Deterioration of reinforced concrete in the marine industrial environment of the Arabian Gulf - a case study

This paper describes the deterioration of reinforced concrete structures at a liquefied gas/sulfur plant that occurred shortly after completion of the construction. Investigations have shown that the principal cause of the deterioration was corrosion of reinforcing steel due to the presence of chlorides, with marine salts being the main source. The primary contributing factor was the increased level of industrial pollutants which, in combination with marine salts, rendered the plant environment highly aggressive to the reinforcement. Other contributing factors included the use of sulfate resisting Portland cement, the presence of hairline cracks in the concrete, the elevated water/cement ratio, and insufficient concrete cover. The problem of corrosion was also aggravated by simultaneous action of multiple environmental factors, such as the high salinity of Gulf water with a consequent high rate fallout of marine salts, high relative humidities and air temperature over much of the year, unfavourable wind speed and direction, intense solar radiation, and corrosive ground conditions. Considering all the data available, it appears that the corrosion process in reinforcing steel at the liquefied gas/sulfur plant is a result of complex synergistic effects of chlorides and acid solutions enhanced by the unfavourable environmental conditions prevailing in the region.