CARBONATION TESTING
Carbonation is one of the two main causes of corrosion of steel in concrete.
Carbonation testing consists of a coloured dye that is sprayed on the surface of the concrete. The solution will change to pink in un-carbonated concrete and will remain colourless when sprayed on carbonated (low pH) concrete.
By spraying the solution along a core drilled from the top surface down to the reinforcement bar, it can be readily seen how far the carbonation has progressed.
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The sample to the right shows the carbonation has reached the top of the rebar.