SU804604A1 - Concrete mix - Google Patents

Description

(54) CONCRETE MIXTURE

one

The invention relates to compositions of concrete mixtures used to make concrete and reinforced concrete products and structures.

Concrete mixes are known, including cement, crushed stone, sand, thermal power plant ash and water. Ash, as a component of the mixture, is usually used instead of 15-20% of cement, it slows down the process of hardening of concrete, reduces its expansion associated with heat generation in hydrating cement ij.

A significant disadvantage of such mixtures is a decrease in the strength of concrete, since coal ashes are low active and the direct replacement of cement decreases with the direct replacement of cement. Some effect when using these mixtures can be obtained only in cases when high-active cement is used for low-strength concrete or when building massive, for example, hydraulic structures, for which usually low strength is normalized in long-term periods.

The closest in terms of technical effect and effect to be achieved is (token mixture, including weight.h: fixed; 5, K1.) Y11 aggregate 4.5-5.5; sand 2-3,5; ash TPP 0.5-2; surfactant additive 0.0015-0.025 and water 0.75-1 2.

The disadvantages of the known concrete mix are:

1. Restricted application only for cassette products.

2. Set the composition of the mixture only

0 due to the condition of high mobility (cast mixture with a draft of a cone, 20-24 cm), an increase in the quality of the surface and an acceleration of the molding process.

3. Regulated. within narrow limits, cement consumption (160-320 kg / m °), which prevents the production of concretes of grades M-300 and higher.

4. Increased ash consumption (o, 5–2 parts by weight), 0 which improves the mobility of the concrete mix, but does not provide an increase in the density, strength, water resistance of the concrete and a decrease in its water absorption.

five

5. The use of ash with irregular content of unburned carbonaceous residues and with a lower specific surface 1500.

The purpose of the invention is to increase the strength and density of ootone, lower etho-water absorption and water loss. O .MOCTH. The goal is achieved by the fact that a concrete mixture, including wedge cement, coarse aggregate, natural sand, ashes of thermal power stations and water, contains these components in the following ratio in weight. : Clinker cement 1.8-4.4 Coarse aggregate 0.6-1.9 Natural sand Ash teploelektro0, 15-0 stations 0.25-0.7 Ash has a specific surface area from 3000 to 7000, and the number of unburned carbonaceous residues in anthracite ash is not more than 15%, in coal - no more than 5%. The results of the conducted studies show that the improvement in the physicist of the mechanical characteristics of concrete is achieved if the specific surface of the ash is in the range of 3000-7000, and the amount of unburned carbonaceous residue determined by the loss of npjf calcination does not exceed 15% for anthracite ash for coal - not more than 5%. The use of ash that meets the above requirements is effective both in heat and moisture treatment and in the natural hardening of concrete. It has been found that the optimum amount of ash additive is in the range of 100-150 kg / m of concrete. The addition of ash in such amount provides an increase in the strength and density of concrete, a decrease in its water absorption and permeability. The ashes must be replaced not only with a part of the cement, as is usually the case, but at the same time as part of the cement, rubble and sand. At the same time, the ratio between rubble and sand should remain as in a conventional concrete mix without the addition of ash. This in all cases reduces the consumption of cement by 50-70 kg / m as compared with a concrete mix of ordinary concrete.

Portland cement M-500 Amvrosiyevsky cement plant

Table

452

65G1 G

g Obtained and: ГIpe.гI, lg1; th (; m1..h; and concrete has the following xcrc.) with a cement consumption of DX rir .100 to 650 kg per 1 m. Compressive strength, kgf / cm 300-700 0.95-0.98 Density indicator 0.02-0.05 Porosity index -1-5 Water absorption,% D.8-B12 and Water resistance 200-400 Frost resistance of cycles Example. The consumption of components per 1 m of concrete is given in Table. 1. After concrete mixes are prepared, their bulk density and stiffness are determined, then concrete samples are made for testing for strength, density, water absorption and permeability. The test results of the concrete mixture of concrete samples are given in table. 2. The data given in table. 2 show that the concrete according to the invention has a higher kg / c: tween indicators than the prototype: its strength is 1.5-2.5 times higher, the density index increases by 0.06-0.09, water absorption decreases by 2.44 9 times, the waterproofness and frost resistance of concrete increases by 3-5 grades. The concrete mixture according to the invention can be widely used in the mass production of products and structures in order to increase the strength and density of concrete, as well as reduce its water absorption and water permeability. The improvement of the specified physicomechanical characteristics of concrete ensures high durability and durability of the structure under operational conditions. The use of the concrete mixture according to the invention makes it possible to significantly increase the efficiency of using ash as an effective material in the production of concrete and reinforced concrete structures.

Indicators

Volumetric mass .: concrete; mixtures, kg / m

Beiona strength at compression at 28 days after steaming, kgf / cm

Density indicator

Porosity Index

The permeability of concrete, characterized by the filtration coefficient

Brand of concrete for water resistance

Frost wasps tone to; to; rb cycles

Selling tab. one

 T a 6 l and c a 2

prototype

2416 2250

2400

2370

648 256

580

386

-but

-3

, - fO

8.8610

2.1-10

Vyoder lpl

.2.10 13 atm. in tech. 72 hours without a filtrate

AT 2

more

AT 12

B8 B 12

75

400

300 200

Claims (2)

1. Concrete mix, including clinker cement, coarse aggregate, natural sand, ashes of thermal power plants and water, which, in order to improve the strength and density of concrete, to reduce its water absorption and water permeability, it contains the following components at the following correlation , weight, h; one Clinker cement 1.8-4.4 Large aggregate 0.6-1.9 Natural sand Ash teploelektro0, 15-0,48 stations 0,25-0,70 Water 2. Concrete mix according to claim 1, from luchascha p. 1.) ash. power plants have a surface from 3000 to 7000, and the amount of unburned hypharyous residues in anthracite ash is no more than 15%, in coal not more than 5%. Sources of information taken into account in the examination 1. Technical conditions for the use of fly ash from thermal power plants as additives to cement and concrete hydraulic structures and for precast concrete. Gosstroyizdat ML., 1961. 2. USSR author's certificate number 490779, cl. From 04 To 31/10, 1973,