NEW DELHI: The National High Speed Rail Corporation Ltd (NHSRCL) has invited bids for the tunneling works for 21 km-long (approx) tunnel including a 7-km undersea tunnel using Tunnel Boring Machine (TBM) and New Austrian Tunneling Method (NATM) for the Mumbai-Ahmedabad High Speed Rail corridor.
According to a statement released here, the tunnel will be between the underground station at Bandra-Kurla Complex and Shilphata in Maharashtra. The 7 km undersea tunnel at Thane Creek will be the first undersea tunnel to come up in the country. The tunnel will be a single tube tunnel to accommodate a twin track for both up and down track.
The statement further reads that 39 equipment rooms at 37 locations will also be constructed in adjoining tunnel locations as part of the package. To construct this tunnel, TBMs with a cutter head of 13.1 metre diametre will be used. Usually, 5-6 metre diameter cutter heads are used for urban tunnels used in MRTS-Metro systems.
Three Tunnel Boring Machines will be used to make about 16 km of the tunnel portion and the remaining 5 km will be through New Austrian Tunnelling Method (NATM), reads the statement.
It is also informed that this tunnel will be about 25 to 65 metres deep from the ground level and the deepest construction point will be 114 metres below the Parsik Hill near Shilphata. Three shafts at BKC (under package C1), Vikhroli, and Sawli at approximate depths of 36, 56 and 39 metres, respectively will facilitate the construction. The inclined Shaft of 42 metre at Ghansoli and the Tunnel portal at Shilphata will facilitate the construction of approx 5 km of the tunnel through the NATM tunnelling method.
The bid submission end date for the C2 package is January 19, 2023. The bids for the design and construction of the underground Bandra Kurla Complex high speed rail station including cut and cover length of 467 metre and ventilation Shaft of 66 metres in Mumbai, Maharashtra, under C1 package floated on July 22, 2022 and bids submission end date is October 20, 2022. (ANI)