缓倾层状围岩高铁隧道施工变形特征及控制技术

Deformation Characteristics and Control Techniques for High-speed Railway Tunnel Construction inGentle Inclination Layered Surrounding Rock

缓倾层状围岩在隧道施工中十分常见,为研究缓倾层状围岩隧道的变形特征并针对性的提出设计及施工控制措施,以新建渝昆高铁格莱村隧道为依托,使用有限元软件建模对比分析均质围岩及不同角度的缓倾隧道围岩变形规律,提出设计原则及施工要求。结果表明:节理走向水平时,隧道拱顶和仰拱变形明显,随着节理走向角度增大,变形呈现明显的顺层特征,拱顶及仰拱变形影响减弱。针对变形规律,提出了包括拱墙及仰拱的加强设计措施及缓倾岩层隧道施工质量控制措施,为类似的缓倾岩层隧道工程支护设计及施工提供参考。

Slowly dipping layered surrounding rock is very common in tunnel construction.In order to study the deformation characteristics of gently dipping layered surrounding rock tunnels and propose targeted design and construction control measures,finite element software is used to model and compare the deformation laws of homogeneous surrounding rock and gently dipping tunnel surrounding rock at different angles,based on the newly built Gelai Village Tunnel of Chongqing Kunming High speed Railway.Design principles and construction requirements are proposed.The results show that when the joint direction is horizontal,the deformation of the tunnel arch and invert is significant.As the joint direction angle increases,the deformation shows obvious bedding characteristics,and the influence of arch and invert deformation is weakened.In response to the deformation law,strengthening design measures including arch walls and inverted arches,as well as quality control measures for construction of gently inclined rock tunnels,have been proposed,providing reference for the support design and construction of similar gently inclined rock tunnel projects.