BENGALURU: China will play a role in putting in place the infrastructure for Namma Metro’s Phase-II. The contract to supply four Tunnel Boring Machines (TBMs) for the underground section from Vellara Junction to Pottery Town is all set to be given to China Railway Construction Heavy Industry Corporation Limited (CRCHI), said sources.
The 5.5km underground stretch is part of the 13 km underground corridor of the Nagavara-Gottigere Line. While the six TBMs for Bangalore Metro Rail Corporation’s Phase-I underground corridor were purchased from Japan, Germany, US and Italy, Phase-II will mark the debut of a Chinese firm, said a source. “CRCHI is a global name in TBMs and make nearly 300 of them annually,” he added.
Larsen and Toubro Limited has been awarded the contracts for two out of four packages on the Gottigere Line: Vellara Junction to Shivaji Nagar (Package 2) for Rs 1329 crore and Shivaji Nagar to Pottery Town (Package 3) for Rs 1299 crore. The China-built TBMs will be deployed for both these packages. “Each TBM will cost anywhere between Rs 70 and Rs 75 crore. They will be shipped from China to our nearest port, mostly Chennai,” the source added.
They are almost similar to the two machines shipped from Japan for Phase I, which were instrumental in carrying out tunnelling work between Kempegowda and Cubbon Road Metro stations. The breakdown of Godavari TBM, which delayed Phase-I project by more than a year, is not likely to be repeated.
“A few spare parts are also being purchased along with the TBMs so that any problems can be set right immediately without waiting for them to arrive from abroad,” the source said. Explaining the proposed tunnelling plan as of now, another source said that the stretch has five stations-Vellara Junction, M G Road, Shivaji Nagar, Bamboo Bazaar and Pottery Town. “The machines will carry out boring work from one end to its first point, from Vellara Junction to MG Road. The machines will then be dismantled and brought to the surface so that the M G Road station can be put in place.
A similar procedure will be carried out from the other end, from Pottery Town towards Bamboo Bazaar,” he said.
After each station, a vertical shaft will be created to bring the machine up to the ground level. “While contractors for Chennai and Jaipur Metro have carried out underground tunnelling for the entire stretch, it will be done only in phases for Bangalore Metro. Doing it at one stretch would increase costs enormously,” the source said.