Measurement of Chloride in Concrete by Prompt-Gamma Neutron Activation.

Prompt-gamma activation analysis (PGAA) is an elemental analysis method based on radiative neutron capture that has a high sensitivity to chlorine (Cl). To evaluate the feasibility of replacing the conventional wet chemistry method, ASTM C1152, with PGAA, four mixtures of concrete were prepared with Cl added, ranging from a 0.004 to 0.067% mass fraction of Cl in concrete. The PGAA method detected levels of 100 µg/g Cl in concrete. While both the PGAA and C1152 methods gave results systematically below the nominal values of added Cl, the PGAA data showed excellent correlation (R² of 0.999) with the C1152 results measured on the same samples. Given that PGAA can measure Cl in concrete as well as C1152 and is faster and less labor-intensive, it can be a candidate for development as a standard method for an alternative to the latter. [ABSTRACT FROM AUTHOR]