Influence of modifying additives on the structural characteristics and properties of portland cement concretes

The influence of polycarboxylate and naphthalene-sulfone superplasticizers, paraffin hydrophobizator and complex hydrophobic-plasticizing additives on the structural characteristics, physical-mechanical, hydrophysical properties, corrosion resistance and frost resistance of fine-grained Portland cement concretes was studied. Structural parameters of concretes (average and true density; density coefficient; total, open, closed porosity) were compared with compressive strength, water absorption, softening coefficients and salt resistance of materials. It is shown that the introduction of superplasticizers increases the density, softening coefficients and salt resistance, reduces the water absorption of Portland cement structures, and the use of paraffin hydrophobization and complex hydrophobic-plasticizing additives increases the closed porosity as a result of the formation of mosaic hydrophobic films on the surface of solid phases, which have a positive effect on the hydrophysical and physical-mechanical properties of concretes.

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