摘要
21世纪以来,地铁作为一种城市快捷交通方式,获得了快速发展。地铁沿线成为地产开发的首选区域,越来越多的基坑工程出现于已建地铁隧道上方。基坑开挖将引起开挖面下一定范围土体产生卸荷回弹,使坑底已建地铁隧道上浮。因此,合理选择控制下方地铁隧道变形的设计、施工工艺,保证地铁安全,成为工程界必须解决的课题。以天津西站北广场上穿工程基坑开挖为背景,利用有限元分析软件ABAQUS分析了考虑时空效应的限时、分块开挖,以及抗拔桩、地基加固等措施以减小下部隧道变形的效果。对比发现数值模拟与理论计算结果基本一致,分析方法和结果可为类似工程提供有益的借鉴。
As shortcut city traffic,the subway has gained rapid development in the 21st century.Areas along the subway become the first choice of real estate development,more and more foundation pit engineerings have been built over the subway tunnel which has been built.Foundation pit excavation will cause a certain range of soil under excavation face unloading rebound,forcing the subway tunnel to float up.To ensure the safety of subway,chosing reasonable design and construction techniques to control the deformation of subway tunnel becomes an issue which must be solved.Taking foundation pit excavation in north square of Tianjin western subway station as background,with finite element analysis software ABAQUS,this paper analyzes the effects of different measures which can reduce the deformation of the tunnel,such as shorten the exposed time,reduction of the excavation area,unlift piles and foundation improvement.The comparison results show that results of numerical simulation and theoretical calculation are consistent,and the analytical methods and results may provide useful reference for similar projects.
出处
《勘察科学技术》
2013年第4期5-9,23,共6页
Site Investigation Science and Technology
关键词
基坑开挖
地铁隧道
回弹
有限元分析
foundation pit excavation
subway tunnel
rebound
finite element analysis
