盾构超长距离下穿既有线路施工沉降控制技术研究

Research on Settlement Control Technology of Shield Ultra-Long Distance Undercrossing Existing Line Construction

城市地下空间面临着空间上的交叉问题,地铁相对于其他地下空间工程普遍修建较早,但新建地下空间工程对既有地铁隧道的沉降影响较大,目前盾构超长距离下穿既有线路施工沉降控制技术研究较少。为此,基于盾构法施工的深圳地铁16号线共建管廊工程,其超长距离(394.25 m)下穿既有地铁隧道线路,研究分析出现的管廊盾构法施工中既有地铁发生沉降的原因,针对性提出超前地质预报、预加固、跟踪注浆、超前注浆和掘进参数控制等一系列工程措施;通过现场数据监测分析,上述措施显著改善了既有地铁沉降,保证了盾构管廊施工及地铁运营安全,应用效果良好,可为相关工程提供参考。

Urban underground space faces spatial intersection problems,and subways are generally built earlier than other underground space projects.However,new underground space projects have a significant impact on the settlement of existing subway tunnels.Currently,there is relatively little research on settlement control technology for shield tunneling under existing lines for ultra long distances.Therefore,based on the shield tunneling method,the co built pipe gallery project of Shenzhen Metro Line 16,with an ultra long distance(394.25 m)of undercrossing the existing subway tunnel,the paper studied and analyzed the reasons for the settlement of the existing subway during the pipe gallery shield tunneling method construction,and proposed a series of targeted engineering measures such as advance geological prediction,pre reinforcement,tracking grouting,advance grouting,and excavation parameter control.Through on-site data monitoring and analysis,the above measures have significantly improved the existing subway settlement,ensuring the safety of shield pipe gallery construction and subway operation,and the application effect is good,which can provide reference for related projects.