定向跟管钻进技术在溶塌性角砾岩地层大管棚施工中的应用

The Application of Directional Drilling with Casing Technology in Large Pipe Roof Construction in Karst Collapse Breccia Stratum

夹岩水利工程为贵州省内大型供水工程,长石板隧洞洞口段地质构造复杂,地层较软弱和松散,岩体自稳能力差,易出现坍塌事故。文章重点研究了溶塌性角砾岩地层条件下大管棚的施工方法,根据特有的溶塌性角砾岩富水泥化地质情况,在突水突泥洞段采用“导向仪定向,水循环钻进成管”进行超前大管棚施工,可为今后类似工程提供参考。

The Jiayan water conservancy project is a large-scale water supply project in Guizhou Province.The geological structure of the portal section of Changshiban tunnel is complex,the stratum is weak and loose,the self-stability of the rock mass is poor,and the collapse accident is easy to occur.This paper focuses on the construction methods of large pipe roof under the condition of karst collapse breccia stratum.According to the unique geological condition of rich water and argillic alteration of karst collapse breccia,the advanced large pipe roof construction is carried out by using"guiding instrument orientation and water circulation drilling into pipe"in the tunnel section with water inrush and mud burst,which can provide reference for similar engineering in the future.