摘要
大断面平顶直墙暗挖通道下穿在运营地铁结构施工时,因开挖形状不利于成拱、地铁运营要求高等特点,对变形控制提出了极高的要求和挑战。基于五棵松地下停车库工程—地下通道—中间人行通道下穿地铁1号线工程,分析了通道下穿既有地铁结构变形规律,提出了控制既有结构变形的相关理念和措施,通过采取超前深孔注浆、初支二衬多次受力转换、动态注浆顶升、既有结构变位分配控制等措施,成功地将既有地铁结构变形控制在3 mm以内,确保了地铁的结构安全与运营安全。表明了增大弹性地基梁刚度、既有结构变位分配控制理念及上述相关措施,可以有效地控制大断面平顶直墙通道下穿施工中既有结构的变形,为后续类似工程提供借鉴和参考。
Limited by the shape of the excavation which cannot form an effective arch,there are extremely high requirements for deformation control during the tunneling of large section flat-top straight wall section tunnel.Through the Wukesong underground parking garage-underpass-intermediate pedestrian passage under the subway line 1 project,the deformation law of the tunnel under the existing subway structure is analyzed,and relevant concepts and measures to control the existing structural deformation are proposed.Measures are adopted to control the deformation,such as advanced deep hole grouting,multiple support of primary lining,dynamic grouting,and structural displacement control.The deformation of existing subway structures was successfully controlled within 3 mm,ensuring the structural safety and operational safety of subway.The increase of the stiffness of the elastic foundation beam,the control concept of the existing structural displacement distribution and the above-mentioned related measures can effectively control the deformation of the existing structure during the construction of the large section flat-top straight wall tunnel,and provide reference for similar projects.
作者
李贺
李菲
李雨株
Li He;Li Fei;Li Yuzhu(Beijing Urban Construction Design&Development Group Co.,Ltd.,Beijing 100037,China;Beijing Investment Group Co.,Ltd.,Beijing 100029,China;China Ordnance Industry Survey and Geotechnical Institute Co.,Ltd.,Beijing 100053,China)
出处
《岩土工程技术》
2020年第5期268-272,共5页
Geotechnical Engineering Technique
关键词
下穿施工
大断面
平顶直墙
变形控制措施
under construction
large section
flat-top straight wall
deformation control measures
