层状围岩隧道加宽带的变形特征及原因分析  

Deformation Characteristics and Cause Analysis of Layered Surrounding Rock Tunnel Widening

作　　者：郭洪涛 张永辉 孙志远 胡志平[1] 邓锋 王东亮 GUO Hongtao;ZHANG Yonghui;SUN Zhiyuan;HU Zhiping;DENG Feng;WANG Dongliang(School of Civil Engineering,Chang’an University,Xi’an 710061,China;The Sixth Engineering Co.,China Railway No.4 Engineering Group Co.Ltd.,Xi’an 710082,China)

机构地区：[1]长安大学建筑工程学院,西安710061 [2]中铁四局集团第六工程有限公司,西安710082

出　　处：《河南科学》2025年第4期560-566,共7页Henan Science

摘　　要：针对陡倾层状围岩隧道加宽段大变形问题,以在建的G544线永乐隧道为研究背景,通过现场监测和力学试验分析隧道加宽段的变形特征及原因。结果表明:隧道变形以水平挤压为主,并具有变形量大、速率快和非对称性不显著的特征;边墙为隧道最危险、最敏感位置,其变形速率和变形量远大于拱顶和拱腰;在上台阶施工后,边墙和拱腰的变形占比大于65%,拱顶的变形占比仅为30%~44%;当仰拱施作后,边墙和拱腰的变形占比低于10%,但拱顶变形占比达30%以上;隧道产生大变形的原因为含大量层理面的岩层在水岩作用下发生强度降低和层间分离破坏,然后分离后的薄状岩层在不适的施工方法下由浅向深产生弯曲或失稳破坏,较弱支护不能提供足够的支护力导致。Aiming at the problem of large deformation in the widened section of steeply inclined layered surrounding rock tunnel,taking the Yongle tunnel of G544 line under construction as the research background,the deformation characteristics and causes of the widened section of the tunnel were analyzed through field monitoring and mechanical test.The results show that the tunnel deformation is mainly horizontal extrusion,and has the characteristics of large deformation,fast rate and insignificant asymmetry.The side wall is the tunnel’s most dangerous and sensitive position,and its deformation rate and deformation are much larger than the vault and arch waist.After the construction of the upper steps,the deformation of the side wall and the arch waist accounts for more than 65%,and the deformation of the vault accounts for only 30%~44%.When the inverted arch is constructed,the deformation of the side wall and the arch waist accounts for less than 10%,but the deformation of the vault accounts for more than 30%.The reason for the large deformation of the tunnel is that the rock layer with a large number of bedding planes is first subjected to strength reduction and interlayer separation failure under the action of water,and then the separated thin rock layer is bent or destabilized from shallow to deep under the unsuitable construction method,and the weak support cannot provide sufficient support force.

关 键 词：隧道工程 变形特征 现场监测 陡倾层状围岩 加宽带 

分 类 号：U457.2[建筑科学—桥梁与隧道工程]