A Complex Additive for Improving Efficiency of a Gypsum-Cement-Pozzolanic Binder

At present, a lot of hyper-plasticizers and super-plasticizers of various brands are presented at the Russian market of plasticizing additives. But the efficient use of these additives is announced by the producers for compositions on the cement base mainly. This raises the need to study the work of modern plasticizing additives and their complexes in gypsumcement-pozzolanic compositions. The studies conducted make it possible to determine the effect of plasticizing additives and complexes on their basis on the rheological and physicalmechanical properties of a composite gypsum-cement-pozzolanic binder, as well as to determine the optimal content of plasticizers in the composition of the complex additive. It is shown that the introduction of plasticizing additives and their complexes makes it possible to improve the operating properties of products on the basis of gypsum-cement-pozzolanic binders that results in improving the flexural strength by 70.3%, compression strength – by 82.7%, as well as improving the water resistance by 66% at slowing the kinetics of initial structure formation. These results are achieved through the formation of the more dense porous structure of samples on the basis of the gypsum-cement-pozzolanic binder modified with plasticizing additives. Thus, the total volume of pores is reduced by 9%, open capillary pore is reduced by 16.8%, open non-capillary pores is reduced by 1%, the volume of conditionally-closed pores is increasesd by 8.8%, an index of micro-porosity is increased by 0.38. This makes it possible to significantly expand the application field of products on the basis of the modified composite binder when producing a wide range of building products.

V.S. IZOTOV, Doctor of Sciences (Engineering),
R.Kh. MUKHAMETRAKHIMOV, Candidate of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.),
A.R. GALAUTDINOV, Engineer

Kazan State University of Architecture and Engineering (1, Zelenaya Street, Kazan, 420043, Russian Federation)

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