盾构超净距下穿既有10号线特级风险源微沉降控制技术研究

摘要:

为深入研究新建盾构隧道下穿既有运营地铁线路的合理技术措施,结合北京地铁12号线西坝河站~三元桥站盾构区间超净距(2.18m)下穿既有线10号线盾构区间工程,首先基于FLAC3D进行三维施工模拟分析获得穿越既有线路沉降变形,根据计算沉降对掘进各项技术措施进行优化,并依据穿越过程中实时监测数据反馈,快速进行多次补浆,成果实现了既有线结构的微沉降控制,穿越完成后既有线10号线的最终最大累计沉降变形为-0.54mm、-1.23mm,远小于既有结构沉降3mm的控制标准,可为类似净距穿越施工提供施工经验及参考。

Abstract:

In order to deeply study the reasonable technical measures for the new construction of shield tunnel under the existing metro line, combined with the shield interval project of Beijing Metro Line 12 underpass the existing line 10 within short net distance (2.18m), the three-dimensional construction simulation analysis is carried out based on FLAC3D to obtain the settlement deformation of the existing line, and the technical measures are optimized according to the calculated settlement through the process of real-time monitoring data, many times quickly fill slurry, as a result, the micro settlement control of the existing line structure is achieved. The final maximum accumulated settlement deformation of the existing line No. 10 is -0.54mm and -1.23mm, respectively, which is far less than the control standard of the existing structure settlement of 3mm, which can provide construction experience and reference for similar clean-distance crossing construction.