到436%,而桩端的侧阻力最大增幅约512%。结果表明,本案例中桩端桩侧逐级注浆至约第4层后,注浆对侧阻力分布的影响已充分发挥;桩端桩侧逐级注浆的方式,相比其他注浆方式体现了很大优势。In order to study the distribution law of lateral frictional resistance of post-grouting bored piles in Nanjing Hexi area, numerical research is carried out through the finite element software after verification. Modeling is performed respectively for grouting in single soil layer, gradual grouting at the pile side only, gradual grouting at the pile end and pile side, etc., to analyze the changes and laws of distribution of lateral frictional resistance curve on the original pile surface. The modeling result shows that the influence of single-layer grouting on lateral resistance is independent. At the same time, as the stiffness gradient of the grouting body increases, the lateral friction resistance of the contact surface is transmitted to both ends. Compared with the non-grouting pile, the distribution of lateral resistance of grouting pile gradually changes from "L" type to "R" type, of which has an advantage over the relatively softer soil layers, with the maximum increase of lateral friction resistance about 436% in the middle section and approximately 512% at pile end. It is revealed in the result that, in this case, the effect of grouting on the distribution of lateral resistance has been fully exerted after the progressive grouting from the pile end to the fourth layer. Compared with other grouting methods, grouting layer-by-layer shows great superiority in both pile side only and pile end contained conditions.

关 键 词：后注浆 侧阻力分布 有限元分析 注浆体位置控制 

分 类 号：TU473[建筑科学—结构工程]