SU1203069A1 - Building raw mixture - Google Patents

Description

one

 The invention relates to building mixtures used in the manufacture of building materials and products, such as artificial stones or slabs with thermal insulation properties, and can be used in the construction of various types of buildings in rural areas.

The purpose of the invention is to reduce the stiffness of the molding material prepared from the mixture, as well as improving the fire resistance of products

Raw construction mix contains, wt.%: Portland cement 30-40; natural quartz sand 32-40; chopped wood waste 5.5-7.5; wood flour 0.03-0.3; phosphate disubstituted ammonium 0.02-0.2; sodium tetraborate 0.03-0.3; water the rest

Wood flour in the mixture prevents the aggregation of Portland cement particles during the preparation of the molding mixture from the mixture, and also contributes to an increase in the uniform distribution of Portland cement in the volume of the mass. An aqueous solution of phosphate of disubstituted ammonium and tetraborate of sodium has a fibrillation effect on the fibrous structure of wood flour particles, i.e., in this solution, the wood flour fibers are split on their constituents fibrils, resulting in capillary particles in the wood flour. a structure that provides free access of water to Portland cement particles in the process of its hydration. With this, the process of hydration of Portland cement particles in the volume of products molded from the mixture proceeds evenly and simultaneously, which ultimately contributes to a more complete realization of the strength properties of Portland cement. The use of wood flour in an amount of less than 0.03 wt.% Is not a sufficient obstacle to the aggregation of Portland cement particles in the preparation process from the molding sand mixture and does not create significant capillarity sufficient to ensure free access of water to Portland cement particles when its hydration. The use of wood flour in an amount of more than 0.3 wt.% Reduces the strength characteristics obtained from the proposed

ten

15

20

030692

product mixtures due to significant dilution of Portland cement with wood flour, which reduces the activity of the setting of Portland cement particles during the hardening process of the molded products, and also reduces the fire resistance of the latter,

In the proposed mixture using a fraction of wood waste 0.5-10 mm (both sawdust and shavings). obtained by sieving through a sieve and representing a passage through sieves with a hole diameter of 10 mm and the residue on the screens with a hole diameter of Oj5 mm, i.e. said wood waste is a mixture in which the minimum particle size is 0.5 mm and the maximum 10 mm. For large inclusions in wood waste in the material made from a mixture of products, there are in the appropriate places sinks, voids, local cracks, etc., which leads to a decrease in the physicomechanical parameters, in particular strength characteristics. The presence of particles with a size of less than 0.5 mm reduces the mixing speed of dry components (a mixture of wood flour and portland cement with wood waste} and does not achieve a high homogeneity of the preparations from the mixture of the molding mixture. In order to achieve a high homogeneity of the molding composition, discrete particle sizes are necessary.

The maximum particle size of the wood flour used in the proposed mixture is 0.2 mm. As wood flour, finely dispersed waste formed during the polishing of wood products is used, or the passage of wood waste through sieves with a hole diameter of 0.2 mm, i.e. wood flour used in the proposed raw mix is a mixture of wood particles having a size of 0.2 mm or less.

25

thirty

35

40

45

In the proposed raw mix, air-dried wood waste and wood flour with a moisture content of not more than 5% are used. At higher humidity, wood waste and wood flour are lumpy, especially wood flour, which makes it difficult to mix the components during the preparation of the mixture and not allows to achieve uniform distribution of wood flour particles

between particles of Portland cement in the process of mixing and that, in turn, leads to a decrease in the strength characteristics of the products manufactured from the mixture or to a significant waste of Portland cement. In the case of uneven distribution of wood flour particles between the particles of Portland cement, aggregation of Portland cement particles occurs. Therefore, in the process of hydration, Portland cement blocks itself; water does not sufficiently penetrate into the depth of these aggregated particles, as a result of which the products do not have sufficiently high strength properties.

The combined use of phosphate of disubstituted ammonium and tetraborate of sodium in the raw mixture imparts flame-retardant properties to the product made from the mixture. Their aqueous solution, as noted above, has a fibrillating effect on the fibrous structure of wood flour particles and, in addition, has surface-active properties that significantly reduce the stiffness of the prepared mixture of the molding mixture, which improves its workability, resulting in a drastically reduced time necessary for vibro compaction of molded products, which leads to energy savings and improved working conditions. Quantitative ratios of disubstituted ammonium phosphate and sodium tetraborate are determined experimentally. The use in the raw mixture of phosphate dibasic ammonium and tetraborate sodium in amounts of less than 0.02 and 0.03% bo, respectively, does not lead to a significant decrease in the rigidity of the molding material prepared from the mixture and does not provide sufficiently high flame retardant properties of the products made from the mixture, and the use of phosphoric acid disubstituted ammonium and tetraborate sodium in quantities of, respectively, greater than 0.2 and 0.3 wt.% is impractical because it does not lead to further increase in any physicomechanical properties of the raw mix and products made from it, but only leads to higher prices for the latter.

203069

The total amount of Portland cement, natural quartz sand, phosphate disubstituted ammonium,

5 tetraborate sodium and wood flour creates a sufficient curvature of the surface of shredded wood waste with the specified optimal particle sizes of the latter and,

10 thereby ensures that the material of the products made from the mixture is flammable.

Raw construction mixture is prepared as follows.

15 Example. For preparing each 100 kg of raw mix, 30 kg of portland cement M-400 is taken, i.e. its calculated amount, and mixed with a calculated amount of wood flour of 0.03 kg. The mixing time is 1 minute. Then to the resulting mixture with continued. natural quartz sand 40 kg and woody

25 sawdust with a particle size of 0.5-10.0 mm 5.5 kg and continue to mix for another 2 minutes, after which water is poured into the prepared mixture with continued mixing.

30 closure of 24.42 kg with previously dissolved in it calculated amounts of phosphate disubstituted ammonium and sodium sulphate, respectively, 0.02 and

-, 0.03 kg and mix for 3 minutes. All operations for the preparation of the proposed mixture are carried out in a forced mixer. Cooked like this

In the manner of the molding material, products are molded by vibropressing in the matrix of the vibropress. The duration of vibropressing is 30 s, the oscillation frequency is 50 Hz, the amplitude is mm. Hardening products and drying is carried out in

at room

45

natural temperature conditions (18-25 C) ..

Examples 2-9. The process is carried out analogously to example 1 with the difference that they take qualitative and quantitative composition of the components according to examples 2-9.

Table 1 shows examples of a specific version of the compositions of the prolonged raw material building mixture, test examples, proving the materiality of those entering the project, i, 4.M .ii

J 2030696

a mixture of traits and their synergism (strains of the molding m; sss and izgochnyy 3 (ixi) eKT from the totality of the nazi samples used for H j j her, and, also a well-known example, the basis of the compositions given in

in tab. 2 - physical and mechanical

tab.

Portland cement M-40030,0

Sawdust with size

5.5

particles of 0.5-10.0 mm

Wood chips with a particle size of 0.5-10.0

Natural quartz sand 40.0 Wood flour0.03

Phosphate of disubstituted ammonium 0.02

Sodium tetraborate 0.03 Voda2A, A2

Sawdust with a particle size of 0.5-10.0 mm, mineralized with 0.5% calcium chloride solution

Polyvinyl acetate emulsion AO, O 35.0 37.6 37.6 37.6 37.6 37.6 33.3 36.6

6.4 6.4 6.46.46.4

7.5 6.0 -,

32.0 35.0 38., 6 38,638,638.6 33.3 36.6

0.3 0.2 0.1 --0.10.1

0.2 0.1 0.05 -0.05-0.05

0.3 0.05 0.09 -0.080.08-

19.7 -23.55 17.7 17.4 17.2717,2217.25 24.4 17.0

   5 4, -9

  ..S, 4.9

1665 1690 1680 I 720

snoG (based on

tab.

Table I

T v b l i c a 2

0.34 0.37 0.36 0.38

Editor N. Gunko

Order 8382/29 Circulation 604 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab ,, d.4 / 5

Branch PPP Patent, Uzhgorod, st. Project, 4

Continuation of table 2

Compiled by N. Shchekin

Tehread 3, Pali Proofreader S. Vekmar

Claims (1)

1. RAW MATERIAL MIXTURE, including Portland cement, natural 'quartz sand, crushed wood waste and water, characterized in that, in order to reduce the stiffness of the molding mixture prepared from the mixture, as well as to increase the fire resistance of the products, it additionally contains wood flour, phosphate disubstituted ammonium and sodium tetraborate in the following ratio, wt.%: Portland cement 30-40 Natural quartz sand 32-40 Shredded woody waste 5.5-7.5 Woody flour 0.03-0.3 Phosphoric acid double disubstituted ammonium 0.02-0.2 Tetraborate sodium 0.03-0.3 Water Rest 2. The mixture according to claim 1, I distinguish “In addition, it contains sawdust or shavings with a particle size of 0.5-10 mm as ground wood waste.