The Mumbai-Ahmedabad Bullet Train project has completed the launching of all 13 heavy portal beams in Ahmedabad, marking a key milestone in the construction of India’s first high-speed rail corridor. The achievement was sealed with the installation of the final and heaviest portal beam at Sabarmati, a critical crossing point on the alignment.
Unlike conventional viaduct spans, portal beams are used where high-speed rail infrastructure has to pass over existing railway lines while maintaining sufficient clearance and ensuring uninterrupted train operations below. In Ahmedabad, these structures are enabling the Bullet Train viaduct to cross some of the busiest sections of the Indian Railways network.
The 18-km Bullet Train viaduct in Ahmedabad crosses the Mumbai-Ahmedabad main line at Maninagar and Vatva, besides the Ahmedabad-Delhi main line at Sabarmati. To facilitate these crossings, engineers designed and launched 13 specialised portal beams—five at Maninagar, seven at Vatva and one at Sabarmati.
Heaviest portal beam installed at Sabarmati
The final beam launched at Sabarmati is the largest and heaviest precast concrete portal beam installed in the Ahmedabad section of the project.
Weighing around 1,640 metric tonnes, the beam measures 34.5 metres in length with a 5.5-metre × 4.5-metre cross-section, making it one of the biggest precast portal beams used anywhere along the corridor. According to project officials, the entire launching operation was completed in about three hours.
The lifting operation was carried out using a 2,200-metric-tonne crawler crane, with the work executed in a confined construction zone under detailed planning and stringent safety measures. The operation was coordinated closely with Indian Railways to ensure that train services on the existing routes continued without disruption during the beam launch.
Specialised structures for complex railway crossings
Portal beams are among the most critical structural components on the Bullet Train corridor because they allow elevated viaducts to cross operational railway lines without interfering with rail traffic below. Their design differs significantly from standard viaduct girders as they must carry heavy loads while spanning wider clearances over multiple tracks.
The Ahmedabad launches included beams weighing between 555 metric tonnes and 1,640 metric tonnes, depending on the location and engineering requirements. While the seven beams at Vatva were comparatively smaller, the larger portal beams at Maninagar and Sabarmati were designed to span wider railway corridors.
Project authorities said the successful completion of all 13 launches demonstrates the advanced construction techniques and engineering capabilities being deployed on India’s first high-speed rail project. With these crossings completed, work on the elevated viaduct can progress further, bringing the Mumbai-Ahmedabad Bullet Train corridor closer to completion.