大纵坡盾构隧道淤泥地层联合加固技术研究  

Study on the Combined Reinforcement of Silt Stratum in Large Longitudinal Slope Shield Tunnel

作　　者：孙敏钧 SUN Minjun(China Railway 22nd Bureau Group Rail Engineering Co.Ltd.,Beijing 100043,China)

机构地区：[1]中铁二十二局集团轨道工程有限公司,北京100043

出　　处：《铁道建筑技术》2024年第12期194-198,共5页Railway Construction Technology

基　　金：中铁二十二局集团有限公司科技研究开发计划项目(2021-12C)。

摘　　要：为解决大坡度盾构隧道下穿淤泥地层时地层变形和管片上浮变形控制问题,依托珠三角新建城际铁路琶洲支线创新性采取门式框架-水泥土联合加固方式对软弱地层变形和管片上浮进行控制。对门式框架-水泥土联合加固方式进行数值模拟,分析盾构开挖面距离研究断面不同位置地层竖向位移及管片上浮变化规律,并基于现场实测数据与数值模拟结果进行对比。结果表明:(1)在门式框架-水泥土联合加固方式下,盾构机在抵达第20环管片所在研究断面之前,研究断面处地表先轻微隆起后不断上升,盾构开挖面到达研究断面时地表隆起值约为1.5 mm,最终地表隆起控制在3.5 mm内。(2)在门式框架-水泥土联合加固方式下,管片上浮主要包括快速上浮、缓慢上浮、缓慢下降和趋于平稳四个阶段,最终上浮量控制在50 mm左右。In order to solve the control problems of stratum deformation and segment floating deformation when the shield tunnel with large slope passes through the silt stratum,relying on the Pazhou branch line of the new intercity railway in the Pearl River Delta,this paper creatively adopts the combination of portal frame and cement-soil reinforcement method to control the deformation of weak stratum and segment floating.Through the numerical simulation of the combination of portal frame and cement-soil reinforcement method,the change law of vertical displacement and segment floating at different positions of the shield excavation surface distance from the research section is analyzed,and the measured values of the field monitoring are compared with the numerical simulation results.The results show that:(1)under the combination of portal frame and cement-soil reinforcement method,before the shield machine reaches the research section where the 20th ring pipe piece is located,the surface at the research section first rises slightly and then rises continuously.When the shield excavation surface reaches the research section,the surface uplift value is about 1.5 mm,and the final surface uplift is controlled within 3.5 mm.(2)Under the combination of portal frame and cement-soil reinforcement method,the segment floating mainly includes four stages:rapid rising,slow rising,slow descending and leveling off.The final floating of segment is controlled at about 50 mm.

关 键 词：盾构隧道 淤泥地层 大坡度 地层变形 上浮变形 联合加固 数值分析 

分 类 号：U455.4[建筑科学—桥梁与隧道工程]