SU1535858A1 - Gypsum-concrete mix - Google Patents

Abstract

The invention relates to the technology of building materials and can be used in the building materials industry in the manufacture of gypsum blocks, panels, partitions. The purpose of the invention is to increase the frost resistance of gypsum-concrete products. The composition of the gypsum-concrete mixture includes, wt.%: Building gypsum 24.6 - 30.2, carbon ferromanganese slag 40 - 48, sulfamic acid 0.4 - 0.8, water the rest. The compressive strength after drying the samples to constant weight and holding for 60 days in air-dry conditions is 7.2 MPa, the frost resistance is 24 cycles. 5 tab.

Description

The invention relates to the technology of building materials and can be used in the building materials industry in the manufacture of gypsum blocks, panels, partitions.

The purpose of the invention is to increase the frost resistance of gypsum-concrete products.

When carrying out the technical solution, the gypsum-bead mixture is prepared by mixing gypsum, slag, sulfamic acid and water in a screw mixer for 1 minute. Then the mixture is poured into fornas, incubated for 1.5-2 hours, molded and dried at 55-60 ° C until a constant weight is reached. After that, the samples are stored before testing in air-dry conditions with a relative air humidity of 70% for 60 days. As raw materials take gypsum building brands G-6.

Carbonaceous ferromanganese slag is a semi-dry granulation product of the Kosogorsk Metallurgical Plant, consists of glassy and crystalline phases. The amount of the vitreous phase reaches 45%. The crystalline phase is represented by the minerals: gel — 2CaO AljOa-SiO, okermanitom-2CaO-MgO 2Si02, sulphides MnS, MgS, FeS, aldgamite, ft 2CaO SiOj.

The chemical composition of the slag is as follows:

Si02 32.5; AU03 7.91; CaO 38.85; MnO 9.6; MgO 8.35; FeO 0.84; S 1.94.

Slag granulometry is shown below:

Size of sieve, mm Private residues,% 101

52.55

2,525,0

1.2521.05

ate

with

SL

00

ate

00

0.6326.5

0.31518.25

0.145.21

0.090.14

Bulk density pshaka 973 kg / m3. In the composition of the gypsum-concrete mixture, the slag is used as a filler.

Sulfamic acid is a product of Novomoskovsk PO Nitrogen, corresponds to TU V-03-381-80, has the structural formula

H N

N - SO, H

Appearance - crystalline powder from white to gray-white. Incombustible. It dissolves well in water, melts at 205 ° C, molecular weight 97.1.

An increase in frost resistance due to a decrease in the saturation coefficient of the pores of gypsum-concrete products with liquid and gas phases is achieved by using carbon ferromanganese slag as a filler and by addition of Novon sulfamic acid, changing the ratio of these and known components.

Carbon ferromanganese slag is a filler, the chemical composition is similar to calcium compounds and provides the greatest adhesion to a glue (gypsum) with a filler (slag).

Sulfamic acid in the proposed mixture acts as an activator and a blowing agent, which, on the one hand, displaces water from the pores, filling it with gas phase during decomposition, on the other hand, the released and decomposing amine complex makes reactive elements of the group of alkaline earth metals and iron. The introduction of sulfamic acid into the gypsum-concrete mixture composition intensifies the process of gypsum interaction with slag components and promotes the crystallization of aluminum, iron, manganese hydrosulfate compounds and the binding of alkaline-earth metal complexes to practically water-insulin.

The compositions proposed (table. 1) and known (table. 2) gypsum concrete

Q

five

0

five

mixtures and the results of physico-mechanical tests are given in table 1-3.

Based on the data of physicomechanical tests, it can be seen that the proposed composition of the gypsum-concrete mixture is characterized by greater strength and frost resistance than the known one.

Claims (1)

Invention Formula Gypsum concrete mixture, including building gypsum, slag aggregate and water, characterized in that, in order to improve frost resistance, it contains carbon ferromanganese slag as an slag aggregate and additionally sulfamic acid in the following ratio of components, wt.%: Building gypsum 24.6 -30.2 Carbonaceous ferromanganese slag 40-48 Sulfamic acid 0.4-0.8 Water Else Gypsum construction, G-5 Carbonaceous ferromanganese slag Sulfamic acid Water 24.6 27.4 30.2 48.0 44.0 40.0 0.4 0.6 0.8 27.0 28.0 29.0 Table 3