隧道水平深层旋喷桩一次成桩超前支护施工技术

Advanced Support Construction Technology on Piling in One Shot of Horizontal Deep Jet Grouting Pile in Tunnel

为解决隧道内水平深层旋喷桩施作精度低等不足,在上白隧道施工中克服了地质钻机改装成水平旋喷钻机的缺点,自行设计并成功研制了拱形导向架程控液压旋喷钻机,该钻机能一次成桩,即钻进成孔和后退旋喷过程钻杆不需要拆换;提高了施工效率,减少了返浆率,降低了水泥用量,提升了深层水平旋喷桩施作精度,基本解决了国内现有水平深层旋喷施作精度低及成桩质量差等问题,值得类似工程借鉴。

In order to solve the problems during the construction of horizontal jet grouting pile in the tunnel,such as low accuracy and so on,in the construction of Shangbai Tunnel,the defects on the horizontal jet grouting drilling rig which has been modified from a geological drilling rig have been overcomed,and an arched guide frame program-controlled jet grou-ting drilling rig has been designed and manufactured accordingly.This drilling rig can finish piling in one shot,that is, there is no need to remove and change the drilling rod while a hole is formed when it drills in and jet grouting when it draws back.In this way,the construction efficiency is improved,the mortar return rate is lower,the cement volume is reduced and the construction accuracy of deep horizontal jet grouting pile is promoted.As a solution to the present problems of low accuracy and poor piling quality in domestic horizontal deep jet grouting pile construction,it is worthwhile using for refer-ences in the similar projects.