Chennai Metro's TBM S81B Achieves Breakthrough
RAILWAYS & METRO RAIL

Chennai Metro's TBM S81B Achieves Breakthrough

Tata Projects Ltd. achieved another milestone as TBM S81 B, nicknamed Kolli, made a breakthrough at Otteri station on Line 3 of the 116.1km Chennai Metro Phase 2. In July 2023, Tata Projects had deployed TBM Kolli on the south shaft of Ayanavaram Station on the 45.8km Line 3 (Mandharam station to Siruseri SIPCOT). After covering approximately 903m, TBM Kolli reached Otteri station within 13 months.

Kolli, a Terratec Earth Pressure Balance (EPB) machine, with a 06.61km reach, faced over 100 bore wells during excavation and had to navigate two sharp curves with radii of 220m and 280m to avoid disruptions.

Previously, TBM S18, after its first breakthrough in Pune Metro, passed its Factory Acceptance Test (FAT) in December 2022 before being deployed in Chennai Metro Phase 2. The current task involving TBM Kolli falls under Package TU-01, which was awarded to Tata Projects by Chennai Metro Rail Ltd. (CMRL) in May 2021 with a 42-month deadline. The total cost of the project is ?1999 crore.

Package TU-01 covers a 9km section on Line 3 of Chennai Metro Phase 2. TBM Kolli, along with six other TBMs under this package, is tasked with constructing a 9km twin tunnel (totalling 18km) from the TBM retrieval shaft near Venugopal (Line 5) to Kelly station (Line 3) and constructing diaphragm walls and entry and exit structures at four stations. So far, Tata Projects Ltd. has recorded six tunnel breakthroughs under Package TU-01.

Tata Projects Ltd. achieved another milestone as TBM S81 B, nicknamed Kolli, made a breakthrough at Otteri station on Line 3 of the 116.1km Chennai Metro Phase 2. In July 2023, Tata Projects had deployed TBM Kolli on the south shaft of Ayanavaram Station on the 45.8km Line 3 (Mandharam station to Siruseri SIPCOT). After covering approximately 903m, TBM Kolli reached Otteri station within 13 months. Kolli, a Terratec Earth Pressure Balance (EPB) machine, with a 06.61km reach, faced over 100 bore wells during excavation and had to navigate two sharp curves with radii of 220m and 280m to avoid disruptions. Previously, TBM S18, after its first breakthrough in Pune Metro, passed its Factory Acceptance Test (FAT) in December 2022 before being deployed in Chennai Metro Phase 2. The current task involving TBM Kolli falls under Package TU-01, which was awarded to Tata Projects by Chennai Metro Rail Ltd. (CMRL) in May 2021 with a 42-month deadline. The total cost of the project is ?1999 crore. Package TU-01 covers a 9km section on Line 3 of Chennai Metro Phase 2. TBM Kolli, along with six other TBMs under this package, is tasked with constructing a 9km twin tunnel (totalling 18km) from the TBM retrieval shaft near Venugopal (Line 5) to Kelly station (Line 3) and constructing diaphragm walls and entry and exit structures at four stations. So far, Tata Projects Ltd. has recorded six tunnel breakthroughs under Package TU-01.

Next Story
Infrastructure Urban

DCPC Prepares for Special Campaign 5.0 with Focus on E-Waste

The Department of Chemicals and Petrochemicals (DCPC), Ministry of Chemicals and Fertilisers, is gearing up for Special Campaign 5.0, to be held from 2nd to 31st October 2025. The initiative will focus on e-waste disposal as per MoEFCC’s E-Waste Management Rules 2022, space optimisation, and enhancing workplace efficiency across field offices.Special Campaign 4.0, conducted between October 2023 and October 2024, delivered notable results in record management, grievance redressal, scrap disposal, and cleanliness drives.Key outcomes of Special Campaign 4.0Records management: 2,443 physical fil..

Next Story
Real Estate

BlackRock India Leases 1.4 Lakh Sq Ft in Bengaluru

BlackRock Services India, the domestic arm of global asset manager BlackRock, has leased 1.4 lakh sq ft of office space at IndiQube Symphony in Bengaluru, according to Propstack data. The 10-year deal is valued at around Rs 4.10 billion.The lease, among the largest transactions in India’s co-working sector, highlights the growing preference of global institutions for flexible office providers. The agreement, commencing October 1, 2025, covers ground plus five floors in KNG Tower 1 at Ashoknagar, MG Road — one of Bengaluru’s prime commercial hubs.As per the lease document, BlackRock will ..

Next Story
Infrastructure Transport

L&T Bags Rs 25–50 Bn Order for Mumbai-Ahmedabad Bullet Train Track Works

Larsen & Toubro’s (L&T) Transportation Infrastructure business has secured an order valued between Rs 25 crore and Rs 50 billion from the National High Speed Rail Corporation Limited (NHSRCL) for the Mumbai-Ahmedabad High Speed Rail (MAHSR) corridor.The contract, Package T1, involves the design, supply, construction, testing, and commissioning of 156 route km of high-speed ballastless track on a Design-Build Lump Sum Price basis. The stretch runs from Mumbai’s Bandra-Kurla Complex to Zaroli village in Gujarat and includes 21 km of underground track and 135 km of elevated viaduct.Se..

Advertisement

Subscribe to Our Newsletter

Get daily newsletters around different themes from Construction world.

STAY CONNECTED

Advertisement

Advertisement

Advertisement

Talk to us?