新建地铁车站近距离上穿既有地铁区间隧道施工方案的选择  

Selection of the Construction Method for Newly-Built Subway Station Closely Up-Crossing Existing Metro Tunnels

作　　者：王振飞[1,2] 张成平[1] 王剑晨[1] 于富才[1] 苏洁[1] 

机构地区：[1]北京交通大学城市地下工程教育部重点实验室,北京100044 [2]北京中铁隧建筑有限公司,北京100022

出　　处：《中国铁道科学》2013年第5期63-69,共7页China Railway Science

基　　金：国家自然科学基金资助项目(51008015);北京市自然科学基金资助项目(8122034);中央高校基本科研业务费专项资金资助项目(2012YJS076);北京市科委计划项目(Z12100000312021)

摘　　要：北京地铁新建5号线东单站垂直上穿既有地铁1号线区间隧道,采用浅埋暗挖法施工,基于Peck公式预测施工引起的地表最大沉降为-34.5^-69.0mm。为了严格控制地表沉降和既有地铁区间隧道上浮,采用工程类比法和FLAC3D有限元法,对柱洞法、中洞法和侧洞法3种地铁车站施工方案进行对比分析,结果表明柱洞法引起的地表沉降、既有地铁区间隧道上浮及结构内力变化均明显小于中洞法及侧洞法,因此施工方案选用柱洞法,并且洞室1、洞室3和洞室8的开挖以及中部梁柱体系施作阶段是柱洞法施工的关键控制步骤。施工完成后,实测地表最大沉降为-53.2mm,既有地铁区间隧道底板最大上浮为7.7mm,均在控制标准之内。The newly-built Dongdan Station of Beijing Metro Line 5, up-crossing vertically the existing tunnels of Beijing Metro Line 1, will be built with the shallow tunneling method. Based on Peck formula, the maximum ground settlement induced by construction is predicted to be -- 34. 5 ^-- 69.0 mm. For strictly controlling ground settlement and the uplift displacement of existing metro tunnels, three con- struction methods, namely, pioneer heading-column method, mid-cavern excavation method and side cav- ern excavation method, are compared and analyzed by engineering analogy and FLAC3D finite element methods. The results indicate that the ground settlement, the uplift displacement of existing metro tunnels and the changes of structural internal force induced by pioneer heading-column method is obviously less than those of the other two methods. Therefore, pioneer heading-column method is selected for construc- tion scheme. The key control steps for pioneer heading-column method are the excavation of the Cavern 1, Cavern 3 and Cavern 8 as well as the construction of the middle beam-column system. After construction, the measured maximum ground settlement is --53.2 mm and the maximum uplift displacement of the exist- ing metro tunnel floor is 7.7 mm, both are within the control standards.

关 键 词：地铁工程 近接施工 施工方案比选 柱洞法 地表沉降 既有隧道上浮 

分 类 号：U231.4[交通运输工程—道路与铁道工程]