The tunnel boring machine (TBM) of Lucknow Metro Rail Corporation (LMRC) started its first tunneling drive in front of Bapu Bhavan underground Metro station site in the presence of the LMRC managing director and other senior officials on Monday.
The underground tunneling work for the 3.5 km Sachivalaya, Hussainganj and Hazratganj section of Phase 1 A (North – South Corridor) of Lucknow Metro Rail Project has started ahead of schedule.
LMRC officials said on condition of anonymity that work would be carried out simultaneously on the up and down lines with two tunnel boring machines (TBMs) aptly named ‘Gomti’ and ‘Ganga’, after the two prominent rivers in the state.
Both the TBMs were brought by road from Delhi to Lucknow in parts with each TBM requiring 24 low bed multi-axle trailers for transportation. Prior route survey and necessary mitigation measures in identified problematic stretches were undertaken in advance to ensure safe passage of trailers particularly through busy and congested areas, toll plazas and bridges.
While the first TBM ‘Gomti’, which was assembled 18 m deep inside the launching shaft at the Bapu Bhavan station, commenced operations for the UP line, the second TBM ‘Ganga’ is in an advanced stage of assembling and is scheduled to commence tunneling on down line in the first week of March. Assembly of TBMs is a complex technical process involving lowering of individual parts down the shaft by 250 tonne crane, correct positioning, jointing and providing electrical/hydraulic/water/grouting connections.
The completion of assembly of first TBM took just 8 months from the time of award of contract to M/s Gulermak -TPL JV, which is a record in itself since this process normally takes about a year. This became possible only due to meticulous planning and execution of parallel works by LMRC engineers and the executing agency, said a higher LMRC official.