JP2003112956A - Rapid hardening agent for spraying, rapid hardening cement concrete and spraying method using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a rapid hardening agent for spraying which attains the compatibility of a pumping property with prevention of sags, has excellent developability of strength and permits trowel finishing, and rapid hardening cement concrete, and to provide a spraying method for slopes. SOLUTION: The rapid hardening agent for spraying contains a group 4A compound and an alkali thickening type polymer emulsion and the rapid hardening cement concrete contains cement concrete. The rapid hardening cement concrete solves the contradicting problems of the pumpability and the sags and is efficiently sprayed to slopes to reinforce the slopes, by which the improvement in working efficiency and the assurance of the beauty of the slopes by finishing after the construction are made possible.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a highway, a dam,
In addition, on steep slopes, etc., in order to prevent the slopes (hereinafter referred to as "slopes") formed by cutting and embankment from collapsing, cement concrete (a generic term for paste, mortar, and concrete) is sprayed directly on the slopes. Used in the construction method and the construction method of spraying cement concrete on the frame skeleton arranged in a lattice pattern or a cross girder pattern, a rapid-hardening agent for spraying, rapid-hardening cement concrete, a spraying method of rapid-hardening cement concrete, and rapid-hardening cement concrete The method of spraying on the slope.

[0002]

2. Description of the Related Art If the slope is left unattended, collapse such as erosion and landslide will occur due to natural weathering, heavy rain, etc. Therefore, it is necessary to carry out protection to prevent collapse. As a method to prevent collapse of the slope, a method of spraying cement concrete directly on the slope and a method of fixing a formwork made of reinforcing material such as reinforcing bars and steel frames with anchors on the slope, spraying cement concrete and reinforced concrete A method of forming a frame is used (see Japanese Patent Publication No. 58-58493). Recently, there is an increasing demand for a free frame construction method in which a reinforcing material that can be deformed without shaping or cutting can be directly placed on the slope.

As cement concrete used for such slope collapse prevention work, slump is conventionally 5c.
Hard-mixed cement concrete of m or less was prepared on site in small batches and sprayed so as not to cause sagging.

[0004]

However, in this method, since the flowability of cement concrete is small and the pumpability by the pump is poor, the construction efficiency is as low as less than 2 m ³ / hr, and it takes labor to mix the materials. However, there was a problem that the cost would be high.

Therefore, the spraying speed is increased and a large amount of cement is supplied from the ready-mixed plant to the cement concrete by using an agitator car or a freight car to improve the construction efficiency, reduce manpower, and shorten the construction period to reduce the cost. It is possible.

In order to increase the spraying speed, it is necessary to increase the fluidity (slump value) of the cement concrete to improve the pumpability. However, if the fluidity is large, the cement concrete will drip off the slope after spraying. There were challenges.

When the viscosity of cement concrete is increased to reduce the fluidity in order to solve this problem, the pumpability of the cement is lowered and the spraying speed is lowered.

In order to solve the conflicting problem of fluidity with respect to cement concrete, a method of increasing the viscosity of cement concrete can be considered. As a method of increasing the viscosity immediately after spraying, for example, when using a calcium aluminate-based rapid hardening agent at the time of spraying, it is possible to prevent the cement concrete from slipping off, but the hardening of the sprayed cement concrete is fast. There was a problem that the ironing could not be done and the sprayed surface could not be corrected.

As described above, the rapid hardening cement is capable of solving the contradictory problems of the spraying speed and the deformation after spraying, and securing the working time (finishing working time) for maintaining the viscosity range to the extent that the iron finishing can be performed. There was a need for concrete and spray hardeners.

[0010]

Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, the inventor has found that the above-mentioned problems can be solved by using a specific hardener for spraying. As a result, the present invention has been completed.

That is, the present invention is a spray hardening agent containing a water-soluble compound of a 4A group element and an alkali thickening type polymer emulsion, wherein the 4A group element is titanium or zirconium. The rapid-hardening agent for spraying characterized by the above, and the rapid-hardening agent for spraying further containing water.

A rapid-hardening cement concrete containing the spray-hardening agent and cement concrete, and a rapid-hardening cement concrete containing a non-hydraulic powder, containing fibers. The rapid-hardening cement concrete.

Further, the present invention is a spraying construction method characterized in that the rapid hardening agent for spraying is pressure-fed and mixed and mixed with cement concrete, and a reinforcing material is arranged on a slope to form a frame skeleton. After being formed, the rapid hardening cement concrete is sprayed onto the frame skeleton to construct a frame, which is a slope spraying method.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.

The quick-hardening agent for spraying used in the present invention contains a water-soluble compound of a Group 4A element and an alkali thickening type polymer emulsion.

The rapid hardening cement concrete used in the present invention contains a rapid hardening agent for spraying and cement concrete.

The water-soluble compound of the 4A group element used in the present invention promotes setting by mixing with cement concrete, and shortens the time from once spraying to again spraying on the same slope. This is something that can be done, and it is possible to secure a finishing work time that allows iron finishing. If a water-soluble compound of the 4A group element is not used, slipping may occur when spraying on the same slope again in a short time.

Examples of the water-soluble compound of the 4A group element (hereinafter referred to as 4A group compound) used in the present invention include water-soluble compounds such as titanium, zirconium and hafnium, and they can be used in solid or liquid form. However, in terms of dust reduction and mixability, a liquid form such as an aqueous solution or suspension is preferable.

Specific examples thereof include water-soluble titanium compounds such as titanium sulfate, titanium chloride, titanium hydroxide, titanium carbonate, titanium fluoride, titanium bromide, titanium iodide, and titanium borate.

Examples of water-soluble zirconium compounds include zirconium sulfate, zirconium chloride, zirconium hydroxide, zirconium nitrate, zirconium fluoride, zirconium bromide, zirconium iodide, zirconium dichloride, and zirconium borate. .

Examples of the water-soluble hafnium compound include hafnium dichloride oxide, hafnium fluoride and the like, or an aqueous solution thereof, and one or more of these can be used.

The method of dissolving these compounds is not particularly limited, and they can be dissolved in water under neutral, acidic, or alkaline conditions or under appropriate conditions such as room temperature or under heating. Further, the aqueous solution in the present invention also includes a suspension having a saturated solubility or higher.

Among the above Group 4A compounds, a water-soluble titanium compound or a water-soluble zirconium compound is preferable from the viewpoint of easy availability and economy.

On the other hand, even a compound containing a Group 4A element, an oxide such as titanium dioxide or zirconium dioxide, a nitride such as titanium nitride or zirconium nitride,
Alternatively, an insoluble compound typified by a carbide such as titanium carbide or zirconium carbide cannot obtain a coagulation promoting effect.

The Group 4A element mainly forms trivalent and tetravalent compounds, but a tetravalent compound is preferable because it has an excellent effect of promoting coagulation.

As specific examples thereof, tetravalent titanium sulfate, tetravalent titanium chloride, tetravalent zirconium sulfate,
And tetravalent zirconium chloride, etc., and it is preferable to use one or two or more of these, because they are easily available and do not contain chlorine and can be used for reinforced concrete. Because of the advantages of
It is more preferable to use tetravalent titanium sulfate.
Further, the form of dissolution of tetravalent titanium sulfate in an aqueous solution is not particularly defined, and the mass ratio of TiO ₂ / SO ₃ is not particularly defined, but the mass ratio of TiO ₂ / SO ₃ is 0.3-2. The degree is preferable from the viewpoint of stability of the solution.

The concentration of the ingredient in the 4A group compound aqueous solution is not particularly limited, but is preferably 5 to 60% by mass.
-50 mass% is more preferred. If it is less than 5% by mass, the strength development of the rapid hardening cement concrete may not be extended, and if it exceeds 60% by mass, the pumpability may be deteriorated.

The amount of Group 4A compound used is 100% cement.
With respect to parts by mass, 0.5 to 6 parts by mass in terms of component (anhydrous) is preferable, and 1 to 4 parts by mass is more preferable. If it is less than 0.5 parts by mass, the effect of preventing sag of the rapid hardening cement concrete is small, additional blowing may not be possible and initial strength development may not be extended, and if it exceeds 6 parts by mass, the hardening of the rapid hardening cement concrete may be set. However, there is a possibility that the time required for iron finishing cannot be secured due to excessive acceleration, the pumpability is lowered, and the strength development is not extended.

The alkali-thickening type polymer emulsion (hereinafter, simply referred to as polymer emulsion) used in the present invention is a polymer emulsion that thickens in an alkaline atmosphere to lose the fluidity of cement concrete,
By mixing with cement concrete, the viscosity of the cement concrete is instantly increased, and sagging of the rapid hardening cement concrete during spraying is prevented.

The polymer emulsion is obtained by copolymerizing an unsaturated carboxylic acid and an ethylenically unsaturated compound in water or an organic solvent.

The unsaturated carboxylic acids include acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, citraconic acid, aconitic acid, and unsaturated carboxylic acids or salts thereof such as crotonic acid, maleic anhydride or anhydrous. Unsaturated carboxylic acid anhydrides such as citraconic acid or salts thereof, and monomethyl itaconate, monobutyl itaconate,
And unsaturated carboxylic acid half-esters such as monoethyl maleate or salts thereof. Examples of the salts include water-soluble salts such as alkali metal salts, alkaline earth metal salts, ammonium salts, amine salts, and pyridine derivative salts.

These unsaturated carboxylic acids can be used either individually or in combination of two or more, and the blending ratio thereof is not particularly limited. Among these, acrylic compounds, methacrylic compounds, acrylate compounds, or carboxylic acid derivatives of methacrylate compounds are preferable, and acrylic acid, methacrylic acid, or salts thereof are most preferable, from the viewpoint of showing more excellent effects.

Examples of ethylenically unsaturated compounds copolymerizable with unsaturated carboxylic acids include (1) ethylene, (2) styrene, (3) ethylenically unsaturated alcohols such as allyl alcohol, and (4) hydroxyethyl (meth). ) Acrylate, hydroxypropyl (meth) acrylate, diethylene glycol (meth) acrylate, dipropylene glycol (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, ethylene glycol di (meth) acrylate, etc. (Meth) acrylic acid alkyl ester monomer having a hydroxyl group, (5) (meth) acrylonitrile nitrile group-containing monomer, (6) methyl (meth) acrylate, ethyl (meth) acrylate,
Butyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth)
Having an alkyl group having about 1 to 22 carbon atoms such as acrylate and glycidyl (meth) acrylate (meth)
C3 such as acrylic acid alkyl ester monomer, (7) vinyl formate, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl caproate, vinyl caprylate, vinyl laurate, vinyl stearate, vinyl octylate, and vinyl neodecanoate. To about 18 aliphatic vinyl carboxylic acid esters, (8) vinyl aromatic carboxylic acid monomers such as vinyl benzoate, (9) vinyl ether monomers such as methyl vinyl ether, butyl vinyl ether, and phenyl vinyl ether, (10) (meth)
Amide-based monomers having an amide group such as acrylamide, N, N-methylenebis (meth) acrylamide, and N-vinylpyrrolidone, (11) vinylsulfonic acid, allylsulfonic acid, vinyltoluenesulfonic acid, styrenesulfonic acid, 2-acrylamide A monomer having a sulfonic acid group such as 2-methylpropanesulfonic acid, sulfopropyl (meth) acrylate, and 2-hydroxy-3- (meth) acryloyloxypropylsulfonic acid;
(12) Maleimide-based monomers such as maleimide, N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-phenylmaleimide, and N-toluylmaleimide, and (13) halogenated olefin monomers such as vinyl chloride and vinylidene chloride. , (14) triallyl cyanurate, triallyl isocyanurate, trimethylolpropane trimethacrylate, allyl acrylate,
And polyfunctional vinyl monomers such as allyl methacrylate, (15) N-vinylpyrrolidone, and (16) divinylbenzene.

Further, these alkali metal salts, alkaline earth metal salts, ammonium salts, amine salts, pyridine derivative salts and the like can be used. These ethylenically unsaturated compounds may be used alone or in combination of two or more, and the mixing ratio thereof is not particularly limited.

Among the ethylenically unsaturated compounds, an acrylic compound or a methacrylic compound is preferable, and an acrylic acid ester monomer or a methacrylic acid ester monomer is most preferable, from the viewpoint of exhibiting a more excellent thickening effect.

The mixing ratio of the unsaturated carboxylic acid and the ethylenically unsaturated compound is not particularly limited, but is preferably 95: 5 to 5:95 in terms of molar ratio.

As the polymer of the polymer emulsion of the present invention, a combination of ethylene compounds having a carboxyl group, for example, an acrylic compound is selected as an unsaturated carboxylic acid, and an acrylic compound is also selected as an ethylenically unsaturated compound and polymerized. A combination of homopolymers of compounds is also possible. The same applies to homopolymers of methacrylic compounds and other ethylene compounds containing a carboxyl group.

A known method can be used as a method for polymerizing the polymer emulsion, and although not particularly limited, unsaturated carboxylic acids and an ethylenically unsaturated compound may be used.
Examples thereof include emulsion polymerization, suspension polymerization, solution polymerization, and bulk polymerization.

During the polymerization of the polymer emulsion, for example, a polymerization initiator, a known redox catalyst or other polymerization catalyst,
Chain transfer agents as well as surfactants can be used.

As the polymerization initiator, organic peroxides such as benzoyl peroxide, ammonium peroxide, potassium peroxide, sodium peroxide, hydrogen peroxide, perborate,
In addition, known ones such as inorganic peroxides such as persulfate can be used.

In the case of emulsion polymerization, known emulsifiers can be used. For example, sodium alkylbenzene PEO (polyethylene oxide) sulfonate, polyacrylic acid, polyethylene glycol, methyl cellulose, hydroxy cellulose, and polyvinyl alcohol (PV
A) etc. are mentioned.

Further, chain transfer agents such as acetaldehyde, carbon tetrachloride, dodecyl mercaptan, hexadecyl mecarcaptan, and 2-mercaptoethanol for the purpose of controlling the molecular weight, persulfates, hydrogen peroxide, benzoyl peroxide, Polymerization catalysts such as azobisisobutyronitrile and known redox catalysts can be used alone or as a mixture. Further, at the time of polymerization, a known anionic surfactant,
Cationic surfactants, nonionic surfactants, and polyethylene glycol (PEG) -based surfactants can be used.

The molecular weight of the polymer component contained in the polymer emulsion is not particularly limited, but a weight average molecular weight of 1,000 or more is preferable in order to reduce the sag of the sprayed concrete.

The polymer emulsion is usually used in the form of an aqueous dispersion, and if necessary, an antifreezing agent, a binder, a pigment, a dispersant, a polyol compound, a pH adjusting agent, a film-forming auxiliary agent, an antioxidant, an antiseptic agent. , A water resistant agent, a defoaming agent, a lubricant, a wetting agent, and the like can be contained.

Examples of the antifreezing agent include ethyl glycol, butyl glycol, ethylene glycol, propylene glycol, butylene glycol, polyethylene glycol, polypropylene glycol, ethyldiglycol, butyldiglycol, glycerin, propionylcarbinol, and mixtures thereof. Is mentioned. In the present invention, it is preferable to use ethylene glycol because it is inexpensively available.

As the binder, a conventional synthetic or natural polymer latex is used. For example, styrene /
Butadiene type copolymer, styrene / acrylic type copolymer, vinyl acetate / acrylic type copolymer, ethylene / vinyl acetate type copolymer, butadiene / methyl methacrylate type copolymer, vinyl acetate / butyl acrylate type copolymer , Styrene / maleic anhydride copolymer, isobutene / maleic anhydride copolymer, acrylic acid / methyl methacrylate copolymer, oxidized starch, esterified starch, etherified starch, enzyme modified starch, casein, soybean protein , And mixtures thereof.

Examples of pigments include clay, titanium oxide, calcium carbonate, kaolin, clay, lake, silica, ferrite, satin white, gypsum, barium sulfate, aluminum hydroxide, zinc oxide, synthetic plastics, and mixtures thereof. Can be mentioned.

Examples of the dispersant include sodium polyacrylate, sodium pyrophosphate, sodium hexametaphosphate, and mixtures thereof.

Examples of the polyol compound include alkylene glycols such as ethylene glycol and propylene glycol, glycerin, other polyhydric alcohols, and mixtures thereof.

Examples of the pH adjusting agent include hydroxides of alkali metals and alkaline earth metals such as sodium hydroxide and calcium hydroxide, ammonia, amines, pyridine derivatives, and mixtures thereof.

Examples of the film-forming aid include butyl cellosolve, butyl carbitol, acetate, and mixtures thereof.

The concentration of components in the polymer emulsion is not particularly limited, but is preferably 0.5 to 80% by mass, more preferably 2 to 20% by mass. If it is less than 0.5% by mass, the thickening effect may be small, and if it exceeds 80% by mass, production of the polymer emulsion may be technically difficult and stability may be impaired.

The amount of the polymer emulsion used is preferably 0.01 to 7 parts by mass, more preferably 0.05 to 3 parts by mass in terms of the components, relative to 100 parts by mass of cement.
If it is less than 0.01 parts by mass, the thickening effect is not recognized and sagging or skin peeling may occur, so the effect of preventing slipping off of the rapid hardening cement concrete may be small, and if it exceeds 7 parts by mass, sagging or sagging may occur. Skin peeling may occur, additional blowing may not be possible, and strength development may be impaired.

According to the present invention, in order to suppress the separation of the paste from the rapid hardening cement concrete and to improve the pumpability and the strength development of the rapid hardening cement concrete, bone and typified by sand and gravel widely used for concrete materials. In addition to the material, it is preferable to use non-hydraulic powder.

The non-hydraulic powder used in the present invention includes
Examples thereof include silica fume, fly ash, bentonite, calcium carbonate, slowly cooled slag, and metakaolin. Among these, silica fume is preferable because it has a great effect of improving the pumpability and strength development of cement concrete.

The specific surface area of the non-hydraulic powder is preferably 1,500 cm ² / g or more by the Blaine method, and 2000
cm ² / g or more is more preferable. If it is less than 1500 cm ² / g, the separation of the paste from the rapid hardening cement concrete cannot be suppressed, and the pumpability and strength development of the rapid hardening cement concrete may be reduced.

The amount of non-hydraulic powder used is 100% cement.
The amount is preferably 3 to 50 parts by mass, more preferably 5 to 30 parts by mass. If it is less than 3 parts by mass, the paste may be separated from the rapid-hardening cement concrete and the strength development may be reduced, and if it exceeds 50 parts by mass, the viscosity of the cement concrete may be increased and pumpability may be deteriorated.

Further, in the present invention, it is preferable to use fibers from the viewpoint of improving impact resistance and elasticity of the rapid hardening cement concrete.

The fiber used in the present invention may be either inorganic or organic. Examples of the inorganic fiber include glass fiber, carbon fiber, rock wool, asbestos, ceramic fiber, and metal fiber. Further, as the organic fiber, vinylon fiber, polyethylene fiber, polypropylene fiber, polyacrylic fiber, cellulose fiber, polyvinyl alcohol fiber, polyamide fiber, pulp,
Examples include hemp, wood wool, and wood chips. Among these,
From the viewpoint of economy, metal fibers and vinylon fibers are preferable.

The length of the fiber is 5 in terms of pumpability and mixing property.
It is preferably 0 mm or less, more preferably 5 to 30 mm.
If it exceeds 50 mm, the rapid hardening cement concrete may be clogged in the pipe during pumping.

The amount of the fiber used is preferably 0.1 to 3 parts by volume, more preferably 0.4 to 1.5 parts by volume, in 100 parts by volume of the concrete containing no spray-hardening agent. 0.1
If it is less than the capacity part, the effect of improving impact resistance and elasticity may be small, and if it exceeds 3 parts by volume, the pumping property may be deteriorated, which may be uneconomical.

Further, in the present invention, it is preferable to use a water reducing agent from the viewpoint of improving the adhesion of the rapid hardening cement concrete. The water-reducing agent can be added to either or both of the cement-concrete side and the spray-hardening agent side, and is not limited, but it is preferably added to the cement-concrete side.

Examples of the water reducing agent used in the present invention include naphthalene sulfonic acid formalin condensate, melamine sulfonic acid formalin condensate, and polycarboxylic acid type polymer compound. Among these, polycarboxylic acid-based polymer compounds are preferable because they are unlikely to affect the initial setting property and strength development.

The cement used in the present invention is JI
Various portland cements specified by S R 5210, various mixed cements specified by JIS R 5211, JIS R 5212, and JIS R 5213, blast furnace cement prepared by the above-mentioned admixture mixing ratio specified by JIS, and fry Examples include ash cement, silica cement, and filler cement mixed with limestone powder and the like.

The fine aggregate ratio of the aggregate used in the present invention and the maximum size of the aggregate are not particularly limited as long as they can be sprayed. Since strength is required to prevent the slope from collapsing, a material having high aggregate strength is preferable. From the viewpoint of maintaining fluidity, those having a low water absorption rate are preferable. In order to prevent salt damage or alkali-aggregate reaction, the aggregate preferably has a low content of chlorine and alkali metal elements.

As the fine aggregate, river sand, mountain sand, lime sand, silica sand, etc. can be used, and as the coarse aggregate, river gravel, mountain gravel, lime gravel, etc. can be used.

In the present invention, in addition to the above materials and aggregates such as sand and gravel, an AE agent and a set retarder can be used in combination within a range that does not substantially impair the object of the present invention.

In the spraying method used in the present invention,
Conventionally used spraying equipment, for example, trade names "Denka NATM Cleats", "Den Kanato Mickman",
"Denkanatomic TL additive machine" (above manufactured by Denki Kagaku Kogyo Co., Ltd.), concrete pumping machine "Aliver 280" (manufactured by Aliver Co., Ltd.) and the like can be used.

As the spraying method used in the present invention, various known spraying methods, such as the NATM method, can be used according to the required physical properties, economy, workability and the like.

For example, cement, water, fine aggregate, coarse aggregate if necessary, and a kneading agent to which a water reducing agent and the like are added and kneaded, and the mixture is air-fed using a pressure-feeding hose, and in the middle of the pressure-feeding hose. A wet spraying method in which a Y-shaped pipe is provided, and a rapid hardening agent for spraying is pneumatically fed from one of the Y-shaped tubes, and the mixture and mixture are sprayed as rapid hardening cement concrete can be mentioned.

The pumping amount (construction efficiency) is 0.5 m ³ /
preferably less than ^{10m 3 / hr hr, 2m 3} / hr or more 4m ³ / hr or less is more preferable. Pumping amount is 0.5m ³
If it is less than / hr, the work efficiency is reduced and the pumping amount is 10
If it exceeds m ³ / hr, the output limit of the commercially available compressor that can be used at the work site is exceeded. Also, pumping rate 2m ³ / h
If it is less than r, there is no difference from the prior art, and if it exceeds 4 m ³ / hr of pumping amount, the pulsation of the hose becomes large and the construction may become difficult.

As a method for mixing the rapid-hardening agent for spraying with cement concrete, a rapid-hardening agent for spraying, cement, non-hydraulic powder, and fine aggregate are mixed in advance with a mixing device such as a mixer, and then a bag is prepared. It is possible to use a conventionally known method such as a method of packing and bringing it to the site and making it into a slurry at the site, but use a shower ring that allows the rapid hardening agent for spraying to enter uniformly and forcibly, and It is preferred to mix the hardener with the cement concrete by co-mixing with the spray-pressure air.

Here, the 4A group compound and the polymer emulsion may be separately pressed into the cement concrete, or a mixture of the 4A group compound and the polymer emulsion may be pressed into the cement concrete.

When the group 4A compound and the polymer emulsion are separately pressed into the cement concrete, the mixing order is not particularly limited, but the group 4A compound is first mixed into the cement concrete, and then the polymer emulsion is mixed. The method is preferable in that the rapid hardening agent for spraying can be uniformly dispersed in the cement concrete.

When the Group 4A compound and the polymer emulsion are preliminarily mixed immediately before press-fitting, it is preferable to shorten the time period from the mixing of the Group 4A compound and the polymer emulsion until the press-fitting into cement concrete within 3 seconds. If it exceeds 3 seconds, the polymer emulsion may deteriorate and the desired thickening effect may not be obtained.

The mounting position of the Y-shaped tube in the pressure-feeding hose is 0.1 to 100 m before the discharge port in terms of mixing property and pressure-feeding property.
Is preferable, and 3-20 m is more preferable. If it is less than 0.1 m, the rapid hardening cement concrete may drip, and if it exceeds 100 m, the pressure-feeding hose may be blocked.

As the slope spraying method of the present invention, rapid-hardening cement concrete, which is a mixture of spray-hardening agent and cement concrete, may be sprayed directly on the slope.
In order to increase the reinforcing effect, it is preferable to dispose a reinforcing material to form a frame skeleton, drive an anchor, and then spray a rapid hardening cement concrete on it. As the frame, a free frame construction method in which a deformable reinforcing material is arranged is more preferable.

Here, the reinforcing material is a wire, a wire mesh, a metal such as a reinforcing bar or a steel frame, polypropylene, polyethylene,
It is composed of polyvinyl alcohol, polyamide, resins such as acrylic resin, glass fiber, carbon fiber and the like. These are combined to form a frame skeleton, and rapid-hardening cement concrete is sprayed to form a frame.

The method of arranging the reinforcing material used in the free frame construction method is not particularly limited, but the following method may be mentioned, for example. First, corrugated reinforcing bars φ1 to 3 m
Two wire meshes each having a width of 30 to 60 cm and a length of 1 to 3 m are arranged in parallel with each other in the longitudinal direction along the slope at the same distance as the width of the wire mesh. Then, stand in parallel 2
A frame skeleton is formed using a spacer such as a reinforcing bar on a wire mesh. When extending the frame skeleton vertically and horizontally, it is preferable to drive an anchor at this intersection. Further, it is also possible to use a frame skeleton for intersections at the intersections of this frame skeleton.

The frame skeleton thus arranged is sprayed by using the rapid hardening cement concrete, and the cement concrete is re-sprayed to the exposed portion of the frame skeleton reinforcing material, or a trowel, spatula or roller is used. It is possible to maintain the aesthetics of the frame by finishing with, etc., and at the same time, in order to match with the slope shape other than the spraying part, uneven with a spatula to reproduce the shape of the rock, etc.
Slope rework is also possible.

The rapid hardening cement concrete used on the slope has a unit cement amount of 270 to 600 kg / m ³ , W
The C / C ratio (water / cement ratio) is preferably 35 to 65 mass% and the s / a ratio (fine aggregate ratio) is preferably 50 to 100 mass%, and the compressive strength after 4 weeks of age is 18 N / mm. It is preferably ² or more.

[0082]

The present invention will be described in detail below based on experimental examples.

Experimental Example 1 Unit cement amount 430 kg / m ³ , non-hydraulic powder 50 k
g / m ³ , W / C (water / cement ratio) = 48% by weight, and s / a (fine aggregate ratio) = 70% by weight, and 1 part by volume of fiber Concrete was prepared by mixing. This concrete is concrete pumping machine Aliver 280 type (made by Aliver)
Was pneumatically fed at a feed rate of 4 m ³ / hr and a feed pressure of 0.4 MPa.

In the preparation of concrete, the amount of water reducing agent used was adjusted so that the slump was about 20 cm.

Then, with respect to 100 parts of cement, the amounts of the group 4A compound and the polymer emulsion in the amounts shown in Table 1 in terms of the components were pumped by a pump, and together with the air to be pumped from a Y-tube attached 10 m before the discharge port. It was pressed into concrete, mixed, and sprayed as quick-hardening concrete.

With respect to the obtained quick-hardening concrete, additional blowing, workability, pumpability and compressive strength were measured. The results are also shown in Table 1.

<Material used> Cement: ordinary Portland cement, specific gravity 3.16 non-hydraulic powder A: silica fume, specific surface area 20000
0 cm ² / g, specific gravity 2.20 Fiber a: Steel fiber, 30 mm, specific gravity 7.85 Fine aggregate: Sand from Himekawa, Niigata Prefecture, specific gravity 2.62, FM value 2.8
6 Coarse aggregate: gravel from Himekawa, Niigata, specific gravity 2.63 Water reducing agent: polycarboxylic acid type high-performance water reducing agent, liquid Group 4A compound a: aqueous solution of titanyl sulfate, component concentration 20 mass% Polymer emulsion i: ethyl acrylate / methacryl Polymer emulsion containing acid copolymer (molar ratio 45/55), component concentration 10% by mass

<Measurement Method> Re-blowing: A frame skeleton having a width of 30 cm and a thickness of 30 cm was crossed in a cross shape and arranged on the slope. The rapid-hardening concrete was sprayed onto the frame skeleton, and 10 minutes later, the rapid-hardening concrete was again sprayed with a thickness of 15 cm, and the state of the additional spraying was confirmed. The case where 50% by mass or more of the increased blown portion collapsed was marked with X, the case where a portion of the increased blown portion collapsed was marked with Δ, and the case where none was seen was marked with ○.

Workability: A quick-hardening concrete was sprayed onto a frame skeleton having a width of 10 cm, a length of 40 cm and a thickness of 10 cm, and allowed to stand for 5 minutes, and the surface of the mold was flattened by a trowel. The workability of the iron leveling when flattening was evaluated. The case where it could be easily finished was marked with ◯, the case where it required a force to finish was marked with Δ, and the case where it could not be finished even with a force was marked with x.

Pumpability: When rapid-hardening concrete was pumped, when the pressure in the pump tube was 0.40 to 0.55 MPa, it was designated as ◯, and the inside of the pump tube was easily blocked 0.60.
When the pressure becomes 0.40 to 0.55 MPa by impacting the pressure-feeding pipe with a hammer even when the pressure is higher than or equal to MPa, the value is Δ.
The case where it did not become 40 to 0.55 MPa was marked with x.

Compressive strength: Five rapid-curing concrete specimens each having a diameter of 10 cm and a height of 20 cm were prepared and measured with a pressure resistance machine to obtain an average value.

[0092]

[Table 1]

Experimental Example 2 4A shown in Table 2 in terms of components with respect to 100 parts of cement
The same procedure as in Experimental Example 1 was performed except that 3 parts of the group compound and 1 part of the polymer emulsion were used to measure sagging, additional blowing, workability, and pumpability. The results are also shown in Table 2.

<Materials used> Group 4A compound b: zirconium sulfate aqueous solution, component concentration 2
0 mass% Group 4A compound c: titanium trichloride aqueous solution, component concentration 20
Mass% 4A group compound d: a mixture of 50 parts of 4A group compound aqueous solution and 50 parts of 4A group compound aqueous solution b 4A group compound e: hafnium sulfate aqueous solution, component concentration 20% by mass

<Measurement Method> Sagging: A 30 cm wide × 30 cm thick sloped form was crossed in a cross shape and placed on the sloped face. After that, spraying a quick-hardening concrete onto the slope formwork and observing, when there is a lot of sagging or skin loss, it is marked with X, when it is slightly seen, it is marked with Δ,
The case where it was not observed at all was marked as ○.

[0096]

[Table 2]

Experimental Example 3 Group 4A compound 3 in terms of components based on 100 parts of cement
The same procedure as in Experimental Example 1 was carried out except that sag and additional blowing were measured by using the polymer emulsion in the amounts shown in Table 3 and Table 3. The results are also shown in Table 3.

[0098]

[Table 3]

Experimental Example 4 100 parts of cement were converted into the group 4A compound a by component conversion
The same procedure as in Experimental Example 1 was performed except that 3 parts and 1 part of the polymer emulsion shown in Table 4 were used to measure sagging, additional blowing, workability, and pumpability. The results are also shown in Table 4.

<Materials Used> Polymer emulsion ii: Polymer emulsion containing a maleic anhydride / methyl methacrylate copolymer (molar ratio 40/60), copolymer component concentration 10% by weight Polymer emulsion iii: sodium acrylate /
Polymer emulsion containing hydroxyethyl acrylate copolymer (molar ratio 40/60), copolymer component concentration 10% by weight Polymer emulsion iv: Polymer emulsion containing ethyl acrylate / methacrylic acid / diethyl maleate copolymer (mol 40/40/20), copolymer component concentration 10% by mass Polymer emulsion v: Polymer emulsion containing a copolymer of 2-ethylhexyl acrylate / methacrylic acid / butyl acrylate (molar ratio 20/50/3
0), copolymer component concentration 10% by weight polymer emulsion vi: polymer emulsion containing a copolymer of methacrylamide / acrylic acid / ethyl methacrylate (molar ratio 20/50/30), copolymer component concentration 10% by weight polymer Emulsion vii: Polymer emulsion containing a copolymer of vinyl acetate / ethyl acrylate / acrylic acid / 2-ethylhexyl acrylate (molar ratio 5 /
5/50/40), copolymer component concentration 10% by mass

[0101]

[Table 4]

Experimental Example 5 The same procedure as in Experimental Example 1 was carried out except that the amount of non-hydraulic powder shown in Table 5 was used for 100 parts of cement, and the presence or absence of paste separation, the pumpability and the compressive strength were measured. It was The results are also shown in Table 5.

<Materials used> Non-hydraulic powder B: fly ash, specific surface area 4200c
m ² / g, specific gravity 2.25 non-hydraulic powder C: limestone fine powder, specific surface area 4000 cm
² / g, specific gravity 2.70 non-hydraulic powder D: bentonite, specific surface area 3600 cm
² / g, specific gravity 2.62

<Measurement method> Presence or absence of paste separation: The state of the rapid hardening concrete discharged from the nozzle was observed. When the separation of the cement paste in the quick-hardening concrete was not observed, it was evaluated as ○,
The case where the cement paste was found to be slightly separated was marked with Δ, and the case where the cement paste in the rapid hardening concrete was separated and flowed down from the nozzle was marked with x. Compressive strength: 10 cm in diameter per rapid hardening concrete
20 test pieces each having a height of 20 cm were prepared and measured with a pressure resistance machine. On the next day (1st day), the 7th day and the 28th day of kneading, 5 pieces each were measured and the average value thereof was obtained.

[0105]

[Table 5]

Experimental Example 6 The experiment was carried out in the same manner as in Experimental Example 1 except that the impact resistance and the pumping property were measured using the fibers of the capacity parts shown in Table 6 in 100 capacity parts of concrete. The results are also shown in Table 6.

<Material used> Fiber a: Commercial product, vinylon fiber, 25 mm, specific gravity 1.3
1 Fiber C: Commercial product, polyethylene fiber, 20 mm, specific gravity 0.93

<Measurement method> Impact resistance: A quick-hardening concrete after 1 hour of age is used with a width of 20.
cm x length 20 cm x thickness 1 cm
Placed on leveled standard sand, a sphere weighing 100 g was dropped from a height of 50 cm. If the product is destroyed within 5 drops, it is marked with △.
Those that did not crack without cracking were rated as ◯.

[0109]

[Table 6]

[0110]

EFFECTS OF THE INVENTION By using the rapid-hardening agent for spraying of the present invention, it is possible to prevent the rapid-hardening cement concrete immediately after spraying from slipping and slipping off the slope, and good pumpability and strength development, and Since it is possible to secure a finishing work time with a viscosity that allows iron finishing, it is possible to maintain the aesthetic appearance of the slope surface.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C04B 22/12 C04B 22/12 22/14 22/14 A 28/00 28/00 E02D 17/20 104 E02D 17/20 104Z // E02B 7/06 E02B 7/06 (C04B 28/00 C04B 22:06 Z 22:06 22:08 B 22:08 22:10 22:10 22:12 22:12 22:14 A 22:14 22:08 Z 22:08 24:26 24:26 22:06 A 22:06 18:08 Z 18:08 14:10 Z 14:10 14:28 14:28 18:14 18:14 14 : 48 A 14:48 14:42 Z 14:42 16:06 A 16:06 B) 111: 00 111: 00 (72) Inventor Kenji Yamamoto 2209 Aomi, Aomi-cho, Aomi-cho, Nishikubiki-gun, Niigata Prefecture Inside the Aomi Plant (72) Inventor Mitsuo Takahashi 2209 Aomi, Aomi-cho, Nishikubiki-gun, Niigata Prefecture A-term inside the Aomi Plant, Denki Kagaku Kogyo Co., Ltd. (reference) 2D044 DC03 4G012 MA00 MB04 M B06 MB08 MB12 MC01 MC11 PA06 PA10 PA15 PA24 PA27 PA29 PB03 PB04 PB07 PB08 PB09 PB10 PB27 PC04 PC08 PC11 PC12 PE04

Claims (8)

[Claims] 1. A quick-hardening agent for spraying containing a water-soluble compound of a Group 4A element and an alkali-thickening type polymer emulsion. 2. The rapid-hardening agent for spraying according to claim 1, wherein the Group 4A element is titanium or zirconium. 3. The method according to claim 1, which contains water.
The rapid-hardening agent for spraying described. 4. A quick-hardening cement concrete containing the quick-hardening agent for spraying according to any one of claims 1 to 3 and cement concrete. 5. The rapid hardening cement concrete according to claim 4, which contains a non-hydraulic powder. 6. The rapid hardening cement concrete according to claim 4 or 5, which contains fibers. 7. A spraying method characterized in that the rapid hardening agent for spraying according to any one of claims 1 to 3 is pressure-fed, mixed and mixed with cement concrete and sprayed. 8. A frame is constructed by arranging a reinforcing material on a slope to form a frame skeleton, and then spraying the rapid hardening cement concrete according to claim 4 onto the frame skeleton. Slope spraying method characterized by becoming.