Press release - On July 15th, the Guangzhou Haizhu Bay Tunnel project achieved a significant milestone with the successful breakthrough of both tunnel lines. This project marks the construction of the first super-large diameter municipal Tunnel Boring Machine (TBM) tunnel in the Pearl River Basin.
Guangzhou Haizhu Bay Tunnel
The tunnel was constructed using the "Pioneer," a super-large diameter slurry TBM developed by China Railway Construction Heavy Industry Corporation Limited (CRCHI). The "Pioneer" completed the project ahead of schedule.
Earlier, on July 6th the tunnel connecting passage TBM, precisely entered the receiving sleeve, marking the successful completion of the first connecting passage of the Guangzhou Haizhu Bay Tunnel project. This was a high-precision breakthrough and represents the first engineering application of a super-large diameter TBM for tunnel connecting passages in China. The TBM, produced by CRCHI, features an excavation diameter of 3,860 mm.
The Haizhu Bay Tunnel project is the first super-large diameter TBM tunnel in Guangzhou, earning it the title of the "Largest TBM tunnel in Guangzhou." The route spans a total length of 4.35 kilometres, with 2,102 meters dedicated to the TBM section. During construction, the TBM needed to traverse a fracture zone and the Pearl River Channel twice and pass through mudstone, muddy siltstone formations, and beneath a complex array of buildings and piles. This challenging construction environment necessitated stringent requirements for the TBM, when considering the multiple tunnelling control factors and high construction difficulties. The total length of the six connecting passages ranges from 14.8 meters to 18.1 meters. The main tunnel segments are C60 high-strength segments, with the connecting passage buried more than 45 meters deep and at a significant angle to the main tunnel. The connecting passage TBM required concurrent and intersecting construction with the main tunnel TBM.
The "Pioneer" Slurry TBM, with an excavation diameter of 15.07 meters, a total length of 130 meters, and a total weight of 4,300 tons, was assembled in February 20, 2023. All processes from assembly to launching were completed in under three months. The launch date was two months later than the TBM for the western line, but the eastern line was completed in 12 months, one month earlier than the western line. During tunnelling, the "Pioneer" TBM achieved a maximum daily advance rate of 16 meters and a maximum monthly advance rate of 324 meters.
The tunnel connecting passage TBM employed several key technologies, including rapid breaking of oblique intersection lining, synchronous construction layout, high-pressure sealing, rapid posture adjustment, and high-precision guidance correction. It achieved the highest daily progress of two ring segments, completed the oblique breaking of the C60 high-strength segments in less than three hours, and set a new record for cutting the main line tunnel segments.
The total investment for the Haizhu Bay Tunnel project is approximately 11.68 billion yuan. Once completed, the Haizhu Bay Tunnel will reduce driving time from downtown Guangzhou to Guangzhou South Railway Station to just 15 minutes. The tunnel is scheduled to open to traffic in 2025.
For further information about CRCHI please visit their website https://en.crchi.com/ and also the tunnelbuilder archive here.
