CONCRETE

UDC 666.972.16

Barannikov M. V. Phd tech. sci. candidate, engineer, FGBOU VO \"IGKhTU\", Ivanovo, Russia

Polyakov I. V. chemical engineer, PLASTNEFTEKHIM LLC, Moscow, Russia

Polyakov V. S. Phd tech. sci. candidate., Advisor to the General Director for Science, IVKHIMPROM JSC, Ivanovo, Russia

Alitinform №1 (62) 2021 г. 30-37 p.

Abstract

The influence of complex additives containing organic and inorganic nitrogen-containing substances on the properties of heavy concrete has been investigated. The efficiency of the plasticizing action of these additives at the stage of preparing a concrete mixture and subsequent molding of concrete products has been revealed.
The objects of investigation were samples of concrete grade CEM I 52.5N without additives, as well as modified with ammonium sulfate, carbamide and superplasticizer C-3. Were synthesized water-soluble oligomers of caprolactam, which reduce the dissolution time of the designated nitrogen-containing substances and superplasticizer C-3. This contributes to a better mixing of the components of the concrete mixture, primarily to improve the dispersion of the complex additive in the volume of the concrete mixture. The used oligomer of caprolactam is an effective water-soluble wetting agent for the surface of cement, sand, and crushed stone particles, which is very important for activating hydration and sorption processes during mixing of a concrete mixture.
The obtained complex additives were added to the concrete mixture. The obtained samples – cubes were investigated for compressive strength. It is shown that the additives used have accelerating-plasticizing properties, and also increase the strength of concrete for 28 days by 2–2.2 times.

Key words:

concrete, caprolactam, ammonium sulfate, carbamide, complex additive, compressive strength