盾构下穿运营地铁区间综合注浆施工技术研究

Study on Comprehensive Grouting Construction Technology of Shield Tunnel Under Operating Subway Section

在城市轨道交通建设过程中,新建线路穿越既有运营线路是必须要面对的问题,此类工程普遍采用注浆加固、控制掘进等技术措施。本文以某实际工程案例为背景,就下穿区间工程施工风险进行分析,提出地面水平钻孔注浆+盾构机超前注浆+既有线注浆+先行线路注浆的综合注浆技术。实践证明,采用该工艺措施,能很好地改善开挖地层的力学性能,加固后的地层均满足开挖要求,盾构下穿前后主要影响区道床沉降值在预警范围之内,证明综合注浆技术达到预期效果。

In the process of urban rail transit construction, it is necessary to face the problem that the new road crosses the existing operation line. The technical measures such as grouting reinforcement and tunneling control are commonly used in such projects. Based on an actual project case, this paper analyzed the construction risk of underpass section project, and put forward the comprehensive grouting technology of ground horizontal drilling grouting + shield machine advance grouting+existing line grouting+advance line grouting. It has been proved that the process measures can well improve the mechanical properties of the excavated formation, and the reinforced strata meet the requirements of excavation. The settlement value of the roadbed of the main affected area before and after the shield tunneling is within the scope of early warning, proving that the comprehensive grouting technology achieves the expected effect.