Keywords
corrosion-inhibiting admixtures; mortar;sulfate;resistance
Abstract
Sulfate and chloride-induced corrosion of concrete and steel reinforcement are the most important causes of premature failure of durability of concrete structures. To prevent damage in concrete structures, the application of sulfate-resistant and corrosion-inhibiting admixtures has proven to be an effective method. In this study, a new type of corrosion-inhibiting admixtures including organic and special inorganic components are developed and the properties of mortar mixed with them was investigated. The results show that NC-CZ series of sulfate-resistant and corrosion-inhibiting admixtures have been successfully developed. The mortar with NC-CZ has good resistance to sulfate attack, whose corrosion resistance coefficient of mortar is 1.07, meeting the standard requirement and even larger than that of moderate sulfate-resistant Portland cement. The diffusion coefficient of chloride ion at 28d decreases by 35% around. Meanwhile, the water absorption is obviously decreased. The steel bars in mortar mixed with corrosion-inhibiting admixtures don’t occur rusting. By contrast, the steel bars in mortar without corrosion-inhibiting admixtures occur rusting, whose area rate of corrosion is more than 20%. This study could lead to significant benefits for durability and service life of reinforced concrete structures in China.
Included in
Development and Properties of Sulfate-resistant and Corrosion-inhibiting Admixtures
Sulfate and chloride-induced corrosion of concrete and steel reinforcement are the most important causes of premature failure of durability of concrete structures. To prevent damage in concrete structures, the application of sulfate-resistant and corrosion-inhibiting admixtures has proven to be an effective method. In this study, a new type of corrosion-inhibiting admixtures including organic and special inorganic components are developed and the properties of mortar mixed with them was investigated. The results show that NC-CZ series of sulfate-resistant and corrosion-inhibiting admixtures have been successfully developed. The mortar with NC-CZ has good resistance to sulfate attack, whose corrosion resistance coefficient of mortar is 1.07, meeting the standard requirement and even larger than that of moderate sulfate-resistant Portland cement. The diffusion coefficient of chloride ion at 28d decreases by 35% around. Meanwhile, the water absorption is obviously decreased. The steel bars in mortar mixed with corrosion-inhibiting admixtures don’t occur rusting. By contrast, the steel bars in mortar without corrosion-inhibiting admixtures occur rusting, whose area rate of corrosion is more than 20%. This study could lead to significant benefits for durability and service life of reinforced concrete structures in China.
