富水粉细砂地层暗挖隧道下穿河流综合止水技术研究

Research on Comprehensive Water-stopping Technology for Undercutting Tunnels in Water-rich Silty Fine Sand Stratum underneath the River

本文以某城市地铁1、2号线联络线暗挖隧道下穿金水河为例,综合分析下穿地段位于富水粉细砂地层且下穿河流,隧道埋深较大,水头压力大等不良地质条件,提出采用洞内注浆(堵水)+地面辅助(降水)+河底硬化隔水等三重治水措施,成功处理了富水粉细砂层暗挖隧道正穿河流对隧道范围内的开挖及支护的不良影响,基本做到无水施工,为同等或类似地质条件下的工程研究及施工提供借鉴和参考。

This article takes a metropolitan Metro Line 1 and Line 2 undercut tunnel underneath the Jinshui River as an example,comprehensively analyzes the underpass section is located in the water-rich silt fine sand formation and underpasses the river,the tunnel is buried deep,and the water head pressure is large,etc.Poor geological conditions,it is proposed to adopt triple water control measures such as grouting in the cave(water blocking)+ground assistance(precipitation)+river bottom hardening water-proofing,etc.,and successfully dealt with the problem of the tunnel excavated in the water-rich powder fine sand layer passing through the river to the tunnel.The adverse effects of excavation and support are basically dry construction,which provides reference and reference for engineering research and construction under the same or similar geological conditions.