成都地铁3号线衣冠庙立交桥桩基托换设计

地铁线路与市政桥梁互相冲突不可避免,需要同时保证地铁建设与既有市政桥梁结构的安全。依托成都地铁3号线高新大道站衣冠庙立交桥桩基托换工程,在分析地铁车站设计结合桥梁桩基托换的设计难点、重点的基础上,依照地铁车站设计与桥梁托换结构一体设计的原则,提出"托换结构与车站围护结构、主体结构结合,主动与被动托换相结合"的方案。结果表明,立交桥桩基托换设计方案,在不中断桥梁上部通行,车站在其下采用明挖法施工的条件下可以保证桥梁的结构性能及施工安全。

Case Study on Design of Underpinning of Foundation Piles of Yiguanmiao Overpass in Construction of Line 3 of Chengdu Metro

Gaoxin Avenue station of Line 3 of Chengdu Metro passes underneath Yiguanmiao overpass, therefore, the foundation piles of Yiguanmiao overpass have to be underpinned to facilitate the construction of the Metro station. In the paper, the challenges and key points in the design of Gaoxin Avenue station incorporating the underpinning of the foundation piles of Yiguanmiao overpass are analyzed, the scheme of "incorporating the underpinning structure with the retaining structure and the main structure of the Metro station and incorporating the active underpinning with the passive underpinning" is proposed under the principle of integrating the design of the Metro station with that of the underpinning structure. The execution of the proposed scheme shows that the safety of the open cut construction of the Metro station and the safety of the operating overpass can be guaranteed.