Behavior of Reinforced Concrete Subjected to Boric Acid Corrosion of Nuclear Power Plant

Reaches on durability of concrete has been made great advances over the past decades. However, little works have been done on the corrosion of reinforced concrete exposed to boric acid in cooling pond of heating exchange system of nuclear power plant. The purpose of this study is to experimentally investigate the behavior of reinforced concrete in such circumstance. Tests were carried out on specimens cured in a standard moisture room at a temperature of 20±3ºC. Three different concentration of boric solution (2000ppm, 8000ppm, 30000ppm) were simulated to accelerate the corrosion. The compressive and splitting tensile strength,elastic modulus of concrete , mass loss rate of steel bar, bond strength and flexural bearing capacity of reinforced concrete at 60, 90, 120, 150 and 180 days were obtained respectively. The results indicate that the presence of boric acid below 30000ppm does not significantly affect serviceability of concrete. The corrosion is slight for the specimens with crack less than 0.4 mm under flexural loads. Boric acid almost has no effect on the corrosion of the steel bar and bond strength.