Physicochemical fundamentals of modifying concrete mix and concrete

Abstract

It is possible to obtain highly efficient construction conglomerates by modifying the structure of cement stone and concrete. Consequently, modification of the concrete structure in this direction is intended to improve the technological properties of the material. By modifying, it is possible to change the kinetics of the growth of physical properties and the final values of the strength of concrete. Without considering the physical and analytical mechanism for modifying the structure formation of concrete, we note that it is primarily aimed at reducing the amount of water -a mixture in a unit volume of material. However, various studies have proved that in the initial period, the structure formation of the cement stone develops in the optimal direction only at a certain volumetric water content. The limiting reduction in water content makes it difficult to hydrate the binder, limiting the final strength properties of the material. At the same time, the final strength properties of the material are improved with an all-round decrease in the volumetric water content of the mixture. In all cases, the modification of concrete assumes its composition is unchanged from the mixing of the mixture to the final stage of the formation of the concrete structure. At present, only isolated attempts are known to physically modify concrete, for example, during its evacuation. In this case, the optimal amount of mixing water is introduced into the concrete mixture, which ensures the optimal flow of the binder hydration reaction. The subsequent suction of water, changing the initial composition of concrete, leads to a deep modification of its structure formation. In particular, the density of the material and its strength properties sharply increase. It should be noted that physical modification of concrete leads to a change in the nature of fixation of binder particles.