Mumbai-Ahmedabad Bullet Train: First 40m Full-Span PSC Box Girder Launched In Maharashtra

The National High-Speed Rail Corporation Limited (NHSRCL) has launched the first full-span pre-stressed concrete (PSC) box girder of 40 meters in length through the Full Span Launching Gantry (FSLG) at Sakhare Village, Dahanu, Maharashtra, on 6th September 2025.

Scope of the Maharashtra Section

The Maharashtra section of the Bullet Train corridor spans 156 km, including 135 km of elevated alignment from Shilphata to Zaroli village on the Maharashtra-Gujarat border. Of this, 103 km will be constructed using 2,575 full-span girders, each weighing approximately 970 metric tonnes. Other components include 17 km of segmental girders, 2.3 km of steel bridges, 3 stations, 7 mountain tunnels (approx. 6 km), and special earth structures.

Casting Yards and Technology

A total of 13 casting yards are planned along the alignment, with 5 currently operational. This full-span technology has been used in the Bullet Train project since April 2021, helping complete a 319 km viaduct in Gujarat.

Technical Details of the Girders

Each 40-meter PSC Box Girder weighs around 970 metric tonnes and is cast as a single monolithic unit using 390 cubic meters of concrete and 42 metric tonnes of steel. Full-span girders are preferred as they enable construction progress up to 10 times faster than segmental girders.

Specialised Equipment for Launch

The girders are launched using indigenous heavy machinery, including Straddle Carriers, Bridge Launching Gantries, and Girder Transporters. Girders are pre-cast in advance and systematically stacked in dedicated casting yards to ensure uninterrupted supply.