CHENNAI: The Chennai Metro Rail Limited (CMRL) on Friday began the second tunnelling drive between Thirumayilai and Boat Club stations as part of the underground section of Corridor-4 under the Phase II project.
The tunnel boring machine ‘Eagle’ has begun its work from Tirumayilai station and will excavate a 2,274-metre-long tunnel towards Boat Club station. The tunnelling alignment includes drag-through operations at Alwarpet and Bharathidasan metro stations, allowing the machine to continue its journey without being dismantled.
The drive also includes a 586-metre fully stacked tunnel section between Alwarpet and Bharathidasan stations, where the machine will pass through a complex underground alignment. According to CMRL, the drive will pass through mixed geological conditions, with soft alluvial soil in the upper layers and hard rock below, requiring continuous monitoring to maintain ground stability and tunnel alignment.