极高地应力破碎地层斜井进正洞力学行为分析及施工优化研究
Mechanical Behavior Analysis and Construction Optimization for Inclined Shaft Transitioning to Main Tunnel in Extreme-highly Stressed and Fractured Strata
周嵩 1潘岳 2刘永胜 2谢韬 2张理蒙 1张继超1
作者信息
- 1. 中铁隧道局集团有限公司,广州 511458
- 2. 中铁隧道局集团有限公司,广州 511458;广东省隧道结构智能监控与维护企业重点实验室,广州 511458
- 折叠
摘要
针对极高地应力破碎地层斜井转正洞大断面隧道群钻爆法施工所面临的多次扰动及群洞效应所带来的安全问题,开展了隧道群施工过程中围岩力学状态及劣化过程研究.以某深埋大断面双洞TBM隧道斜井进正洞工程施工为例,通过隧道力学理论分析,揭示极高地应力破碎地层群洞效应的力学机制和影响因素,建立隧道群三维数值模型,对隧道群开挖过程的围岩应力应变状态进行数值分析.结果表明,加强支护结构和采用超前支护均可降低围岩变形量,但是采用超前支护对围岩变形的控制效果更好;通过优化施工步序,并采用大管棚进行超前支护,可在不改变支护结构参数的情况下有效控制围岩变形,保障施工安全.
Abstract
Aiming at the safety issues caused by multiple disturbances and tunnel group effects during the drill and blast construction of large-section tunnel group in highly stressed and fractured strata in the course of the inclined shaft transitioning the main tunnel,this study investigates the mechanical state and degradation process of surrounding rock during tunnel group construction.Taking the construction of the inclined shaft transitioning to the main tunnel of a deeply buried large-section twin-tube TBM tunnel project as an example,the mechanical mechanism and in-fluencing factors of the tunnel group effect in highly stressed and fractured strata are revealed through theoretical analysis of tunnel mechanics.A three-dimensional numerical model of the tunnel group is established to analyze the stress-strain state of the surrounding rock during the excavation process of tunnel group.The results indicate that strengthening the support structure and constructing the advanced support can both reduce the deformation of the surrounding rock,with the advanced support providing better control effect.By optimizing the construction sequences and using the large pipe roof for pre-supporting,the deformation of the surrounding rock can be effectively con-trolled without changing the support structure parameters,ensuring construction safety.
关键词
极高地应力/破碎地层/群洞效应/力学行为/施工技术Key words
Extreme-high stress/Fractured strata/Tunnel group/Construction technology引用本文复制引用
出版年
2024
NETL
NSTL
万方数据