The influence of wind on chloride accumulation at the concrete surface

Among many different environmental actions causing deterioration of concrete, chlorides are representing one of the most dangerous attacks on the reinforced concrete structure. Numerous chloride analyses were performed on the Krk bridge, which has been exposed to marine environment for more than 30 years. Krk bridge is situated at the Northern part of Adriatic coast, where often very strong winds are blowing which brings sea water to all parts of the structure. Surface chloride concentrations are analysed in relation to the height above sea level and to the orientation of the structural element. In the area of Krk bridge basic value of reference wind speed is 40 m/s, with measured gusts reaching up to 90 m/s. Results show that marine salt deposition at the concrete surface is strongly influenced by wind, its dominant direction and reference wind speed. Based on the analysis of chloride surface concentrations at concrete columns from the Krk bridge, marine chlorides are suggested to be observed as a “loading” in relation to the height above sea level and structural element orientation.