JP7421310B2 - Adhesion reducing agent for pipes for spraying hydraulic compositions - Google Patents

Description

The present invention relates to an agent for reducing the adhesion of a hydraulic composition for spraying to piping, a hydraulic composition for spraying, and a wet spraying method.

In order to prevent the collapse of exposed ground during tunnel excavation, a spraying method is used that uses quick-setting concrete containing a quick-setting agent. Among these construction methods, the so-called wet spraying method usually involves preparing shotcrete in a metering and mixing plant for cement, aggregate, and water installed at the excavation site, and then transporting it using an agitator vehicle to the spraying machine. Transfer to. Concrete and powder quick-setting agent are mixed using a line that air-feeds the concrete to the discharge port using the pump of the spraying machine, and a line that air-feeds the powder quick-setting agent from the other side through a confluence pipe installed in the middle. This is a construction method in which quick-setting shotcrete is sprayed onto the ground surface until it reaches a predetermined thickness.

Patent Document 1 discloses cement and plaster characterized by containing an acrylic polymer having a molecular weight of approximately 300,000 to 2,000,000 or a partial hydrolyzate thereof containing acrylic acid, methacrylic acid, their ester, or acrylamide as a structural unit. A dust preventive agent for spraying construction using a hydraulic inorganic binder such as the following has been disclosed.
Patent Document 2 describes a rebound reducing agent containing an alginate and a polyacrylate, an alginate and a polyacrylamide, a rebound reducing agent containing a polyacrylate, an quick setting agent, and the rebound reducing agent. A spraying material, a cement and a cement composition containing the spraying material, a quick-setting concrete containing cement and a quick-setting agent, and the rebound reducing agent are mixed at a spray nozzle and sprayed. The construction method is disclosed.

Japanese Unexamined Patent Publication No. 61-31335 Japanese Patent Application Publication No. 2001-261397

When using a spray method in which an quick-setting agent is mixed with concrete, the addition of the quick-setting agent increases the stickiness of the shotcrete, and it adheres to the pipes and nozzles of the spraying machine, reducing the amount of shotcrete discharged. The present inventor has discovered that there is a problem to be solved.

The present invention provides a hydraulic composition for spraying that can suppress adhesion to the pipes and nozzles of a spraying machine and maintain a high discharge force even if the spraying hydraulic composition is highly adhesive and contains an quick-setting agent. The present invention provides an agent for reducing adhesion to piping, a hydraulic composition for spraying, and a wet spraying method.

The present invention comprises (A) one or more monomers selected from acrylic acid or its salt, acrylic ester, methacrylic acid or its salt, methacrylic ester, and acrylamide, and has a weight average molecular weight of 20,000. Relating to an adhesion reducing agent for spraying hydraulic compositions to piping, including a polymer having a molecular weight of 6,500,000 or less (hereinafter referred to as component (A)) and a quick setting agent (B) (hereinafter referred to as component (B)) .

The present invention also relates to a sprayable hydraulic composition containing component (A), component (B), cement, water, and aggregate.

The present invention also provides a method for producing a hydraulic composition by mixing cement, water, and aggregate;
Mixing component (A) and component (B) in the hydraulic composition to produce a hydraulic composition for spraying,
Spraying the spraying hydraulic composition onto a target object;
Regarding wet spraying method.

According to the present invention, a hydraulic composition for spraying can suppress adhesion to the pipes and nozzles of a spraying machine, and can maintain a high discharge force even if the hydraulic composition for spraying is highly adhesive and contains an quick-setting agent. It is possible to provide an agent for reducing adhesion to pipes, a sprayable hydraulic composition, and a wet spraying method.

A schematic diagram of a spraying device used in Examples.

[Adhesion reducing agent for spraying hydraulic composition to piping]
<(A) component>
Component (A) of the present invention is one or more monomers (hereinafter referred to as monomers) selected from acrylic acid or its salt, acrylic ester, methacrylic acid or its salt, methacrylic ester, and acrylamide. (A1)) and has a weight average molecular weight of 20,000 to 6,500,000. Component (A) is a polymer containing the constituent monomer (A1).

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 acrylic esters include acrylic acid methyl ester, acrylic acid ethyl ester, acrylic acid propyl ester, acrylic acid butyl ester, acrylic acid hexyl ester, acrylic acid octyl ester, hydroxyethyl acrylate, 2-ethylhexyl acrylate, and acrylic acid. Examples include acid glycidyl esters.
Examples of methacrylic acid esters include methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, hexyl methacrylate, octyl methacrylate, hydroxyethyl methacrylate, 2-ethylhexyl methacrylate, and methacrylate. Examples include acid glycidyl esters.

The monomer (A1) is preferably one or more monomers selected from acrylic acid or a salt thereof, methacrylic acid or a salt thereof, and acrylamide; One or two types of monomers are more preferred, and acrylic acid or a salt thereof monomer is even more preferred.

The polymer of component (A) may contain a monomer other than monomer (A1) (hereinafter referred to as monomer (A2)).
As the monomer (A2), 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; and unsaturated carboxylic half esters such as monomethyl itaconate, monobutyl itaconate, and monoethyl maleate, unsaturated sulfonic acids such as vinylsulfonic acid, methallylsulfonic acid, 2-(meth)acrylamido-2-methylpropanesulfonic acid, and phosphorus. Unsaturated phosphoric acids such as acid-2-((meth)acryloyloxy)ethyl, hydrogen phosphate bis[2-((meth)acryloyloxy)ethyl], unsaturated phenols such as vinylphenol, ethylene, acrylonitrile and methacryloyl Cyanovinyl such as nitrile, vinyl formate, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl stearate, vinyl octylate, vinyl ester of aliphatic carboxylic acid having 3 to 18 carbon atoms such as vinyl neodecanoate, methyl vinyl ether, Vinyl ether monomers such as 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 methacrylamide, N-isopropylacrylamide, N-isopropylmethacrylamide, N- Examples include unsaturated amide compounds such as vinylpyrrolidone.

The proportion of monomer (A1) in all the monomers constituting component (A) is preferably 60 mol% or more, more preferably 70 mol% or more, still more preferably 80 mol% or more, even more preferably It is 90 mol% or more, and preferably 100 mol% or less, and may be 100 mol%.

From the viewpoint of preventing adhesion to piping and nozzles, component (A) is preferably one or more selected from polyacrylic acid or a salt thereof, polymethacrylic acid or a salt thereof, and polyacrylamide; and polyacrylamide are more preferred, and polyacrylic acid or a salt thereof is even more preferred.

The weight average molecular weight of component (A) is 20,000 or more, preferably 50,000 or more, more preferably 100,000 or more, still more preferably 200,000 or more, and 6,500,000 or less, preferably from the viewpoint of preventing adhesion to the nozzle. is 5 million or less, more preferably 3.5 million or less, even more preferably 2.5 million or less, even more preferably 2 million or less.

The weight average molecular weight of component (A) can also be determined by gel permeation chromatography under the following conditions using a mixed solvent of acetonitrile and water (phosphate buffer) as a developing solvent and polyethylene glycol as a standard substance.
Column: GMPWXL-GMPWXL (Anion) manufactured by Tosoh Corporation
Detector: Differential refractometer Eluent: 0.2M phosphate buffer/acetonitrile = 9/1
Standard product: polyethylene glycol equivalent (monodispersed polyethylene glycol with known molecular weight, molecular weight: 21000, 44200, 101000, 185000, 580000, 977000)
Conditions: Column temperature: 40°C, flow rate: 0.5 mL/min, concentration: 2 mg/mL

The agent for reducing adhesion to piping for spraying hydraulic compositions of the present invention preferably contains component (A) in an amount of 0.5% by mass or more, more preferably 1% by mass or more, from the viewpoint of preventing adhesion to piping and nozzles. , more preferably 2% by mass or more, preferably 20% by mass or less, more preferably 10% by mass or less, still more preferably 5% by mass or less.

<(B) component>
Component (B) of the present invention is an quick-setting agent. Examples of the quick-setting agent include one or more quick-setting agents selected from inorganic salt-based quick-setting agents, cement mineral-based quick-setting agents, and natural mineral-based quick-setting agents.
Examples of the inorganic salt rapid setting agent include alkali metal aluminates, alkali metal carbonates, aluminum sulfate, dihydrate gypsum, hemihydrate gypsum, anhydrite, calcium chloride and silicates, calcium hydroxide, and the like.
Examples of cement mineral quick-setting agents include calcium aluminate and calcium sulfoaluminate.
Examples of the natural mineral quick setting agent include calcined alum stone. A composite quick-setting agent that is a combination of a plurality of these can also be used.

Component (B) of the present invention is preferably a quick-setting agent containing aluminum as a constituent from the viewpoint of hardening concrete and preventing adhesion to piping and nozzles. Rapid setting agents containing aluminum include calcium aluminate, calcium sulfoaluminate, calcium aluminate, aluminum hydroxide, sodium aluminate, potassium aluminate, aluminum sulfate, gypsum dihydrate, aluminum chloride, potassium aluminum sulfate. , potassium alum, iron alum, and ammonium iron alum.
Component (B) is one type selected from calcium aluminate, calcium sulfoaluminate, aluminum sulfate, potassium aluminum sulfate, gypsum dihydrate, and aluminum hydroxide, from the viewpoint of hardening of concrete and prevention of adhesion to piping and nozzles. The above are preferred, one or more selected from calcium aluminate, calcium sulfoaluminate, and aluminum sulfate are more preferred, and one or more selected from calcium aluminate and aluminum sulfate is even more preferred.

The agent for reducing adhesion to piping for spraying hydraulic compositions of the present invention preferably contains component (B) in an amount of 80% by mass or more, more preferably 85% by mass, from the viewpoint of preventing adhesion to piping and nozzles and rapid setting. % or more, more preferably 90% by mass or more, and preferably 99% by mass or less, more preferably 98% by mass or less, still more preferably 97.5% by mass or less.

In the adhesion reducing agent for spraying hydraulic compositions to piping of the present invention, the mass ratio (B)/(A) of the content of component (A) and the content of component (B) is the From the viewpoints of adhesion prevention and rapid setting, it is preferably 3.5 or more, more preferably 7 or more, even more preferably 14 or more, and preferably 90 or less, more preferably 50 or less, still more preferably 40 or less.

The agent for reducing the adhesion of the sprayable hydraulic composition to piping of the present invention may contain water. The content of water in the adhesion reducing agent for piping for spraying hydraulic compositions of the present invention is preferably less than 45% by mass, and further 40% by mass or less, from the viewpoint of preventing adhesion to piping and nozzles. Furthermore, it is 35% by mass or less, furthermore, 30% by mass or less, furthermore, 25% by mass or less, furthermore, 20% by mass or less, furthermore, 15% by mass or less, furthermore, 10% by mass or less, and furthermore, 5% by mass or less. It is not more than 1% by mass, and further not more than 1% by mass. In another embodiment, the agent for reducing the adhesion of the sprayable hydraulic composition to piping of the present invention does not need to contain water.

The agent for reducing the adhesion of a hydraulic composition for spraying to piping of the present invention is effective in reducing the amount of the hydraulic composition for spraying adhering to piping. In the present invention, the piping includes the piping and nozzle of the line through which the spraying hydraulic composition is pneumatically fed by the pump of the spraying machine.

[Hydraulic composition for spraying]
The spraying hydraulic composition of the present invention contains component (A), component (B), cement, water, and aggregate.
In the sprayable hydraulic composition of the present invention, the components (A) and (B) are the same as those described in the adhesion reducing agent for pipes for sprayable hydraulic compositions of the present invention.
The hydraulic composition for spraying of the present invention can appropriately apply the embodiments described in the adhesion reducing agent to piping for hydraulic composition for spraying of the present invention.

As cement, there are various types of Portland cement such as normal, early strength, super early strength, low heat and medium heat, and various mixed cements made by mixing these Portland cements with fly ash, blast furnace slag, silica, fine limestone powder, etc. Can be mentioned. From the viewpoint of preventing adhesion to the nozzle, the cement is preferably ordinary Portland cement or early strength Portland cement.

Examples of the aggregate include aggregates selected from fine aggregates and coarse aggregates. The aggregate preferably includes fine aggregate. Examples of fine aggregate include those specified by number 2311 in JIS A0203-2014. Fine aggregates include river sand, land sand, mountain sand, sea sand, lime sand, silica sand, and their crushed sand, blast furnace slag fine aggregate, ferronickel slag fine aggregate, lightweight fine aggregate (artificial and natural), and recycled Examples include fine aggregate. Further, examples of coarse aggregate include those specified by number 2312 in JIS A0203-2014. For example, coarse aggregates include river gravel, land gravel, mountain gravel, sea gravel, lime gravel, crushed stones thereof, blast furnace slag coarse aggregate, ferronickel slag coarse aggregate, lightweight coarse aggregate (artificial and natural), and recycled Examples include coarse aggregate. Different types of fine aggregate and coarse aggregate may be used in combination, or a single type may be used.
The spraying hydraulic composition of the present invention preferably contains fine aggregate as the aggregate. The amount of fine aggregate used in the sprayable hydraulic composition of the present invention is preferably 800 kg/m ³ or more, more preferably 900 kg/m ^{3 or more, and preferably 1300 kg/m 3 or} less, more preferably 1200 kg/m 3 or more. m ³ or less.
In the sprayable hydraulic composition of the present invention, the fine aggregate ratio is preferably 35% or more, more preferably 45% or more, and preferably 70% or less, more preferably 65% or less. Here, the fine aggregate ratio is the volume content of fine aggregate in the total aggregate.

The spraying hydraulic composition of the present invention preferably has a water/cement ratio [mass percentage (mass %) of water and cement in the hydraulic composition] of 30 from the viewpoint of preventing adhesion to the nozzle and rapid setting. The content is at least 40% by mass, more preferably at least 50% by mass, and is preferably at most 80% by mass, more preferably at most 70% by mass, even more preferably at most 65% by mass.

In the spraying hydraulic composition of the present invention, component (A) is preferably 0.02 parts by mass or more, more preferably 0.05 parts by mass, based on 100 parts by mass of cement, from the viewpoint of preventing adhesion to piping and nozzles. It is contained in an amount of at least 0.1 parts by mass, more preferably at least 0.1 parts by mass, and preferably at most 2 parts by mass, more preferably at most 1 part by mass, and still more preferably at most 0.5 parts by mass.

In the sprayable hydraulic composition of the present invention, component (B) is preferably 4 parts by mass or more, more preferably 6 parts by mass, based on 100 parts by mass of cement, from the viewpoint of preventing adhesion to piping and nozzles and rapid setting. The content is at least 7 parts by mass, more preferably at least 7 parts by mass, and preferably at most 12 parts by mass, more preferably at most 11 parts by mass, even more preferably at most 10 parts by mass.

In the sprayable hydraulic composition of the present invention, the mass ratio (B)/(A) of the content of component (A) and the content of component (B) is determined to prevent adhesion to piping and nozzles and to prevent rapid setting. From this point of view, it is preferably 3.5 or more, more preferably 7 or more, even more preferably 14 or more, and preferably 90 or less, more preferably 50 or less, still more preferably 40 or less.

The spraying hydraulic composition of the present invention may optionally contain a high-performance water-reducing agent, a high-performance AE water-reducing agent, a water-reducing agent including an AE water-reducing agent and a fluidizing agent, an expanding agent, a hardening accelerator, a hardening retardant, and cement. The composition may contain one or more of the following: polymers, foaming agents, waterproofing agents, rust preventives, shrinkage reducing agents, pigments, fibers, water repellents, anti-efflorescence agents, and the like.

[Wet spraying method]
The present invention produces a hydraulic composition by mixing cement, water, and aggregate,
Mixing component (A) and component (B) in the hydraulic composition to produce a hydraulic composition for spraying,
Spraying the spraying hydraulic composition onto a target object;
It is a wet spraying method.
In the wet spraying method of the present invention, the components (A) and (B) are the same as those described in the adhesion reducing agent for pipes for spraying hydraulic compositions of the present invention.
In the wet spraying method of the present invention, the cement and aggregate are the same as those described in the hydraulic composition for spraying of the present invention.
In the wet spraying method of the present invention, the embodiments described in connection with the adhesion reducing agent for the spraying hydraulic composition to piping and the spraying hydraulic composition of the present invention can be applied as appropriate.

In the wet spraying method of the present invention, first, cement, water, and aggregate are mixed to produce a hydraulic composition.
A hydraulic composition manufactured by mixing cement, water, and aggregate has a water/cement ratio [mass percentage (mass%) of water and cement in the hydraulic composition] that prevents adhesion to the nozzle. From the viewpoint of rapid setting, it is preferably 30% by mass or more, more preferably 40% by mass or more, even more preferably 50% by mass or more, and preferably 80% by mass or less, more preferably 70% by mass or less, and Preferably it is 65% by mass or less. Typically, the water/cement ratio of the hydraulic composition is reflected in the subsequently manufactured sprayable hydraulic composition. Therefore, in the present invention, the water/cement ratio of the spraying hydraulic composition is preferably within the above range.

In the present invention, cement, water, and aggregate can be mixed by a known method. Specifically, there is a method of mixing cement, water, and aggregate at the same time. For mixing these components, a mixing mixer such as a pan-type forced mixer, a two-shaft forced mixer, a tilting mixer, etc. can be used.

In the present invention, a hydraulic composition for spraying is manufactured by adding components (A) and (B) to a hydraulic composition obtained by mixing cement, water, and aggregate. The hydraulic composition, components (A), and components (B) can be mixed by, for example, a common wet spraying method in which concrete, components (A), and components (B) are separately conveyed under air pressure and mixed together. It can be carried out with Moreover, it is preferable that the (A) component and the (B) component are mixed in advance and mixed with the hydraulic composition. The mixture of component (A) and component (B) may be an adhesion reducing agent for piping for the sprayable hydraulic composition of the present invention.

In the present invention, component (A) is preferably 0.02 parts by mass or more, more preferably 0.02 parts by mass or more, from the viewpoint of preventing adhesion to piping and nozzles, based on 100 parts by mass of cement in the hydraulic composition. 0.5 parts by mass or more, more preferably 0.1 parts by mass or more, and preferably 2 parts by mass or less, more preferably 1 part by mass or less, still more preferably 0.5 parts by mass or less.

In the present invention, the component (B) is preferably 4 parts by mass or more, more preferably 4 parts by mass or more, based on 100 parts by mass of cement in the hydraulic composition, from the viewpoint of preventing adhesion to piping and nozzles and rapid setting. The content is 6 parts by mass or more, more preferably 7 parts by mass or more, and preferably 12 parts by mass or less, more preferably 11 parts by mass or less, still more preferably 10 parts by mass or less.

In the present invention, the mass ratio (B)/(A) of the (A) component and (B) component, and the mixing amount of the (A) component and the mixing amount of the (B) component, is determined to prevent adhesion to piping and nozzles. From the viewpoint of rapid setting, it is preferably 3.5 or more, more preferably 7 or more, even more preferably 14 or more, and preferably 90 or less, more preferably 50 or less, still more preferably 40 or less.

In the spraying method of the present invention, the thus prepared hydraulic composition for spraying is sprayed onto an object. This method corresponds to the so-called wet spraying method.
The wet spraying method of the present invention can be carried out using conventional spraying equipment. The spraying equipment may be used as long as it can perform wet spraying without any trouble. For example, a device such as "Arriba 280" (trade name) manufactured by Ariba Co., Ltd. may be used to pressure-feed the hydraulic composition, and the (A) component and (B) component may be used. It is possible to use a product such as "Natomcrete" manufactured by Chiyoda Seisakusho Co., Ltd. under pressure to convey the mixture, and to mix the two to prepare a hydraulic composition for spraying, which can then be sprayed.

The following components were used in the table.
<(A) component>
(A-1): Polyacrylic acid, manufactured by Fuji Film Wako Pure Chemical Industries, Ltd., weight average molecular weight 80,000
(A-2): Polyacrylic acid, Jurimer AC-10LHPK, manufactured by Toagosei Co., Ltd., weight average molecular weight 2,000,000
(A-3): Polyacrylic acid, manufactured by Fuji Film Wako Pure Chemical Industries, Ltd., weight average molecular weight 1,800,000
(A-4): Sodium polyacrylate, Acofloc A-190, manufactured by MT Aqua Polymer Co., Ltd., weight average molecular weight 6,300,000
<(A') component (comparison component of (A) component)>
(A'-1): Polyacrylic acid, manufactured by Fuji Film Wako Pure Chemical Industries, Ltd., weight average molecular weight 18,000
(A'-2): Sodium polyacrylate, Aron A-20P-X, manufactured by Toagosei Co., Ltd., weight average molecular weight 7,300,000
<(B) component>
(B-1): Calcium aluminate, cement mineral quick-setting agent, Taiheiyo Shot Master, manufactured by Taiheiyo Materials (B-2): Calcium hydroxide, manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.

(1) Preparation of mortar The ingredients of mortar are as follows.
Water: Tap water Cement: A 1:1 mixture by weight of ordinary Portland cement manufactured by Taiheiyo Cement Co., Ltd. and ordinary Portland cement manufactured by Sumitomo Osaka Cement Sand: Mountain sand from Joyo City, Kyoto Prefecture Surface dry state Specific gravity 2.55
Gravel: Crushed stone from Ieshima, dry surface, specific gravity 2.77

A mortar mixer specified in "JIS R 5201 Physical Test Methods for Cement" was used to prepare the mortar.
240 g of water was put into the mixing bowl of a mortar mixer, and then 400 g of cement was added and stirred at low speed for 30 seconds. After that, 1054 g of sand was added and stirred again at low speed for 2 minutes to prepare mortar. 725 g of gravel was added to the obtained mortar and stirred by hand until it became homogeneous. 40 g of the obtained concrete and a mixture of component (A) or component (A') in the table and component (B) in the amount shown in the table (amount based on 100 parts by mass of cement) were sprayed as shown in Figure 1. I poured it into the concrete inlet of the device, covered the inlet with my hand, opened the valve, and sprayed it onto the plywood. The series of steps from pouring a mixture of this concrete, component (A) or component (A'), and component (B) in advance to spraying was repeated 10 times.
The concrete inlet and nozzle were made using stainless steel (SUS304) piping (nominal diameter (A): 20). Further, the discharge pressure was adjusted to 0.5 MPa using a pressure regulator. The compressor used was Toscon GP-4T8 (manufactured by Toshiba Corporation).

(2) Evaluation The following evaluations were performed using the obtained spray mortar. The results are shown in Table 1.

(2-1) Nozzle survival rate The amount of concrete remaining in the nozzle is the amount of concrete remaining in the nozzle, excluding the amount of concrete discharged outside the nozzle (the amount that adhered to the wall, the amount that rebounded, and the amount that dripped from the nozzle) from the amount of concrete that was put in. It was recorded as a quantity. The amount of concrete remaining in the nozzle relative to the amount of concrete thrown in was defined as the nozzle survival rate. The results are shown in Table 1.

Claims (7)

(A) polyacrylic acid or its salt having a weight average molecular weight of 20,000 to 6,500,000 (hereinafter referred to as component (A)), (B) quick setting agent (hereinafter referred to as component (B)), cement, water, and aggregate, the content of component (B) is 7 parts by mass or more and 12 parts by mass or less per 100 parts by mass of cement, and the mass of the content of component (A) and the content of component (B) is A hydraulic composition for spraying, wherein the ratio (B)/(A) is 3.5 or more and 90 or less. The spraying hydraulic composition according to claim 1 , wherein component (B) is an quick setting agent containing aluminum as a constituent component. The spraying hydraulic composition according to claim 1 or 2 , wherein the content of component (A) is 0.02 parts by mass or more and 2 parts by mass or less based on 100 parts by mass of cement. Produce a hydraulic composition by mixing cement, water and aggregate,
In the hydraulic composition, (A) polyacrylic acid or a salt thereof having a weight average molecular weight of 20,000 to 6,500,000 (hereinafter referred to as component (A)), and (B) an quick setting agent (hereinafter referred to as (B)). The mixing amount of component (B) is 7 parts by mass or more and 12 parts by mass or less per 100 parts by mass of cement, and the mass ratio of the mixing amount of component (A) and the mixing amount of component (B) ( B) / (A) is mixed so that it is 3.5 or more and 90 or less to produce a hydraulic composition for spraying,
Spraying the spraying hydraulic composition onto a target object;
Wet spraying method. 5. The wet spraying method according to claim 4 , wherein component (B) is a rapid setting agent containing aluminum as a constituent component. The wet spraying method according to claim 4 or 5 , wherein the component (A) is mixed into the hydraulic composition in an amount of 0.02 parts by mass or more and 2 parts by mass or less based on 100 parts by mass of cement. The wet spraying method according to any one of claims 4 to 6 , wherein a mixture of components (A) and (B) is mixed into the hydraulic composition.

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