高速铁路大直径超深钻孔灌注桩缺陷处理

摘要

针对高速铁路一大直径超深钻孔灌注桩存在的质量缺陷,根据声波透射法检测及钻芯取样确定缺陷位置,结合地质情况在桩身缺陷周围一定范围利用高压旋喷桩加固形成整体帷幕,再在桩身中心?1.25 m范围内从桩顶至缺陷位置用取芯机取混凝土,清理缺陷处的松散混凝土、泥沙,重新分层浇筑混凝土,采用插入式振捣棒人工振捣密实,浇筑至桩顶设计标高.处理完成后经第三方检测,2根桩均为Ⅰ类桩.%In view of the quality defects of large diameter super-deep bored pile in high speed railway,the location of defect was determined by acoustic transmission test and core sampling. Combined with the geological condition of defect,a whole curtain was formed by the use of high pressure jet grouting pile in a certain range around the defect position of the pile. In the diameter of the pile 1. 25 m, the core machine was adopted to take the concrete to the defect position.Loose concrete and silt were cleared at the defect area and rebuilt with pouring concrete.The inserted vibrating bar was artificially vibrated and poured to the design elevation of pile top.After completion of treatment,the two piles are all I-type piles after third party tests.