Additive for hydraulic composition

Abstract

To provide an additive for a hydraulic composition that improves polymer dispersibility in the hydraulic composition, suppresses the flow of the hydraulic composition, and prevents laitance formation and shape deformation.SOLUTION: An additive for a hydraulic composition comprises: (A) a clay mineral; and (B) one or more selected from acrylic acid-based polymers and cellulose-based polymers.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to an additive for hydraulic compositions, a method for producing an additive for hydraulic compositions, a method for producing a hydraulic composition, and a spraying method.

Background Art

[0002] In order to prevent the collapse of exposed natural ground such as tunnel excavation, a spraying method using quick-setting concrete or quick-setting mortar in which a quick-setting agent is blended into concrete is performed. In this method, usually, sprayed concrete is prepared in a metering and mixing plant for cement, aggregate, and water installed at the excavation work site, and it is transported by an agitator truck and transferred to a spraying machine. Then, the sprayed concrete and the quick-setting agent are joined and mixed by a line that pneumatically transports the sprayed concrete to the discharge port by a pump of the spraying machine and a line that pneumatically transports the quick-setting agent from the other side through a joining pipe provided in the middle thereof, and it is a method of spraying the quick-setting sprayed concrete onto the natural ground surface until it reaches a predetermined thickness.

[0003] Patent Document 1 discloses an additive for hydraulic compositions containing a polymer having a structural unit formed from acrylic acid and / or its salt having a predetermined mass average molecular weight and a polymer having a structural unit from acrylic acid and / or its salt having a predetermined mass average molecular weight. Patent Document 2 discloses a cement material containing a predetermined alkyl-modified vinyl alcohol-based polymer. Patent Document 3 discloses a liquid quick-setting agent containing aluminum sulfate, a water-soluble cellulose ether, and water, in which insoluble particles are dispersed in the liquid at -10 to 40°C and 90% or more of the liquid is suspended by volume ratio. Patent Document 4 discloses an additive for a sprayed hydraulic composition containing (A) a clay mineral having a swelling degree of 15 mL / 2 g or more and 50 mL / 2 g or less and (B) one or more quick-setting agents selected from a cement mineral-based quick-setting agent and an aluminum-based quick-setting agent. Patent Document 5 discloses an adhesion reducer for a pipe for a sprayable hydraulic composition, which contains (A) a polymer having a weight average molecular weight of 20,000 or more and 6,500,000 or less, containing a monomer selected from acrylic acid or its salt, an acrylic acid ester, methacrylic acid or its salt, a methacrylic acid ester, and acrylamide, and (B) a quick-setting agent.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Summary of the Invention

Problems to be Solved by the Invention

[0005] When polymers such as acrylic polymers and cellulose polymers do not dissolve well in water and form lumps, the dispersibility in the hydraulic composition decreases, and it may be difficult to uniformly act these polymers on the hydraulic composition. The present invention provides an additive for a hydraulic composition that improves the dispersibility of polymers in a hydraulic composition, suppresses the flow of the hydraulic composition, and suppresses the generation and shape change of lumps, a method for producing the additive for a hydraulic composition, a method for producing a hydraulic composition, and a spraying method.

Means for Solving the Problems

[0006] The present invention relates to an additive for a hydraulic composition, which contains (A) a clay mineral [hereinafter referred to as component (A)] and at least one selected from (B) an acrylic polymer and a cellulose polymer [hereinafter referred to as component (B)].

[0007] The present invention also relates to a method for producing an additive for a hydraulic composition, which involves mixing component (A) and component (B).

[0008] The present invention also relates to a method for producing a hydraulic composition, which involves mixing the additive for a hydraulic composition of the present invention, hydraulic powder, and water to obtain a hydraulic composition.

[0009] The present invention also relates to a method for producing a hydraulic composition, which involves mixing component (A) and component (B) to obtain an additive for a hydraulic composition, and mixing the additive for a hydraulic composition, hydraulic powder, and water to obtain a hydraulic composition.

[0010] The present invention also relates to a spraying method, which involves mixing the additive for a hydraulic composition of the present invention, hydraulic powder, and water to obtain a hydraulic composition, and spraying the hydraulic composition onto a target surface.

[0011] The present invention also relates to a spraying method, which involves mixing component (A) and component (B) to obtain an additive for a hydraulic composition, mixing the additive for a hydraulic composition, hydraulic powder, and water to obtain a hydraulic composition, and spraying the hydraulic composition onto a target surface.

Advantages of the Invention

[0012] According to the present invention, there are provided an additive for a hydraulic composition that improves the dispersibility of polymers in a hydraulic composition, suppresses the flow of the hydraulic composition, and suppresses the generation and shape change of noro, a method for producing an additive for a hydraulic composition, a method for producing a hydraulic composition, and a spraying method.

Embodiments for Carrying Out the Invention

[0013] The present invention relates to an additive for a hydraulic composition, a method for producing the additive for a hydraulic composition, a hydraulic composition, a method for producing the hydraulic composition, and a spraying method. In particular, the present invention relates to an additive for a hydraulic composition used when spraying quick-setting concrete or quick-setting mortar on tunnels such as roads, railways, and water conduits, and on slopes formed by excavation of natural ground, embankment, etc., a method for producing the additive for a hydraulic composition, a hydraulic composition, a method for producing the hydraulic composition, and a spraying method. Note that the hydraulic composition referred to in the present invention is a general term for cement mortar and cement concrete.

[0014] Although the mechanism by which the additive for a hydraulic composition and the hydraulic composition of the present invention improve the dispersibility of the polymer in the hydraulic composition, suppress the flow of the hydraulic composition, and suppress the generation and shape change of noro is not clear, it is presumed as follows. It is presumed that when the acrylic polymer or cellulose polymer of component (B) comes into contact with water, the presence of the clay mineral which is component (A) in the vicinity of component (B) reduces the adhesion due to the direct contact of component (B) with each other. Also, it is presumed that the mass formed by component (A) is broken by the water absorption and swelling of component (B). Due to these effects, it is presumed that the additive for a hydraulic composition containing component (A) and component (B) suppresses the formation of a mass (so-called lump) containing component (A) and component (B) that does not dissolve in water when mixed with water, and can disperse component (B) more uniformly in the hydraulic composition. As a result, for example, when mixed with a hydraulic composition, it is presumed that it can quickly exhibit the thickening property of the hydraulic composition and exhibit a high shape retention property and noro suppression effect in the hydraulic composition. Note that the additive for a hydraulic composition, the method for producing the additive for a hydraulic composition, the hydraulic composition, the method for producing the hydraulic composition, and the spraying method of the present invention are not limited to the above action mechanism at all. Also, in this specification, noro refers to a mixture containing powder separated from a hydraulic composition and water, that is, a paste component. Noro has a large amount of moisture, and if the amount of water locally increases due to the generation of noro, the strength of the hydraulic composition may decrease.

[0015] <Additive for hydraulic composition> The additive for a hydraulic composition of the present invention contains (A) a clay mineral [which is the component (A)] and one or more selected from an acrylic acid polymer and a cellulose polymer [hereinafter referred to as the component (B)].

[0016] <Component (A)> (A) The component is a clay mineral. One or more kinds of the component (A) can be used. From the viewpoint of suppressing the generation of slime and shape change of the hydraulic composition, a clay mineral having a swelling degree of 4 mL / 2 g or more and 100 mL / 2 g or less, and more preferably 4 mL / 2 g or more and 60 mL / 2 g or less is preferable.

[0017] (A) The clay mineral of the component preferably has a swelling degree of 4 mL / 2 g or more, more preferably 10 mL / 2 g or more, still more preferably 15 mL / 2 g or more, even more preferably 20 mL / 2 g or more, and preferably 100 mL / 2 g or less, more preferably 80 mL / 2 g or less, still more preferably 60 mL / 2 g or less, from the viewpoint of suppressing the generation of slime and shape change of the hydraulic composition. This swelling degree is measured according to the swelling test method for bentonite (powdered) of JBAS104:77 of the Japan Bentonite Industry Association. That is, 2.0 g of a sample adjusted to 8.0% by mass of moisture is added to a 100 mL stoppered graduated cylinder containing 100 mL of distilled water in about 10 portions. At this time, the next addition is made after the previous additive has deposited on the bottom of the graduated cylinder. When left for 24 hours, the apparent volume of the sample mass at the bottom of the graduated cylinder that has swelled is read from the scale of the graduated cylinder and expressed as the swelling degree (mL / 2 g).

[0018] Component (A) preferably contains 20% by mass or more, more preferably 30% by mass or more, still more preferably 35% by mass or more, even more preferably 38% by mass or more, even more preferably 40% by mass or more of smectite when dried, from the viewpoint of suppressing the generation and shape change of noro in the hydraulic composition. From the viewpoint of preventing moisture absorption of the additive for the hydraulic composition, a clay mineral preferably contains 100% by mass or less, more preferably 80% by mass or less, still more preferably 60% by mass or less. The smectite content of component (A) when dried is the smectite content calculated based on the adsorption amount of the following methylene blue in component (A) dried at 105 °C for 1 hour in a warm air dryer.

[0019] <Measurement method of smectite content of component (A)> (1) Measurement of methylene blue adsorption amount The methylene blue adsorption amount of component (A) is measured by the following method in accordance with Japanese Industrial Standard (JIS Z 2451:2019). <Reagent> 10 mmol / L aqueous solution of methylene blue (molecular weight 374) 0.2% by mass aqueous solution of sodium pyrophosphate (Na4P2O7) <Operation method> Put about 0.4 g of component (A) into a 100 mL screw tube, and add 40 g of a 0.2% by mass aqueous solution of sodium pyrophosphate thereto. After dispersing this mixture in an ultrasonic cleaner (ASUCLEANER, ASU-3, AS ONE Corporation) for 30 minutes, it is heated with warm water at 80 °C for 30 minutes. While stirring the dispersed mixture with a magnetic stirrer, a 10 mmol / L aqueous methylene blue solution is dropped. Each time a predetermined amount is dropped, a part of the mixture is sucked up from the supernatant using a glass Pasteur pipette and dropped onto filter paper. The supernatant is dropped so that a spot with a diameter of about 10 mm is formed on the filter paper. This operation is repeated until a halo is confirmed around the spot. When a halo is confirmed, the end point of the titration is taken when the width of the halo exceeds 2 mm. The calculation of the methylene blue adsorption amount (mmol) is to convert the product of the titration volume (L) and the methylene blue aqueous solution concentration (10 mmol / L) per 100 g of component (A). (2) Calculation of smectite content The calculation of the smectite content is carried out with reference to "A proposed method for the determination of small amounts of smectites in clay mineral mixtures, Proceedings of British Ceramics Society 28 137 - 145, 1979" and "Evaluation of the montmorillonite content of bentonite considering the measurement accuracy of the methylene blue adsorption test, Journal of the Japan Society of Civil Engineers, Ser. C (Geotechnical Engineering), Vol. 76, No. 1, 26 - 39, 2020". Specifically, 140 mmol / 100 g is adopted as the saturated methylene blue adsorption amount of smectite. From the methylene blue adsorption amounts of various measured clay minerals, the saturated adsorption amount is subtracted and then multiplied by 100 to calculate the smectite content of various clay minerals.

[0020] Examples of the clay mineral of component (A) include cation - exchangeable layered silicates. Examples of such clay minerals include one or more clay minerals selected from smectite and bentonite. Smectite is a group of cation - exchangeable layered silicates belonging to clay minerals. As natural products, in addition to montmorillonite, which is well - known as the main component of bentonite, there are beidellite, hectorite, saponite, nontronite, etc. As synthetic products, there are swelling fluorine - based micas, etc. Among these, as the clay mineral contained in the additive for the hydraulic composition of the present invention, from the viewpoint of suppressing the generation of noro and shape change of the hydraulic composition, clay minerals selected from bentonite, saponite, hectorite, and montmorillonite are preferable, clay minerals selected from bentonite and montmorillonite are more preferable, and bentonite is even more preferable. The content of the clay mineral selected from bentonite, saponite, hectorite, and montmorillonite is preferably 60% by mass or more, more preferably 100% by mass in the (A) component, and it is even more preferable that the content of bentonite is 100% by mass.

[0021] (A) From the viewpoint of suppressing the generation and shape change of noro in the hydraulic composition, the average particle diameter of the component is preferably 0.5 μm or more, more preferably 2 μm or more, still more preferably 5 μm or more, and from the viewpoint of noro suppression, it is preferably 100 μm or less, more preferably 80 μm or less, still more preferably 60 μm or less. (A) The average particle diameter of the clay mineral of the component is a value measured in an ethanol solvent with a laser diffraction / scattering particle size distribution measuring device (LA-920).

[0022] <(B) component> (B) The component is one or more selected from (B) acrylic acid-based polymers and cellulose-based polymers.

[0023] <Polyacrylic acid-based polymer> (B) As the acrylic acid-based polymer of the component, a polymer containing structural units derived from one or more monomers selected from acrylic acid or its salts, acrylic acid esters, methacrylic acid or its salts, methacrylic acid esters, and acrylamide [hereinafter referred to as monomer (B1)] is preferable, and a polymer having a weight average molecular weight of 20,000 or more and 6.5 million or less is more preferable. (B) The acrylic acid-based polymer of the component may be a polymer containing structural units derived from monomer (B1).

[0024] Examples of the salts of acrylic acid or its salts and methacrylic acid or its salts include sodium salts, potassium salts, ammonium salts, aminium salts, and calcium salts. Examples of the acrylic ester include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, hexyl acrylate, octyl acrylate, hydroxyethyl acrylate, 2-ethylhexyl acrylate, and glycidyl acrylate. Examples of the methacrylic ester include methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, hexyl methacrylate, octyl methacrylate, hydroxyethyl methacrylate, 2-ethylhexyl methacrylate, and glycidyl methacrylate.

[0025] The monomer (B1) is preferably one or more monomers selected from acrylic acid or its salt, methacrylic acid or its salt, and acrylamide, more preferably one or two monomers selected from acrylic acid or its salt and acrylamide, and still more preferably a monomer of acrylic acid or its salt.

[0026] The acrylic polymer of component (B) may contain a structural unit derived from a monomer other than the monomer (B1) [hereinafter referred to as monomer (B2)]. Examples of the monomer (B2) include unsaturated carboxylic acids such as itaconic acid, maleic acid, fumaric acid, citraconic acid, aconitic acid, and crotonic acid; unsaturated carboxylic acid anhydrides such as maleic anhydride and citraconic anhydride; unsaturated carboxylic acid half-esters such as monomethyl itaconate, monobutyl itaconate, and monoethyl maleate; unsaturated sulfonic acids such as vinylsulfonic acid, methallylsulfonic acid, and 2-(meth)acrylamido-2-methylpropanesulfonic acid; unsaturated phosphoric acids such as 2-((meth)acryloyloxy)ethyl phosphate and bis[2-((meth)acryloyloxy)ethyl] hydrogen phosphate; unsaturated phenols such as vinylphenol; cyanovinyls such as ethylene, acrylonitrile, and methacrylonitrile; vinyl esters of aliphatic carboxylic acids having 3 to 18 carbon atoms such as vinyl formate, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl stearate, vinyl octylate, and vinyl neodecanoate; vinyl ether monomers such as methyl vinyl ether, ethyl vinyl ether, butyl vinyl ether, and phenyl vinyl ether; polyfunctional vinyl monomers such as allyl methacrylate; unsaturated hydrocarbons such as styrene and butadiene; and unsaturated amide compounds such as methacrylamide, N-isopropylacrylamide, N-isopropylmethacrylamide, and N-vinylpyrrolidone.

[0027] In the total constituent units constituting the acrylic polymer of component (B), the proportion of the constituent units derived from monomer (B1) is preferably 60 mol% or more, more preferably 70 mol% or more, still more preferably 80 mol% or more, even more preferably 90 mol% or more, and preferably 100 mol% or less, and may be 100 mol%. This proportion may be the proportion of monomer (B1) in all the monomers used in the synthesis of component (B).

[0028] From the perspective of suppressing the generation of noro and shape changes in the hydraulic composition, the acrylic polymer of component (B) is preferably at least one selected from polyacrylic acid and its salts, polymethacrylic acid and its salts, and polyacrylamide, more preferably at least one selected from polyacrylic acid and its salts, and polyacrylamide, and even more preferably polyacrylic acid or its salt.

[0029] From the perspective of suppressing the generation of noro and shape changes in the hydraulic composition, the viscosity at 25 °C of an aqueous solution or dispersion of the acrylic polymer of component (B) at a concentration of 1% by mass is preferably 3 mPa·s or more, more preferably 10 mPa·s or more, even more preferably 20 mPa·s or more, and from the same perspective, preferably 5,000 mPa·s or less, more preferably 1,500 mPa·s or less, even more preferably 100 mPa·s or less.

[0030] From the perspective of suppressing the generation of noro and shape changes in the hydraulic composition, the weight average molecular weight of the acrylic polymer of component (B) is preferably 0.3×10⁴ or more, more preferably 0.6×10⁴ or more, even more preferably 1×10⁴ or more, even more preferably 2×10⁴ or more, and from the same perspective, preferably 6.5×10⁶ or less, more preferably 2×10⁶ or less, even more preferably 1×10⁶ or less, even more preferably 5×10⁵ or less, even more preferably 2×10⁵ or less.

[0031] The weight average molecular weight of the acrylic polymer of component (B) can be determined by gel permeation chromatography under the following conditions, using a mixed solvent of acetonitrile and water (phosphate buffer) as the developing solvent and polyethylene glycol as the standard substance. Column: GMPWXL - GMPWXL (anion) manufactured by Tosoh Corporation Detector: Differential refractive index detector Eluent: 0.2 M phosphate buffer / acetonitrile = 9 / 1 Standard: Polyethylene glycol conversion (monodisperse polyethylene glycol with known molecular weight, molecular weights: 21,000, 44,200, 101,000, 185,000, 580,000, 977,000) Conditions: Column temperature: 40 °C, Flow rate: 0.5 mL / min, Concentration: 2 mg / mL

[0032] <Cellulosic polymer> The cellulosic polymer of component (B) includes modified celluloses, particularly carboxyalkyl, alkyl or hydroxyalkyl modified celluloses typified by carboxymethyl cellulose, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxyethyl methyl cellulose, and hydroxypropyl methyl cellulose.

[0033] From the viewpoint of suppressing the occurrence of slump and shape change of the hydraulic composition, the viscosity at 25 °C of an aqueous solution or dispersion of the cellulosic polymer of component (B) at a concentration of 1% by mass is preferably 10 mPa·s or more, more preferably 30 mPa·s or more, still more preferably 60 mPa·s or more, even more preferably 300 mPa·s or more, even more preferably 2,000 mPa·s or more, and from the same viewpoint, preferably 7,000 mPa·s or less, more preferably 6,000 mPa·s or less, still more preferably 5,000 mPa·s or less. The above viscosity is measured at a rotational speed of 60 rpm using a B-type viscometer (VISCOMETER, MODEL BM, manufactured by Tokyo Keiki Co., Ltd. (former Tokimec Co., Ltd.), rotor No. 2).

[0034] From the viewpoint of suppressing the occurrence of slump and shape change of the hydraulic composition, the weight average molecular weight of the cellulosic polymer of component (B) is preferably 10,000 or more, more preferably 100,000 or more, still more preferably 400,000 or more, even more preferably 800,000 or more, even more preferably 1,500,000 or more, and preferably 20,000,000 or less, more preferably 10,000,000 or less, still more preferably 6,000,000 or less. The above weight average molecular weight is measured by gel permeation chromatography based on the following measurement conditions.

[0035] <Method for measuring weight average molecular weight> (B) The weight average molecular weight of the component can be measured by GPC (gel permeation chromatography), and the weight average molecular weight (Mw) can be determined using a conversion standard substance. The GPC measurement conditions are shown below. · Apparatus: HLC-8320 GPC (manufactured by Tosoh Corporation, detector integrated type) · Column: manufactured by Tosoh Corporation, product name: TSK-GEL guardcolumn PWXL manufactured by Tosoh Corporation, product name: TSK-GEL GMPWXL manufactured by Tosoh Corporation, product name: TSK-GEL GMPWXL · Mobile phase: 0.2 mol / L phosphate buffer (aqueous solution of potassium dihydrogen phosphate and disodium hydrogen phosphate, pH = 7) / acetonitrile = 90 / 10 (volume ratio) · Detector: differential refractive index detector · Column temperature: 40 °C · Flow rate: 0.5 mL / min · Conversion standard substance: polyethylene oxide [manufactured by Tosoh Corporation] · Sample: Ultra-pure water is added to an aqueous polymer solution containing 5 mg of solid content, and the total liquid volume is adjusted to 10 mL. 100 μL is taken from this prepared solution and injected into the column.

[0036] (B) The cellulose-based polymer of the component is preferably at least one selected from carboxymethyl cellulose and its salts, hydroxyethyl cellulose, and hydroxypropyl methylcellulose from the viewpoint of suppressing the generation of noro and shape change of the hydraulic composition, and carboxymethyl cellulose or its salt is more preferable. Examples of the salt of carboxymethyl cellulose include alkali metal salts such as sodium salt and potassium salt, and ammonium salts. From the viewpoint of easy availability, etc., the salt of carboxymethyl cellulose is preferably an alkali metal salt of carboxymethyl cellulose, and the sodium salt of carboxymethyl cellulose (sodium carboxymethyl cellulose) is more preferable.

[0037] From the perspective of suppressing the generation of slump and shape change of the hydraulic composition, the degree of etherification of the carboxymethyl cellulose or its salt in component (B) is preferably 0.5 or more, more preferably 0.55 or more, still more preferably 0.6 or more, and from the same perspective, preferably 1.5 or less, more preferably 1.3 or less, still more preferably 1.0 or less. The degree of etherification of the carboxymethyl cellulose or its salt in component (B) refers to the degree of substitution of carboxymethyl groups per glucose unit of the carboxymethyl cellulose or its salt in component (B). When component (B) is sodium carboxymethyl cellulose, its degree of etherification is measured by the following method according to, for example, the CMC Industrial Association analysis method (ashing method). When component (B) is a salt other than sodium carboxymethyl cellulose of carboxymethyl cellulose, the degree of etherification of component (B) can also be measured by the same method.

[0038] <Measurement of the Degree of Etherification of Sodium Carboxymethyl Cellulose> Precisely weigh 1 g of sodium carboxymethyl cellulose, put it in a magnetic crucible, and ash it at 600 °C. Titrate the sodium oxide generated by ashing with N / 10 sulfuric acid using phenolphthalein as an indicator, and substitute the titration volume Y mL per 1 g of sodium carboxymethyl cellulose into the following formula for calculation, and the obtained degree of etherification can be shown. Degree of etherification = (162 × Y) / (10,000 - 80 × Y)

[0039] From the perspective of suppressing the generation of slump and shape change of the hydraulic composition, the carboxymethyl cellulose or its salt in component (B) is preferably at least one selected from the group consisting of carboxymethyl cellulose and sodium carboxymethyl cellulose, and sodium carboxymethyl cellulose is more preferred. Examples of commercially available sodium carboxymethyl cellulose used as component (B) include the CMC Daicel series manufactured by Daicel Corporation, the Sunrose series manufactured by Nippon Paper Industries Co., Ltd., and the Serogen series of Daiichi Kogyo Seiyaku Co., Ltd.

[0040] Component (B) is preferably at least one selected from carboxymethyl cellulose and its salts, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, polyacrylic acid and its salts, polymethacrylic acid and its salts, and polyacrylamide. More preferably, it is at least one selected from polyacrylic acid, carboxymethyl cellulose and their salts. Even more preferably, it is carboxymethyl cellulose or its salt, from the viewpoint of suppressing the generation of noro and shape change of the hydraulic composition.

[0041] Component (B) may be at least one solid selected from acrylic polymers and cellulose polymers, and further may be a powdery polymer. In the present invention, "powdery" means a solid state, and typically refers to powders such as fine powder, powder, fine granule, and granule. The powdery component (B) may be a polymer having the following average particle size. When component (B) is solid, and further powdery, from the viewpoint of suppressing the generation of noro and shape change of the hydraulic composition, the average particle size of component (B) is preferably 0.5 μm or more, more preferably 1.0 μm or more, still more preferably 5.0 μm or more. And from the same viewpoint, it is preferably 500 μm or less, more preferably 300 μm or less, still more preferably 150 μm or less. The average particle size of component (B) is measured by the following method.

[0042] <Measurement method of average particle size of component (B)> Weigh a solid, and further powdery component (B) on a slide glass and photograph it with a digital microscope (DSX1000, manufactured by OLYMPUS CORPORATION, 180 times magnification). Measure the diameters of 100 powder particles of component (B) from the obtained image, and calculate the average particle size from the arithmetic mean of those values. In addition, when measuring the diameter of the powder particles of component (B), if the powder particles are circular, the diameter is used. If the powder particles of component (B) are elliptical, amorphous, or have a high aspect ratio, the longest part is taken as the diameter. Also, when the average particle size of component (B) is less than 30 μm, the image is photographed with the magnification of the digital microscope set to 600 times, the diameter of the powder particles of component (B) is measured, and the average particle size of component (B) is calculated.

[0043] <Composition, etc.> The additive for hydraulic composition of the present invention contains component (A) preferably at 10% by mass or more, more preferably at 30% by mass or more, still more preferably at 60% by mass or more, even more preferably at 90% by mass or more, even more preferably at 95% by mass or more, even more preferably at 99% by mass or more, from the viewpoint of the storage stability of the additive for hydraulic composition, and preferably at 99.9% by mass or less, more preferably at 99.7% by mass or less, still more preferably at 99% by mass or less, from the viewpoint of suppressing the generation of slump and shape change of the hydraulic composition. Also, the preferable content of the above component (A) may be the preferable content of component (A) in the additive for hydraulic composition not containing component (C) which will be described in detail later. Further, when the additive for hydraulic composition contains component (C), the preferable content of the above component (A) may be the preferable content of component (A) in the additive for hydraulic composition excluding component (C).

[0044] The additive for hydraulic composition of the present invention contains component (B) preferably at 0.05% by mass or more, more preferably at 0.1% by mass or more, still more preferably at 0.2% by mass or more, from the viewpoint of suppressing the generation of slump and shape change of the hydraulic composition, and preferably at 80% by mass or less, more preferably at 50% by mass or less, still more preferably at 20% by mass or less, even more preferably at 10% by mass or less, from the viewpoint of the storage stability of the additive for hydraulic composition. The preferable content of the above component (B) may be the preferable content of component (B) in the additive for hydraulic composition not containing component (C) which will be described in detail later. Further, when the additive for hydraulic composition contains component (C), the preferable content of the above component (B) may be the preferable content of component (B) in the additive for hydraulic composition excluding component (C).

[0045] From the perspective of suppressing the generation of slime and shape change of the hydraulic composition, the total content of component (A) and component (B) in the additive for hydraulic composition of the present invention is preferably 60% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more, and, for example, 100% by mass or less, further 98% by mass or less, still further 95% by mass or less. The additive for hydraulic composition of the present invention may be a composition containing 100% by mass in total of component (A) and component (B), that is, an additive for hydraulic composition composed of component (A) and component (B). The preferable range of the total content of the above component (A) and component (B) may be the preferable range of the total content of component (A) and component (B) in the additive for hydraulic composition not containing component (C) which will be described in detail later. Further, when the additive for hydraulic composition contains component (C), the preferable range of the total content of the above component (A) and component (B) may be the preferable range of the total content of component (A) and component (B) in the additive for hydraulic composition excluding component (C).

[0046] In the additive for hydraulic composition of the present invention, the mass ratio (B) / (A) of the content of component (B) to the content of component (A) is preferably 0.0001 or more, more preferably 0.0002 or more, still more preferably 0.0005 or more, even more preferably 0.001 or more from the perspective of preventing the generation of slime and shape change of the hydraulic composition, and preferably 5 or less, more preferably 2 or less, still more preferably 0.5 or less, even more preferably 0.05 or less from the perspective of the storage stability of the additive for hydraulic composition.

[0047] <(C) component> The additive for hydraulic composition of the present invention can optionally contain a (C) flash setting agent [hereinafter also referred to as component (C)]. The flash setting agent can be used in any form such as powdery, liquid, or a combination thereof. Examples of the flash setting agent include one or more flash setting agents selected from cement mineral-based flash setting agents and aluminum-based flash setting agents.

[0048] Examples of the cement mineral-based quick-setting agent of component (C) include one or more selected from calcium aluminate, calcium sulfoaluminate, and calcium aluminate. Examples of the aluminum-based quick-setting agent of component (C) include one or more selected from aluminum salts containing aluminum hydroxide, sodium aluminate, potassium aluminate, aluminum sulfate, aluminum chloride, potassium aluminum sulfate, potassium alum, iron alum, ammonium iron alum, and the like. From the viewpoints of strength development and suppression of the generation and shape change of the set of the hydraulic composition, component (C) is preferably one or more selected from calcium aluminate, calcium sulfoaluminate, calcium aluminate, aluminum sulfate, sodium aluminate, and aluminum sulfate, more preferably one or more selected from calcium aluminate, calcium sulfoaluminate, and aluminum sulfate, still more preferably one or more selected from calcium aluminate and aluminum sulfate, and still more preferably those containing aluminum sulfate. Component (C) may contain gypsum, alkali carbonates such as sodium carbonate, potassium carbonate, and sodium hydrogen carbonate, sodium sulfate, and calcium hydroxide.

[0049] As the quick-setting agent of component (C), those such as Denka's Denka Natomic series, Denka Natomic US-32, Denka Natomic US-50, Denka Natomic TYPE-5, Denka Natomic TYPE-10, Denka Natomic Z, Natomic L, Natomic LSA, Natomic USS, Natomic HSS, Denka Σ Shot V, Pacific Material Co., Ltd.'s Pacific Shot Master series, Pacific Shot Master A, Pacific Shot Master A (for high strength), Pacific Shot Master H, Pozolith Solutions Co., Ltd.'s Master Rock series, Master Rock SA161, Master Rock SA167, Master Rock SA178, Master Rock SA143, Master Rock SA446, Seeka Japan Co., Ltd.'s Signit series, Signit P10AF, Signit L53AF, Signit U, etc. can be used.

[0050] <Calcium aluminate> Calcium aluminate (hereinafter referred to as CA) is a general term for compounds mainly composed of CaO and Al2O3 and having hydration activity. A part of CaO and / or Al2O3 is replaced by alkali metal oxides, alkaline earth metal oxides, silicon oxide, titanium oxide, iron oxide, alkali metal halides, alkaline earth metal halides, alkali metal sulfates, and alkaline earth metal sulfates, etc. Or a substance in which these are dissolved in a small amount in a compound mainly composed of CaO and Al2O3. CA may be either crystalline or amorphous.

[0051] Specific examples of crystalline CA are, when CaO is C and Al2O3 is A, C3A, C14A5 in which an alkali metal is dissolved in it, CA, C12A7, C11A7·CaF2, C4A·Fe2O3, and C3A3·CaSO4, etc. Further, these compounds may contain, for example, Na2O, K2O, Li2O. Amorphous calcium aluminate is preferred because of its good flash setting property.

[0052] Note that the calcium aluminate used in this embodiment may be contaminated with trace amounts of alkali metals and / or alkaline earth metals from industrial raw materials, and there is a possibility that CA containing these alkali metals and / or alkaline earth metals is partially generated. However, it is not restricted by the presence of these small amounts of alkali metals and / or alkaline earth metals at all.

[0053] The CaO / Al2O3 molar ratio of calcium aluminate is not particularly limited. However, considering the early strength development property, the molar ratio is preferably 2.0 or more and 3.0 or less, and more preferably 2.2 or more and 2.8 or less. When the molar ratio is 2.0 or more, the initial setting property can be improved. When it is 3.0 or less, it is easy to obtain good long-term strength development property.

[0054] The Blaine specific surface area of calcium aluminate (hereinafter sometimes simply referred to as "Blaine") is 4,000 cm 28,000 cm² / g or more 2 preferably 5,000 cm² / g or less, and more preferably 7,000 cm² / g or more 2 / g or less. When the specific surface area is 4,000 cm² / g or more and 8,000 cm² / g or less, the initial strength development property can be easily obtained, and the workability of mortar and / or concrete during spraying can be improved. 2 2 2 8,000 cm² / g or less, the initial strength development property can be easily obtained, and the workability of mortar and / or concrete during spraying can be improved. 2 / g or less, the initial strength development property can be easily obtained, and the workability of mortar and / or concrete during spraying can be improved.

[0055] <Gypsum> Gypsum is effective for promoting the loss of fluidity immediately after mixing cement mortar or cement concrete and for promoting the strength development property in about one day. Although not particularly limited as gypsum, for example, any gypsum such as potassium gypsum, chromium gypsum, iron gypsum, ammonium gypsum, sodium gypsum, natural gypsum, etc. can be used and used in combination. In particular, as those that cause the loss of fluidity of cement mortar or cement concrete, it is preferable to contain at least one selected from the group consisting of potassium gypsum, sodium gypsum, and ammonium gypsum.

[0056] <Calcium hydroxide> As the calcium hydroxide, any of anhydrous, hemihydrate, and dihydrate calcium hydroxide can be used. Among these, anhydrous calcium hydroxide is preferable from the viewpoint of good strength development property. The particle size of calcium hydroxide is preferably 2,000 cm² / g or more in terms of Blaine specific surface area from the viewpoint of initial strength development property, and more preferably 3,000 cm² / g or more and 6,000 cm² / g or less. The Blaine specific surface area value in this specification can be determined in accordance with JIS R 5201 (Physical test methods for cement). 2 preferably 3,000 cm² / g or more 2 and more preferably 6,000 cm² / g or less. The Blaine specific surface area value in this specification can be determined in accordance with JIS R 5201 (Physical test methods for cement). 2 / g or less. The Blaine specific surface area value in this specification can be determined in accordance with JIS R 5201 (Physical test methods for cement).

[0057] <Calcium hydroxide> Calcium hydroxide is an effective material for ensuring extremely early fluidity reduction and long-term strength development. Calcium hydroxide is not particularly limited, but includes slaked lime generated when quicklime hydrates, and carbide slag generated when carbide hydrates. Commercially available calcium hydroxide can also be used, and any combination of the above is also possible.

[0058] The Blaine specific surface area of calcium hydroxide is preferably 5,000 cm 2 / g or more and 15,000 cm 2 / g or less, and more preferably 7,000 cm 2 / g or more and 13,000 cm 2 / g or less. When the specific surface area is 5,000 cm 2 / g or more and 15,000 cm 2 / g or less, it is possible to ensure flash setting properties and long-term strength development properties, and it is easy to obtain good initial strength development properties.

[0059] <Alkali carbonate> Alkali carbonate refers to alkali metal carbonate salts, which can significantly improve the setting properties and initial strength development properties of powdered flash setting agents. Alkali carbonates are not particularly limited, and examples include lithium carbonate, sodium carbonate, sesquicarbonate of sodium, potassium carbonate, sodium bicarbonate, and sodium hydrogen carbonate. Particularly effective for setting and initial strength development are sodium carbonate, potassium carbonate, sesquicarbonate of sodium, sodium bicarbonate, and sodium hydrogen carbonate, and it is also possible to combine one or more of these. Preferably, it is at least one selected from the group consisting of sodium carbonate, sesquicarbonate of sodium, sodium bicarbonate, and potassium carbonate.

[0060] When the additive for hydraulic compositions of the present invention contains component (C), the additive for hydraulic compositions of the present invention contains component (A) preferably at 1% by mass or more, more preferably at 2% by mass or more, still more preferably at 4% by mass or more, and preferably at 25% by mass or less, more preferably at 20% by mass or less, still more preferably at 10% by mass or less, even more preferably at 6% by mass or less, from the viewpoints of suppressing the generation of slime and shape change of the hydraulic composition and the strength development property.

[0061] When the additive for hydraulic compositions of the present invention contains component (C), the additive for hydraulic compositions of the present invention contains component (B) preferably at 0.01% by mass or more, more preferably at 0.04% by mass or more, still more preferably at 0.1% by mass or more, and preferably at 1% by mass or less, more preferably at 0.8% by mass or less, still more preferably at 0.4% by mass or less, even more preferably at 0.25% by mass or less, from the viewpoints of suppressing the generation of slime and shape change of the hydraulic composition and the strength development property.

[0062] When the additive for hydraulic compositions of the present invention contains component (C), the additive for hydraulic compositions of the present invention contains components (A) and (B) in total preferably at 1% by mass or more, more preferably at 2% by mass or more, still more preferably at 4% by mass or more, and, for example, at 25% by mass or less, further at 20% by mass or less, further at 10% by mass or less, further at 6% by mass or less, from the viewpoints of suppressing the generation of slime and shape change of the hydraulic composition and the strength development property.

[0063] When the additive for hydraulic compositions of the present invention contains component (C), in the additive for hydraulic compositions of the present invention, the mass ratio (B) / (A) of the content of component (B) to the content of component (A) is preferably 0.0001 or more, more preferably 0.0002 or more, still more preferably 0.0005 or more, even more preferably 0.001 or more, from the viewpoint of preventing the generation of slime and shape change of the hydraulic composition, and preferably 5 or less, more preferably 2 or less, still more preferably 0.5 or less, even more preferably 0.05 or less, from the viewpoint of the storage stability of the additive for hydraulic compositions.

[0064] When the additive for hydraulic composition of the present invention contains the component (C), the additive for hydraulic composition of the present invention preferably contains the component (C) in an amount of 75% by mass or more, more preferably 85% by mass or more, still more preferably 92% by mass or more, from the viewpoints of suppressing the generation and shape change of slime in the hydraulic composition and the strength development property, and preferably 99% by mass or less, more preferably 97% by mass or less, still more preferably 95% by mass or less from the viewpoint of suppressing the generation and shape change of slime in the hydraulic composition.

[0065] In the additive for hydraulic composition of the present invention, the mass ratio (C) / (A) of the content of the component (C) to the content of the component (A) is preferably 2 or more, more preferably 4 or more, still more preferably 9 or more, even more preferably 15 or more from the viewpoints of strength development property and discharge and molding workability, and preferably 450 or less, more preferably 200 or less, still more preferably 100 or less, even more preferably 50 or less from the viewpoint of suppressing the generation and shape change of slime in the hydraulic composition.

[0066] The additive for hydraulic composition of the present invention may optionally contain one or more of a dispersant, an antifoaming agent, a preservative, an early strength component of the hydraulic composition, a hardening accelerator, a hardening retarder, an AE agent, a waterproof agent, a shrinkage reducing agent, a rust preventive agent, a crack reducing agent, a pH adjuster, a thickening agent, a separation reducing agent, a dust reducing agent, a slime inhibitor, a sag prevention agent, and other surfactants (excluding those corresponding to the component (B)).

[0067] The additive for hydraulic composition of the present invention is an additive for hydraulic composition, and is preferably an additive composition for sprayed hydraulic composition from the viewpoint of suppressing the generation and shape change of slime in the hydraulic composition.

[0068] <Manufacturing method of additive for hydraulic composition> The present invention provides a method for manufacturing an additive for hydraulic composition, which comprises mixing (A) a clay mineral (which is the component (A)) and one or more selected from (B) an acrylic acid polymer and a cellulose polymer (which is the component (B)). In the method for producing an additive for a hydraulic composition of the present invention, further, a flash setting agent [(C) component] can be optionally mixed. In the method for producing an additive for a hydraulic composition of the present invention, the preferred embodiments of the (A) component, the (B) component, and the (C) component are the same as the preferred embodiments of the respective components described in the additive for a hydraulic composition of the present invention above. Further, in producing the additive for a hydraulic composition of the present invention, optional components described in the additive for a hydraulic composition can be mixed. The preferred mixing amounts of these components can be applied by reading the preferred contents of the respective components in the additive for a hydraulic composition as mixing amounts. Also, specific examples of the method for producing an additive for a hydraulic composition of the present invention will be described in detail in the spraying method of the present invention. However, the method for producing an additive for a hydraulic composition of the present invention is not limited to the specifically described embodiments at all.

[0069] <Kit for producing additive for hydraulic composition> The present invention provides a kit for producing an additive for a hydraulic composition, which is composed of a plurality of agents including (A) a clay mineral [(A) component] or at least one selected from (B) an acrylic polymer and a cellulose polymer [(B) component], wherein the (A) component and the (B) component are contained in different agents. Examples of the kit of the present invention include a kit composed of an agent containing the (A) component and not containing the (B) component and an agent containing the (B) component and not containing the (A) component.

[0070] Specific examples and preferred examples of the (A) component and the (B) component in the kit of the present invention are the same as the preferred embodiments of the respective components described in the additive for a hydraulic composition of the present invention. Matters described in the additive for a hydraulic composition of the present invention can be appropriately applied to the kit of the present invention. Also, in the kit of the present invention, when using an optional component described in the additive for a hydraulic composition of the present invention, the optional component can be contained in an agent different from an agent containing the (A) component, an agent containing the (B) component, an agent containing the (A) component, and an agent containing the (B) component.

[0071] In each agent constituting the kit of the present invention, the contents of the component (A) and the component (B) may be amounts such that, for example, an additive for a hydraulic composition of the present invention containing these components in the above ranges of contents or mass ratios can be produced.

[0072] A plurality of agents containing the component (A) or the component (B) are mixed to prepare a predetermined additive for a hydraulic composition. The agent containing the component (A) preferably contains the component (A) in an amount of 3% by mass or more, further 5% by mass or more, further 25% by mass or more, and 100% by mass or less, further 90% by mass or less, and may contain 100% by mass. Also, the agent containing the component (B) preferably contains the component (B) in an amount of 5% by mass or more, further 10% by mass or more, further 20% by mass or more, and 100% by mass or less, further 90% by mass or less, and may contain 100% by mass.

[0073] <Hydraulic composition> The present invention provides a hydraulic composition containing the additive for a hydraulic composition of the present invention, a hydraulic powder, and water. The hydraulic composition of the present invention may be a hydraulic composition obtained by blending the additive for a hydraulic composition of the present invention, a hydraulic powder, and water. Also, the hydraulic composition of the present invention may optionally contain a (C) flash setting agent [(C) component]. In the hydraulic composition of the present invention, the preferred embodiments of the additive for a hydraulic composition, that is, the preferred embodiments and their contents of the component (A), the component (B), and the component (C) are the same as the preferred embodiments described for the additive for a hydraulic composition of the present invention above.

[0074] <Hydraulic powder> The hydraulic powder used in the hydraulic composition of the present invention is a powder that hardens by mixing with water. Examples include ordinary Portland cement, early-strength Portland cement, ultra-early-strength Portland cement, sulfate-resistant Portland cement, low-heat Portland cement, moderate-heat Portland cement, white Portland cement, alumina cement, eco-cement (such as JIS R 5214, etc.). Among these, from the perspective of the spread of the hydraulic composition, cement selected from early-strength Portland cement, ordinary Portland cement, sulfate-resistant Portland cement, and white Portland cement is preferred, and early-strength Portland cement and ordinary Portland cement are more preferred.

[0075] In addition, the hydraulic powder may contain blast furnace slag, fly ash, silica fume, anhydrous gypsum, etc., and may also contain non-hydraulic fine limestone powder, etc. As the hydraulic powder, blast furnace cement, fly ash cement, silica fume cement, etc., in which cement is mixed with blast furnace slag, fly ash, silica fume, etc., may be used.

[0076] <Water> The hydraulic composition of the present invention contains water. Examples of water include tap water, groundwater, lake water, river water, etc.

[0077] <Composition, etc.> The hydraulic composition of the present invention contains the additive for the hydraulic composition of the present invention, preferably 0.02% by mass or more, more preferably 0.05% by mass or more, still more preferably 0.1% by mass or more, even more preferably 0.5% by mass or more, from the perspective of suppressing the generation and shape change of slump in the hydraulic composition with respect to the hydraulic powder in the hydraulic composition, and preferably 10% by mass or less, more preferably 5% by mass or less, still more preferably 2% by mass or less, from the perspective of the molding workability, pumping workability, and discharging workability of the hydraulic composition.

[0078] The hydraulic composition of the present invention contains component (A) preferably at 0.02% by mass or more, more preferably 0.05% by mass or more, still more preferably 0.1% by mass or more, even more preferably 0.5% by mass or more, based on the hydraulic powder in the hydraulic composition, from the viewpoint of suppressing the generation of slump and shape change of the hydraulic composition; and preferably at 10% by mass or less, more preferably 5% by mass or less, still more preferably 2% by mass or less, from the viewpoints of the molding workability, pumping workability, and discharging workability of the hydraulic composition.

[0079] The hydraulic composition of the present invention contains component (B) preferably at 0.001% by mass or more, more preferably 0.004% by mass or more, still more preferably 0.01% by mass or more, even more preferably 0.02% by mass or more, even more preferably 0.05% by mass or more, based on the hydraulic powder in the hydraulic composition, from the viewpoint of suppressing the generation of slump and shape change of the hydraulic composition; and preferably at 2% by mass or less, more preferably 1% by mass or less, still more preferably 0.5% by mass or less, even more preferably 0.1% by mass or less, even more preferably 0.07% by mass or less, from the viewpoints of the molding workability, pumping workability, and discharging workability of the hydraulic composition.

[0080] In the hydraulic composition of the present invention, the mass ratio (B) / (A) of the content of component (B) to the content of component (A) is preferably 0.0001 or more, more preferably 0.0002 or more, still more preferably 0.0005 or more, and preferably 5 or less, more preferably 2 or less, still more preferably 0.5 or less, even more preferably 0.05 or less, from the viewpoint of suppressing the generation of slump and shape change of the hydraulic composition.

[0081] When the hydraulic composition of the present invention contains the component (C), the hydraulic composition of the present invention contains the component (C) in an amount of preferably 1% by mass or more, more preferably 4% by mass or more, still more preferably 7% by mass or more, based on the hydraulic powder in the hydraulic composition, from the viewpoints of suppressing the generation and shape change of slump of the hydraulic composition, strength development, and discharge and molding workability. And from the viewpoint of suppressing the generation and shape change of slump of the hydraulic composition, it preferably contains 14% by mass or less, more preferably 12% by mass or less, still more preferably 10% by mass or less.

[0082] When the hydraulic composition of the present invention contains the component (C), in the hydraulic composition of the present invention, the mass ratio (C) / (A) of the content of the component (C) to the content of the component (A) is preferably 2 or more, more preferably 4 or more, still more preferably 9 or more, even more preferably 15 or more, from the viewpoints of strength development and discharge and molding workability. And from the viewpoint of suppressing the generation and shape change of slump of the hydraulic composition, it is preferably 450 or less, more preferably 200 or less, still more preferably 100 or less, even more preferably 50 or less.

[0083] The hydraulic composition of the present invention has a water / hydraulic powder ratio (W / C) of preferably 30% by mass or more, more preferably 35% by mass or more, still more preferably 40% by mass or more, from the viewpoints of suppressing the generation and shape change of slump of the hydraulic composition and strength development. And it is preferably 80% by mass or less, more preferably 70% by mass or less, still more preferably 65% by mass or less. That is, the hydraulic composition of the present invention contains water in an amount of preferably 30 parts by mass or more, more preferably 35 parts by mass or more, still more preferably 40 parts by mass or more, based on 100 parts by mass of the hydraulic powder contained in the hydraulic composition, from the viewpoints of suppressing the generation and shape change of slump of the hydraulic composition and strength development. And it is preferably 80 parts by mass or less, more preferably 70 parts by mass or less, still more preferably 65 parts by mass or less. Note that this water / hydraulic powder ratio (W / C) represents the ratio of water to the hydraulic powder in the hydraulic composition as a mass percentage (mass%), and is calculated by (water / hydraulic powder)×100. In addition, when the hydraulic powder includes powders selected from powders having properties of hardening by a hydration reaction such as cement, powders having a pozzolanic action, latent hydraulic powders, and stone powder (calcium carbonate powder), in the present invention, their amounts are also included in the amount of the hydraulic powder. However, when these components are included in the (C) flash set retarder, the components included in the (C) flash set retarder are not included in the amount of the hydraulic powder. Further, when the powder having properties of hardening by a hydration reaction contains a high-strength admixture, the amount of the high-strength admixture is also included in the amount of the hydraulic powder. This also applies to other parts by mass related to the mass of the hydraulic powder.

[0084] <Aggregate> The hydraulic composition of the present invention can optionally contain an aggregate. Examples of the aggregate include aggregates selected from fine aggregates and coarse aggregates. Examples of the fine aggregate include those defined by No. 2311 in JIS A 0203-2014. Examples of the fine aggregate include river sand, land sand, mountain sand, sea sand, lime sand, silica sand, and crushed sand thereof, blast furnace slag fine aggregate, ferronickel slag fine aggregate, lightweight fine aggregate (artificial and natural), and recycled fine aggregate. Examples of the coarse aggregate include those defined by No. 2312 in JIS A 0203-2014. For example, examples of the coarse aggregate include river gravel, land gravel, mountain gravel, sea gravel, lime gravel, crushed stone thereof, blast furnace slag coarse aggregate, ferronickel slag coarse aggregate, lightweight coarse aggregate (artificial and natural), and recycled coarse aggregate. The fine aggregate and the coarse aggregate may be used by mixing those of different types, or a single type may be used. The hydraulic composition of the present invention can contain a fine aggregate as an aggregate. The amount of the fine aggregate used in the hydraulic composition of the present invention is preferably 500 kg / m 3 or more, more preferably 600 kg / m 3 or more, and preferably 2000 kg / m 3 or less, more preferably 1700 kg / m 3 or less. In the hydraulic composition of the present invention, the fine aggregate ratio is preferably 35% or more, more preferably 45% or more, and preferably 100% or less, more preferably 70% or less, still more preferably 65% or less. Here, the fine aggregate ratio is the volume content ratio of the fine aggregate in all the aggregates.

[0085] The hydraulic composition of the present invention may optionally contain one or more of a dispersant, a high-performance water reducing agent, a high-performance AE water reducing agent, an AE water reducing agent, a water reducing agent containing a fluidizing agent, an expansion agent, a hardening accelerator, a hardening retarder, a polymer for cement, a foaming agent, a waterproof agent, a rust preventive agent, a shrinkage reducing agent, a pigment, a fiber, a water repellent, a white efflorescence preventive agent, a thickening agent, etc. (however, excluding those corresponding to the component (B)).

[0086] The hydraulic composition of the present invention may be a hydraulic composition for spraying, plastering, vibration molding products, centrifugal molding products, concrete structures, or 3D printers. From the viewpoints of suppressing the generation of slump and shape change of the hydraulic composition and workability, it is preferably a hydraulic composition for spraying.

[0087] When the hydraulic composition of the present invention is used as a hydraulic composition for spraying, the target surface of the hydraulic composition of the present invention includes tunnels such as roads, railways, and water conduits, slopes formed by excavating natural ground, embankments, etc., underground spaces, and concrete structures to be repaired by the spraying method.

[0088] <Manufacturing method of hydraulic composition> The present invention provides a method for manufacturing a hydraulic composition, which comprises mixing an additive for the hydraulic composition of the present invention, a hydraulic powder, and water. Further, the present invention provides a method for manufacturing a hydraulic composition, which comprises mixing (A) a clay mineral (which is the component (A)) and one or more selected from (B) an acrylic polymer and a cellulose polymer (which is the component (B)) to obtain an additive for the hydraulic composition, and mixing the additive for the hydraulic composition, the hydraulic powder, and water to obtain a hydraulic composition. In the manufacturing method of the hydraulic composition of the present invention, further, (C) a flash setting agent (which is the component (C)) can be optionally mixed. In the method for producing the hydraulic composition of the present invention, the preferred embodiments of the additive for the hydraulic composition, component (A), component (B), component (C), hydraulic powder, and water are the same as the preferred embodiments of the respective components described in the additive for the hydraulic composition of the present invention and the hydraulic composition of the present invention. Further, in producing the hydraulic composition of the present invention, optional components described in the above hydraulic composition can be mixed. The preferred mixing amounts and mass ratios of these components can be applied by reading the preferred contents or mass ratios of the respective components in the above additive for the hydraulic composition or the hydraulic composition as the mixing amounts or mass ratios of the mixing amounts. Further, specific examples of the method for producing the hydraulic composition of the present invention will be described in detail in the spraying method of the present invention. However, the method for producing the hydraulic composition of the present invention is not limited to the specifically described embodiments.

[0089] In the method for producing the hydraulic composition of the present invention, when using the additive for the hydraulic composition of the present invention, the mixing amount of component (A) is preferably 0.02% by mass or more, more preferably 0.05% by mass or more, still more preferably 0.1% by mass or more, even more preferably 0.5% by mass or more, from the viewpoint of suppressing the generation and shape change of the noro of the hydraulic composition with respect to the hydraulic powder in the hydraulic composition, and preferably 10% by mass or less, more preferably 5% by mass or less, still more preferably 2% by mass or less, from the viewpoints of the molding workability, pumping workability, and discharging workability of the hydraulic composition. The additive for the hydraulic composition of the present invention and the hydraulic powder are mixed accordingly.

[0090] In the method for producing a hydraulic composition of the present invention, when using the additive for a hydraulic composition of the present invention, the mixing amount of component (B) is preferably 0.001% by mass or more, more preferably 0.004% by mass or more, still more preferably 0.01% by mass or more, even more preferably 0.02% by mass or more, even more preferably 0.05% by mass or more, from the viewpoint of suppressing the generation and shape change of the slump of the hydraulic composition with respect to the hydraulic powder in the hydraulic composition. And, from the viewpoints of the molding workability, pumping workability, and discharging workability of the hydraulic composition, it is preferably 2% by mass or less, more preferably 1% by mass or less, still more preferably 0.5% by mass or less, even more preferably 0.1% by mass or less, even more preferably 0.07% by mass or less. The additive for a hydraulic composition of the present invention and the hydraulic powder are mixed so as to be.

[0091] <Spraying method> The present invention provides a spraying method in which an additive for a hydraulic composition of the present invention, a hydraulic powder, and water are mixed to obtain a hydraulic composition, and the hydraulic composition is sprayed onto a target surface. Further, the present invention provides a spraying method in which (A) a clay mineral [as component (A)] and one or more selected from an acrylic acid polymer and a cellulose polymer [as component (B)] are mixed to obtain an additive for a hydraulic composition, the additive for a hydraulic composition, a hydraulic powder, and water are mixed to obtain a hydraulic composition, and the hydraulic composition is sprayed onto a target surface. In the spraying method of the present invention, a (C) quick-setting agent may be further mixed into the above hydraulic composition, and the sprayed hydraulic composition mixed with the (C) quick-setting agent may be sprayed onto an object. In the spraying method of the present invention, the preferred embodiments of the additive for a hydraulic composition, component (A), component (B), hydraulic powder, water, and other optional components are the same as those described in the additive for a hydraulic composition and the hydraulic composition of the present invention. The spraying method of the present invention can apply the aspects described in the additive for hydraulic composition and the hydraulic composition of the present invention. The preferable content and mass ratio of each component in the additive for hydraulic composition and the hydraulic composition of the present invention can be replaced with the preferable mixing amount or mass ratio of the mixing amount of each component and applied to the spraying method of the present invention.

[0092] The spraying method of the present invention preferably includes a method in which a hydraulic composition and a (C) quick-setting agent are separately pressure-fed and joined and mixed, or a method in which a quick-setting agent slurry obtained by adding water to a powdered quick-setting agent and slurrying it is joined and mixed with the hydraulic composition and sprayed. Either a dry spraying method or a wet spraying method can be used. Examples of the dry spraying method include a method in which a hydraulic powder and an aggregate are mixed, pneumatically fed, and water and a (C) quick-setting agent are joined and mixed and sprayed in a wet state. Examples of the wet spraying method include a method in which a hydraulic powder, an aggregate, and water are mixed and kneaded, pneumatically fed, and a (C) quick-setting agent is joined and mixed and sprayed. The component (A) and the component (B), and further the additive for hydraulic composition of the present invention can be mixed with the hydraulic powder in advance or added to water in advance and then mixed with the hydraulic composition. When the additive for hydraulic composition of the present invention contains the component (C), the additive for hydraulic composition of the present invention can also be used as the (C) quick-setting agent.

[0093] Specific examples will be given and the spraying method of the present invention will be described in detail. Note that the spraying method of the present invention is not limited to this specific example at all. In the spraying step of the present invention, it includes an additive manufacturing step for hydraulic composition, a hydraulic composition manufacturing step, and a spraying step.

[0094] <Additive Manufacturing Step for Hydraulic Composition> In the spraying method of the present invention, first, component (A) and component (B) are mixed to obtain an additive for a hydraulic composition. In this step, for example, a mixing mixer such as a pan-type forced mixer, a twin-shaft forced mixer, a tilting mixer, a Hobart mixer, a rotary mixer, a W-type mixer, a V-type mixer, a drum-type mixer, a conical screw-type mixer, a ribbon mixer, a tumbler mixer, a double-cone mixer, a mill mixer, a juicer mixer, a hand mixer, a Nauta mixer, etc. can be used to mix component (A) and component (B).

[0095] <Hydraulic composition manufacturing process> In the spraying method of the present invention, next, the additive for a hydraulic composition produced in the additive for a hydraulic composition production process, a hydraulic powder, and water are mixed to produce a hydraulic composition. The water / hydraulic powder ratio (W / C) of this hydraulic composition [mass percentage (mass%) of water and hydraulic powder in the hydraulic composition] is preferably 30% by mass or more, more preferably 35% by mass or more, still more preferably 40% by mass or more, and preferably 80% by mass or less, more preferably 70% by mass or less, still more preferably 65% by mass or less, from the viewpoints of suppressing the generation and shape change of the slump of the hydraulic composition and workability.

[0096] In the present invention, the mixing of the additive for a hydraulic composition, a hydraulic powder, water, and other optional components of the present invention, and the mixing of component (A), component (B), a hydraulic powder, water, and other optional components can be carried out by known methods. For example, a method of simultaneously mixing the additive for a hydraulic composition, a hydraulic powder, and water of the present invention, or a method of simultaneously mixing component (A), component (B), a hydraulic powder, and water can be mentioned. In this step, for example, a mixing mixer such as a pan-type forced mixer, a twin-shaft forced mixer, a tilting mixer, a Hobart mixer, a rotary mixer, a Hobart mixer, a W-type mixer, a V-type mixer, a drum-type mixer, a conical screw-type mixer, a ribbon mixer, a tumbler mixer, a double-cone mixer, a mill mixer, a juicer mixer, a hand mixer, a Nauta mixer, etc., or manually in a sealed container, these components can be mixed.

[0097] In the present invention, a spraying hydraulic composition can be produced by optionally adding (C) a quick-setting agent to a hydraulic composition obtained by mixing an additive for hydraulic composition, hydraulic powder, and water. The mixing of the hydraulic composition and (C) the quick-setting agent can be carried out, for example, by a general spraying method in which the hydraulic composition and (C) the quick-setting agent are pneumatically transported and mixed by confluence.

[0098] <Spraying process> In the spraying method of the present invention, the thus-prepared hydraulic composition or the spraying hydraulic composition is sprayed onto an object. The spraying method of the present invention can be carried out by conventional spraying equipment. The spraying equipment only needs to be able to perform spraying without hindrance. For example, for the pneumatic transportation of the hydraulic composition, "Ariba 280" manufactured by Ariba Co., Ltd. etc. is used, and for the pneumatic transportation of (C) the quick-setting agent, "Natomcrete" manufactured by Chiyoda Manufacturing Co., Ltd. etc. is used, and it is possible to mix both to prepare a spraying hydraulic composition and perform spraying.

Examples

[0099] In the examples and comparative examples, a hydraulic composition was produced with the formulations shown in Table 1. Also, in the examples and comparative examples, the following components (A), (B), and (C) were used.

[0100]

Table 1

[0101] The components in Table 1 are as follows. W: Tap water C: Hydraulic powder, ordinary Portland cement (two-component mixture: Taiheiyo Cement / Sumitomo Osaka Cement = 1 / 1, mass ratio), density 3.16 g / cm 3 S: Fine aggregate (S): Shanyang-produced mountain sand, density 2.55 g / cm 3

[0102] <Component (A)> ·A-1: TB-250, smectite content 38.4 mass%, swelling degree 14 mL / 2 g, manufactured by Tachibana Material Co., Ltd. · A-2: Kasaoka clay, smectite content 20.8% by mass, swelling degree 3.5 mL / 2 g, manufactured by Kasanen Kogyo Co., Ltd. · A-3: Neoclay, smectite content 46.9% by mass, swelling degree 18 mL / 2 g, manufactured by Hoojun Co., Ltd. · A-4: Kunigel GS, smectite content 53.8% by mass, swelling degree 33 mL / 2 g, manufactured by Kunimine Industries Co., Ltd. · A-5: Smecton SA, smectite content 99.2% by mass, swelling degree 45 mL / 2 g, manufactured by Kunimine Industries Co., Ltd. Note that the smectite content and swelling degree of the component (A) were measured according to the above-mentioned measurement methods for smectite content and swelling degree, respectively.

[0103] <(Component B)> (Cellulose polymer: In the table, sodium carboxymethyl cellulose salt is abbreviated as CMC.) · B-1: Sodium carboxymethyl cellulose salt, degree of etherification 0.87, average particle diameter 65 μm, weight-average molecular weight 4,023,000, viscosity of 1% by mass (25 °C) 4400 mPa·s, CMC Daicel FH 4000A, manufactured by Daicel Miraiz Co., Ltd. · B-2: Sodium carboxymethyl cellulose salt, degree of etherification 0.74, average particle diameter 90 μm, weight-average molecular weight 364,000, viscosity of 1% by mass aqueous solution (25 °C) 20 mPa·s, CMC Daicel 1110, manufactured by Daicel Miraiz Co., Ltd. · B-3: Sodium carboxymethyl cellulose salt, degree of etherification 0.7, average particle diameter 116 μm, weight-average molecular weight 560,000, viscosity of 1% by mass aqueous solution (25 °C) 45 mPa·s, CMC Daicel 1130, manufactured by Daicel Miraiz Co., Ltd. · B-4: Sodium carboxymethyl cellulose salt, degree of etherification 0.68, average particle diameter 89 μm, weight-average molecular weight 1,096,000, viscosity of 1% by mass aqueous solution (25 °C) 200 mPa·s, CMC Daicel 1160, manufactured by Daicel Miraiz Co., Ltd. · B-5: Sodium carboxymethyl cellulose, degree of etherification 1.27, average particle size 44 μm, weight-average molecular weight 753,000, viscosity of 1 mass% aqueous solution (25 °C) 45 mPa·s, CMC Daicel 1330, manufactured by Daicel Miraiz Co., Ltd. (Acrylic acid polymer) · B-6: Polyacrylic acid, weight-average molecular weight 5,000, average particle size 164 μm, viscosity of 1 mass% aqueous solution (25 °C) 3 mPa·s, PAA5000, manufactured by Fujifilm Wako Pure Chemical Corporation · B-7: Polyacrylic acid, weight-average molecular weight 25,000, average particle size 246 μm, viscosity of 1 mass% aqueous solution (25 °C) 40 mPa·s, PAA25,000, manufactured by Fujifilm Wako Pure Chemical Corporation · B-8: Polyacrylic acid, weight-average molecular weight 250,000, average particle size 152 μm, viscosity of 1 mass% aqueous solution (25 °C) 140 mPa·s, PAA250,000, manufactured by Fujifilm Wako Pure Chemical Corporation · B-9: Polyacrylic acid, weight-average molecular weight 1,000,000, average particle size 8 μm, viscosity of 1 mass% aqueous solution (25 °C) 2,500 mPa·s, PAA1,000,000, manufactured by Fujifilm Wako Pure Chemical Corporation (B) The degree of etherification, smectite content, swelling degree, average particle size, weight-average molecular weight, and 1 mass% viscosity of the component were measured according to the measurement methods of the above degree of etherification, smectite content, swelling degree, average particle size, weight-average molecular weight, and 1 mass% viscosity, respectively.

[0104] <(C) component: Quick-setting agent> · C-1: Calcium aluminate-based quick-setting agent: A powder quick-setting agent mainly composed of calcium aluminate

[0105] <Mortar shape retention test> (1) Preparation of hydraulic composition (mortar) To a Hobart mixer (manufactured by Kansai Kiki Seisakusho Co., Ltd., KC-8), hydraulic powder (C) and sand (S) were added according to the formulation shown in Table 1, and dry mixing was carried out for 10 seconds. Water (W) was added to the dry-mixed mixture of hydraulic powder (C) and sand (S), and the mortars shown in Tables 2 and 3 were prepared by stirring at a low speed for 2 minutes (stirring speed: revolution 62 rpm, rotation 141 rpm). Components (A) and (B) were added to the obtained mortar according to the method described in the table. When components (A) or (B) are added to the hydraulic powder in advance, each component was added to the hydraulic powder (C) and mixed, and the mortar was prepared according to the above steps using the obtained hydraulic composition mixture. When components (A) and / or (B) are added post-additively to the hydraulic composition, to the mortar prepared in the above step, component (A), component (B) or a mixture of components (A) and (B) was added, and the mortar was prepared by stirring at a high speed for 10 seconds (revolution: 125 rpm, rotation: 285 rpm). When using a mixture of component (A) and component (B), component (A) and component (B) were mixed manually in a sealed container, and an additive for hydraulic composition which is a mixture containing component (A) and component (B) at a predetermined ratio was prepared and used. The manual mixing of component (A) and component (B) in this sealed container was carried out by putting component (A) and component (B) into a 250 mL bottle container so that the total of component (A) and component (B) was 50 g, and shaking while manually inverting the bottle repeatedly for 60 seconds for mixing.

[0106] (2) Evaluation of shape retention In accordance with JIS R 5201, the mortar prepared in (1) above was filled into a flow cone (upper diameter 70 mm × lower diameter 100 mm × height 60 mm), pulled up vertically on a flow table, and the spread after 1 minute was measured as the initial mortar flow. In the measurement of the initial mortar flow, the value of the mortar diameter in the maximum direction of the spread mortar and the value of the mortar diameter in the direction perpendicular thereto were measured, and the average value thereof was calculated. The results are shown in Tables 2 and 3. From the viewpoint of ensuring shape retention, it is preferable that the initial mortar flow is smaller.

[0107]

Table 2

[0108]

Table 3

[0109] <Spraying test> (1) Preparation of hydraulic composition (mortar) To a Hobart mixer (manufactured by Kansai Equipment Manufacturing Co., Ltd., KC-8), hydraulic powder (C) and sand (S) were added according to the formulation shown in Table 1, and dry mixing was carried out for 10 seconds. Water (W) was added to the dry-mixed mixture of hydraulic powder (C) and sand (S), and stirring was performed at a low speed for 2 minutes (stirring speed: revolution 62 rpm, rotation 141 rpm) to prepare mortar. To the obtained mortar, an additive for hydraulic composition (including a (C) quick-setting agent if necessary) shown in Table 4 was added so as to obtain the blending amount shown in Table 4, and stirring was carried out by hand kneading for 5 seconds to obtain the hydraulic composition shown in Table 4. In the preparation of the hydraulic composition, the components (A) and (B) [component (C) if necessary] were previously blended at the ratio shown in Table 4, manually mixed in a sealed container, and an additive for hydraulic composition which is a mixture containing the components (A) and (B) [component (C) if necessary] at a predetermined ratio was prepared and used. The manual mixing of the components (A) and (B) in this sealed container was carried out by putting the components (A) and (B) into a 250 mL bottle container so that the total amount was 50 g, and shaking the bottle manually while repeatedly inverting it for 60 seconds for mixing. Similarly, when the additive for hydraulic composition contains the component (C), as described above, after creating a mixture containing the components (A) and (B) at a predetermined ratio, further at a predetermined ratio, the mixture containing the components (A) and (B) and the component (C) were put into a 250 mL bottle container so that the total amount was 50 g, and shaking the bottle manually while repeatedly inverting it for 60 seconds for mixing.

[0110] (2) Evaluation of norovirus generation rate 1,500 g of the hydraulic composition obtained in (1) was sprayed onto a wooden board 18 cm away from the injection port of a powder and granular material conveying device (Bress Rider, model number K-40, manufactured by Bress Co., Ltd.) using the powder and granular material conveying device. The pressure of the compressor connected to the powder and granular material conveying device was 0.6 MPa, and the diameter φ of the injection port was 3.5 cm. Those without norovirus adhered and accumulated only at the spraying locations, but for those with norovirus, it was confirmed that the paste component of the mortar and a small amount of fine aggregate flowed down directly below the spraying locations. The mass of the hydraulic composition that fell below the wooden board and the mass of the hydraulic composition that adhered 8 cm below the wooden board were measured, and the norovirus occurrence rate (%) was calculated from the following formula (1). The lower this norovirus occurrence rate, the more it can be said that the occurrence of norovirus is suppressed when the hydraulic composition is sprayed onto the target surface. Norovirus occurrence rate (%) = 100 × [(mass of the hydraulic composition that fell below the wooden board) + (mass of the hydraulic composition that adhered 8 cm below the wooden board)] / (total mass of the sprayed hydraulic composition) (1)

[0111]

Table 4

[0112] It was found that the hydraulic composition adhering to the wooden boards in Examples 2-7, 2-8, 2-10, 2-11, and 2-12 in which the additive for the hydraulic composition further contained component (C) hardened within 5 minutes after spraying and showed high strength development. On the other hand, it was confirmed that the hydraulic composition adhering to the wooden board in Example 2-9 in which the additive for the hydraulic composition did not contain component (C) did not harden within 5 minutes after spraying but gradually began to solidify.

[0113] <Hygroscopicity Evaluation of Additive for Hydraulic Composition> Component (A) and component (B) described in Table 5 were mixed at the ratios described in Table 5 to prepare an additive for the hydraulic composition. Component (A) and component (B) with a water content of approximately 8.5% by mass were used. This additive for the hydraulic composition was placed in an aluminum cup of about 2 g and left standing in an environment of 85% RH and 20°C. When storing the additive for hydraulic composition in a humidity atmosphere of 85% RH, a saturated potassium chloride aqueous solution was placed in the container for storing the additive for hydraulic composition to maintain the humidity in the container at 85% RH, and a cup containing the additive for hydraulic composition was placed and left still in the container with the humidity maintained at 85% RH. At this time, the cup was placed and left still in the container so that the additive for hydraulic composition did not come into contact with the saturated potassium chloride aqueous solution. After leaving it still in an environment of 85% RH and 20 °C for 17 hours, the additive for hydraulic composition was taken out, and the state of the additive (specifically, the fluidity of the additive and the presence or absence of lumps (clumps) in the additive) was visually confirmed. Also, the additive for hydraulic composition before standing and 17 hours after standing was subjected to strong heat loss at 105 °C for 1 hour, and the moisture content (mass %) of each additive for hydraulic composition was calculated from the mass loss amount. From the results of hygroscopicity, the additive for hydraulic composition of the example was excellent in storage stability.

[0114]

Table 5

Claims

1. An additive for a hydraulic composition, comprising (A) a clay mineral [hereinafter referred to as component (A)] and at least one selected from (B) an acrylic polymer and a cellulose polymer [hereinafter referred to as component (B)].

2. The additive for a hydraulic composition according to claim 1, wherein component (A) is bentonite.

3. The additive for a hydraulic composition according to claim 1 or 2, wherein component (B) is in powder form.

4. The additive for a hydraulic composition according to any one of claims 1 to 3, wherein component (B) is at least one selected from polyacrylic acid, carboxymethyl cellulose, and salts thereof.

5. The additive for a hydraulic composition according to any one of claims 1 to 4, wherein the mass ratio (B) / (A) of the content of component (B) to the content of component (A) is 0.0001 or more and 5 or less.

6. A method for producing an additive for a hydraulic composition, comprising mixing (A) a clay mineral and at least one selected from (B) an acrylic polymer and a cellulose polymer.

7. A method for producing a hydraulic composition, comprising mixing the additive for a hydraulic composition according to any one of claims 1 to 5, a hydraulic powder, and water to obtain a hydraulic composition.

8. A method for producing a hydraulic composition, comprising mixing (A) a clay mineral and at least one selected from (B) an acrylic polymer and a cellulose polymer [hereinafter referred to as component (B)] to obtain an additive for a hydraulic composition, and mixing the additive for a hydraulic composition, a hydraulic powder, and water to obtain a hydraulic composition.

9. The method for producing a hydraulic composition according to claim 8, wherein the additive for a hydraulic composition and the hydraulic powder are mixed such that the mixing amount of component (B) is 0.001% by mass or more and 2% by mass or less based on the hydraulic powder.

10. The method for producing a hydraulic composition according to any one of claims 7 to 9, which is for spraying.

11. A spraying method comprising mixing an additive for a hydraulic composition, a hydraulic powder, and water according to any one of claims 1 to 5 to obtain a hydraulic composition, and spraying the hydraulic composition onto a target surface.

12. A spraying method comprising obtaining an additive for a hydraulic composition by mixing (A) a clay mineral and (B) at least one selected from an acrylic acid polymer and a cellulose polymer, mixing the additive for a hydraulic composition, a hydraulic powder, and water to obtain a hydraulic composition, and spraying the hydraulic composition onto a target surface.

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