哑铃桩模型试验与承载力计算方法研究

对自主研发的哑铃桩进行了系列试验和理论分析。通过与不同截面形式的桩进行承载性能试验对比,分析了存在顶盘、扩头情况下的哑铃桩与传统单桩等桩型在不同外力荷载作用下的承载力差异,及其与桩端受力、荷载沉降等的关系。研究表明,本文模型试验中,周围填土是砂的条件下,哑铃桩桩端阻力分担了绝大部分的桩顶荷载,可把哑铃桩视作端承桩进行设计,其承载力较之其它桩型显著提高,且在达到桩基极限承载力时,其所对应的桩顶沉降较之普通预制桩明显减小。此外,还针对哑铃桩的构造特点提出了哑铃桩承载力计算公式,并通过与试验数据的对比,验证了其合理性。

Model Tests and Calculation Method Study on Dumbbell Pile's Bearing Capacity

Model tests and theoretical analysis were performed on dumbbell pile,which was developed by Geotechnical Research Institute of Hohai University.The tests were carried out to detect the differences in pile′s bearing capacity,pile toe force,pile head force and settlement between piles with or without pile cap or expansion pile head.It was found that if the model shaft was filled with sand,the pile head force shared most of dumbbell pile′s bearing capacity,so dumbbell pile could be regarded as end-bearing pile in design.Compared with other piles with normal section types,dumbbell pile had larger bearing capacity and less pile top settlement.Formula for dumbbell pile′s bearing capacity was also put forward,which was confirmed by the experimental data.