以新建兰渝铁路木寨岭隧道为例,在现场工程实践的基础上,着重对单线铁路隧道Ⅳ~Ⅴ级软弱围岩地段三台阶法快速施工的施工工序、施工工艺、劳动组织及量测指导施工等进行了阐述,并对三台阶法在软岩隧道应用中的一些注意事项进行了分析,以期能为今后同类工程提供参考和借鉴。 Taking the Muzhailing Tunnel of Lanzhou-Chongqing Railway as an example, on the basis of on-site engineering practice, the construction procedure, construction technology, labor organization and measurement of rapid construction of Grade IV ~ V soft surrounding rock mass of single-line railway tunnel are emphasized. Guidance and construction were elaborated, and some considerations in the application of the three steps method in soft rock tunnel were analyzed in the hope of providing reference and reference for similar projects in the future.