Chemical profiles of cement pastes exposed to a chloride solution spray

This paper reports on the findings of a study of the chemistry of chloride penetration into cement pastes. Three binder combinations were used with three types of curing. At certain exposure times, specimens were sliced at 5-mm intervals, ground, and analyzed using X-ray fluorescence (XRF) and thermogravimetry (TG) techniques. Up to 6-month exposure results are reported in this paper. As a result of leaching of calcium, silicon content was used to determine binder content for the XRF measurements. It was found that the vast majority of chloride permeation had occurred by absorption, and that curing by sealing in film or the addition of self-cure admixture more than halved the depth to which chlorides penetrated. In some instances, sodium was present in proportionally higher quantities than chloride, which has been attributed to the replacement of sodium ions by potassium ions.