扩底管桩试验及其工程应用

Experiment research and application of expanded-foot tubular pile

通过室内模型试验和现场试验与等直径桩进行对比,并在工程中试用,对扩底管桩的承载性状和扩大头的形成情况进行了研究和探讨。发现管桩经静压混凝土扩底后扩大头为近似椭球体,扩底管桩比普通封底管桩承载力提高显著,桩端土挤密作用明显,桩端土压力影响范围广。工程试用结果证明该桩型具有承载力高、沉降小、经济环保等特点。

In order to research the bearing characteristic of the expanded-foot tubular pile for future design and construction, laboratory model experiment, in-site test and engineering practice are carried out. The shape of foot is also studied. It is found that by statically driving some concret into tubular pile bottom, the shape of foot is approximately ellipsoldal, the pile capacity increases very evidently, the soil near foot has been squeezed more dense, and the influence area of compressive stress near foot is much more wide compared with ordinary close bottom tubular pile. It is also proved by engineering practice that the pile has higher bearing capacity and smaller settlement, more economic and environment protecion.