SU1766887A1 - Raw mixture for foam concrete production - Google Patents

Abstract

The invention relates to building materials and can be used as heat insulation in residential construction, as well as for insulating heat pipes of ductless laying. The composition contains, wt%: cement 45-46; ground quartz sand 45-46, glued colophony 0,19-0,20; sulphite yeast mash 0.0023-0.0068; water the rest. The foam concrete mixture was made by mixing pre-prepared foam with the mineral part of the mortar (cement, ground quartz sand, water). In a dry state, the cement and ground quartz sand were mixed for 1 min (the ratio between the components was 1: 1), after which the mixture was sealed with water, the additive of the DMB was injected with the mixing water, the V / C ratio was 0.7. The average density of the porous mixture was 480-500 kg / m, which ensured the production of foam concrete with a density of 290-300 kg / m3. The strength of foam concrete is 0.8-0.9 MPa. 2 tab. 00 s

Description

The invention relates to building materials and can be used as heat insulation in residential construction, as well as for insulating heat pipes of ductless laying.

Known foam concrete, comprising a tinder, aggregate, foaming agent and additive 1.

The disadvantage of it is low strength

As a prototype of the invention, the composition of foam concrete was adopted, including, m.ch .:

Cement45-46

Ground quartz

sand with specific

surface 4000 cm2 / g35-46

Kepeanifolny

frother 0,19-0,20 2

WaterEverything,

The average density of foam concrete is 290-300 kg / m. Thermal conductivity of 0.070 W / m ° C. The main disadvantage of this composition is the low strength of foam concrete (0.75 MPa).

The aim of the invention is to increase the strength of foam concrete.

This goal is achieved by the fact that the raw mix for the production of foam concrete contains, in May. including:

Cement45-46

Ground quartz

sand45-46

Kleekanifolny

frother0,19-0,20

Sulphate yeast

mash0,0023-0,0068

VI Os O 00 00 XI

Water is the rest.

In foam concrete there is a relationship between the strength of concrete and the quality of its pore structure. The growth of foam concrete strength is due to a change in its pore structure. The addition of SDB affects the pore structure of the material. With the same total porosity, the average pore of foam concrete with an additive of DBB is less than that of a material without an additive, moreover, the pore structure of foam concrete with an additive of CDB is more uniform. All this provides an increase in the strength of the proposed foam concrete by 20%.

The mechanism of action of the SDB on the stabilization of the pore structure of foam concrete can be explained by the fact that, at the phase boundary of surfactants (glue soap that is part of the glue gel coating frother) - cement dough - air creates an additional layer of water molecules that are definitely oriented, which prevents the fusion of bubbles in the foam mass, which contributes to its stabilization and the provision of a high-quality pore structure of foam concrete.

In the production of foam concrete additive, including the RRM, were not used.

In the proposed foam concrete composition, the additive BD does not exhibit plasticizer properties, but uses its property to modify the pore structure: the average pore diameter decreases, the magnitude of variation and the standard deviation, as a result, the pore structure becomes more uniform, which leads to an increase in strength foam concrete.

Example. The foam concrete mixture was made by mixing pre-prepared foam with the mineral part of the mortar (cement, ground quartz sand, water).

The foam was prepared from 300 ml of a gluten-kanifol foaming agent with a density of 1.01 g / cm in a conventional laboratory foam mixer. Duration of beating 6 min. The gluecanniferous foaming agent included the following components, May. h:

Glue mezdrovy3,30-3,40

Rosin pine 1.3-1.4

Sodium caustic

technical0.30-0.31

WaterEverything

In the dry state, cement and ground quartz sand were mixed for 1 min (the ratio between the components was 1: 1), after which

the mixture was shut with water. The addition of the SDB was administered with mixing water. The B / T ratio was 0.7. The average density of the porous mixture was 480-500 kg / m3, which ensured the production of foam concrete with a density of 290-300 kg / m3.

Samples-cubes with a rib of 7 cm were molded in metal molds by injection molding. Pre-autoclave exposure was 12 h. Autoclaving was carried out according to the 4 + 4 + 2 h mode at a vapor pressure in the autoclave of 0.8 MPa (at a temperature of 174.5 ° C).

The obtained samples were subjected to tests for compressive strength (according to GOST 10180-78). The porous structure of the samples was examined by a microscopic method using an MBS-9 microscope.

The compositions of foam concrete and their characteristics are presented in table. 1 and 2.

From the test results (Table 2), it follows that the use of an SDB as an additive increases the strength of foam concrete, improves its pore structure, without having a plasticizing effect. The optimal result can be obtained with the introduction of 0.0023-0.0068 May. h. RRT. With a lower and higher content of the BDI additive, no increase in strength is observed.

Thus, the conducted studies have shown that the use of the BDI additive leads to an increase in the strength of foam concrete by 20%. With an average material density of 300 kg / m3, the compressive strength is 0.9 MPa, which makes it possible to use it in construction as a heat insulating material.

Claims (1)

Invention Formula Raw mix for the production of foam concrete, including cement, ground quartz sand, glue-resin foaming agent and water, so that, in order to increase its strength, it additionally contains a sulphite-yeast cream in the following ratio of components, wt,%: Cement45-46 Ground quartz sand .45-46 Kleekanifolny frother 0,19-0,20; Sulfite Yeast mash 0.0023-0.0068; Water the rest. Table 1 Note: 1 in the numerator, the dosage of NRM is given in% of the total concrete mass, in the denominator - in% of the mass of cement. T a b l and d a 2