• Location: Cantabrian Motorway (A-8), Tamón – Villalegre Section (Asturias, Spain) SEE MAP
• Scope of Works: Detailed Design and technical assistance for the construction of Alvares viaduct
• Client: Ministry of Public Works (Spain)
• Date of project: 1998
• Opening date: 2005
• Main features: Detailed Design of 14 structures, including 3 viaducts
• Length of the section: 8,8 km

In the project “New road; A-8 Motorway, N-632 from Ribadesella to Luarca. Section: Tamón-Villalegre” TORROJA INGENIERIA did the Detailed Design of the structures of that section: viaducts, structures that cross the motorway, intersection structures or motorway accesses.

Specifically, the following structures were designed:

3 Viaducts: Molleda, Corvera and Alvarés (only the Alvarés viaduct was finally built according the original TORROJA INGENIERÍA solution)

5 Overpasses for roads or at intersections

6 Underpasses for roads or at intersections

The Alvares Viaduct is especially remarkable because of its technical complexity. During the construction TORROJA INGENIERÍA also provided the technical assistance needed. The structures is a continuous bridge 383,3 m long with spans 2×49+102,08+3×49+36,75 m long. There is only one deck for both carriageways so it is 27 m wide. The deck is a composite steel-concrete structure with a steel box 8,5 m wide and 4,485 m deep, and a top cast on-site concrete slab over it. There are transverse cross truss diaphragms and inclined struts, both made of steel. Two parts of the deck were built behind the abutments and then they were launched from each side to reach the centre of the main span.