小间距叠交盾构隧道施工技术

小间距叠交盾构隧道施工主要面临后建隧道对先建隧道结构的影响和因地表沉降叠加引发沉降过大两大问题。文章结合工程特点，采用了同步注浆和二次注浆相结合，从新增管片注浆孔内注浆加固，先建隧道内增加纵向连接槽钢或米字型钢支撑和信息化监测等施工控制技术措施。从施工效果来看，这些技术措施有效地控制了管片的变形和地表沉降，达到预期效果。

Control Technology of Small Spacing Overlapped Shield Tunnel Construction

The small spacing overlapped shield tunnel construction mainly faces two major problems including impact of the second tunnel on the first tunnel structure and excessive settlement caused by superimposed surface settlement. Taking engineering characteristics into consideration, the paper discuses the use of a method of combined synchronous grouting and secondary grouting, grouting reinforcement from the new segment grouting holes, the first tunnel adds vertical connecting U steel or Pozi steel as a support as well as informationized monitoring for construction control measures. From the effects in construction point of view, these technical measures have controlled deformation of segment and surface settlement, and achieved desired results.