'CREC 977', a super-large diameter (12.2m) Earth Pressure Balance Machine (EPBM) exported from China to Europe, will be used in the construction of Italy's Naples-Bari high-speed railway project ('the Project'). So far, it is the largest EPBM exported from China to Europe.
The tunnel of the Project has a length of 12.8km, minimum turning radius of 2,000m and maximum slope of 12‰. Upon completion, it will be an main railway that connects Bari on the east coast and Naples on the west coast. According to the preliminary survey, methane and other combustible gases are widely distributed along the tunnel axis. This sets high requirements for explosion-proof safety during the construction, and adds difficulty to construction equipment design. It is also not easy for TBM construction, as the maximum buried depth of the tunnel is 400m and the maximum stratum pressure is 8bar.