Concrete Mix Structure and Role of Water in Its Physical-Chemical Transformation in Concrete

Number of journal: №4-2018
Autors:

Vernigorova V.N.
Sadenko S.M.

DOI: https://doi.org/10.31659/0585-430X-2018-758-4-52-55
УДК: 666.965.022.7

AbstractAbout AuthorsReferences
The concrete mix structure is considered: the subsystem СаО–SiO2–Н2O, basic and acid adsorption centers by Lewis, interaction of water molecules with them with proton transfer, hydrolysis of non-stoichiometric, unstable silicate minerals and formation of the nano-structure in the concrete mix, consisting of their nano-gels SiO2, Са(ОН)2, interaction of the nanostructure with water with formation of intermediate active particles Н+, ОН–, Н*, ОН* leading to the setting. Intermediate active particles interact with adsorption centers and between themselves. Recombination of water molecules takes place but by the law of preservation, charges on the surface of nano-particles are retained, as a result of which the setting occurs. Oversaturated unstable solid solutions (calcium hydrosilicates) are formed, they are subjected to the spinodal decomposition with the formation of nano-clasters of hydrosilicates very active at the moment of release which leads to hardening. It is shown that setting and hardening is the dimensional and chemical effect of nano-particles, calcium hydrosilicates and other particles leading to setting and hardening. The main and initial condition for realizing these processes is an irreversible exothermic reaction of water decomposition into radicals Н*, ОН*with compensation equal to 25 kJ/mol.
V.N. VERNIGOROVA, Doctor of Sciences (Chemistry),
S.M. SADENKO, Candidate of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.) Penza State University of Architecture and Civil Engineering (28, Germana Titova Street, Penza, 440028, Russian Federation)
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For citation: Vernigorova V.N., Sadenko S.M. Concrete mix structure and role of water in its physical-chemical transformation in concrete. Stroitel’nye Materialy [Construction Materials]. 2018. No. 4, pp. 52–55. DOI: https://doi.org/10.31659/0585-430X-2018-758-4-52-55 (In Russian).


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