Australian tunnelling equipment manufacturer Terratec has reported two tunnelling milestones on Phase II of the Chennai Metro project in the Indian state of Tamil Nadu.
It marks progress on Line 3 and Corridor 5 in partnership with Tata Projects and Chennai Metro Rail (CMRL).
At Kolathur on Line 3, Terratec’s earth pressure balance machine (EPBM) is driving a tunnel from Kolathur Ramp to Kolathur Station.
The work is being carried out under what the project team describes as technically challenging conditions.
It includes a shallow overburden of 1.8m, a gradient of -3.8%, and excavation beneath a busy urban corridor.
These factors have required extensive ground-protection measures, noted the company.
In a separate development at Kolathur Station, another tunnel boring machine (TBM) supplied by Terratec has been launched for a drive towards Srinivasa Nagar.
This section of the alignment passes through mixed Grade-4 and Grade-5 rock and incorporates a tight 230m radius curve.
The launch of the new TBM coincided with a breakthrough by another machine at the same station, resulting in two TBM-related milestones occurring at once.
Project stakeholders report that progress so far is in line with expectations for both safety and engineering performance.
They note that community engagement and environmental management measures are in place to limit disruption in nearby residential areas, while maintaining what they describe as a strong safety record on site.
Phase II of the Chennai Metro is planned to add close to 119km of new track and about 128 additional stations, with the objective of easing traffic congestion.
Terratec, which supplies tunnel boring machines, raise boring rigs and microtunnelling systems, has previously provided equipment for metro schemes in Delhi, Lucknow, Pune and Mumbai.
