Abstract
To predict the service life of reinforced concrete structures exposed to chloride environment, quantitative measures of ma-terial properties such as the critical chloride content for corrosion of the reinforcing steel in concrete and the diffusion coefficient of the chloride ions of concrete are essential. However, it should be noted that they are influenced by several factors such as concrete mix proportions, cement type, and environmental conditions, etc. Thus, the purpose of this research is to estimate the critical chloride content for corrosion of the reinforcing steel in concrete by the accelerated corrosion tests. For this purpose, cylinder and prism concrete test specimens were made for water-cement (W/C) ratios of 31%, 42%, and 50%, and then the accelerated corrosion tests for them were conducted by electrochemical and cyclic wet and dry salt water method. During the test, corrosion monitoring by half cell potential method was carried out to detect the time to initiation of corrosion for test specimens and its chloride content was evaluated by breaking the concrete test specimens when corrosion of the reinforcing steel in concrete was perceived. It was observed from the test results that the critical chloride content for corrosion of reinforcing steel in concrete would be dependent on both W/C ratio and the type of the accelerated corrosion test, and the critical chloride content of the concrete test specimens used in the study were found to range from 0.91 to 1.63 kg/m3 (0.17~0.31% by weight of cement).