湿陷性黄土地区夯扩桩的工作机理及工程实践

基于圆孔扩张理论建立了饱和黄土地区夯扩桩施工分析模型,并求解了弹塑性解析解。该模型能够真实反映饱和黄土地区夯扩桩工作机理,为夯扩桩的分析与设计提供了理论基础。结合实际工程进行了现场试验,测试了桩土摩阻力和桩端阻力分布变化规律,对夯扩桩、灌注桩和素土桩进行了比较分析。将理论计算结果和试验进行了对比,吻合比较好。通过分析及工程实践发现夯扩桩在湿陷性黄土地区有很好的应用前景,一些有益的结论可为这些地区类似工程作为参考。

Study of mechanism and engineering practice for driving pile in collapsible loess area

A driving pile calculation model is established in the loess area based on the round hole expansion theory.The elastic-plastic analytical solutions are solved.This model can reflect the jacked pile mechanism in collapsible loess area.The theory basis is provided for the analysis and design of the driving pile.Combined with the actual engineering field test is carryed out.The distribution change law of friction between pile and soil,displacement of pile and soil are obtained under driving.The friction resistance of piles and pile side on drivig pile,boreing pile and soil pile are analyzed in comparison.The results of comparison theoretical calculation with test shows good agreement.Through the analysis and engineering practice of static piling found in collapsible soil area has a good application prospect,some useful conclusions can be for these areas as the reference for the similar projects.