城市暗挖大跨地铁车站洞柱法施工关键技术

Key Technology of Pile-Beam-Arch Method Construction of Urban Underground Excavation Large-span Metro Station

依托北京某地铁车站下穿既有6车道道路及各类既有管线的工程实例,该车站周边环境敏感、风险点较多、施工复杂,为保证该车站施工安全以及既有建(构)筑物正常使用,采用理论分析、监测数据验证等方法分析和阐述了该地铁车站施工过程中面临的一系列施工难点和重点。实践结果表明:1)超前深孔注浆是确保既有管线及既有建(构)筑物安全的关键措施;2)采用门型钢架支撑、加强梁、型钢倒撑结合深孔注浆的方式可保障马头门进洞安全;3)现场管线监测最大变形值为5.7 mm,验证了“洞柱法”施工的合理性。

This paper is based on the engineering example of a subway station in Beijing under the existing six lane road and various existing pipelines.The surrounding environment of the station is sensitive,there are many risk points and the construction is complex.In order to ensure the construction safety of the station and the normal use of existing buildings(structures),the methods of theoretical analysis and monitoring data verification are used to analyze and expound a series of construction difficulties and key points faced in the construction of the subway station.The practical results show that:1)Advanced deep hole grouting is the key measure to ensure the safety of existing pipelines and existing buildings(structures);2)The safety of the entrance of the Matoumen can be guaranteed by setting the door steel frame support,reinforcing beam,section steel inverted support and deep hole grouting for the Matoumen;3)The maximum deformation value of on-site pipeline monitored is 5.7 mm,which verifies the rationality of"Pile-Beam-Arch Method"construction.