The earth - mud - water double - mode shield tunneling machine started smoothly in the loop of Chengdu hub

On the morning of Feb. 26, the shield construction ceremony of Zirui Tunnel was held at the construction site of Zirui Tunnel. With the issuance of the initial instruction, the cutter head of "Zirui", the largest diameter dual-mode shield tunneling machine in China, slowly turned. The shield construction of Zirui Tunnel started smoothly and entered the interval tunnel construction stage. The construction process of Chengdu Railway Hub Circle Line took a key step forward.

Zirui tunnel is the control joint project of the second line of the west ring line of Chengdu hub, which extends from south Chengdu to Hongpailou section. It is an important project to promote the railway bus transformation in Chengdu. The total length of the line is 1940 meters, among which the open-cut tunnel is 614 meters long and the shield tunnel is 1326 meters long. The Zirui Tunnel Project, as the last key link to realize the connection of the two loop lines of Chengdu hub, started construction in September 2019. After the completion of the initial shaft construction and the installation and commissioning of the shield machine unit, the project officially started on the morning of February 26. The project is scheduled to be completed by the end of 2022.

Zirui Tunnel Project is located in the downtown area of Chengdu, under the subway station, municipal underground pipeline, viaduct, railway line, river and other different areas, the surrounding environment is complex, settlement control is strict, the project is difficult. According to the geological and hydrological conditions and surrounding environment of Zirui Tunnel, the construction unit has organized and carried out key technology research and breakthrough, and custom-made the largest diameter soil pressure and mud-water dual-mode shield machine "Zirui" in China, which was officially put off the production line on December 18, 2020, providing a strong guarantee for the smooth development of the project.

After the completion of the Zirui Tunnel, it will connect Chengdu Railway Station, Chengdu East Railway Station, Chengdu South Railway Station and Chengdu West Railway Station, realizing the double loop train operation of Chengdu railway hub, and further weaving the city railway bus operation line network. After the circular bus operation, the production factors and resource circulation are more optimized, the urban commuting efficiency is effectively improved, and the integrated travel of citizens is more convenient, injecting strong impetus to the economic complementarity and integration development of Chengdu Plain Economic Zone.