PGAA measurement of chloride diffusion profiles in concrete cylinders

Chloride diffusion is a critical precursor to corrosion of steel reinforcement in concrete structures. The current standard method for estimating chloride diffusion coefficients involves destructive chemical analysis. This work investigates the feasibility of Prompt Gamma Activation Analysis (PGAA) for in-situ determination of chloride distribution in an intact concrete cylinder which has a chloride diffusion depth profile. The profile thus obtained is in good agreement with the result of the chemical analysis of the profile in a duplicate cylinder. This is a first such direct comparison to our knowledge. A diffusion coefficient can be extracted from the profiles for further evaluation.