Study on Influence of High Activity Alkaline Electrolyzed Water on Sulfate Resistance Property of Concrete

Abstract

In this study, a kind of alkaline electrolyzed waters with the pH of 10.5 was used to enhance the sulfate resistance properties of concrete with mineral admixture at different proportioning. The results showed that Alkaline electrolyzed water in concrete can activate the pozzolanic effect of mineral admixtures, leading to an increase of compressive strength. The compressive strengths of electrolyzed water concrete (DJ) were all high than those of natural tap water concrete (TW) at same mineral admixture proportion. Through 120 times of sulfate attack cycles, the sulfate resistance coefficients of TW concrete with different proportions were 90.4~93.7%, and those of DJ concrete is 94.7~96.8%. The sulfate corrosion resistance property of DJ concrete was improved. The corrosion products AFt and gypsum on the surface of concrete were formed by the reaction of Ca2+ in cement paste and free SO4 2- infiltrated into the solution, which would further deepen the internal Ca2+ migration. In order to maintain the overall charge balance, K+ ions in alkaline electrolyzed water moved in, so as to slow down the corrosion of concrete. The SEM micromorphology showed that the internal structure of alkaline electrolyzed water concrete was more dense and compact, the porosity is relatively lower, which was less affected by sulfate corrosion. The microstructure of DJ concrete with mineral admixtures was more developed and denser than TW concrete.