Arrábida Bridge

Arrábida bridge crosses the Douro River, connecting Vila Nova de Gaia to Porto. Built in 1963, the bridge has a total length of 493.20 metres with an arch of 270 metres in chord and 52 metres in height. The continuous deck, spanning the entire 493.2 metres, consists of a girder with 12 beams, measuring 26.50 metres in width and spans of 21.20 metres. In addition to its design and construction process, this exceptional structure set a world record for the span of a concrete arch. In 1998, A2P conducted a detailed inspection of the structure, revealing extensive delamination of concrete and exposed reinforcements due to steel corrosion caused by chloride action penetrating the concrete. It was observed in the deck beams, especially in the area above the arch, at locations of concreting joints or where the concrete was poorly placed and vibrated, resulting in aggregate segregation, and in areas with very small covering. The comprehensive rehabilitation of the bridge included local concrete repairs, crack injection, overall concrete protection through painting, resurfacing and waterproofing of the deck, replacement of expansion joints, and monitoring of the protection status of the reinforced concrete structure.