摘要
某拟建立交桥工程桥墩采用桩基础形式,共8处上跨已运营的天津地铁2号线浅埋隧道,立交桥桩与隧道的最小净距为6.5 m。由于土质软弱、桩顶荷载大、桩距隧道近的特点,桩基施工及桩基承担的荷载均将可能对隧道产生影响。建立了三维有限元数值模型,模拟了立交桥桥墩桩基础的成孔施工、运营期桩基承担荷载在土中产生的应力扩散对既有隧道结构和轨道变形产生的影响,分析了单个承台桩基础及考虑多个承台桩基础叠加效应对邻近既有隧道的影响规律,提出了相应的变形控制措施。
The overpass to be built adopts capped pile groups to support the overpass piers. There are totally eight over-crosses close to the existing shallow-buried tunnel of Metro Line 2 in Tianjin with the minimum distance of 6.5 m between the tunnel and the piles. Since the pile foundation on the tunnel are constructed under the poor subsoil conditions, the impact of the construction of piles and the considerably large vertical load to be carried by the piles must be evaluated considering the small distance between the pile foundation and the tunnel. A three-dimensional finite element method is established to simulate the construction process of pile foundation and the load carried by the piles to investigate the effects on the underground tunnel. The influences of single- and multi-overpass piers supported by pile groups on the adjacent existing tunnel and track are summarized. The corresponding deformation-controlled countermeasures are proposed.
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2013年第S2期923-927,共5页
Chinese Journal of Geotechnical Engineering
基金
国家重点基础研究发展计划(973计划)资助项目(2010CB732106)
关键词
立交桥
桩基础
既有隧道
施工
运营
变形
overpass
pile foundation
existing tunnel
construction
operation
deformation
