Las Llamas Bridge in Santander: Design and Construction of a Concrete Intermediate Arch Bridge

The Las Llamas Bridge is situated in Santander, Spain, and crosses over the Atlantic Park, a landscaped urban park of great interest, giving access to the Santander University from the city. The bridge is designed as an arch with intermediate deck typology. The bridge has a main span of 102 m between abutments. The center of the arch rises 7,8 m high over the deck 60 m in length, continuing beneath the deck with two straight inclined legs connected to the bearings with hinges 81,6 m apart. The inclined legs continue underground until they reach the foundation at the existing rock bed, 9 m below. The bridge has been designed using high strength, self-compacting white concrete C-60. The connection between the arch and the deck is materialized by means of stainless steel rod hangers. The deck is organized in a central box-girder with two lateral cantilevers conceived as inclined precast elements 9 m long, with openings to illuminate the Park's green area under the bridge. Lateral sidewalks are paved with composite wood decking. A central lane passing through the arch end openings holds a path reserved for bicycles.