JP2002338325A - Hydraulic composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydraulic composition which exhibits the rapid increase in viscosity, and also has excellent exhibitability of strength. SOLUTION: The hydraulic composition contains slag and (metha)crylic ester copolymer emulsion. As the (meta)crylic ester copolymer emulsion, the polymer emulsion obtainable by the copolymerization between unsaturated carboxylic acids and an ethylenic unsaturated compound is preferable. Further, the composition can contain a hardening accelerator, and the hardening accelerator can contain aluminate and/or sulfate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a hydraulic composition for cement and concrete replacement used in the civil engineering and construction fields.
Specifically, it relates to a hydraulic composition containing slag. Preferably, excavation of underground structures such as tunnels,
Shotcrete used for repair / reinforcement of existing concrete and stabilization / covering of slopes, concrete used for rock bolt method or anchor method used for upward injection or injection into cracked ground, underwater concrete, iron Coating materials, as well as cement for extrusion molding, cement milk using a cement composition, cement mortar,
Also, the present invention relates to a hydraulic composition used in applications where cement has been conventionally used, such as applications in which the viscosity of concrete needs to be rapidly increased. In the present invention, parts and units of% are as follows.
The unit is expressed by mass unless otherwise specified.

[0002]

2. Description of the Related Art Conventionally, as additives for rapidly increasing the viscosity of cement milk, cement mortar, and concrete, formite-based minerals such as sepiolite and attapulgite (JP-A-6-264449) and ramzan gum (JP-A-7-264) have been known. JP-A-10623), psyllium seed gum (JP-A-7-206498), welan gum (JP-A-7-208097), β-1,3 glucan (JP-A-8-157249), and hydroxyethyl cellulose ( Japanese Patent Application Laid-Open No. 8-245255) is known.

On the other hand, slag is also called a latent hydraulic substance and is hardened by an alkali stimulant such as sodium hydroxide. Slag has been studied as an alternative material to cement because of the low elution amount of hexavalent chromium.

[0004]

However, slag has an extremely low hydration reaction rate, and has a problem that it is difficult to increase the viscosity even when the above-mentioned alkali stimulant is used in combination.

As a result of various studies, the present inventors have found that, when a specific substance is used in combination, a hydraulic composition containing slag shows a sharp increase in viscosity and is excellent in developing strength. Thus, the present invention has been completed.

[0006]

That is, the present invention relates to a hydraulic composition comprising slag and a (meth) acrylate copolymer emulsion, wherein the (meth) acrylate copolymer emulsion is The hydraulic composition is a polymer emulsion obtained by copolymerization of an unsaturated carboxylic acid and an ethylenically unsaturated compound,
It is the hydraulic composition containing a curing accelerator, and the curing composition contains an aluminate and / or a sulfate. And a mixture containing slag and water, and a mixture containing (meth) acrylate copolymer emulsion and water, which are mixed and used immediately before use. The method of use is to mix and use a mixture containing slag, a hardening accelerator, and water, and a mixture containing a (meth) acrylate copolymer emulsion and water immediately before use. A method of using a hydraulic composition characterized by a mixture comprising slag and water, a curing accelerator,
A method for using a hydraulic composition, characterized in that a mixture comprising a (meth) acrylate copolymer emulsion and water is mixed and used immediately before use, comprising a slag and water. And a mixture containing a curing accelerator and water and a mixture containing a (meth) acrylate copolymer emulsion and water immediately before use. It is a method of using the composition.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

Examples of the slag of the present invention include blast furnace slag by-produced from a blast furnace and steelmaking slag by-produced from a steelmaking furnace such as a converter and an electric furnace. Among these, blast furnace slag is preferred from the viewpoint of strength development, and amorphous blast furnace slag is more preferred.

The grain size of the slag of the present invention is 3 in Blaine value.
000cm is preferably not less than ² / g, more preferably at least ^{6000cm 2 / g, 9000cm 2 /} g or more is most preferred. If it is less than 3000 cm ² / g, the strength development may be reduced.

There are various (meth) acrylate copolymer emulsions used in the hydraulic composition of the present invention. However, in view of exhibiting a more excellent effect, the unsaturated carboxylic acid and the ethylenically unsaturated compound can be used. Polymer emulsions obtained by copolymerization are preferred. As the polymerization method of the polymer emulsion, unsaturated carboxylic acids and ethylenically unsaturated compound, emulsion polymerization, suspension polymerization,
Examples thereof include a method of copolymerization by a method such as solution polymerization or bulk polymerization.

[0011] The (meth) acrylate copolymer emulsion has a large thickening effect especially when used in combination with an alkali.

Examples of the unsaturated carboxylic acids include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, citraconic acid, aconitic acid and crotonic acid, and maleic anhydride and citraconic anhydride. Examples include unsaturated carboxylic anhydrides and unsaturated carboxylic half esters such as monomethyl itaconate, monobutyl itaconate, and monoethyl maleate. Of these, unsaturated carboxylic acids are preferable, and acrylic acid and / or methacrylic acid are more preferable, in that they exhibit more excellent effects.

Examples of the ethylenically unsaturated compound include ethylene, cyanovinyl monomers such as acrylonitrile and methacrylonitrile, methyl acrylate, ethyl acrylate, butyl acrylate, hexyl acrylate, cyclohexyl acrylate, octyl acrylate, hydroxyethyl acrylate, Acrylic ester monomers such as ethylhexyl acrylate and glycidyl acrylate, methacrylic ester monomers such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, hydroxyethyl methacrylate, and glycidyl methacrylate, vinyl formate, vinyl acetate, vinyl propionate, vinyl butyrate, and capron Vinyl acrylate, vinyl caprylate, vinyl laurate, vinyl stearate, octyl Vinyl and C3-18 aliphatic carboxylic acid vinyl esters such as vinyl and neodecanoic acid vinyl ester (trade name "Veoba 10" (manufactured by Shell Japan)); vinyl ether monomers such as methyl vinyl ether, ethyl vinyl ether, butyl vinyl ether, and phenyl vinyl ether; acrylamide And amide monomers such as methacrylamide, maleimide monomers such as maleimide, N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-phenylmaleimide, and N-toluylmaleimide; and halogens such as vinyl chloride and vinylidene chloride. Olefin monomer, N-vinylpyrrolidone, and ethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, propylene glycol dimethacrylate Examples include polyfunctional vinyl monomers such as polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, ethylene glycol diacrylate, polyethylene glycol diacrylate, triallyl cyanurate, triallyl isocyanurate, trimethylolpropane trimethacrylate, allyl acrylate, and allyl methacrylate. Can be Among them, acrylic ester monomers and / or methacrylic ester monomers are preferable in that they exhibit more excellent effects.

The copolymerization ratio (mass ratio) of the unsaturated carboxylic acid to the ethylenically unsaturated compound in the (meth) acrylate copolymer emulsion is such that the unsaturated carboxylic acid: ethylene Unsaturated compound = 2
0: 1 to 1:20 is preferable, and 5: 1 to 1: 5 is more preferable.

The amount of the (meth) acrylate copolymer emulsion to be used is preferably from 0.01 to 10 parts, more preferably from 0.1 to 5 parts by solid content, based on 100 parts of the slag. If the amount is less than 0.01 part, the thickening effect is reduced, and the fluidity may be increased. If the amount exceeds 10 parts, the initial strength expression may be deteriorated.

The hardening accelerator used in the hydraulic composition of the present invention includes lithium sulfate, sodium sulfate, magnesium sulfate, potassium sulfate, potassium alum, calcium sulfate, aluminum sulfate, and sulfates such as iron sulfate, and lithium carbonate. , Carbonates such as sodium carbonate and potassium carbonate, hydroxides such as lithium hydroxide, sodium hydroxide, magnesium hydroxide, aluminum hydroxide, potassium hydroxide and calcium hydroxide, calcium chloride, magnesium chloride, and chloride Chlorides such as iron; aluminates such as lithium aluminate, sodium aluminate, potassium aluminate and calcium aluminate; silicates such as lithium silicate, sodium silicate and potassium silicate; diethanolamine and triethanol Amines such as amines, formic acid Calcium salts of organic acids such as um and calcium acetate, and include colloid such as silica sol or alumina sol. One or more of these curing accelerators may be used in combination. Among these, aluminates and / or sulfates are preferable, and those using both aluminates and sulfates are preferable, since they exhibit excellent strength development and can reduce the elution amount of hexavalent chromium.

Of the aluminates, calcium aluminate is preferred in terms of the best strength development.

The calcium aluminate of the present invention is obtained by mixing a raw material containing calcia, a raw material containing alumina, etc., and performing a heat treatment such as firing in a kiln or melting in an electric furnace. And Al ₂ O ₃ as main components, and is a general term for substances having hydration activity, CaO and / or A
Part of l ₂ O ₃ is an alkali metal oxide, alkaline earth metal oxide, silicon oxide, titanium oxide, iron oxide, alkali metal halide, alkaline earth metal halide, alkali metal sulfate, alkaline earth The substance is a substance obtained by dissolving a substance substituted with a metal sulfate or the like, or a substance containing CaO and Al ₂ O ₃ as main components. The mineral form may be either crystalline or amorphous.

Among them, amorphous calcium aluminate is preferable in terms of reaction activity, and 12CaO · 7A
Amorphous calcium aluminate obtained by quenching a heat-treated product corresponding to the l ₂ O ₃ composition is more preferable.

The particle size of the calcium aluminate is preferably at least 3000 cm ² / g in Blaine value, 5000 cm ²
/ G or more is more preferable. If it is less than 3000 cm ² / g, the initial strength development may be reduced.

Among the sulfates of the present invention, calcium sulfate and / or aluminum sulfate are preferred from the viewpoint of strength development. As calcium sulfate, anhydrous gypsum, hemihydrate gypsum,
And dihydrate gypsum. Of these, anhydrous gypsum is preferred in terms of strength development.

The particle size of the sulfate is 3000 c in Blaine value.
It is preferably at least m ² / g, more preferably at least 5000 cm ² / g. If it is less than 3000 cm ² / g, the strength development may be reduced.

When aluminate and sulfate are used together as a curing accelerator, the amount of sulfate used is 100
20 to 500 parts, preferably 50 to 150 parts
Parts are more preferred. If the amount is less than 20 parts, strength developability may decrease. If the amount exceeds 500 parts, the flow may increase, the inseparability in water and the thick coating property may deteriorate, and the long-term strength developability may decrease.

The amount of the curing accelerator used is preferably 0.5 to 60 parts, more preferably 1 to 20 parts, per 100 parts of slag. When the amount is less than 0.5 part, the flow becomes large, the inseparability in water and the thick coating property are deteriorated, and there is a possibility that the strength expression is reduced.

The hydraulic composition of the present invention may contain an aggregate such as sand or gravel, an AE agent, a water reducing agent, a high-performance water reducing agent, a foaming agent, a defoaming agent,
A shrinkage reducing agent, a rust preventive, a waterproofing agent, a swelling agent, an antifreezing agent and the like may be used in combination.

The amount of water used is not particularly limited, but is preferably 25 to 200 parts, more preferably 30 to 60 parts, per 100 parts of slag. If the amount is less than 25 parts, kneading of the hydraulic composition may become difficult, and if it exceeds 200 parts, the fluidity may increase.

The method of mixing the slag and the (meth) acrylate copolymer emulsion is not particularly limited. For example, the slag and water are mixed and then mixed with the (meth) acrylate copolymer emulsion. The method of thickening is preferred.

Furthermore, when a curing accelerator is used, the method of mixing the slag, the curing accelerator, and the (meth) acrylate copolymer emulsion is not particularly limited, but, for example, (1) (a) slag, curing (B) a method of preparing a mixture of water and a mixture of water and (b) preparing two kinds of mixtures of a mixture of (meth) acrylate copolymer emulsion and water, and mixing these two kinds of mixtures to increase the viscosity;
(2) (a) a mixture of slag and water, (b) a curing accelerator,
(3) a method of preparing two kinds of mixtures of a (meth) acrylate copolymer emulsion and a mixture of water and mixing these two kinds of mixtures to increase the viscosity;
A mixture of (a) a slag and water, (b) a mixture of a curing accelerator and water, and (c) a mixture of a (meth) acrylate copolymer emulsion and water are prepared. To increase the viscosity by mixing the above mixture. In the case of (1), it is preferable to further use a curing retarder so that the mixture of the slag, the curing accelerator and the water does not cure immediately. In the case of (2) or (3), when a curing accelerator composed of only an aluminate or a combination of an aluminate and a sulfate is used, there is a possibility that the composition is cured within one hour after being mixed with water. Therefore, it is preferable to use a curing retarder in combination.

As the curing retarder, citric acid, tartaric acid,
Gluconic acid and oxycarboxylic acids such as malic acid, oxycarboxylic acid salts thereof, boric acid, tripolyphosphate,
And pyrophosphates. One or more of these curing retarders may be used in combination. Of these, oxycarboxylic acids and / or oxycarboxylates are preferred, and citric acid and / or sodium citrate are more preferred, in that they have a large delay effect.

The amount of the curing retarder to be used is preferably 0.01 to 10 parts, more preferably 0.05 to 5 parts, per 100 parts of slag. If it is less than 0.01 part, the retarding effect may be small, and if it exceeds 10 parts, the strength expression may be reduced.

In the actual application, when used as a spraying material, a mixture of slag and water and a (meth) acrylate copolymer emulsion are separately fed under pressure, and are mixed and mixed at the tip of the discharge port. It is preferable to carry out the construction while performing.

As the method of merging and mixing, a method using a mixing tube such as a Y-shaped tube, a method using a double tube, and an inlet piece for making the hydraulic composition liquid and merging and mixing like a shower are used. Method and the like. Further, there is also a method of setting a spiral mixer in the tube after the combined mixing and further mixing.

[0033]

EXAMPLES Hereinafter, the present invention will be further described with reference to experimental examples of the present invention, but the present invention is not limited thereto.

Experimental Example 1 100 parts of slag A and 40 parts of water were kneaded with a mixer to prepare Agent A. Next, a B agent was prepared by mixing 100 parts of slag with a solid content of (meth) acrylate copolymer emulsion α in an amount shown in Table 1 and 5 parts of water. The A agent and the B agent were continuously charged into the mixer and kneaded for 30 seconds. With respect to the kneaded material, fluidity, inseparability in water, thick coating property, compressive strength, and elution amount of hexavalent chromium were measured. The water inseparability was evaluated based on Table 1, and the thick coating property was evaluated based on Table 2. The results are shown in Table 3.

<Material used> Slag A: Blast furnace slag crushed product, amorphous, Blaine value 10
500 cm ² / g, commercial product Curing accelerator a: aluminate (calcium aluminate,
12CaO · 7Al ₂ O ₃ obtained by quenching the corresponding heat-treated product to the composition, amorphous, Blaine 6000cm ² / g) 1
00 parts and sulfate (anhydrite, Blaine value 5400cm ²
/ G) a mixture consisting of 100 parts (meth) acrylate copolymer emulsion α:
Solid content concentration 30%, ethyl acrylate / methacrylic acid copolymer emulsion, polymer composition: ethyl acrylate: methacrylic acid = 45: 55 (mass ratio)

<Measurement Method> Fluidity: The kneaded material was placed in a cylinder having an inner diameter of 80 mm and a height of 80 mm, and the spread after pulling out the cylinder was measured after 2 minutes. Underwater non-separability: It was carried out in accordance with the underwater separability test in the appendix of the Japan Society of Civil Engineers guide for design and construction of underwater non-separable concrete. The evaluation criteria are shown in Table 1.

[0037]

[Table 1]

Thick coatability: The thick coatability test was carried out in accordance with the thick coatability test specified by the Japan Highway Public Corporation's section repair material standard. The evaluation criteria are shown in Table 2.

[0039]

[Table 2]

Compressive strength: Compressive strength was measured according to JIS R 5201, and the compressive strength at a given age was measured.

Hexavalent chromium elution amount: Measured in accordance with the Environment Agency Notification No. 46. Measurement material age is 1 day.

[0042]

[Table 3]

Experimental Example 2 An A agent was prepared by kneading 100 parts of slag A, 40 parts of water, 3 parts of a curing accelerator a, and 2 parts of a curing retarder with 100 parts of slag A using a mixer. Next, a B agent was prepared by mixing 1 part (solid) of the (meth) acrylate copolymer emulsion α and 5 parts of water with respect to 100 parts of the slag. The A agent and the B agent were continuously charged into the mixer and kneaded for 30 seconds. With respect to the kneaded material, fluidity, inseparability in water, thick coating property, compressive strength, and elution amount of hexavalent chromium were measured. The results are shown in Table 4.

<Materials used> Curing retarder: oxycarboxylic acid, citric acid, commercial product

[0045]

[Table 4]

Experimental Example 3 A composition was prepared by kneading 100 parts of slag A and 40 parts of water with a mixer. Next, a B agent was prepared by mixing 3 parts of a curing accelerator a, 100 parts of a (meth) acrylate copolymer emulsion α of 1 part in solid content, and 5 parts of water with 100 parts of slag A. Continue to add the A agent and B agent to the mixer,
Kneaded for seconds. For kneaded materials, fluidity, inseparability in water,
Thick coating property, compressive strength, and hexavalent chromium elution amount were measured. The results are shown in Table 5.

[0047]

[Table 5]

Experimental Example 4 A part was prepared by kneading 100 parts of slag B and 40 parts of water with a mixer. Next, 3 parts of the hardening accelerator and 5 parts of water shown in Table 6 were mixed with 100 parts of slag B to prepare a B agent.
Further, 1 part of (meth) acrylic acid ester copolymer emulsion α and 100 parts of water
The parts were mixed to prepare a C agent. The A agent, the B agent, and the C agent were continuously charged into the mixer and kneaded for 30 seconds. The kneaded material was measured for fluidity, inseparability in water, thick coatability, and compressive strength. The results are shown in Table 6. For comparison, a similar experiment was performed using a non- (meth) acrylate copolymer emulsion having no alkali thickening instead of the (meth) acrylate copolymer emulsion.

<Materials Used> Slag B: Blast furnace slag crushed product, amorphous, Blaine value 95
00 cm ² / g, commercial product Curing accelerator b: sulfate, aluminum sulfate, commercial product Curing accelerator c: carbonate, sodium carbonate, commercial product Curing accelerator d: hydroxide, calcium hydroxide, commercial product Acceleration Agent e: aluminate, sodium aluminate,
Commercially available curing accelerator f: colloid, silica sol, commercially available curing accelerator g: aluminate, calcium aluminate,
A heat-treated product corresponding to the composition of 12CaO · 7Al ₂ O ₃ quenched, amorphous, Blaine value 6000 cm ² / g) Non- (meth) acrylic acid ester copolymer emulsion:
Solid content concentration: 30%, styrene / 2-ethylhexyl acrylate copolymer emulsion, polymer composition: styrene: 2-ethylhexyl acrylate = 45:
55 (mass ratio)

[0050]

[Table 6]

Experimental Example 5 A part A was prepared by kneading 100 parts of slag A and 40 parts of water.
Hardening accelerator a in the amount shown in Table 7 with respect to 100 parts of slag A
And 5 parts of water are kneaded to prepare a B agent, and 100 parts of slag A is mixed with 1 part (meth) acrylate copolymer emulsion β of solid content and 5 parts of water to prepare a C agent. ,
The procedure was performed in the same manner as in Experimental Example 4 except that the fluidity, inseparability in water, thick coating property, compressive strength, and hexavalent chromium elution amount were measured. The results are shown in Table 7.

<Materials> (Meth) acrylic ester copolymer emulsion β: solid content concentration 30%, ethyl acrylate / acrylic acid copolymer emulsion (polymer composition is ethyl acrylate: methacrylic acid)
= 45: 55 (mass ratio)) and 30 parts of ethylene / vinyl acetate copolymer emulsion (polymer composition: ethylene: vinyl acetate = 18: 82 (mass ratio))

[0053]

[Table 7]

Experimental Example 6 A part A was prepared by kneading 100 parts of slag B and 40 parts of water.
3 parts of the hardening accelerator a and 5 parts of water are kneaded with 100 parts of slag B to prepare a B agent, and the amount of the (meth) acrylate copolymer emulsion in the amount shown in Table 8 in solid content with respect to 100 parts of slag B Performed in the same manner as in Experimental Example 4 except that β part was mixed with 5 parts of water to prepare a C agent, and the fluidity, inseparability in water, thick coating property, compressive strength, and hexavalent chromium elution amount were measured. Was. The results are shown in Table 8.

[0055]

[Table 8]

Experimental Example 7 Cement was used without using slag. 100 parts of cement and 40 parts of water are kneaded to prepare an A agent, 100 parts of cement are kneaded with 3 parts of a hardening accelerator a and 5 parts of water to prepare an B agent, and 100 parts of cement are mixed with 100 parts of cement. With 1 part of (meth) acrylate copolymer emulsion β and water 5
The same procedure as in Experimental Example 4 was carried out except that the C agent was prepared by mixing the parts, and the elution amount of hexavalent chromium was measured. The results are shown in Table 9.

<Materials> Cement: ordinary Portland cement, commercially available

[0058]

[Table 9]

[0059]

The following characteristics can be obtained by using the hydraulic composition of the present invention. 1. The viscosity can be rapidly increased. 2. Good inseparability and thick coating property in water. 3. Strength developability is improved. 4. There is no risk of eluting the amount of hexavalent chromium.

Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat II (reference) C04B 22:08 C04B 22:14 A 22:14) F term (reference) 4G012 PB05 PB10 PB31 4J100 AA02Q AC03Q AC04Q AE02Q AE03Q AE09Q AG02Q AG03Q AG04Q AJ01P AJ02P AJ08P AJ09P AK31P AK32P AL03Q AL04Q AL08Q AL09Q AL10Q AL36P AL44P AL62Q AL63Q AL66Q AL75Q AM02Q AM15Q AM43Q AM45Q AM48Q AQ08Q AQ19Q BA08Q BC04EA BC43CA04

Claims (8)

[Claims] 1. A hydraulic composition comprising a slag and a (meth) acrylate copolymer emulsion. 2. The hydraulic composition according to claim 1, wherein the (meth) acrylic acid ester copolymer emulsion is a polymer emulsion obtained by copolymerizing an unsaturated carboxylic acid and an ethylenically unsaturated compound. 3. The hydraulic composition according to claim 1, further comprising a curing accelerator. 4. The hydraulic composition according to claim 3, wherein the curing accelerator contains an aluminate and / or a sulfate. 5. A mixture comprising slag and water,
A method for using a hydraulic composition, wherein a mixture comprising a (meth) acrylate copolymer emulsion and water is mixed and used immediately before use. 6. A mixture comprising a slag, a curing accelerator and water, and a mixture comprising a (meth) acrylate copolymer emulsion and water immediately before use. Use of the hydraulic composition as a feature. 7. A method comprising mixing a mixture containing slag and water, a curing accelerator, a (meth) acrylate copolymer emulsion, and a mixture containing water immediately before use. Use of the hydraulic composition as a feature. 8. A mixture containing slag and water, a mixture containing a curing accelerator and water, and a mixture containing a (meth) acrylate copolymer emulsion and water immediately before use. A method for using a hydraulic composition, which is used by mixing.