JP2003321263A - Spraying material and spraying construction method using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a spraying material which effects such advantages that a dust generation amount can be lessened, construction cost can be reduced because of reduced rebound, and a quick setting spraying cement concrete excellent in durability can be obtained in an environment susceptible to underground water, or the like, and also to provide a spraying construction method using the same. <P>SOLUTION: The spraying material comprises a cement concrete in which a fly ash is compounded in the cement, particularly in an amount of 10-100 pts. based on 100 pts. cement, and a liquid quick setting agent containing the elements of aluminum, sulfur and fluorine, an alkanolamine and the group 4A elements according to needs. The spraying construction method comprises using the spraying material, or comprises pressure-feeding the cement concrete and the quick setting agent individually, making confluent and mixing to spray. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention, for example, in the construction of an underground tank for storing oil or LPG in an underground cavern, sprays it on an exposed ground surface, and further, in an environment susceptible to the influence of groundwater or the like. And a spraying material excellent in durability and a spraying method using the same. The cement concrete of the present invention is a general term for cement paste, mortar, and concrete. Further, parts and% in the present invention are based on mass unless otherwise specified.

[0002]

2. Description of the Related Art Conventionally, in order to prevent collapse of exposed ground such as tunnel excavation, a quick-setting concrete spraying method in which a quick-setting agent is mixed with concrete has been performed.
(Japanese Patent Publication No. 60-4149). This method is usually used to prepare sprayed concrete at a cement, aggregate and water metering and mixing plant installed at an excavation site, transport it with an agitator car, pump it with a concrete pump, and join a joint pipe installed on the way. Then, it is a method of mixing with a quick-setting agent sent from the other side and spraying it as quick-setting shotcrete on the ground surface to a predetermined thickness.

On the other hand, oil and LPG are contained in the underground tank of oil and LPG under the sea surface by a water-sealing method, but groundwater may pass through sprayed concrete and flow into the tank from the bedrock side. At this time, calcium in calcium hydroxide eluted from the cement concrete reacts with carbon dioxide in the air to generate calcium carbonate, which adheres to the blades and pipes of the pump when carrying out petroleum or LPG and causes failure. Therefore, cement concrete that produces a small amount of calcium hydroxide is required.

Further, as a quick-setting agent which has been conventionally used as a spraying material, calcium aluminate, a mixture of alkali metal aluminate and alkali carbonate, and the like,
In addition, a mixture of calcium aluminate, an alkali metal aluminate, an alkali carbonate, and the like, a mixture of calcium aluminate and 3CaO / SiO _2, and the like are known.
(See JP-A-64-051351, JP-B-56-27457, JP-A-61-026538, and JP-A-63-210050).

These quick-setting agents have the function of promoting the setting of cement, and both are mixed with cement concrete and sprayed on the ground surface. And, the method of adding these quick-setting agents is usually a method in which the amount of dust increases due to powder mixing by pneumatic transportation. Therefore, the workability may be deteriorated by wearing protective glasses or dust masks when spraying, and a construction method with a smaller amount of dust has been required especially in the construction work of the underground cavity.

As a method for producing a small amount of dust, a method is proposed in which a quick-setting agent is slurried and added to cement concrete, and then mixed, and then a solution of an alkali metal aluminate is separately pressure-fed, mixed, and sprayed. Has been
(See JP-A-5-139804). However, since this method uses a highly alkaline liquid, it is difficult to handle, and protective glasses, gloves, etc. are required at the time of spraying, and there is a problem that workability deteriorates.

On the other hand, there has been proposed a quick-setting construction method for improving workability by making a quick-setting agent into a slurry and mixing alum with cement concrete (Japanese Patent Laid-Open No. 05-097491). reference). However, in recent years, in order to further improve workability and shorten the construction period, there has been a demand for further improvement in quick setting property and strength development property.

As a result of various studies on the above-mentioned problems and requirements, the present inventor has completed the present invention by finding that the above-mentioned problems can be solved by spraying using a specific spray material. Came to.

[0009]

That is, the present invention provides cement concrete prepared by mixing cement and fly ash, and a liquid quick-setting admixture containing aluminum element, sulfur element, elemental fluorine, and alkanolamine. A spraying material containing, cement concrete is 100 parts of cement, the spraying material is a mixture of 10 to 100 parts of fly ash, a liquid quick-setting agent,
Furthermore, it is the spraying material containing a 4A group element, and is a spraying construction method in which the cement concrete and the liquid quick-setting admixture are separately pumped, combined and mixed, and sprayed, in constructing an underground cavity, A spraying method using the spraying material.

[0010]

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

Examples of the cement used in the present invention include various types of portland cement such as ordinary, early strength, moderate heat, and super early strength which are commercially available, mixed cement of blast furnace cement and limestone cement, and the like. It is also possible to use it in the form of fine powder.

In the present invention, cement and fly ash are used together to reduce the amount of calcium hydroxide produced from cement concrete.

The fly ash used in the present invention is a kind of artificial pozzolanic substance which is obtained by collecting fine particles of ash contained in waste gas from a pulverized coal combustion boiler with a dust collector or the like. The particle size of fly ash is not particularly limited, but it is preferably 2000 cm ² / g or more in terms of Blaine specific surface area. If it is less than 2000 cm ² / g, the pozzolanic reactivity is poor, and the strength development and the effect of suppressing the amount of calcium hydroxide produced may be reduced. The amount of fly ash used is 10-100 parts for 100 parts of cement, 20-80
Parts are preferred. If it is less than 10 parts, the strength may not be improved and the effect of suppressing the amount of calcium hydroxide produced may not be obtained, and if it exceeds 100 parts, the viscosity of the cement concrete may be increased and the workability may be deteriorated.

In the present invention, if necessary, cement concrete may be added to a set retarder, an AE agent, a water reducing agent, a fluidizing agent, a thickening agent, a water retention agent, a waterproofing agent, a foaming agent, a foaming agent, methyl cellulose and the like. Mixtures such as anti-separation agents, rust preventives, polymer emulsions and silica fume, and one or more additives such as fibrous substances such as organic fibers, glass fibers, carbon fibers and steel fibers. It is possible to use them together in a range that does not impair the object of the invention.

The cement concrete used in the present invention contains cement and aggregate. Here, as the aggregate, one having a low water absorption rate and a high aggregate strength is preferable. The maximum size of the aggregate is not particularly limited as long as it can be sprayed. As fine aggregate, river sand, mountain sand, lime sand,
And silica sand can be used, and as coarse aggregate, river gravel, mountain gravel, lime gravel, and the like can be used.

From the viewpoint of strength development, the amount of water used for cement concrete is preferably 35 parts or more, and more preferably 40 to 60 parts, relative to 100 parts of cement. If it is less than 35 parts, cement concrete may not be sufficiently mixed.

In the present invention, a quick-setting spray-cement concrete is prepared by mixing a liquid quick-setting agent with the spray-cement concrete containing the cement concrete.

The liquid accelerator used in the present invention contains aluminum element, sulfur element, fluorine element and alkanolamine.

The feed material for the aluminum element is not particularly limited, and examples thereof include aluminum sulfate, aluminate, other inorganic aluminum compounds, organic aluminum compounds, and aluminum complexes. Examples of the aluminum sulfate include sodium alum, potassium alum, ammonium alum, aluminum hydroxysulfate, and aluminum sulfate.
Examples of the aluminate include lithium aluminate, sodium aluminate, potassium aluminate, calcium aluminate, and magnesium aluminate. Other inorganic aluminum compounds include bauxite, aluminum oxide, aluminum hydroxide, aluminum chloride. , Aluminum phosphate, aluminum nitrate, aluminum fluoride, polyaluminum chloride, aluminum carbonate hydroxide, synthetic hydrotalcite, and aluminum metasilicate. In the present invention, one kind or two or more kinds of these aluminum element feed materials can be used, and in the present invention, it is preferable to use aluminum sulfate which also serves as a sulfur element feed material.

The elemental sulfur feed material is not particularly limited, but in addition to elemental sulfur such as sulfur and sulfur flower, sulfide, sulfuric acid or its salt, sulfurous acid or its salt, thiosulfuric acid or Examples thereof include salts thereof and organic sulfur compounds. Examples of sulfides include magnesium sulfide, calcium sulfide, iron sulfide, and phosphorus pentasulfide,
Examples of the sulfates include aniline sulfate, aluminum sulfate, ammonium sulfate, magnesium sulfate, manganese sulfate, barium sulfate, calcium sulfate, sodium alum, potassium alum, ammonium alum, and hydroxylamine sulfate, and sulfites include hydrogen sulfite. Examples thereof include ammonium and calcium sulfite, and examples of the thiosulfate include ammonium thiosulfate and barium thiosulfate. In the present invention, one or more of these sulfur element feedstocks can be used,
Highly soluble in water, low in manufacturing cost, and from the viewpoint of excellent setting properties, use of sulfuric acid or a salt thereof is preferable,
The use of ammonium alum is more preferred.

Further, the feed material of the elemental fluorine is not particularly limited, and examples thereof include organic fluorine compounds, fluoride salts, fluorosilicic acid salts, boron fluoride salts, and hexafluorophosphate salts. Examples of the organic fluorine compound include fluorinate and CFCs, examples of the fluoride salt include aluminum fluoride, ammonium fluoride, and calcium fluoride, and examples of the silicofluoride salt include ammonium silicofluoride and silicofluoride. Examples of the boron fluoride include boron fluoride, boron trifluoride, boron trifluoride monoethylamine complex, boron trifluoride acetic acid complex, ferrous borofluoride, and ammonium borofluoride. Examples of the hexafluorophosphate include hexafluorophosphate, salts of hexafluorophosphate, ammonium hexafluorophosphate, and the like. In the present invention, one or two or more of these elemental fluorine feed materials can be used, which is highly safe, has a low manufacturing cost, and is excellent in the coagulation property, and therefore a fluoride salt,
The use of silicofluorides and borofluorides is preferred.

The alkanolamine of the present invention has the structural formula N-
It is an organic compound having an R-OH structure. Here, R is usually an atomic group called an alkyl group or an allyl group,
For example, a linear alkyl group such as a methylene group, an ethylene group, and an n-propylene group, an alkyl group having a branched structure such as an isopropyl group, and an allyl group having an aromatic ring such as a phenyl group and a benzyl group. Is mentioned.
R may be bonded to the nitrogen atom at two or more positions, and part or all of R may have a cyclic structure. Further, R may be bonded to a plurality of hydroxyl groups, and part of the alkyl group may contain elements other than carbon and hydrogen, such as sulfur, fluorine, chlorine, and oxygen. Examples of such alkanolamines include ethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N, N-dimethylethanolamine, N, N-
Examples thereof include dibutylethanolamine, N- (2-aminoethyl) ethanolamine, boron trifluoride triethanolamine, and derivatives thereof. In the present invention, one or more of these alkanolamines can be used, and among them, diethanolamine, N, N-dimethylethanolamine, and the use of a mixture thereof are preferable, and diethanolamine and N, N-dimethyl are preferable. More preferred is the use of a mixture of ethanolamines.

The proportions of elemental aluminum, elemental sulfur, elemental fluorine and alkanolamine in the liquid quick-setting admixture are
Aluminum element is Al for 100 parts of SO ₃ converted sulfur
25 to 110 parts in terms of ₂ O ₃ , 2.5 to 50 in terms of elemental fluorine
Parts, and 1 to 50 parts of alkanolamine are preferred. Outside this range, the quick-setting property may be significantly reduced, or the viscosity of the liquid may be high and pumping may be difficult.

In the present invention, in addition to aluminum element, sulfur element, fluorine element, and alkanolamine,
It is preferable to use a liquid quick-setting agent containing a Group 4A element from the viewpoint of improving the adhesive properties of quick-setting spray-cement concrete under a low temperature environment.

Here, the group 4A element is titanium, zirconium, hafnium or the like, and the feed materials for these are not particularly limited, but water-soluble elements of group 4A such as titanium, zirconium and hafnium. It is preferable to include one or more compounds. As a raw material for supplying a water-soluble compound of titanium, titanium sulfate, titanyl sulfate, titanium chloride, titanium hydroxide, titanium carbonate, titanium fluoride, titanium bromide, titanium iodide, titanium borate, alkoxy titaniums,
And titanium compounds such as titanium acylates. Further, as the feedstock of the water-soluble compound of zirconium, zirconium sulfate, zirconyl sulfate, zirconium chloride, zirconium hydroxide, zirconium nitrate,
Zirconium compounds such as zirconium fluoride, zirconium bromide, zirconium iodide, zirconium dichloride, and zirconium borate are included. further,
Examples of the raw material for supplying the water-soluble compound of hafnium include hafnium compounds such as hafnium dichloride oxide and hafnium fluoride. In the present invention, one or two or more of these Group 4A element compounds can be used. Further, even if the group 4A element compound of the present invention is a compound that reacts with water, it is possible to use a compound that is dispersed in water in the form of a polymer gel or colloid after the reaction. Of these, compounds containing titanium and / or zirconium, which are easily available, have good solubility in water, and are economical, are preferable, and titanium sulfate and titanyl sulfate are most preferable.

The liquid quick-setting admixture of the present invention is a group consisting of aluminum element, sulfur element, fluorine element, alkanolamine, and 4A group elements, alkali metal elements such as lithium, sodium, and potassium, and silicon. Those containing one or more elements selected from the above can also be used. Further, the liquid quick-setting admixture can improve the quick-setting property by being heated to 40 ° C. or higher and admixed with cement concrete.

The amount of the liquid quick-setting agent used is preferably 5 to 15 parts, more preferably 7 to 10 parts, based on 100 parts of cement. If it is less than 5 parts, it may be difficult to accelerate the initial setting of the quick-setting spray-cement concrete in which the cement concrete and the liquid quick-setting admixture are mixed. If it exceeds 15 parts, the strength development will be good, but it is economically preferable. Absent.

In the spraying method using the liquid quick-setting admixture of the present invention, conventionally used spraying equipment can be used.
Specifically, for example, the product name "Alibar 285" manufactured by Aliber Co., Ltd. is used as the air pressure delivery system for the pressure-fed cement concrete, the Shintech piston pump, etc. For pumping binder, piston pump, flanger pump, gear pump,
A squeeze pump and the like can be used.

As the spraying method using the cement concrete of the present invention and the liquid quick-setting admixture, various spraying methods can be used depending on the required physical properties, economy, workability and the like. As the spraying method of the present invention, either a wet spraying method or a dry spraying method can be used, but from the viewpoint of dust reduction, water is added to the cement concrete side in advance before mixing the liquid quick-setting admixture. It is preferable to use a wet spraying method in which kneading is performed. In the case of the wet spraying method, the concrete consistency is preferably 20 to 70 cm as the flow value when the slump cone is pulled out when pumping with a concrete pump.
In the case of the air pressure feeding method such as 285, it is preferable that the slump is 5 cm or more. As the wet spraying method, for example, a liquid in which cement, fine aggregate, coarse aggregate, and water are added, kneaded, pneumatically fed, and pressure-fed by a quick-setting agent supply device from one of the Y-shaped tubes provided in the middle. Examples include a method of spray-mixing a quick-setting spray-cement concrete by mixing and mixing quick-set agents.

In the spraying method using the liquid quick-setting admixture of the present invention, the spraying pressure is preferably 0.2 to 0.5 MPa and the spraying speed is preferably 4 to 20 m ³ / h.

Further, the pressure of the pressure-fed air for feeding the liquid quick-setting admixture is 0.01 to 0.3 MPa from the pressure-feeding pressure of the cement concrete so that the inside of the pressure-fed pipe is not clogged when the cement concrete is mixed in the liquid quick-placing agent. It is preferably large.

In the spraying method using the liquid quick-setting admixture of the present invention, the time from the mixing of the liquid quick-setting admixture with the sprayed cement concrete to the discharge of the quick-set sprayed cement concrete is within 5 seconds. Is preferred.

[0033]

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

Experimental Example 1 Cement, fly ash, and W / C in the amounts shown in Table 1 were used. The fly ash was used as a fine aggregate in a fine aggregate ratio of 60%. On the other hand, concrete is prepared by mixing 1 part of a water reducing agent, and cement 100
Liquid quick-setting admixture A was mixed at a ratio of 10 parts to 10 parts, and
The compressive strength of 28 days was measured. The environmental temperature of the test was 20 ° C. The results are also shown in Table 1. In addition, the calcium hydroxide of the cement paste mixed with the liquid quick-setting admixture A in the same manner except that the fine aggregate and the coarse aggregate were aged 28 days was quantified. The results are shown in Table 1.
Also described in.

<Materials used> Cement a: ordinary Portland cement, commercial product, Blaine value 3,200 cm ² / g, density 3.16 Cement b: blast furnace cement type B, commercial product, Blaine value 3,
700 cm ² / g, density 3.04 Fly ash: commercial product, Blaine value 5,500 cm ² / g, density
2.40 Fine aggregate: River sand from Himekawa, Itoigawa City, Niigata Prefecture, surface dryness, density 2.
62 Coarse aggregate: Crushed stone from Himekawa, Itoigawa City, Niigata Prefecture, surface dryness, density 2.
64, maximum dimension 13mm Water reducing agent: High-performance water reducing agent, commercial product, polyethylene glycol liquid quick-setting agent A: Aluminum hydroxide, aluminum sulfate octahydrate, sulfuric acid, calcium fluoride, and triethanolamine (TEA) are used. , A liquid quick-setting admixture containing Al ₂ O ₃ 12%, SO ₃ 20%, fluorine 4%, and TEA 2%

<Measurement method> Compressive strength: Measured according to JIS A 1132 and JIS A 1108 Calcium hydroxide: Kneaded with cement paste according to JIS R 5201, sealed in a vinyl bag and aged for 28 days Then hydrate with acetone, dry, finely pulverize, and quantify with a thermal analyzer (TG-DTA) from the dehydration peak near 430 ° C.

[0037]

[Table 1]

[0038] Experimental Example 2 Cement b360kg / m ^3, fine aggregates 1,000kg / m ^3, and W / C = 55.6
10% fly ash as a percentage of fine aggregate
Mortar was prepared by blending 8 kg / m ³ . The same procedure as in Experimental Example 1 was carried out except that the liquid quick-setting admixture shown in Table 2 was mixed with 100 parts of the cement in the prepared mortar and the setting start time was measured. The environmental temperature of the test was 20 ° C. The results are also shown in Table 2.

<Materials used> Liquid quick-setting admixture B: aluminum hydroxide, aluminum sulfate octahydrate, sulfuric acid, cryolite, diethanolamine and precipitated silica, Al ₂ O ₃ 12%, SO ₃ 20%, Na ₂ O 4
%, Fluorine 4%, silicon 2%, and diethanolamine
Liquid quick-setting admixture containing 0.5% Liquid quick-setting admixture C: Aluminum hydroxide, aluminum sulfate octahydrate, sulfuric acid, sodium silicofluoride, monoethanolamine, precipitating silica, and titanyl sulfate, Al
₂ O ₃ 12%, SO ₃ 20%, Na ₂ O 4%, Fluorine 4%, Silicon 2
%, Titanium 2%, and Monoethanolamine 4%

<Measurement method> Setting time: The initial time is measured according to the Society of Civil Engineers standard “Quality standard for quick-setting concrete for shotcrete (JSCED-102)”

[0041]

[Table 2]

Experimental Example 3 The unit amount of each material was cement b 450 kg / m ³ , fine aggregate 922 kg /
m ³ , coarse aggregate 691 kg / m ³ , water 200 kg / m ³ , and water reducing agent 5 kg / m ³
Then, the fly ash shown in Table 3 was mixed to prepare concrete, and this concrete was pumped by a piston pump under the conditions of a spraying speed of 10 m ³ / h, and a Y-shape installed 3 m behind the spraying nozzle tip. Air was inserted by a pipe and air was conveyed at a spraying pressure of 0.4 MPa. On the other hand, the liquid quick-setting admixture was mixed with 100 parts of cement b at a position 50 cm behind the tip of the spray nozzle so as to be 10 parts. This liquid quick-setting agent,
The rebound rate and the amount of dust were measured by mixing with the sprayed concrete that was pressure-fed from the other side of the Y-shaped pipe to obtain quick-setting sprayed concrete. The environmental temperature of the test was 20 ° C.
The results are shown in Table 3. Further, similarly to Experimental Example 1, calcium hydroxide was quantified by removing fine aggregate and coarse aggregate from the shotcrete of 28 days old. The results are also shown in Table 3. In addition,
For comparison, 1 part of the powder quick-setting admixture was added to 1 part of cement b.
The same experiment was carried out by mixing so as to be 0 part. The results are also shown in Table 3.

<Material used> Powder quick-setting agent: calcium aluminate-based quick-setting agent, commercial product

<Measurement method> Rebound rate: A quick-setting shotcrete was made into an arch shape with an iron plate at a pumping speed of 10 m ³ / h for 6 minutes, and the height was 4.5.
It sprayed on a m, 5.5 m wide tunnel. After that, (rebound rate) = (mass of quick-setting sprayed concrete that dropped without adhering to the simulated tunnel) / (mass of quick-setting sprayed concrete sprayed at the simulated tunnel) x 100 (%) Dust amount: Quick-setting shotcrete is sprayed into the simulated tunnel at a pumping speed of 10 m ³ / h for 6 minutes, during which the dust amount is measured at a fixed position of 3 m from the spraying site.

[0045]

[Table 3]

[0046] The unit amount of Example 4 each material, cement b450kg / m ^3, fly ash 105 kg / m ^3, fine aggregates 922 kg / m ^3, coarse aggregate 691kg / m ^3, water 200k
g / m ^3, and a concrete prepared as a water-reducing agent 5 kg / m ^3, was confirmed adhesion state at the time of spraying the wall surface in an environment temperature of 5 ° C.. The concrete pump is a squeeze pump, and it is pressure-fed at a spraying speed of 4 m ³ / h, and air is inserted at a spraying pressure of 0.4 MPa by inserting air with a Y-tube installed 3 m behind the spraying nozzle tip. did. On the other hand, the liquid quick-setting admixture was mixed with 100 parts of cement b at a position 50 cm behind the tip of the spray nozzle so as to be 10 parts. The liquid quick-setting admixture used is one in which the titanium content of the liquid quick-setting admixture C is changed. The results are also shown in Table 4.

<Measurement method> Adhesion at low temperature: After spraying on the wall surface of the simulated tunnel, the presence or absence of deformation was visually confirmed. The case where no deformation was observed after spraying was marked with ⊚, the case where there was some sagging but there was no problem in practical use was marked with ◯, and the case where there was obvious sagging and the spray material could not be used was marked with Δ.

[0048]

[Table 4]

[0049]

EFFECT OF THE INVENTION By using the spray material of the present invention, the amount of dust generated can be reduced, and the rebound of quick-setting spray-cement concrete can be reduced to reduce the construction cost. The effect is to obtain a quick-setting shotcrete concrete with excellent durability in an environment that is easily affected by.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C04B 22/14 C04B 22/14 A 24/12 24/12 E21D 11/10 E21D 11 / 10D // E21D 13/00 13/00 C04B 103: 12 C04B 103: 12 (72) Inventor Minoru Morioka 2209 Aomi, Aomi-cho, Nishikubiki-gun, Niigata Prefecture Inside the Aomi factory of Electric Chemical Industry Co., Ltd. 2209 Aomi, Aomi-cho Aomi, Aomi Factory, Denki Kagaku Kogyo Co., Ltd. (reference) 2D055 AA10 DB00 KA00 LA10 4G012 PA27 PB02 PB15 PB20 PC06 PC11 PE04

Claims (5)

[Claims] 1. A spray material containing cement concrete prepared by mixing cement and fly ash, and a liquid quick-setting admixture containing aluminum element, sulfur element, elemental fluorine and alkanolamine. 2. The cement concrete is cement 100.
The spray material according to claim 1, wherein 10 to 100 parts of fly ash is blended with respect to 1 part. 3. The spray material according to claim 2 or 3, wherein the liquid quick-setting admixture further contains a Group 4A element. 4. The cement concrete according to claim 1 or 2 and the liquid quick-setting admixture according to claim 1 or 3 are separately pressure-fed, combined and mixed and sprayed. Spraying method. 5. When constructing an underground cavity, claim 1.
A spraying method comprising using the spraying material according to any one of items 1 to 3.