NHSRCL adopting Full Span Launching Method for MAHSR viaduct

New Delhi: To expedite the construction of the MAHSR viaduct, National High-Speed Rail Corporation Limited is adopting Full Span Launching Method (FSLM). The Full span grinder launching equipment for the launching of Full Span Pre-Stressed Box Girder (40 m) weighing 970 MT, Four heavy equipment are used:

1 – Straddle Carrier; 2- Bridge Gantry; 3-Girder Transporter; 4-Launching Gantry

1. A straddle carrier is used to handle the Full Span Precast Box Girders. After casting, Straddle Carrier lifts the girder from the casting bed and transports it to the stacking yard. Further, it feeds the girder from the stacking yard to Bridge Gantry for an erection over Piers. 

This is a tyre-mounted self-propelled equipment weighing approx. 620 MT having a lifting capacity of 1100MT. 

Bridge Gantry

2. Bridge Gantry is a type of crane, which is deployed in a set of two weighing 425 MT each, for lifting of full span box girder from ground till Pier top. It also feeds the girder to the Girder Transporter for subsequent launching of girders using Launching Gantry.

Girder Transporter

3. Girder Transporter is a 27 axle tyre-mounted (i.e.216 numbers of wheels) self-propelled trolley with carrying capacity of 1100MT. Girder transporter weighs approx. 390MT.  Girder transporter is used to transport precast girders (40 m span) over the already erected girders and it feeds the girders to the Launching gantry for erection over the Piers. 

Launching Gantry

4. Launching Gantry is used to lift the precast girders from the girder transporter & place them at a predefined position over the Piers. Launching Gantry then moves forwards to repeat the sequence for subsequent full span girder erection. Launching Gantry weighs approx. 540 MT and handling capacity of 1100 MT.