JPH09268042A - Concrete composition and concrete - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a concrete composition little in slump loss by adding blast furnace slag particles and a specific esterification product produced from a polyoxyalkylene derivative to a concrete composition. SOLUTION: This concrete composition comprises a concrete composition containing a cement, water, a fine aggregate and a course aggregate as main components, blast furnace slag particles in an amount of 50-400kg per m<3> of the concrete composition, and 0.1-10kg of the below-mentioned component F. The component F is an esterification reaction product obtained by esterifying the copolymer of a polyoxyalkylene derivative of formula I: R<1> O(A1 O)n R<2> [R<1> is a 2-5C alkenyl group; A<1> O is a 2-4C oxyalkylene group; R<2> is a 1-8C hydrocarbon group; (n) is 5-300] with maleic acid anhydride with a polyoxyalkylene derivative of formula II: R<3> O(AO)m H (R<3> is a 1-8C hydrocarbon group; A<2> O is a 2-4C oxyalkylene group; (m) is 1-200] in such a condition that the ratio of the number of the maleic anhydride residues in the copolymer to the number of the hydroxyl groups in the compound of formula II is 1:0.1 to 1:1.5, or a salt of the esterification reaction product.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a concrete composition and concrete. More specifically, it relates to a concrete composition having excellent slump loss prevention property and containing blast furnace slag fine powder, and high-strength concrete obtained by curing the same.

[0002]

2. Description of the Related Art Concrete has the characteristics of high strength, freedom of shaping, excellent fire resistance, corrosion resistance, etc. In addition, it can be mass-produced, is cheap and easy to use, and is easy to use. Since it has many excellent features as a product such as, there is currently no construction material superior to this, and it is used in large quantities. In recent years, with the increase in the thickness and size of concrete structures, there has been an increasing demand for higher strength of concrete. In order to increase the strength of concrete, it is necessary to increase the hydraulic components such as cement in the concrete composition and decrease the water content, but since the viscosity after kneading the concrete composition increases, a water reducing agent, etc. Additives are needed. Furthermore, with the development of highly fluidized concrete, the performance requirements for water reducing agents have become even higher. As the water reducing agent, a naphthalene sulfonic acid formaldehyde condensate salt, a melamine sulfonic acid formaldehyde condensate salt, a lignin sulfonic acid salt, a polycarboxylic acid compound, or the like is used.
The naphthalene sulfonic acid formaldehyde condensate salt and the melamine sulfonic acid formaldehyde condensate salt have a large slump loss, and the water reducing property cannot be said to be sufficient. Lignin sulphonate has insufficient water reduction. for that reason,
In many cases, polycarboxylic acid type water reducing agents are used.

Usually, in concrete composition, cement of the component (A) is about 200 to 1 m ^{3 of} the concrete composition.
600 kg, the component (B) water is 100 to 185 kg, the component (C) fine aggregate is 400 to 1200 kg, and the component (D) coarse aggregate is 400 to 1200 kg as a main component. On the other hand, as one of the reuses of industrial waste, blast furnace slag fine powder generated from an iron mill is used as a part of these concrete compositions. For example, it is disclosed in "Hyperformance Concrete", pages 51-65 (1993) by Kogakudo Shuppan, Okamura, Maeda, and Ozawa. However, the amount used is a part of the generated blast furnace slag fine powder, and more use is desired. When the blast furnace slag fine powder is used as a part of the concrete composition, even when the polycarboxylic acid-based water reducing agent is used, there is a drawback that the slump loss becomes large, which is the use of the blast furnace slag fine powder. It is one of the reasons why it is not done sufficiently. Therefore, there is a demand for a concrete composition that does not increase the slump loss even when a large amount of blast furnace slag fine powder is mixed and that maintains high strength.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a concrete composition containing a large amount of blast furnace slag fine powder and having a small slump loss, and a high-strength concrete obtained by hardening the same.

[0005]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that blast furnace slag fine powder is copolymerized with a specific polyoxyalkylene derivative and maleic anhydride. It was found that a concrete composition containing the above-mentioned copolymer and a reaction product of a specific polyoxyalkylene derivative gives concrete having a small slump loss and high strength, and completed the present invention. That is, the present invention relates to (1) a concrete composition containing (A) cement, (B) water, (C) fine aggregate and (E) coarse aggregate as main components, in 1 m ³ of the concrete composition: E) 50 to 400 kg of blast furnace slag fine powder, and (F) the following general formula (1) R ¹ O A ¹ O) _n R ² (1) (where R ¹ is an alkenyl group having 2 to 5 carbon atoms, A ¹ O is an oxyalkylene group having 2 to 4 carbon atoms, n = 5 to 300,
R ² represents a hydrocarbon group having 1 to 8 carbon atoms. Further, 50 mol% or more of the oxyalkylene group is an oxyethylene group. ) A polyoxyalkylene derivative and a maleic anhydride copolymer represented by the following general formula (2) R ³ O (A ² O) _m H (2) (wherein R ³ has 1 to 8 carbon atoms). A hydrocarbon group, A ² O represents an oxyalkylene group having 2 to 4 carbon atoms, and m = 1 to 200), and a polyoxyalkylene derivative represented by Formula (2)
The ratio of the number of hydroxyl groups in the polyoxyalkylene derivative is 1:
A concrete composition comprising 0.1 kg to 10 kg of an additive consisting of a reaction product esterified with 0.1 to 1: 1.5 or a salt thereof. Furthermore, (2) a concrete obtained by curing the concrete composition.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The concrete composition of the present invention is
Concrete that does not harden yet, JISA1138
It has a property that it can be blended according to "how to make concrete in a test room" and can be analyzed according to JIS A1112 "Method of washing analysis test for concrete that does not harden yet".

In the present invention, the concrete composition includes 100 to 500 kg of the cement of the component (A) and 100 to 1 g of the water of the component (B) in 1 m ^{3 of} the concrete composition.
85 kg, component (C) fine aggregate is 400-1200 kg
And the coarse aggregate of the component (D) contains 400 to 1200 Kg as a main component. Examples of the component (A) cement used in the present invention include ordinary Portland cement, early strength cement, low heat cement, and high belite cement. A composition in which silica fume or the like is mixed can also be used. In the compositions of the present invention, the cement 100~500kg in the concrete composition 1m ³ is incorporated, the amount of cement concrete compositions 1m ³ is less than 100 kg, the strength of the concrete becomes insufficient preferably Absent.
The amount of cement in 1 m ^{3 of} concrete composition is 500 k
If it exceeds g, more heat will be generated due to hardening of cement,
It is not preferable because the drying shrinkage becomes large and cracks easily occur.

In the composition of the present invention, the water of the component (B) is 100 to 185 kg in 1 m ^{3 of} the concrete composition.
However, if the amount of water in 1 m ^{3 of} the concrete composition is less than 100 kg, it may be difficult to mix the concrete composition or the flow may decrease. The amount of water in 1 m ^{3 of} concrete composition is 185 k
If it exceeds g, the strength of the concrete becomes insufficient. In the present invention, the amount of water in the concrete composition is particularly important, so if the fine aggregate or coarse aggregate to be blended is not in a surface-saturated state of water saturation, quantify the water content and actually blend. A correction must be made to the amount of water.

The fine aggregate of the component (C) used in the present invention is an aggregate which passes through a 10 mm mesh sieve defined by JIS A0203 and passes through a 5 mm mesh sieve in an amount of 85% or more by mass. Aggregates include river sand, land sand, mountain sand, sea sand, and crushed sand. In the composition of the present invention, 400 to 1200 kg of fine aggregate is mixed in 1 m ^{3 of} the concrete composition. The amount of fine aggregate in 1 m ^{3 of} concrete is 40
If it is less than 0 kg, the coarse aggregate easily separates, and the workability such as transportation, driving, compaction, and finishing is deteriorated. The amount of fine aggregate in 1 m ^{3 of the} concrete composition is 120
When it exceeds 0 kg, workability is impaired again.

The coarse aggregate of the component (D) used in the present invention is an aggregate that stays in a 5 mm mesh sieve defined by JIS A0203 in an amount of 85% or more by mass. Such aggregate includes river gravel. , Land gravel, mountain gravel, crushed stone, etc. In the composition of the present invention, 400 to 1200 kg of coarse aggregate is mixed in 1 m ^{3 of} the concrete composition. If the amount of coarse aggregate in 1 m ^{3 of} concrete is less than 400 kg, the strength of the concrete may decrease. If the amount of coarse aggregate in 1 m ^{3 of the} concrete composition exceeds 1200 kg, workability is impaired. In the composition of the present invention, the weights of the fine aggregate and the coarse aggregate are weights in a surface-dried saturated state. It is necessary to select the types and amounts of the fine aggregate and the coarse aggregate to be added to the concrete composition in consideration of an appropriate balance such as economical efficiency, heat generation during curing, drying shrinkage, and aggregate separation.

The blast furnace slag fine powder of component (E) used in the composition of the present invention is produced from blast furnace slag generated in an iron mill. Usually, the blast furnace slag fine powder has a Blaine value (specific surface area) of 3,000 to 10,000 cm ² / g,
When used in the present invention, it can be appropriately selected and used. In the compositions of the present invention, blast furnace slag is 50~400kg in the concrete composition 1m ³ is incorporated, the amount of blast furnace slag concrete composition 1m ³ is less than 50 kg, the The purpose of the invention is not met and workability is reduced. When the amount of blast furnace slag fine powder in 1 m ^{3 of the} concrete composition exceeds 400 kg, the initial strength of the concrete becomes insufficient.

In the general formula (1), R ¹ has 2 to 2 carbon atoms.
5 is an alkenyl group, and examples of such an alkenyl group include a vinyl group, an allyl group, a methallyl group, and 3-
Examples thereof include butenyl group, 4-pentenyl group, 3-methyl-3-butenyl group and the like. When the alkenyl group represented by R ¹ has more than 5 carbon atoms, the copolymer obtained has insufficient hydrophilicity.

In the general formula (1), R ² has 1 to 1 carbon atoms.
8 is a hydrocarbon group, and examples of such a hydrocarbon group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a t-butyl group, an amyl group, an isoamyl group, and a hexyl group. , Heptyl group, octyl group, cyclohexyl group, phenyl group, benzyl group,
Examples thereof include a tolyl group and a phenethyl group. R ²
When the number of carbon atoms of the hydrocarbon group represented by is greater than 8, the hydrophilicity of the resulting copolymer becomes insufficient.

In the general formula (1), A ¹ O has 2 carbon atoms.
To oxyalkylene groups of 4 to 4, and examples of such an oxyalkylene group include an oxyethylene group, an oxypropylene group, an oxybutylene group, and an oxytetramethylene group. When the oxyalkylene group represented by A ¹ O is an oxymethylene group, the compound represented by the general formula (1) is unstable, and harmful formaldehyde is generated by decomposition, which is not preferable. When the number of carbon atoms of the oxyalkylene group represented by A ¹ O exceeds 4, the hydrophilicity of the compound represented by the general formula (1) becomes insufficient. In the compound represented by the general formula (1) used in the composition of the present invention, 50 mol% or more of oxyalkylene groups are oxyethylene groups. When the oxyethylene group in the oxyalkylene group is less than 50 mol%, the water solubility becomes insufficient and the performance as a water reducing agent deteriorates.

In the general formula (1), the value of n is 5 to 30.
0. When the value of n is less than 5, the setting delay becomes large, and when the value of n exceeds 300, the viscosity becomes high and the production becomes difficult.

The copolymer of the polyoxyalkylene derivative represented by the general formula (1) and maleic anhydride is obtained by combining the polyoxyalkylene derivative of the general formula (1) and maleic anhydride with a peroxide initiator, It can be easily obtained by copolymerizing using an azo initiator or the like by a known method. At that time, a solvent such as benzene, toluene, and xylene can be used. Further, a copolymer obtained by adding another copolymerizable monomer such as styrene or vinyl acetate at the time of copolymerization can also be used in the composition of the present invention. The molar ratio of the polyoxyalkylene derivative represented by the general formula (1) and maleic anhydride is 3: 7.
˜7: 3 is preferred, especially about 1: 1.

When the polyoxyalkylene derivative represented by the general formula (1) is copolymerized with maleic anhydride, the water content in the system is 1% by weight or less based on the total amount of the polyoxyalkylene derivative and maleic anhydride. Preferably. When the water content in the system is more than 1% by weight of the total amount of the polyoxyalkylene derivative and maleic anhydride, the copolymer and the general formula (2)
It is not preferable because the reactivity with is deteriorated.

In the general formula (2), R ³ has 1 to 1 carbon atoms.
8 is a hydrocarbon group, and examples of such a hydrocarbon group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a t-butyl group, an amyl group, an isoamyl group, and a hexyl group. Saturated hydrocarbon groups such as heptyl group and octyl group; allyl group, butenyl group,
An unsaturated hydrocarbon group such as a pentenyl group; a cyclic hydrocarbon group such as a cyclohexyl group, a phenyl group, a benzyl group, a tolyl group, a phenethyl group, and the like can be given. When the hydrocarbon group represented by R ³ has more than 8 carbon atoms, a copolymer of the polyoxyalkylene derivative represented by the general formula (1) and maleic anhydride and the polyoxyalkylene represented by the general formula (2) are used. The hydrophilicity of the additive, which is a reaction product of the derivative, becomes insufficient.

In the general formula (2), A ² O has 2 carbon atoms.
~ 4 oxyalkylene groups, and examples of such oxyalkylene groups include the same as the above A ¹ O. When the oxyalkylene group has more than 4 carbon atoms, a reaction product of the copolymer of the polyoxyalkylene derivative represented by the general formula (1) and maleic anhydride and the polyoxyalkylene derivative represented by the general formula (2). The foamability of the additive is increased.

In the general formula (2), the value of m is 1 to 20.
0. If the value of m exceeds 200, the performance as a water reducing agent deteriorates. The reaction product of the copolymer of the polyoxyalkylene derivative represented by the general formula (1) and maleic anhydride and the polyoxyalkylene derivative represented by the general formula (2) is the polyoxyalkylene derivative represented by the general formula (1). Copolymer of oxyalkylene derivative and maleic anhydride and general formula (2)
It can be easily obtained by mixing with a polyoxyalkylene derivative represented by the formula (1) under heating without a catalyst or by mixing in the presence of a catalyst at room temperature or under heating.

In the reaction, esterification is carried out when the molar ratio of the number of maleic anhydride residues in the copolymer to the number of hydroxyl groups of the polyoxyalkylene derivative of the general formula (1) is 1: 0.1 to 1: 1.5. Examples of the catalyst include sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium methylate, ammonia, monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine and the like.

The salt of the reaction product of the copolymer of the polyoxyalkylene derivative represented by the general formula (1) and maleic anhydride and the polyoxyalkylene derivative represented by the general formula (2) is, for example, water. Alkali metal salts obtained by neutralizing with sodium oxide, potassium hydroxide, etc .; Alkaline earth metal salts obtained by neutralizing with calcium hydroxide, magnesium hydroxide, etc .; Monoethanolamine, diethanolamine, triethanolamine And amine salts obtained by neutralization with ammonia; ammonium salts obtained by neutralization with ammonia.

In the composition of the present invention, the compound represented by the general formula (1)
An additive consisting of a reaction product of a copolymer of a polyoxyalkylene derivative represented by the formula and maleic anhydride and a polyoxyalkylene derivative represented by the general formula (2) or a salt thereof is added to 1 m ^{3 of} the concrete composition. 0.1-10k
g, preferably 0.4 to 5 kg. If the content of the additive in 1 m ^{3 of the} concrete composition is less than 0.1 kg, a sufficient slump loss preventing effect cannot be obtained. The compounding amount of the additive in 1 m ^{3 of the} concrete composition is 10 k.
Even if it exceeds g, the improvement of the effect commensurate with the increase of the compounding amount cannot be obtained.

In the concrete composition of the present invention, other components such as naphthalenesulfonic acid formalin condensate salt, melamine sulfonic acid formaldehyde condensate salt, polycarboxylic acid type compound, etc. may be used as long as the performance of the composition of the present invention is not impaired. Additives, or other defoaming agents, air entraining agents, rust preventives, setting accelerators, setting retarders and the like can be added.

The concrete composition of the present invention can be kneaded by using a known mixer such as a batch mixer or a continuous mixer, but it is preferable to use a batch mixer such as a biaxial forced kneading mixer or a tilting mixer. You can The concrete composition of the present invention can be used as fresh concrete, concrete for secondary products, and the like. The concrete composition of the present invention can be used for various fluidity concretes such as super-hard concrete and high-fluidity concrete, but is particularly excellent for high-fluidity concrete having a slump flow of 40 cm or more.

[0026]

The concrete composition of the present invention has little slump loss even when a large amount of blast furnace slag fine powder is mixed. Further, the hardened concrete of the present invention has high strength.

[0027]

EXAMPLES The present invention will be described in more detail with reference to the following examples. The values in the table are the values corrected by measuring the water content of fine aggregate and coarse aggregate. The slump flow and compressive strength were measured by the following methods. (1) Slump flow: In accordance with JIS A1101,
After filling the slump cone with the concrete composition, the slump cone is gently pulled up vertically and allowed to stand until the concrete composition stops flowing. Then, the diameter of the spread of the concrete composition is measured at two points, which are the maximum value and the direction perpendicular to the maximum value, and the average value is taken as the slump flow value. The symbol (-) in the table indicates that the slump flow value was so bad that the test was stopped halfway. Each component in the table was placed in a forced kneading mixer, kneaded for 3 minutes and then taken out, and the slump flow immediately after mixing was measured. Transfer to a tilting mixer, mix at 2 revolutions per minute,
The slump flow was measured after 30 minutes, 60 minutes, and 90 minutes. (2) Compressive strength; 2 after molding according to JIS A1108
The compressive strength of the concrete after 8 days was measured.

Example 1 315 kg of Portland cement as the component (A), 170 kg of water as the component (B), and sand 79 as the component (C).
0 kg, gravel 894 kg as component (D), component (E)
As blast furnace slag fine powder (Blaine value 4000) 135
1.80 of the additive 1 of Table 2 as kg and component (F).
A concrete composition was obtained by placing kg in a forced kneading mixer and mixing for 3 minutes.

Examples 2 to 18 and Comparative Examples 1 to 10 Component (F) of the present invention shown in Table 2 using the copolymer shown in Table 1 as a raw material in the same manner as in Example 1. Additives 1 to 8 and other additives a to d shown in Table 3 are used to mix concrete compositions with the composition shown in Tables 4 and 2 and 5 and 1 and 2. did. In addition, Example 2
9, Comparative Examples 1 to 5 use blast furnace slag fine powder (Blaine value 4000) as the component (E), and Examples 10 to 18,
Comparative Examples 6 to 10 used blast furnace slag fine powder (Blaine value 6000) as the component (E). The results measured by the above test method are shown in Table 4-1, -2, Table 5-1, -2.
It was shown to.

[0030]

[Table 1]

[0031]

[Table 2]

[0032]

[Table 3]

[0033]

[Table 4]

[0034]

[Table 5]

[0035]

[Table 6]

[0036]

[Table 7]

From the above results, the concrete composition of the present invention has less slump loss than the concrete compositions of Comparative Examples and has sufficient fluidity, and the concrete after curing has sufficient compressive strength. I understand. That is, Examples 1 to 9 using the additive used in the present invention,
Nos. 10 to 18 have high slump flow values, whereas in Comparative Examples 1 and 6 using the copolymer alone and the additive which did not react with the general formula (2), the slump flow values were found to change with time. In Comparative Examples 2 and 7 using the additive having a hydroxyl group at the terminal of the general formula (1), the slump flow value decreases with time. Further, in Comparative Examples 3 and 8 in which the methacrylic acid-based additive was used, the slump flow value further decreased with time. Furthermore, in Comparative Examples 4 and 9 in which the naphthalene sulfonic acid-based additive was used, the fluidity disappeared in the middle of time, and in Comparative Examples 5 and 10 in which the additive was not used, the slump flow value was low and the fluidity was in the middle. You can see that there is no sex.

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Claims (2)

[Claims] 1. A concrete composition comprising (A) cement, (B) water, (C) fine aggregate and (E) coarse aggregate as main components, wherein (E) blast furnace slag in 1 m ³ of the concrete composition. 50 to 400 kg of fine powder, and (F) the following general formula (1) R ¹ O (A ¹ O) _n R ² (1) (wherein R ¹ is an alkenyl group having 2 to 5 carbon atoms, A ¹ O is An oxyalkylene group having 2 to 4 carbon atoms, n = 5 to 300,
R ² represents a hydrocarbon group having 1 to 8 carbon atoms. Further, 50 mol% or more of the oxyalkylene group is an oxyethylene group. ) A polyoxyalkylene derivative and a maleic anhydride copolymer represented by the following general formula (2) R ³ O (A ² O) _m H (2) (wherein R ³ has 1 to 8 carbon atoms). A hydrocarbon group, A ² O is an oxyalkylene group having 2 to 4 carbon atoms, and polyoxyalkylene derivative represented by m = 1 to 200) and the number of maleic anhydride residues in the copolymer and the general formula The ratio of the number of hydroxyl groups in the polyoxyalkylene derivative of (2) is 1: 0.
A concrete composition comprising 0.1 kg to 10 kg of an additive consisting of a reaction product esterified with 1 to 1: 1.5 or a salt thereof. 2. A concrete obtained by curing the concrete composition according to claim 1.