JP2010229009A - Self-fluidity hydraulic composition, self-fluidity hydraulic mortar and concrete floor structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a self-fluidity hydraulic composition capable of stably keeping high fluidity for a long period of time, having excellent quick hardening property and horizontal leveling property, and capable of attaining excellent surface finishing property. <P>SOLUTION: The self-fluidity hydraulic composition having self fluidity contains: a hydraulic component, fine aggregate and a fluidizing agent. The fine aggregate contains <5 mass% coarse particle having ≥600 μm particle diameter in the fine aggregate (100 mass%) and water absorption of the fine aggregate is ≤1.6%. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a self-flowing hydraulic composition used for construction of a structure such as a concrete floor structure, a self-flowing hydraulic mortar using the same, and a concrete floor structure having the same.

  Self-flowing hydraulic compositions used as self-leveling materials have high fluidity, flow retention and separation resistance to ensure self-smoothness and surface accuracy, and are fast enough to allow early opening. From the aspect of hardness and ease of construction work, it is required to have an appropriate pot life.

  As a self-flowing hydraulic composition having high fluidity, maintaining sufficient pot life and good cured surface finish, Patent Document 1 includes aluminum sulfate and lithium salt as a setting accelerator, A self-flowing hydraulic composition containing 3 to 20% by weight of fine particles of 30 to 150 μm and 97 to 80% by weight of particles of 150 to 850 μm in 100% by weight as a material is disclosed.

  Patent Document 2 includes potassium sulfate and a lithium salt. As fine aggregate, 3 to 20% by mass of fine particles of 30 μm to less than 150 μm in 100% by mass, and 97 to 95 μm of particles having a particle size of 150 μm to less than 850 μm. A self-flowing hydraulic composition containing 80% by weight is disclosed.

  Further, as a self-smoothness of cement capable of stably obtaining fluidity suitable for obtaining self-smoothness by suppressing material separation, Patent Document 3 discloses that the particle content of less than 150 μm is 70% by volume. A cement-based self-smooth composition having a particle content of 5% or more and a hydration reaction rate of 5% or more after 24 hours of water contact is 10 to 35% by volume.

JP 2008-162837 A JP 2008-162836 A JP 2008-037677 A

  The present invention provides a self-flowing hydraulic mortar that can maintain a stable and high fluidity for a long period of time, has excellent fast-hardness and horizontal level properties, and has a self-flowing property that provides a good surface finish. It aims at providing a water-soluble hydraulic composition.

  The present inventors have intensively studied the influence of fine aggregate properties on the properties of mortar and mortar using a hydraulic composition, particularly the influence of fine aggregate particle size distribution and water absorption rate. As a result, the present invention has been completed.

  That is, the first of the present invention is a self-flowing hydraulic composition containing a hydraulic component, fine aggregate, and a fluidizing agent, and the fine aggregate is 600 μm in the fine aggregate (100% by mass). It is a self-flowing hydraulic composition containing less than 5% by mass of coarse particles having the above particle diameter and having a fine aggregate water absorption of 1.6% or less.

  The second of the present invention is a self-flowing hydraulic mortar obtained by kneading the self-flowing hydraulic composition of the present invention and water.

  3rd of this invention is a concrete floor structure which has the hardening body layer of the self-flowing hydraulic mortar of this invention in a surface layer.

Preferred embodiments of the self-flowing hydraulic composition of the present invention are shown below. A plurality of preferred embodiments can be combined.
1) The fine aggregate has a coarse particle ratio in the range of 1.00 to 1.40, the fine aggregate has a unit volume mass in the range of 1.45 to 1.70 kg / L, and the fine aggregate performance rate Is in the range of 55.0 to 61.0%.
2) The hydraulic component (100% by mass) is composed of 20-80% by mass of alumina cement, 5-70% by mass of Portland cement, and 5-45% by mass of gypsum.
3) The self-flowing hydraulic composition further contains at least one component selected from inorganic components, setting retarders, resin powders, thickeners and antifoaming agents.
4) The flow value of the self-flowing hydraulic mortar prepared by kneading the self-flowing hydraulic composition and water is in the range of 210 to 240 mm, and is mixed immediately after the self-flowing hydraulic mortar is kneaded. The SL value up to 30 minutes after kneading is in the range of 400 to 600 mm, and the SL value (L20) at the time 20 minutes after kneading with respect to the SL value (L0) immediately after kneading of the self-flowing hydraulic mortar and The ratio of the SL value (L30) after 30 minutes after kneading is normalized to L0 = 100 is in the range of 100 to 120.
5) The self-flowing hydraulic mortar prepared by kneading the self-flowing hydraulic composition and water has a shore hardness of 10% after 3 hours after applying the self-flowing hydraulic mortar. That's it.

  According to the present invention, it is possible to maintain a stable and high fluidity for a long time, a self-flowing hydraulic mortar capable of obtaining a self-flowing hydraulic mortar capable of obtaining a good surface finish, excellent in quick hardening and horizontal level properties. A composition can be provided.

It is a schematic diagram which shows the outline of self-leveling evaluation of mortar using SL measuring device.

  The present invention is a self-flowing hydraulic composition comprising a hydraulic component, a fine aggregate, and a fluidizing agent, wherein the fine aggregate has a small amount of coarse particles having a particle diameter of 600 μm or more, The present invention relates to a self-flowing hydraulic composition having a water absorption of 1.6% or less. The fine aggregate contained in the self-flowing hydraulic composition of the present invention preferably has a coarse particle ratio in the range of 1.00 to 1.40 and a unit volume mass of 1.45 to 1.70 kg / L. The performance rate is in the range of 55.0 to 61.0%.

  In the present invention, the particle size of the fine aggregate is measured using several sieves having different nominal dimensions as defined in JIS Z8801: 2006. In the present invention, the term “coarse particles having a particle diameter of 600 μm or more” refers to the mass ratio of the remaining particles when a 600 μm sieve is used. The “water absorption rate” refers to the water absorption rate (unit:%) of the aggregate as defined in JIS A1109: 2006. “Coarse grain ratio” refers to the coarse grain ratio of the aggregate defined in JIS A1102: 2006. The “unit volume mass” refers to the unit volume mass (unit: kg / L) of the aggregate defined in JIS A1104: 2006. The “actual rate” refers to the actual rate (unit:%) of the aggregate defined in JIS A1104: 2006.

  As the hydraulic component contained in the self-flowing hydraulic composition of the present invention, a hydraulic component containing a cement component and gypsum can be used. As a cement component, it can select and use from Portland cement, an alumina cement, etc.

  Portland cements used for hydraulic components include ordinary Portland cement, early-strength Portland cement, ultra-early strong Portland cement, moderately hot Portland cement, low heat Portland cement and white Portland cement, and blast furnace cement, fly ash cement and It can be used by selecting from mixed cement such as silica cement.

  Several types of alumina cements with different mineral compositions are known and commercially available for use as hydraulic components, but the main component is monocalcium aluminate (CA). Can be used.

  In the self-flowing hydraulic composition of the present invention, gypsum can be used as one of the hydraulic components. Gypsum functions as a component that retains dimensional stability after the mortar obtained by kneading the self-flowing hydraulic composition and water is cured.

  As the gypsum used in the self-flowing hydraulic composition of the present invention, either gypsum produced as a by-product in a hydrofluoric acid production process or the like, or gypsum produced in nature can be used.

  In the present invention, a hydraulic component made of alumina cement, Portland cement and gypsum is used as the hydraulic component, and has excellent self-fluidity, proper pot life, and excellent fast-curing property. It is preferable because a fluid hydraulic composition is obtained.

  The hydraulic component of the self-flowing hydraulic composition of the present invention is preferably 20 to 80 parts by mass of alumina cement and 5 to 70 parts of Portland cement when the total mass of alumina cement, Portland cement and gypsum is 100 parts by mass. A composition consisting of 5 parts by mass and gypsum, more preferably 30 to 70 parts by mass of alumina cement, 15 to 60 parts by mass of Portland cement and 10 to 40 parts by mass of gypsum, more preferably 35 to 60 alumina cement. A composition comprising mass parts, 20 to 50 parts by mass of Portland cement and 15 to 35 parts by mass of gypsum, particularly preferably a composition comprising 40 to 50 parts by mass of alumina cement, 25 to 40 parts by mass of Portland cement and 17 to 27 parts by mass of gypsum. It is preferable to use it. By setting it as such a composition, the hydraulic mortar (self-flowing hydraulic mortar) which is excellent in self-fluidity can be obtained, and also has a rapid curing, low shrinkage or low expansion and volume during curing. This is because it becomes easy to obtain a cured body with little change.

  The self-fluid hydraulic composition of the present invention includes a hydraulic component, fine aggregate, and a fluidizing agent. The fine aggregate is preferably 30 to 500 parts by mass, more preferably 50 to 400 parts by mass, still more preferably 100 to 300 parts by mass, and particularly preferably 150 to 250 parts by mass with respect to 100 parts by mass of the hydraulic component. Is preferred.

  As the particle size of the fine aggregate contained in the self-flowing hydraulic composition of the present invention, the coarse particle having a particle diameter of 600 μm or more, preferably containing less than 5% by mass of the same coarse particle, more preferably Is preferably composed mainly of a material containing less than 3% by mass of the same coarse particles, more preferably a material containing less than 0.15% by mass of the same coarse particles. The lower limit of the coarse particles is not particularly limited, and the coarse particles having a particle diameter of 600 μm or more may be 0% by mass.

  In order to obtain excellent self-fluidity, the water absorption rate of the fine aggregate contained in the self-fluidic hydraulic composition of the present invention is preferably 1.60% or less, more preferably 1.40% or less, and still more preferably Is preferably 1.28% or less as a main component. The lower limit of the water absorption rate of the fine aggregate is not particularly limited, and the water absorption rate may be 0%.

  Further, in order to obtain excellent self-fluidity, the coarse particle ratio of the fine aggregate contained in the self-fluidic hydraulic composition of the present invention is preferably 1.00 to 1.40, more preferably 1. It is preferable that it is 10-1.35, More preferably, it is 1.12-1.30.

  In order to obtain excellent self-fluidity, the unit volume mass of the fine aggregate contained in the self-fluidic hydraulic composition of the present invention is preferably 1.45 to 1.70 kg / L, more preferably 1 .50 to 1.60 kg / L, more preferably 1.52 to 1.55 kg / L.

  Further, in order to obtain excellent self-fluidity, the actual rate of fine aggregate contained in the self-fluidic hydraulic composition of the present invention is preferably 55.0 to 61.0%, more preferably 56. It is preferably 0 to 60.0%, more preferably 57.0 to 59.0%.

  Fine aggregates include silica sand, river sand, sea sand, mountain sand and crushed sand, alumina clinker, silica powder, clay mineral, waste FCC catalyst and inorganic materials such as limestone, urethane crushed, EVA foam and foaming resin It can select suitably from resin pulverized materials etc., such as. In particular, as the fine aggregate, those selected from sands such as quartz sand, river sand, sea sand, mountain sand and crushed sand, waste FCC catalyst, quartz powder, alumina clinker and the like can be preferably used.

  The self-flowing hydraulic composition of the present invention includes a fluidizing agent (water reducing agent such as a high-performance water reducing agent) that ensures suitable fluidity while suppressing material separation. Since the expression strength of alumina cement, which is a hydraulic component, is greatly affected by the water / cement ratio, it is particularly preferable to reduce the water / hydraulic component ratio by using a fluidizing agent having a water reducing effect.

  As the fluidizing agent, commercially available fluidizing agents such as formaldehyde condensate of melamine sulfonic acid, casein, casein calcium, polycarboxylic acid-based, polyether-based and polyether polycarboxylic acid-based, which have a water reducing effect, are included. It can be used regardless of the type, and it is particularly preferable to use commercially available fluidizing agents such as polyether-based and polyether polycarboxylic acid.

  The fluidizing agent can be appropriately added in a range that does not impair the characteristics, depending on the hydraulic component used, and is preferably 0.01 to 2.0 parts by mass, more preferably 100 parts by mass with respect to the hydraulic component. May be blended in an amount of 0.05 to 1.0 part by mass, more preferably 0.1 to 0.5 part by mass. If the amount added is too small, no suitable effect (excellent fluidity and high cured product strength) will be exhibited, and if the amount added is too large, an effect commensurate with the amount added cannot be expected, and it is merely uneconomical. In some cases, the viscosity increases and the amount of kneading water for obtaining the required fluidity increases to deteriorate the strength properties.

  The self-flowing hydraulic composition of the present invention includes a hydraulic component composed of alumina cement, Portland cement and gypsum, a fine aggregate, and a fluidizing agent, and further includes an inorganic component, a setting retarder, a setting accelerator, It is preferable to include one or more components selected from thickeners and antifoaming agents.

  The self-fluid hydraulic composition of the present invention contains at least one inorganic component selected from blast furnace slag fine powder, fly ash and silica fume, and in particular, a cured product due to drying shrinkage by containing the blast furnace slag fine powder. The crack resistance can be improved. In the self-flowing hydraulic composition of the present invention, the amount of the inorganic component added is preferably 10 to 350 parts by mass, more preferably 30 to 200 parts by mass, and still more preferably 50 to 100 parts by mass with respect to 100 parts by mass of the hydraulic component. 150 parts by mass, particularly preferably 70 to 130 parts by mass is preferable.

In the self-flowing hydraulic composition of the present invention, the amount of blast furnace slag fine powder added is preferably 10 to 350 parts by mass, more preferably 30 to 200 parts by mass, and still more preferably, with respect to 100 parts by mass of the hydraulic component. 50 to 150 parts by mass, particularly preferably 70 to 130 parts by mass is preferable. This is because if the addition amount of the blast furnace slag fine powder is too small, the drying shrinkage of the cured body increases, and if it is too large, the initial strength may be lowered. As the blast furnace slag fine powder, those having a brain specific surface area of 3000 cm ² / g or more as defined in JIS A 6206 can be used.

  The setting modifier can be added as appropriate within the range that does not impair the properties, depending on the hydraulic component and self-flowing hydraulic composition used, and the components, addition amount and mixing ratio of the setting retarder and the setting accelerator. Can be appropriately selected to adjust the pot life and fast setting of the self-flowing hydraulic composition.

  As the setting retarder, a known setting retarder can be used. Examples of setting retarders include organic acids typified by oxycarboxylic acids such as tartaric acids, malic acids, citric acids and gluconic acids, sodium sulfate, sodium bicarbonate, sodium phosphate, sodium polyphosphate and sodium tripolyphosphate These inorganic sodium salts can be used alone or in combination of two or more components.

  Oxycarboxylic acids include oxycarboxylic acids and their salts. Examples of the oxycarboxylic acid include aliphatic oxyacids such as citric acid, gluconic acid, tartaric acid, glycolic acid, lactic acid, hydroacrylic acid, α-oxybutyric acid, glyceric acid, tartronic acid, malic acid, salicylic acid, and m-oxybenzoic acid. Examples thereof include aromatic oxyacids such as acid, p-oxybenzoic acid, gallic acid, mandelic acid and tropic acid.

  Examples of the oxycarboxylic acid salt include alkali metal salts (specifically sodium salt and potassium salt) of oxycarboxylic acid and alkaline earth metal salts (specifically calcium salt, barium salt and magnesium salt). The sodium salt is more preferable. In particular, sodium bicarbonate and monosodium tartrate are preferable from the standpoint of setting delay effect, availability, and cost, and it is more preferable to use these in combination.

  The setting retarder contained in the self-flowing hydraulic composition of the present invention is preferably 0.01-2 parts by mass, more preferably 0.1-1.5 parts per 100 parts by mass of the hydraulic component. The pot life (handling time) with which suitable fluidity is obtained can be ensured by using in the range of parts by mass, more preferably 0.2 to 1.2 parts by mass, particularly preferably 0.4 to 1 part by mass. preferable. Furthermore, by adjusting the addition amount of the setting retarder to the above preferred range, a mortar having self-fluidity (self-leveling property) and having a pot life (handling time) capable of obtaining suitable fluidity is obtained. It is preferable because it can be obtained.

  As the setting accelerator contained in the self-flowing hydraulic composition of the present invention, a known component for promoting setting can be used. As the setting accelerator, for example, a lithium salt having a setting acceleration effect and a sulfate such as aluminum acid can be preferably used, and several kinds of these can be used in combination.

  Examples of lithium salts include inorganic lithium salts such as lithium carbonate, lithium chloride, lithium sulfate, lithium nitrate and lithium hydroxide, and organic acid organics such as lithium oxalate, lithium acetate, lithium tartrate, lithium malate and lithium citrate. A lithium salt etc. can be mentioned. In particular, lithium carbonate is preferable from the viewpoint of the setting acceleration effect, availability, and cost.

  As the setting accelerator, those having a particle size that does not interfere with the characteristics of the self-flowing hydraulic composition are preferably used, and the particle size is preferably 50 μm or less. Particularly when a lithium salt is used, the particle diameter of the lithium salt is preferably 50 μm or less, more preferably 30 μm or less, and even more preferably 10 μm or less. When the particle diameter of the lithium salt is larger than the above range, the solubility of the lithium salt becomes small, which is not preferable. In particular, in the pigment addition system, it is noticeable as a large number of fine spots, and the appearance may be impaired.

  The setting accelerator is preferably 0.01 to 1 part by weight, more preferably 0.01 to 0.5 part by weight, and further preferably 0.02 to 0.4 part by weight with respect to 100 parts by weight of the hydraulic component. It is preferable to use in the range of part by mass, particularly preferably in the range of 0.04 to 0.3 part by mass, since a suitable quick setting can be obtained after securing the pot life of the self-flowing hydraulic composition. By adjusting the addition amount of the setting accelerator within the above-mentioned preferable range, a mortar having self-fluidity (self-leveling property) and securing a good pot life is obtained, and a suitable fast-curing property is obtained. This is preferable.

  The thickening agent contained in the self-flowing hydraulic composition of the present invention contains hydroxyethyl methylcellulose, other cellulose-based excluding hydroxyethylmethylcellulose, modified starch such as starch ether, protein-based, latex-based and water-soluble A thickener such as a polymer can be used in combination. The addition amount of the thickener can be added within a range that does not impair the characteristics of the self-flowing hydraulic composition of the present invention. Specifically, the amount is preferably 0.001 to 2 parts by mass, more preferably 0.01 to 1.5 parts by mass, still more preferably 0.05 to 1 part by mass, particularly 100 parts by mass of the hydraulic component. Preferably 0.1 to 0.6 parts by mass are included. When the addition amount of the thickener is increased, the mortar viscosity is increased and the fluidity may be lowered. Therefore, it is preferably used in the above preferred range.

  In the self-flowing hydraulic composition of the present invention, it is used in combination with a thickener and an antifoaming agent to suppress separation of aggregates such as hydraulic components and fine aggregates, suppression of bubble generation, and the surface of the cured body This is preferable for improving the properties of the self-flowing hydraulic composition and improving the properties of the cured product.

  As the antifoaming agent contained in the self-flowing hydraulic composition of the present invention, a known material such as a synthetic material such as silicon-based, alcohol-based or polyether-based material, mineral oil-based material, or plant-derived natural material should be used. Can do. The addition amount of the antifoaming agent can be added within a range that does not impair the characteristics of the self-flowing hydraulic composition of the present invention, and is preferably 0.001 to 2 parts by mass with respect to 100 parts by mass of the hydraulic component. More preferably, it is 0.01-1.5 mass parts, More preferably, it is 0.05-1 mass part, Especially preferably, it is preferable to contain 0.1-0.5 mass part. The addition amount of the antifoaming agent is preferably within the above range because a suitable antifoaming effect is recognized.

  In the self-flowing hydraulic composition of the present invention, a shrinkage reducing agent, a resin powder, and the like can be appropriately selected and used when the effect of preventing and suppressing dry cracks is further increased.

  In the case of constituting the self-flowing hydraulic composition of the present invention, particularly suitable component constitutions are hydraulic components composed of alumina cement, Portland cement and gypsum, fine aggregates such as dredged sand, fluidizing agents, inorganic components, It includes a setting modifier, a thickener and an antifoaming agent.

  The self-fluid hydraulic composition of the present invention is prepared by mixing a predetermined hydraulic component and inorganic component, fine aggregate, fluidizing agent, inorganic component, setting modifier, thickener, antifoaming agent and the like with a mixer. A premix powder of the product can be obtained.

  The premix powder of the self-flowing hydraulic composition can produce hydraulic mortar (self-flowing hydraulic mortar) having self-fluidity by mixing and stirring with a predetermined amount of water. Moreover, the hardening body of a self-flowing hydraulic mortar can be obtained by hardening the self-flowing hydraulic mortar.

  The self-flowing hydraulic composition can produce a self-flowing hydraulic mortar by mixing and stirring with water. At this time, by adjusting the amount of water added, the fluidity, pot life, material separability, strength of the cured product, and the like of the self-flowing hydraulic mortar can be adjusted.

  The amount of water added is preferably 10 to 40 parts by mass, more preferably 14 to 34 parts by mass, still more preferably 18 to 30 parts by mass, and particularly preferably 22 to 100 parts by mass with respect to 100 parts by mass of the self-flowing hydraulic composition. It is preferable to add and use within the range of 28 parts by mass in order to obtain appropriate fluidity.

  The flow value of the self-flowing hydraulic mortar prepared by kneading with water is preferably 210 to 240 mm, more preferably 210 to 230 mm, and still more preferably 210 to 225 mm. It is preferable that it is adjusted for the reason that it is easy to construct and that it is easy to obtain a hardened body surface with high smoothness and high hardness.

  Furthermore, the SL value (L20) at the time 20 minutes after kneading and the SL value (L30) at the time 30 minutes after kneading with respect to the SL value (L0) immediately after kneading of the self-flowing hydraulic mortar, L0 = The ratio when normalized to 100 is preferably adjusted to a range of 100 to 120, more preferably 100 to 115, to obtain a hardened body surface that is easy to construct and has high smoothness and high hardness. This is preferable because it is easily formed.

  The self-flowing hydraulic mortar of the present invention starts curing within 0.5 to 3 hours after completion of construction, and the surface hardness of the cured body increases with the progress of curing, and the moisture content on the surface of the cured body Decreases. The shore hardness of the cured body surface of the self-flowing hydraulic mortar is preferably 10 or more after 3 hours, more preferably 20 or more after 3 hours, more preferably 30 or more after 3 hours, especially from the placement (construction) of the mortar. Preferably, a value of 40 or more is obtained after 3 hours, and after the slurry construction is completed, the construction of the self-flowing hydraulic mortar can be completed by rapidly proceeding with the curing.

  When the self-flowing hydraulic composition of the present invention is used, a self-flowing hydraulic mortar that can stably maintain high fluidity for a long time can be obtained. The self-flowing hydraulic mortar of the present invention has good handling properties, and is excellent in fast curing and surface smoothness and accuracy, and can stably obtain a cured product having a good finished surface. . When the self-fluid hydraulic mortar of the present invention is used as a self-leveling material by taking advantage of excellent self-fluidity, it is used in schools, condominiums, convenience stores, hospitals, verandas, factories, warehouses, parking lots, gas stations, kitchens and It can be used for flooring such as rooftops and floor finishing materials.

  Hereinafter, the present invention will be described in more detail based on examples. However, the present invention is not limited by the following examples.

(1) Mortar evaluation:
As the mortar used for evaluation, a hydraulic mortar immediately after kneading prepared by kneading a hydraulic composition and water is used.

-Self-leveling property (self-fluidity): flow value and SL value The flow value is measured according to JASS 15M-103. A pipe made of vinyl chloride (internal volume: 100 ml) having an inner diameter of 50 mm and a height of 51 mm is placed on a glass sheet having a thickness of 5 mm, filled with the kneaded hydraulic mortar composition, and then the pipe is pulled up. After the spread has stopped, the diameters in two perpendicular directions are measured, and the average value is taken as the flow value.

SL value SL value uses SL (self-leveling) measuring device shown in FIG. 1, a rail 30 mm wide × 30 mm high × 750 mm long is provided with a weir plate at a length of 150 mm from the tip, A predetermined amount of mortar immediately after kneading is filled and molded. Pull up the weir plate immediately after molding and after the mortar flow stops, measure the distance from the gauge point (the part where the dam plate is installed) to the part closest to the gauge point (shortest part) at the tip of the hydraulic mortar flow, The value (SL value) is L0.

  Similarly, after 10 minutes, 20 minutes or 30 minutes after molding, the weir plate is pulled up, and after the mortar flow is stopped, the distance from the gauge point (the installation portion of the weir plate) to the shortest part of the mortar flow is measured. (SL value) is set to L10, L20, or L30. An index normalized with the value of L0 so that L0 = 100 is referred to as an SL value index.

-Flow rate In the measurement of SL value, the flow rate is defined as the number of seconds (s / 200 mm) from when the weir plate is pulled up until the moving distance of the tip of the mortar flow reaches 200 mm.

-Evaluation conditions The above evaluation is performed in an environment of a temperature of 20 ° C and a humidity of 65%.

(2) The state of the cured body surface The condition of the surface of the cured mortar body is that the prepared hydraulic mortar is poured into a 13 cm × 19 cm resin mold at a thickness of 10 mm, and the surface is 24 hours after curing. The finish was evaluated by visual observation. Evaluation was as follows. Evaluation conditions are performed in an environment of a temperature of 20 ° C. and a humidity of 65%.
○: No irregularities, ×: Irregularities.

(3) Shore hardness of the cured body surface After a predetermined elapsed time after placing the hydraulic mortar, the hardness of the cured surface can be arbitrarily determined using a spring type hardness meter type D (manufactured by Ueshima Seisakusho Co., Ltd.). The surface hardness at the four locations is measured, and the average value of the reading values of the spring type hardness tester type D gauge is defined as the surface hardness at that time. In the case of Examples and Comparative Examples of the present invention, the Shore hardness after 3 hours was measured.

The following materials were used.
1) Hydraulic component-Alumina cement (Fonju, Kerneos, Blaine specific surface area 3100 cm ² / g).
Portland cement (early strong cement, manufactured by Ube Mitsubishi Cement Co., Ltd., Blaine specific surface area 4500 cm ² / g).
Gypsum: natural anhydrous gypsum (Blaine specific surface area 4500 cm ² / g).
2) Fine aggregate In the following, “600 μm sieve residue” is the mass ratio of the remaining particles when using a 600 μm sieve (coarse particles having a particle diameter of 600 μm or more).
Silica sand A: Silica sand (water absorption rate = 1.16%, 600 μm sieve residue = 0.1% by mass, coarse particle rate = 1.27, unit volume mass = 1.54 kg / L, actual rate = 58.8% )
Silica sand B: Silica sand (water absorption rate = 1.25%, 600 μm sieve residue = 0.1 mass%, coarse grain ratio 1.15, unit volume mass = 1.53 kg / L, actual rate = 57.5%)
Silica sand C: Silica sand (water absorption rate = 3.84%, 600 μm sieve residue = 0.8 mass%, coarse particle ratio = 1.13, unit volume mass = 1.40 kg / L, actual rate = 56.8% )
Silica sand D: Silica sand (water absorption rate = 1.96%, 600 μm sieve residue = 9.0% by mass, coarse particle rate = 1.49, unit volume mass = 1.51 kg / L, actual rate = 58.7% )
Silica sand E: Silica sand (water absorption rate = 1.68%, 600 μm sieve residue = 14.2% by mass, coarse particle rate = 1.59, unit volume mass = 1.62 kg / L, actual rate = 61.9% )
Silica sand F: Silica sand (water absorption rate = 1.78%, 600 μm sieve residue = 0.1% by mass, coarse particle rate = 1.27, unit volume mass = 1.54 kg / L, actual rate = 59.6% )
3) Fluidizer: Polycarboxylic acid fluidizer (manufactured by Kao Corporation).
4) Inorganic components-Blast furnace slag fine powder (Reverment, manufactured by Chiba Rebirth Co., Ltd., Blaine specific surface area 4400 cm ² / g).
5) Setting agent:
-Bicarbonate Na: Sodium bicarbonate (made by Tosoh Corporation).
-Sodium tartrate: L-sodium tartrate (manufactured by Fuso Chemical Industries).
-Carbonic acid Li: Lithium carbonate (made by Honjo Chemical Co., Ltd.).
・ Sulfuric acid Al: anhydrous aluminum sulfate (manufactured by Daimei Chemical Industry Co., Ltd.)
6) Thickener: Hydroxyethylmethylcellulose thickener (Marporose MX-30000, manufactured by Matsumoto Yushi Co., Ltd.).
7) Antifoaming agent: Polyether type antifoaming agent (manufactured by San Nopco).

<Examples and reference examples>
Hydraulic composition obtained by kneading the hydraulic component, fine aggregate, fluidizing agent, inorganic component, setting modifier, thickener and antifoaming agent (total amount: 1.5 kg) shown in Table 1 using a chemistor. Then, 390 g of water was further added and kneaded for 3 minutes to obtain a hydraulic mortar. The hydraulic composition and the mortar were prepared in an atmosphere at a temperature of 20 ° C. and a humidity of 65%.

  Table 2 shows the results of evaluation of SL (self-leveling) characteristics, Shore hardness development, and cured body surface finish using the obtained hydraulic mortar.

  As shown in Comparative Examples 1 to 4, in the case of a hydraulic mortar using a fine aggregate with a high water absorption rate, the fluidity decreases, but the fluidity does not become constant and flows after 20 to 30 minutes have passed. There was a tendency for sex to increase. Moreover, as shown in Comparative Examples 2 and 3, when a fine aggregate having a high 600 μm sieving residue in the particle size was used, the surface accuracy after curing deteriorated.

  On the other hand, as shown in Examples 1 and 2, in the case of a self-flowing hydraulic mortar using a fine aggregate having a low water absorption rate and a low particle size residue of 600 μm, the fluidity is high and the time is long. It was kept almost constant, and the surface accuracy after curing was also good.

  From the above examples, the self-flowing hydraulic mortar using the self-flowing hydraulic composition of the present invention can stably maintain a high fluidity for a long time, so that good handling properties are obtained and the speed is further increased. It has been clarified that a cured product having a finished surface with excellent hardness and horizontal level properties and good surface accuracy can be obtained stably.

Claims (8)

A self-flowing hydraulic composition comprising a hydraulic component, fine aggregate, and a fluidizing agent,
The fine aggregate contains less than 5 mass% of coarse particles having a particle diameter of 600 μm or more in the fine aggregate (100 mass%),
A self-flowing hydraulic composition having a fine aggregate water absorption of 1.6% or less. The coarse particle ratio of the fine aggregate is in the range of 1.00 to 1.40,
The unit volume mass of the fine aggregate is in the range of 1.45 to 1.70 kg / L,
The self-flowing hydraulic composition according to claim 1, wherein the fine aggregate performance ratio is in the range of 55.0 to 61.0%.   The self-flowing hydraulic composition according to claim 1 or 2, wherein the hydraulic component (100% by mass) comprises 20 to 80% by mass of alumina cement, 5 to 70% by mass of Portland cement, and 5 to 45% by mass of gypsum.   The self-fluid hydraulic composition further includes at least one component selected from an inorganic component, a setting retarder, a resin powder, a thickener, and an antifoaming agent. Self-flowing hydraulic composition. The flow value of the self-flowing hydraulic mortar prepared by kneading the self-flowing hydraulic composition and water is in the range of 210 to 240 mm,
SL value from immediately after kneading of self-flowing hydraulic mortar to 30 minutes after kneading is in the range of 400 to 600 mm,
The SL value (L20) at the time 20 minutes after kneading and the SL value (L30) at the time 30 minutes after kneading with respect to the SL value (L0) immediately after kneading of the self-flowing hydraulic mortar, L0 = 100 The self-flowing hydraulic composition according to any one of claims 1 to 4, wherein the ratio when normalized is in the range of 100 to 120.   The shore hardness of the mortar cured body surface of the self-flowing hydraulic mortar prepared by kneading the self-flowing hydraulic composition and water is 10 or more after 3 hours from the application of the self-flowing hydraulic mortar. The self-flowing hydraulic composition according to any one of claims 1 to 5.   A self-flowing hydraulic mortar obtained by kneading the self-flowing hydraulic composition according to any one of claims 1 to 6 and water.   A concrete floor structure having a cured body layer of the self-flowing hydraulic mortar according to claim 7 as a surface layer.

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