SU893938A1 - Concrete mix - Google Patents

Description

(54) CONCRETE MIXTURE

one

The invention relates to building materials, in particular to the composition of concrete mixtures containing modifying additives.

Known concrete mixture 1, including, wt.%:

Cement23

Placeholder68

Phosphate

sodium0.46

Ammonium iron

sulfate0.20

Water8.34

Closest to the proposed technical essence and the achieved result is a concrete mix 2, comprising, by wt.% .:

Portland cement 10-23

Water3.5-15

Sodium Nitrite .0-0-0,2

Sodium tetraborate 0.03-0.2

PlaceholderEverything

A disadvantage of the known concrete mixtures is the corrosion of the reinforcement during the commissioning of reinforced concrete products in aggressive environments.

The purpose of the invention is the prevention of corrosion of reinforcement during the operation of concrete products in aggressive environments.

This goal is achieved by the fact that the concrete mix for the manufacture of concrete products, including Portland cement, water, sodium nitrite, boron-containing compound and aggregate, contains boric acid as a boron-containing compound in the following ratio of components, in wt.%: Portland 20-25

Water.10-15

Stritis sodium .-. 0.01-0.03

"five

Borna acid 0.02-0.03

PlaceholderEverything

Specific compositions of the proposed concrete mix are given in table. one.

Sodium nitrite and boric acid are introduced.

20 into the concrete mix with mixing water.

In the presence of nitrite, sodium and. boric acid at the pH of the liquid phase 11; 50-8.00 on the surface of the reinforcing steel creates the following: a visually uniform passive film that protects (against corrosion. Reinforcement in concrete samples made from the proposed mixture during storage for 5 months .- in a room containing vapors of the salt salt, did not corrode, remained clean and shiny.

In order to burn the effectiveness of the complex additive (nitrite plus boric acid) on the step of steel reinforcement, the behavior of steel in

Ca (OH) j us. f 1.2 g / l NaNO,

Ca (OH) 2 us. + 1.2 g / l NaNOj + 10 g / l NajB407IO HjO (known)

Ca (OH) 2 us. + 1.2 g / l NaNOj + 2 g / l HjBOa

Sa (OH) us. + 1.2 g / l NaNOj + 3 g / l NZOZ

Sa (OH) us. + 2 g / l NaNOj + 2 g / l NZOZ

a saturated solution of calcium hydroxide with a pH change from a pH of 11.5 to 8.00.

Data on the state of samples, depending on the type and concentration of the additive, are given in Table. 2

The proposed concrete mix can be used for the manufacture of concrete products operating in an atmosphere containing pairs of acids.

Table 1

0,00015

Hard to notice corrosion points (2-3 on the sample)

Also

Clean, shiny, no corrosion points

Also

5 893938

Claims (1)

Invention Formula, Portland 20-g25 Concrete mixture for the manufacture of iron-nitrite and sodium 0.01-0.03 tons of products, including portland cement. Boric acid 0.02-0.03 water, sodium nitrite, boron-containing compound S Substitute The remaining and aggregate, characterized in that in order to prevent the source of information, corrosion of the reinforcement during exploitation, iron-taken into account when examining concrete products in aggressive environments, itI. USSR copyright And 567698, contains as a boron-containing compound | From 04 To 13/22, 1975. nn boric acid prn as follows. 2, USSR author's certificate N 563384, Puny components, wt.%: cl. From 04 To 13/22, 1976. Water 10-15