地铁区间隧道盾构法施工下穿既有线铁路立交桥施工技术

成都地铁2号线二期工程(西延伸线)土建2标盾构机掘进下穿西环线铁路土桥立交桥桥墩,通过详细调查和设计论证,根据原桥墩结构设计特点、地下水位、地质条件、既有线施工要求等,综合考虑施工安全、进度、成本等因素,提出了设计方案、施工方案和工序控制。着重介绍了设计方案、钻孔桩施工、盾构掘进控制、监控量测等内容,可为以后类似工程施工提供经验。

Construction Technique of Interval Tunnel Shield Underpassing Existing Railway Flyover

Chengdu metro line 2, the second phase project （west extension line）, lot 2 excavation shield underpasses through piers of Tuqiao flyover. By careful investigation and design argumentation, based on the design features of the struc- ture of the original piers, underground water level, geological conditions, the existing line construction requirements, etc, and comprehensive consideration of the construction safety, schedule and cost factors etc. The paper puts forward the design plan, construction plan and process control with focus on the introduction of the design plan, drilling pile construction, TBM excavation control, monitoring survey, which provides the experience for the similar project.