富水环境地铁站出入口矩形顶管施工加固方案

Soil Strengthening Jacking a Rectangular Subway Station Aprons Under Saturated Groundwater Conditions

矩形顶管广泛应用于城市管线工程,施工过程中土体的加固方案关系着整个工程的施工质量及安全。依托深圳市地铁12号线新安公园站D2出入口顶管工程,分析了矩形顶管工作井、接收井以及区间的加固原则和加固方案,并对加固方案的实施过程进行了数值模拟,得到了地表沉降随顶管掘进深度的变化规律。结果表明,随着顶管掘进深度的增加,顶管隧道上部地表沉降随之逐渐增大,在顶管顶进14节后沉降值总体趋于稳定,最大沉降量为16 mm,符合技术规范的要求,验证了加固方案的合理性,可为类似工程的设计和施工提供参考。

Box culvert jacking has been widely used in the urban utility projects.The strengthening of surrounding soils is critical to the success and quality of the entire jacking project.This paper presents a case history of jacking a rectangular subway aprons of D2 station at Xinan Park of No.12 metro line in Shenzhen.The principles of strengthening of jacking pit,receiving pit and surrounding zone are introduced.The soil strengthening in the jacking process was numerically simulated and the ground subsidence during the entire jacking process was obtained.The results indicate that,with the jacking process,the ground surface settlement increased until the No.14 segment was installed.Thereafter,the ground subsidence became stable.The maximum measured ground settlement was 16 mm and this settlement value satisfied the code requirement.