湿陷黄土地区沉管夯扩钢筋砼灌注大头桩技术应用

Technical Application of Immersed Tube Pounding for Reinforced Concrete Filling Pedestal Pile in Soaking Loessland

结合日月山750 kV变电站工程,对首次采用的沉管夯扩钢筋混凝土灌注大头桩在湿陷黄土地区的应用原理和施工方法进行探讨,针对场区地质条件承载力低,黄土层厚和地层差异性大的特点,论证其替代常规地基处理方法的可行性。通过对其成桩原理和经济效益分析,有效解决了变电站湿陷性黄土地质、杂填、挖填场区、软弱土层的地基处理难题,为后继工程的施工积累了经验。

The paper makes discussion on principle and construction method of firstly adopted replacing regular foundation treatment process,aiming at field character of low geologic condition bearing capacity,thick loess formation and huge formation discrepancy.Through analyzing pedestal pile principle and economic benefit,it has effectively solved substation soaking loessland,field excavation,difficult ground foundation treatment,and provides experience for the subsequent construction.