On September 15, the super-large diameter slurry TBM developed by CREG completed factory acceptance in Zhengzhou. The TBM will be deployed for tunnel construction of the Hefei G4001 Link Project (hereinafter referred to as the West Extension Project of North Second Ring Road), which runs beneath Dongpu Reservoir, injecting strong impetus into Hefei’s urbanization drive.
Lot 1 of this project starts from the interchange of West Second Ring Road and Qingxi Road in the east and extends to Kexuedao Road in the west, with a total length of approximately 3.8 kilometers and dual 8-lane carriageways. Its core controlling work, the tunnel section crossing underneath Dongpu Reservoir, stretches about 2.9 kilometers. Adopting a twin-tube double-deck structural design, this project represents a rare case in China where a super-large diameter shield machine bores beneath a major reservoir serving both flood control and water supply.
To tackle the extreme construction challenges of the project, this super-large diameter slurry TBM leverages cutting-edge technologies to resolve key pain points in underwater tunnel construction.
Impressive Super-large Dimensions
The machine features an excavation diameter of 16.68 meters, an overall length of 125 meters and a total weight of around 4,800 tonnes, earning it the reputation of a genuine "underground giant".
Atmospheric Cutter Replacement, Safe and Efficient
Equipped with an accessible cutterhead system, it enables cutter replacement under atmospheric pressure under a high water pressure of 8 bar. This completely eliminates risks associated with hyperbaric operations, balancing construction efficiency and personnel safety.
Intelligent Muck Discharge, Reinforcing Safety Barriers
Fitted with a dedicated circular muck discharge system, it adopts the advanced slurry treatment mode of "screw machine direct discharge + out-of-chamber crushing". The design not only ensures stable and efficient muck removal by slurry discharge pumps, but also removes safety hazards requiring personnel to enter the chamber for crusher maintenance, safeguarding the construction of extra-long underwater tunnels.
