It’s a Wrap

Fibre reinforced polymers (FRP) are polymeric materials reinforced with continuous fibres having a considerable length-to-thickness ratio. This article describes their use in strengthening the bridge of Calafuria on State Road 1 in the province of Livorno in Italy. This bridge was built in 1947-48, as a 120m long cast-in-situ reinforced concrete structure with an 80m central span, four 9m side spans, and a deck 10m wide. It was soon troublesome, and extensive repairs were made in 1950-56 and 1978-79. It was recently reconsolidated again, after it had continued to show extensive deterioration. It was showing widespread micro and macro cracking, which allowed sulphates and chlorides in the nearby sea water to penetrate its cement mix. Previous consolidation using gunite showed signs of cracking, and the concrete had become carbonated. The bridge's new repair and reinforcement programme had the following stages: (1) removal of the damaged concrete; (2) cleaning of the reinforcement rods with corrosion inhibitor MASTERSEAL 300I; (3) placing extra structural reinforcement; (4) cleaning the concrete; (5) applying the polymermodified mortar EMACO R908; (6) applying the levelling mortar EMACO R909; (7) flexural reinforcement and compression confinement with Mbrace FRP; and (8) application of MASTERSEAL protective coating.