SU1717594A1 - Raw stock for producing light concrete - Google Patents

Abstract

The invention relates to the technology for the preparation of concretes, and that light concrete for cementless cement makes it possible to increase the strength of lightweight concrete for cementless concrete. This is achieved by introducing into the raw mix containing ground quicklime, ground two-water gypsum, volcanic slag and water, ground fly ash of thermal power plants with the following content of components, wt.%: Quick hammer lime 12-14; hammer fly ash TPP 15-16; -milled two-water gypsum 3.5-4; volcanic slag 52-54; water the rest. Concrete strength after 7 days 4.65–4.96 MPa, after 28 days 7.11–8.67 MPa, after steaming 8.71–9.34 MPa; bulk weight 1350-1360 kg / m3. 3 tab.

Description

The invention relates to a technology for the manufacture of concrete, namely, light concrete on cementless concrete.

The purpose of the invention is to increase the strength of lightweight concrete after steaming.

It has been established that when the ash content is 15-16% of the concrete mix and the presence of ground two-water gypsum (CaS04 2H20), it is possible to obtain a concrete mixture intensively hardening and normal (normal conditions). The introduction of fly ash with an increased content of the two-water modification of calcium sulfate leads to a shift in the phase composition of the neoplasms towards the synthesis of new phases (such as: hydrosulfurite (2CaO-Al203cSi024mCaS04 pHZO), which in turn leads to an increase in the rate of hardening of concrete and concrete in normal conditions

The optimization of the composition of the raw mix was carried out as follows.

Composition-dosed components of uncemented solid; Quicklime, fly ash TPP. dihydrate gypsum was mixed and subjected to co-grinding before dry to a specific surface of 3000-35000 cm / g. The substance obtained was mixed in a certain proportion in composition with the aggregate - volcanic slag of a fraction of 0-5 mm and subsequently with water. Prepared raw mix of lightweight concrete fit into the form. A part of the samples were steamed according to the mode 2 + 10 + 2 h at 90 ° C, and the other part of the samples were hardened under normal conditions (t 20-25 ° C).

The results of testing samples of concrete are given in table 2.

As can be seen from the results shown in Table 2, the maximum value of strength after steaming has composition b, and after hardening, under normal conditions, composition 8. In general, it is clear that light-weight concrete compositions 3-8 have the highest results. The proposed composition of the raw mix for the manufacture of lightweight concrete is prepared as follows.

Quicklime, fly ash, dihydrate gypsum are mixed at the next salt content, wt.%: Lime limestone 12-14 Fly ash15-16

Two-water gypsum 3.5-4 Volcanic slag 52-54 Water Else

After that, the resulting mixture is subjected to joint grinding in a ball mill to a dispersion: the specific surface is 3000–3500 cm2 / g. The resulting cementless binder is mixed with a filler, a volcanic slag with a fraction of 0–5 mm. Then the shutter are blended with water. Mixed in mechanical mixers of forced action. Molded samples by vibration compaction. Part of the samples - cubes are subjected to steaming under the regime of 2 + 10 + 2 hours at 90 ° C: while the other part of the samples of concrete remain solidified under normal conditions at 20-25 ° C.

At the same time, as a result of steaming, lightweight concrete is synthesized with compressive strength of 8.71 - 9.34 MPa with a bulk weight of 1350-1360 kg / m3, and under normal conditions, the concrete has the following properties: strength at the age of 7 days is 4.65-4; 96 MPa, at the age of 28 days7,11-8,67 MPa, with the same bulk weight. (1350-1360 kg / m3).

Example 1. Quicklime taken into account in composition, fly ash of the TES, diversified gypsum (Ca304-2HgO) were crushed together in a ball mill (MBL type) to a specific surface of 3250 cm 1 t.

The cementless cement obtained was mixed dry. With a porous filler, a volcanic slag of a fraction of 0-5 mm.

Then, the resulting mixture was shut with water. The concrete mixture was mixed in a laboratory paddle mixer for 1.5 minutes. The mobility of the mixture was 0.8 cm, Az of the obtained mixture was molded by vibroplating for 1 min with a load of 2 kg / cm, cube samples of the size of cm. Half of the molded samples were subjected to steaming in a laboratory steaming chamber at 2 + 10 + 2 h at 90 ° C, the other part was left to harden during normal

conditions in a bath with a hydraulic shutter above water at 20 ° C.

The composition of the concrete dare with the following, wt.%: Hammer quicklime 12.5; hammer fly ash TPP 15.5; ground dzuvodny plaster 3,5; volcanic slag 53.5; water 15.

Results. Concrete strength after

steaming 8.83 MPa; with normal

0 conditions: after 7 days of hardening 4.65 MPa,

after 28 days of hardening 7.42 MPa, bulk

the mass of concrete is 1360 kg / m,

Example 2. A method for producing a concrete mix and making samples of concrete 5 is similar to Example 1.

The composition of the concrete dare with the following, wt.%:

Hammer quicklime lime 13

Hammer fly ash TPP 15.0 0 Ground crushed plaster 4

Volcanic slag 54

Water 14.0

Results, Concrete Strength After

steaming 9.13 MPa; with normal

5 conditions: after 7 days of hardening 4.96 MPa „

after 28 days of curing 7.63 MPa. Voluminous

the mass of concrete is 1358 kg / m,

Example 3. A method for producing a concrete mix and making samples of concrete 0 is similar to Example 1.

The composition of the concrete mix with the following, wt.%:

Hammer quicklime lime 14

Hammer fly ash T (C) 16

Ground two-water plaster 3,5

Volcanic slag 52

Water 14.5

Results. Concrete strength after

steaming 9.21 MPa; under normal conditions, after 7 days of hardening 4.81 MPa, after 28 days of hardening 8.67 MPa. The bulk density of concrete is 1360 kg / m. 0 The proposed composition of the concrete mixture was compared by technical essence with the prototype (Table 3).

From Table 3 it follows that the composition of the concrete according to the invention provides 5 a significant increase in the speed (5-6 times) of the curing of concrete under normal conditions at 20-25 ° C, and also leads to an increase of 25% in the strength of concrete after steaming . 0 Formula was invented and

Raw materials are emulsified for the manufacture of lightweight concrete containing ground burnt lime, ground silica-containing component, ground gypsum, volcanic slag, and water, which is abolished with the tag, which, in order to increase strength, it contains ground asphalt silica containing ground ashes of TES and as ground gypsum - ground two-water gypsum with the following ratio of components, wt.%: The hammer is quickened lime 12-14

Hammer fly ash TPP 15-16 Ground dzuvodny plaster 3.5-4L Volcanic slag 52-54 Water Else

Table 1

table 2

Claims (1)

20 claims Raw mix for the manufacture of lightweight concrete, containing ground quicklime, ground silica-containing component, ground gypsum, volcanic slag and water, characterized in that, in order to increase strength, it contains ground ash-bearing TPP as a ground silica-containing component and ground gypsum - ground two-water gypsum with the following ratio of components, wt.%: Ground quicklime 12-14 Ground fly ash TPP 15-16 Ground gypsum plaster 3.5-4 ,? Volcanic slag 52-54 Water Else S1 O 2 AI 2 About s F e 0 + F e g O 2 CaO ’ MDO K ₂ O No. gO Zoz ppp 1 54,2 18.1 13.5 3.0 2.1 2.1 1,1 Not detected Ostap b- | new | 1 T a b of persons a 2 Composition  Content of components, May L Volume- 1 Strength at Mr.—---- exhachations Lime Zolaunos Gypsum (2-aq) Volcanic slag Water N sz n MdGGd, kg / m? after steaming under normal conditions after, days 2.J 28 1 eleven * 17 3 55 14 1356 8.4 4.25 7.05 2 eleven 18 3 54 14 1355 8.34 4.1 6.71 3 12 fifteen 3,5 54 15,5 1356 8.71 4.8 ?, m ’ 4 12.9 15,5 3,5 ‘ 53.5 15.0 1356 8.83- 4.65 7.42 5 thirteen 15,5 4.0 53.5 ’ 14 1355 9.14 4.96 7.63 6 13.5 15,5 4 53 14 1354 9.34 ' 4.87 7.71 7 - 14 16 3,5 52,5 14 1352 9.05 4.74 7.96 8 14 16 3,5 52 14.5 1356 9.21 4.81 8.67 9 fifteen 14 2,5 56 12.5 1356 8.21 4.06 5.35 Table 3 Compressive strength of concrete hardening under normal conditions, MPa, after, su Strength of concrete after steaming, MPa 7 28 Bulk weight, kg / m ³ G Proposed 4.65 - 4.96 (4-5) 7.11 - 8.67 (5 - 7) 8.71 - (60 - 9.34 61) 1350 - 1360 Prototype 0.8 - 1,2 1,5  2,3 5.0 - 7.5 1350 - 1360 (4 - 5) (5 - 7) (60 - 61) Note. In brackets - energy consumption for hardening (thousand kcal / m ³ ) ₀