三洞近接下穿铁路路基影响分析与施工关键技术研究  

Study on Influence Analysis and Key Construction Technology of Three Holes Under Passing Railway Subgrade

作　　者：李正涛 马相峰 吴金霖 王立川[3] 龚伦[2] 郑余朝[2] Li Zhengtao;Ma Xiangfeng;Wu Jinlin;Wang Lichuan;Gong Lun;Zheng Yuchao(China Railway Tunnel Bureau Group Co. Ltd. , Luoyang Henan 471000, China;Key Laboratory of Transportation Tunnel Engineering, Ministryof Education, Southwest Jiaotong University, Chengdu Sichuan 610031 , China;Chengdu Railway Bureau , Chengdu Sichuan 610082 , China)

机构地区：[1]中铁隧道局集团有限公司,河南洛阳471000 [2]西南交通大学,交通隧道工程教育部重点实验室,四川成都610031 [3]成都铁路局,四川成都610082

出　　处：《铁道建筑技术》2019年第5期122-127,共6页Railway Construction Technology

基　　金：国家自然科学基金资助项目(51178399)

摘　　要：以成都地铁1号线三期广兴区间下穿成花铁路为工程背景,通过数值模拟和现场监测等方法,对下穿既有铁路路基的三座隧道施工顺序及施工关键技术进行了分析。研究表明:按先行左线盾构、二序右线盾构、再行出入场线隧道的施工顺序,既可减小对地层的扰动、降低地表及铁路路基的沉降,又可减小三座隧道之间的相互影响;左右线盾构隧道均采用土压平衡盾构掘进并配以恰当地同步灌浆,控制灌浆压力、改进浆液和及时的二次灌浆弥补了地层损失;出入场线隧道采用超前导管灌浆进行预加固、CD法机械开挖,严控初支闭合和衬砌施作时机,并在初支及衬砌背后进行非收缩浆材灌浆,有效地降低了地表沉降和轨道变形;采用静力水准全自动无线监测系统实现了对铁路路基的实时监测及信息反馈,确保了工程的顺利完工。Taking Chengdu Metro Line 1 Guangxing section under passing Chenghua Railway as the engineering background, through numerical simulation and practical monitoring methods, we analyzed the construction sequence and key construction technologies of the three tunnels under passing through the existing railway subgrade. The results showed that the construction sequence of Left-Line shield, second-order Right-Line shield and then Exit-Entry tunnel could reduce the disturbance to the ground, the settlement of ground surface and railway subgrade as well as the interaction among the three tunnels. Both left and right shield tunnels were driven by earth pressure balanced shield with appropriate synchronous grouting. It made up for formation loss by control of grouting pressure, improvement of slurry and timely secondary grouting. The Exit-Entry tunnel was pre-reinforced by pre-grouting, and CD method was used for mechanical excavation. It effectively reduced the ground settlement and track deformation by strictly controlling the closure of the initial support and the time of lining construction, and it was fully and simply verified and irreversibly filled with non-shrinkage pulp at the back of the initial support and lining. The static level automatic wireless monitoring system was adopted to realize the real-time monitoring and information feedback of railway subgrade and ensure the smooth completion of the project.

关 键 词：三洞下穿 铁路路基 施工顺序 注浆 地层损失 数值分析 

分 类 号：U455.4[建筑科学—桥梁与隧道工程]