In a significant development for the Mumbai-Ahmedabad High-Speed Rail Corridor, the National High Speed Rail Corporation Limited (NHSRCL) has signed a contract with M/s Afcons Infrastructure Limited for the construction of a 21 km long tunnel, including India's first-ever 7 km long undersea rail tunnel. This project falls under the MAHSR C-2 package in the state of Maharashtra.
The construction of the 21 km tunnel, particularly the creation of India's first twin-track undersea rail tunnel spanning 7 km across Thane Creek, poses significant challenges. To accomplish this feat, the project will utilise three Tunnel Boring Machines (TBMs) and the New Austrian Tunnelling Method.
Tunnel Specifications and Route
The tunnel will connect the underground station at Bandra-Kurla Complex to Shilphata in Maharashtra. It will consist of a single tube tunnel accommodating twin tracks for both up and down traffic. The project also includes the construction of 39 equipment rooms at 37 locations near the tunnel. The approximately 7 km undersea tunnel will be situated in the Intertidal Zone of Thane Creek.
Tunnelling Methods and Equipment
Tunnel Boring Machines (TBMs) with a cutter head diameter of 13.1 meters will be employed for excavation, as opposed to the more commonly used 5-6 meter diameter cutter heads for urban tunnels. Approximately 16 km of the tunnel will be excavated using three TBMs, while the remaining 5 km will be constructed using the New Austrian Tunnelling Method (NATM). The tunnel's depth will range from 25 to 65 meters below ground level.
To facilitate construction, several shafts and portals will be established. Three shafts will be located at the Bandra-Kurla Complex, Vikhroli, and Sawli at varying depths. Additionally, an inclined shaft at Ghansoli and a tunnel portal at Shilphata will aid in the construction of a portion of the tunnel using the NATM tunnelling method.
Tender Status and Future Developments
The contract agreement for the Mumbai HSR Station (MAHSR Package C-1) was signed on March 20, 2023. The contract for the construction of the tunnel between Mumbai HSR Station and Shilphata (approximately 21 km) under MAHSR Package C-2 was finalized on May 8, 2023. Technical bids for civil and building works, including the construction of three stations at Thane, Virar, and Boisar, between Shilphata and Zaroli village on the Gujarat-Maharashtra border (135 km) under MAHSR Package C-3, were opened on April 12, 2023.
Revolutionising Transportation in India
The development of the Mumbai-Ahmedabad High-Speed Rail Corridor is set to revolutionize transportation in India by providing a faster and more efficient means of travel between the two major cities.
