CORROSION OF REINFORCED-CONCRETE STRUCTURES IN TAIWAN

Corrosion factors were analyzed in four buildings and one bridge located near the coastal areas in Taiwan. It is shown that the contents of Cl- and MgO are higher for seaside structures. The main factor that controlled the corrosion of steel in the reinforced concrete is Cl- penetration, which is much more effective compared with carbonation in marine environment. From the chloride profiles, it can be confirmed that the closer the seashore, the more accurate is the distribution of chloride in the concrete as predicted by diffusion theory and Fick's second law. For 50 years, passive life of steel in seaside reinforced concrete structures, a minimum thickness of 11 cm (4.3 in.) concrete cover is required in Taiwan, Republic of China. Otherwise, a special process on concrete quality control would be needed.