These two viaducts, built in 2003, are part of the high speed rail (HSR) line linking Madrid with Barcelona. Both structures cross the wide valley carved by the Anguera River and its floodplain near the town of Montblanc. The overall length of the first viaduct is 924 m and it consists of 28 equal simply supported spans of 33 m. The second viaduct, located 1 km further down, has a total length of 652 m and is composed of 19 spans, of which 16 are simply supported and 3 are part of a continuous girder with a longest span of 42 m.
The deck consists of 14 m wide cast-in-place reinforced concrete slabs on top of two U-shape precast prestressed concrete girders with a depth of 2.45 m. This configuration facilitated the erection of the deck with crawled cranes and accelerated the construction time.
The three-span continuous bridge is made of the same typical U-girders as the rest of the viaduct. The girders become continuous for both permanent and live loads through a connection with prestressing bars. Each span is horizontally fixed in the longitudinal direction at one of its ends with a fixed POT bearing. The piers are very stiff with heights of approximately 10 m and two shafts.
These long viaducts proved that the use of precast elements leads to significant cost savings as a result of the industrialized fabrication and erection methods. A dedicated temporary precast yard was built to fabricate the precast U-girders. The reinforced top slab was cast in place using light moving falsework in five-day construction cycles.
J.A. Sobrino – “Bridges for high speed railways. Chapter 6 Bridges for the high speed railway lines in Spain. Design criteria and case studies”. CRC Press/Balkema, 2009, ISBN: 978-0-415-47147-3, Eds.: Rui Calcada, R. Delgado A. Campos e Matos.