The objectives are(a) modeling of in-core leaching, and (b) experimental testing of the modeling predictions ultimately focusing on application to field-extracted cores. Modeling will formulate chloride transport of chloride in concrete with binding agents, into concrete sampling openings. Variables of special interest include the opening size and geometry, and chloride diffusivity. The model output will be the time evolution of free chloride in suitable collecting medium, with attention to evaluating the terminal amount as function of results acquired in a limited test time. Experiments will use first concrete/mortar laboratory specimens with known amounts of admixed chloride. Openings of various geometries and chloride collecting media will be used to evaluate the time evolution of chloride in the media and contrast the results with model predictions. A preliminary methodology will be elaborated to optimize accuracy based on the modeling and experimental results. Toward the end of the investigation, the preliminary methodology will be applied to samples of concrete extracted from representative field structures, in an attempt to obtain free chloride concentration profiles and derive chloride binding isotherms from the results.
