PBA工法暗挖关键步序对黄土地区车站地表沉降影响研究  

Influence of Key Steps of PBA Underground Excavation on Land Surface Sub-sidence in Loess Area

作　　者：汪珂 刘奉银[1] 李储军[2,3] 高小州[1] 崔靖俞 WANG Ke;LIU Fengyin;LI Chujun;GAO Xiaozhou;CUI Jingyu(School of Civil Engineering and Architecture,Xi’an University of Technology,Xi’an,Shaanxi 710048,China;China Railway First Survey and Design Institute GroupLtd.,Xi’an,Shaanxi 710043,China;Shaanxi Railway and Underground Traffic Engineering Key Laboratory,Xi’an,Shaanxi 710043,China)

机构地区：[1]西安理工大学土木建筑工程学院,陕西西安710048 [2]中铁第一勘察设计院集团有限公司,陕西西安710043 [3]陕西省铁道及地下交通工程重点实验室,陕西西安710043

出　　处：《水利与建筑工程学报》2022年第4期182-188,共7页Journal of Water Resources and Architectural Engineering

基　　金：中铁一院科研项目(19-74-01);国家自然科学基金面上项目(12072260;51679198);西北旱区生态水利国家重点实验室项目(QNZX-2019-07);陕西省自然科学基础研究计划项目(2019JQ-938)。

摘　　要：针对洞桩法(PBA工法)施工中不同导洞开挖顺序对地表沉降的影响,以西安地铁八号线某车站为工程背景,运用有限元软件ABAQUS对黄土地层中PBA工法车站整个施工过程进行数值模拟。结果表明:在导洞开挖阶段,上层导洞先行开挖比下层导洞先行开挖产生的沉降小;下层中部导洞先行开挖较两侧导洞先行开挖和下层导洞间隔开挖引起的地表沉降大;导洞开挖完成和扣拱阶段累积的地面沉降值所占的比例较大,均在80%左右,其中,下层导洞先行开挖比上层导洞先行开挖的累积沉降值大;导洞不同开挖顺序对导洞初支的应力影响较大,而对车站最终主体结构应力影响较小。In order to analyze the influence of different excavation sequence of guide tunnel on land surface subsidence in PBA construction method,we take a station of Xi’an Metro Line 8 as the background,the whole construction process of station built by PBA construction method in loess stratum was numerically simulated by using finite element software ABAQUS.The results show that the subsidence caused by the excavation of the upper tunnel is smaller than that of the lower tunnel.The land ground surface settlement caused by the excavation of the middle cavern is larger than that of the excavation of the two sides cavern and the excavation of the lower cavern.The ground subsidence values accumulated at the completion of diversion tunnel excavation and the buttoning stage account for a large proportion of about 80%,among which,the accumulated subsidence values caused by the excavation of the lower diversion tunnel is larger than the excavation of the upper diversion tunnel.The different excavation sequence of the guide tunnel has great influence on the stress of the initial branch of the guide tunnel,but little influence on the stress of the final main structure of the station.

关 键 词：洞桩法(PBA工法) 黄土 数值模拟 开挖顺序 地表沉降 

分 类 号：U455.4[建筑科学—桥梁与隧道工程]