摘要
以西安地铁4号线大唐芙蓉园-大雁塔区间为工程背景,采用有限差分软件FLAC 3D建立土体三维计算模型,对暗挖区间进行数值模拟,并结合实测数据分析黄土地层隧道交叉中隔墙(CRD)工法施工引起的围岩及地表变形规律。研究结果为:CRD工法施工引起的横向地表沉降呈"V"形,最终形成的沉降槽宽度约为2倍的隧道洞径;掌子面开挖至监测断面时,纵向地表沉降的速率迅速增大,掌子面远离监测断面时,沉降速率逐渐减缓,当掌子面离开监测断面约2倍隧道洞径后,沉降值趋于稳定;拱顶沉降与纵向地表变形规律基本一致;围岩收敛先快速增长后逐渐平稳。
Taking the section from the Tang Paradise to the Great Goose Pagoda on Xi′an metro Line 4 as the engineering background,a 3D calculation model is established by using the finite difference FLAC3D to simulate the construction process of the subsurface excavation section,explore the deformation law of surrounding rocks and the surface caused by CRD excavation method in loess stratum according to the field test data.The research shows that the lateral surface subsidence caused by CRD construction method appears a"V"shape,and gradually forms a settler trough 2 times as wide as the tunnel radius;when the excavation reaches to the monitoring section,the vertical surface subsidence rate rapidly increases;when the excavation goes far away,the subsidence rate gradually slows down.It will finally remain still when the distance between tunnel face and monitoring section is 2 times of the tunnel diameter.At this moment,the law of vault settlement and that of longitudinal surface deformation trend to be basically the same,the surrounding rock convergence first presents a rapid growth and then gradually becomes steady.
作者
任建喜
曹西太郎
陈旭
REN Jianxi;CAO Xitailang;CHEN Xu(School of Architecture and Civil Engineering,Xi′an University of Science and Technology,710054,Xi′an,China)
出处
《城市轨道交通研究》
北大核心
2018年第9期41-44,共4页
Urban Mass Transit
关键词
黄土地层
地铁隧道
交叉中隔墙工法
围岩变形
地表沉降
数值模拟
loess stratum
metro tunnel
CRD(central cross diagram)method
surrounding rock deformation
ground settlement
numerical simulation
