Structural Flow Model of Plasticized Cement-Mineral Mixtures

The complex type of the flow curve of cement-mineral mixtures plasticized by a polycarboxylate plasticizer is described in this work. The sections on the rheological curve which consistently characterize a pseudoplastic, adilatant or apsevdoplastic (anomalous section), dilatant and pseudoplastic flow type are identified. It is noted that various concepts for explaining the rheological behavior of disperse systems do not allow to analyze the anomalous section. Shear stratification or stalling of the flow explains the presence of such a section. It is established that the cause of the rheological anomaly on the flow curve of the studied plasticized cement mixtures is the formation of structural heterogeneity in a system with a uniform initial distribution of water. The intensity of the rheological anomaly is determined by a change in the structural ratio of the thickness of the interlayer to the diameter of the particle relative to the initial value. A structural model of the process of formation of the heterogeneity of the structure of the studied mixtures is proposed. A geometric criterion that takes into account the structure parameters of the mixture and allows one to establish the boundaries of the flow anomaly is proposed.

A.S. INOZEMTSEV, Candidate of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.),
E.V. KOROLEV, Doctor of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.),
T.Q. DOUNG, graduate student

National Research Moscow State University of Civil Engineering (26, Yaroslavskoe Highway, Moscow, 129337, Russian Federation)

1. Kalashnikov V.I., Tarakanov O.V. On the use of complex additives in new generation concrete. Stroitel’nye Materialy [Construction Materials]. 2017. No. 1–2, pp. 62–67. (In Russian). DOI: https://doi.org/10.31659/0585-430X-2017-745-1-2-62-67
2. Molchanov A.O., Neljubova V.V., Kuz’mina N.O., Strokova V.V. Evaluation of the effectiveness of plasticizers of various origins. Resursojenergojeffektivnye tehnologii v stroitel’nom komplekse regiona. 2016. No. 7, pp. 73–76. (In Russian).
3. Larsen O.A., Djatlov A.K. Improving the efficiency of fine concrete with polycarboxylate plasticizers for monolithic housing construction. Tehnologii betonov. 2013. No. 10 (87), pp. 14–15. (In Russian).
4. Gorbunov S.P., Fedorov Ju.B., Trofimov B.Ja., Gamalij E.A. The effectiveness of plasticizing additives in self-compacting mortar mixtures. Vestnik Juzhno-Ural’skogo gosudarstvennogo universiteta. Serija: Stroitel’stvo i arhitektura. 2005. No. 13 (53), pp. 43–49. (In Russian).
5. Lesovik V.S., Degtev Ju.V., Voronov V.V. Cementing agents for small architectural forms made of self-compacting concrete. Vestnik Belgorodskogo gosudarstvennogo tehnologicheskogo universiteta im. V.G. Shuhova. 2014. No. 5, pp. 85–90. (In Russian).
6. Pustovgar A.P., Buryanov A.F., Vasilik P.G. Features of the use of hyperplasticizers in dry building mixtures. Stroitel’nye materialy [Construction Materials]. 2010. No. 12, pp. 62–65. (In Russian).
7. Petrova T.M., Smirnova O.M., Frolov S.T. Properties of plasticized Portland cement-blast furnace slag compositions taking into account electro-surface phenomena. Vestnik grazhdanskih inzhenerov. 2011. No. 2 (27), pp. 118–123. (In Russian).
8. Plank J., Hirsch C. Impact of zeta potential of early cement hydration phases on superplasticizer adsorption. Cement and Concrete Research. 2007. Vol. 37. Iss. 4, pp. 537–542.
9. Inozemcev A.S., Korolev E.V., Duong T.Q. Rheological features of cement-mineral systems plasticized by polycarboxylate plasticizer. Regional’naja arhitektura i stroitel’stvo. 2019. No. 3 (40), pp. 24–34. (In Russian).
10. Pivinskij Ju.E. Reologija dilatantnyh i tiksotropnyh dispersnyh sistem [Rheology of dilatant and thixotropic disperse systems]. Saint Petersburg: RIO SPbGTI (TU). 2001. 174 p. (In Russian).
11. Kirsanov E.A., Matveenko V.N. Nen’jutonovskoe techenie dispersnyh, polimernyh i zhidkokristallicheskih sistem. Strukturnyj podhod [Non-Newtonian flow of disperse, polymer and liquid crystal systems. Structural approach]. Moscow: Tehnosfera. 2016. 379 p.
12. Ur’ev N.B. Fiziko-khimicheskie osnovy tekhnologii dispersnykh sistem i materialov [Physico-chemical principles of dispersed systems and materials technology]. M.: Himija. 1988. 256 p. (In Russian).
13. Inozemtcev A., Korolev E., Duong T.Q. Study of mineral additives for cement materials for 3D-printing in construction. IOP Conference Series: Materials Science and Engineering. 2018. Vol. 365. 032009.
14. Schatzmann M., Bezzola G.R., Minor H.-E., Windhab E. J., Fischer P. Rheometry for large-particulated fluids: analysis of the ball measuring system and comparison to debris flow rheometry. Rheol Acta. 2009. No. 48, pp. 715–733.
15. Korolev E.V., Bazhenov Ju.M., Al’bakasov A.I. Radiatsionno-zashchitnye i khimicheski stoikie sernye stroitel’nye kompozity [Radiation-protective and chemically resistant sulfur composite building]. Penza, Orenburg: IPK OGU. 2010. 364 p. (In Russian).