Tunnel Boring Machine (TBM) Xihe has completed excavation of the up-track tunnel to the future Tung Chung West Station and has begun boring the down-track tunnel towards Tung Chung Station.
The move marks a significant construction milestone for MTR Corporation’s Tung Chung Line Extension project in Hong Kong.
The Tung Chung Line Extension is described as a strategic rail scheme designed to facilitate the long-term development of Lantau.
The project involves constructing two additional stations – Tung Chung West and Tung Chung East – and around 1.3km of new twin-bore tunnels that will lengthen the existing Tung Chung Line.
Tunnelling works are being carried out by a joint venture between Bouygues Travaux Publics and Dragages Hong Kong.
The TBM, manufactured by Herrenknecht, has a diameter of roughly 7.3m, is about 100m long and weighs around 1,000t.
Under more conventional procedures, a TBM would typically be dismantled, transported to a separate launching shaft and reassembled.
In this case, after detailed planning and calculations, the team adopted the push-pull method together with a Self-Propelled Modular Transporter to rotate and reassemble the machine within the shaft in stages, once the up-track tunnel to Tung Chung West Station’s shaft had been completed, in readiness for down-track excavation.
“This is the first time a TBM U-turn operation has been conducted in an MTR new railway project,” MTR Corporation said.
Following the U-turn, Xihe underwent full inspection and maintenance before commencing the down-track drive towards Tung Chung Station.
MTR Corporation added that the project team will continue to press ahead with the remaining tunnelling, aiming to finish the second tunnel by 2026.
