摘要
麻科义隧道是蒙华铁路的重难点控制性工程,在隧道进口端存在长约135 m的砂层段,易出现拱部砂层垮塌严重、掌子面溜塌、围岩变形较大从而发生坍塌等事故,施工难度极大.本文分析了砂层段的地质情况及施工中面临的主要困难,通过工程实践和监控量测数据进行分析研究.研究结果表明,在该种地层中采用三台阶预留核心土法和松动爆破、合理设置支护参数及预留变形量、严格控制安全步距、加强监控量测等措施,是保证大断面砂层隧道安全施工的关键,可对其他类似工程施工提供一定的工程经验.
The Makeyi Tunnel is a controlling project with difficulty of Menghua Railway. There is a sand layer section with a length of about 135 m at the inlet end of the tunnel. The sand layer of the arch is likely to collapse, the face of tunnel is easy to slide down, and the deformation of the surrouncling rock is large, leading extreme difficulties in construction. In this paper, the author analyzed the geological conditions of the sand layer and the main difficulties in construction. The research results showed that these were the key points to ensure the safety of the large-section sand tunnel in aspects of the three steps reserving the core soil, the loose blasting, reasonable support parameters and the reserved deformation, the strictly controlled safety step, the enhanced monitoring and measurement, etc. These would be valuable engineering experience for other similar projects.
作者
申运涛
谢江胜
Shen Yuntao;Xie Jiangsheng(China Railway 20th Bureau Group Co. Ltd., Xi’an Shaanxi 710016, China)
出处
《铁道建筑技术》
2019年第9期128-131,150,共5页
Railway Construction Technology
基金
中铁二十局集团有限公司科技研发项目(YF1600SD03B)
关键词
砂层段
预留核心土
松动爆破
超前支护
监控量测
sand layer section
reserved core soil
loose blasting
advance support
monitoring measurement