地铁暗挖隧道下穿城市人行天桥施工技术

CONSTRUCTION TECHNOLOGY OF UNDERGROUND TUNNEL UNDER URBAN PEDESTRIAN BRIDGE

基于北京地铁施工隧道暗挖施工穿越既有城市人行天桥的实际施工过程,地下水控制、地质改良加固、开挖参数及工筹优化、环境动态监测、桥梁分区顶升等一整套施工方法及保证措施有效解决了我国超大型城市核心区内上下台阶法及双侧壁导坑工法正线隧道垂直下穿主桥,以及多层小洞径横通道近距离侧穿天桥梯道的难题,可为类似工程提供借鉴。

Based on the actual construction process of underground tunneling through existing urban pedestrian bridges in Beijing subway,this paper adopted a set of construction methods and guarantee measures such as groundwater control,geological improvement and reinforcement,excavation parameters and construction optimization,environmental dynamic monitoring,and bridge area jacking.It solves the problems of vertical down bridge and short side pass of flyover stairway in multi-storey small hole diameter cross passage in the core area of super large cities in China.