IMPROVEMENT OF CEMENT CONCRETE EFFICIENCY DUE TO APPLICATION OF COMPOSITE BINDER WITH SILICATE-CALCIUM DISPERSION
UDK 691.542; 691.32
Shoshin, E. A. Candidate of Technical Science, associate professor, Department \"Building materials and technology\", Yuri Gagarin State Technical University of Saratov, Russia
Strokova, V. V. V.G. Dr.-Ing, professor, Department of \"Materials and Materials Technology\", Shukhov Belgorod State Technological University, Belgorod, Russia
Kozlov N. A. Candidate of Technical Sciences, Associate Professor of the Department “Construction Materials and Technologies”, Saratov State Technical University named after Yu. A. Gagarin, Saratov, Russia
Gribkov D. S. graduate student, Saratov State Technical University named after Yu. A. Gagarin, Saratov, Russia
Alitinform №4 (57) 2019 г. 22-29 p.
The paper is devoted to the study of the potential use of calcium silicate dispersion (CSD) as part of ordinary heavy cement concrete as a replacing cement component. The physical characteristics of CSD (porosity, particle morphology, granulometry, specific surface) are considered. Significant differences in the specific surface area by Blane Machine and BET-method are due to the morphology of xerogel particles in the composition of CSD. Xerogel represent itself aggregated particles with a developed surface and nanoscale porosity that determines its high water-holding ability and the effect on the structure formation of the cement system. The elementary particles of the xerogel are amorphous calcium hydrosilicates, which act as nucleation centers of the C-S-H phases of the cement stone that lead to compaction of the stone structure. The influence of CSD on the properties of cement concrete of grade B25 as an additive to a binder and a component of a composite (cement–CSD) binder is considered. The addition of CSD in the amount of up to 30 % provides an increase of concrete strength by 34.8 % and access to the waterproof and frost resistance grades of F300 and W12, respectively. When replacing 50 % of cement in composite binder with CSD an increase in compressive strength by 13 % is achieved. The high specific surface area of CSD, as well as the presence of extractable carbohydrate in its composition, determines the extreme nature of changes in the setting time of concrete mixtures.
synthetic calcium silicates, xerogel, morphology, granulometry, porometry, cement, concrete, setting time, compressive strength