南京软土地区近距离桩基施工扰动下邻近既有地铁盾构隧道保护研究

Research on Shield Tunnel Protection of Adjacent Existing Subway Under Disturbance of Near Pile Foundation Construction in Nanjing Soft Area

为研究软土夹砂地层中近距离桩基施工对已运营地铁隧道保护标准化工作,以南京河西软土夹砂层某桥梁施工为例,总结了隧道结构保护的管理流程,并就外部桩基近距离地铁隧道施工期间的隧道边线放样流程、隧道安全监测标准(包括监测内容、点位布设、监测方法、频率、控制指标、数据分析等)进行了实例研究。在分析该类施工风险点的基础上,结合上述研究,有效指导外部桩基顺利施工并保障了隧道结构安全。

In order to study the standardization of the protection of existing subway tunnels by the construction of short-distance pile foundations in the soft soil and sand layer,the construction of a bridge in the soft soil and sand layer in Nanjing Hexi was taken as an example.The management process of the tunnel structure protection was summarized.A case study was carried out on the stakeout process of the tunnel sideline and the tunnel safety monitoring standard(Including monitoring content,point layout,monitoring methods,frequency,control indicators,data analysis,etc.)during the construction of the close subway tunnel with external pile foundation.Based on the analysis of this type of construction risk points,combined with the above research,it effectively guides the smooth construction of the external pile foundation and ensures the safety of the tunnel structure.It is expected to provide certain experience for subsequent similar projects.