SU1070131A1 - Concrete mix - Google Patents

Abstract

CONCRETE MIXTURE, including granulated phosphorus slag, crushed stone, sand and a curing activator, characterized in that, in order to increase the water resistance of concrete, it contains as a activator of hardening magnesium nitrate and calcium nitrite in a mass ratio of 2.1-2.2 at follow dem otnoshe-, scientific research institute of components, wt.%: The granulated phosphoric slag 15-25 Sand 11-20 Magnesium nitrate and calcium nitrite 1-2 Crushed stone. The rest

Description

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The invention relates to construction materials and can be used in industrial and civil construction, as well as for the manufacture of hydraulic products such as chutes, pressure pipes.

Known concrete mixture tlj, containing, in May.%:

Granulated blast-furnace slag 21 Sand23

Crushed stone54

Salt activator () 2 The disadvantage of this concrete mix is the low grade of concrete obtained from it.

Closest to the proposed is concrete mixture C23, containing | wt.%:

Ground granulated phosphoric slag25-30 Rubble50-52 Sand18-22 Activator

hardening 1.0-2.0

A disadvantage of the known concrete mix is the relatively low water resistance.

The purpose of the invention is to increase the water tightness of concrete.

The goal is achieved by the fact that the concrete mixture, including granulated phosphorus slag, crushed stone, sand and curing activator, contains magnesium nitrate and calcium nitrite in a mass ratio of 2.12, 2 as a curing activator, in the following ratio of components, wt.%:

Granulated

Phosphoric slag 15-25

Sand 11-20

Magnesium nitrate and

calcium nitrite 1-2

Crushed

The raw materials used are granulated phosphorus slag, ground to a specific surface of 3000-3500 and having the following chemical composition, in May.%: CaO 41.4-48.3; SiO 41.0-44.0, l1 „0, 5.5-7.3; MgO 2.5-3.2; P20j 0.25-1.6, 0.5 / - the rest, as well as rubble from granite rock with a bulk weight of 1324 kg / m, a density of 2330 kg / m and a particle size of 5-20 mm, feldspath sand with a density of 2670 kg / m and a particle size of 2.22.4, and a complex activator of hardening consisting of magnesium nitrate and calcium nitrite . .

Samples — cubes of size cm — were prepared from the resulting concrete mix with a water ratio of 0.30–0.32 to determine their strength and samples — cylinders 15–15 cm in size — to determine their watertightness, compacted on a vibrating plate and subjected to steaming mode 2 + 10 + 2 h at 95 ° C.

The estimated amount of the complex activator is mixed with the mixing water.

Testing of samples for water-tightness. The bridge is conducted according to GOST 12730.5-78, and for strength - according to GOST 10180-78. Concrete grade 300, 400, 500 and 600 with enhanced water resistance is prepared,

In that, bl.1 presents the proposed-. wash concrete mixes; in tab. 2 - their physico-mechanical characteristics in comparison with the known composition.

Table 1

600

Famous

Proposed

300 1

B4-B5

35

AT 6

400 500 600

The hydrate phases of concrete are represented by tobermorite gel and CSH. Moreover, the activators do not remain in the free mode; state, and are included in the structure of calcium hydrosilicates, which has a beneficial effect on improving the water resistance of concrete.

Continued table. 2

44 56 64-69

B7 B8-B9 EY or more

As seen from Table 2, the water resistance of the samples increases in rto comparison with the prototype.

The economic effect in comparison with concrete based on slag cement is 314 thousand rubles. on 100 thousand m.

Claims (1)

CONCRETE MIXTURE, including granular phosphoric slag, crushed stone, sand and a hardening activator, characterized in that, in order to increase the water resistance of concrete, it contains magnesium nitrate and calcium nitrite in a mass ratio of 2.1-2.2 in the following ratio ratio of components, weight. Granular Phosphorus Slag Sand Magnesium Nitrate and Calcium Nitrite 15-25 11-20 1-2 Else § (/) C '>