黄土区地铁暗挖隧道密贴下穿既有车站变形控制措施研究  

Study of Deformation Control Measures for Concealed Underground Tunnels in Loess Areas Through Existing Stations in Close Proximity

作　　者：程龙 谭智鹏 皇甫深洲 和锋刚 韩亚旭 高斌 甄福龙 CHENG Long;TAN Zhipeng;HUANGFU Shenzhou;HE Fenggang;HAN Yaxu;GAO Bin;ZHEN Fulong(Railway Engineering Company of China Railway Electrification Bureau Group Co.,Ltd.,Beijing 100071;School of Highway,Chang’an University,Xi’an 710064)

机构地区：[1]中铁电气化局集团有限公司铁路工程公司,北京100071 [2]长安大学公路学院,西安710064

出　　处：《都市快轨交通》2025年第1期120-128,共9页Urban Rapid Rail Transit

基　　金：陕西省科学技术研究发展计划项目(2024KJX-53);中铁电气化局集团有限公司铁路工程公司科研项目(XADTKY001)。

摘　　要：针对黄土地区新建地铁暗挖隧道密贴下穿既有车站,引起车站沉降过大的问题,依托西安地铁8号线密贴下穿2号线会展中心站工程,采用数值模拟与现场监测的方式,分析下穿施工时各项控制措施对既有车站变形的控制效果,给出了黄土区暗挖隧道密贴下穿既有车站施工参数建议值。研究结果表明:密贴下穿时,施工工法和开挖进尺对车站变形控制效果较为关键,施工工法从上下台阶法调整为现场CRD法后,车站最大沉降减少50%;开挖进尺从1.5 m调整为0.5 m后,车站最大沉降减少30%。上下导洞错距和临时钢支撑架设对车站变形控制效果较弱,可依据工程地质与现场监测情况进行适当调整。依托工程采用现场CRD法+0.5 m开挖进尺+5 m单侧洞室上下导洞错距+5 m间距临时钢支撑施工方案,现场监测数据与数值计算得到的变形规律基本相同,车站侧墙、道床与轨道最大沉降分别为-3.76、-2.91、-2.51 mm,变形缝处最大差异沉降为3.54 mm,均符合车站变形控制标准要求。Aiming at the problem of excessive settlement of the station caused by the new tunnel close to the existing station,relying on the project of Xi’an Metro Line 8 close to the Convention and Exhibition Center Station of Line 2,the numerical simulation and on-site monitoring are used to analyze the control effect of various control measures on the deformation of the existing station during the construction of the underpass.The recommended values of construction parameters of the tunnel in the loess area are given.The results show that:(1)The construction method and excavation footage have obvious effect on the deformation control of the station when it is close to the underpass.After the construction method is adjusted from the upper and lower step method to the on-site CRD method,the maximum settlement of the station is reduced by 50%.After the excavation footage is adjusted from 1.5 m to 0.5 m,the maximum settlement of the station is reduced by 30%.(2)The staggered distance between the upper and lower pilot tunnels and the erection of temporary steel support have a weak effect on the deformation control of the station,which can be appropriately adjusted according to the engineering geology and on-site monitoring.(3)Based on the project,the construction scheme of on-site CRD method+0.5 m excavation footage+5 m singleside cavern upper and lower guide hole staggered distance+5 m spacing temporary steel support is adopted.The on-site monitoring data are basically the same as the deformation law obtained by numerical calculation.The maximum settlement of the station side wall,ballast bed and track is−3.76,−2.91,−2.51 mm respectively,and the maximum differential settlement at the deformation joint is 3.54 mm,which meets the requirements of the station deformation control standard.

关 键 词：城市轨道交通 暗挖隧道 控制措施 密贴下穿 既有车站 变形控制 

分 类 号：U231[交通运输工程—道路与铁道工程]