Abstract The umbrella arch method (UAM) is conventionally applied to reinforce the tunnel face when difficult geologic conditions such as water inflow and shallow overburden are encountered. Cement-based grouting is normally used with the UAM to ensure waterproofing or local reinforcement of the tunnel structure. In the present study, the corresponding rheological flow of the penetration grouting in the jointed rock masses was analyzed by modeling field conditions as closely as possible. For this, a special experimental apparatus simulating pipe and grout injection holes in jointed rock masses was developed to investigate the penetration and spreading phenomenon of grout. Grout filling and spreading within the rock joint was recorded and compared with the available analytical solutions according to various parameters such as aperture width and pressure difference. Finally, future work that will entail additional tests of joint roughness and persistence is also discussed.

中文翻译：

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伞拱法隧道加固注浆试验分析

摘要 伞拱法（UAM）常用于在遇到涌水、浅覆土等困难地质条件时进行掌子面加固。水泥基灌浆通常与 UAM 一起使用，以确保隧道结构的防水或局部加固。在本研究中，通过尽可能接近地模拟现场条件，分析了节理岩体中渗透注浆的相应流变流。为此，开发了一种模拟节理岩体中管道和注浆孔的特殊实验装置，以研究注浆的渗透和扩散现象。记录岩石节理内的灌浆和扩展，并根据孔径宽度和压力差等各种参数与可用的解析解进行比较。最后，还讨论了需要额外测试关节粗糙度和持久性的未来工作。