Mumbai: The technical bids for the construction of a 21km tunnel, 7km of which will be under the sea, as part of the Mumbai-Ahmedabad High Speed Rail Corridor, popularly called the Bullet train project, was opened on Thursday.
Two bids have been received from Afcons Infrastructure Limited and Larsen & Toubro Limited for the C-2 package between Bandra-Kurla Complex in Mumbai and Shilphata in Thane, a National High Speed Rail Corporation Limited (NHSRCL) spokesperson said. After technical evaluation, financial bids will be opened.
Single-tube twin-track structure tunnel
As per NHSRCL, the tunnel will be a single-tube twin-track structure with a diameter of 13.1mt at depths ranging from 25-40 metres below the ground. Of its 20.37km length, three tunnel boring machines (TBMs) will build 15.42km of the structure, while the remaining 4.96km stretch will see the work being done as per the New Austrian Tunnelling Method (NATM).
“The tunnel will cross Thane creek and the survey work under the creek was done using underwater static refraction technique and was successfully completed. The NHSRCL has showcased facade designs of Bandra Kurla Complex, Virar, Boisar, and Thane stations in Maharashtra,” an official said.