Method for characterization of the rate of movement of an oxidation front in cementitious materials

摘要

Disclosed are methods for determining the redox condition of cementitious materials. The methods are leaching methods that utilize a redox active transition metal indicator that is present in the cementitious material and exhibits variable solubility depending upon the oxidation state of the indicator. When the leaching process is carried out under anaerobic conditions, the presence or absence of the indicator in the leachate can be utilized to determine the redox condition of and location of the oxidation front in the material that has been subjected to the leaching process.

主权项

1. A method for determining the location of an oxidation front in a cured cementitious material, the method comprising:
obtaining a sample from a cured cementitious material, the sample being obtained at a depth from a surface of the cured cementitious material, the cementitious material including a redox active transition metal indicator that exhibits variable solubility in a solvent depending upon the oxidation state of the redox active transition metal indicator; combining the sample with de-aerated water to form a mixture, the mixture including a liquid portion that includes the de-aerated water and a solid portion; maintaining the mixture under anaerobic conditions for a period of time to form a leachate; examining the leachate following the period of time to determine the presence or quantity of the redox active transition metal indicator in the leachate, the presence or quantity of the redox active transition metal indicator in the leachate being indicative of the redox condition of the sample of the cured cementitious material and the location of the oxidation front in the cured cementitious material.