JP2918445B2 - Concrete manufacturing method - 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 concrete and, more particularly, to a method for producing concrete using carbonate-containing rock, which reduces slump loss of concrete and has improved workability.

[0002]

2. Description of the Related Art A large number of condominiums are being constructed in metropolitan areas such as the Tokyo metropolitan area. The transportation time required by consorts is increasing year by year.
Since the extension of the required time for transporting the concrete causes a decrease in the fluidity of the ready-mixed concrete and makes the construction difficult, there is a strong demand for concrete with a small so-called slump loss capable of maintaining the fluidity for a long time.

On the other hand, the use of limestone and other carbonate-containing aggregates as concrete aggregate has been increasing year by year, and this carbonate-containing aggregate has the advantage of increasing the compressive strength of concrete. Elutes and activates the initial hydration of the cement, the cement hardens faster,
It has the disadvantage of significantly increasing slump loss. The use of this carbonate-containing aggregate has spurred the loss of fluidity of the concrete over time.

[0004]

Conventionally, in order to obtain concrete with a small slump loss, a slump-loss-reducing type dispersant for concrete has been used. However, slump loss peculiar to concrete using carbonate-containing rock has been used. No effective material has been found, and the fluidity of concrete has not been ensured for a long time.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a concrete in which a part or the whole of aggregate is carbonate-containing rock, a naphthalenesulfonic acid formaldehyde condensate, a melaminesulfonic acid formaldehyde condensate, a methoxypolyethylene glycol monomethacrylic acid. Ester-methacrylic acid copolymer, sulfanilic acid-phenol formaldehyde co-condensate, sulfanilic acid-bisphenol formaldehyde co-condensate, lignin sulfonate, one or more dispersants for concrete and oxycarboxylic acid By using together with a dispersant for concrete containing an acid or its salt as a main component, we found a method to reduce the slump loss of concrete using carbonate-containing aggregate and maintain fluidity for 2 hours or more. The purpose,
It is the result of intensive research.

The present invention relates to a method for preparing a naphthalene sulfonic acid formaldehyde condensate, a melamine sulfonic acid formaldehyde condensate, a methoxypolyethylene glycol monomethacrylate-methacrylic acid copolymer, a sulfanyl, based on 1000 parts by weight of concrete-containing aggregate carbonate-containing rock. A dispersant for concrete containing one or more of acid / phenol formaldehyde cocondensate, sulfanilic acid / bisphenols formaldehyde cocondensate and lignin sulfonate, and oxycarboxylic acid or a salt thereof as a main component a concrete dispersant using total of 0.1 to 10 parts by weight, and naphthalene sulfonic acid formaldehyde condensates, melamine sulfonate formaldehyde condensate, methoxy polyethylene glycol monomethacrylate ester A methacrylic acid copolymer, a sulfanilic acid-phenol formaldehyde co-condensate, a sulfanilic acid-bisphenol formaldehyde co-condensate, a lignin sulfonate, or a dispersant for concrete containing one or more of lignin sulfonates as main components; This is a method for producing concrete in which the weight ratio with a concrete dispersant containing an acid or a salt thereof as a main component is 99: 1 to 1:99.

[0007] Aggregates for concrete, which are the subject of the present invention, are those in which part or all of them contain carbonate.
Its carbonate content is more than 10% by weight of the aggregate. The carbonate-containing aggregate is specifically limestone, mafic limestone, calcareous dolomite, dolomite, chalk, limestone, marlstone, crystalline limestone, lime schist. Further, the particle size distribution and the average particle size of the aggregate are not limited. In some cases, it is crushed to a particle size of cement particles and mixed with cement for use.

[0008] The concrete dispersant used in the present invention is a naphthalenesulfonic acid formaldehyde condensate, a melaminesulfonic acid formaldehyde condensate, a methoxypolyethylene glycol monomethacrylate-methacrylic acid copolymer generally used as a concrete dispersant. Products, sulfanilic acid / phenols formaldehyde cocondensate, sulfanilic acid / bisphenols formaldehyde cocondensate, lignin sulfonate, concrete dispersant and oxycarboxylic acid or salt thereof. It is a dispersant for concrete as a component.

Naphthalenesulfonic acid formaldehyde condensate, melaminesulfonic acid formaldehyde condensate, methoxypolyethylene glycol monomethacrylate-methacrylic acid copolymer, sulfanilic acid / phenol formaldehyde cocondensate, sulfanilic acid / bisphenol formaldehyde cocondensate The dispersant for concrete mainly containing one or more of lignin sulfonate and the dispersant for concrete mainly containing oxycarboxylic acid or a salt thereof is a total of 0.1 to 0.1 parts by weight of carbonate-containing rock. Use 10 parts by weight. If it is less than 0.1 part by weight, the fluidity of the concrete cannot be obtained. On the other hand, if the amount exceeds 10 parts by weight, the hardening of the concrete is inhibited, and the compressive strength is reduced.

Naphthalenesulfonic acid formaldehyde condensate, melaminesulfonic acid formaldehyde condensate, methoxypolyethylene glycol monomethacrylate-methacrylic acid copolymer, sulfanilic acid / phenol formaldehyde cocondensate, sulfanilic acid / bisphenol formaldehyde cocondensate The mixing ratio of a dispersant for concrete mainly containing one or two or more lignin sulfonates and a concrete dispersant mainly containing oxycarboxylic acid or a salt thereof is 99: 1 by weight.
１ ： 1: 99 is desirable. If the amount of the oxycarboxylic acid or its salt is less than 1 part by weight, the fluidity of the concrete cannot be sufficiently ensured, and if it exceeds 99 parts by weight, the concrete hardens and the compressive strength decreases. The oxycarboxylic acid or salt thereof is preferably a gluconate, more preferably sodium gluconate.

The concrete dispersant of the present invention is used in an amount of 0.01 to 1%, preferably 0.05 to 1%, more preferably 0.2 to 0.6% by weight based on cement.

Cement is usually Portland cement,
Early-strength Portland cement, moderately heated Portland cement, sulfate-resistant Portland cement, blast furnace cement, fly ash cement, silica cement, and low heat-generating cement are used. They can also be used in combination with admixtures such as silica fume and stone powder and other cement additives such as water reducing agents, air entrainers, setting accelerators, setting retarders, waterproofing agents and swelling agents.

[0013]

EXAMPLES The present invention will be described below with reference to examples.

The materials used and the composition of the concrete are as follows. Water (W): Tap water Cement (C): Asano ordinary Portland cement Specific gravity 3.16 Fine aggregate (S): Kimitsu land sand Specific gravity 2.60 FM 2.69 Coarse aggregate (G): Ube limestone Specific gravity 2.69 FM 6.92

[0015]

[Table 1]

The concrete dispersants used are shown below. Dispersant 1 Commercially available high-performance AE water reducing agent Sanflow HS-100 [contains naphthalenesulfonic acid condensate and ligninsulfonic acid derivative as main components, manufactured by Nippon Paper Industries Co., Ltd.]

Dispersant 2 Commercially available high performance AE water reducing agent Sanflow HS-200 [condensed aromatic sulfonic acid and lignin sulfonic acid derivative as main components, manufactured by Nippon Paper Industries Co., Ltd.]

Dispersant 3 Commercially available high-performance AE water reducing agent Sunflow HR-100 [Lignin sulfonic acid derivative as a main component, manufactured by Nippon Paper Industries Co., Ltd.]

Dispersant 4 Commercially available high-performance AE water reducing agent Sanflow HS-700 [polycarboxylate as a main component, manufactured by Nippon Paper Industries Co., Ltd.]

Dispersant 5 Commercially available high-performance AE water reducing agent Sanflow HS-40 [Melamine sulfonic acid condensate and lignin sulfonic acid derivative as main components, manufactured by Nippon Paper Industries Co., Ltd.]

Dispersant 6 A composition comprising a condensate of naphthalenesulfonic acid formaldehyde [manufactured by Mighty 150 Kao Corporation] and sodium gluconate [manufactured by Wako Pure Chemical Industries, Ltd.] in a weight ratio of solids of 60:40.

Dispersant 7 Melaminesulfonic acid formaldehyde condensate [SEICA M
FL Nippon Sika Co., Ltd.] and sodium gluconate described in Dispersant 6 in a solid content ratio of 70:30 by weight.

Dispersant 8 Methoxy polyethylene glycol monomethacrylate-methacrylic acid copolymer [Aqualoc FC600
S Nippon Shokubai Chemical Industry Co., Ltd.] and a 50:50 composition of sodium gluconate described in Dispersant 6.

Dispersant 9 Sulfanilic acid / phenol formaldehyde co-condensate [condensate prepared by the method described in Comparative Example 1 of JP-A-3-187960] and sodium gluconate described in Dispersant 6 in terms of solids weight ratio of 80 : 20 compositions

Dispersant 10 Formaldehyde condensate with 4-aminobenzenesulfonate and 2,2-bis (4-hydroxyphenyl) propane [condensate prepared by the method described in Example 1 of JP-A-3-187960] ] And sodium gluconate described in Dispersant 6 in a weight ratio of solid content of 50:50.

Dispersant 11 A composition of lignin sulfonate [Pearl Rex NL manufactured by Nippon Paper Industries Co., Ltd.] and sodium gluconate described in Dispersant 6 at a solids weight ratio of 60:40.

Dispersant 12 Condensation product of naphthalenesulfonic acid formaldehyde described in Dispersant 6

Dispersant 13 Melaminesulfonic acid formaldehyde condensate according to Dispersant 7

Dispersant 14 Methoxypolyethylene glycol monomethacrylate-methacrylic acid copolymer described in Dispersant 8

Dispersant 15 Sulfanilic acid / phenol formaldehyde cocondensate according to Dispersant 9

Dispersant 16 Formaldehyde condensate with 4-aminobenzenesulfonate and 2,2-bis (4-hydroxyphenyl) propane described in Dispersant 10

Dispersant 17 Lignin sulfonate described in Dispersant 11

Dispersant 18 Sodium gluconate described in Dispersant 6

In a 100 liter mixer, the materials and the respective dispersants of the kneading amount of 80 liters in the composition shown in Table 1 were charged and kneaded for 3 minutes, and the target slump was 20 cm and the target air amount was 4.5.
% Concrete was obtained. After that, the slump was measured at 30, 60, and 120 minutes. In addition, the slump and air amount of the concrete were measured based on JIS. Table 2 shows the obtained concrete test results.

[0035]

[Table 2]

Comparative Examples 1 to 5 show that conventionally used dispersants for concrete cannot secure the fluidity of concrete. On the other hand, Examples 1 to 6 show that the product of the present invention can maintain the fluidity of concrete for a long time. Further, Comparative Examples 6 to 11 show that the fluidity retention is insufficient when oxycarboxylic acid or a salt thereof is not blended, and Comparative Example 12 does not provide initial fluidity only with oxycarboxylic acid or a salt thereof. Alternatively, it indicates that there is a defect such as a decrease in compressive strength.

[0037]

By using the product of the present invention, it is possible to produce a concrete composition having better fluidity retention than conventional dispersants for concrete.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C04B 24:22 24:26 24:30) 103: 40 (72) Inventor Hiroyuki Kadoyama 1551 Tohei, Higashimatsuyama-shi, Saitama Nippon Paper Industries Co., Ltd. (72) Inventor Toshiaki Ichihara 1551 Higashihira, Higashimatsuyama-shi, Saitama Prefecture Nippon Paper Industries Co., Ltd. (56) Reference JP-A-59-69457 (JP, A) JP-A-59-207863 (JP, A) JP-A 5- 238798 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) C04B 28/02-28/08 C04B 14 / 28,24 / 06 C04B 24 / 18,24 / 22 C04B 24/26 , 24/30

Claims (1)

(57) [Claims] Claims: 1. Aggregate carbonate-containing rock for concrete 10
With respect to 00 parts by weight, naphthalenesulfonic acid formaldehyde condensate, melaminesulfonic acid formaldehyde condensate, methoxypolyethylene glycol monomethacrylate-methacrylic acid copolymer, sulfanilic acid / phenol formaldehyde cocondensate, sulfanilic acid / bisphenols formaldehyde A co-condensate, a dispersant for concrete containing one or more of lignin sulfonates as a main component, and a dispersant for concrete containing oxycarboxylic acid or a salt thereof as a main component in a total amount of 0.1 to 0.1
10 parts by weight, and naphthalenesulfonic acid formaldehyde condensate, melaminesulfonic acid formaldehyde condensate, methoxypolyethylene glycol monomethacrylate-methacrylic acid copolymer, sulfanilic acid
Phenol formaldehyde co-condensate, sulfanilic acid-bisphenols formaldehyde co-condensate, lignin sulfonate, one or more dispersants for concrete, and concrete mainly containing oxycarboxylic acid or its salt Weight ratio with dispersant
9: 1 to 1:99 concrete production method.