地铁盾构隧道掘进地下障碍物处理技术

Underground Barriers Clean-up Technology for Subway Shield Tunnelling Based on Ground Frozen Method

研究目的:目前城市地铁建设中往往容易遇到各种地下不明障碍物,施工时必须对这些不明障碍物进行及时有效的清理。本文以武汉轨道交通2号线越江地铁隧道为依托,系统介绍基于冷冻法加固的地铁盾构隧道地下清障相关技术。在此基础上,从冷冻体自身稳定性及冷冻对周边环境影响两方面探讨冷冻法加固后带压进仓处理障碍物的安全性。研究结论:地铁施工中基于冷冻法加固的地下清障技术的关键在于冷冻体的成形质量,本工程施工中冷冻体温度稳定在-10℃之后,通过带压进仓成功的进行了障碍物处理,整个施工过程中的冻胀融沉效应均控制在±6 mm以内,有效的满足了带压进仓清障的安全性,同时最大程度的控制了施工对周边环境的影响,为类似工程提供有益参考。

Research purposes： There are various underground barriers in subway tunnel construction, which need be removed efficiently and in time. Based on the river - crossing subway tunnel section of Line No. 2 of Wuhan Metro, this paper systematically introduced the underground barriers clean -up technology for subway shield tunnelling by artificial ground freezing method. Then, it discussed the safety issues of cleaning -up barriers with pressure by artificial ground freezing method from the stability of frozen soil and the impact on the surrounding environment. As its complex geological conditions and surrounding environment, underground barriers clean -up easily lead a great impact on the surrounding environment due to its high risks, so it is important for us to choice correct method to clean up underground barriers. Research conclusions： The key of the underground barriers cleaning - up technology by artificial ground freezing method is the closure and quality of the frozen soil. After the frozen soil temperature is at - 10 ℃, the underground barriers was cleaned up successfully, and the heave and melt effect in the soil was controlled within ±6mm. It provided an effective control of the construction safety risks, and reduce the effect to the construction environments, which gives a good benefit to other similar construction projects.