Daijiworld Media Network - Mumbai
Mumbai, Sep 19: The Mumbai-Ahmedabad High-Speed Rail Project is poised to achieve a significant milestone on September 20, with the final breakthrough of its NATM (New Austrian Tunnelling Method) tunnel in the Maharashtra section.
Unlike machine-driven tunnelling, NATM relies on the surrounding ground as natural support, with concrete sprayed on tunnel walls to stabilise the structure as work progresses. The Package C2, which includes this tunnel, is being executed by Afcons Infrastructure Ltd.
Bullet Train Corridor in Maharashtra
• Maharashtra section: 156 km of the total 508 km corridor
• Elevated track: 135 km between Shilphata and Zaroli (Maharashtra-Gujarat border)
• Tunnel section: 21 km starting from BKC
NATM Tunnel Details
• Total tunnel length: 21 km
• NATM tunnel: 4.9 km
• TBM (Tunnel Boring Machine) stretch: 15.5 km
• Side tunnel: 394 m (completed)
Horseshoe-shaped NATM tunnel dimensions: 10.5 m high, 13.6 m wide
Work split in three parts:
• Shilphata stretch – 1.6 km
• First junction point – 1.6 km
• Second junction point – 1.5 km (completed July 2025)
The final breakthrough between Ghansoli and Shilphata is scheduled for September 20, 2025. The tunnel work has faced challenges including hard rock strata, low soil cover, and utility diversions.
Work Status in Maharashtra
• Stations: Thane, Virar, and Boisar station work progressing; first slabs for Virar and Boisar completed
• BKC station: 83% excavation done; base slab casting underway at 100 ft depth at both ends
• Viaducts: Pier foundations ongoing across multiple sites; 48 km of piers cast; full-span box girder launching started in Palghar
• Mountain tunnels: Excavation of 7 tunnels in Palghar; 2.1 km of 6 km heading completed
• Bridges: Construction underway on Vaitarna, Ulhas, and Jagani river bridges
With the NATM breakthrough just days away, the Maharashtra stretch of the bullet train corridor is rapidly approaching completion, marking another major step in India’s high-speed rail journey.