SU945120A1 - Concrete mix - Google Patents

Description

(5) CONCRETE MIXTURE

FIELD OF THE INVENTION The invention relates to compositions of concrete mixtures containing additives. A known concrete mixture comprising cement, aggregate, water, and a complex additive of potassium carbonate, and borax. Famous concrete mix 1, incl., Mas .: Cement Crushed stone Sand 5-20 Water Carbonate 0.25-, 5 potassium Tetraborate nat0, 05-0.9 ri. The closest in technical essence and the achieved result to the proposed one is a concrete mix, including cement, sand, and a can (in the ratio 1: 2i3.5 at W / C 0.550 and additives from K (5 and 0.75%, respectively). by the weight of cement. Concrete can be used in conditions of negative temperatures G21. The disadvantages of known mixtures and concrete are relatively low workability, strength and frost resistance at negative temperatures down to -15s. The purpose of the invention is to improve the workability of the concrete mix, strength and m resistance of concrete at a negative temperature up to. The goal is achieved by the fact that a concrete mixture, including cement, crushed stone, sand, potassium carbonate, a plasticizing agent and water, will make molasses as a plasticizing agent in the following ratio of components,% by weight: Cement 11-17 Crushed stone 52-60 g Carbonate 1.17-1.67 0.08-0.12 Molasses Else Molasses is a waste of sugar production and is a thick dark liquid (dry matter 80%), soluble in water. The sugar content is 45-50%. The deceleration mechanism caused by sugars is explained by the formation of complexes of various types with calcium, aluminum, and iron. The adsorption of these complexes on the grains of cement and embryos of new hydration phases inhibits both the dissolution of cement grains as compared with the one-component addition of carbonate carbonate and the crystallisation of new growths. Due to this, the hydration and structure formation in the initial period of time slows down, and the mobility of the concrete

Consumption of concrete mix materials

Composition% by weight

Checklist 1 56 20,5

60 21 1.17 0.12

eleven

56 20.5 1,

U

52 20 1.67 0.08 - 9.25

17

56 20.5 1,

Famous

9.5

6.71

8.0

0.1

0,, 46 mixtures are maintained for several hours regardless of the content of tricalcium aluminate in the clinker. Preserving the workability of the concrete mix with the proposed addition for 2-k h ensures the formation of a dense, defect-free structure. Resistance of concrete to the action of alternating temperatures increases. Examples of the composition of the concrete mix are given in table.1. Table 2 shows the effect of antifreeze additives on the workability of the concrete mix (aging in natural conditions). Table 3 shows the effect of antifreeze additives on the strength of concrete (extract, in natural conditions). In tab. The effect of antifreeze additives on the frost resistance of concrete is given. Table 1

ControlOffering8.5

i.5

8.5

Famous

Control80

new 20.96

Proposed

20.2 15,759.9 22.9 87.9

5.3

17.2 9.837, 17.0 64.9

Known 4.5

table 2

6.5

6.53

7.51

Table 3

26.2 100

2it, i493

I

ta) s

O) (U

a ta

Claims (2)

c: I99 "512 Formula of the invention Concrete mix, including cement, crushed stone, sand, potassium carbonate, plasticizing additive and water, -o t-s is characterized by the fact that, in order to increase the workability of the concrete mix, increase the strength and frost resistance of concrete at negative temperatures up to -15 ° C, it contains 10 molasses as a plasticizer in the following ratio, wt .: Cement 11-17 Rubble 52-60 15 10 Sand 20-21 Potassium carbonate 1.17-1.67 Molasses 0, 08-0.12 Water Else Sources of information taken into account during the examination 1. A Tor certificate USSR № 555066, cl. From 04 To 13/22, 1975. 2. Lagoyda A.V. et al. On the temperature limits of the use of concrete with antifreeze additives. - Concrete and reinforced concrete, 19b2, No. 12, p.9-12.