北京铁路直径线大断面地下隧道盾构机选型研究

 拟建的北京站和北京西站之间直径线可使北京铁路枢纽布局更为完善，直径线地下隧道拟采用盾构法施工，盾构机选型是盾构法施工的关键环节之一。分析直径线地下隧道穿越地层的地质条件和水文条件，给出盾构机选型的一般程序和依据，着重分析工程地质条件对盾构选型的影响，对不同类型盾构的施工风险进行评估。主要研究结论是：泥水平衡盾构在控制地表沉降、漂石卵石处理、掘进进度、减少刀盘刀具磨损及开仓换刀次数等方面均优于土压平衡盾构；本工程具备泥水处理装置的场地布置条件，弃浆、降低施工噪声等环境保护问题也可得到较好地解决；本工程适于采用泥水平衡盾构机。

Type Selection of Shield Machines for Large Cross-section Underground Railway Tunnel on Straight Rail Transit Line in Beijing

he proposed straight rail transit line form Beijing Railway Station to Beijing West Railway Station can make the layout of Beijing railway terminals more reasonable. The tunnel on the straight rail transit line is to be constructed by shield machines. The type selection of the shield machines is one of the critical stages of the execution of the project. This paper analyzes the geology and hydrogeology conditions of the underground tunnel on Beijing Straight Rail Transit Line, presents the general procedures of and basis for the type selection of shield machines, and stresses the influence of the engineering geology conditions on the type selection of shield machines and evaluations on construction risks of various types of shield machines. The major research conclusions are as follows: slurry shield machines are superior to EPB shield machines in respect of surface subsidence control, boulder/cobble coping, advance speed, reduction in cutting tool wear and numbers of chamber opening for exchange of cutting tools; this project has proper site areas for the installation of the slurry treatment facilities and the problems related with the environment protection, such as disposing of waste slurries and reduction of construction noises, can be well resolved; slurry shield machines are suitable for this project.