Double breakthrough after challenging drive in India 28 Jun 2018

Two 6.52m diameter Earth Pressure Balance machines broke through simultaneously at Lucknow Hussainganj underground metro station to complete tunnelling on phase 1A of the Lucknow Metro in India for the Gulermak-TATA Projects JV.

Gulermak-TATA Projects JV celebrate breakthrough

The double breakthrough by the EPBMs from Terratec at the end of April 2018 completed the third drives of the contract two months ahead of schedule and marked completion of tunnelling works on the 3.67km long Charbagh-Hazratganj underground stretch in approximately 15 months.

Officials from Terratec, Gulermak-TATA Projects JV and the Lucknow Metro Rail Corporation (LMRC) celebrated completion of the city’s first TBM-driven tunnels as part of the 22.88km-long (Phase 1A) Lucknow Metro North-South line.

The TBMs excavated through geology consisting of stiff to hard clayey silt and medium to dense silty sand, passing beneath historic buildings in the Capital Plaza of Azratganj (heritage district) without any disturbance to buildings, public utilities or traffic.

The EPB machines have a classic soil configuration with a spoke-style cutterhead and a 57% opening ratio. The cutting tools were designed to be interchangeable with 17in roller disc cutters, allowing the TBMs to bore through station diaphragm walls and cope with the presence of unexpected obstacles in the ground.

The final drives from Charbagh to Hussainganj were particularly challenging as the TBMs had to pass 1m below the bed of the Haider Nallah canal in a highly populated area full of dilapidated structures on weak foundations.

Terratec has supplied 22 machines in five years

"The TBMs delivered excellent performance, with no major breakdowns, crossing the Haider Nallah and so many other geological challenges along the way,” said Ramesh K, Assistant General Manager (P&M) with TATA Projects.

These tunnels will now provide Lucknow, the capital of Uttar Pradesh, with its first underground metro line, bringing a modern public transportation system to a city that is currently experiencing rapid population growth and substantial traffic congestion. Phase 2 of the system is due to start construction later this year.

Larsen and Toubro will launch the first of two Terratec 6.57m diameter EPBMs for the East-West Package 2 contract on the 20.7km long Line 1 of the Ahmedabad Metro in western India, awarded by Metro-Link Express for Gandhinagar and Ahmedabad (MEGA) Company.

The contract includes construction of 3.3km of twin tube running tunnels between Kalupur Railway Station and Shahpur, two underground stations at Gheekanta and Shahpur, and cut and cover structures, NATM connections and launch and retrieval shafts for the TBMs.

The first of the two TBMs is due to be launched in the coming days from a launch shaft located at Kalupur Station, with the second expected to follow sometime this June. The tunnelling works are due to be complete by December 2019.

Terratec has supplied 22 TBMs to the Indian market in the last five years, all tailor made, robust and with specialist support onsite.