The paper studies the influence of aggregates and fillers with negative and positive electrical surface properties on the corrosion resistance of concrete. The advantage of resistance of fine-grained concrete on marble sand in comparison with concrete on quartz sand, regardless of the type of aggressive environment, is established. At the same time, the stability of samples of powdered concrete with 10 and 30% of fine-grained filler changed little when replacing the quartz powder with marble one. It is shown that the resistance coefficients of powdered concrete samples with quartz filler (10%) do not differ from the resistance coefficients of samples of a similar composition with crushed marble filler, and with an increase in the dosage of the filler (30 %) slightly exceed. It was found that in powder concretes without aggregates, the contact layer between the cement matrix and the aggregate is absent, so the composition of the mineral powder plays a much smaller role in the corrosion processes of cement stone. The obtained results allowed establishing that electrokinetic phenomena play a secondary role, and the main influence on the stability of fine-grained concrete is the processes of pore colmation by chemical reactions, as well as the interaction of the surface layers of the aggregate with the cement matrix.

It is widely known that modern anionic surfactants are adsorbed at positively charged active centers of hydrate phases in portland cement that leads to floccules decomposition as well as a release of immobilized water, therefore increasing cement paste flowability. Normally, in cement based concrete such fine and coarse aggregates as quartz sand, granite, sandstone etc. are used. They contain negatively charged active centers, therefore, are inert to anionic water-reducing admixture and don’t affect fluidization of cement based concrete mixture. For instance, quartz sand with high concentration of fine particles as well as oxides and hydroxides of Al and Fe cations demonstrates a higher reactivity to anionic water-reducing admixtures. In order to increase the efficiency of anionic surfactants in concrete mixtures the treatment of aggregates with salts based on two-and three-valent cations was proposed. That provides a higher concentration of positively charged active centers on quartz sand surface leading to increase of flowability of concrete mixture.

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