The high-speed railway line “Talayuela-Cáceres” in the section “Alcántara Reservoir – Garrovillas” saves the River Almonte on its arrival at the Alcántara reservoir through a large concrete arch with superior deck of 384 m. main span, with its foundations located outside the reservoir. This large arch span is the main section of a viaduct 996 m. long, and 36 m. tall.
This viaduct will become, in terms of main span, the largest span of high speed rail in the world (surpassing Dashegguan bridge in China, with 336 m.), the largest railway concrete arch (without restricting the high speed) surpassing in over 100 m. the length of the bridge over the lake Froschgrund in the line Nürnberg - Erfurt (270 m.) Germany. Also, it will be the third largest concrete with no distinction of the type of traffic (second only to China Wanxian Bridge (420 m.) and very near the larger of the two bridges between the islands of Sveti Marko and Krk in Croatia (390 m.).
Regarding the relationship arc-deck, spans have been set to 42 m. between the piers in which the deck rests on the arch, which results in a division of 9 span intervals, allowing adequate anti-funicular behavior of the guideline curve axis.
It argues that the separation between the supported piles of the arch and the separation between the piers of approaching spans is similar (42 m. in the first case and 45 m. in the second) and generates an image aesthetically balanced, harmonious and orderly, in order to use a deck with the same section and depth in both areas, facilitating the implementation, erection and subsequent bridge maintenance. Thus, the deck will be a continuous beam of box section and constant depth across the viaduct, executed in situ.
The arch will have an octagonal hollowed section in the central area that will be divided into two hexagonal solid feet in the arising. The bridge will be executed by incremental launch using provisional saying towers, avoiding any needing of piers in the reservoir. The piles which rest on the arch have a beneficial aero-dynamical form, form that will be also present in the rest of the piles for maintaining a visual concordance in the entire bridge.