In the cold snowy region of Japan, the salt (NaCl) is usually used as cheap deicing agent for winter road maintenance. It is observed that these salts not only have harmful environmental influence on living circumstance, but also accelerate the corrosion of steel structure and result in the concrete deterioration, especially under freezing and thawing conditions. The method for improving the resistance of concrete to frost damage under salty condition is hoped. In the present study, the resistance to frost damage of concrete with various mix proportions was investigated under the salty condition. The factors of mix proportion include different water cement ratio from 30% to 90%, different air content from 1.9% to 7.5%, and the use of ground granulated blast-furnace slag (GGBFS) and silica fume (SF) as mineral admixture. The scaling of concrete, the chloride penetration in concrete and mortar, and the pore distribution in mortar were determined. Test results show that the above mentioned factors have remarkable influence on the properties of concrete. The low water cement ratio, the proper air content and the utilization of mineral admixture can improve the resistance to frost damage of concrete even under salty condition.
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