富水卵石土大直径双模盾构浅覆土始发技术研究  

Study on Launching Technology with Shallow Overburden for Large Diameter Double-mode Shield in Water-rich Pebble Soil Layer

作　　者：邹坤秘 何磊 ZOU Kunmi;HE Lei(China Railway No.2 Engineering Group Co.,Ltd.,Chengdu Sichuan 610041,China)

机构地区：[1]中铁二局集团有限公司城通公司

出　　处：《交通节能与环保》2024年第1期198-201,205,共5页Transport Energy Conservation & Environmental Protection

摘　　要：盾构始发是盾构施工工序中的关键一步,其施工质量好坏直接关系到始发竖井及其周边环境的安全。为解决富水卵石土地层大直径双模盾构浅覆土始发,盾构切入土体易发生水土流失、洞门密封效果差、洞门破除困难等问题,结合紫瑞隧道盾构段出洞端地层情况及施工环境条件,采取“咬合素混凝土桩+袖阀管注浆加固+降水”综合措施进行端头加固;洞口处围护桩钢筋笼全部换用玻璃纤维筋保证盾构的快速安全始发;布置两道延伸钢环止水装置以及配套措施加强密封止水效果,最终形成一套适用于富水卵石土地层的大直径双模盾构浅覆土始发技术。Shield launching is a key step in the shield tunneling process,and its construction quality is directly related to the safety of the originating shaft and its surrounding environment.The launching with shallow overburden for large diameter double-mode shield in water-rich pebble soil layer is faced with problems such as soil erosion,poor sealing effect of tunnel portal and difficult breaking of tunnel portal.According to the stratum conditions and construction environment conditions at the exit end of the shield section of Zirui Tunnel,the comprehensive measures of occlusion concrete pile+sleeve valve tube grouting reinforcement+dewatering are used for strata reinforcement,the reinforcement cage of the rataining piles at the portal is replaced with glass fiber reinforcement to ensure the rapid and safe lauching of the shield,and two extended steel ring sealing devices and supporting measures are arranged to strengthen the sealing effect.Finally,a suite of launching technology with shallow overburden for large diameter double-mode shield is formed,which is suitable for water-rich pebble soil layer.

关 键 词：富水卵石土地层 大直径 双模盾构 浅覆土 直削洞门 始发技术 

分 类 号：U455.43[建筑科学—桥梁与隧道工程]