JP2021160989A - Quick-hardening mortar composition - Google Patents

Abstract

To provide a quick-hardening mortar composition which is stably kept over a long period of time, has high initial strength, and can obtain a hardening body suppressing generation of white spots.SOLUTION: A quick-hardening mortar composition includes a quick-hardening admixture, cement and a fine aggregate. The quick-hardening admixture includes calcium aluminate, anhydrous gypsum, inorganic carbonate, hydroxycarboxylic acid, and alum. In the calcium aluminate, the content of CaO to Al2O3 is 1.5-2.0 by molar ratio, a vitrification rate is 80% or more, the content of anhydrous gypsum is 35-65 pts.mass with respect to 100 pts.mass of the total content of calcium aluminate and anhydrous gypsum, the contents of inorganic carbonate, hydroxycarboxylic acid and alum are 0.1 pt.mass or more, and the total content of inorganic carbonate, hydroxycarboxylic acid and alum is 10 pts.mass or less.SELECTED DRAWING: None

Description

The present invention relates to a fast-hardening mortar composition, particularly a fast-hardening mortar composition useful as a cross-section repair material and a pavement injection material.

The cross-section repair method is widely known as a method for repairing concrete structures that have deteriorated due to various causes. The cross-section repair method is a method in which a deteriorated part of concrete is removed by a chipping or the like, and the removed cross-section part is repaired with a cross-section repair material. As the cross-section restoration material used in this method, a mortar composition containing cement and fine aggregate is used. A cross-section repair material for the plastering method, a cross-section repair material for the spraying method, a cross-section repair material for the filling method, and a cross-section repair material for the prepacked method are used according to the mode of the cross-section repair method. On the other hand, as a cross-section repair material used in urgent repair work, there is also a quick-hardening mortar composition containing a quick-hardening admixture for early curing of the mortar composition in order to shorten the construction period. in use.

In addition, PC pavement and RC pavement are known as methods for constructing pavement such as roads, port facilities, and airport runways. PC pavement is a pavement in which a PC (prestressed concrete) pavement is placed on the roadbed and a backfill grout material is injected into the gap between the PC pavement and the roadbed. RC pavement is pavement in which RC (reinforced concrete) pavement is used instead of PC pavement. Furthermore, semi-flexible pavement is known as pavement for heavy traffic roads. Semi-flexible pavement is a pavement in which cement milk is injected into an open-grained asphalt mixture having a large porosity. A mortar composition containing cement and fine aggregate is also used as a pavement injection material used as a raw material for backfill grout materials used in PC pavement and RC pavement and cement milk used in semi-flexible pavement. May be done. The mortar composition used as this pavement injection material is usually fast-hardening and contains a fast-hardening admixture for early hardening of the cement in order to open the traffic the next morning after construction is done at night. It is a mortar composition.

As a fast-curing admixture for a fast-curing mortar composition, an admixture in which calcium aluminate and an inorganic sulfate are combined is known. However, the fast-curing admixture in which this calcium aluminate and the inorganic sulfate are combined has a strong effect of accelerating the curing of the mortar composition, and the mortar composition containing this fast-hardening admixture is mortar after adding water. There is a problem that the time until the composition starts to condense (condensation start time) is short and a sufficient pot life cannot be secured. Therefore, in the fast-curing admixture in which calcium aluminate and inorganic sulfate are combined, a coagulation adjusting agent is added in order to adjust the coagulation start time of the mortar composition. Inorganic carbonate, oxycarboxylic acid, and sodium aluminate are used as the coagulation regulator.

Patent Document 1 contains, as a main component, a hard-hardened cement containing 15 to 35% by weight of a hard-hardening component having a weight ratio of calcium aluminate to inorganic sulfate of 1: 0.5 to 3, and is divided by weight. Discloses an ultrafast hard cement composition containing 0.2 to 3% sodium aluminate, 0.2 to 5% inorganic carbonate, and 0.1 to 2% oxycarboxylic acids.

Patent Document 2 discloses a concrete cross-section restoration material containing a fast-curing admixture, a cement mineral, an aggregate, a re-emulsified powder resin, and a fiber. In Patent Document 2, sodium aluminate, inorganic carbonates and carboxylic acids are used as the coagulation adjuster of the quick-hardening admixture, and the particle size composition of these coagulation adjusters is the first having an average particle size of more than 45 μm and 90 μm or less. It contains 10 to 45% by mass of particles, 30 to 70% by mass of second particles having an average particle size of more than 90 μm and 150 μm or less, and 5 to 30% by mass of third particles having an average particle size of more than 150 μm and not more than 500 μm. Moreover, it is disclosed that the second particle is contained in a larger amount than the first particle and is contained in a larger amount than the third particle.

Patent Document 3 discloses a pavement injection material containing a fast-curing admixture, a cement mineral, sand, and a re-emulsified powder resin. In Patent Document 3, sodium aluminate, inorganic carbonates and carboxylic acids are used as the coagulation adjuster of the quick-hardening admixture, and the particle size composition of these coagulation adjusters is the first having an average particle size of more than 45 μm and 90 μm or less. It contains 10 to 45% by mass of particles, 30 to 70% by mass of second particles having an average particle size of more than 90 μm and 150 μm or less, and 5 to 30% by mass of third particles having an average particle size of more than 150 μm and not more than 500 μm. Moreover, it is disclosed that the second particle is contained in a larger amount than the first particle and is contained in a larger amount than the third particle.

Patent Document 4 describes a technique for suppressing fluctuations in the setting time of an ultrafast-hardening mortar composition mixed with a quick-hardening admixture when stored for a period of about 3 months, and maintaining good initial strength development for a long period of time. As a result, a clinker composed of calcium aluminate and a coagulation modifier (one or more of inorganic carbonate, oxycarboxylic acid, sodium aluminate and sodium sulfate) are mixed and pulverized to obtain an average particle size of calcium aluminate. It is disclosed that the particle size is within the range of 8 μm or more and 100 μm or less, and the average particle size of the coagulation modifier is 5 μm or less.

Special Fair 3-41420 Gazette Japanese Unexamined Patent Publication No. 2008-273762 Japanese Unexamined Patent Publication No. 2008-274580 Japanese Patent No. 6183571

Sodium aluminate, which is one of the coagulation modifiers added to the quick-hardening admixture, has the effect of increasing the initial strength (alkali stimulant) when added to the fast-hardening admixture containing calcium aluminate and anhydrous gypsum. (Effect of action) and the action of suppressing the occurrence of gypsum deposited on the surface of the cured product (optimization of the calcium component and the aluminum component in the initial hydration reaction). However, sodium aluminate exhibits remarkable deliquescent property, absorbs moisture during storage and dissolves, and loses its action, so that the above action may not be exhibited.

The present invention has been made in view of the above-mentioned circumstances, and is a fast-curing mortar composition capable of obtaining a cured product which is stable for a long period of time, has high initial strength, and suppresses the occurrence of vitiligo. The purpose is to provide.

In order to achieve the above object, the inventor of the present invention has conducted diligent studies, and as a result, the content of CaO with respect to _{Al 2} O _{3 is molar as calcium aluminate contained in the fast-curing admixture in the mortar composition.} The initial strength of the mortar composition is increased by using a mortar composition having a ratio in the range of 1.5 or more and 2.0 or less and having a vitrification rate of 80% or more and adding myoban instead of sodium aluminate. The present invention has been completed by finding that the action and the action of preventing the occurrence of white spots can be maintained at a high level even after long-term storage.

Therefore, the fast-curing mortar composition of the present invention is a fast-curing mortar composition containing a fast-curing admixture, cement and fine aggregate, and 100 parts by mass of the cement is added to 100 parts by mass of the fast-curing admixture. The fast-curing admixture contains calcium aluminate, anhydrous gypsum, inorganic carbonate, oxycarboxylic acid, and myoban, and the calcium aluminate is contained in an amount in the range of 2000 parts by mass or less. _{The content of CaO with respect to Al 2} O ₃ is in the range of 1.5 or more and 2.0 or less in terms of molar ratio, the vitrification rate is 80% or more, and the content of the anhydrous gypsum is the calcium. The content of the inorganic carbonate, the oxycarboxylic acid, and the myoban is within the range of 35 parts by mass or more and 65 parts by mass or less with respect to 100 parts by mass of the total amount of aluminate and the anhydrous gypsum, and the contents of the calcium are respectively. The total content of the inorganic carbonate, the oxycarboxylic acid and the myoban is 0.1 part by mass or more with respect to 100 parts by mass of the total amount of the aluminate and the anhydrous gypsum, and the total content of the calcium aluminate and the anhydrous is the calcium aluminate and the anhydrous. The total amount of gypsum is 10 parts by mass or less with respect to 100 parts by mass.

According to the quick-hardening mortar composition of the present invention, _{the content of CaO with respect to Al 2} O ₃ as the calcium aluminate contained in the quick-hardening admixture is within the range of 1.5 or more and 2.0 or less in terms of molar ratio. Therefore, since a vitrification rate of 80% or more is used, the initial strength can be improved and the occurrence of white spots can be suppressed. Further, according to the quick-hardening mortar composition of the present invention, since alum is used instead of sodium aluminate as the quick-hardening admixture, the effect of improving the initial strength and the effect of suppressing the occurrence of vitiligo are reduced over a long period of time. Hateful.

Here, in the quick-hardening mortar composition of the present invention, the fine aggregate may be contained in an amount in the range of 200 parts by mass or more and 1000 parts by mass or less with respect to 100 parts by mass of the quick-hardening admixture. ..
In this case, since the fine aggregate is contained in an amount within the above range, the initial strength development is excellent, and the cured product shrinks (self-shrinks) due to the curing of the fast-curing mortar composition and cures. Shrinkage (dry shrinkage) due to subsequent dissipation of water is suppressed. Therefore, the occurrence of cracks in the cured product can be suppressed, and the strength of the cured product is increased. Therefore, this quick-curing mortar composition is particularly useful as a cross-section restoration material.

Further, in the quick-hardening mortar composition of the present invention, the fine aggregate may be contained in an amount in the range of 10% by mass or more and 67% by mass or less with respect to the total amount of the quick-hardening mortar composition. ..
In this case, since the fine aggregate is contained in an amount within the above range, the initial strength development is excellent, and the fluidity of the special fine aggregate to which water is added is improved. Therefore, even in a fine space such as a void of an open-grained asphalt mixture in a semi-flexible pavement, the fine aggregate serves as a medium, so that it can be filled well. Therefore, this fast-curing mortar composition is particularly useful as a pavement injection material.

Further, in the fast-curing mortar composition of the present invention, sodium silicate is in the range of 0.1 part by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the total amount of the calcium aluminate and the anhydrous gypsum. It may be included in the amount of.
In this case, since the fast-curing mortar composition contains sodium silicate within the above range, the initial strength is further improved.

Further, in the quick-curing mortar composition of the present invention, anhydrous sodium sulfate is added in a range of 0.1 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the total amount of the calcium aluminate and the anhydrous gypsum. It may be included in the amount of.
In this case, since the fast-curing mortar composition contains anhydrous sodium sulfate within the above range, the fluidity is improved as well as the effect of improving the initial strength and the effect of suppressing the occurrence of vitiligo.

Further, in the fast-curing mortar composition of the present invention, the alum is potassium alum, and the content of the potassium alum is 0.2 mass with respect to 100 parts by mass of the total amount of the calcium alumate and the anhydrous gypsum. It may be in the range of 6 parts or more and 6.0 parts by mass or less.
In this case, since the fast-curing mortar composition contains potassium alum within the above range, the effect of improving the initial strength and the effect of suppressing the occurrence of vitiligo are more reliably improved.

Further, in the fast-curing mortar composition of the present invention, the alum may be contained as a mixture containing the inorganic powder and the alum in a mass ratio in the range of 20:80 to 80:20.
In this case, since alum is contained as a mixture with the inorganic powder, the alum in the quick-hardening mortar composition is easily dispersed uniformly, and the action of the alum is easily obtained.

Further, in the quick-hardening mortar composition of the present invention, short fibers composed of one or more of organic short fibers and carbon short fibers are further added in an amount of 0.05% by mass based on the total amount of the quick-hardening mortar composition. It may be contained in an amount within the range of 0.3% by mass or more.
In this case, since the short fibers act as a reinforcing material, the cured product obtained by curing the fast-curing mortar composition has improved crack resistance and excellent durability against fatigue.

Further, in the quick-hardening mortar composition of the present invention, the re-emulsified powder resin may be contained in an amount in the range of 0.5% by mass or more and 30% by mass or less with respect to the total amount of the quick-hardening mortar composition. good.
In this case, since the quick-hardening mortar composition contains the re-emulsified powder resin, the adhesive force to the concrete structure is improved.

Further, in the quick-hardening mortar composition of the present invention, silica fume may be further contained in an amount in the range of 1% by mass or more and 15% by mass or less with respect to the total amount of the quick-hardening mortar composition.
In this case, silica fume has a pozzolantic action, so that long-term strength development is improved. Further, the cured product obtained by curing the fast-curing mortar composition is densified, the total pore amount is reduced, and the progress of neutralization and the diffusion of chloride ions are suppressed, so that the durability is improved.

Further, in the quick-hardening mortar composition of the present invention, the synthetic polymer-based thickening water-retaining agent is further added in the range of 0.05% by mass or more and 5.00% by mass or less with respect to the total amount of the quick-hardening mortar composition. May be included in.
In this case, since the synthetic polymer-based thickening water-retaining agent has the effect of generating fine bubbles when in contact with water, the cured product obtained by curing the fast-curing mortar composition containing the synthetic polymer-based thickening water-retaining agent is pseudo. Entrained air is introduced into India, and in addition to the effect of adding the re-emulsified powder resin, freeze-thaw resistance is further improved.

According to the present invention, it is possible to provide a fast-curing mortar composition capable of obtaining a cured product which is stable for a long period of time, has high initial strength, and suppresses the occurrence of vitiligo.

Hereinafter, embodiments of the present invention will be described.
The quick-hardening mortar composition of the present embodiment contains a quick-hardening admixture, cement and fine aggregate. The quick-hardening mortar composition contains cement in a range of 100 parts by mass or more and 2000 parts by mass or less with respect to 100 parts by mass of the quick-hardening admixture. The fast-curing mortar composition may further contain admixtures such as short fibers, re-emulsified powder resin, silica fume, synthetic polymer-based thickening water retention agent, coagulation adjuster, antifreeze agent, and water reducing agent.
Hereinafter, each component of the fast-curing mortar composition of the present embodiment will be described.

(Fast-hardening admixture)
The fast-curing admixture contains calcium aluminate, gypsum anhydride, inorganic carbonate, oxycarboxylic acid, and alum. Calcium aluminate and anhydrous gypsum act as a fast-hardening component that accelerates the curing rate of the mortar composition. Inorganic carbonate, oxycarboxylic acid, and alum act as a setting adjusting component for adjusting the setting time, initial strength, and the like of the mortar composition.

Calcium aluminate is generally a compound having a composition such as _{12CaO · 7Al 2 O 3, 11CaO} · 7Al 2 O 3 · CaF 2 and CaO · _Al 2 _{O 3. The content of CaO with respect to Al 2} O ₃ of calcium aluminate is in the range of 1.5 or more and 2.0 or less in terms of molar ratio. If the _{CaO content with respect to Al 2} O ₃ is out of the above range, it may be difficult to obtain the action of improving the initial strength of the mortar composition and the action of preventing the occurrence of vitiligo.

Further, calcium aluminate has a vitrification rate of 80% or more. If the vitrification rate is too low, it may be difficult to obtain the effect of improving the initial strength of the mortar composition. The vitrification rate is preferably in the range of 80% or more and 99% or less, and particularly preferably in the range of 90% or more and 99% or less.
The vitrification rate (%) of the calcium aluminate is determined by fitting the crystalline portion (peak) and the amorphous portion halo from the X-ray diffraction pattern measured by the X-ray diffraction method of the calcium aluminate of the sample. , It is a value obtained by applying each integrated strength to the following formula to calculate the vitrification rate.
Vitrification rate (%) = 100- (100 x Ic / (Ic + Is))
Ic: Crystalline scattering integral strength Is: Amorphous scattering integral strength

Calcium aluminate is preferably Blaine specific surface area is in 3000 cm ² / g or more 5500cm ² / g within the range. When the brain specific surface area of the calcium aluminate is within the above range, the curing rate of the fast-curing mortar composition can be increased, and the action of improving the initial strength is improved.

The anhydrous gypsum preferably has a brain specific surface area in ^{the range of 8000 cm 2} / g or more and 12000 cm ² / g or less. When the brain specific surface area of the anhydrous gypsum is within the above range, the curing rate of the fast-curing mortar composition can be increased, and the action of improving the initial strength is improved.

The content of anhydrous gypsum is in the range of 35 parts by mass or more and 65 parts by mass or less with respect to 100 parts by mass of the total amount of calcium aluminate and anhydrous gypsum. By containing calcium aluminate and anhydrous gypsum in the above proportions, the curing rate of the fast-curing mortar composition can be increased, and the action of improving the initial strength is improved.

The inorganic carbonate is preferably an alkali metal carbonate or a hydrogen carbonate. Examples of inorganic carbonates include sodium carbonate, potassium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, lithium carbonate and ammonium carbonate. One of these inorganic carbonates may be used alone, or two or more of them may be used in combination.

Examples of oxycarboxylic acids include tartaric acid, citric acid, malic acid, gluconic acid and maleic acid. One of these oxycarboxylic acids may be used alone, or two or more of these oxycarboxylic acids may be used in combination. A salt may be used as the oxycarboxylic acid. The salt is preferably a metal salt such as a sodium salt, a calcium salt, or an aluminum salt.

Alum contains aluminum and acts as an aluminum aid, similar to sodium aluminate used in conventional fast-curing admixtures. Therefore, it is preferable that the quick-hardening admixture substantially does not contain sodium aluminate.

The alum, sodium alum _{(NaAl (SO 4) 2 ·} 12H 2 O), it is preferable to use potassium alum _{(AlK (SO 4) 2 ·} 12H 2 O), in particular, it is preferable to use a potassium alum. The average particle size of alum is preferably in the range of 1 μm or more and 100 μm or less.

The contents of the inorganic carbonate, oxycarboxylic acid and alum are 0.1 parts by mass or more with respect to 100 parts by mass of the total amount of the quick-hardening components (calcium aluminate and anhydrous gypsum), and their total contents are However, it is preferable that the total amount of the quick-hardening components is within the range of 10 parts by mass or less with respect to 100 parts by mass. If the contents of the inorganic carbonate, oxycarboxylic acid and alum are too low, the effect of adding these components may be difficult to obtain. On the other hand, if the contents of the inorganic carbonate, oxycarboxylic acid and alum are too large, the content of the quick-hardening component is relatively low, and the effect of the quick-hardening component may be difficult to obtain. In order to surely obtain the effect of adding the inorganic carbonate, oxycarboxylic acid and myoban, the contents of the inorganic carbonate, oxycarboxylic acid and myoban are 100, which is the total amount of the quick-hardening components (calcium aluminate and anhydrous gypsum), respectively. It is preferably in the range of 0.2 parts by mass or more and 6.0 parts by mass or less with respect to parts by mass.

The fast-curing admixture may further contain anhydrous sodium sulfate (anhydrous neutral Glauber's salt), sodium silicate, and bulking material.

Anhydrous sodium sulfate has a high dissolution rate in water and has an effect of improving the fluidity of the fast-curing mortar composition after adding water. The blending amount of anhydrous sodium sulfate is preferably in the range of 0.1 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the total amount of calcium aluminate and anhydrous gypsum.

Sodium silicate acts as an alkalinity regulator and has the effect of increasing the initial strength of the fast-curing mortar composition. Examples of sodium silicate include sodium metasilicate (Na ₂ SiO ₃ ), sodium orthosilicate (Na ₄ SiO ₄ ), sodium disilicate (Na ₂ Si ₂ O ₅ ), and sodium tetrasilicate (Na ₂ Si _4). O ₉ ) can be used. Moreover, sodium silicate may be anhydrous, hydrates _{(e.g., Na 2 SiO 3 · 9H 2} O) may be. The blending amount of sodium silicate is preferably in the range of 0.1 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the total amount of calcium aluminate and anhydrous gypsum.

As the bulking material, an inorganic powder that does not contribute to the curing reaction of the fast-curing mortar composition can be used in the absence of water. Examples of the inorganic powder include quartz fine powder, limestone fine powder, coal ash fine powder, blast furnace slag fine powder and the like.
It is preferable that the fast-curing admixture is contained as a mixture in which a coagulation adjusting component such as an inorganic carbonate, an oxycarboxylic acid and alum is mixed in advance with the bulking material. By using a mixture of the coagulation adjusting components, it is possible to prevent consolidation due to consolidation during storage (prevention of blocking), so that the coagulation adjusting components in the fast-curing admixture are easily dispersed uniformly, and the action of the coagulation adjusting components. Is easy to obtain. The mixture preferably contains the inorganic powder and the coagulation adjusting component in a mass ratio of 20:80 to 80:20.

The fast-curing admixture can be produced, for example, by mixing calcium aluminate, gypsum anhydride, inorganic carbonate, oxycarboxylic acid, and alum. As the mixing device, various mixing devices usually used as a mixing device for cement materials such as a V-type mixer, a ribbon mixer, and a pro-share mixer can be used.

The order of mixing is not particularly limited, but first, calcium aluminate and anhydrous gypsum are mixed, and the obtained mixture is mixed with inorganic carbonate, oxycarboxylic acid, myoban, and if necessary, anhydrous sodium sulfate. It is preferable to add sodium silicate or sodium silicate and mix. Inorganic carbonate, oxycarboxylic acid, and alum may be added as a mixture with the above-mentioned inorganic powder, or may be mixed with calcium aluminate or anhydrous gypsum.

(cement)
As the cement, ordinary Portland cement, early-strength Portland cement, moderate heat Portland cement, low heat Portland cement, blast furnace cement, silica cement, fly ash cement, silica fume cement and the like can be used. One type of cement may be used alone, or two or more types may be used in combination. As the cement, it is preferable to use Portland cement, particularly ordinary Portland cement.

The blending amount of cement is generally in the range of 100 parts by mass or more and 2000 parts by mass or less of cement with respect to 100 parts by mass of the fast-curing admixture. When the blending amount of cement is within the above range, a fast-hardening mortar composition having excellent initial strength development by the quick-hardening admixture and long-term strength development by cement can be obtained.

(Fine aggregate)
The fine aggregate has an effect of suppressing the shrinkage (self-shrinkage) of the cured product due to the curing of the fast-curing mortar composition and the shrinkage (dry shrinkage) due to the dissipation of water after curing. The fine aggregate is preferably sand, more preferably sand having a particle size of 150 to 3000 μm, and even more preferably sand having a particle size of 200 to 1500 μm. Further, the sand may have a particle size of 90 to 1000 μm, and may be sand having a particle size of 90 to 200 μm. If the particle size of the sand becomes too small, the stirring performance of the mortar or cement milk prepared by mixing the quick-hardening mortar composition and water and the abrasion resistance of the cured product may decrease, and the slip resistance may decrease. be. On the other hand, if the particle size of the sand becomes too large, the sand tends to settle in the mortar or cement milk, and the adhesion of the mortar or cement milk to the concrete structure and the injectability into the pavement may decrease. be.

The blending amount of the fine aggregate is, for example, in the range of 200 parts by mass or more and 1000 parts by mass or less as the amount with respect to 100 parts by mass of the quick-hardening admixture when used as a cross-section repair material. If the blending amount of the fine aggregate is too small, not only the shrinkage reducing effect of the cured product cannot be sufficiently obtained, but also the stirring performance and wear resistance of the mortar may be lowered and the slip resistance may be lowered. On the other hand, if the blending amount of the fine aggregate is too large, the initial strength development may be lowered and the material separation may occur, so that bleeding may easily occur. On the other hand, when used as an injection material for pavement, the amount is in the range of 10% by mass or more and 67% by mass or less with respect to the total amount of the quick-hardening mortar composition. If the amount of the fine aggregate is too small, not only the shrinkage reducing effect of the cured product cannot be sufficiently obtained, but also the stirring performance and abrasion resistance of the cement milk may be lowered and the slip resistance may be lowered. .. On the other hand, if the blending amount of the fine aggregate is too large, the expression of the initial strength may decrease and the material may be separated and bleeding may easily occur.

(Short fiber)
The short fibers act as a reinforcing material. Therefore, the cured product obtained by curing the fast-curing mortar composition containing short fibers has improved crack resistance and excellent durability against fatigue.
As the short fibers, organic short fibers and carbon short fibers can be used. Examples of organic short fibers include PVA short fibers (polyvinyl alcohol short fibers), nylon short fibers, aramid short fibers, polypropylene short fibers, rayon short fibers and the like. These short fibers may be used alone or in combination of two or more.
The short fibers preferably have a fiber length in the range of 1 mm or more and 10 mm or less. If it is shorter than 1 mm, a sufficient fiber reinforcing effect may not be obtained. On the other hand, if it exceeds 10 mm, the fluidity is impaired due to the resistance of the fibers, and the workability may be impaired, for example, the injectability into a narrow portion or a semi-flexible pavement is lowered. The fiber diameter is usually in the range of 5 μm or more and 100 μm or less.

The blending amount of the short fibers is generally in the range of 0.05% by mass or more and 0.3% by mass or less as the amount with respect to the total amount of the fast-curing mortar composition. If the amount of the short fibers blended is too small, the crack resistance of the cured product may be improved, and the action of improving the durability against fatigue may be insufficient. On the other hand, if the blending amount of the short fibers is too large, the fluidity of the mixture of the fast-curing mortar composition and water may decrease.

(Re-emulsified powder resin)
The re-emulsified powder resin is a resin having low water absorption and water permeability, and has an effect of making it difficult for water to permeate into a cured product obtained by curing a quick-curing mortar composition. Further, the re-emulsified powder resin has an effect of improving the adhesive force of the quick-hardening mortar composition to the concrete structure. Therefore, the quick-hardening mortar composition containing the re-emulsified powder resin has excellent freeze-thaw resistance after being immersed in water, and the adhesive force to the concrete structure is improved.
Examples of the re-emulsified powder resin include vinyl acetate / beova / acrylic ester copolymer resin, vinyl acetate copolymer resin, vinyl acetate / ethylene copolymer, vinyl acetate / acrylic copolymer resin, acrylic resin and the like. These re-emulsified powder resins may be used alone or in combination of two or more.

The blending amount of the re-emulsified powder resin is generally in the range of 0.5% by mass or more and 30% by mass or less as the amount with respect to the total amount of the quick-hardening mortar composition. If the blending amount of the re-emulsified powder resin is too small, the action of improving the freeze-thaw resistance of the cured product of the fast-curing mortar composition may be insufficient. On the other hand, if the amount of the re-emulsified powder resin is too large, the fluidity of the mixture of the fast-curing mortar composition and water may decrease.

(Silica fume)
Silica fume has a pozzolantic effect. Therefore, the fast-curing mortar composition containing silica fume has improved long-term strength development, and the cured product obtained by curing the silica fume is densified to reduce the total pore amount, so that the neutralization progresses and chloride ions are produced. The progress of diffusion of mortar is suppressed.

The blending amount of silica fume is preferably in the range of 1% by mass or more and 15% by mass or less as the amount with respect to the total amount of the quick-curing mortar composition. If the amount of silica fume blended is too small, the long-term strength development due to the pozzolan reaction, the neutralization inhibitory effect due to the densification of the cured product structure of the fast-curing mortar composition, and the effect of suppressing the permeation of chloride ions are sufficient. May disappear. On the other hand, if the blending amount of silica fume is too large, the amount of the quick-hardening admixture in the quick-hardening mortar composition becomes relatively small, and the initial strength development may be deteriorated.

(Synthetic polymer-based thickening water retention agent)
Synthetic polymer-based thickening water retention agents have the effect of generating fine bubbles when in contact with water. Therefore, the cured product obtained by curing the fast-curing mortar composition containing the synthetic polymer-based thickening water-retaining agent has pseudo-entrained air introduced into it, and has freeze-thaw resistance similar to the effect of adding the re-emulsified powder resin. Is improved.

The blending amount of the synthetic polymer-based thickening water retention agent is preferably in the range of 0.05% by mass or more and 5.0% by mass or less as the amount with respect to the total amount of the quick-curing mortar composition, and is 0.10% by mass. It is more preferably in the range of 5.0% by mass or less, and particularly preferably in the range of 1.00% by mass or more and 5.0% by mass or less. If the amount of the synthetic polymer-based thickening water-retaining agent is too small, the action of improving the freeze-thaw resistance of the cured product of the fast-curing mortar composition may be insufficient. On the other hand, if the amount of the synthetic polymer-based thickening water-retaining agent is too large, not only the fluidity of the mixture of the quick-hardening mortar composition and water is lowered, but also excessive air bubbles may enter and the strength may be lowered.

(Condensation adjuster)
In the quick-hardening mortar composition of the present embodiment, as described above, the coagulation modifier is contained as fine particles having an average particle diameter of 5 μm or less as a constituent component of the quick-hardening admixture. Further, the coagulation adjuster may be added so that the content of the coagulation adjuster is in the range of 0.01% by mass or more and 5% by mass or less. Here, the content of the coagulation adjuster with respect to the total amount of the quick-hardening mortar composition is the same as that of the coagulation adjuster contained in the quick-hardening admixture and the coagulation adjuster added separately from the quick-hardening admixture. The total amount. In this case, since the coagulation time can be adjusted by the coagulation adjuster contained in the quick-hardening admixture and the coagulation adjuster added separately from the fast-hardening admixture, the speed due to the environmental temperature and long-term storage can be adjusted. Fluctuations in the settling onset time of the rigid mortar composition can be further reliably reduced. Further, by adding a coagulation adjusting agent separately, the setting starting time of the fast-curing mortar composition can be adjusted to a required time. Further, in the quick-hardening mortar composition of the present embodiment, the coagulation adjuster contained in the quick-hardening admixture is fine particles and easily dissolved in water, and usually a sufficient pot life can be secured, so that it is added separately. The amount of coagulation modifier can be reduced.
If the content of the coagulation adjuster with respect to the total amount of the fast-curing mortar composition is less than 0.01% by mass, the action of adjusting the coagulation time may be insufficient. On the other hand, if the content of the coagulation adjuster exceeds 5% by mass with respect to the total amount of the quick-curing mortar composition, the expression of long-term strength by the mortar may decrease.

The coagulation adjuster to be added separately from the quick-hardening admixture may be added to the quick-hardening mortar composition alone, but it is preferable to add it as a mixture in which the inorganic powder and the coagulation adjuster are mixed in advance. The mixture of the inorganic powder and the coagulation adjuster is preferably a mixture containing a high concentration of the coagulation adjuster containing 50 parts by mass or more and 300 parts by mass or less of the coagulation adjuster with respect to 100 parts by mass of the inorganic powder. By adding the coagulation adjuster to the fast-curing mortar composition as a mixture containing a high concentration of the coagulation adjusting agent, the coagulation adjusting agent can be easily dispersed uniformly in the fast-curing mortar composition. As the inorganic powder, cement (particularly Portland cement), limestone powder, silica stone powder, blast furnace slag powder, coal ash, fly ash, clay mineral, calcium aluminate powder, and inorganic sulfate powder can be used. The inorganic powder is preferably a fine powder having a brain specific surface area in ^{the range of 2500 cm 2} / g or more and 5000 cm ^{2 / g or less.} Since the inorganic powder having a brain specific surface area within the above range has high dispersibility, the mixture containing a high concentration of the coagulation modifier using this inorganic powder can be easily uniformly dispersed in the quick-hardening mortar composition. The particle size of the coagulation adjuster contained in the mixture containing a high concentration of the coagulation adjuster is preferably in the range of 1 μm or more and 500 μm or less. The coagulation adjuster having a particle size within the above range has high dispersibility in the inorganic powder, and it becomes easy to prepare a mixture containing a high concentration of the coagulation adjuster having a uniform composition.

(Antifreeze)
Sodium acetate, calcium acetate, and calcium nitrite react with water to generate heat, and as an antifreeze agent to prevent freezing of a mixture of quick-hardening mortar composition and water in an extremely low temperature environment where water freezes. It works. Therefore, the quick-hardening mortar composition containing an antifreeze agent can suppress freezing of the quick-hardening mortar composition kneaded with water even in an extremely low temperature environment, and the initial strength development is enhanced.
As the antifreeze agent, one type may be used alone, or two or more types may be used in combination.

The blending amount of the antifreeze agent is generally in the range of 1% by mass or more and 10% by mass or less as the amount with respect to the total amount of the quick-hardening mortar composition. If the amount of the antifreeze compound is too small, the action as the antifreeze agent becomes insufficient, and the quick-hardening mortar composition may freeze and lose its strength at all. On the other hand, if the amount of the antifreeze agent is too large, a salting-out action may occur in the mixture of the quick-hardening mortar composition and water, and the fluidity may decrease.

(Water reducing agent)
The fast-curing mortar composition used as a grout material may contain a water reducing agent. The water reducing agent has the effect of improving the fluidity of the grout material and facilitating the injection of the grout material into the gap under the concrete pavement slab by natural flow. As the water reducing agent, a commercially available polycarboxylic acid salt-based high-performance water reducing agent (trade name: Melflux, etc.) can be used.

The blending amount of the water reducing agent is generally in the range of 0.05% by mass or more and 1.0% by mass or less as the amount with respect to the total amount of the quick-hardening mortar composition. If the amount of the water reducing agent is too small, the action as a water reducing agent may be insufficient. On the other hand, if the blending amount of the water reducing agent is too large, the fluidity of the grout material becomes excessive, causing material separation, and the fibers may float on the upper surface of the grout material.

According to the fast-curing mortar composition of the present embodiment having the above-mentioned structure, _{the content of CaO with respect to Al 2} O ₃ as the calcium aluminate contained in the fast-hardening admixture is 1.5 or more in terms of molar ratio. Since those having a vitrification rate of 80% or more within the range of 2.0 or less are used, the initial strength can be improved and the occurrence of white spots can be suppressed. Further, according to the quick-hardening mortar composition of the present embodiment, since alum is used instead of sodium aluminate as the quick-hardening admixture, the effect of improving the initial strength and the effect of suppressing the occurrence of vitiligo are reduced over a long period of time. It's hard to do.

Further, in the quick-hardening mortar composition of the present embodiment, when the fine aggregate is contained in an amount in the range of 200 parts by mass or more and 1000 parts by mass or less with respect to 100 parts by mass of the quick-hardening admixture, the initial strength is exhibited. In addition to being excellent in properties, shrinkage of the cured product due to curing of the fast-curing mortar composition (self-shrinkage) and shrinkage due to the dissipation of water after curing (dry shrinkage) are suppressed. Therefore, the occurrence of cracks in the cured product can be suppressed, and the strength of the cured product is increased. Therefore, this quick-curing mortar composition is particularly useful as a cross-section restoration material.

Further, in the quick-hardening mortar composition of the present embodiment, when the fine aggregate is contained in the range of 10% by mass or more and 67% by mass or less with respect to the total amount of the quick-hardening mortar composition, the initial strength is exhibited. It has excellent properties and improves the fluidity of the special fine aggregate to which water is added. Therefore, even in a fine space such as a void of an open-grained asphalt mixture in a semi-flexible pavement, the fine aggregate serves as a medium, so that it can be filled well. Therefore, this fast-curing mortar composition is particularly useful as a pavement injection material.

Further, in the fast-curing mortar composition of the present embodiment, sodium silicate is further contained in the range of 0.1 part by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the total amount of calcium aluminate and anhydrous gypsum. By including in the amount of, the initial strength is further improved.

Further, in the fast-curing mortar composition of the present embodiment, anhydrous sodium sulfate is further added in the range of 0.1 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the total amount of calcium aluminate and anhydrous gypsum. By including the amount of, the fluidity is improved as well as the effect of improving the initial strength and the effect of suppressing the occurrence of gypsum.

Further, in the fast-curing mortar composition of the present embodiment, the alum is potassium alum, and the content of potassium alum is 0.2 parts by mass or more with respect to 100 parts by mass of the total amount of calcium aluminate and anhydrous gypsum 6 When it is within the range of 0.0 parts by mass or less, the effect of improving the initial strength and the effect of suppressing the occurrence of alum are more reliably improved.

Further, in the fast-curing mortar composition of the present embodiment, alum is contained as a mixture containing the inorganic powder and alum in an amount in the range of 20:80 to 80:20 in terms of mass ratio. The alum in the rigid mortar composition is easily dispersed uniformly, and the action of the alum is easily obtained.

The effects of the present invention will be described in more detail in Examples.
The types, compositions and abbreviations of the materials used in this example are shown in Table 1 below.

[Preparation of crushed calcium aluminate]
The calcium aluminate clinker shown in Table 2 below was prepared. To 100 parts by mass of calcium aluminate clinker, 1.0 part by mass of sodium carbonate (N) and 0.5 part by mass of tartrate (Ta) were added, and a blending pulverizer was used to obtain a brain specific surface area of 4500 cm ² / g. The mixture was pulverized to obtain a pulverized calcium aluminate product. The composition of the obtained pulverized calcium aluminate and the measured values of the specific surface area of the brain are shown in Table 3 below.

[Example 1 of the present invention]
A mixture of calcium aluminate and gypsum is prepared by putting the pulverized calcium aluminate into a V-type mixer at a ratio of 45 parts by mass as the amount of calcium aluminate and 55 parts by mass of anhydrous gypsum (CS) and mixing for 10 minutes. Obtained. To 100 parts by mass of the obtained mixture, 6.0 parts by mass of potassium alum mixture (BK) and 0.6 parts by mass of sodium metasilicate (MS) were added, and the mixture was further mixed for 10 minutes to achieve fast curing. An admixture (SA) was prepared. With respect to 100 parts by mass of the obtained fast-curing admixture (SA), 400 parts by mass of ordinary Portland cement (N), 500 parts by mass of fine aggregate (S), 8 parts by mass of coagulation adjuster (SET), and water reducing agent ( 6681F) 1.5 parts by mass and 1.2 parts by mass of antifoaming agent (14HP) were mixed to prepare a quick-hardening mortar composition.

[Comparative Example 1]
This book except that 1.0 part by mass of sodium aluminate (AL) was added instead of potassium alum mixture (BK) and sodium metasilicate (MS) to 100 parts by mass of the mixture of calcium aluminate and gypsum. A fast-curing admixture (SA) was produced in the same manner as in Invention Example 1. Then, a fast-hardening mortar composition was prepared in the same manner as in Example 1 of the present invention, except that the obtained fast-hardening admixture (SA) was used.

The composition of the fast-curing admixture (SA) produced in Example 1 of the present invention and Comparative Example 1 is shown in Table 4 below. The compositions of the fast-curing mortar compositions prepared in Example 1 of the present invention and Comparative Example 1 are shown in Table 5 below.

[evaluation]
A mortar was prepared by mixing 100 parts by mass of the fast-curing mortar composition obtained in Example 1 and Comparative Example 1 of the present invention with water at a ratio of 18 parts by mass. The quick-curing mortar composition used immediately after production (within 1 day after production). With respect to the obtained mortar, the physical characteristics of J14 funnel flow time, setting time, and compressive strength were measured by the following methods. In addition, it was confirmed whether or not there was vitiligo on the specimen whose age was 28 days, which was obtained by measuring the compressive strength. Each physical property was measured at each environmental temperature of 5 ° C, 20 ° C, and 35 ° C. The results are shown in Table 6 below.

(J14 funnel flow time)
The measurement was performed in accordance with the JSCE standard JSCE-F 541 “Fluidity test method for filled mortar”.

(Condensation time)
The measurement was performed in accordance with JIS R 5201 “Physical test method for cement”.

(Compression strength)
The measurement was performed in accordance with JIS R 5201 “Physical test method for cement”.

The fast-curing mortar compositions obtained in Example 1 and Comparative Example 1 of the present invention are packed in a plastic bag (capacity: 12 L), and pinholes (hole diameter: 0.5 mm) are opened at four corners of the plastic bag. , The temperature was 30 ° C., and the humidity was 80% RH. Using the fast-curing mortar composition after storage for 3 months and storage for 6 months, a mortar was prepared and evaluated in the same manner as described above. The physical properties were measured at an environmental temperature of 20 ° C. The results are shown in Table 7 below together with the results of the mortar prepared using the fast-curing mortar composition immediately after production.

From the results shown in Table 6, no clear difference was observed between Example 1 of the present invention and Comparative Example 1 for the mortar prepared using the quick-curing mortar composition immediately after production. In addition, from the results in Table 7, it was confirmed that Example 1 of the present invention exhibits the same physical characteristics immediately after production, after storage for 3 months, and after storage for 6 months. On the other hand, in Comparative Example 1, it was confirmed that as the protection period became longer, the J14 funnel flow time and the setting time became longer, the compression strength became lower, and vitiligo was more likely to occur. It is considered that this is because the sodium aluminate contained in the fast-curing mortar composition of Comparative Example 1 was moistened and dissolved during storage, and its action was lost.

[Examples 2 to 6 of the present invention]
The fast-hardening mortar composition produced in Example 1 of the present invention contains PVA short fibers (PVA) as organic short fibers in an amount of 0.05% by mass based on the total amount of the fast-hardening mortar composition (Example 2 of the present invention). , 0.1% by mass (Example 3 of the present invention), 0.5% by mass (Example 4 of the present invention), 1.0% by mass (Example 5 of the present invention), 3.0% by mass (Example 6 of the present invention). Each of them was added in an amount and mixed to prepare an organic short fiber-containing fast-curing mortar composition of Examples 2 to 6 of the present invention. An organic short fiber-containing mortar was prepared by mixing the obtained organic short fiber-containing quick-hardening mortar composition 100 with a ratio of 18 parts by mass of water.

The obtained organic short fiber-containing mortar was subjected to a fatigue test when flowing down the J14 funnel. The fatigue test was carried out by a method based on the former JSTM C 7104: 1999 “Concrete Fatigue Test Method by Repeated Compressive Stress”. The level of the fatigue test was static compressive strength: 50 N / mm ² , upper limit stress ratio: 65%, lower limit stress ratio: 10%, repetition rate: 10 Hz, and the dimensions of the specimen were φ50 × 100 mm. The results are shown in Table 8 below together with the measurement results of the mortar prepared using the fast-curing mortar composition immediately after the production of Example 1 of the present invention.

From the results in Table 8, the compression fatigue durability of the specimen (cured product) prepared using the fast-curing mortar composition containing PVA short fibers was greatly improved even when the amount of short fibers added was 0.05% by mass. However, it was confirmed that the amount of short fibers added was significantly improved to 0.1% by mass or more, and that the condition of the specimen was sound even if the number of repetitions was 2 million.

[Examples 7 to 12 of the present invention]
In the fast-curing mortar composition prepared in Example 1 of the present invention, the contents of the re-emulsified powder resin (P) with respect to the total amount of the fast-hardening mortar composition were 0.5% by mass% (Example 7 of the present invention) and 1.0, respectively. Mass% (Example 8 of the present invention), 2.0 mass% (Example 9 of the present invention), 5.0 mass% (Example 10 of the present invention), 10.0 mass% (Example 11 of the present invention), 15.0 mass% (Example 12 of the present invention) were added and mixed to prepare the re-emulsified powder resin-containing fast-curing mortar compositions of Examples 7 to 12. A re-emulsified powder resin-containing mortar was prepared by mixing 100 parts by mass of the obtained re-emulsified powder resin-containing quick-hardening mortar composition with water at a ratio of 18 parts by mass.

The J14 funnel flow time was measured for the obtained re-emulsified powder resin-containing mortar. Further, the obtained mortar was applied to the surface of a concrete flat plate that had been roughened with a water jet by a dry spraying method. The applied re-emulsified powder resin-containing mortar was sealed and cured until the age of 28 days and cured. The compressive strength of the obtained cured mortar and the adhesive strength between the cured product and the concrete flat plate were measured. The adhesion strength was measured using a Kenken-type adhesion tester. The results are shown in Table 9 below together with the measurement results of the mortar prepared using the fast-curing mortar composition immediately after the production of Example 1 of the present invention.

From the results in Table 9, it was confirmed that the cured product prepared by using the re-emulsified powder resin-containing quick-hardening mortar composition had improved adhesion strength with the concrete flat plate.

[Examples 13 to 16 of the present invention]
In the fast-curing mortar composition prepared in Example 1 of the present invention, the contents of silica fume (SF) with respect to the total amount of the fast-hardening mortar composition were 1.0% by mass (Example 13 of the present invention) and 5.0% by mass, respectively (Example 13 of the present invention). Inventive Example 14), 10.0% by mass (Invention Example 15), 15.0% by mass (Invention Example 16), respectively, added and mixed to contain silica fumes of Invention Examples 13 to 16. A fast-curing mortar composition was prepared. A silica fume-containing mortar was prepared by mixing the obtained silica fume-containing quick-hardening mortar composition with water at a ratio of 18 parts by mass with respect to 100 parts by mass. The obtained silica fume-containing mortar was poured into a mold having a size of 100 × 100 × 400 mm to prepare a test piece. The neutralization depth, chloride ion diffusion coefficient, and total pore amount of the prepared test piece were measured by the following methods. The results are shown in Table 10 below together with the measurement results of the mortar prepared using the fast-curing mortar composition immediately after the production of Example 1 of the present invention.

(Measurement method of neutralization depth)
The measurement was carried out by carrying out an accelerated test having _{a CO 2} concentration of 5% in accordance with JIS A 1153 “Promoted Neutralization Test Method for Concrete”.
(Measurement method of chloride ion diffusion coefficient)
The measurement was performed in accordance with the Japan Society of Civil Engineers standard JSCE-G 572 "Test method for apparent diffusion coefficient of chloride ions in concrete by immersion".
(Measuring method of total pore amount)
It was measured by a mercury press-fitting porosimeter.

From the results in Table 10, the total pore size of the test piece (cured body) prepared using the silica fume-containing quick-hardening mortar composition was reduced, which suppressed the progress of neutralization and the progress of chloride ion diffusion. It was confirmed that it would be done.

[Examples 17 to 22 of the present invention]
In the fast-curing mortar composition prepared in Example 1, the contents of the synthetic polymer-based thickening water-retaining agent (Ad) with respect to the total amount of the fast-hardening mortar composition were 0.05% by mass% (Example 17 of the present invention) and 0, respectively. .10% by mass (Example 18 of the present invention), 0.50% by mass (Example 19 of the present invention), 1.00% by mass (Example 20 of the present invention), 3.00% by mass (Example 21 of the present invention), 5.00 Each was added in an amount of mass% (Example 22 of the present invention) and mixed to prepare a fast-curing mortar composition containing a thickening water-retaining agent of Examples 17 to 22 of the present invention. A synthetic polymer-based thickening water-retaining agent-containing mortar was prepared by mixing 100 parts by mass of water with respect to 100 parts by mass of the obtained synthetic polymer-based thickening water-retaining agent-containing quick-hardening mortar composition.

For the obtained synthetic polymer-based thickening water-retaining agent-containing mortar, the J14 funnel flow time and the compressive strength at 2 days of age were measured. In addition, a freeze-thaw test was carried out using the obtained mortar containing a synthetic polymer-based thickening water-retaining agent. The test method was carried out up to 300 cycles in accordance with JIS A 1145 “Concrete freeze-thaw test method”, and the relative dynamic elastic modulus was measured with the dynamic elastic modulus at the 50th cycle as 100%. The results are shown in Table 11 below together with the measurement results of the mortar prepared using the fast-curing mortar composition immediately after the production of Example 1 of the present invention.

From the results in Table 11, it was confirmed that the J14 funnel flow time of the mortar increased as the amount of the synthetic polymer-based thickening water retention agent added increased, that is, the viscosity of the mortar increased. Further, the cured product of the mortar prepared by using the mortar in which the amount of the synthetic polymer-based thickening water retention agent added is 0.05% by mass or more has a relative dynamic elastic modulus of 50% or more after the end of 300 cycles, and a freeze-thaw test. Freezing and thawing resistance in In particular, when the amount of the synthetic polymer-based thickening water retention agent added was 0.10% or more, the kinematic elastic modulus after the end of 300 cycles was 70% or more, and the freeze-thaw resistance was further improved. Further, when the addition amount of the synthetic polymer-based thickening water retention agent was 1.00% or more, the kinematic elastic modulus after the end of 300 cycles was 100%, and it was confirmed that the freeze-thaw resistance was significantly improved.

Claims (13)

A fast-curing mortar composition containing a fast-curing admixture, cement and fine aggregate.
The cement is contained in an amount in the range of 100 parts by mass or more and 2000 parts by mass or less with respect to 100 parts by mass of the fast-curing admixture.
The fast-curing admixture contains calcium aluminate, gypsum anhydride, inorganic carbonate, oxycarboxylic acid, and alum.
The calcium aluminate has a CaO content of Al2O3 in a molar ratio of 1.5 or more and 2.0 or less, and a vitrification rate of 80% or more.
The content of the anhydrous gypsum is in the range of 35 parts by mass or more and 65 parts by mass or less with respect to 100 parts by mass of the total amount of the calcium aluminate and the anhydrous gypsum.
The contents of the inorganic carbonate, the oxycarboxylic acid, and the alum are 0.1 parts by mass or more with respect to 100 parts by mass of the total amount of the calcium aluminate and the anhydrous gypsum, respectively, and the inorganic carbonate, A fast-curing mortar composition characterized in that the total content of the oxycarboxylic acid and the alum is 10 parts by mass or less with respect to 100 parts by mass of the total amount of the calcium aluminate and the anhydrous gypsum. The quick-hardening mortar composition according to claim 1, wherein the fine aggregate is contained in an amount in the range of 200 parts by mass or more and 1000 parts by mass or less with respect to 100 parts by mass of the quick-hardening admixture. The quick-curing mortar composition according to claim 2, wherein the material is a cross-section restoration material. The quick-hardening mortar composition according to claim 1, wherein the fine aggregate is contained in an amount in the range of 10% by mass or more and 67% by mass or less with respect to the total amount of the quick-hardening mortar composition. The fast-curing mortar composition according to claim 4, which is an injection material for pavement. Further, any of claims 1 to 5, wherein sodium silicate is contained in an amount in the range of 0.1 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the total amount of the calcium aluminate and the anhydrous gypsum. The fast-curing mortar composition according to item 1. Further, any of claims 1 to 6, wherein anhydrous sodium sulfate is contained in an amount in the range of 0.1 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the total amount of the calcium aluminate and the anhydrous gypsum. The fast-curing mortar composition according to item 1. The alum is potassium alum, and the content of the potassium alum is in the range of 0.2 parts by mass or more and 6.0 parts by mass or less with respect to 100 parts by mass of the total amount of the calcium alumate and the anhydrous gypsum. The fast-curing mortar composition according to any one of claims 1 to 7. The fast-curing mortar according to any one of claims 1 to 8, wherein the alum is contained as a mixture containing the inorganic powder and the alum in an amount in the range of 20:80 to 80:20 by mass ratio. Composition. Further, the amount of the short fiber composed of one or more of the organic short fiber and the carbon short fiber is in the range of 0.05% by mass or more and 0.3% by mass or less with respect to the total amount of the quick-hardening mortar composition. The fast-curing mortar composition according to any one of claims 1 to 9, which comprises. Further, any one of claims 1 to 10, wherein the re-emulsified powder resin is contained in an amount in the range of 0.5% by mass or more and 30% by mass or less with respect to the total amount of the quick-curing mortar composition. The fast-curing mortar composition according to the section. The rate according to any one of claims 1 to 11, wherein the silica fume is contained in an amount in the range of 1% by mass or more and 15% by mass or less with respect to the total amount of the fast-curing mortar composition. Hard mortar composition. Further, claim 1 to 12, wherein the synthetic polymer-based thickening water-retaining agent is contained in the range of 0.05% by mass or more and 5.00% by mass or less with respect to the total amount of the quick-curing mortar composition. The fast-curing mortar composition according to any one of the following items.