Concrete structure with complex additives

The article presents the results of a study of the structure of concrete with complex chemical additives, which are used for water-resistance of concrete. Studies have shown that an increase in the physical and mechanical properties of concrete, including water resistance and frost resistance, is achieved by controlling the process of structure formation both at the design stages of the composition and preparation of the concrete mixture and at all stages of product manufacturing. The objective of this research is to study the structural indicators (Wo, λ, α) of concrete with increased water resistance, depending on the cement consumption with an increase in cement consumption from 350 kg/m3 to 450 kg/m3 in concretes with a complex additive C-3 + KE 119-215 and without chemical additives, a decrease in the kinetics of water absorption is observed. The results of the study showed that concrete with complex chemical additives has uniformly distributed small closed pores, while the average pore size and water absorption decrease. The introduction of the KTP additive into the composition of the cement stone promotes air entrainment, as evidenced by the pores in the photo. No neoplasms are observed in the pores, crystals of Ca(OH) on calcium hydrosulfoaluminate (ettringite) are visible. The study of the cement stone with the addition of C-3 showed that the formation of calcium carbonate CaCO3 is observed, and in the samples with additives, KTP -the formation of calcium carbonate CaCO3 of the hydrosulfoferrite C3FGH32 (analogous to ettringite).