RU2290375C1 - Complex additive for building mix - Google Patents

Abstract

FIELD: manufacture of building materials.

SUBSTANCE: invention relates to composition of powdered complex additive for building mixes, including concretes and mortars used in manufacture of concrete and reinforced-concrete units. Additive comprises of 20-50% Relaksol and additionally 20-40% of industrial-grade lignosulfonates, and superplasticizer S-3 in balancing amount, said Relaksol being a mixture of ballast salts produced in desulfurization process and based on sodium thiosulfate and sodium thiocyanate.

EFFECT: prevented wall saltpetre on part surfaces and reduced atmosphere-caused corrosion resistance at the same strength and frost resistance.

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Description

Technical field

The invention relates to the composition of the powder complex additives for building mixtures, including concrete and mortars used in the production of concrete and reinforced concrete products

State of the art

Known complex additive for concrete and mortar, including superplasticizer - a condensation product of naphthalene sulfonic acid with formaldehyde and lignosulfonates (CA No. 1260963, publ. 09.26.1989)

The closest of the analogues is a complex additive for the building mixture - concrete and mortar, including, wt.%: Superplasticizer S-3 - 5-39; Relaxol is a mixture of ballast salts of coke oven gas desulfurization based on thiosulfate and sodium thiocyanate - 61-95. (RU 2228306, publ. 05/10/2004). Known additive does not have sufficient corrosion resistance in the atmosphere while maintaining strength and frost resistance. In addition, when it is used on the surface of the finished product, a manifestation of salt formation is possible, i.e. output of salt streaks.

Disclosure of invention

The objective of the present invention is to develop and create a comprehensive additive for a building mixture - concrete or mortar, with improved parameters.

As a result of solving this problem, it is possible to obtain technical results consisting in the fact that the formation of salts on the surface of the products is prevented, corrosion resistance in the atmosphere (atmospheric resistance) is increased while maintaining strength and frost resistance.

The indicated technical results are achieved in that the complex additive for the building mixture, including C-3 superplasticizer and Relaxax - a mixture of ballast salts of coke oven gas desulphurization based on thiosulfate and sodium thiocyanate, additionally contains technical lignosulfonates in the following ratio of components, wt.% (On dry matter ):

Relaxaxol 20-50 Technical lignosulfonates 20-40 S-3 rest

The implementation of the invention

The complex additive in accordance with the present invention is prepared by mixing aqueous solutions of C-3, Relaxax and technical lignosulfonates. The prepared mixture of solutions is fed into the dryer, where it is dried at a temperature of 120-150 ° C. Drying is carried out until a finished additive is obtained in the form of a powder or microgranules.

The resulting additive in the form of a pre-prepared aqueous solution of the working concentration (optimal concentration of the solution is 32-37%) or in the form of a powder or microgranules is introduced into the mortar directly into the concrete mixer with the first portions of mixing water.

The amount of this additive is 0.6-1.0% by weight of cement, calculated on the dry matter.

An example embodiment of the invention:

The properties of the claimed complex additives are investigated in the composition of the concrete mixture.

The consumption of components of the concrete mixture, kg / m ³ concrete, is:

Portland cement of the PTs400D20 brand in accordance with GOST 10178 530 Sand quartz with a particle size 2.5 according to GOST 26663 760 Crushed stone of fraction 5-20 mm in accordance with GOST 25820 1100 Drinking water in accordance with GOST 23732 208

The plasticizer C-3 used is produced in accordance with TU 5870-002-58042865-03 with rev. one.

The additive is introduced with mixing water in an amount of 0.6% by weight of Portland cement per dry substance.

The compressive strength of concrete is determined according to GOST 18105-86.

Corrosion resistance in the atmosphere (atmospheric resistance) of concrete is judged by its strength and appearance. The atmospheric resistance was determined experimentally by changing the strength of concrete with the additives used after alternating wetting (cycles) for 6 hours each and drying at 105-110 ° C.

The compositions of the complex additives and the properties of concrete with the specified additive are shown in tables 1 and 2.

Table number 1 No.
p / p The content of components, wt.% S-3 Technical lignosulfonates Relaxaxol one 40 twenty 40 2 twenty thirty fifty 3 10 40 fifty Table number 2 No. Composition Compressive Strength (28 days), MPa Frost resistance cycles Weather resistant. Strength change, MPa, cycles High education Before the test fifty one hundred one 38 one hundred 38 40 41 No efflorescence 2 40 150 40 44 44 No efflorescence 3 5 150 45 45.5 47 No efflorescence

As follows from the test results shown in table 2, concrete using the additives of the present invention has corrosion resistance in the atmosphere and there is no salt formation on the surface of the concrete.

Claims (1)

A comprehensive additive for a building mixture, including С-3 superplasticizer, Relaxol - a mixture of ballast salts of coke oven gas desulfurization based on thiosulfate and sodium thiocyanate, characterized in that it additionally contains technical lignosulfonates in the following ratio, wt.%: Relaxaxol 20-50 Technical lignosulfonates 20-40 S-3 Rest