ABSTRACT
For Tuen Mun Chek Lap Kok Link subsea tunnels construction, numerous innovative solutions were implemented to overcome the challenging ground conditions and the surrounding pressure higher than 5 bars at tunnel face. Two 14m diameter TBMs were used along the 4.5km long drive below the sea. One of them had started its drive with the world’s largest diameter (17.63m) along the first 630m before being reconfigured into a 14m diameter TBM. For cutting tools replacement, saturation diving system and full automatic robotic arms were developed to change a total of about 2000 disc-cutters on both TBM cutterheads. Another major challenge was the construction of 41 subsea cross passages between tunnels for which the pipe jacking methodology was adapted for the project. Apart from TBM drives, innovative design solutions were developed for the construction of Shafts and Cut and Cover sections including a 500m-long and 43m-deep Caterpillar-shaped cofferdam with 15 cells.
