On February 3 (the 6th day of the Lunar New Year), the Hanoi Urban Railway Management Board (MRB), together with the consulting unit and contractor, started drilling the tunnel using the second TBM (Tunnel Boring Machine) named "Bold" for the underground section of the Nhon - Hanoi Station metro project.
Previously, the first TBM named “Than Thuong” started drilling the tunnel on July 30, 2024. To date, the first TBM of the project has drilled 985m of tunnel.
In fact, the fact that the TBM “Bold” has only now begun its tunneling mission is behind schedule. According to the previous plan, when the TBM “Speed” drilled 240m (around September 2024), the TBM “Bold” would be started. However, at that time, the TBM “Speed” encountered obstacles during the drilling process.
“The first TBM encountered very complicated geological problems, the gravel layer was harder than expected... At this time, the machine's parameters had to be continuously adjusted and the speed reduced. At that time, the contractor decided to let the first machine continue drilling to collect complete geological data, as a basis for adjusting the second TBM, ensuring the second TBM's operation was smoother and more effective,” said Mr. Nguyen Ba Son - Deputy Head of the Hanoi Urban Railway Management Board.
According to Mr. Son, after changing the parameters to suit the geological situation, the “Speed” TBM has now reached a speed of 18m/day (the previous plan was about 10-12m/day). It is expected that by the end of 2025, both tunnels of the Nhon - Hanoi Railway Station metro project will complete drilling and move on to the next phase.
Regarding the construction progress of the 4km underground section of the Nhon - Hanoi station metro project, up to now, the tunnel and underground stations have reached 53.46%; the underground ramp has been completed 75.66%; station S9 has been completed 50.48%; the vertical shaft has been completed 24.09%; the tunnel has reached 47.41%; stations S10, S11, S12 (including lane change and garage) have been completed 64.44%, 58.1%, 58.4% respectively.
“During the excavation process of the first TBM, we supplied more air to the compression chamber and reduced the amount of soil and rock in the chamber to balance the pressure, while performing other difficult techniques to get the first TBM through the complex geological area. We are completely confident that we can achieve the desired progress when starting the second TBM,” informed Mr. Park Young Ill - Project Director, Hyundai & Ghella Joint Venture.
It is expected that the underground section of the Nhon - Hanoi Railway Station metro project will be completed and put into operation in 2027.
