Grout material, grout mortar composition, and hardened body

Abstract

To provide a grout material that has high flowability, allows improved self-curing effect, and also allows improved strength and wear resistance, a grout mortar composition and a cured body.SOLUTION: A grout material contains a grout admixture containing at least one non-hydraulic compound selected from the group consisting of γ-2CaO SiO2, 3CaO 2SiO2, α-CaO SiO2 and calcium magnesium silicate, and cement, gas foaming substance, water-reducing agent, and fine aggregate.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a grout material, a grout mortar composition, and a cured body formed using the grout mortar composition, which are used in the civil engineering and construction industries.

Background Art

[0002] Grout materials are used to improve the workability and filling properties of mortar and concrete and to perform grouting work smoothly. The main applications include the construction of underground structures, the installation of bridge supports, the installation of various machines, and the filling of gaps between walls and columns in seismic reinforcement. In order to fill the gaps between structures and integrate them, (1) the required fluidity according to the filling location and filling method, etc., (2) non-shrinkage that does not cause bleeding, settlement, and voids after filling, and (3) various required strengths according to the usage conditions of the structure are required (for example, see Non-Patent Document 1).

[0003] Since the volume of cement hardened bodies decreases with the hydration or drying of cement, there is a risk of cracking or a decrease in the adhesion performance with existing structures. The occurrence of cracks not only impairs the aesthetics but also poses a risk of adversely affecting the stability, waterproofness, and watertightness of the structure. Therefore, as an expansion material used for compensating for the shrinkage of cement, suppressing the occurrence of cracks, and maintaining the adhesion performance with the structure, for example, 3CaO·3Al2O3·CaSO4 (awin), calcium sulfoaluminate-based (awin-based expansion material) mainly composed of CaSO4 and CaO, lime-based (lime-based expansion material) mainly composed of free lime, and expansion materials containing free lime - hydraulic substances - gypsum, etc. are available.

[0004] In addition to cement and expansion materials, by combining specific water reducers, grout materials with low temperature dependence, significantly high fluidity and filling property retention effects, and long-term strength enhancement effects have been proposed (for example, see Patent Document 1). Furthermore, a high-strength grout material has been proposed that retains excellent fluidity, suppresses foam generation, has an optimal length change rate, and volume expansion rate (see, for example, Patent Document 2).

[0005] However, conventional grout materials have problems such as low fluidity, cracks occurring in the hardened body, low self-healing effect even after cracks occur, and low long-term strength and wear resistance.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Non-Patent Documents

[0007]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0008] Therefore, an object of the present invention is to provide a grout material, a grout mortar composition, and a hardened body that have high fluidity, can enhance the self-healing effect, become dense by natural carbonation, and have improved strength and wear resistance.

Means for Solving the Problems

[0009] The present invention has been made to solve the above problems. As a result of various efforts made by the present inventors to solve the above problems, it has been found that by containing a grout admixture containing a specific non-hydraulic material, the strength and wear resistance can be further enhanced and the durability can be improved, and the present invention has been completed. The gist of the present invention is as follows. [1]A grout material containing a cementitious admixture containing one or more non-hydraulic compounds selected from the group consisting of γ-2CaO·SiO2, 3CaO·2SiO2, α-CaO·SiO2, and calcium magnesium silicate, cement, a gas foaming agent, a water reducing agent, and fine aggregate. [2]The grout material according to [1], wherein Li is contained in the non-hydraulic compound, and the content rate of Li in the non-hydraulic compound is 0.001 to 1.0% by mass in terms of oxide conversion. [3]The grout material according to [1] or [2], wherein the amount of SO3 is 0.5% by mass or more and 10.0% by mass or less, and the amount of MgO is 0.1% by mass or more and 3.0% by mass or less. [4]As chemical components, in 100 parts by mass of the cementitious admixture for grout, it contains 0.001 to 1.0 part by mass of Li2O, 45 to 70 parts by mass of CaO, 29 to 55 parts by mass of SiO2, and 0 to 10 parts by mass of Al2O3, the grout material according to any one of [1] to [3]. [5]The grout material according to any one of [1] to [4], further containing an expanding agent. [6]Further containing a quick-setting material, the quick-setting material contains calcium aluminate, the calcium aluminate has a CaO / Al2O3 molar ratio of 1.0 or more and 3.0 or less, and the content ratio of the calcium aluminate is 2 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the cement, the grout material according to any one of [1] to [5]. [7]The content ratio of the fine aggregate is 40 parts by mass or more and 300 parts by mass or less with respect to 100 parts by mass of the cement, the grout material according to any one of [1] to [6]. [8]A grout mortar composition containing the grout material according to any one of [1] to [7] and water. [9]A cured body obtained by using the grout mortar composition according to [8].

Advantages of the Invention

[0010] According to the present invention, it is possible to provide a grout material, a grout mortar composition, and a cured body that have high fluidity, can further enhance the self-healing effect, become dense by natural carbonation, and have improved strength and wear resistance.

Embodiments for Carrying Out the Invention

[0011] Hereinafter, the present invention will be described in detail. In addition, parts and mass% in this specification are based on mass unless otherwise specified. Further, the grout mortar as used in this specification generally refers to a paste without coarse aggregate and a mortar containing fine aggregate.

[0012] The grout material of the present invention is a grout admixture containing one or more non-hydraulic compounds selected from the group consisting of γ-2CaO·SiO2, 3CaO·2SiO2, α-CaO·SiO2, and calcium magnesium silicate, and a grout material composed of cement, a gas foaming substance, a water reducing agent, and fine aggregate. In addition, the grout admixture further contains Li in the non-hydraulic compound, and the content rate of Li in the non-hydraulic compound is preferably 0.001 to 1.0% in terms of oxide conversion. Further, the content rate of Li in the non-hydraulic compound is preferably 0.005 to 1.0% in terms of oxide conversion, more preferably 0.010 to 0.90%, and still more preferably 0.015 to 0.80%. It is presumed that this predetermined amount of Li promotes the formation of vaterite, which is a kind of calcium carbonate, among the carbonations of C-S-H (calcium silicate hydrate), and it is considered that a denser cured state can be obtained by carbonation (salting), resulting in enhanced strength, improved wear resistance, and easy low shrinkage. Here, "containing Li in a non-hydraulic compound" means that the non-hydraulic compound contains Li₂O as a chemical composition (the presence can be confirmed by ICP emission spectrometry), but Li₂O is not identified by X-ray diffraction measurement (no distinct peak of Li₂O is observed), which does not simply refer to a state where the non-hydraulic compound and the Li compound are physically mixed. Such a state can be obtained by mixing the respective raw materials and performing heat treatment at a high temperature of 1,000 °C or higher. Hereinafter, each component and the like will be described.

[0013] (γ-2CaO·SiO₂) γ-2CaO·SiO₂ is a compound represented by 2CaO·SiO₂ and is known as a low-temperature phase, which is completely different from the high-temperature phases such as α-2CaO·SiO₂, α'-2CaO·SiO₂, and β-2CaO·SiO₂. Although all of them are represented by 2CaO·SiO₂, their crystal structures and densities are different.

[0014] (3CaO·2SiO₂) 3CaO·2SiO₂ is a mineral called rankinite, which contains CaO in pseudo-wollastonite. It is a mineral that is chemically stable without hydration activity, but has a large effect of promoting carbonation (salt).

[0015] (α-CaO·SiO₂) α-CaO·SiO₂ (α-type wollastonite) is a compound represented by CaO·SiO₂ and is known as a high-temperature phase, which is completely different from the low-temperature phase β-CaO·SiO₂. Although all of them are represented by CaO·SiO₂, their crystal structures and densities are different.

[0016] Naturally occurring wollastonite is the low-temperature phase β-CaO·SiO₂. β-CaO·SiO₂ has acicular crystals and has been used as an inorganic fibrous substance such as wollastonite fiber, but it does not have the effect of promoting carbonation (salt) like α-CaO·SiO₂ according to this embodiment.

[0017] (Calcium magnesium silicate) Calcium magnesium silicate is a general term for CaO-MgO-SiO2 based compounds. In this embodiment, it is preferably Merwinite represented by 3CaO·MgO·2SiO2 (C3MS2). According to Merwinite, a large carbonation promotion effect can be achieved.

[0018] The non-hydraulic compound as described above may be one kind or two or more kinds. However, the Li content in the non-hydraulic compound is 0.001 to 1.0% in terms of oxide conversion, preferably 0.005 to 1.0%, more preferably 0.010 to 0.90%, and still more preferably 0.015 to 0.80%. When the Li content is 0.001% or more in terms of oxide conversion, the carbonation promotion effect is easily obtained. Also, when the Li content is 1.0% or less in terms of oxide conversion, the cost can be reduced. The Li content in terms of oxide conversion can be measured by the method described in the examples. When there are two or more non-hydraulic compounds, the Li content refers to the content of the Li in terms of oxide conversion with respect to the total of the two or more non-hydraulic compounds.

[0019] Among the above non-hydraulic compounds, particularly γ-2CaO·SiO2 is preferable because it is accompanied by a pulverization phenomenon called dusting during production, so it requires less energy for pulverization compared to other compounds, has a large carbonation promotion effect over a long period of time, and on the other hand, has a very large neutralization suppression effect when combined with blast furnace cement at a low water binder ratio.

[0020] The non-hydraulic compound according to this embodiment is obtained by blending a CaO raw material, a SiO2 raw material, a MgO raw material, and a Li raw material in a predetermined molar ratio and then performing heat treatment. Examples of the CaO raw material include calcium carbonate such as limestone, calcium hydroxide such as slaked lime, by-product slaked lime such as acetylene by-product slaked lime, and fine powder generated from waste concrete blocks. Examples of the SiO2 raw material include silica stone, clay, and various siliceous dusts generated as industrial by-products typified by silica fume and fly ash. Examples of the MgO raw material include magnesium hydroxide, basic calcium carbonate, and dolomite. Examples of the Li raw material include lithium carbonate. When Li is contained in the CaO raw material, the SiO2 raw material, or the MgO raw material, it is not necessary to newly add the Li raw material. From the perspective of reducing non-energy-derived CO2 emissions during heat treatment, one or more types selected from industrial by-products containing CaO, such as by-product slaked lime, fine powder generated from waste concrete blocks, municipal solid waste incineration ash, and sewage sludge incineration ash, can be used. Among them, it is more preferable to use by-product slaked lime, which has a smaller amount of impurities compared to other industrial by-products.

[0021] As the by - produced slaked lime, there are by - produced slaked lime (depending on the method of producing acetylene gas by the calcium carbide method, there are wet products and dry products) by - produced in the process of producing acetylene gas by the calcium carbide method, and by - produced slaked lime contained in the dust captured in the wet dust collection process of the calcium carbide electric furnace, such as acetylene by - produced slaked lime. The by - produced slaked lime contains, for example, 65 - 95% (preferably 70 - 90%) of calcium hydroxide, and in addition, 1 - 10% of calcium carbonate and 0.1 - 6.0% (preferably 0.1 - 3.0%) of iron oxide. These ratios can be confirmed by the mass loss determined by fluorescent X - ray measurement and differential thermal gravimetric analysis (TG - DTA) (Ca(OH)2: around 405°C - 515°C, CaCO3: around 650°C - 765°C). The volume - average particle diameter measured by the laser diffraction / scattering method is about 50 - 100μm. Further, in JIS K 0068 "Method for Measuring Moisture in Chemical Products", the moisture content measured by the drying loss method is preferably 10% or less. Also, it may contain sulfur compounds such as CaS, A12S3, and CaC2·CaS, but preferably 2% or less.

[0022] The heat treatment at a high temperature of 1,000°C or higher described above is not particularly limited, but can be carried out, for example, by a rotary kiln or an electric furnace. The heat treatment temperature is not uniquely determined, but is usually carried out in the range of about 1,000 - 1,800°C, and often in the range of about 1,200 - 1,600°C.

[0023] This embodiment can also use industrial by - products containing the non - hydraulic compound described above. In this case, impurities coexist. Examples of such industrial by - products include steelmaking slag.

[0024] The CaO raw material and the SiO2 raw material may contain impurities, but there is no particular problem as long as the effects of the present invention are not inhibited. Specific examples of the impurities include, for example, Al2O3, Fe2O3, TiO2, MnO, Na2O, K2O, S, P2O5, F, B2O3, chlorine, and the like. Further, examples of the coexisting compounds include free calcium oxide, calcium hydroxide, calcium aluminate, calcium aluminosilicate, calcium ferrite, calcium aluminoferrite, calcium phosphate, calcium borate, magnesium silicate, leucite (K2O, Na2O)·Al2O3·SiO2, spinel MgO·Al2O3, magnetite Fe3O4, sulfur compounds such as the aforementioned CaS, A12S3, and CaC2·CaS.

[0025] Among these impurities, the content of S (sulfur) in the non-hydraulic compound is preferably 1.0% or less, more preferably 0.7% or less, and still more preferably 0.5% or less in terms of oxide (SO3) conversion. By being 1.0% or less, a sufficient carbonation promotion effect can be obtained, and the setting and hardening properties can be made within an appropriate range. The content of S in terms of oxide (SO3) conversion can be measured by fluorescent X-ray measurement. In addition, S (sulfur) in the non-hydraulic compound may be present as long as it is about 2% in terms of oxide conversion.

[0026] In the admixture for grout, the content of the non-hydraulic compound (the content in the total amount when multiple types are included) is preferably 65% or more, more preferably 70% or more, and still more preferably 75% or more. In addition, it is possible that hydraulic 2CaO·SiO2 other than γ-2CaO·SiO2 is mixed, and the maximum mixing amount can be up to 35%.

[0027] The content of γ-2CaO·SiO2 in the admixture for grout is preferably 35% or more, more preferably 45% or more. Further, the upper limit value of the content of γ-2CaO·SiO2 is not particularly limited. Among steelmaking slags, electric furnace reduction period slag or stainless steel slag having a high content of γ-2CaO·SiO2 is preferable.

[0028] Also, from the viewpoint of more easily exhibiting the effects in the admixture for grout, in terms of chemical components, it is preferable that in 100 parts by mass of the admixture for grout, 0.001 to 1.0 part by mass of Li2O, 45 to 70 parts by mass of CaO, 29 to 55 parts by mass of SiO2, and 0 to 10 parts by mass of Al2O3 are contained. The content of Li2O can be measured by the method described in the examples below. Also, CaO, SiO2, and Al2O3 can be measured by fluorescent X-ray. In terms of chemical components, it is more preferable that in 100 parts by mass of the admixture for grout, 0.002 to 0.5 part by mass of Li2O, 60 to 70 parts by mass of CaO, 29 to 45 parts by mass of SiO2, and 0.5 to 5 parts by mass of Al2O3 are contained. Furthermore, in terms of chemical components, it is preferable that the total of Li2O, CaO, SiO2, and Al2O3 in 100 parts by mass of the admixture for grout is 90 parts by mass or more, and more preferably 95 to 100 parts by mass.

[0029] As a method for quantifying the non-hydraulic compounds in the admixture for grout, the Rietveld method by powder X-ray diffraction method etc. can be mentioned.

[0030] The Blaine specific surface area of the admixture for grout is not particularly limited, but 1,500 cm 2 / g or more is preferable, and the upper limit is preferably 8,000 cm 2 / g or less. Among them, 2,000 to 6,000 cm 2 / g is more preferable, and 4,000 to 6,000 cm 2 / g is most preferable. When the Blaine specific surface area is 2,000 cm 2 / g or more, good material separation resistance can be obtained, and the carbonation promotion effect becomes sufficient. Also, when it is 8,000 cm 2 / g or less, the grinding power during grinding does not increase and it is economical, and also weathering is suppressed and deterioration of quality over time can be suppressed.

[0031] The amount of SO3 contained in the grout material in the present invention is preferably 0.5% by mass or more, more preferably 0.7% by mass or more, and even more preferably 0.8% by mass or more from the viewpoint of enhancing fluidity and improving the self-healing effect. Also, from the same viewpoint, the amount of SO3 contained in the grout material is required to be 10.0% by mass or less, preferably 8.0% by mass or less, and even more preferably 6.0% by mass or less. The amount of MgO contained in the grout material is preferably 0.1% by mass or more, more preferably 0.15% by mass or more, and even more preferably 0.2% by mass or more from the viewpoint of enhancing fluidity and improving the self-healing effect. Also, from the same viewpoint, the amount of MgO contained in the grout material is preferably 3.0% by mass or less, more preferably 2.0% by mass or less, and even more preferably 1.0% by mass or less.

[0032] The amounts of SO3 and MgO contained in the grout material can be adjusted, for example, by adding a mixing agent containing SO3 and MgO when preparing the grout material. Also, the amounts of SO3 and MgO can be measured by the fluorescent X-ray diffraction method (XRF).

[0033] The cement used in the present invention is not particularly limited, and examples include various cements such as ordinary, early-strength, ultra-early-strength, low-heat, and medium-heat cements, various blended cements obtained by mixing blast furnace slag, fly ash, silica fume, etc. with these cements, environment-friendly cements (eco-cements) manufactured using municipal waste incineration ash or sewage sludge incineration ash as raw materials, commercially available fine particle cements, etc. It is also possible to use various cements and various blended cements after being pulverized into fine powder. Also, those adjusted by increasing or decreasing the amounts of components (such as gypsum) usually used in cement can also be used. In the present invention, it is preferable to select ordinary Portland cement or early-strength Portland cement from the viewpoints of high fluidity, improvement of self-healing effect, enhancement of strength, and improvement of abrasion resistance.

[0034] The cement used in the present invention preferably has a Blaine specific surface area value of 2,500 cm 2 / g or more and 7,000 cm 2 / g or less, more preferably 2,750 cm 2 / g or more and 6,000 cm 2 / g or less, and even more preferably 3,000 cm 2 / g or more and 4,500 cm 2 / g or less, from the viewpoints of manufacturing cost and strength development property. The Blaine specific surface area value is determined in accordance with JIS R 5201 (Physical test methods for cement).

[0035] The grout material of the present invention can contain an expansive material from the viewpoints of generating an expansive hydrate and suppressing bleeding. The expansive material used in the present invention is not particularly limited, and any material can be used as long as it generates an expansive hydrate and suppresses bleeding. Examples of the expansive material include, but are not particularly limited to, free lime, free magnesia, calcium ferrite, ettringite-based, lime-based, and ettringite-lime composite-based materials. From the viewpoint of long-term stability, those containing free lime are preferred. Examples of those containing free lime include free lime-gypsum-based, free lime-hydraulic compound-based, and free lime-hydraulic compound-gypsum-based materials. Expansive materials are commercially available from various companies. Representative examples include, for example, "Denka CSA#20", "Denka Power CSA" manufactured by Denka Co., Ltd., "Expans", "Hyper Expans", "N-EX", "Bristar" manufactured by Pacific Materials Co., Ltd., and pulverized products thereof.

[0036] The particle size of the expansive material used in the present invention is not particularly limited, but is preferably in the range of 2,000 cm 2 / g or more and 25,000 cm 2 / g or less in terms of the Blaine specific surface area value, more preferably 2,200 cm 2 / g or more and 15,000 cm 2Those in the range of 2,400 cm 2 / g or more and 10,000 cm 2 / g or less are more preferable. By the Blaine specific surface area value of the expansion material being not less than the above lower limit value, bleeding can be suppressed. Also, by the Blaine specific surface area value of the expansion material being not more than the above upper limit value, sufficient expansibility can be obtained.

[0037] The content ratio of the expansion material used in the present invention is preferably 0.5 parts by mass or more and 20 parts by mass or less, more preferably 1.0 parts by mass or more and 18 parts by mass or less, and even more preferably 2 parts by mass or more and 15 parts by mass or less with respect to 100 parts by mass of cement. By the content ratio of the expansion material being not less than the above lower limit value, it becomes easier to obtain a crack suppression effect. By the content ratio of the expansion material being not more than the above upper limit value, the strength development property becomes good. By the content ratio of the expansion material being within the above range, it becomes easy to obtain a grout material that satisfies the effects of the present invention, that is, a grout material with enhanced fluidity, improved self-healing effect, and low shrinkage.

[0038] From the viewpoint of promoting setting and enhancing strength in the short term, the grout material of the present invention can contain a rapid hardening material. As the accelerating hardening material used in the present invention, there is no particular limitation as long as it promotes coagulation and enhances strength in a short period. As the accelerating hardening material for promoting coagulation, calcium salts of organic acids typified by calcium formate and calcium nitrate, nitrates, sulfates, carbonates, thiocyanates, amines, maleic anhydride, silicates typified by water glass, aluminum sulfate, and aluminum salts typified by alum, calcium aluminate (calcium aluminate), aluminates, etc. are mentioned. Among these, aluminates are preferable from the viewpoint of strength development, and it is preferable to contain calcium aluminate (CA). Calcium aluminate is more preferable from the viewpoint that the strength development property becomes good when used in combination with gypsum. The amount of gypsum used is preferably 80 parts by mass or more and 250 parts by mass or less, more preferably 90 parts by mass or more and 220 parts by mass or less, and even more preferably 100 parts by mass or more and 200 parts by mass or less with respect to 100 parts by mass of calcium aluminate. When the content ratio of gypsum is at least the above lower limit value, it becomes easier to obtain early hardening property. Further, when the content ratio of gypsum is at most the above upper limit value, the strength development property and the self-healing effect become good. When the content ratio of gypsum is within the above range, it becomes easy to obtain a grout material that improves the self-healing effect that satisfies the effects of the present invention. Calcium aluminate is a general term for hydraulically active substances mainly composed of CaO and Al2O3 obtained by mixing calcium oxide raw materials and alumina raw materials, etc., and firing in a kiln, or melting and cooling in an electric furnace, and can be used whether it is crystalline or amorphous. It is a material with a short hardening time and high initial strength development. A typical example of calcium aluminate is alumina cement, and usually, commercially available products can be used. For example, alumina cement No. 1, alumina cement No. 2, etc. can be used. Among them, amorphous calcium aluminate rapidly cooled after melting is preferable because it hardens in a shorter time than alumina cement and has high initial strength development thereafter. Among calcium aluminates, the molar ratio of CaO to Al2O3 (CaO / Al2O3 molar ratio) is preferably 1.0 or more and 3.0 or less, more preferably 1.7 or more and 2.5 or less. When the molar ratio is within the above range, the curing time can be further shortened and the initial strength development property can be enhanced.

[0039] In the present invention, the impurities contained in calcium aluminate are preferably 15% by mass or less, more preferably 10% by mass or less from the viewpoint of initial strength development property. Here, the impurities refer to substances other than CaO and Al2O3. When the impurities exceed 15% by mass, it takes time for curing and there may be a case where it does not harden at low temperatures. Representative examples of the impurities include silicon oxide, magnesium oxide, and sulfur oxide. In addition, there are those in which organic substances, alkali metal oxides, alkaline earth metal oxides, titanium oxide, iron oxide, alkali metal halides, alkaline earth metal halides, alkali metal sulfates, and the alkaline earth metal sulfates are substituted or solid-solved in part of CaO and Al2O3. However, it is not limited thereto.

[0040] The vitrification rate of calcium aluminate used in the present invention is preferably 70% by mass or more, more preferably 90% by mass or more in terms of reaction activity. When the vitrification rate is less than 70% by mass, the initial strength development property may decrease. The vitrification rate of calcium aluminate is preferably 70% by mass or more, more preferably 90% by mass or more in terms of reaction activity. The vitrification rate is measured for the measurement sample by first measuring the main peak area S of the crystal mineral by powder X-ray diffraction method, then heating at 1,000 °C for 2 hours, gradually cooling at a cooling rate of (1 to 10 °C) / min, and obtaining the main peak area S0 of the crystal mineral after heating by powder X-ray diffraction method. Using these values of S0 and S, the vitrification rate X is calculated. Vitrification rate (% by mass) = 100 × (1 - S / S0) The particle size of calcium aluminate is preferably 3, {{000}} cm 2 / g or more in terms of initial strength development property, 5, {{000}} cm 2More preferably, it is 〇〇 / g or more. When the particle size of calcium aluminate is at least the above lower limit value, the hardening time is shortened, so that the initial strength development property is good and the self-healing performance is good.

[0041] The content ratio of the quick-setting material used in the present invention is preferably 1 part by mass or more and 30 parts by mass or less, more preferably 3 parts by mass or more and 25 parts by mass or less, and still more preferably 5 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of cement. When containing calcium aluminate as the quick-setting material, the content ratio of calcium aluminate is preferably 2 parts by mass or more and 20 parts by mass or less, more preferably 3 parts by mass or more and 18 parts by mass or less, and still more preferably 4 parts by mass or more and 15 parts by mass or less with respect to 100 parts by mass of cement. When the content ratios of the quick-setting material and calcium aluminate are at least the above lower limit values, it becomes easy to obtain early hardening property and crack suppression effect. Further, when the content ratios of the quick-setting material and calcium aluminate are at most the above upper limit values, the strength development property is good. When the content ratio of the quick-setting material is within the above range, it becomes easy to improve the self-healing effect, and a grout material satisfying the effects of the present invention can be obtained. The content rate of calcium aluminate in the quick-setting material is preferably 20 to 100%, more preferably 25 to 80%, and still more preferably 30 to 60%.

[0042] The gas foaming substance used in the present invention refers to a substance used for the purpose of suppressing the settlement and shrinkage due to bleeding of the grout material in a state where it has not yet solidified after the grout mortar composition is constructed. The gas foaming substance used in the present invention may be any substance that generates gas after kneading with water, and is not particularly limited.

[0043] Examples of the gas foaming substance include oily substances such as vegetable oil and mineral oil. Further, examples of the gas foaming substance include powdery substances such as flaky aluminum powder surface-treated with stearic acid and aluminum powder produced by an atomizing method. Further, examples of the gas foaming substance include nitrogen gas foaming substances that generate nitrogen gas in an alkaline atmosphere, such as azo compounds, nitroso compounds, and hydrazine derivatives. Further, examples of the gas foaming substance include percarbonates such as sodium percarbonate, potassium percarbonate, and ammonium percarbonate, perborates such as sodium perborate and potassium perborate, permanganates such as sodium permanganate and potassium permanganate, and peroxide substances such as hydrogen peroxide. As the gas foaming substance used in the present invention, it is preferable to use aluminum powder surface-treated with stearic acid or the like because of its great sedimentation suppression effect.

[0044] The nitrogen gas foaming substance used as the gas foaming substance in the present invention contains a compound that generates nitrogen gas by reaction with an alkali generated when the cement contained in the grout material is kneaded with water, and may by-produce gases such as carbon monoxide, carbon dioxide, and ammonia. The nitrogen gas foaming substance used in the present invention is not particularly limited as long as it can be used for integrating with a structure, suppressing the settlement and shrinkage of the still-unset grout mortar, and further improving the crack resistance when placed in a dry state.

[0045] The content ratio of the gas foaming substance is preferably 0.0001 part by mass or more and 1 part by mass or less, more preferably 0.0005 part by mass or more and 0.5 part by mass or less, and even more preferably 0.001 part by mass or more and 0.2 part by mass or less with respect to 100 parts by mass of cement. By the content ratio of the gas foaming substance being at least the above lower limit value, a sufficient initial expansion effect can be imparted. Further, by the content ratio of the gas foaming substance being at most the above upper limit value, the strength development property becomes good.

[0046] The water-reducing agent used in the present invention helps to disperse each material and plays a role in imparting fluidity to the kneaded grout mortar.

[0047] The water-reducing agent used in the present invention is not particularly limited. For example, naphthalene-based water-reducing agents, melamine-based water-reducing agents, amino sulfonic acid-based water-reducing agents, and polycarboxylic acid-based water-reducing agents can be mentioned. In the present invention, one or more of these water-reducing agents can be used. Specific examples of the water-reducing agent include, for example, as naphthalene-based water-reducing agents, products named "Reobuild SP-9 series" manufactured by NMB Co., Ltd., products named "Mighty 2000 series" manufactured by Kao Corporation, and products named "Sunflow HS-100" manufactured by Nippon Paper Industries Co., Ltd. etc. can be mentioned. As melamine-based water-reducing agents, products named "Seekament 1000 series" manufactured by Nippon Shika Co., Ltd. and products named "Sunflow HS-40" manufactured by Nippon Paper Industries Co., Ltd. etc. can be mentioned. As amino sulfonic acid-based water-reducing agents, products named "Paric FP-200 series" manufactured by Fujisawa Pharmaceutical Co., Ltd. etc. can be mentioned. As polycarboxylic acid-based water-reducing agents, products named "Reobuild SP-8 series" manufactured by NMB Co., Ltd., products named "Darlex Super 100PHX" manufactured by Grace Chemicals, and products named "Chupol HP-8 series", "Chupol HP-11 series" etc. manufactured by Takemoto Yushi Co., Ltd. can be mentioned. There are also powdered water-reducing agents. Specifically, as naphthalene-based water-reducing agents, products named "Mighty 100" manufactured by Kao Corporation, products named "Sanyo Leviron P" manufactured by Sanyo Chemical Industries Co., Ltd., and products named "Selflow 110P" manufactured by Daiichi Kogyo Seiyaku Co., Ltd. etc. can be mentioned. As melamine-based water-reducing agents, "Mermet F10M" manufactured by BASF Pozolith Co., Ltd. etc. can be mentioned. As polycarboxylic acid-based water-reducing agents, for example, products named "Quinflow 750" manufactured by Mitsubishi Chemical Corporation and products named "CAD9000P" manufactured by Kao Corporation etc. can be mentioned.

[0048] The content ratio of the water reducing agent is preferably 0.1 part by mass or more and 2 parts by mass or less in terms of solid content based on 100 parts by mass of cement, more preferably 0.2 part by mass or more and 1.8 parts by mass or less, and even more preferably 0.3 part by mass or more and 1.0 part by mass or less. By the content ratio of the water reducing agent being not less than the above lower limit value, sufficient fluidity can be obtained. Also, by the content ratio of the water reducing agent being not more than the above upper limit value, segregation of materials can be suppressed.

[0049] The chemical composition of the fine aggregate used in the present invention preferably has a CaO ratio of 85% by mass or more and an SiO2 ratio of 0.2% by mass or more and 15% by mass or less. By the CaO ratio and the SiO2 ratio of the chemical composition of the fine aggregate being within the above ranges, a grout material excellent in high fluidity, carbonation resistance, adhesion strength to reinforcing bars, and rust prevention can be obtained. The CaO ratio is preferably 87% by mass or more, more preferably 89% by mass or more, and even more preferably 91% by mass or more. The upper limit of the CaO ratio is not particularly limited, but is preferably 99% by mass or less, and more preferably 98.5% by mass or less. The SiO2 ratio is preferably 0.25% by mass or more and 13% by mass or less, more preferably 0.3% by mass or more and 11% by mass or less, and even more preferably 0.4% by mass or more and 10% by mass or less. In order to make the chemical composition of the fine aggregate within the above ranges and the ranges described below, silica sand, calcite, scapolite which is a metamorphic rock, quartz which is an igneous rock, potassium feldspar, etc. are mixed and prepared. The chemical composition is adjusted by mixing each rock while confirming with fluorescent X-ray diffraction so as to fall within the scope of the present invention. Note that the chemical composition of the fine aggregate used in the present invention is calculated in terms of oxides.

[0050] As the fine aggregate used in the present invention, the same fine aggregates as those used in ordinary cement mortar and concrete can be used. That is, river sand, crushed stone, crushed sand, lime sand, silica sand, colored sand, artificial lightweight aggregate, etc. can be used, and it is also possible to combine these. In particular, for applications aimed at enhancing fluidity and self-healing effect, the use of siliceous silica sand or lime sand is preferred, and the particle size of the fine aggregate is preferably JIS No. 6 to 8.

[0051] The content ratio of the fine aggregate is preferably 40 parts by mass or more and 300 parts by mass or less, more preferably 45 parts by mass or more and 275 parts by mass or less, and even more preferably 50 parts by mass or more and 250 parts by mass or less with respect to 100 parts by mass of cement. When the particle size of the fine aggregate is within the above range, sufficient fluidity, self-healing effect, improvement in abrasion resistance, and low shrinkage can be obtained.

[0052] In addition to cement, an expansion agent, a gas foaming substance, a water reducing agent, and a fine aggregate, the grout material of the present invention can contain siliceous fine powder from the viewpoint of improving strength development, improving acid resistance, ensuring pot life, and improving dimensional stability.

[0053] Examples of the siliceous fine powder include latent hydraulic substances such as blast furnace slag fine powder, pozzolanic substances such as fly ash and silica fume. Among them, silica fume is preferred. The type of silica fume is not limited, but from the viewpoint of fluidity, the use of silica fume containing 10% or less of ZrO2 as an impurity or acidic silica fume is more preferred. Acidic silica fume refers to a substance that shows acidity with a pH of 5.0 or less of the supernatant when 1 g of silica fume is put into 100 cc of pure water and stirred.

[0054] The powder fineness of the siliceous fine powder is not particularly limited, but usually, blast furnace slag fine powder and fly ash have a Blaine value in the range of 3,000 cm 2 / g or more and 9,000 cm 2 / g or less, and silica fume has a BET specific surface area of 20,000 cm 2300,000 cm or more per g 2 is in the range of 300,000 cm or less per g.

[0055] The content ratio of the silica fine powder is preferably 1 part by mass or more and 20 parts by mass or less, more preferably 2 parts by mass or more and 15 parts by mass or less, and still more preferably 3 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the cement. By the content ratio of the silica fine powder being at least the above lower limit value, improvement in strength development property, improvement in acid resistance, ensuring of workable time, and good dimensional stability can be achieved. Further, by the content ratio of the silica fine powder being at most the above upper limit value, fluidity can be improved and the self-healing effect can be improved.

[0056] In the present invention, within a range not adversely affecting the performance, a setting regulator, an AE agent, a rust preventive agent, a water repellent agent, an antibacterial agent, a coloring agent, an antifreeze agent, limestone fine powder, blast furnace granulated slag fine powder, sewage sludge incineration ash and its molten slag, municipal waste incineration ash and its molten slag, and pulp sludge incineration ash, etc., admixture materials, an antifoaming agent, a thickening agent, a shrinkage reducing agent, steel fiber, vinylon fiber, carbon fiber, and wollastonite fiber, etc., fiber substances, polymers, clay minerals such as bentonite and sepiolite, and anion exchangers such as hydrotalcite, etc., one or more of them can be used within a range not substantially inhibiting the object of the present invention.

[0057] In the grout material of the present invention, the mixing method of each material is not particularly limited, and each material may be mixed during construction, or a part or all of them may be mixed in advance. As the mixing device, any existing device, for example, a tilting drum mixer, an omnimixer, a Henschel mixer, a V-type mixer, and a Nauta mixer, etc., can be used.

[0058] The grout mortar composition of the present invention contains the above-described grout material of the present invention and water, and is obtained by kneading the grout material and water. The amount of water for kneading in the present invention is not particularly limited because it varies depending on the purpose of use and the content ratio of each material. However, it is preferably 10 parts by mass or more and 70 parts by mass or less, more preferably 14 parts by mass or more and 65 parts by mass or less, and even more preferably 16 parts by mass or more and 60 parts by mass or less with respect to 100 parts by mass of the grout material. When the amount of water for kneading is equal to or more than the above lower limit value, it is possible to suppress a decrease in fluidity and suppress an extremely large calorific value. Further, when the amount of water for kneading is equal to or less than the above upper limit value, it is possible to ensure strength development property.

[0059] In the present invention, the method of kneading the grout material and water is not particularly limited, but it is preferable to use a hand mixer with a rotation speed of 900 rpm or more, a normal high-speed grout mixer, or a twin-shaft forced mixer.

[0060] For kneading with a hand mixer or a high-speed grout mixer, for example, it is preferable to put a predetermined amount of water in a container such as a pail or a mixer in advance, and then add the grout mortar composition while rotating the mixer and knead for 3 minutes or more. Also, for kneading with a forced mixer, for example, it is preferable to put the grout mortar composition into the mixer in advance, add a predetermined amount of water while rotating the mixer, and knead for at least 4 minutes or more. If the kneading time is less than the predetermined time, appropriate fluidity of the grout mortar may not be obtained due to insufficient kneading. The kneaded grout mortar is usually pumped to the construction site by a manual injection gun, a diaphragm hand pump, or a mortar pump such as a squeeze type and filled to form a cured body using the grout mortar composition of the present invention.

Examples

[0061] Hereinafter, the present invention will be further described based on experimental examples of the present invention, but the present invention is not limited thereto.

[0062] [Experimental Example 1] Based on 100 parts by mass of cement, it contains 166.7 parts by mass of fine aggregate, 11.7 parts by mass of expansive agent, 0.0025 parts by mass of gas foaming substance, and 0.5 parts by mass of water reducing agent. The grout admixture was prepared to contain the parts by mass shown in Table 1 based on 100 parts by mass of cement, and a grout material was obtained. Based on 100 parts by mass of the obtained grout material, it was kneaded with 23 parts by mass of water to prepare a grout mortar composition. The fluidity, self-healing effect, compressive strength, and abrasion resistance test of the prepared grout mortar composition were measured. The results are also shown in Table 1.

[0063] <Materials Used> · Cement: Pilot-produced cement (various commercially available pure chemicals were used for the blending raw materials and adjustment of chemical components in the cement factory), Blaine value 3,450 cm 2 / g · Expansive agent: Prepared by blending CaO raw material, Al2O3 raw material, SiO2 raw material, and CaSO4 raw material, mixing and pulverizing, then firing at 1,200 °C to synthesize clinker, and pulverizing to a Blaine specific surface area of 3,000 cm 2 / g. · Gas foaming substance: Flaky aluminum powder surface-treated with stearic acid, commercially available product · Water reducing agent: Naphthalene-based water reducing agent, commercially available product (''Selflo-110P'' manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) · Water: Tap water · Fine aggregate: Lime sand, a mixture of 50% below 0.6 mm and 50% between 0.6 and 1.2 mm was used. · Grout admixture A: Li-containing γ-2CaO·SiO2. Reagent-grade calcium carbonate and reagent-grade silicon dioxide were mixed at a molar ratio of 2:1, and further reagent-grade lithium carbonate was mixed so that the Li content in the mixture was 0.0005 - 1.1% (internal substitution) in terms of oxide (Li2O), heat-treated at 1,400 °C for 2 hours, left to room temperature, and a grout admixture A with a Blaine specific surface area of 4,000 cm 2 / g was prepared. The Li content in terms of oxides in each cement admixture was measured by an ICP emission spectrometer (manufactured by Hitachi High-Technologies Corporation, VISTA-PRO). And from the absolute calibration curve method using the diluted SPEX XSTC-22 ICP mixture solution, it has been confirmed that the Li content is the same as the charged amount. The measurement conditions are as follows. · Li measurement wavelength: 670.783 nm · BG correction: Fitting curve method · Standard solution for calibration curve: Dilute the SPEX XSTC-22 ICP mixture solution and use it Calibration curve range: 0 - 5 mg / L (5-point calibration curve of 0 mg / L, 0.1 mg / L, 0.5 mg / L, 1 mg / L, 5 mg / L) · Quantitative determination by absolute calibration curve method · Grout admixture B: Li-containing α-CaO·SiO2. Reagent-grade calcium carbonate and reagent-grade silicon dioxide were mixed at a molar ratio of 1:1, and further reagent-grade lithium carbonate was mixed so that the Li content in the mixture was 0.0005 - 1.1% (internal substitution) in terms of oxide (Li2O). Heat treatment was carried out at 1,500 °C for 2 hours, left to cool to room temperature, and a grout admixture B with a Blaine specific surface area of 4,000 cm 2 / g was prepared. · Grout admixture C: β-2CaO·SiO2. Reagent-grade calcium carbonate and reagent-grade silicon dioxide were mixed at a molar ratio of 2:1, heat-treated at 1,400 °C for 2 hours, left to cool to room temperature, and pulverized. The same heat treatment was repeated until the peak of γ-2CaO·SiO2 was no longer confirmed by XRD. After only the peak of β-2CaO·SiO2 was confirmed, a grout admixture C with a Blaine specific surface area of 4,000 cm 2 / g was prepared.

[0064] <Measurement items> · Fluidity: In accordance with JSCE-F541, measured at the J 14 funnel flow value immediately after remixing (immediately after preparing the grout mortar composition) and after 30 minutes. ·Self-healing effect: In accordance with JISA6206, a grout mortar composition was placed in a shape of 10 cm × 10 cm × 40 cm under the condition of steel bar restraint. After 56 days of age, strain gauges were attached to the surface of the specimen and a bending test was conducted. When cracks with a crack width of 0.1 mm occurred, the bending test was terminated. Then, after standing for 28 days under the conditions of 98% by mass humidity and 35 °C, and repeating the standing for 7 days under the conditions of 60% by mass humidity and 20 °C for 5 cycles, the area ratio of the closed cracks (closed area / area where cracks occurred) was measured to confirm the self-healing effect. ·Compressive strength: In accordance with JSCE G505, the grout mortar composition was placed in a mold of φ5 × 10 cm. After demolding at 1 day of age, it was cured in water at 20 °C until 28 days of age. Thereafter, it was naturally carbonated under air-dry curing. The compressive strength was measured at 700 days of age. ·Abrasion resistance test: The grout mortar composition was placed in a donut-shaped mold with an outer diameter of φ100 × 10 mm and an inner diameter of φ6.35 mm. After demolding at 1 day of age, it was cured in water at 20 °C until 28 days of age. Thereafter, it was naturally carbonated under air-dry curing. At 700 days of age, it was subjected to a Taber abrasion test (weight loss method). The test conditions were a load of 1 kg, an abrasion wheel of H-22, and 1,000 test cycles.

[0065]

Table 1

[0066] From the results in Table 1, it was confirmed that by containing a grout admixture containing a specific non-hydraulic material, high fluidity and self-healing effect can be further enhanced, and strength and abrasion resistance are improved.

[0067] [Experimental Example 2] Based on 100 parts by mass of cement, 0.0025 parts by mass of a gas foaming substance and 0.5 parts by mass of a water reducing agent were contained, and a grout admixture, an expansion material, a rapid hardening material, and fine aggregate were prepared to contain the parts by mass shown in Table 2 based on 100 parts by mass of cement, thereby obtaining a grout material. Next, for the grout material, the SO3 content was measured by X-ray fluorescence diffraction, and the MgO content was measured by X-ray fluorescence diffraction. Then, considering the measured values, a SO3-containing admixture (material name: potassium sulfate) and an MgO-containing admixture (material name: magnesium carbonate) were mixed so that the SO3 content and the MgO content described in Table 2 below were obtained in the final grout material, thereby preparing a grout material. Based on 100 parts by mass of the obtained grout material, 23 parts by mass of water was kneaded to prepare a grout mortar composition. The fluidity, self-healing effect, compressive strength, and abrasion resistance test of the prepared grout mortar composition were measured. The results are also shown in Table 2.

[0068] <Materials Used> · Rapid hardening material A: Adjusted to have 43% CaO and 53% Al2O3, and an amorphous calcium aluminate (vitrification rate of 98% or more, Blaine specific surface area of 6,050 cm 2 / g, CaO / Al2O3 molar ratio of 1.48) melted and rapidly cooled in an electric furnace, and a mixture of 150 parts by mass of gypsum mixed with 100 parts by mass of this calcium aluminate was used. · Rapid hardening material B: CaO / Al2O3 molar ratio of 1.20, alumina cement No. 1, manufactured by Denka Co., Ltd. · Rapid hardening material C: Calcium formate, reagent · Rapid hardening material D: Calcium nitrate, reagent

[0069]

Table 2

Industrial Applicability

[0070] The grout material of the present invention contains specific non-hydraulic materials, thereby enabling higher fluidity and self-healing effect, and also improving strength and abrasion resistance. It can be widely used in various applications such as the steel plate erection method for bridge piers, the filling method for large bearings, the fixing material for reinforcing bars, other gap filling, concrete cross-section repair, self-leveling floor materials, etc., as well as civil engineering and construction applications.

Claims

1. γ-2CaO·SiO ２ , 3CaO·2SiO ２ , α-CaO·SiO ２ and contains one or more non-hydraulic compounds selected from the group consisting of calcium magnesium silicate, a grout admixture, cement, a gas foaming agent, a water reducing agent, and fine aggregate A grout material, wherein Li is contained in the non-hydraulic compound, and the content rate of Li in the non-hydraulic compound is 0.001 to 1.0% by mass in terms of oxide.

2. γ-2CaO·SiO ２ 、3CaO·2SiO ２ 、α-CaO·SiO ２ and contains one or more non-hydraulic compounds selected from the group consisting of calcium magnesium silicate, a grout admixture, cement, a gas foaming substance, a water reducing agent, and fine aggregate SO ３ A grout material in which the amount of SO is 0.5% by mass or more and 10.0% by mass or less, and the amount of MgO is 0.1% by mass or more and 3.0% by mass or less.

3. The grout material according to claim 1 or 2, further containing an expansive agent.

4. Further containing a quick-setting material, wherein the quick-setting material contains calcium aluminate, wherein the calcium aluminate has a CaO / Al ２ O ３ molar ratio of 1.0 or more and 3.0 or less, and the content ratio of the calcium aluminate is 2 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the cement. The grout material according to any one of claims 1 to 3.

5. The content ratio of the fine aggregate is 40 parts by mass or more and 300 parts by mass or less with respect to 100 parts by mass of the cement. The grout material according to any one of claims 1 to 4.

6. A grout mortar composition containing the grout material according to any one of claims 1 to 5 and water.

7. A cured body obtained by using the grout mortar composition according to claim 6.

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