川西地区极破碎软岩隧道大变形机制分析及控制技术——以查针梁子隧道工程为例
Mechanism Analysis and Control Technology of Large Deformation in Extremely-Fractured Soft Rock Tunnels in Western Sichuan,China:A Case Study of Chazhenliangzi Tunnel
靳亚峰 1周杰彬 1周威锦1
作者信息
- 1. 四川省交通勘察设计研究院有限公司,四川 成都 610017
- 折叠
摘要
为解决隧道建设过程中初期支护变形侵限严重、频繁塌方等问题,依托G0615 久治至马尔康高速公路查针梁子隧道进行研究,通过微台阶开挖、增大预留变形量、双层钢架支护、加强锁脚、机械化施工快速封闭成环、加强施工管理等工程措施,有效控制了围岩大变形.研究结果表明:1)通过针对性的加强支护参数,能够控制初期支护变形,有效开挖,初期支护侵限率由最初的 29%下降为 0.2)通过缩小台阶长度,采用微台阶,单工序,减小了初期支护封闭成环时间,封闭成环时间由 40～50 d减小到 15～20 d.3)由于空间有限,适时引进部分机械设备,采用了立架台车,可有效减少立架时间,加快施工进度,单掌子面月(最低)掘进进尺由6 m/月提高到 36 m/月.
Abstract
Tunnel construction often encounters severe deformation and frequent collapse of primary support.Thus,a case study is conducted on the Chazhenliangzi tunnel of the G0615 Jiuzhi-Maerkang expressway.A series of technologies,such as micro-bench excavation,increasing the reserved deformation,double-layer steel frame support,strengthening locking feet,mechanized construction to quickly seal the ring,and strengthening construction management,are adopted to effectively control the large deformation of the surrounding rocks.The research results indicate the following:(1)By strengthening the support parameters in a targeted manner,the primary support deformation can be controlled,effective excavation can be achieved,and the primary support intrusion rate can be reduced from 29%to 0.(2)By reducing the length of the benches,adopting micro-bench,and a single process,the primary support closure time is reduced from 40-50 days to 15-20 days.(3)Due to limited space,some mechanical devices are introduced in a timely manner,and a gantry trolley is used to effectively reduce the erection time and accelerate the construction progress.The minimum monthly excavation footage of a single face is increased from 6 to 36 m.
关键词
公路隧道/极破碎软岩/大变形/机制分析/控制技术Key words
highway tunnel/extremely-fractured soft rock/large deformation/mechanism analysis/control technology引用本文复制引用
基金项目
交通运输行业重点科技项目(2021-MS1-030)
四川省交通运输科技项目(2022-ZL-02)
出版年
2024
NETL
NSTL
万方数据