CHENNAI: The Tunnel Boring Machine (TBM) 'Nilagiri' completed its breakthrough at the Moolakadai north shaft on Wednesday, marking the successful completion of an 819-metre underground tunnel on the up line between Madhavaram High Road Station and Moolakadai Station, forming part of corridor 3, which stretches from Madhavaram Milk Colony to Kellys.
The tunnelling work is being executed by Tata Projects Limited, which has deployed seven Tunnel Boring Machines (TBMs) for the first 9 km underground section of the corridor. This achievement represents the 11th TBM breakthrough.
With this accomplishment, CMRL has now completed 24 TBM breakthroughs under Phase 2, which spans 118.9 kilometres across three Metro corridors designed to enhance Chennai's urban transportation network.
The tunnel section between Madhavaram High Road and Moolakadai posed significant engineering challenges, as per the Chennai Metro Rail officials.
"During excavation, the TBM successfully passed beneath the Buckingham Canal and a busy traffic corridor while safely managing the presence of more than 14 bore wells along the alignment. Alternate water supply arrangements were provided to ensure uninterrupted public service throughout the construction period," said the official press note.
CMRL stated that the entire tunnel drive was completed within permissible ground settlement limits through extensive instrumentation and continuous monitoring, ensuring public safety and structural stability during construction.