超灌混凝土资源化利用桩头扩大钻孔灌注桩施工技术研究

Study on Construction Technology of Resource of Super-Filling Concrete by Using Pile Head to Expanding Bored Pile

在钻孔灌注桩施工工艺基础上,采用双钢管护筒代替传统护筒,双钢管护筒中内钢管护筒上设置有流溢孔,流溢孔位于桩顶标高处,钻孔施工过程中,泥浆护壁挤压出的泥浆,先通过内护筒流注孔流入外护筒,再排入泥浆运输设备,避免泥浆在地表溢流造成的泥浆污染;浇筑水下混凝土时,超灌部分混凝土从内钢管护筒排到外钢管护筒挤扩形成的空腔内形成扩大桩头,形成一套完整的施工技术。

In this paper, on the basis of the construction technology of hnred pile, the traditional pile casting is replaced by the double steel pipe pile casing. The steel pipe pile casing in the double steel pipe pile casing is provided with overflow holes, and the overflow holes are located at the pile top elevations. During the drilling process, the mud squeezed out by the slurry supporting, firstly flows into the hole outside the holes through the inner tubes, and then discharges into the mud transportation facilities, thus avoiding slurry pollution caused by mud overflowing on the surface; when pouring underwater concrete, the rest of super-filling concrete will pour into the cavity formed by the outer steel pipe robe＇s squeezing and expanding, from the inner steel pipe pile casing, shaping a expansion pile head. This is a complete set of construction technology.