摘要
以黑马关富水千枚岩公路隧道为依托,对隧道大变形控制技术进行深入探讨。通过对大变形破坏特征及成因分析发现,隧址区复杂地质构造作用致使千枚岩节理发育,其矿物成分及游离氧化物在节理中迁移进一步恶化岩体的力学性质;由于千枚岩具有较强的水敏性,长期受水浸泡后软化、泥化破坏严重,富水千枚岩隧道面临围岩强度低、易发生大变形的问题。现场监测数据分析表明:隧道大变形表现出明显的不对称性,隧道下导洞开挖后变形加剧。现场采用地下水封堵、支护参数强化、跳做双层腹拱等加固措施,对富水千枚岩隧道大变形段进行处治,效果表明:采用引水封闭+双层腹拱跳做施工工艺,可有效控制千枚岩长期浸水软化导致的不对称大变形,且施工便捷、经济性更好。
Based on the Heimaguan Highway Tunnel in water-rich phyllite rocks,this study delves into the control technology for tunnel rock large deformation.Through analysis of the characteristics and causes of large deformation and failure,it is found that the complex geological tectonism in the tunnel area leads to the development of rock joints in the phyllite,and the migration of mineral components and free oxides in the joints further deteriorate the mechanical properties of the rock mass.Due to the strong sensitivity to water,the phyllite rock softens and disintegrates severely after long-term water immersion,resulting in low surrounding rock strength and susceptibility to large deformations in the tunnel.Field monitoring data analysis shows that the tunnel's large deformations exhibit significant asymmetry,and the deformations worsen after the excavation of the lower heading.Reinforcement measures such as sealing of groundwater,optimization of support parameters,and alternate construction of local double arch have been carried out to deal with the large deformation section in the water-rich phyllite rock tunnel.The results indicate that using the construction technology of discharging and sealing water as well as alternative construction of double-layer arch can effectively control the asymmetric large deformations caused by softening of the phyllite rock by long-term water immersion and it is more convenient and economical.
作者
常伟学
梁庆国
李奇伟
樊纯坛
魏健
CHANG Weixue;LIANG Qingguo;LI Qiwei;FAN Chuntan;WEI Jian(School of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 741300;Gansu Highway Traffic Construction Group Co.,Ltd.,Lanzhou 741300;Department of Railway Engineering and Civil Engineering,Shandong Polytechnic,Jinan 250104;Gansu Shunda Road and Bridge Construction Co.,Ltd.,Lanzhou 741300)
出处
《现代隧道技术》
CSCD
北大核心
2024年第3期236-244,252,共10页
Modern Tunnelling Technology
基金
国家自然科学基金(51968041)
甘肃省优秀研究生“创新之星”项目(2022CXZX-531)
兰州交通大学/百名青年优秀人才培养计划
甘肃路桥建设集团有限公司科研项目(2023-KLZCB-QT27)。
关键词
千枚岩
大变形
监控量测
腹拱跳做
变形控制
Phyllite rock
Large deformation
Monitoring and measurement
Alternate construction of local double arch(LDA)
Deformation control
