| "It is well known that the properties of chloride ion penetration through concrete are one of the most important factors to evaluate the durability against chloride induced corrosion of reinforced concrete structures. Accelerated chloride ion penetration tests have been expected as the useful method which can rapidly assess the chloride diffusivity of concrete. Nowadays, most of accelerated tests for evaluating the chloride diffusivity of concrete are based on the non-steady state chloride ion migration in electric field, or based on the chloride diffusion under the condition of high chloride ion concentration in solution. In Japan, JSCE has established the method for the steady state chloride ion migration test in electric field as JSCE G 571, and the high concentrate chloride ion diffusion test as JSCE G 572. In addition, the Nordtest method, NT BUILD 492, which is based on the depth of AgNO3 colored part after suit charging, has been thought as the useful method for assessing the chloride penetration through concrete. However, the detailed profiles of chloride ion after applying these methods are still remained as the unknown matters. Moreover, the influences of the measurement methods, such as AgNO3 spraying method, grinding method and EPMA mapping method, on the result of chloride profiles are also not clear. Therefore, in this study, as for the Nordtest method and chloride penetration test under charging condition, the relation between experimental conditions and results was discussed with the comparison of the non-steady state chloride ion concentration profile by the method of AgNO3 spraying, the grinding and the EPMA." |
