Sulfate-magnesia corrosion of modified concrete

The article discusses the issues of increasing the corrosion resistance of concrete by enhancing the water-reducing effect of plasticizing additives by introducing finely dispersed mineral fillers. The positive effect of fillers on the resistance of concrete samples to aggressive media has been established. The study of corrosion processes was carried out using a complex of various methods. Electron microscopic studies of the corroded surface layers of concrete samples have shown changes in the composition of the cement matrix in depth as a result of the accumulation of magnesium and sulfate compounds. The sequence of the zones of the predominant type of corrosion is revealed, corrosion products of various sizes and morphology are identified. In addition to traditional methods, the pulsed ultrasonic method was used to study the kinetics of corrosion. It is established that the change in the structural and mechanical properties of concrete samples in an aggressive environment affects the speed of passage of the ultrasonic pulse through the sample. The kinetic dependences obtained were used for a comparative analysis of the corrosion resistance of cement materials of various compositions and densities.