L&T's 12.19m-diameter tunnel boring machine (TBM) Mavala excavated 456.72 metres in a single month on the Mumbai Coastal Road Project (MCRP) Package 4.
Launched from Girgaon Chowpatty, the TBM, currently the largest at work in India, broke the previous world record of 455.4 metres for monthly tunnelling done by a 13m single-shield earth pressure balance TBM.
L&T director and senior executive VP for civil infrastructure, SV Desai, said: “This is a huge achievement for the entire construction industry worldwide and truly an engineering feat to be proud of.
“We achieved this speed of tunnelling thanks to our experienced and qualified team. It had given us a huge boost to speed up construction to deliver this iconic and extremely complex project in time and with quality,” he added.
Mavala, built by the China Railway Construction Heavy Industry Company, was delivered to site at the height of the Covid-19 pandemic and as the Chinese technicians were unable to travel, L&T’s site team had to assemble the machine themselves with only ‘virtual’ help from the manufacturer.
Phase 1 of the MCRP is a 9.98km section from Princess Street Flyover at Marine Lines to the Worli end of the Bandra-Worli Sea Link (BWSL).
L&T has the contract for two of the three work packages on Phase 1.
Package 1 involves the construction of a 3.82km-long section over reclaimed land from Priyadarshini Park to Baroda Palace with interchanges at Amarson Garden and Haji Ali.
Its second package (confusingly, Package 4) involves the construction of a two-kilometre twin-bored tunnel along with cut-and-cover section to form a combined road length of 4.06km. When completed, this section will be the largest and deepest bored road tunnel in India.