The Mumbai-Ahmedabad bullet train project has completed the installation of all 14 portal beams over the Delhi-Mumbai Rajdhani main line in Vadodara, clearing a major structural hurdle on one of the corridor’s most complex sections.
The 8.3-kilometre stretch passes through densely built areas and crosses five railway lines, including two main lines of Indian Railways. The high-speed rail viaduct also intersects the Rajdhani main line diagonally, requiring specially designed structures to maintain the clearance needed for trains operating below and prevent disruption to the existing railway network.
According to the report, 10 of the portal beams have been installed between Vadodara Bullet Train Station and Vishwamitri Railway Station. The remaining four are located between Vadodara Railway Station and Chhayapuri Railway Station. Together, the structures will support the next stage of work at the crossing of the Rajdhani main line.
Approximately 40-metre-long composite girders will now be placed on the 14 portal beams across the main-line crossing. The viaduct on the remaining portions of the route will be constructed using span-by-span technology, under which successive sections are assembled along the alignment.
The portal beams were built using cast-in-situ construction, meaning the concrete was poured and formed at the project site rather than being produced elsewhere and transported for conventional launching. Each completed beam weighs approximately 1,500 tonnes, according to the report.
The construction method was adopted because the work site is constrained by an active railway network and limited available space. These conditions made the use of a standard precast launching method impractical, particularly over one of the busiest railway routes in the country.
The Vadodara section illustrates the coordination required when a new elevated transport corridor is built through an operational railway environment. Construction teams must work around live tracks, preserve train clearances and complete heavy structural work without interrupting existing rail services. The diagonal crossing of the Rajdhani line added another layer of design and execution complexity.
The completion of the portal beams does not mark the end of construction on the crossing. Composite girders must still be placed over the Rajdhani main line, while span-by-span viaduct construction will continue on the rest of the 8.3-kilometre route. The reported next stage is therefore the installation of the composite girders supported by the completed portal structures.
