Abstract:

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.

Key words: large cross-section underground railway tunnel  , straight rail transit line  , shield machine  , type selection slurry shield machine  , EPB shield machine