JP2696647B2 - How to make flowing concrete - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing flowing concrete.

[0002]

2. Description of the Related Art Soft-concrete concrete used for construction has a long history, and there is a history of using slump 24 cm concrete. Soft-mixed concrete has high fluidity, is easy to compact, is easy to pour into complicated parts such as column and beam connections, and hardly produces nests and beans.

[0003] In concrete work, recently, as a method of improving the durability of a structure by avoiding the problem of cracks due to an increase in unit water volume due to depletion of high-quality aggregate and the accompanying drying shrinkage, recently, stiffening has been carried out. Fluidized concrete was used in each region to obtain the same quality as concrete by softening concrete.

[0004]

However, the conventional fluidized concrete has a low viscosity of cement paste and poor workability after fluidization if coarse aggregate has a poor grain shape. When the amount of fine particles was small, material separation was liable to occur, and abnormal breathing sometimes occurred.

[0005] In addition, if the slump after fluidization is increased, the fluidity generally improves. However, in the case of a member with complicated reinforcement, defects such as cavities, bean boards, junkers and the like are generated, which may cause deterioration in quality. In principle, it was necessary to compact them carefully.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to obtain a flowing concrete having a good fluidity and a good filling property so that a high-quality concrete structure can be constructed even with a slight compaction.

[0007]

According to the present invention, a slump of 23 cm to 27 cm and a slump of 23 cm to 27 cm are added to a concrete mix by adding the following cement dispersant (A) and the following water-soluble polymer (B). A method for producing a flowing concrete having a flow height between 40 cm and 70 cm and a box height difference H of 8 cm or less according to the box filling test method described herein.

Cement dispersant (A): one or more selected from the group consisting of polycarboxylic acid polymer compounds, aromatic aminosulfonic acid polymer compounds, and formalin condensate compounds of melamine sulfonate , Water-soluble polymer (B): a water-soluble polymer having a molecular weight of 50,000 to 500,000 obtained by copolymerizing 25 to 75 mol% of the compound of the formula 1 and 75 to 25 mol% of the compound of the formula 2 Polymer.

[0009]

Embedded image (Wherein, R ₁ represents H or a lower alkyl group, Y represents H, an alkali metal, NH ₄ or an organic base)

[0010]

Embedded image (Wherein, R ₂ represents H or a lower alkyl group, A represents H or —CH ₂ OH)

In this case, the amount of the cement dispersant (A) is 0.10 to 0.60% by weight in the case of a polycarboxylic acid-based polymer compound in terms of solid content based on the mass of the cement, and in the case of an aromatic aminosulfonic acid-based polymer compound. Is used in the range of 0.30 to 1.50% by weight, and in the case of formalin condensate of melamine sulfonate, in the range of 0.20 to 1.40% by weight. 0.015 ~
It is better to use in the range of 0.50%.

[0012]

[Function] By using the admixture, it is possible to obtain a flowing concrete having excellent fluidity and separation resistance, and requiring less labor for compaction and compaction.

The cement dispersant (A) containing a polycarboxylic acid polymer compound, an aromatic aminosulfonic acid polymer compound or a formalin condensate compound of melamine sulfonate as a main component can be added in a large amount. It is a high-performance water reducing agent with little delay in setting and hardening.

Among the cement dispersants (A), examples of polycarboxylic acid-based polymer compounds include copolymers of α, β-unsaturated dicarboxylic acids and olefins, polyethylene glycol monoallyl ether and maleic acid-based monomers. And copolymers derived by further adding monomers copolymerizable therewith, polyalkylene glycol mono (meth) acrylate and (meth) acrylate monomers, and And copolymers derived from monomers that can be copolymerized. Commercial products include Aqualock FC-600 (trade name, manufactured by Nippon Shokubai Co., Ltd.) and Sunflow HS700 (trade name, manufactured by Sanyo Kokusaku Pulp Co., Ltd.).

Among the cement dispersants (A) , examples of the aromatic aminosulfonic acid-based polymer compound include, for example, a co-condensate of sulfanilic acid and formalin, a co-condensate of sulfanilic acid with phenol and formalin, or And copolymers derived from monomers copolymerizable with sulfanilic acid. Commercial name Palic F
P200 (manufactured by Fujisawa Pharmaceutical Co., Ltd.).

Among the cement dispersants (A) , as a formalin condensate-based compound of melamine sulfonate, Melment F-10 (manufactured by Showa Denko KK), Nissan S
Some are commercially available under trade names such as MF (manufactured by Nissan Chemical Industries, Ltd.).

The amount of the cement dispersant (A) used is 0.10 to 0.60% by weight in terms of solid content based on the mass of cement, and 0.10 to 0.60% by weight for the polycarboxylic acid type polymer compound and 0.30 to 1.50% for the aromatic aminosulfonic acid type polymer compound. % By weight of the formalin condensate compound of melamine sulfonate is preferably in the range of 0.20 to 1.40% by weight.

The water-soluble polymer (B) is obtained by copolymerizing the compound of the formula 1 and the compound of the formula 2, and as a preferable example of the compound of the formula 1,
Acrylic acid, methacrylic acid, and salts thereof, and preferred examples of the compound of Formula 2 include acrylamide and methacrylamide.

The water-soluble polymer (B) is obtained and compound 25 to 75 mol% of the chemical formula 1, and a 75-25% reduction <br/> compound represented by Formula 2 by copolymerizing Molecular weight 50
000 to 500,000, preferably 100,000 to 20
It consists of a water-soluble copolymer having 0000. Method for producing a water-soluble copolymer by known methods, in the presence of a polymerization modifier according to the presence of a radical initiator or necessary, co-compounds represented by compound Formula 2 represented by the chemical formula 1 Obtained by polymerization.

The amount of the water-soluble polymer (B) to be used is preferably 0.015 to 0.50% in terms of solid content based on the mass of cement.

The cement dispersant (A) and the water-soluble polymer (B) may be separately added at the time of mixing and kneading the concrete, but those containing both (A) and (B) may be mixed with the concrete. It may be added to water. Further, in addition to (A) and (B), other AE water reducing agents such as ligninsulfonic acid and gluconic acid can be used in combination.

The use of the admixture according to the invention results in a slump of 23 cm to 27 cm, a slump flow of 40 cm to 70 cm and a difference in box height H of less than 8 cm according to the box filling test described in the following examples. It is possible to obtain flowing concrete.

[0023]

EXAMPLES The materials used, test items and methods are as follows. 1. Materials used (1) Cement: ordinary Portland cement Specific gravity = 3.
16 (2) Fine aggregate: river sand specific gravity = 2.62 crushed sand specific gravity = 2.
59 (3) Coarse aggregate: crushed stone Specific gravity = 2.64, Maximum dimension = 20mm

(4) Cement dispersant (A) Polycarboxylic acid-based polymer compound (abbreviated as PC): trade name containing a copolymer of polyethylene glycol monoallyl ether and maleic acid-based monomer as a main component Sunflow H
S700 (manufactured by Sanyo Kokusaku Pulp Co., Ltd.) was used. -Aromatic aminosulfonic acid polymer compound [abbreviated as AS]: PARIC FP-200 (manufactured by Fujisawa Pharmaceutical Co., Ltd.) having sulfanilic acid / phenol cocondensate as a main component was used. -Formalin condensate compound of melamine sulfonate:
[Abbreviated as MS]: Merment F-10 (trade name, manufactured by Showa Denko KK) was used.

(5) Water-soluble polymer (B) A copolymer of sodium acrylate (50 mol.%) / Acrylamide (50 mol.%) Having a molecular weight of 190,000 (abbreviated as PA) was used (Daiichi Kogyo Seiyaku Co., Ltd.) Co., Ltd.).

2. Test Items and Methods The concrete of the composition shown in Table 1 was evaluated for workability by the following three tests, and the air volume and compressive strength were measured.

(1) Slump test: According to JIS A1101.

(2) Slump flow test: In accordance with the manual for non-separable concrete in water.

(3) Fillability test: As shown in FIGS. 1 to 3, a cylinder 1 and a cylinder 2 having an opening area of 15 × 15 cm and a height of 40 cm are placed in a box 1 having a height of 40 cm. Are formed adjacent to each other. The partition plate 2 is attached from a position 7.5 cm away from the bottom surface, thereby forming an opening 3 through which the cylinder A and the cylinder B communicate at the bottom. The opening area of the opening 3 is 15
× 7.5 cm. A vertical slide plate 4 for opening and closing the opening 3 is attached. In the test, as shown in FIG. 2, the opening 3 was closed with the slide plate 4 and concrete was filled in the cylinder a. Immediately after filling, the slide plate 4 was pulled up as shown in FIG. Concrete flows into the cylinder through the pipe. The difference H (cm) between the concrete heights of the cylinders a and b after the inflow is obtained. It is evaluated that the smaller H is, the better the filling property is.

The air volume test conformed to JIS A 1128, and the compressive strength test conformed to JIS A 1108.

Table 1 shows the concrete composition and the test results.

[0032]

[Table 1]

As a result of this test, the following became clear. (1) As in the operational effects Comparative Examples 2-5 of usage and water-soluble polymer cement dispersant, a cement dispersant alone, only the fluidity of the cement paste increases when make increase the amount of crude There is a tendency for aggregate to separate, and the fillability also decreases. On the other hand, as shown in Examples 6 to 9, when the amount of the water-soluble polymer used is kept constant and the cement dispersant is increased, the tendency of coarse aggregate to separate is eliminated, and the filling property is improved.

(2) Influence of Cement Dispersant and Water-Soluble Polymer on Fine Aggregate Type As shown in Examples 10 and 11, crushed sand was mixed with river sand as fine aggregate by 30% and 50%. Even in this case, good fluidity and filling properties can be obtained by using a cement dispersant and a water-soluble polymer in combination. (3) Types of Cement Dispersant and Effects of Water-Soluble Polymer As shown in Examples 7, 12, and 13, even when any of the dispersants according to the present invention is used together with the water-soluble polymer, good results are obtained. Fluidity and filling are obtained.

(4) Effect of cement dispersant and water-soluble polymer on the type of concrete mix As shown in Examples 7, 14, and 15, even in concrete mixes having different water-cement ratios, the cement dispersant and water-soluble By using a polymer together, good fluidity and filling properties can be obtained.

[0036]

As described above, the cement dispersant (A)
The admixture containing both water and the water-soluble polymer (B) has a slump of 23 cm to 27 cm, a slump flow of 40 cm to 70 cm, and a box height difference H of less than 8 cm in the filling test, without causing setting retardation. This is extremely effective for obtaining a flowing concrete with excellent fluidity and separation resistance.

[Brief description of the drawings]

FIG. 1 is a plan view of a box for a filling test.

FIG. 2 is a box cross-sectional view showing a state during the filling test.

FIG. 3 is a box sectional view showing a state in which a difference H between box heights in a filling test is obtained.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Packing test box 2 Partition plate 3 Lower opening 4 Upper and lower slide plate for opening and closing an opening

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical indication location C04B 24:26 24:30) 111: 62 (72) Inventor Koji Nagata 1551 Tohei, Higashimatsuyama-shi, Saitama ( 72) Inventor Koji Nakajima 1-7-15 Higashi Ueno, Taito-ku, Tokyo Inside Sanflow Co., Ltd. (72) Inventor Shinya Hiraishi 1-12-26 Goten, Hiratsuka-shi, Kanagawa Prefecture (72) Inventor Tetsuo Utsumi Chigasaki, Kanagawa Prefecture 1-10-28 Ichitakada (72) Inventor Hajime Takano 5-1-11-105 Higashihara, Zama City, Kanagawa Prefecture (56) References JP-A-62-70250 (JP, A) JP-A-3-80140 (JP) , A) JP-A-5-17192 (JP, A) JP 2-7900 (JP, B2)

Claims (4)

(57) [Claims] 1. A slump of 23 cm to 27 cm and a slump flow of 40 cm by adding the following cement dispersant (A) and the following water-soluble polymer (B) to a concrete mix.
A method for producing a flowing concrete having a box height difference H of 8 cm or less according to the box filling test method described in the text, and a cement dispersant (A): a polycarboxylic acid polymer compound, One or more selected from the group consisting of aromatic aminosulfonic acid polymer compounds and formalin condensate compounds of melamine sulfonate; water-soluble polymer (B): Compounds 25 to 75 of [Chemical Formula 1] A water-soluble copolymer having a molecular weight of 50,000 to 500,000, obtained by copolymerizing mol% and 75 to 25 mol% of the compound of the formula (2). Embedded image Embedded image 2. The cement dispersant (A) is 0.10 to 0.60% by weight in the case of a polycarboxylic acid polymer in terms of solid content based on the mass of cement, and in the case of an aromatic aminosulfonic acid polymer. Is 0.30 to 1.50% by weight, and 0.20 for melamine sulfonate formalin condensate compound
2. The method according to claim 1, wherein the amount is in the range of 1.40% by weight. 3. The method according to claim 1, wherein the water-soluble polymer (B) is used in an amount of 0.015 to 0.50% in terms of solid content based on the mass of cement. 4. The production method according to claim 1, wherein at least a part of the fine aggregate in the concrete mix is crushed sand.