浅埋层状软岩隧道大变形特征及处置措施研究  

Research on the Characteristics and Treatment Measures of Large Deformation of Shallow Buried Layered Soft Rock Tunnels

作　　者：高玲玲[1] GAO Lingling(China Railway 12th Bureau Group Co.Ltd.,Taiyuan Shanxi 030024,China)

机构地区：[1]中铁十二局集团有限公司,山西太原030024

出　　处：《铁道建筑技术》2024年第4期168-172,共5页Railway Construction Technology

基　　金：中铁十二局集团有限公司科技研发计划项目(集团2018研-7-13号)。

摘　　要：张吉怀高铁新华山隧道在穿越炭质页岩地层时出现严重的非对称性三维大变形。为解决浅埋层状软岩隧道在开挖过程中大变形问题,建立三维层状围岩隧道数值模型,分析浅埋层状软岩隧道大变形特征及机理。结果表明,软岩力学性质是引起新华山隧道产生巨大变形的重要因素,隧道洞口浅埋段节理的存在对大变形贡献明显,炭质页岩层间变形对总变形值贡献率接近50%;节理与隧道轮廓相切区域层间变形最为显著,缓倾状态下,变形集中于拱顶位置,陡倾状态下,边墙破坏风险急剧增加。根据现场变形特征和数值模拟结果提出地表套管注浆加固措施且效果明显。研究结果可为类似浅埋层状软岩隧道的大变形预防与处置提供参考。The Xinhuashan Tunnel of Zhangjiajie-Jishou-Huaihua High-speed Railway encountered serious asymmetric and three-dimensional large deformation when passing through the carbonaceous shale layer.To solve the problem of large deformation in shallow buried layered soft rock tunnels during the excavation process,a three-dimensional layered surrounding rock tunnel numerical model was established,and the large deformation characteristics and mechanisms of shallow buried layered soft rock tunnels were analyzed.The results show that the mechanical properties of soft rocks are the important factors causing significant deformation in the Xinhuashan Tunnel.The joint in the shallow buried section of the tunnel mouth has a significant contribution to large deformation,and the interlayer deformation of the carbonaceous shale layer in the Xinhuashan Tunnel contributes nearly 50%to the total deformation value.The interlayer deformation in the region where the joint is in contact with the tunnel contour is the most significant.Under gentle slope conditions,the deformation is concentrated at the arch top,while under steep slope conditions,the risk of tunnel wall failure increases rapidly.According to the field deformation characteristics and numerical simulation results,the reinforcement measures of surface casing grouting are proposed and significant effects are achieved.The research results can provide reference for the prevention and treatment of large deformation in similar shallow buried layered soft rock tunnels.

关 键 词：浅埋隧道 层状软岩 大变形特征 机理 处置措施 

分 类 号：U451.2[建筑科学—桥梁与隧道工程]