KR20120104179A - Cement admixture, process for producing same, and cement composition, mortar, and concrete each containing the admixture - Google Patents

Abstract

The cement admixture of the present invention is a granulated product comprising cement and water as a binder material for granulation treatment and kneading to a crack self-healing material, and containing a crack self-healing material as a main component, and the crack self-healing material is a layered silicate mineral ( Aluminosilicates, magnesium silicates), crystalline and amorphous silicate minerals (aluminosilicates), calcium phosphates, compounds and minerals with carbonate groups, compounds containing lithium and minerals, compounds containing magnesium and minerals, containing fluorine At least one or more selected from the group consisting of a compound which is reactive, a material having a posoranity, a material having a latent hydraulic property, a material containing an expandable or non-plasticized material containing an expanded material, a material containing calcium oxide, and cement, and mixed at an arbitrary mixing ratio. will be.

Description

Cement admixtures and methods for preparing the same, and cement compositions, mortars and concrete including the admixtures thereof, CEMENT ADMIXTURE, PROCESS FOR PRODUCING SAME, AND CEMENT COMPOSITION, MORTAR, AND CONCRETE EACH CONTAINING THE ADMIXTURE

The present invention relates to a cement admixture, a method for producing the same, and a cement composition including the admixture, mortar, and concrete, and in particular, a cement admixture having self-healing performance against cracks, a method for producing the admixture, and a cement including the admixture. It relates to the composition, mortar and concrete.

Mortar and concrete used for construction of construction or civil engineering structures include cement, water, aggregate, and the like, and have a property of curing by a hydration reaction. The mortar and concrete after this hardening tended to be easily cracked due to stress or volume change due to temperature change, drying, or the like.

When such a crack occurs, water easily penetrates through the mortar or the crack of concrete, causing leakage, etc., and also causing problems such as deterioration of durability of the structure and deterioration of aesthetics.

In addition, for example, in the case of underground structures, water leakage due to cracking becomes a problem. In this case, since the repair work of cracking is difficult, the cost becomes relatively expensive.

Conventionally, measures have been taken to repair the filler by injecting the filler after the occurrence of the crack, or to apply watertight or water-proof holes to the mortar or concrete so as not to affect the structure even if the crack occurs. Is being taken.

However, the above-mentioned countermeasures such as repairing, waterproofing holes, and watering holes inevitably lead to an increase in cost, a prolongation of the construction period during construction of the structure, and the like.

Self-healing concrete is being developed that can maintain the exponential performance and durability even when the above-mentioned repair, waterproofing, exponent, etc. are not performed, and can repair itself even if a crack occurs (for example, See Patent Documents 1, 2, 3, 4).

However, in the self-healing concrete as described above, satisfactory crack self-healing performance is not obtained, but further improvement in exponential performance after cracking is required.

Moreover, when it is used for a building structure, not only a short period after pouring, but also when the crack generate | occur | produces after a long time passes, it is also required to be able to exhibit sufficient self-healing property.

In addition, in the above-mentioned Patent Document 4, a material having a self-healing performance (alumino silicate, magnesium silicate, carbonate, calcium oxide, expander, etc.) is added to concrete, and the concrete itself actively cracks at the time of crack generation by using the chemical action. Although a technique for curing the cure has been proposed, materials having such self-healing properties have high absorbency, swelling, or reaction activity with water, and when kneaded in concrete as it is, the slump of the concrete is lowered. Inevitably, there is a problem such that the condensation of concrete is remarkably delayed or the manufacturing cost is increased.

Patent Document 1: Japanese Patent No. 3658568 Patent Document 2: Japanese Patent Publication No. 2005-239482 Patent Document 3: Japanese Patent Publication No. 2007-332010 Patent Document 4: Japanese Patent Application Publication No. 2008-33548

The object of the present invention is that when the crack self-healing material is mixed with concrete, it does not adversely affect the flash properties such as deterioration of the slump, and maintains the crack self-healing performance until the crack occurs in the concrete. Cement admixture and its production method capable of forming concrete capable of greatly improving the long-term durability of concrete by sustaining the crack healing ability of the concrete over a long period of time, and a cement composition comprising the admixture, mortar and To provide concrete.

In order to achieve the said subject, the cement admixture of this invention is a granulated material which adds and knead | mixes cement and water as a binder material for granulation processing to a crack self-healing material, and contains a crack self-healing material as a main component, It is cement admixture.

Suitably, in the cement admixture of the present invention, the crack self-healing material has a layered silicate mineral (aluminosilicate, magnesium silicate), crystalline and amorphous silicate minerals (aluminosilicate), calcium phosphate, and carbonic acid groups. Compounds and minerals, compounds and minerals containing lithium, compounds and minerals containing magnesium, compounds containing fluorine, materials having reactivity with pozzorans, materials containing latent hydraulic properties, materials containing expansive or non-plastic expanding materials, calcium oxide It is a cement admixture, characterized in that at least one or more types are selected from the group containing materials and cement, and mixed by arbitrary mixing ratios.

Moreover, the particle diameter of the said granulated material is in the range of 0.1-15 mm, It is a cement admixture.

Moreover, it is a cement admixture characterized by the above-mentioned granulated material in which order material is contained. More preferably, the cement admixture is a cement admixture, characterized in that the order material is an organic compound of a silicified compound and / or a fatty acid having 12 or more carbon atoms.

More preferably, in the cement admixture of the present invention, the cement admixture further comprises a fiber and / or a water reducing agent.

In the method for producing a cement admixture of the present invention, in the crack self-healing material, cement as a binder material for granulation treatment is 5 to 200% by weight with respect to the self-healing material and water is 10 to 100% by weight with respect to the self-healing material. It is a manufacturing method of the cement admixture which adds and knead | mixes, and performs the granulation process of the obtained kneading material at least 1 time, and produces a granulated material.

Suitably, in the manufacturing method of the cement admixture of the said invention, it is the manufacturing method of the cement admixture characterized by performing at least 1 time order treatment to the granulated material after granulation process.

The cement composition of this invention contains the cement admixture of the said this invention, and a cement, It is a cement composition characterized by the above-mentioned.

In addition, the mortar or concrete of this invention is a mortar or concrete characterized by containing the cement admixture of the said invention, cement, water, and aggregate.

Advantageous Effects of Invention The present invention provides a cement admixture capable of imparting excellent self-healing properties to mortar and concrete, and capable of maintaining this self-healing property well over a long period without impairing the fluidity of the mortar and concrete. It becomes possible. In addition, including such cement admixtures, it is possible to provide a cement composition having a high self-healing property and a long and good self-healing property and a mortar and concrete comprising the same.

Hereinafter, although this invention is demonstrated based on suitable embodiment, it is not limited to these.

The cement admixture of the present invention is a cement admixture which is a granulated product which is kneaded by adding cement and water as a binder material for granulation treatment to a crack self-healing material and containing the crack self-healing material as a main component.

The self-healing material is a material having high absorption or swellability or high reaction activity with water, and is a layered silicate mineral (aluminosilicate, magnesium silicate), a crystalline or amorphous silicate mineral (aluminosilicate), calcium phosphate, carbonic acid group. Compounds or minerals, compounds containing lithium, or minerals, compounds containing magnesium or minerals, compounds containing fluorine, materials having responsiveness to pozzorans, materials having latent hydraulic properties, materials containing expansive or non-plastic expanding materials, oxidation At least 1 type or more can be selected from the group containing the material containing calcium and cement, and can be mixed and used in arbitrary mixing ratios.

Here, in this invention, "high reaction activity with water" means having properties, such as high solubility in water, which hydrates with water.

Examples of the layered silicate minerals (aluminosilicates, magnesium silicates) include talc belonging to the talc-pyrophyllite group of kaolinite, halosite, dicite, nacrite, audilite and clay minerals belonging to the kaolin group of clay minerals. ), Willemite, kerolite (talc with poor crystallinity), pimelite (willemrite with poor crystallinity), pyrophyllite (saltstone), saponite, hectorite, soco of clay minerals of clay mineral Masco belonging to the mica family of octahedral vermiculite, octahedral vermiculite and clay mineral belonging to the vermiculite family of knight, stevensite, swin holdite, montmorillonite, Weidelite, nontronite, volconscoite, clay mineral Bite (Dolomite), Floroite (Gill Mica), Annanite (Iron Mica), East Knight, Ciderlopite Tetraferry Iron It belongs to the interlaminar mica group of wool, polysilicate, ceradonite, iron ceradonite, iron aluminoseradonite, alumino ceradonite, branch mica, soda mica, celite, and clay minerals. Clintonite, Chamonixite, Penanite, which belongs to the Clintonite, Kinoshita, Hideunite, Pearl Mica, and Clay minerals of clay minerals of illite, green rock, brahmarite, warnesite, clay mineral Tight, nimite, veyrylclaw, donbasite, cookate, sudoite.

Among these layered silicate minerals (aluminosilicate, magnesium silicate), in particular, montmorillonite ((Na, Ca) _0.33 (Al, Mg) 2 Si ₄ 0 ₁₀ (OH) ₂ nH ₂ 0, n = negative), talc ( The use of talc, 3MgO-4SiO ₂ -H ₂ O) is preferred, and among montmorillonite, Na-bentonite, Ca-bentonite, acidic clay, attapalzite (pargolskate, Mg ₅ Si ₈ 0 ₂₀ (OH) ₂ ( OH ₂ ) ₄ ? H ₂ O, but part of Mg is substituted with Al), Sepiolite (Mg ₈ Si ₁₂ 0 ₃₀ (OH ₂ ) ₄ (OH) ₄ ~ 6 ~ 8H ₂ 0), the use of swelling It is especially preferable because it is excellent in the self-healing performance of cracks caused by the action.

In addition, the layered silicate mineral (aluminosilicate, magnesium silicate) can use the thing of the general industrial grade grind | pulverized about 0.01-1 mm in particle size.

In addition, the layered silicate mineral may be a mixture of the above-described minerals singly or in any combination and in any mixing ratio.

It is preferable that the layered silicate mineral is contained in the cement composition in an amount of 5 to 50% by weight in terms of expressing good self-healing performance of cracks.

As the crystalline or amorphous silicate mineral (aluminosilicate), the crystalline silicate mineral (aluminosilicate) is a clinoptilolite (saphtylol zeolite) belonging to zeolite (zeolite), mordenite Artificial algae obtained by adding a strong alkaline aqueous solution such as sodium hydroxide to natural zeolites such as (morden zeolite), lomontite (tablet stone), twillstone, and soda zeolite, synthetic (artificial) zeolite, and fly ash (coal). (Modified) zeolite etc. are mentioned. As an amorphous silicate mineral (aluminosilicate), arophen (Al ₂ 0 ₃ ? NSiO ₂ ? NH ₂ 0, n = 1 or more), imogolite (Al ₂ 0 ₃ ? SiO ₂ ? 2H ₂ 0), Shingerite etc. can be mentioned.

Among these crystalline or amorphous silicate minerals (aluminosilicates), the use of imogolite contained in natural alkano inexpensive and volcanic ash is preferable.

In addition, since the crystalline or amorphous silicate mineral (aluminosilicate) may have some expansion reactivity, in order to avoid popping out of the mortar cured body and the concrete cured body, the general industrial grade pulverized to about 0.01 to 1 mm in particle size is used. Can be used.

As the crystalline or amorphous silicate mineral, a mixture of the above exemplified minerals singly or in any combination and in any mixing ratio may be used.

It is preferable that 5-50 weight% of crystalline or amorphous silicate minerals are contained in a cement composition in the point which expresses favorable self-healing performance of a crack.

Examples of the calcium phosphate include Ca (H ₂ PO ₄ ) ₂ (first calcium phosphate), CaHPO ₄ (second calcium phosphate), Ca ₃ (PO ₄ ) ₂ (third calcium phosphate), bone ash (calcium phosphate = Ca _3). (PO ₄ ) ₂ ) and the like.

Among these calcium phosphates, CaHPO ₄ (secondary calcium phosphate) reacts with calcium hydroxide produced as a hydrate of cement minerals or the layered silicate mineral (magnesium silicate) in mortar and concrete containing a cement composition, Ca ₅ (PO ₄ ) ₃ (OH) (hydroxyapatite = hydroxyapatite) with high binding strength, Ca ₁₈ Mg ₂ H ₂ (PO ₄ ) ₁₄ (witrokite), tricalcium phosphate, calcium hydrogen phosphate dihydrate, phosphoric acid It is especially preferable because calcium phosphate compounds such as calcium anhydride, amorphous calcium phosphate, and calcium phosphate can be formed to form dense hydrates in cracked portions.

In addition, it is preferable to use the thing of the general industrial grade grind | pulverized about 0.01-1 mm in particle diameter, and calcium phosphate can also use what mixed the above-mentioned mineral individually or in arbitrary combinations, and in arbitrary mixing ratios. .

It is preferable that calcium phosphate is contained in 5 to 50 weight% in a cement composition from the point which expresses favorable self-healing performance of a crack.

As the compound or mineral having the carbonate group, a metal carbonate is suitable, for example, Li ₂ CO ₃ (lithium carbonate), Na ₂ CO ₃ (sodium carbonate), K ₂ CO ₃ (potassium carbonate), MgCO ₃ (carbonated acid) Magnesium), LiHCO ₃ (sodium bicarbonate), NaHCO ₃ (sodium bicarbonate), KHCO ₃ (potassium bicarbonate), Mg (HCO ₃ ) ₂ (magnesium bicarbonate), and the like.

Examples of compounds having these acid groups, an Li ₂ CO ₃ (lithium carbonate), is especially preferred because of its characteristics of repairing cracks in the concrete around.

As the compound or mineral having a carbonic acid group, it is preferable to use a general industrial grade that is finely pulverized to a particle size of 0.01 to 0.1 mm, and the compounds or minerals exemplified above alone or in any combination and in any mixing ratio. You may use the mixture.

It is preferable that the compound and mineral which have a carbonate group contain 1-10 weight% in a cement composition from the point which expresses favorable self-healing performance of a crack.

Examples of the compound or mineral containing lithium include Li ₂ CO ₃ (lithium carbonate), LiHCO ₃ (lithium carbonate), Li ₂ 0 (lithium oxide), LiOH (lithium hydroxide), LiOHH ₂ O (lithium hydroxide- Hydrate), Li ₂ SO ₄ -H ₂ O (lithium sulfate-hydrate), LiAlO ₂ (lithium aluminate), LiHSO ₄ (lithium sulphate), Li ₂ SO ₃ -nH ₂ 0 (lithium sulfite n hydrate, n = Negative), LiNO ₂ (lithium nitrite), LiNO ₃ (lithium nitrate), Li ₃ PO ₄ (lithium phosphate), (LiPO _3n ) _n (lithium phosphate, n = negative), Li ₂ HPO ₄ (lithium phosphate) , LiH ₂ PO ₄ (dihydrate lithium phosphate), Li ₃ P (lithium triphosphate), Li ₂ SiO ₃ (lithium metasilicate), Li ₄ SiO ₂ (lithium orthosilicate), Li ₄ 0 ₄ Si (lithium silicate), HCOOLiH ₂ O (lithium formate-hydrate), Li ₂ C ₂ 0 ₄ (lithium oxalate), Li ₃ (C ₆ H ₅ 0 ₇ ) -4H ₂ O (lithium citrate tetrahydrate), Li ₂ (C ₄ H ₄ 0 ₆ ) H ₂ O (lithium tartarate-hydrate), CH ₃ COOLi (lithium acetate), C ₂ H ₄ (COOLi) ₂ (lithium succinate), Li (C ₃ H ₅ 0 ₃ ) (lithium lactate), C ₆ H ₅ COOLi (Lee acid ), C ₁₇ H ₃₃ COOLi (oleic acid lithium), C ₁₇ H ₃₅ COOLi (other industrial lithium compounds such as stearic acid, lithium), swallowtail light (open feldspar = LiAlSi ₄ 0 _10), spokes jyumen (Patricia pyroxene = LiAlSi ₂ 0 ₆ ), Lithium-containing minerals such as Lyphidorite (Lysia mica = K (Li, Al) ₃ (AlSi ₃ 0 ₁₀ ) (OH, F) ₂ ), Amblgonite, Montebrasite, Bikitaite, etc. Can be.

It is preferable to use the general industrial grade thing which grind | pulverized these lithium containing compounds or minerals about 0.01-1 mm in particle size, and it is expensive, when it considers the self-healing rate of the crack which generate | occur | produced in mortar and concrete, although it is expensive The use of this high lithium carbonate or lithium nitrite is preferred.

On the other hand, in order to reduce the manufacturing cost and secure self-healing performance over an extremely long period of time, lithium-containing minerals such as petarite (follite) and spozumen (lysia fluoride), which are low in lithium content but inexpensive and have pozzoran reactivity. The use of is preferred.

In addition, as a compound or mineral containing these lithium, the compound or minerals exemplified above may be used singly or in any combination and in any mixing ratio.

It is preferable that the compound and mineral containing lithium contain 5 to 50 weight% in a cement composition from the point which expresses the favorable self-healing performance of a crack.

Examples of the compound or mineral containing magnesium include MgCO ₃ (magnesium carbonate), MgO (magnesium oxide = magnesia, pericles), Mg (OH) ₂ (magnesium hydroxide = brucite), MgSO ₄ (magnesium sulfate), Mg (NO ₂ ) ₂ (magnesium nitrite), Mg (NO ₃ ) ₂ (magnesium nitrate), 2MgO ₃ SiO ₂ ? NH ₂ 0 (magnesium silicate, n = negative), Mg ₆ Al ₂ (CO ₃ ) (OH) ₁₆ In addition to industrial magnesium compounds such as? 4H ₂ 0 (hydrotalcite), dolomite (high lime, CaCO ₃ ? MgCO ₃ ) containing a large amount of magnesium, magnesite (active clay, main component = MgCO ₃ ), olive rock = olive stone ( Two knights, olivine sand, Paul Stephen Wright sand, the night sands, such as principal component _{= (Mg, Fe) 2 SiO} 4), serpentinite the _{(3MgO? 2SiO 2? 2H 2} 0, some brucite = Mg (OH) ₂ ), Hornblende (Mg ₇ (Si ₄ 0 ₁₁ ) ₂ (OH) ₂ , but not including asbestos = asbestos), ore, loosened ore (enstatite = Mg ₂ Si ₂ 0 ₆ ), Calcite (CaMgSi ₂ 0 ₆ ), collingite (Mg ₁₀ Fe ₂ CO ₃ (OH) ₂₄ 2H ₂ 0), sjogrenite (Mg ₆ Fe ₂ (OH) ₁₆ CO ₃ 4H ₂ 0), pyro Light _{(Mg 6 Fe 2 (OH)} 16 CO 3? 4H 2 0), Brugg nateglinide light _{(Mg 6 Fe (OH) 13} CO 3? 4H 2 0), Ness kweho nitro (MgCO _3? 3H ₂ 0), etc. Magnesium-containing slag such as magnesium-containing minerals, ferronickel slag refrigerant which is a by-product of ferrotic refining, and ferronickel slag fine aggregate for concrete aggregate conforming to Japanese Industrial Standard JIS A 5011-2. Magnesium containing refractory materials, such as a light brick and magsite brick, etc. are mentioned.

In order to avoid popping out the mortar hardened | cured material and the concrete hardened | cured material, it is preferable to use the thing grind | pulverized about 0.01-1 mm in particle | grains containing these magnesium, and to emphasize the self-healing rate of the crack which generate | occur | produced in the hardened mortar and hardened concrete When used, magnesium carbonate and magnesium hydroxide having high magnesium content are preferable.

On the other hand, in order to reduce manufacturing cost, although magnesium content is low, the use of the mineral, slag, and refractory which contain extremely cheap magnesium is preferable.

Moreover, it is preferable to use what grind | pulverized the particle size of 0.1 mm or less in order to avoid the pop out of the hardened mortar and hardened concrete body.

These magnesium-containing compounds and minerals may be those obtained by mixing the above-described compounds or minerals singly or in any combination and in any mixing ratio. It is preferable that 5-50 weight% of compounds containing magnesium and a mineral are contained in a cement composition from the point which expresses favorable self-healing performance of a crack.

The Examples of the compound containing the fluorine, Na ₂ PO ₃ F (sodium monofluorophosphate), LiF (lithium _{fluoride), MgSiF 6? 6H 2 0} ( figures magnesium fluoride), Na ₂ SiF ₆ (figures sodium fluoride), etc. Can be mentioned.

These fluorine-containing compounds react with self-healing materials containing calcium hydroxide and other calcium, which are produced as hydrates of cement minerals in mortars and concretes containing cement compositions, and are fluoroapatite, calcium fluoride, and silicides. He creates insoluble salts such as calcium to heal the cracks. These fluorine-containing compounds may be used those obtained by mixing the above-described compounds alone or in any combination and in any mixing ratio.

It is preferable that the compound containing fluorine is contained 5 to 50 weight% in the point which expresses the favorable self-healing performance of a crack in a cement composition.

Examples of the material having the pozzoran reactivity include silica-like fine powder recovered during the manufacture of fly ash (coal material), silica fume (fumed silica), silica fused powder recovered during electrolytic zirconia, silica glass such as optical fiber, metal silicon ( Synthetic silica-like powder produced by burning (oxidizing) Si and silicon), precipitated silica synthesized by adjusting the pH of the silica-like fine powder synthesized by vapor phase reaction in a high-temperature hydrogen salt and the aqueous solution of sodium silicate. or silica gel, rice hulls or ash, kaolin mineral of byeojip (kaolinite _{= Al 2 0 3? 2SiO 2} ? 2H 2 0, di kite _{= Al 2 0 3? 2SiO 2} ? 2H 2 0, halloysite = Al ₂ 0 ₃ ? 2SiO ₂ ? 4H ₂ 0, etc.), and fired clay (e.g. waste, waste brick, waste pottery, waste pottery, etc.) or steelmaking Occurring Silica, such as blast furnace fume; artificial pozzo eggs and silas, siliceous clay, tuff (such as rhyolite tuff, zeolitic tuff, etc.), diatomaceous earth, acidic volcanic rocks, and volcanic ash, which have high content of silicon dioxide (SiO ₂ ) Natural pozzolan with high silicon (SiO ₂ ) content, etc. are mentioned.

The use of inexpensive and easy-to-use fly ash (coal material) is preferable as the material having such pozzo reactivity, and as the fly ash, Class I standard product or II class specified in Japanese Industrial Standard JIS A 6201 "Fly Ash for Concrete" Standard products, type III standard products, type IV standard products, classification fly ash adjusted to a specific particle size (particle size distribution) with a maximum particle diameter of about 10 to 20 μm, and a high calcium type fly ash containing 10 wt% or more of CaO. . Among these, the use of high or low calcium fly ash containing 10 wt% or more of Class I or II standards conforming articles, classification fly ash, or CaO having less impurities is more preferable. The high calcium type fly ash containing 10 weight% or more is especially preferable because pojoran is highly reactive.

As the material having pozzoran reactivity such as fly ash or the like, a mixture of the above-described materials alone or in any combination and at any mixing ratio may be used.

It is preferable that 5-50 weight% of materials which have pojoran reactivity, such as a fly ash, are contained in a cement composition from the point which expresses favorable self-healing performance of a crack.

As said latent hydraulic material, the blast furnace slag which is a by-product at the time of steelmaking is mentioned. The blast furnace slag fine powder 4000 standard product, the blast furnace slag fine powder 6000 standard product, the blast furnace slag fine powder 8000 standard product, or JIS A 5011 which is stable among blast furnace slag quality, and which is easy to obtain, and is specified in the Japanese Industrial Standard JIS A 6206 `` blast furnace slag fine powder for concrete ''. -1 It is preferable to use a pulverized blast furnace slag aggregate or blast furnace slag fine aggregate specified in "Slag Aggregate for Concrete-Part 1: Blast Furnace Slag Aggregate" having a particle size of 0.01 to 1 mm.

As the material having these latent hydraulic properties, those obtained by mixing the above-described materials alone or in any combination and in any mixing ratio may be used.

It is preferable that the material which has latent hydraulic property is contained 5 to 50 weight% in the point which expresses the favorable self-healing performance of a crack in a cement composition.

Examples of the expandable or non-plastic expandable component-containing material include commercially available ethringite-based (calcium sulfo aluminate) expandable materials, quicklime-based expandable materials, ethrinite quicklime composite-based expandable materials, and anne = calcium sulfoaluminate (an active ingredient of the expandable material). 3CaO ₃ Al ₂ 0 ₃ -CaSO ₄ ), cement lime, or cement, non-plastic expansion material containing cement (CaO), glass gypsum (CaSO ₄ ), and materials containing gypsum, Irwin, calcium oxide, respectively And mixing at a combination ratio and a mixing ratio, and not firing after mixing). Among these expanding materials or non-small expansion material component-containing materials, it is preferable that the quality is stable and meet the specifications of Japanese Industrial Standard JIS A 6202 " Expansion Material for Concrete ". In addition, these intumescent materials may use a mixture of the above-described swelling material or non-plastic swelling material component-containing material alone or in any combination and in any mixing ratio.

It is preferable that the expansion material or the non-plastic expansion material component-containing material is contained in the cement composition in an amount of 5 to 50% by weight in terms of expressing good self-healing performance of cracks.

Examples of the material containing calcium oxide (quick lime, CaO) include commercially available quick iron for sintering, quick converter for steelmaking, minor quickeners, quickeners for improving soil, and converters containing a large amount of calcium oxide as a by-product of steelmaking. Slag, electric furnace slag, etc. are mentioned.

In the present invention, the use of light (minor) quicklime having a lower digestion rate (hydration reaction rate) than normal quicklime is preferable. A material containing calcium oxide generates Ca (OH) ₂ by reaction with water, but this reaction is also volumetric expansion and also functions as an expansion agent.

In addition, by combining a compound having a carbonic acid group and a material containing calcium oxide, when a crack occurs in the mortar or concrete, a highly stable reactant such as calcium carbonate (calcite, CaCO ₃ ) is formed by the reaction of the positive component. It is possible to obtain more excellent crack self-healing performance.

Moreover, in order to avoid the pop out of the mortar hardened | cured material and the concrete hardened | cured material, the material containing these calcium oxides, It is preferable to use what was grind | pulverized to 0.1 mm or less of particle diameters, and it is single or arbitrary kinds and several calcium oxides from which a different particle diameter differs. You can also use

It is preferable that 1-10 weight% of materials containing calcium oxide are contained in a cement composition from the point which expresses the favorable self-healing performance of a crack.

As the cement, portland cement, other mixed cement, super fast-bound cement, and the like can be used without particular limitation. As portland cement, various portland cements, such as low heat, medium heat, normal steel, a crude steel, a sulfuric acid sulfate, etc. are mentioned, As a mixed cement, blast furnace cement, a fly ash cement, a silica cement, etc. are mentioned. Examples of the super fast-cement cements include alumina cement, 11 CaO ₇ Al ₂ O ₃ ? CaX ₂ system (X is a halogen element such as F) cement, and Arwin = calcium sulfoaluminate (3CaO ₃ Al ₂ O ₃ ? CaSO ₄ ) cement. Coarse-grained cement which adjusted the above-mentioned various cements to larger particle size (for example, maximum particle diameter = 100-300 micrometers, brain specific surface area = 500-2000cm <^2> / g) is mentioned.

Among these, inexpensive Portland cement is preferable, and in order to suppress the cracking of the mortar and the hardened body of concrete, low heat with high content of bellite (C ₂ S) in which the dry shrinkage (self shrinkage) of the hardened body of the mortar or concrete is reduced. Particular preference is given to the use of portland cement or medium heat portland cement. In addition, in the case of using a coarse cement adjusted to a larger particle size (for example, maximum particle size = 100 to 300 µm and brain specific surface area = 500 to 2000 cm ³ / g) of various cements, It is preferable because the long-term warming effect of self-healing performance is improved.

These cements may be used by mixing the above-described cement alone or in any combination and in any mixing ratio. It is preferable that the cement contains 5-50 weight% in a cement composition from the point which expresses favorable self-healing performance of a crack.

The granulated material of the cement admixture of the present invention is a granulated material containing a material obtained by mixing the crack self-healing material singly or in two or more kinds in an arbitrary ratio, but in producing the granulated material, a binder material for granulation Use Cement and water are used as a binder material for granulation.

As cement for the binder material for granulation, portland cement, other mixed cement, super fast-bound cement, etc. can be used without a restriction | limiting in particular. Examples of the portland cements include various types of portland cements such as low heat, medium heat, ordinary steel, crude steel, sulfuric acid sulfate, and the like, and mixed cements include blast furnace cement, fly ash cement and silica cement. Examples of the boundary cement include alumina cement, 11 CaO ₇ Al ₂ O ₃ ? CaX ₂ system (X is a halogen element such as F) cement, and Arwin = calcium sulfo aluminate (3CaO ₃ Al ₂ O ₃ ? CaSO ₄ ) cement. Can be.

Among these, inexpensive Portland cement is preferable, and in order to suppress the cracking of the mortar and the hardened body of concrete, low heat with high content of bellite (C ₂ S) in which the dry shrinkage (self shrinkage) of the hardened body of the mortar or concrete is reduced. Particular preference is given to the use of portland cement or medium heat portland cement.

The addition amount of the cement used as a binder material for granulation is suitably in the range of 5 to 200% by weight based on the self-healing material to be granulated.

If the amount of cement added is less than 5% by weight, the binder is insufficient and the strength of the granulated particles is considerably lowered. On the other hand, if the amount of cement exceeds 200% by weight, the binder becomes excessive and the strength of the granulated particles is too high. In addition, since the content of the self-healing material in the granulated material is low and the self-healing performance of cracks generated in the mortar or concrete is not sufficiently obtained, it is unsuitable.

The water for the binder material for granulation is not particularly limited as long as it does not contain organic matter, chloride ions, sodium ions, potassium ions, or the like, which adversely affect the hydration reaction of cement or the hardened body of mortar and concrete. Industrial water, groundwater, river water, rainwater, distilled water, high purity water for ultra chemical analysis (ultra pure water, pure water, ion exchanged water) and the like can be used.

Among these, use of tap water or industrial water which is inexpensive and stable in quality is preferable. The addition amount of the water used as a binder material for granulation is suitable for the inside of the range of 10 to 100 weight% with respect to the self-healing material used for granulation.

If the amount of water added is less than 10% by weight, the particles to be granulated do not aggregate due to lack of water, and granulation is impossible. On the other hand, when the amount of water exceeds 100% by weight, water becomes excessive and becomes impossible to granulate. Inadequate

As for the cement admixture of this invention, order processing is given to the said granulated material suitably, and the order material is contained.

The material for order treatment used when ordering the cement admixture granulated material of the present invention is an aqueous solution of a silicified compound or an organic solvent solution of 12 or more fatty acids.

Silicon as the fluoride compound, may be used in the figures as magnesium fluoride _{(MgSiF 6? 6H 2 0)} , silicon calcium fluoride, silicon fluoride, potassium silicon fluoride, sodium fluoride, silicon has a high solubility in water, such as lithium fluoride, a general industrial grade .

Especially, magnesium silicate is especially preferable because it is excellent in the characteristic which repairs the crack of concrete.

It is preferable to melt | dissolve these silicic-fluoride compounds for order-processing, in tap water, pure water for chemical analysis, etc., and to prepare and use so that it may become an aqueous solution of 10-50 weight%.

The silicified compound may be used singly or in any combination or in any mixing ratio.

As fatty acids having 12 or more carbon atoms (= higher fatty acids), lauric acid (dodecanoic acid), myristic acid (tetradecanoic acid), pentadecylic acid (pentadecanoic acid), palmitic acid (hexadecanoic acid), and palmitoyl acid (9-hexadecenoic acid), margaric acid (heptadecanoic acid), stearic acid (octadecanoic acid), oleic acid (cis-9-octadecenoic acid), baxenic acid (11-octadecenoic acid), linoleic acid (cis? Cis) -12-12 octadecadiic acid), linolenic acid (octadecatenic acid), tuberculostearic acid (nanodecanoic acid), behenic acid (docosanic acid), lignoserine acid (tetradocoic acid), nerbonic acid Saturated fatty acids or unsaturated fatty acids, such as (cis-15- tetradocoic acid), serotonic acid (hexadocoic acid), montanic acid (octadocoic acid), and meric acid, are mentioned, and the thing of general industrial grade can be used.

Especially, stearic acid (octadecanoic acid) is especially preferable because it is inexpensive and easy to obtain. In addition, fatty acids having less than 12 carbon atoms are not preferable because they have many malodors and their melting points are too low (liquid at room temperature).

Fatty acids having 12 or more carbon atoms for these orders are preferably dissolved in an organic solvent such as ethyl alcohol, methyl alcohol or acetone so as to have a saturated concentration.

The fatty acid having 12 or more carbon atoms may be used singly or in any combination or in any mixing ratio.

More suitably, it is preferable that the granulated material of the cement admixture of the present invention further comprises a fiber and / or a water reducing agent.

The fiber material used for the cement admixture assembly of the present invention is not particularly limited except for a fiber material harmful to the human body, such as asbestos (asbestos), and can be used with any material such as polymer fiber, inorganic fiber, metal fiber, and the like. .

Examples of the polymer fibers include vinylon polymer fibers, polypropylene polymer fibers, polyvinyl alcohol polymer fibers, polyacrylic polymer fibers, polyacrylonitrile polymer fibers, polyamide polymer fibers, polyurethane polymer fibers, cellulose polymer fibers, Rayon type polymer fiber, an acetate type polymer fiber, etc. are mentioned.

Examples of the inorganic fibers include alkali-resistant glass fibers, rock wool, slag wool, wool lusterite fibers, basic magnesium sulfate fibers, potassium titanate fibers, attapalgitite (palgolgolite), sepiolite, PAN-based carbon fibers, and pitch-based carbon fibers. Can be mentioned. Examples of the metal fiber include steel fibers, high-tensile steel fibers, and stainless fibers.

Among these, use of inexpensive vinylon type polymer fiber and polypropylene type polymer fiber is preferable as organic fiber. As the inorganic fiber, the use of rock wool, slag wool, wool lusterite fiber, basic magnesium sulfate fiber, potassium titanate fiber, atapalzite (palgolgolite), or sepiolite with high affinity with a self-healing material or cement is preferable. Particular preference is given to the use of basic magnesium sulfate fibers, attapalzite (paligolskyte), and sepiolite having a composition (component) of self-healing materials (aluminosilicate, magnesium silicate).

It is preferable that the shape of the fiber material is 15 mm or less in fiber length and 0.1 mm or less in fiber diameter, and the fiber length is preferably about the same length as the particle diameter of the cement admixture self-healing material granulated material of the present invention.

The fiber material may be used alone, or a plurality of fibers having different materials and shapes may be mixed and used in any combination and mixing ratio.

It is preferable that the fiber material contains 0.1-5 volume% in a cement composition from the point of strength.

By adding the fiber material to the cement admixture material of the present invention at the time of granulation, the strength of the cement admixture obtained is increased and the concrete to which the cement admixture of the present invention is added is cured. When the crack occurs, the particles of the self-healing material granules present in the cracked surface or the cracked surface are likely to crack (anchor effect), thereby increasing the self-healing speed of the crack.

In addition, since the fiber material becomes a precipitation site (nucleus) of the self-healing product between the cracked surfaces, an effect of easily self-healing even in cracks larger than the crack width at which healing can be expected is usually obtained.

Moreover, as a water reducing agent, a well-known thing can be applied as a water reducing agent used for concrete, such as a liquid or powder type water reducing agent, an AE water reducing agent, a high performance water reducing agent, and a high performance AE water reducing agent.

The polycarboxylic acid-based water reducing agent can suppress the deterioration of the fluidity of the concrete accompanying the addition of the aluminosilicate having the above-mentioned swelling property, and is also suitable from the viewpoint of maintaining the fluidity and improving the workability.

In addition, by including a water reducing agent, the hydration reaction of the cement-based material included in the self-healing material granulated material can be delayed, so that the self-healing performance of mortar and concrete can be maintained for a longer period of time.

The water reducing agent is preferably 0.1 to 3.0% by weight in the cement composition. In addition, a water reducing agent is not contained as a cement admixture but may be added when preparing concrete using a cement composition as mentioned later.

In the method for producing a cement admixture of the present invention, in the crack self-healing material, cement as a binder material for granulation treatment is 5 to 200% by weight with respect to the self-healing material and water is 10 to 100% by weight with respect to the self-healing material. It adds and knead | mixes, and performs the granulation process of the obtained kneading material at least 1 time, and manufactures a granulated material.

In this invention, the said binder material is mix | blended with the said crack self-healing material, Furthermore, a fiber material and a water reducing agent are added as needed, and the obtained mixed material is granulated uniformly by stirring and mixing. In addition, when the shell of the binder material is formed (coated) on the particle surface of the self-healing material at the time of granulation, the degree of ordering of the self-healing material is increased and the long-term warming effect of the self-healing performance is improved.

The granulation method (assembling device) used for the method of manufacturing the cement admixture of the present invention is not particularly limited as long as it can obtain a particle size and particle size distribution of a desired granulated product, and is a commercially available general kneading granulator and a wet extrusion granulator. , Cylindrical granulator, tilting electric stirring granulator, twin-screw granulator, disc pelletizer (fan pelletizer), fluidized bed granulator, swinging fluidized bed granulator and the like.

In particular, a kneading granulator, a wet extrusion granulator, a cylindrical granulator, a tilting electric stirring granulator, a twin-shaft granulator, a disk pelletizer (fan pelletizer), etc., which can be subjected to a large amount of granulation treatment in a short time, are preferable. And it is preferable to adjust the rotation speed of a granulator, the addition amount of cement which is a binder material, water, etc. so that it may become a desired particle diameter.

Moreover, the range of 0.1-15 mm is preferable, and, as for the particle size of the cement admixture granulated material of the granulated this invention, the range of particle size 0.5-5 mm is especially preferable.

In addition, the particle size distribution is not a problem even if it consists of granules of continuous particle size or single particle diameter. If the particle size of the granulated product is less than 0.1 mm, the improvement effect on the fresh properties of the concrete, the amount of the water reducing agent added, and the long-term warming effect of the crack self-healing performance of the concrete cannot be obtained. On the other hand, when the particle diameter of a granulated material exceeds 15 mm, since the self-healing material tends to be uneven in concrete, and the self-healing performance of a crack falls, it is unsuitable. In order to adjust to a desired particle size, classifiers, such as a general body (for example, JIS body), can be used.

In order to manufacture the cement admixture of the present invention, the self-healing material can be produced by repeating the granulation treatment one or more times and, if necessary, one or more treatments. In the granulation process, the self-healing material granules smaller than the desired particle size may be separated by stripping or the like, and then the binder material (cement and water) may be added again to carry out the granulation process and may be larger than the desired particle size. The self-healing material granulated material may be separated by shredding or the like, and then crushed to reduce the particle size. Furthermore, after crushing and making the particle size small, the binder material (cement and water) may be added again and granulation process may be performed.

It is preferable to repeat the granulation treatment one or more times, and if necessary, by repeating the order treatment one or more times, since the degree of ordering of the self-healing material is increased and the long-term warming effect of the self-healing performance is improved.

Moreover, suitably, in manufacturing the cement admixture of the said invention, order processing is performed at least 1 time to the granulated material after granulation process.

When the aqueous treatment method of the silicide compound mentioned above is used, the order treatment method prepares a density | concentration to 10-50 weight%, and apply | coats, impregnates, inject | pours, etc. the aqueous solution of this silofluoride compound with respect to the self-healing material granulated material. It is preferable to perform an order treatment by immersing a method or self-healing material granulated material in the aqueous solution of a silofluoride compound, and curing and drying after that.

The silicide compound reacts with calcium compounds, such as cement or calcium oxide, contained in the granules of the self-healing material, and is converted into poorly soluble compounds in water such as calcium silicate compounds, thereby densifying the surface and the interior of the granules of the self-healing material. , Order processing is carried out. The curing period in the order treatment is carried out at room temperature (about 20 ° C) for at least 24 hours, preferably about 72 hours, and then the drying is carried out at room temperature (about 20 ° C) at a temperature range of about 100 ° C.

It is preferable to use the usage-amount of the aqueous solution of a silofluoride compound about 5-20 weight% with respect to the granulation material of a self-healing material. On the other hand, in the case of using a fatty acid having 12 or more carbon atoms, it is dissolved in an organic solvent such as ethyl alcohol, methyl alcohol, propanol, butanol, acetone so as to have a saturation concentration, and the organic solvent solution is used for the self-healing material granulated product. It is preferable to perform the order treatment by immersing the self-healing material granulated product in the method of coating, impregnation, injection, or the like, and then evaporating and removing only the organic solvent.

The fatty acid having 12 or more carbon atoms reacts with calcium compounds, such as cement or calcium oxide, contained in the self-healing material granulated material, and is converted into a compound that is poorly soluble in water such as calcium salt (calcium soap) of the fatty acid, thereby making the surface of the self-healing material granulated material difficult. And the interior is densified, and the degree processing is performed. In the case of using an organic solvent solution of a fatty acid having 12 or more carbon atoms, the curing period in the order treatment is unnecessary, and it is dried at a temperature range of about 100 ° C. at room temperature (about 20 ° C.) to remove the organic solvent. It is preferable that the usage-amount of the organic-solvent solution of a C12 or more fatty acid uses about 1 to 10 weight% with respect to granulated self-healing material.

The order treatment is a method of applying, impregnating, or injecting an aqueous solution containing a silicified compound or an organic solvent containing fatty acids having 12 or more carbon atoms to a cement admixture, or a cement admixture assembly. You may repeat the order process to be immersed in the aqueous solution containing a fluorinated compound, or the organic solvent containing a C12 or more fatty acid twice or more times.

Moreover, you may perform combining these granulation process and order process arbitrarily 2 or more times. By repeating the granulation treatment and / or the order treatment two or more times, the fresh properties of the concrete to which the self-healing material granulated material is added improve the effect on the amount of the water reducing agent or the long-term warming effect of the crack self-healing performance of the concrete.

The cement composition of the present invention is a cement composition containing the cement admixture of the present invention and cement.

As cement for the cement composition in the present invention, portland cement, other mixed cements, ultrafast cement, etc. can be used without particular limitation. As portland cement, various portland cements, such as low heat, medium heat, normal steel, a crude steel, a sulfuric acid sulfate, etc. are mentioned, As a mixed cement, blast furnace cement, a fly ash cement, a silica cement, etc. are mentioned. As the initial velocity boundary cement, alumina _{cement, 11CaO? 7A1 2 0 3?} CaX 2 system can be given (X is a halogen element such as F) cement, Irwin = calcium sulfo aluminate-based cement or the like. Among these, inexpensive Portland cement is preferable, and low-heat Portland having a high content of non-lite (C ₂ S) in which the dry shrinkage (self-shrinkage) of the hardened body of mortar or concrete is reduced in suppression of the crack of the hardened body of mortar or concrete. Particular preference is given to the use of cement or medium heat Portland cement. Moreover, you may combine general cement admixtures, such as blast furnace slag fine powder, limestone fine powder, fly ash, silica fume, dihydrate gypsum, anhydrous gypsum, and hemihydrate gypsum as other components.

Cement admixtures of the present invention include cracked self-healing materials (layered silicate minerals (aluminosilicates, magnesium silicates)), crystalline and amorphous silicate minerals (aluminosilicates), calcium phosphates, compounds with carbonate groups, minerals and lithium. Compounds and Minerals Containing, Compounds and Minerals Containing Magnesium, Compounds Containing Fluorine, Materials Responding to Pozoranes, Materials with Potential Hydrophobicity, Materials Containing Expanding or Non-Inflatable Expanding Components, Materials Containing Calcium Oxide, Cement When at least one or more types are selected from the group of, and mixed at an arbitrary mixing ratio, the cement composition is added by kneading with cement and water as a binder material for granulation, and the granulated material is contained in the cement composition and applied as mortar and concrete. Excels in self-healing for these mortars and concretes Can, and also it makes it possible to maintain the self-healing property over a long period. It is not clear about this factor, but it is assumed as follows.

That is, the material which has self-healing property in the cement admixture of this invention produces | generates the hydrate which has expandability by the hydration reaction with water in a crack part, when a crack generate | occur | produces in mortar and concrete, The crack can be filled by In addition, layered silicate minerals (aluminosilicates, magnesium silicates) in cement admixtures produce and swell crystalline hydrates by hydration with water, and are combined with hydrates or eluting components produced from other self-healing materials. Insoluble precipitates can be formed in cracks. In the mortar and concrete including these, when water is submerged in the cracked portion, first, a layered silicate mineral (aluminosilicate, magnesium silicate) having swelling property is immediately swelled to form a void in the concrete first, Reduces the space where hydrates can precipitate.

Subsequently, crystalline and amorphous silicate minerals (aluminosilicate), calcium phosphate, compounds having a carbonic acid group and minerals, lithium-containing compounds and minerals, magnesium-containing compounds and minerals, and fluorine-containing compounds , Pozzo is a material that elutes from reactive materials, latent hydraulic materials, inflating materials or non-plastic inflating materials, calcium oxide, and cement-containing materials and moves to cracks by diffusion without depositing in mortar and concrete. It is thought that the outstanding effect of selectively filling a crack part can be exhibited by this. As a result, according to the mortar and concrete using the cement composition containing the cement admixture of this invention, even if a crack generate | occur | produces, a crack will fully be repaired for a long time and the exponential performance will be maintained favorable.

In addition, the mortar or concrete of this invention is the mortar or concrete containing the cement admixture of this invention, cement, water, and aggregate.

Aggregates used for mortar and concrete include fine aggregates and coarse aggregates. Here, what adds only fine aggregate as aggregate is called a mortar, and what added both coarse aggregate and fine aggregate as aggregate is usually called concrete.

Mortar and concrete of the present invention, as fine aggregate, land sand (mountain sand), sea sand, river sand, crushed sand, silica sand, blast furnace slag fine aggregate, ferronickel slag fine aggregate, electro-oxidized slag fine aggregate, copper slag fine aggregate, ferrochrome Fine aggregates, artificial lightweight aggregates, recycled fine aggregates, molten slag fine aggregates, and the like. Examples of coarse aggregates include land pebbles (mountain pebbles), sea pebbles, strong pebbles, crushed stone, blast furnace slag coarse aggregates, artificial lightweight aggregates, recycled coarse aggregates, and molten slag coarse aggregates.

In addition, coarse aggregates and fine aggregates can be distinguished according to normal classification (eg, vegetable classification). The amount of water contained in the concrete is preferably an amount of 25 to 60% by weight, more preferably 40 to 50% by weight, when the cement composition is 100% by weight.

When the amount of this water exceeds 60% by weight, a large amount of water may remain in the concrete after curing, and the strength may become insufficient, and the self-healing ability of the self-healing material in the cement admixture decreases. It may be difficult to maintain self-healing for a long time.

The content of the cement composition in the concrete are, for example, in the case of being classified as ordinary mortar as mentioned above. When the 1m, 300 ~ 1000kg per ³ and more preferably, is 400 ~ 800kg is more preferable. Moreover, in the case of what is normally classified as concrete, it is preferable in it being 200-700 kg per 1 m <^{3> of the} said concrete, and if it is 300-450 kg, it is more preferable. When the content of the cement composition is within this range, the solidification of the concrete by the cement composition occurs satisfactorily, and excellent strength can be obtained. In addition, unreacted self-healing materials and the like remain in the concrete, and excellent self-healing properties. At the same time, it is possible to maintain self-healing over an organ.

In addition, from the viewpoint of obtaining sufficient strength in such concrete, the content of the fine aggregate in concrete is preferably 1000 to 1700 kg per 1 m ³ , and more preferably 1200 to 1500 kg, in the case of being classified as mortar. desirable. In the case of being classified as the normal concrete, that is concrete 700 - 1000kg per 1m ³ is preferred, and more preferably is 800 - 900kg, The content of the coarse aggregate is, when the concrete 800 - 1100kg per 1m ³ and preferably, 850 to It is more preferable if it is 950 kg.

Such concrete can be obtained, for example, by adding the cement admixture to cement to form a cement composition, and adding water and aggregate to the cement to mix the cement. However, since the concrete of this invention should just contain the said cement admixture in the composition, for example, some components contained in a cement admixture are not included in a cement composition, but are added at the time of preparation of mortar and concrete. It may be done. Alternatively, the self-healing material assembly itself of the present invention may be replaced with a part of fine aggregate and / or coarse aggregate to be used as aggregate replacement. In the case of what is normally classified as mortar, the substitution amount in that case is preferable in it being 30-400 kg per 1m <^3> . Moreover, in the case of what is normally classified as concrete, it is preferable if it is 15-200 kg per 1m <^{3> of the} said concrete.

Concrete using the cement composition containing the cement admixture of the present invention having the above-described configuration, even if cracks have occurred after curing, is excellent in the property of recovering the index performance by itself, and can maintain such a property for a long time. Therefore, it is possible to apply extremely suitably to structures which are easy to generate leaks, for example, underground structures, tunnels, and the like, which are difficult to repair.

Example

Hereinafter, although an Example demonstrates this invention still in detail, this invention is not limited to such an Example.

[Materials used]

(1) Self-healing materials

Na-bentonite (Western Gel, Bentonite Industries, Wyoming, USA)

Talc (general purpose talc SSS, Nippon Talc company)

? Fly Ash (Fine Ash 20, manufactured by Yonden Business Co., Ltd., Fly Ash classified to a particle size of 20 μm or less, Class I conforming product of JIS A 6201)

Dicalcium Phosphate (Etin, Toyo Denka Co., Ltd., Feed, Made in China)

Lithium carbonate (high purity lithium carbonate for battery, product made in Honjo Chemical Co., pulverized product, Chile)

The five kinds of materials were weighed so as to be 10 kg in one batch at the blending ratio shown in Table 1 below to prepare a self-healing material.

[Table 1]

(2) binder material for assembly

Cement (Low Heat Portland Cement, Sumitomo Osaka Cement Co., Ltd.

         JIS R 5210 conformity product)

? Water: Tap water

(3) Ordering Materials

i) aqueous magnesium silicate solution

? Order materials: silicon fluoride, magnesium (Kanto Kagaku Co., Ltd., reagent MgSiF ₆ 6H ₂ 0?)

? Solvent: Tap Water

(Preparation method)

A water supply to be 10 liters the figures magnesium fluoride _{(MgSiF 6? 6H 2 0)} 3kg to prepare an aqueous magnesium fluoride dissolved silicon.

ii) stearic acid saturated ethyl alcohol solution

Order material: stearic acid (manufactured by Kantogagaku Co., reagent C ₁₇ H ₃₅ COOH)

Solvent: ethyl alcohol (Kantokagaku Co., reagent express C ₂ H ₅ 0H)

(Preparation method)

50 g = excess stearic acid (C ₁₇ H ₃₅ COOH) was mixed with 10 liters of ethyl alcohol and stirred sufficiently, an excess amount of stearic acid was precipitated, and a supernatant solution was aliquoted to prepare a stearic acid saturated ethyl alcohol solution.

(4) fiber material

Vinylon short fiber (Powerron RFCS7 * 6, product made by Kuraray Corporation, fiber length 6mm, fiber diameter 27㎛, density = 1.3 g / cm ³ )

(5) water reducing agent

? Polylic powder reducing agent (Mighty 21P, Chao's company, sodium methacrylate)

(6) cement for cement composition

Low-temperature portland cement (manufactured by Sumitomo Osaka Cement Co., JIS R 5210 compliant)

(7) Mortars and concrete materials

? Cement: Plain Portland Cement

          (Made by Sumitomo Osaka Cement,

JIS R 5210 compliant, density = 3.15 g / cm ³ )

Fine mortar for mortar: Standard sand for JIS R 5201

                    (Cement association, one bag = 1350 g)

? Concrete Aggregate Aggregate: Mount Sand, Chiba Prefecture

(Dry density = 2.55 g / cm ³ , absorption rate 2.1%)

? Gross aggregate: Sakuragawa from Ibaraki hard sandstone crushed stone 2005

(Dry density = 2.66 g / cm ³ , water absorption 0.6%)

? Water: Tap water

Concrete reducing agent: (manufactured by BASF, lignin sulfonic acid,

                      JIS A 6204 conformity product)

[Device used]

Stirring assembly device (product made in Taihei-Yokoki Co., Ltd., H.F mixer HF-50 type,

                 Rated capacity 50 liters)

Mortar mixer (for JIS R 5201)

Concrete mixer (made by Taihei Yokoko Co., Ltd., 2-axis compulsory dough mixer, SUPER DOUBLE MIXER SD-55, rated capacity 55 liters)

Digital microscope (product made from KEYENCE company, VHX-1000) for crack observation

[Preparation of Admixtures]

10 kg of said (1) self-healing materials were measured, it put in the said stirring granulation apparatus, and dry-mixed for 1 minute by low speed rotation. Thereafter, the low-temperature portland cement and (2) the binder material for assembling and water, and, if necessary, the vinylon fiber as the (4) fiber material and the polycal-based powder sensitizer as the (5) water reducing agent. 10 kg of the self-healing material added to the mixture was stirred at an outer capacity of the following Table 2 while being added little by little into the stirring granulator, and granulated so as to have a maximum particle diameter of about 15 to 20 mm over 3 minutes. The process was carried out.

The obtained granulated material was sealed in a bag made of polyethylene, and cured in a room temperature at 20 ° C. for 3 days to obtain a cement admixture as a granulated product.

Further, if necessary, and further after that, after immersion in an aqueous solution of the silicic fluoride compound for 1 day or in stearic acid saturated ethyl alcohol solution for 1 hour, and then the immersed granules are taken out and 3 at It dried over time and obtained the cement admixture.

Moreover, as shown in Table 2, when performing the said granulation process and order process several times as needed, the said process was repeated.

The granulated product thus obtained had a hole of 0.1 mm, 0.5 mm, 5 mm, and 15 mm, and the particle size ranged from 0.1 to 15 mm, 0.5 to 5 mm, less than 0.1 mm and more than 15 mm, as shown in Table 2. Each adjusted.

Experimental Example 1

Table 2 shows the results obtained by evaluating the cement admixtures (assemblies) of Examples 1 to 17 and Comparative Examples 1 to 9 prepared above.

(1) The quality of cement admixture assembly

The quality of granulation was determined by visual observation of the whole granulated material and the acceleration of ten granulated materials randomly extracted (hardness of a cement admixture).

◎ = very good (the surface is smooth by clean design, hardly crushed when compressed with fingers and fingers, powder hardly comes out), ○ = excellent (partly crushed when the surface is compressed by smoothness with fingers and fingers) Unstable, slightly powdery), ● = normal (usually spherical, irregular surface, half crushed, powdery when compressed with fingers and fingers), △ = slightly squeezed Unevenness, more than half of crushing when compressed with fingers and fingers, slightly more powder comes out, × = deteriorated (many of deformed spheres, uneven surface, mostly crushed with fingers and fingers, very powdery A lot)

In the case of the naked eye, it was determined that the closer to the spherical shape and the smaller the unevenness of the surface of the granulated particles, the better. In addition, in the case of acceleration, the higher the crush strength of the granules before and after curing (difficult to crush when compressed with fingers and fingers), and the higher the stability of the granules (with powder when compressed with fingers and fingers). Less = difficult to collapse), the better.

Absorption Stability of Cement Admixture Assembly

Promoting 10 visually and randomly extracted granules of the whole granules whether or not each cement admixture is immersed for 6 hours in 10 times (weight) of tap water of the cement admixtures and not expanded or destroyed by self-absorption. Absorption stability was determined by the hardness of the granulated material after absorption).

◎ = jump out (almost not inflating and collapsing), ○ = normal (expand or collapsing in part), × = fall (almost inflating or collapsing)

(Fluidity of mortar, crack self-healing performance of hardened mortar)

Each cement admixture is substituted with 25% by weight of ordinary Portland cement (manufactured by Sumitomo Osaka Chemical Co., Ltd.), and each cement composition is used. Furthermore, 450 g of the cement composition is Japanese Industrial Standard JIS R 5201 "Physics of Portland Cement. 1350 g of standard sand and 225 g of tap water for "Test Method" were added, and the mixture was kneaded with a mortar mixer in accordance with JIS R 5201.

Each mortar kneaded was immediately measured 15 mortar flows based on JISR 5201, and it was set as the evaluation of each mortar fluidity.

Mortar Liquidity

? A: 15 strokes over 200mm

? B: 15 strokes more than 150mm, less than 200mm

C: 15 strokes more than 100 mm, less than 150 mm

? D: Flow not measured

Next, each mortar which measured the said flow was returned to the batter bowl of a mortar mixer, and kneaded again for 30 second, and was then beaten to the plywood mold of 4 cm x 16 cm x 16 cm of internal dimensions, and the plate-shaped mortar hardening specimen was produced.

Each mortar hardened | cured material was sealed and cured at 20 degreeC constant temperature.

In each mortar cured body demolished on the 7th day, one crack of 0.2 to 0.3 mm in width was generated, and then immersed in a polypropylene batter (flat plate) with 2 liters of tap water, respectively, and curing in water at a room temperature of 20 ° C. Carried out.

Then, the crack formation part of the hardened | cured mortar was observed using the digital microscope (product number VHX-1000, the product made by Keyence Corporation) at the interval of 1 day, and the crack self-healing performance was evaluated.

Self-healing performance (mortar hardened body)

A: The crack is rapidly filled with the precipitate, and the chemical stability of the precipitate is extremely high.

? B: The cracks are slowly filled with precipitates, resulting in high chemical stability of the precipitates.

C: The crack is filled with a precipitate, but the chemical stability of the precipitate is not very high.

? D: No precipitates are filled in the cracks, and there is no self-healing effect of the cracks.

[Table 2]

From Table 2, in Examples 1 to 17 of the present invention, all of the cement admixture granulated material, the absorption stability, the mortar when added to the mortar (float) and the crack self-healing performance was good, In Comparative Examples 1-9 other than this invention, since the addition amount of cement or water was too small or excessive, granulation itself was impossible or the strength of the granulated material became too high, and the granulation state was defective. In addition, since the granulation or order treatment was insufficient, the absorption stability was also poor. Moreover, the mortar's fresh properties (fluidity) were remarkably low when added to mortar. It is also clear that the self-healing performance is low.

Test Example 2

[Crack Self-Healing Performance by Concrete Curing Body]

By using the cement admixtures (assemblies) obtained in Examples 18 to 22 and Comparative Examples 10 to 11, the concrete of 2 minutes using a biaxial forced dough mixer with 25 liters of one-batch dough mixture in the formulation of Table 3 below. Kneaded.

Next, the concrete specimens of the rectangular parallelepiped shape of 10 cm x 10 cm x 40 cm were produced using the concrete after the kneading | mixing.

The concrete specimens were stored in a sealed state at a constant temperature of 20 ° C. until 7 days of age, and externally restrained by PC steel bars.

In the seventh day, one crack was introduced into each concrete specimen. The crack was generated by applying a tensile force to each specimen. The crack width generated in the concrete specimen portion was fixed at 0.3 mm.

Table 3 shows the results obtained by applying the respective concrete specimens to the following evaluations.

(1) Evaluation of slump

Immediately after the completion of the concrete dough, the slump test was performed in accordance with Japanese Industrial Standard JIS A 1101 "Concrete Slump Test."

Slump Rating

The larger the value, the better the consistency (workability) of the fresh concrete.

It compares with the numerical value of the comparative example 11 (plane concrete).

(2) evaluation of exponentiality

After fixation of the cracks, a head of 1 m was given and water was always flowing between the cracks of the hardened concrete body, and the self-healing properties of the cracks were observed. The equal gradient at this time was 10 m / m. In this evaluation, in addition to the evaluation of the exponential obtained by measuring the above-mentioned permeability in (i) the constant permeability state, (ii) the degree of permeation was observed under the microscope under the constant permeability state, and the extent to which the crack width decreased. Evaluated.

Exponential evaluation

? A: When the permeation amount is less than one-fifth of the initial permeation amount in 7 days

? B: In seven days, the permeability is greater than one-fifth of the initial permeation rate,

     When it becomes less than tenth

? C: Permeability is greater than tenths of initial permeation rate in seven days

            When it becomes less than half

D: Permeability can be less than 1/2 of initial permeability in 7 days

     If not

(3) Evaluation of crack width

After fixation of the cracks, the concrete cured body was immersed in a polypropylene container with 20 liters of tap water, respectively, and curing was carried out in a 20 ° C constant temperature room. Then, the crack formation part of the hardened concrete body was observed using the digital microscope at the interval of 1 day, and the crack self-healing performance was evaluated.

Evaluation of Crack Width

A: Crack width decreased by 0.1 mm or more in 28 days

B: The crack width decreases more than 0.05 mm in 28 days.

     If less than 0.1 mm

C: The crack width decreases by more than 0.025 mm in 28 days.

     Less than 0.5mm

D: When the reduction in crack width in 28 days is less than 0.025 mm

[Table 3]

From Table 3, in Examples 18 to 22 of the present invention, in the case of Comparative Example 10 other than the present invention, the slump lowering of concrete was low, the exponential improvement and the crack width were decreased, and the crack self-healing performance was excellent. Although self-healing performance was excellent, the fall of slump was remarkable. In the case of the comparative example 11, since it was plain concrete which does not contain the self-healing material, although the slump was large, the self-healing performance was not confirmed at all.

The cement composition, mortar, and concrete containing the cement admixture of the present invention can be extremely suitably applied to a structure in which leaks such as underground structures, tunnels, etc. are liable to occur, and crack repair and repair are difficult. .

Claims (10)

A cement admixture, characterized in that it is a granulated product which is added by kneading cement and water as a binder material for granulation treatment to a crack self-healing material and contains a crack self-healing material as a main component. The method of claim 1,
Crack self-healing materials include layered silicate minerals, crystalline and amorphous silicate minerals, calcium phosphates, compounds and minerals with carbonate groups, compounds and minerals containing lithium, compounds and minerals containing magnesium, compounds containing fluorine, Pozzo is selected from at least one selected from the group consisting of reactive materials, materials having latent hydraulic properties, materials containing inflating materials or non-plastic materials, materials containing calcium oxide, and cement, and mixing in any mixing ratio. A cement admixture characterized by the above. The method according to claim 1 or 2,
The particle size of a granulated material exists in the range of 0.1-15 mm, The cement admixture. 4. The method according to any one of claims 1 to 3,
A cement admixture, characterized in that the order material is further included in the granulated material. The method of claim 4, wherein
The order material is a siliceous compound and / or an organic compound of fatty acid having 12 or more carbon atoms. The method according to any one of claims 1 to 5,
Cement admixture, characterized in that it further comprises a fiber and / or a water reducing agent. In the cement admixture according to any one of claims 1 to 6,
Cement as a binder material for the granulation treatment is kneaded by adding 5 to 200% by weight of the self-healing material and 10 to 100% by weight of the self-healing material, and the granulation processing of the obtained kneading material is performed at least once. Method for producing a cement admixture, characterized in that to produce a granulated product. The method of claim 7, wherein
A method for producing a cement admixture, wherein the granulated material after granulation is subjected to at least one order treatment. A cement composition comprising the cement admixture according to any one of claims 1 to 8 and cement. The mortar or concrete containing the cement admixture as described in any one of Claims 1-9, and cement, water, and aggregate.