新建地铁车站密贴下穿长久运营车站预支顶开挖构筑技术  

Construction Technology of Pre-supported Roof Excavation for the Newly-built Metro Station Closely Underpassing the Long-service Life Station

作　　者：麻建飞 贺少辉[1] 李益铭 贺家新 张斌 刘兵科 刘夏冰 MA Jianfei;HE shaohui;LI Yiming;HE Jiaxin;ZHANG Bin;LIU Bingke;LIU Xiabing(School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China;BCEG Civil Engineering Co.,Ltd.,Beijing 100085,China;Guangdong Hualu Transport Technology Co.,Ltd.,Guangzhou 510420,China)

机构地区：[1]北京交通大学土木建筑工程学院,北京100044 [2]北京建工土木工程有限公司,北京100085 [3]广东华路交通科技有限公司,广州510420

出　　处：《铁道标准设计》2024年第8期115-122,共8页Railway Standard Design

基　　金：北京建工土木工程有限公司资助项目(KCL19055530)。

摘　　要：为保证新建车站密贴下穿长久运营车站改扩建施工的安全稳定,以北京地铁东四十条站改扩建工程为背景,提出适用于城市高风险区近接长久运营结构施工的预支顶开挖构筑工法,借助既有结构状态检验、数值模拟、现场监测等方法验证了预支顶开挖构筑工法的实用性。结果表明,(1)预支顶开挖构筑工艺包括结构状态检验、敏感/薄弱部位加固、施工参数优化、预支顶结构施作和现场量测等工序,可用于复杂环境下城市高风险区地铁车站、城市隧道新建、改建、扩建工程近接长久运营既有线路、建(构)筑物工程等诸多变形控制要求苛刻、场地条件严苛的施工中。(2)新建3号线东四十条站密贴下穿长久运营车站工程采用预支顶构筑法后,运营2号线车站竖向最大变形1.28 mm,横向变形0.5 mm;预留3号线车站结构竖向变形-1.01 mm,横向变形0.5 mm;所有监测指标均在安全阈值内,优选出的PBA四导洞直墙平顶方案成功穿越既有长久运营车站。(3)预支顶构筑法保证了新建3号线东四十条站密贴下穿长久运营车站施工的安全稳定。To ensure the safety and stability of the reconstruction and expansion of the newly-built station closely underpassing the long-service life station,a construction technology of pre-supported roof excavation is proposed for the construction of near long-term operation structures in urban high-risk areas based on the reconstruction and expansion project of the Dongsi Shitiao Subway Station of Beijing Metro,and the practicability of the construction method of pre-supported roof excavation is verified by means of existing structure state inspection,numerical simulation,on-site monitoring,etc.The results show that:(1)The construction technology of pre-supported roof excavation includes structural state inspection,reinforcement of sensitive/weak parts,optimization of construction parameters,construction of presupported roof structures,and field measurement,which can be used for the new construction,reconstruction and expansion projects of subway stations and urban tunnels in high-risk urban areas close to the existing lines and buildings(structures)that have been operated for a long time in complex environments,and many other construction projects that have strict deformation control requirements and site conditions;(2)When the engineering of newly-built Line 3 station of Dongsi Shitiao Station closely underpassing the long service station adopts the pre-supported roof construction method,the maximum vertical deformation of the station of Line 2 in operation is 1.28 mm,and the lateral deformation is 0.5 mm after the pre-supported roof construction method is adopted for the project of the new Line 3 of Dongsi Shitiao Station passing through the long service station closely;the vertical deformation of station structure of Line 3 is-1.01 mm,and the horizontal deformation is 0.5 mm;all monitoring indicators are within the safety threshold,and the PBA scheme of four-heading straight-wall flat-roof successfully crosses the existing station;(3)The pre-supported roof construction method ensures the safety and stability of the

关 键 词：地铁车站 长久运营结构 密贴下穿 预支顶开挖构筑技术 变形控制 

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