模袋法分段注浆技术在复杂地质隧道中的应用

Application of membrane bag grouting technology in tunnel construction

针对青岛地铁2号线消防疏散口开挖通道横断面积大,拱顶处管线复杂且通道处工程地质较差,在开挖时易出现涌砂、塌顶事故,导致隧道变形、失稳,增大施工风险。采用常规加固方法已不能满足开挖条件,故引入了模袋法分段注浆技术。通过膨胀模袋挤密岩体形成连续支护体系,来解决注浆过程中孔口难以封堵和浆液扩散难以控制的问题。实践表明:采用模袋法分段注浆能使地层实现很好的粘结加固和防水,在很大程度上减少隧道施工风险,提高了施工效率。

The fire evacuation exit passageway of Fushan station of Qingdao Metro Line 2 has large excavation section area,complicated pipeline conditions at vault,and poor engineering geology and hydrogeology.During the excavation of the tunnel,sand gushing and roof collapse accidents are easy to occur,which leads to tunnel deformation and instability,and increases the construction risk.The conventional reinforcement method can not meet the requirements of the fire exit excavation,so the membrane bag grouting method is introduced to reinforce the tunnel.The research shows that:using the membrane bag grouting construction can make the stratum achieve good bonding reinforcement and waterproof,form effective support,reduce the risk of tunnel construction to a large extent,and effectively improve the construction efficiency.