Tunnel connection of Jinyong Railway
On March 19th, the Jinhua Ningbo Railway, a national key project constructed by China Railway Fifth Bureau under China Railway Corporation, was newly constructed.
Baocun Tunnel has various types of surrounding rock, and the Cathaysian geological structure in the tunnel site area is relatively developed. There are a total of 6 faults, 2 rock vein intrusion contact zones, and 9 joint dense zones, with 9 penetrating reservoirs or streams. It is evaluated as a high-risk tunnel, and there are many difficulties in construction, such as large water inflow, high ground temperature, high ground stress, and rock burst.
In response to issues such as high safety risks and difficult excavation, China Railway Fifth Bureau has scientifically organized and meticulously constructed, consistently adhered to "high standards and strict requirements", and continuously strengthened the entire process control; Adhering to the policy of "safety first, prevention first", ensure the construction safety, stability, and controllability by strengthening advanced pre-support and dedicated personnel on duty monitoring; Supply ice cubes 24 hours a day, install 8 sets of jet fans on 4 sets of secondary lining trolleys, and equip them with sprinklers to achieve temperature reduction and dust reduction, effectively improving the on-site working environment. The Baocun Tunnel, the last ten thousand meter tunnel along the entire line, has been successfully completed. By now, 45 tunnels along the Jinyong Railway have been completed, laying a solid foundation for the opening and operation conditions at the end of the year.
Jinyong Railway is the first pilot line for the transportation of double layer high container containers in China. The newly built main line has a total length of about 188.3 kilometers. It is a Class I electrified railway with dual passenger and freight lines, with a design operating speed of 160 kilometers per hour and a reserved speed of 200 kilometers per hour. Baocun Tunnel is a key and difficult control project of Jinyong Railway, with a total length of 10360 meters, double track and single tunnel, and a maximum buried depth of 512 meters. The exit section is designed for a large span of a three track railway.