Grout material, grout mortar composition and hardened product

Abstract

To provide a grout material, a grout mortar composition, and a cured body that reduce heat of hydration and drying shrinkage and enhance filling property without using too much water reducing agent.SOLUTION: A grout material contains cement, an expanding admixture, a gas foaming substance, a water-reducing admixture, fine aggregate A, and fine aggregate B. The fine aggregate A has a particle size of less than 1.2 mm and an average particle size of 0.4-0.8 mm. The fine aggregate B has a particle size in the range of 1.2-10 mm and an average particle size of 2-9 mm. A mass ratio (fine aggregate A / fine aggregate B) of the fine aggregate A to the fine aggregate B is 50-200% and an angle of repose is 40-55°.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a grout material, a grout mortar composition, and a hardened product obtained by using the grout mortar composition, which are mainly used in the civil engineering and construction industries. [Background technology]

[0002] Grout materials are used to improve the workability and filling properties of mortar and concrete, and to facilitate grouting work. Its main applications include the construction of underground structures, the installation of bridge bearings, the installation of various types of machinery, and the filling of gaps in walls and columns in earthquake-resistant reinforcement. In order to fill and integrate gaps in structures, it is required to have (1) the required fluidity depending on the filling location and filling method, (2) non-shrinkage properties that prevent bleeding, settlement, and the generation of voids after filling, and (3) various strengths required depending on the conditions of use of the structure (see, for example, non-patent document 1).

[0003] Hardened cement paste loses volume as the cement hydrates or dries, which can lead to cracks and a decrease in adhesion to existing structures. Cracks not only ruin the aesthetic appearance, but can also have a negative impact on the stability, waterproofing, and watertightness of the structure. Therefore, the expanding materials used to compensate for cement shrinkage, prevent cracking, and maintain adhesion to structures include, for example, 3CaO·3Al2O3·CaSO4 (auin), calcium sulfoaluminate-based materials (auin-based expanding materials) whose main components are 3CaO·3Al2O3·CaSO4 and CaO, lime-based materials whose main component is free lime (lime-based expanding materials), and expanding materials containing free lime, hydraulic substances, and gypsum.

[0004] Grout materials have been proposed that combine cement, expansive materials, and specific water-reducing agents to have low temperature dependency, significantly high fluidity and filling retention, and long-term strength-enhancing effects (see, for example, Patent Document 1). Furthermore, a high-strength grout material has been proposed that has excellent fluidity, suppresses bubble generation, and maintains an optimum length change rate and volume expansion rate (see, for example, Patent Document 2).

[0005] However, conventional grout materials containing expansive additives have the risk of losing their fluidity and expansion performance when stored beyond the quality assurance period due to moisture seeping in from the outside, especially at high temperatures. Furthermore, when applied to relatively large areas such as mass concrete, the high heat of hydration can cause drying shrinkage cracks, and excessive use of water-reducing agents to improve filling properties can lead to the risk of solid-liquid separation of the grout. Therefore, there is a need to reduce the heat of hydration and drying shrinkage, and to improve filling properties without using an excessive amount of water-reducing agent. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 3894780 [Patent Document 2] International Publication No. 2007 / 029399 Brochure [Non-patent literature]

[0007] [Non-Patent Document 1] New Admixtures for Cement and Concrete, pp. 304-307, Yoshio Kasai and Etsuro Sakai, Gijutsu Shoin, published January 15, 2007 Summary of the Invention [Problem to be solved by the invention]

[0008] An object of the present invention is to provide a grout material, a grout mortar composition, and a hardened product thereof that reduce heat of hydration and drying shrinkage and have improved filling properties without using an excessive amount of water-reducing agent. [Means for solving the problem]

[0009] The present invention has been made to solve the above-mentioned problems, and as a result of various efforts made by the inventors to solve the above-mentioned problems, they discovered that a grout material prepared by combining specific fine aggregates has low heat of hydration and drying shrinkage, and also improves filling properties, and they have thus completed the present invention. The gist of the present invention is as follows. [1] A grout material containing cement, an expansive agent, a gas foaming agent, a water reducing agent, fine aggregate A, and fine aggregate B, wherein the particle size of the fine aggregate A is less than 1.2 mm and the average particle size is 0.4 to 0.8 mm, the particle size of the fine aggregate B is in the range of 1.2 to 10 mm and the average particle size is 2 to 9 mm, the mass ratio of the fine aggregate A to the fine aggregate B (fine aggregate A / fine aggregate B) is 50 to 200%, and the angle of repose is 40 to 55°. [2] The grout material described in [1] above, wherein the expansive material contains ternesite, and the content of the ternesite is 0.05 parts by mass or more and 20 parts by mass or less per 100 parts by mass of the expansive material. [3] The grout material according to [1] or [2] above, wherein the fine aggregate A has a reduction in coarseness ratio of 70% or more and 100% or less according to JIS A1121 "Abrasion test of coarse aggregate using a Los Angeles testing machine." [4] The grout material according to any one of [1] to [3] above, wherein the chemical components of the fine aggregate A are such that the proportion of CaO is 85% by mass or more, the proportion of SiO2 is 0.2% by mass or more and 14% by mass or less, the proportion of K2O is 40 ppm by mass or more and 3,000 ppm by mass or less, and the proportion of SO3 is 40 ppm by mass or more and 3,000 ppm by mass or less, and the chemical components of the fine aggregate B are such that the proportion of SiO2 is 75% by mass or more. [5] The grout material according to any one of [1] to [4] above, wherein the chemical components of the fine aggregate A are such that the proportion of Fe2O3 is 0.1 mass% or more and 3.0 mass% or less, and the proportion of Al2O3 is 0.1 mass% or more and 3.0 mass% or less. [6] The grout material according to any one of [1] to [5] above, wherein the content of the fine aggregate A is 50 parts by mass or more and 300 parts by mass or less per 100 parts by mass of the cement, and the content of the fine aggregate B is 50 parts by mass or more and 300 parts by mass or less per 100 parts by mass of the cement. [7] A grout mortar composition containing the grout material according to any one of [1] to [6] above and water. [8] A hardened body obtained by using the grout mortar composition described in [7] above. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a grout material, a grout mortar composition, and a hardened product that reduce heat of hydration and drying shrinkage and improve filling properties without using an excessive amount of water-reducing agent. BEST MODE FOR CARRYING OUT THE INVENTION

[0011] The present invention will be described in detail below. In this specification, parts and percentages are by mass unless otherwise specified. In addition, the term "grout mortar" as used in this specification is a general term for paste containing no coarse aggregate and mortar containing fine aggregate.

[0012] The grout material of the present invention is a grout material containing cement, an expansive agent, a gas foaming substance, a water reducing agent, fine aggregate A, and fine aggregate B, wherein the particle size of the fine aggregate A is less than 1.2 mm and the average particle size is 0.4 to 0.8 mm, the particle size of the fine aggregate B is in the range of 1.2 to 10 mm and the average particle size is 2 to 9 mm, the mass ratio of the fine aggregate A to the fine aggregate B (fine aggregate A / fine aggregate B) is 50 to 200%, and the angle of repose is 40 to 55°. The inventors have focused on fine aggregate and discovered that the angle of repose and the ratio of two types of fine aggregate with specific particle sizes affect the packing properties of grout materials. The present invention was completed based on this finding. In other words, if the angle of repose of the grout material is less than 40° or more than 55°, or if the average particle diameter of fine aggregate A is less than 0.4 mm or more than 0.8 mm, or if the average particle diameter of fine aggregate B is less than 2 mm or more than 9 mm, or if the mass ratio of fine aggregate A to fine aggregate B (fine aggregate A / fine aggregate B) is less than 50% or more than 200%, the filling ability will be low.

[0013] <Angle of repose> The angle of repose of the grout material of the present invention is 40 to 55°. When the angle of repose is in this range, the filling property is improved. From the above viewpoints, the angle of repose is preferably 42 to 50°, more preferably 43 to 49°, and even more preferably 45 to 48°. The angle of repose of a grout material can be adjusted, for example, by changing the particle size and proportions of the cement, expansive additive, gas-forming agent, water-reducing agent, fine aggregate A, and fine aggregate B contained in the grout material. The particle size of the cement and fine aggregate, which are the main components of the grout material of the present invention, has a particularly large effect, with smaller particle sizes tending to result in a smaller angle of repose. For example, a grout material with an angle of repose of 40 to 55° can be obtained by incorporating 20 to 40% by mass of fine aggregate A, 20 to 60% by mass of fine aggregate B, and 10 to 40% by mass of cement with a particle size of 5 to 20 μm. Furthermore, the angle of repose of the grout material can be adjusted by using a finer cement depending on the materials used. Furthermore, when a large amount of expansive additive is added, the angle of repose can be adjusted by changing its particle size, thereby achieving the range within which the effects of the present invention are achieved. The angle of repose was obtained by allowing the measurement sample to fall naturally onto a table with a diameter of 80 mm using a funnel and measuring the angle of the resulting powder peak.

[0014] <Fine aggregate> The grout material of the present invention has two types of fine aggregates, one of which (fine aggregate A) has a particle diameter of less than 1.2 mm. When the particle diameter of fine aggregate A is within this range, the packing property is improved. From the above viewpoints, the particle diameter of fine aggregate A is preferably 1.1 mm or less, and more preferably 1.0 mm or less. Furthermore, the average particle diameter of fine aggregate A is 0.4 to 0.8 mm. When the average particle diameter of fine aggregate A is within this range, the packing property is improved. From the above viewpoints, the average particle diameter of fine aggregate A is preferably 0.5 to 0.8 mm, and more preferably 0.6 to 0.8 mm. The grout material of the present invention also contains another fine aggregate (fine aggregate B) with a particle size ranging from 1.2 to 10 mm, with an average particle size of 2 to 9 mm. When the particle size of fine aggregate B is within this range, a good balance with fine aggregate A is achieved, making it easier to obtain the suitable angle of repose. From the above viewpoints, the particle size of fine aggregate B is preferably within the range of 1.2 to 8 mm, and more preferably within the range of 1.2 to 6 mm. Furthermore, when the average particle size of fine aggregate B is within the above range, a good balance with fine aggregate A is achieved, the above-mentioned preferable angle of repose is obtained, and the effects of the present invention are achieved. From the above viewpoints, the average particle size is more preferably 3 to 7 mm, and even more preferably 4 to 5 mm. Furthermore, the mass ratio of the fine aggregate A to the fine aggregate B (fine aggregate A / fine aggregate B) is 50 to 200%. When the mass ratio is within this range, the effects of the present invention are achieved. From the above perspectives, the mass ratio of the fine aggregate A to the fine aggregate B is more preferably 70 to 180%, and even more preferably 90 to 160%. Here, the mass ratio is the result of dividing the mass of the fine aggregate A by the mass of the fine aggregate B, expressed as a percentage. The particle size and average particle size were determined from the weight passing percentage by sieving.

[0015] <Cement> The cement used in the present invention is not particularly limited, and examples include various cements such as normal, early-strength, ultra-early-strength, low-heat, and moderate-heat cements, various blended cements in which these cements are mixed with blast furnace slag, fly ash, or silica fume, environmentally friendly cements (ecocements) made from municipal waste incineration ash or sewage sludge incineration ash, and commercially available fine particle cements. It is also possible to use various cements and blended cements that have been finely powdered. Furthermore, cements prepared by increasing or decreasing the amount of components (such as gypsum) normally used in cements can also be used. In the present invention, it is preferable to select ordinary Portland cement or high-early-strength Portland cement from the viewpoints of heat of hydration, drying shrinkage, and filling properties.

[0016] The cement used in this invention has a Blaine specific surface area of ​​2,500 cm from the viewpoint of production cost and strength development. 2 / g or more 7,000cm 2 / g or less, and 2 / g or more 6,000cm 2 / g or less is more preferable, and 2 / g or more 4,500cm 2 It is more preferable that the saturation coefficient is 1 / g or less. The Blaine specific surface area value is determined in accordance with JIS R 5201 (physical testing method for cement).

[0017] <Expansive material> The expanding agent used in the present invention is not particularly limited, and any agent can be used as long as it generates an expansive hydrate and suppresses bleeding. Known expansive materials include free lime, free magnesia, calcium ferrite, ettringite, lime, and ettringite-lime composites, and although not particularly limited, those containing free lime are preferred from the viewpoint of long-term stability. Examples of those containing free lime include free lime-anhydrous gypsum systems, free lime-hydraulic compound systems, and free lime-hydraulic compound-anhydrous gypsum systems.

[0018] The expansive material used in this invention preferably contains ternesite. ternesite is a mineral expressed as 5CaO·2SiO2·SO3, and promotes hydraulic reactions. Furthermore, because ternesite itself is virtually unreactive, it is thought to act as a filler, improving fluidity retention. Therefore, fluidity retention can be maintained even at high temperatures. The content of ternesite is preferably 0.05 to 20 parts by mass, more preferably 0.1 to 18 parts by mass, and even more preferably 0.5 to 15 parts by mass, relative to 100 parts by mass of the expanding agent. By keeping the content of ternesite within the above range, both the hardening acceleration and the fluidity retention can be improved.

[0019] In the present invention, it is preferable to use a free lime-hydraulic compound-anhydrous gypsum system because of its good expansion performance, and it is particularly preferable to use a system having a free lime content of more than 40 mass %. Here, examples of the hydraulic compound include one or more of auin, calcium ferrite, calcium aluminoferrite, calcium silicate, calcium aluminate, etc. In the present invention, commercially available expansive materials and static crushing materials can be used as the expansive material. Expansion agents and static crushing agents are commercially available from various companies, and representative examples include Denka CSA#20 and Denka Power CSA manufactured by Denka Co., Ltd., and Expan, Hyperexpan, N-EX, and Blaister manufactured by Pacific Materials Corporation, as well as crushed products of these.

[0020] The particle size of the expanding material used in the present invention is not particularly limited, but it is preferably 2,000 cm 2 or less in terms of Blaine specific surface area. 2 / g or more 25,000cm 2 / g or less is preferable, and 2 / g or more 15,000cm 2 / g or less is more preferable, and 2,400 cm 2 / g or more 10,000cm 2 / g or less is more preferable. When the Blaine specific surface area of ​​the expanding material is equal to or greater than the lower limit, bleeding can be suppressed. When the Blaine specific surface area of ​​the expanding material is equal to or less than the upper limit, sufficient expansion can be obtained.

[0021] The content of the expansive agent used in the present invention is preferably 0.5 to 20 parts by mass, more preferably 1 to 18 parts by mass, and even more preferably 2 to 15 parts by mass, per 100 parts by mass of cement. When the content of the expansive agent is equal to or greater than the lower limit, crack suppression effect is easily achieved. On the other hand, when the content of the expansive agent is equal to or less than the upper limit, strength development is improved. When the content of the expansive agent is within the above range, it is easy to obtain a grout material that satisfies the effects of the present invention, i.e., a grout material that has low heat of hydration, drying shrinkage, and excellent filling properties.

[0022] <Gas foaming material> The gas foaming substance used in the present invention is a substance used for the purpose of preventing the unhardened grout material from sinking or shrinking due to bleeding after application of the grout mortar composition. The gas foaming substance used in the present invention is not particularly limited as long as it generates gas after being mixed with water.

[0023] Examples of gas foaming substances include oily substances such as vegetable oils and mineral oils. Examples of gas foaming substances include powdery substances such as flaky aluminum powder surface-treated with stearic acid and aluminum powder produced by atomization. Examples of gas foaming substances include nitrogen gas foaming substances that foam nitrogen gas in an alkaline atmosphere, such as azo compounds, nitroso compounds, and hydrazine derivatives. Examples of gas foaming substances 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 peroxides such as hydrogen peroxide. As the gas foaming substance used in the present invention, it is preferable to use aluminum powder whose surface has been treated with stearic acid or the like, because this has a great effect of suppressing subsidence.

[0024] The nitrogen gas foaming substance that can be used in the present invention contains a compound that generates nitrogen gas by reacting with alkali generated when cement contained in the grout material is mixed with water, and may also generate gases such as carbon monoxide, carbon dioxide, and ammonia as by-products. The nitrogen gas foaming agent used in the present invention is not particularly limited as long as it can be used to integrate the material with the structure, to prevent the unhardened grout mortar from settling or shrinking, and to improve crack resistance when left in a dry state.

[0025] The content of the gas foaming substance is preferably 0.0001 to 1 part by mass, more preferably 0.0005 to 0.5 parts by mass, and even more preferably 0.001 to 0.2 parts by mass, per 100 parts by mass of cement. By having the content of the gas foaming substance equal to or greater than the lower limit, a sufficient initial expansion effect can be imparted. Furthermore, by having the content of the gas foaming substance equal to or less than the upper limit, strength development is improved.

[0026] <Water reducing agent> The water reducing agent used in the present invention helps disperse each material and also plays a role in imparting fluidity to the mixed grout mortar.

[0027] The water-reducing agent used in the present invention is not particularly limited, and examples thereof include naphthalene-based water-reducing agents, melamine-based water-reducing agents, aminosulfonic acid-based water-reducing agents, and polycarboxylic acid-based water-reducing agents. One or more of these water-reducing agents can be used in the present invention. Specific examples of water-reducing agents include naphthalene-based water-reducing agents such as "Leobuild SP-9 Series" manufactured by NMB Corporation, "Mighty 2000 Series" manufactured by Kao Corporation, and "Sunflow HS-100" manufactured by Nippon Paper Industries Co., Ltd.; melamine-based water-reducing agents such as "Sikament 1000 Series" manufactured by Sika Japan and "Sunflow HS-40" manufactured by Nippon Paper Industries Co., Ltd.; aminosulfonic acid-based water-reducing agents such as "Paric FP-200 Series" manufactured by Fujisawa Pharmaceutical Co., Ltd.; and polycarboxylic acid-based water-reducing agents such as "Leobuild SP-8 Series" manufactured by NMB Corporation, "Darlex Super 100PHX" manufactured by Grace Chemicals, and "Chupol HP-8 Series" and "Chupol HP-11 Series" manufactured by Takemoto Oil & Fat Co., Ltd. Powdered water-reducing agents are also available. Specific examples of naphthalene-based water-reducing agents include "Mighty 100" manufactured by Kao Corporation, "Sanyo Revellon P" manufactured by Sanyo Chemical Industries, Ltd., and "Cellflow 110P" manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd. Melamine-based water-reducing agents include "Melment F10M" manufactured by BASF Pozzolith, Ltd. Polycarboxylic acid-based water-reducing agents include "CAD9000P" manufactured by Kao Corporation.

[0028] The content of the water-reducing agent is preferably 0.1 to 5 parts by mass, more preferably 0.2 to 4 parts by mass, and even more preferably 0.3 to 3.5 parts by mass, in terms of solid content, relative to 100 parts by mass of cement. By having the content of the water-reducing agent be equal to or greater than the lower limit, sufficient fluidity can be obtained. Furthermore, by having the content of the water-reducing agent be equal to or less than the upper limit, material separation can be suppressed.

[0029] <Fine aggregate A> The chemical components of the fine aggregate A used in the present invention preferably contain 85% or more by mass of CaO and 0.2% to 14% by mass of SiO2. When the chemical components of the fine aggregate A contain the CaO and SiO2 proportions within the above ranges, a grout material with low heat of hydration, low drying shrinkage, and excellent filling properties can be obtained. The proportion of CaO 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 proportion of CaO is not particularly limited, but is preferably 99% by mass or less, and more preferably 98.5% by mass or less. The proportion of SiO2 is preferably 0.25 mass % or more and 13 mass % or less, more preferably 0.3 mass % or more and 11 mass % or less, and even more preferably 0.4 mass % or more and 10 mass % or less. To ensure that the chemical composition of fine aggregate A falls within the above and later-described ranges, silica sand, calcite, scapolite, a metamorphic rock, quartz, a igneous rock, potassium feldspar, and other rocks are mixed together to ensure that the chemical composition falls within the ranges specified by the present invention. The chemical composition of fine aggregate A used in the present invention is calculated in terms of oxides.

[0030] The fine aggregate A used in the present invention preferably contains K2O, SO3, Fe2O3, and Al2O3 as chemical components. The inclusion of K2O, SO3, Fe2O3, and Al2O3 in the fine aggregate A can contribute to low heat of hydration, drying shrinkage, and packing properties. The proportion of K2O is preferably 40 ppm by mass or more and 3,000 ppm by mass or less, more preferably 50 ppm by mass or more and 2,500 ppm by mass or less, even more preferably 60 ppm by mass or more and 2,250 ppm by mass or less, and even more preferably 70 ppm by mass or more and 2,000 ppm by mass or less. The proportion of SO3 is preferably 40 mass ppm or more and 3,000 mass ppm or less, more preferably 50 mass ppm or more and 2,500 mass ppm or less, even more preferably 60 mass ppm or more and 2,250 mass ppm or less, and even more preferably 70 mass ppm or more and 2,000 mass ppm or less. The proportion of Fe2O3 is preferably 0.1 mass % or more and 3.0 mass % or less, more preferably 0.13 mass % or more and 2.5 mass % or less, and even more preferably 0.15 mass % or more and 2.0 mass % or less. The proportion of Al2O3 is preferably 0.1 mass % or more and 3.0 mass % or less, more preferably 0.13 mass % or more and 2.5 mass % or less, and even more preferably 0.15 mass % or more and 2.0 mass % or less.

[0031] The fine aggregate A used in the present invention preferably exhibits a reduction in the coarseness ratio of 70% to 100% in accordance with JIS A1121, "Abrasion Test of Coarse Aggregate Using a Los Angeles Tester," more preferably 75% to 99%, even more preferably 80% to 98%, and even more preferably 85% to 97%. When the reduction in the coarseness ratio of fine aggregate A is equal to or greater than the lower limit, packing properties can be improved. Furthermore, when the reduction in the coarseness ratio of fine aggregate is equal to or less than the upper limit, packing properties can be improved. In this specification, the "coarseness ratio of fine aggregate" refers to a value obtained from sieving and is an index that indicates the approximate size of the fine aggregate. In this specification, the "reduction in the coarseness ratio of fine aggregate" refers to the percentage reduction in the coarseness ratio after the Los Angeles test, comparing the coarseness ratio before and after the test. In order to reduce the coarseness ratio of the fine aggregate within the above range, silica sand, calcite, scapolite, which is a metamorphic rock, quartz, which is an igneous rock, potassium feldspar, etc. are mixed to prepare the aggregate. The reduction in the coarseness ratio of the fine aggregate is adjusted by mixing the various rocks while checking the abrasion test of the coarse aggregate using a Los Angeles tester so that it falls within the range of the present invention. As long as the reduction in the coarse particle ratio of the fine aggregate is within the above range, the place of production or the origin of the fine aggregate is not particularly limited.

[0032] The content of fine aggregate A is preferably 50 to 300 parts by mass, more preferably 75 to 250 parts by mass, and even more preferably 150 to 230 parts by mass, per 100 parts by mass of cement. When the content of fine aggregate A is equal to or greater than the lower limit, heat generation can be reduced, shrinkage can be suppressed, and cracking can be suppressed. Furthermore, when the content of fine aggregate is equal to or less than the upper limit, a grout material with excellent filling properties can be obtained.

[0033] <Fine aggregate B> The chemical components of the fine aggregate B used in the present invention preferably contain 75 mass% or more of SiO. By containing 75 mass% or more of SiO as the chemical components of the fine aggregate B, a grout material with low heat of hydration, low drying shrinkage, and excellent filling properties can be obtained. From the above viewpoint, the proportion of SiO2 is more preferably 78 mass % or more, and even more preferably 80 mass % or more. To ensure that the chemical composition of fine aggregate B falls within the above and later-described ranges, silica sand, calcite, scapolite, a metamorphic rock, quartz, a igneous rock, potassium feldspar, and other rocks are mixed together to prepare fine aggregate B. The chemical composition of fine aggregate B is adjusted by mixing the various rocks while checking with fluorescent X-ray diffraction to ensure that it falls within the ranges specified in the present invention. The chemical composition of fine aggregate B used in the present invention is calculated in terms of oxides.

[0034] The content of fine aggregate B is preferably 50 to 300 parts by mass, more preferably 70 to 280 parts by mass, and even more preferably 90 to 250 parts by mass, per 100 parts by mass of cement. When the content of fine aggregate B is equal to or greater than the lower limit, heat generation can be reduced, shrinkage can be suppressed, and cracking can be suppressed. Furthermore, when the content of fine aggregate is equal to or less than the upper limit, a grout material with excellent filling properties can be obtained.

[0035] <Silica fine powder> The grout material of the present invention can contain, in addition to cement, expansive agent, gas foaming substance, water reducing agent, fine aggregate A, and fine aggregate B, silica fine powder in order to improve strength development, acid resistance, ensure usable life, and improve dimensional stability.

[0036] Examples of the siliceous fine powder include latent hydraulic substances such as ground granulated blast furnace slag, fly ash, and pozzolanic substances such as silica fume, with silica fume being preferred. There are no restrictions on the type of silica fume, but from the viewpoint of fluidity, it is preferable to use silica fume containing 10% or less of ZrO2 as an impurity or acidic silica fume. Acidic silica fume is defined as silica fume that, when 1 g of silica fume is added to 100 cc of pure water and stirred, the supernatant liquid has an acidic pH of 5.0 or less.

[0037] The fineness of the silica powder is not particularly limited, but usually, the fine powder of granulated blast furnace slag and fly ash has a Blaine value of 3,000 cm 2 / g or more 9,000cm 2 / g or less, and silica fume has a BET specific surface area of ​​20,000 cm 2 / g or more 300,000 cm 2 It is preferable that the range is 1 / g or less.

[0038] The content of the siliceous fine powder is preferably 1 to 20 parts by mass, more preferably 2 to 15 parts by mass, and even more preferably 3 to 10 parts by mass, per 100 parts by mass of cement. Having the content of the siliceous fine powder equal to or greater than the lower limit mentioned above can improve strength development, acid resistance, ensure usable life, and dimensional stability. Having the content of the siliceous fine powder equal to or less than the upper limit mentioned above can improve fluidity, adhesion to reinforcing bars, and rust prevention.

[0039] In the present invention, one or more of the following additives may be used to the extent that they do not adversely affect performance: setting regulators, air-entraining agents, rust inhibitors, water repellents, antibacterial agents, colorants, antifreeze agents, admixtures such as fine limestone powder, slowly cooled blast furnace slag powder, sewage sludge incineration ash and its molten slag, municipal waste incineration ash and its molten slag, and pulp sludge incineration ash; antifoaming agents; thickeners; shrinkage reducing agents; fibrous materials such as steel fiber, vinylon fiber, carbon fiber, and wollastonite fiber; polymers; clay minerals such as bentonite and sepiolite; and anion exchangers such as hydrotalcite.

[0040] In the grout material of the present invention, the method of mixing the materials is not particularly limited, and the materials may be mixed at the time of application, or some or all of the materials may be mixed in advance. As the mixing device, any existing device such as a tilting mixer, an omni mixer, a Henschel mixer, a V-type mixer, or a Nauta mixer can be used.

[0041] <Grout mortar composition> The grout mortar composition of the present invention contains the grout material of the present invention described above and water, and is prepared by kneading the grout material and water. The amount of mixing water in the present invention is not particularly limited, as it varies depending on the purpose and application of use and the content ratio of each material, but is preferably 5 to 70 parts by mass, more preferably 7 to 65 parts by mass, and even more preferably 9 to 60 parts by mass, per 100 parts by mass of grout material. By keeping the amount of mixing water at or above the above lower limit, it is possible to prevent a decrease in fluidity and prevent the heat generation from becoming extremely large. Furthermore, by keeping the amount of mixing water at or below the above upper limit, it is possible to ensure strength development.

[0042] In the present invention, the method for mixing 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-screw forced mixer.

[0043] When mixing with a hand mixer or high-speed grout mixer, it is preferable to first add a certain amount of water to a container such as a pail or mixer, then add the grout material while rotating the mixer, and mix for at least 3 minutes. When mixing with a forced mixer, it is preferable to first add the grout material to the mixer, then add the certain amount of water while rotating the mixer, and mix for at least 4 minutes. Mixing for less than the specified time may result in insufficient mixing, making it difficult to obtain the appropriate fluidity of the grout mortar.

[0044] <Cured body> The mixed grout mortar composition is usually pumped to the application site using a manual injection gun, a diaphragm hand pump, or a squeeze type mortar pump, and then filled and applied to form a hardened body using the grout mortar composition of the present invention. [Example]

[0045] The present invention will be further explained below based on experimental examples of the present invention, but the present invention is not limited to these.

[0046] Experimental Example 1 (No. 1-1 to 1-9) A grout material was prepared containing 12.0 parts by mass of expansive material, 0.0025 parts by mass of gas foaming material, 1.5 parts by mass of water reducing agent, and 300 parts by mass of fine aggregate (A+B) per 100 parts by mass of cement. 100 parts by mass of the obtained grout material was mixed with 15 parts by mass of water to prepare a grout mortar composition. The prepared grout mortar compositions were measured for simple adiabatic temperature rise, drying shrinkage, and filling properties. The results are shown in Table 1. Drying shrinkage was expressed as change in length. The larger the absolute value of the numerical value, the larger the drying shrinkage.

[0047] <Materials used> Cement: Trial cement (various commercially available pure chemicals were used to adjust the raw materials and chemical components of the cement factory, and pure anhydrous gypsum was used to adjust the amount of SO3), chlorine content 1.5 mass% ppm, Blaine value 3,450 cm 2 / g Expanding agent: CaO raw material, Al2O3 raw material, SiO2 raw material, and CaSO4 raw material are mixed and crushed, then fired at 1,200°C to synthesize clinker, which is then crushed in a ball mill to a Blaine specific surface area of ​​3,000 cm 2 The mineral composition of ternesite was calculated based on the chemical composition determined from fluorescent X-rays and the results of powder X-ray diffraction analysis. The amount of ternesite contained in 100 parts by mass of the expansive additive is shown in Table 1. Gas foaming material: flaky aluminum powder surface-treated with stearic acid, commercially available · Setting agent: A mixture of 25 parts reagent grade citric acid and 75 parts reagent grade potassium carbonate Water reducing agent: Naphthalene-based water reducing agent, commercially available (Dai-ichi Kogyo Seiyaku Co., Ltd. "Selflo-110P") Water: Tap water Fine aggregates A and B: Tests were conducted using the fine aggregates shown in Table 1. The chemical composition of the fine aggregates was measured by fluorescent X-ray analysis. In addition, to prepare the chemical composition, silica sand (produced in Aichi Prefecture), calcite (CaCO3), and scapolite ((Na, Ca, K)4Al4Si9O 24 The chemical composition was prepared by mixing igneous rocks (Cl, CO3, SO4), quartz (SiO2), and potassium feldspar (KAlSi3O8). The average particle size is a value determined from the weight passing percentage by the sieving method as described above.

[0048] <Measurement items> - Simple adiabatic temperature rise: The maximum temperature was measured immediately after mixing in a simple 2L pot. Length change (drying shrinkage): The length change was measured at 28 days of age in accordance with JIS A 6202. Static flow: Based on JIS R 5201, measurements were taken immediately after mixing and after 15 and 30 minutes. Filling rate: A 1000 x 1000 mm acrylic plate was fixed at a height of 100 mm in the center of a 1200 x 1200 mm formwork. The hose nozzle was inserted into the back of the gap and the concrete was filled in while being pulled toward the front. After filling, the volume of the void was measured.

[0049] [Table 1]

[0050] The results in Table 1 confirm that by using grout material with a specific angle of repose that contains two types of fine aggregate with specific particle sizes in a specific ratio, it is possible to reduce hydration heat and drying shrinkage and improve filling properties.

[0051] Experimental Example 2 (No. 1-3, No. 2-1 to 2-4) The same procedure as in Experimental Example 1 was carried out, except that the grout mortar composition was prepared by blending the fine aggregate shown in Table 2. The results are also shown in Table 2. The amount of ternesite used in the expansive additive was 5 parts by mass per 100 parts by mass of the expansive additive. The abrasion test for fine aggregate using the Los Angeles tester begins with loading 5 kg of fine aggregate A and six iron balls. The iron balls have an average diameter of approximately 46.8 mm and a mass of 390 to 445 g each. The Los Angeles tester is then rotated at 500 revolutions per minute (30 revolutions per minute). The fine aggregate sampled from the Los Angeles tester is then sieved using metal mesh sieves with mesh sizes of 5 mm, 2.5 mm, 1.2 mm, 0.6 mm, 0.3 mm, and 0.15 mm. The coarseness ratio (R1) of fine aggregate A before loading into the Los Angeles tester and the coarseness ratio (R2) of fine aggregate A after loading into the Los Angeles tester are compared, and the decrease in coarseness ratio after the test is calculated using the following formula. Note that the coarseness ratios R1 and R2 were calculated in accordance with JIS A 1102. Reduction in coarse grain ratio = R2 / R1 The grout materials used in Nos. 2-1 to 2-4 had the same composition as in No. 1-3. That is, the particle size, average particle size, fine aggregate A / fine aggregate B (mass ratio), and angle of repose of fine aggregate A and fine aggregate B were the same as in No. 1-3.

[0052] [Table 2]

[0053] From the results in Table 2, it was confirmed that by using a grout material with a specific angle of repose that contains two types of fine aggregate with specific particle sizes in a specific ratio, and that contains fine aggregate with specific chemical components and a specific range of reduction in coarseness, it is possible to reduce hydration heat and drying shrinkage and improve filling properties.

[0054] Experimental Example 3 (No. 1-3, No. 3-1 to 3-4) The same procedure as in Experimental Example 1 was carried out except that the grout mortar composition was prepared by blending the fine aggregates shown in Table 3. The results are also shown in Table 3. The grout materials used in Nos. 3-1 to 3-4 had the same composition as in No. 1-3. That is, the particle size, average particle size, fine aggregate A / fine aggregate B (mass ratio), and angle of repose of fine aggregate A and fine aggregate B were the same as in No. 1-3.

[0055] [Table 3]

[0056] The results in Table 3 confirm that by using grout material with a specific angle of repose that contains two types of fine aggregate with specific particle sizes and specific chemical compositions in a specific ratio, it is possible to reduce hydration heat and drying shrinkage and improve filling properties. [Industrial Applicability]

[0057] The grout material of the present invention is prepared by combining specific fine aggregates, and provides a grout mortar composition that can reduce hydration heat and drying shrinkage and improve filling properties. Therefore, this grout mortar composition can be used in a wide range of applications, including steel plate wrapping methods for bridge piers, filling methods for large support seats, anchoring materials for reinforcing steel bars, other gap filling methods, concrete cross-section repair, self-leveling flooring materials, and civil engineering and construction applications.

Claims

1. A grout material containing cement, an expansive agent, a gas foaming agent, a water reducing agent, fine aggregate A, and fine aggregate B, the particle size of the fine aggregate A is less than 1.2 mm and has an average particle size of 0.4 to 0.8 mm, the particle size of the fine aggregate B is in the range of 1.2 to 10 mm and has an average particle size of 2 to 9 mm, and the mass ratio of the fine aggregate A to the fine aggregate B (fine aggregate A / fine aggregate B) is 50 to 200%, The chemical components of the fine aggregate A include a CaO content of 85% by mass or more and a SiO 2 content of 0.2% by mass or more and 14% by mass or less. The chemical composition of the fine aggregate B is such that the proportion of SiO 2 is 75 mass% or more, A grout material with an angle of repose of 40 to 55 degrees.

2. The expanding material contains ternesite, The grout material according to claim 1, wherein the content of the ternesite is 0.05 parts by mass or more and 20 parts by mass or less per 100 parts by mass of the expansive agent.

3. 3. The grout material according to claim 1, wherein the fine aggregate A has a reduction in coarseness ratio of 70% or more and 100% or less according to JIS A1121 "Abrasion test of coarse aggregate using a Los Angeles tester."

4. The chemical composition of the fine aggregate A is K ２ The ratio of O is 40 mass ppm or more and 3,000 mass ppm or less, and SO ３ The grout material according to any one of claims 1 to 3, wherein the ratio of is 40 ppm by mass or more and 3,000 ppm by mass or less.

5. The chemical composition of the fine aggregate A is Fe. ２ O ３ The proportion of Al is 0.1 mass% or more and 3.0 mass% or less. ２ O ３ The grout material according to any one of claims 1 to 4, wherein the proportion of is 0.1% by mass or more and 3.0% by mass or less.

6. The grout material according to any one of claims 1 to 5, wherein the content of the fine aggregate A is 50 parts by mass or more and 300 parts by mass or less relative to 100 parts by mass of the cement, and the content of the fine aggregate B is 50 parts by mass or more and 300 parts by mass or less relative to 100 parts by mass of the cement.

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

8. A hardened body obtained by using the grout mortar composition according to claim 7.

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