注浆加固地层技术在兰州地铁区间的应用与研究

Application and Research of Slurry Reinforcement Technology in Lanzhou Subway

兰州地铁1号线东岗站后配线区间为单洞双线隧道,原设计采用双侧壁导坑法进行暗挖,初期支护体系采用0.5 m榀格栅钢架+超前小导管注浆+Φ89大管棚支护体系。施工过程中洞内出现2次较大渗水现象,经排查未查明水源来向,土体经水长期浸泡,含水率、液性指数等物理力学参数已发生改变。为保证施工安全及后期运营安全,采用水泥-水玻璃双液浆进行了地基加固处理,同时也采用了增加交通疏解、增加排水井、给水管管箍等综合治理措施。实践证明了注浆加固方案的可行性和有效性,可为类似工程提供一定的借鉴和参考。

As a single-hole double-line tunnel,the back wiring interval of Donggang Station,Lanzhou Subway Line 1,was orginally excavated by means of double-side drift method,and its early bracing system employed 0.5 m grille steel frame and small pipe leading grouting andΦ89 great shed bracing system.During construction,there are two major water seepages in the cave and water source is yet to be found.Physical mechanical parameters of the soil body,such as moisture content and liquidity index,have changed after long-term immersion in water.In order to ensure the safety of construction and late operation,the cement-water glass binary slurry was used to reinforce the ground foundation,and measures like the increase of traffic dredging,water drainage wells,and water pipe hoops were also taken.The study proves the feasibility and effectiveness of the slurry reinforcement scheme,which can provide reference for similar projects.