Project

DETAIL DESIGN FOR THE COMPOSITE VIADUCT AT LEGORRETA. SPAIN

CLIENT ADIF
SERVICE Structural project
DATE 2008
LOCATION Basque Country, Spain
ARCHITECTS EPTISA

This viaduct belongs to the new Basque Country railway network. Section: Legorreta. The viaduct allows for the passage of the high-speed rail line over Zubina river and the road GI-4471, located between K.P. 206+890 and K.P. 207+034. Two prestressed concrete structures form this 144m long box girder bridge, which is divided into three spans of 44m + 56m+ 44m and follows a straight alignment. The total deck width is 14m and it includes a double track line. In order to provide more versatility to the superstructure, the design encompassed two different options to support the railway on the structure: slab track and track on sleepers and ballast. The cross-section is a box girder with an inferior width of 5.50m and an upper width of 6.40m. Lateral cantilevers have a total length of 3.80m, being their depth 0.53m at springings and 0.2m at ends.

The viaduct is a 3.60 m long constant depth structure. A 2% cross slope allowing for water removal starts in the center of the bridge. Pot bearings on piers and abutments support the deck. Piers are made of reinforced concrete with a hollow rectangular section and chamfered corners. A shallow foundation with footing distributes loads. Perpendicular wing walls to retain soil have been added to the reinforced concrete shallow foundation closed abutments.