Outline of the Standard NDIS 3437: Test Method for Penetration Depth of Chloride Ions into Hardened Concrete by Spraying AgNO3 Solution
By Y. Aoki, T. Sawamoto, K. Morihama and K. Kawamata
Concrete Journal, Vol.60, No.3, Mar. 2022
- Synopsis
- When a silver nitrate (AgNO3) solution is sprayed on a section of concrete in which chloride ions have penetrated from the outside, the areas containing more than a certain amount of chloride ions turn white, while the other areas turn brown. Based on this phenomenon, a test method to quickly visually check the penetration depth of chloride ions was established as the NDIS 3437 standard by the Japanese Society for Non-Destructive Inspection. This report introduces the background of the creation of this standard, an outline of the test method, the principle of the AgNO3 solution spraying method, and the points to be noted regarding its implementation.
- Keywords:
- Chloride attack, Chloride ion, Chloride ion penetration depth, AgNO3 solution, Spray
