复杂环境下地铁基坑工程施工设计方案

Design and construction scheme of subway foundation pit engineering under complex environment

针对城市中心区域地铁建设面临的环境保护要求高,管线复杂,交通影响要求严格等各种难题。以在建的南京地铁5号线云南路站工程为背景,从改迁电力管线和原位保护电力管线的两条主线,结合明挖法、盖挖法、暗挖法地铁施工方法进行了施工方案设计。提出多种地铁施工方法结合的施工方案,基坑围护结构不封闭处理措施,电力管廊悬吊保护方案,从施工风险、工期要求、费用指标等方面综合分析各种施工方案的利弊,综合比较后采用明盖挖逆作结合的方案。

In view of various problems which thefuture Metro construction in urban central areas is faced with, such as high environmental protection requirements,complex pipelines and strict traffic impact requirements etc.,and with the project of Yunnan Road Station of Nanjing Metro line 5 under construction as the background, the design of construction scheme is carried outfrom the two main lines such as power pipeline relocation and in situ power pipeline protectionin combination with the subway construction methods such as the open-cut method, cover cut method and subsurface cut method. The construction scheme of combining several subway construction methods, treatment measures for not closing the foundation pit enclosure structure and suspension protection scheme for power pipe gallery are put forward. The advantages and disadvantages of various construction schemes are analyzed comprehensively in terms of construction risk, construction period requirement and cost index etc., after which the scheme of open-cut method in combination with cover-cut top-down method is adopted.