Abstract
Recently, organic admixtures including fluidizing agent and high-range water-reducing agent are indispensable for high-performance concrete and high strength concrete. However, the influence of organic admixture (superplasticizer) on the process of chloride ion penetration into hardened concrete is not still fully understood. So, the authors experimented on the influence of two kinds of superplasticizer. We found out the influence of naphthalenesulfonic acid-based and polycalboxylic acidbased admixture on the process of chloride ion penetration into hardened mortar by using original rapid chloride permeability tester.
From the result of the above, it is construed that the difference of the major constituent of the superplasticizer will exercise no influence on the penetration of the chloride ion into hardened mortar. However it is explained that the penetration of the chloride ion become smaller in order of the mortar to which polycalboxylic acid-based admixture is added, plain mortar, and mortar to which naphthalenesulfonic acid-based admixture is added. It is also explained that much of the chloride ion is fixed in order of naphthalenesulfonic acid-based admixture, plain, polycalboxylic acid-based admixture, by using EPMA and XRD.
