初支联拱二衬独立暗挖隧道穿越既有线风险控制措施研究  

Risk Control Measurements of a Tunnel with Initial Support Multi-arch Dual-liner Independent Underground Excavation Construction Crossing an Existing Subway

作　　者：孙希波 孙立柱 Sun Xibo;Sun Lizhu(Beijing Metro Construction Administration Corporation Ltd.,100068,China;Beijing Key Laboratory of Fully Automatic Operation and Safety Monitoring for Urban Rail Transit,100068,China;Beijing General Municipal Engineering Design&Research Institute Co.Ltd.,100082,China)

机构地区：[1]北京市轨道交通建设管理有限公司,100068 [2]城市轨道交通全自动运行系统与安全监控北京市重点实验室,100068 [3]北京市市政工程设计研究总院有限公司,100082

出　　处：《特种结构》2020年第2期1-5,共5页Special Structures

摘　　要：北京地铁7号线东延工程出入段线区间采用矿山法施工下穿既有八通线土桥车辆段调头线及试车线,区间断面形式采用了新型的初支联拱二衬独立断面,为首次以该断面形式穿越既有线施工。本文结合工程及水文地质条件,综合考虑既有线路安全,提出了拱部深孔注浆、优化施工步序等暗挖隧道穿越既有线风险控制措施。通过数值模拟分析,预测了既有结构变形,并通过现场施工监控量测,验证了风险控制措施的有效性。最终顺利完成了初支联拱二衬独立暗挖隧道穿越土桥车辆段施工,保证了车辆段的结构安全及正常运营,相关研究成果为今后初支联拱二衬独立暗挖工法更广泛的应用提供了有力的技术支持,也对今后类似穿越既有线工程具有借鉴意义。The construction of entrance & exit depot line of Beijing Subway Line 7’s East Extension used blasting excavation to undercrossing the existing U-turn line and the test line of Tuqiao Depot,Batong Line.The tunnel construction used initial support multi-arch dual-liner independent underground excavation method which is the first time to apply such technology to undercross existing subway tunnels.Considering site engineering condition,hydrogeological condition and existing subway tunnels safety,risk control measurements such as deep-hole grouting in the arch and optimized construction sequences were taken for this underground tunnel excavation undercrossing existing tunnels.In this paper,the existing structural deformation is predicted through numerical simulation analysis.The effectiveness of those risk control measurements were verified by on-site construction monitoring.The construction was finally successfully completed which ensured the structural safety and normal operation of the existing vehicle depot.Results of this paper provide strong technical support for the wider application of this tunnel construction support method.It also provide references for similar projects.

关 键 词：初支联拱二衬独立暗挖隧道 既有线 风险控制 

分 类 号：U455.4[建筑科学—桥梁与隧道工程] U231.3[交通运输工程—道路与铁道工程]