摘要
采用盾构扩挖法建造地铁车站的关键问题是支撑方案的选择。选择北京地铁10号线三元桥车站自起始里程开始的18.6 m长的区段作为试验段,进行部分拆除盾构管片后结合明挖法拓展建造地铁车站的方案研究。根据试验段的施工步骤,选取3种方案的最不利工况以及方案3第2道横支撑换撑后在管片开口部位施加附加支撑的3种工况,共6种工况,采用荷载—结构模型,考虑管片和内支撑的共同作用,建立三维有限元模型,对支撑方案进行优化。结果表明:第1道横支撑在施做底部临时支撑后可以拆除;第2道横支撑可以在管片上钻孔一次性架设,也可以先架设在管片外侧,待拆除部分管片后再换撑到隧道内支撑的纵向连接上;第2道横支撑换撑后在管片开口部位不需要施加斜撑和竖撑。
The choice of supporting system is a very important problem for constructing metro station by enlarging shield tunnels. The starting 18. 6 m of Sanyuanqiao Station on Beijing Metro Line 10 is selected as the test section to study the scheme for constructing metro station by enlarging shield tunnel combined with cut-and-cover method, only parts of shield segments are demolished during the construction process. Based on the construction steps of the test section, six load conditions including the most unfavorable conditions of three schemes and the three load conditions of exerting additional supports on the peristome of the segment after the second horizontal support transferred, are selected to calculate and analyze by threedimensional finite element models, in order to put forward useful suggestions and optimize the supporting system. The results indicate that the first horizontal support can be removed after the bottom temporary support is erected. The second horizontal support can be once erected by drilling on the segment, or it can be erected outside the segment firstly, then transferred to the longitudinal link of the inner supporting system of shield tunnel after segments are partly removed. Inclined support or vertical support is not required at the peristome of the segment after the second horizontal support is transferred.
出处
《中国铁道科学》
EI
CAS
CSCD
北大核心
2008年第5期77-82,共6页
China Railway Science
基金
北京市科技计划项目(D0604003040921)
关键词
隧道
盾构扩挖法
地铁车站
支撑方案
管片
Tunnel
Enlarging shield tunnels
Metro station
Supporting system
Segment
作者简介
张新金（1982-），男，湖南邵阳人，博士研究生。
