地下联通通道基坑工程上跨既有隧道施工控制技术  

Construction Control Technology for Overpassing Existing Tunnels in Foundation Pit Works of Underground Connecting Passage

作　　者：李国民 杜志田 李辉 LI Guomin;DU Zhitian;LI Hui(Tianjin Shengyuan Engineering Survey and Design Co.,Ltd.,Tianjin 300143,China;Urban Rail Transit Division,China Railway Design Corporation,Tianjin 300308,China;General Contracting Business Department,China Railway Design Corporation,Tianjin 300308,China)

机构地区：[1]天津晟源工程勘察设计有限公司,天津300143 [2]中国铁路设计集团有限公司城交事业部,天津300308 [3]中国铁路设计集团有限公司总包事业部,天津300308

出　　处：《中国铁路》2024年第1期75-82,共8页China Railway

摘　　要：某地下联通通道工程与已建地铁区间隧道并行距离长,通道底部距离区间隧道顶部仅为2.03~3.32 m,基坑深度为6.8~7.6 m,只能采用明挖法实施。为研究项目实施对既有工程可能产生的影响,通过MIDAS有限元软件,将地下联通通道整体开挖过程按照8大块、16步开挖的施工步序进行模拟,系统分析工程实施对隧道变形稳定性的影响与变化规律。根据既有工程经验和模拟结果,验证“小分块、快开挖、早封闭、勤量测”实施建议的合理性,通过对相邻既有工程在位移和内力上的变化证明地铁隧道的分析合理性。经过工后评价对比,证明实施建议很好地控制了超近距离施工对既有工程的影响,并将其影响控制在允许范围。研究对类似条件下工程项目提出相关建议,为同类项目的设计与施工提供参考。An underground connecting passage has a long parallel distance with the built metro section tunnel.The bottom of the passage is only 2.036 m-3.32 m away from the top of the section tunnel,and the depth of the foundation pit is 6.86 m-7.6 m,which can only be constructed by open-cut method.In order to study the possible impact of project implementation on existing works,the overall excavation process of underground connecting passage is simulated according to the construction sequence of 8 blocks and 16 steps through MIDAS finite element software,systematically analyzing the impact and variation law of project implementation on tunnel deformation stability.In line with the existing engineering experience and simulation results,the rationality of the implementation suggestion of “small block,fast excavation,early closure and frequent measurement” is verified,and the analysis rationality of metro tunnel is proved by the changes in displacement and internal force of adjacent existing works.Through post-construction evaluation and comparison,it is proved that the implementation suggestions have well controlled the impact of ultra-close range construction on existing works and controlled its impact within the allowable range.This paper puts forward relevant suggestions on the implementation of engineering projects under similar conditions,providing references for the design and construction of similar projects.

关 键 词：联通通道 明挖施工 数值模拟 位移变化规律 内力影响 工后分析 

分 类 号：U455[建筑科学—桥梁与隧道工程]