First TBM breakthrough in Lucknow

11 October 2017

India - Crews celebrated breakthrough on the first TBM-driven tunnels in the capital of Uttar Pradesh. A Gulermak-Tata Projects JV was the contractor for the project, which is part of the 22,88km Phase 1A of the Lucknow Metro North-South Line.

A 6.52m Terratec TBM was used for the 3.44km down-line drive, which completed in May but broke through in August after a wait for the official ceremony, according to the manufacturer. A few days later, the identical up-line TBM broke through.

The TBMs mined through geology consisting of stiff to hard clayey silt and medium to dense silty sand, passing beneath historic buildings in the Capital Plaza of Hazratganj (heritage district) without any notable disturbance.

A spokesperson for the manufacturer said: “The EPB machines feature a classic soil configuration and are equipped with a spoke-style cutterhead with a 57 percent opening ratio. TERRATEC has designed the cutterheads with cutting tools that are interchangeable with 17’’ roller disc cutters, allowing the TBMs to bore through station D-walls and cope with the presence of any unexpected obstacles in the ground.”

LMRC’s Managing Director, Mr. Kumar Keshav said: "This achievement was only possible due to the hard work and commitment of the Lucknow Metro project team. The tunnelling in this stretch posed an enormous technical challenge as the route passes beneath highly congested areas at a depth of 12 to 15m below ground. With this breakthrough, LMRC has achieved one of the biggest milestones in form of completion of first TBM drive in the construction of underground metro in the state of Uttar Pradesh."

Tata Projects MD Vinayak Deshpande added: "Due to many heritage structures, the stretch was highly challenging. With excellent guidance from the LMRC team, state-of-the-art TBMs, and a dedicated, passionate, project team, the daunting task was completed in a world-class manner with outstanding quality and before-time completion. We all at TATA projects feel very proud of this accomplishment.”