SU1331852A1 - Concrete mix - Google Patents

Abstract

The invention relates to the building materials industry and can be used in the manufacture of structures made of concrete and reinforced concrete on slag base in the holding. The aim of the invention is to increase the crack resistance. Concrete mix contains, may. %: finely dispersed blast furnace granushak 8–20, an aqueous solution of an alkaline melt with a p of 1.25 g / cm 5.2–10, fine aggregate from the group of expanded clay, agloporite, coal waste or ash and slag fuel burned 1-3 and large aggregate of dense rocks the rest. The concrete mix provides a coefficient of crack resistance of 1.09-1.41, strength 26.3-64.3 MPa. 7 tab. S (L oo with CX) joint venture to

Description

The invention relates to the building materials industry and can be used in the manufacture of structures made of concrete and reinforced concrete on a caustic base in a tense one.

The aim of the invention is to increase the crack resistance of the bone.

Example. Domain granish chemical composition, May.%: SiO 35.5836, 5; Al.Oj 7.15-7.19, - 1.79- 1.81; CaO 41.92-42.17; Hp, 0 3.02- 3.20; 0.69-0.72; 0.17-0.20; SOj 3.54-3.72; the losses during the calcination of the rest are subjected to a pier to S 3000-3200. An aqueous solution of alkaline melt with a density of 1.25 g / cm is used as the P-acne component. In addition, the concrete mix contains crushed granite fractions of 5–10 mm, quartz sand with p-L2, crushed expanded clay gravel, agloporite, burnt coal rock, ash and slag fuel waste, and ash from the power plants.

The chemical composition of the used ceramic materials is given in table. one .

The granulometric composition of the ashes is 30 00 col./min and amplitude O, 1-0.4 mm.

In the table of 2

Grade A grade A polyisocyanate is a mixture of diphenylmethanediisocyanate and high molecular weight polyisocyanates used in the manufacture of foams, linoleum, film coatings, hydro-insulation mixtures and other polymeric building materials. Polyisocyanate is a dark liquid with a specific odor, density at

3

20 s

1.22-1.25 G / CM

Basic physico-chemical characteristics of polyisocyanate. Content,%;

diphenylmethane diisocyanate73

isocyanate groups30

total chlorine 0.65

phenyl isocyanate 0.5

viscosity B 3-4, min3,5

In experiments with the consumption of polyisocyanate 0,2; 0.35 and 0.5 wt.% NCO-rpynn content is 0.06; 0.105 and 0.15 wt.%, Respectively. The polyisocyanate has a high reactivity due to the presence of a system of cumulated bonds — N C O.

Fly ash is used as a ceramic component for blending crushed ceramic coated materials and providing a module of a mixture size of 1.2-1.6 with a bulk nautical weight of 800-1100 k1 / m. (The type and ratio of the fractions of the ceramic components are not significant). In addition to these materials, it is possible to use shungizite, clay bricks and other porous ceramics.

The concrete mix is prepared as follows.

Forced or gravitational concrete mixers are fed with dosed aggregates, ground slag and sand fraction of ceramic materials, the solution of the alkaline component with the polyisocyanate previously added to it is stirred for 1-3 minutes and after 1.5–3 minutes after obtaining a homogeneous mass. finish mixing. The concrete mixture prepared in this way is placed in a mold and compacted using vibration equipment with a frequency of 28005

0

five

0

five

Hardening of concrete can be in natural conditions or when steaming in the chambers of a lot of type or other design at temperatures up to 90 ± t 5 C in the mode of 5 + 6 3.

For the test, prism samples of 7.07 × 7.07 × 22.0 cm are formed. Sample preparation for the evaluation of crack resistance includes the determination of shrinkage deformation and stretch.

The compositions and properties of concrete from the proposed and known mixtures are given in table. 3

The data on the effect of the content of polyisocyanate and fine aggregate (sand fraction) on the properties of concrete are given in the E table. 4 and 5, respectively.

Data on the effect of the modulus of fine-grained aggregate of ceramic materials on concrete properties are given in Table. 6

The particle size distribution of the sand fraction is given in Table. 7

As evidenced by tests, the introduction of a sand fraction of ceramic materials and polyisocyanates into the concrete makes it possible to increase the stretchability and crack resistance of heavy construction of alkali concrete. At the same time, the use of coarse and fine aggregates from dense rocks makes it possible to select a mineral skeleton with a sufficiently dense and durable structure. The introduction of porous ceramic material into the sand fraction reduces the initial shrinkage stresses in concrete, contributes to the compaction of cement stone and improves hardening conditions due to suction and accumulation of a certain amount of the alkaline component solution after compaction and its subsequent return during the period of concrete strength increase, and also increases de compare the properties of the conglomerate. Particles of a porous ceramic material, after being subjected to hydration to form a strong contact zone and a shell around them, possess

Higher elastic properties. in comparison with other components of concrete, they contribute to the increase in extensibility, cause the redistribution of stresses, and, consequently, increase the crack resistance of slag-alkali concrete. The use of the sand fraction of a porous ceramic material in an amount of less than 1 wt.% Does not provide the desired effect, and an increase in its content in excess of 3 wt.% As well as an increase in the grain size, although it increases stretchability and crack resistance, leads to a significant decrease in concrete strength. . The use of ceramic material with a bulk weight of more than 1100 kg / m is inefficient., And with

bulk weight less than 800 kg / m is not economically viable because of the cost subjected to crushing on .Р genuine aggregates.

The introduction of polyiso-45 into the concrete mix allows for the binding of a free state of a certain state of water to a free state after the concrete has hardened and to form elastic structures in the pores and cracks of the cement stone due to its high reactivity and the ability of the isocyanate to add mobile hydrogen atoms. The consequence of this is a reduction in shrinkage, an increase in elasticity, density and homogeneity, and ultimately, stretchability and crack resistance of concrete. The use of polyisocyanate in an amount less than

0.2 mai. The% does not have a significant effect on the formation of the properties of the conglomerate, and an increase in the content of 0.5% by weight leads to a decrease in the elastic modulus of the concrete.

Thus, the proposed concretes have a higher tenacity and crack resistance compared to the known ones. Of these, products and structures for the construction of roads, building foundations, underground utilities and non-production premises and a number of others can be made. JHbK reinforced concrete structures and monoliths are possible without changing the design sections of the elements and their reinforcement areas. It is most rational to use concretes in building structures operating under conditions of low humidity and elevated temperatures, under alternating effects of heating and cooling, wetting and drying, and under other conditions.

The economic efficiency of the proposed concretes is due to the low cost and prevalence of raw materials, high physicomechanical properties, durability, and simple production technology.

Claims (1)

Invention Formula Concrete mixture, including a fine blast furnace granpack, an aqueous solution of an alkaline alloy with f 1.25 g / cm, fine and coarse aggregate from dense rocks, which, in order to improve the fracture toughness, contains an additional polyiso dust clay, agloporite, burned mines for rock or ash and slag fuel waste in the following ratio of components, May.% Fine domain granptak An aqueous solution of sylochny melt with 1.25 g / cm Fine aggregate of dense rocks Polyisocyanate Fine aggregate groups of expanded clay “agglo-porite, burned mine rock or eoloshlakovy Expanded clay gravel 52.4-68.8 12.7-35.5 0.6-4.5 0.4-3.6 7.5-11.5 2.1-4.0 Else Agloporite 45.0-68.8 15.7-35.5 2.5-5.9 2.0-4.3 7.5-11.0 2.1-3.8 Else Burned mine rock 39.5-68.8 13.10-34,50,65-4,30,8-4,07,5-11,4 2,2-5,0 - Ash and slag fuel waste 42.0-64.5 15.2-33.60.9-4.4 0.4-3.28.0-12.8 2, G-3.9 Zola ash entrusted to CHP 39.5-62.7 13.6-35.52.8-5.9 1.5-4.38.5-12.8 2.1-3.5 -, iS ,. Full 2.2 12.8 25.5 44.3 70.3 100 1.5 1331852b fuel waste 1-3 Coarse aggregate from dense rocks Else Table 1 table 2 vO tN I fu 01 n at (P cfl S ac T a b j and c a A Table3 Order 3765/21 Circulation 587 VNIIPI USSR State Committee for inventions and discoveries. 1P035, Moscow, Zh-35, Raushsk nab. 4/5 Production and printing company, Uzhgorod, st. Project, 4 Table 6 Table Subscription