JP5905153B1 - Hydraulic composition for centrifugal molding - Google Patents

Abstract

The present invention provides a hydraulic composition such as concrete or mortar in which a cured product exhibits sufficient strength even when the amount of a high-strength admixture is reduced to avoid the occurrence of expansion and cracking. One or more compounds selected from glycerin of component A and an ethylene oxide adduct of glycerin, one or more compounds selected from gluconic acid, tartronic acid, tartaric acid, and salts thereof of component B, A hydraulic composition for centrifugal molding, which contains naphthalene sulfonic acid formaldehyde condensate, a D component high-strength admixture, cement, water, and aggregate, and the content of components A to D in the cement is within a predetermined range. [Selection figure] None

Description

  The present invention relates to a centrifugal molding hydraulic composition and a method for producing a cured body of the hydraulic composition.

Centrifugal molding is known as a method for producing hollow cylindrical concrete molded articles such as pipes, piles and poles. This centrifugal molding method is a method in which a concrete material kneaded in a mold is put and the concrete is pressed against the inner surface of the mold by a centrifugal force generated by rotating the mold at high speed.
In Japan, when producing a concrete pile that requires high strength, a high-strength admixture is added to the concrete and steam curing is performed in order to ensure the strength that can be shipped in seven days after kneading.

Patent Document 1 describes a process for producing a centrifugal force molded body in which one or two or more selected from oxymonocarboxylic acid and a salt thereof are added in producing a molded body by centrifugal force molding. Describes that by using a high-strength admixture in combination, the centrifugal clamping state is good and high strength can be obtained.
Patent Document 2 describes a high-strength centrifugal force molding concrete composition containing early-strength Portland cement, an admixture containing anhydrous gypsum and amorphous silica under predetermined conditions, a naphthalene-based dispersant, aggregate and water. ing.

JP 59-207863 A JP 2010-1000050 A

  High-strength admixtures are effective in improving the strength of hardened concrete for centrifugal molding. However, if a large amount of high-strength admixture is used, the concrete product after curing will expand or the surface will be cracked at the manufacturing site. It turns out that there is a fear. Although it is thought that reducing the high-strength admixture leads to avoiding such problems, the strength of the hardened body of the concrete for centrifugal molding becomes insufficient. As shown in Examples of Patent Documents 1 and 2, usually, a high-strength admixture is used at an addition amount of about 10% by mass with respect to cement. It is desirable that strength can be expressed.

  The present invention provides a hydraulic composition such as concrete or mortar in which a cured product exhibits sufficient strength even when the amount of use of a high-strength admixture is reduced to avoid the occurrence of expansion and cracking.

The present invention is a hydraulic composition for centrifugal molding containing the following component A, component B, component C, component D, cement, water, and aggregate,
With respect to 100 parts by mass of cement, component A is 0.03 parts by mass or more and 0.15 parts by mass or less, component B is 0.02 parts by mass or more and 0.07 parts by mass or less, and component C is 0.5 parts by mass or more. 0 parts by mass or less, containing 0 to 8 parts by mass of D component,
The present invention relates to a hydraulic composition for centrifugal molding.
Component A: One or more compounds selected from glycerin and ethylene oxide adducts of glycerin Component B: One or more compounds selected from gluconic acid, tartronic acid, tartaric acid, and salts thereof Component C: Naphthalenesulfonic acid formaldehyde condensate D component: High-strength admixture

Moreover, this invention relates to the manufacturing method of the hardening body of the hydraulic composition including the following processes 1-5.
Step 1: A step of kneading the following A component, B component, C component, D component, cement, water, and aggregate to obtain a hydraulic composition, wherein 0 component A is added to 100 parts by mass of cement. 0.03 parts by mass to 0.15 parts by mass, B component from 0.02 parts by mass to 0.07 parts by mass, C component from 0.5 parts by mass to 1.0 part by mass, and D component from 0 parts by mass. More than 8 parts by mass of kneading step A component: glycerin and one or more compounds selected from glycerin ethylene oxide adduct B component: one or more compounds C selected from gluconic acid, tartronic acid, tartaric acid, and salts thereof Component: Naphthalenesulfonic acid formaldehyde condensate D Component: High-strength admixture Step 2: A step of filling the formwork with the hydraulic composition obtained in Step 1.
Step 3: A step of clamping the hydraulic composition filled in the mold in Step 2 by applying centrifugal force.
Step 4: A step of condensing the hydraulic composition clamped in Step 3 in a mold.
Step 5: A step of steam curing the hydraulic composition condensed in Step 4 in a mold.

  According to the present invention, there is provided a hydraulic composition such as concrete or mortar in which a cured body exhibits sufficient strength even if the amount of a high-strength admixture is reduced in order to avoid the occurrence of expansion and cracking. Can be expected to do.

Although the mechanism of action of the present invention is unclear, if the amount of high-strength admixture (component D) is reduced in order to avoid the occurrence of expansion and cracking, ettringite formation is reduced and the strength for 7 days is expected to decrease. However, since ettringite formation is supplemented by using glycerin and one or more compounds selected from ethylene oxide adducts of glycerin (component A) and a specific oxycarboxylic acid or a salt thereof (component B), the strength for 7 days It is estimated that can be secured.
The decrease in ettringite is thought to be caused by heat curing and the coexistence of calcium hydroxide crystals. The B component is presumed to suppress the reaction (abnormal hydration) of ettringite because it has the effect of refining and chelating this calcium hydroxide. In addition, it is presumed that the A component produces a large amount of ettringite by promoting the hydration of the interstitial phase at the initial stage of water contact.
It is presumed that the decrease of ettringite is suppressed by these two synergistic effects.

[Hydraulic composition for centrifugal molding]
<A component>
The component A is one or more compounds selected from glycerin and an ethylene oxide adduct of glycerin. From the viewpoint of the 7-day strength (hereinafter also referred to as 7-day strength) of the cured product of the hydraulic composition, the centrifugal molding hydraulic composition of the present invention is 0.03 mass per 100 parts by mass of cement. Part or more, preferably 0.05 part by weight or more and 0.15 part by weight or less, preferably 0.12 part by weight or less.

The average addition mole number of ethylene oxide of the glycerin ethylene oxide adduct of component A is preferably more than 0, more preferably 0.1 or more, from the viewpoint of 7-day strength. Moreover, 6 or less is preferable, 3 or less is more preferable, 2 or less is further more preferable, and 1.5 or less is still more preferable.
From the viewpoint of 7-day strength, the A component is preferably glycerin.

<B component>
The component B is one or more compounds selected from gluconic acid, tartronic acid, tartaric acid, and salts thereof. From the viewpoint of 7-day strength, the component B is preferably one or more compounds selected from tartronic acid and salts thereof. In addition, from the viewpoint of 7-day strength and availability, the component B is preferably one or more compounds selected from gluconic acid and salts thereof.
From the viewpoint of 7-day strength, the centrifugal composition for centrifugal molding of the present invention contains B component in an amount of 0.02 parts by mass or more, preferably 0.03 parts by mass or more, and 0.07 parts by mass with respect to 100 parts by mass of cement. It is contained in parts by mass or less, preferably 0.06 parts by mass or less.

<A/B mass ratio>
The mass ratio A / B between the A component and the B component is preferably 1.5 or more, more preferably 2.0 or more, and preferably 3.5 or less from the viewpoint of 7-day strength.

<C component>
Component C is a naphthalene sulfonic acid formaldehyde condensate. The C component functions as a cement dispersant. In the centrifugal molding hydraulic composition of the present invention, from the viewpoint of 7-day strength, the C component is 0.5 parts by mass or more, preferably 0.7 parts by mass or more, and 1.0 parts by mass with respect to 100 parts by mass of cement. The content is not more than part by mass, preferably not more than 0.9 part by mass.

  The weight average molecular weight of component C is preferably 1000 or more, more preferably 3000 or more, still more preferably 4000 or more, still more preferably 5000 or more, and preferably 200000 or less, more preferably 100000 or less, still more preferably 80000 or less. More preferably, it is 50000 or less. This weight average molecular weight is measured by gel permeation chromatography (GPC) shown below.

GPC conditions Column: G4000SWXL + G200SWXL (manufactured by Tosoh Corporation)
Eluent: 30 mM CH ₃ COONa / CH ₃ CN = 6/4 (pH = 6.9)
Flow rate: 1.0 mL / min
Column temperature: 40 ° C
Detection: UV (280 nm)
Sample size: 2 mg / mL, 0.01 mL
Standard material for conversion: Polystyrene sulfonic acid

  Component C can be used in liquid or powder form. Moreover, a commercial item can be used for C component, for example, Kao Co., Ltd. Mighty 150 is mentioned.

  Examples of the method for producing component C include a method of obtaining a condensate by a condensation reaction of naphthalenesulfonic acid and formaldehyde. You may neutralize the said condensate. Moreover, you may remove the water insoluble matter byproduced by neutralization. For example, the following manufacturing method is mentioned. First, in order to obtain naphthalenesulfonic acid, 1.2 to 1.4 mol of sulfuric acid is used with respect to 1 mol of naphthalene and reacted at 150 to 165 ° C. for 2 to 5 hours to obtain a sulfonated product. Next, formalin is added dropwise at 85 to 95 ° C. over 3 to 6 hours to form 0.95 to 0.99 mol as formaldehyde with respect to 1 mol of the sulfonated product, and condensed at 95 to 105 ° C. after the addition. Perform the reaction. If necessary, water and a neutralizing agent are added to the condensate, and a neutralization step is performed at 80 to 95 ° C. The neutralizing agent is preferably added in an amount of 1.0 to 1.1 moles per each of naphthalenesulfonic acid and unreacted sulfuric acid. Further, water-insoluble matter generated by neutralization may be removed, preferably separated by filtration. By these steps, an aqueous solution of a naphthalenesulfonic acid formaldehyde condensate water-soluble salt is obtained. This aqueous solution can be used as it is as a naphthalene dispersant. Further, if necessary, the aqueous solution can be dried and pulverized to obtain a powdery naphthalenesulfonic acid formaldehyde condensate water-soluble salt, which may be used as a powdery naphthalene dispersant. Drying and powdering can be performed by spray drying, drum drying, freeze drying, or the like. Although the naphthalenesulfonic acid formaldehyde condensate can be obtained by the above method, the desired product can be obtained under other conditions and methods.

<D component>
D component is a high-strength admixture.
As D component, the high intensity | strength admixture containing anhydrous gypsum is mentioned. Examples of the high-strength admixture containing anhydrous gypsum include those containing 60% by mass or more of anhydrous gypsum.
The D component has a fineness (brain specific surface area) of preferably 4000 cm ² / g or more, more preferably 5000 cm ² / g or more, preferably 15000 cm ² / g or less, more preferably 13000 cm ² / g or less. Also good.

  Commercially available products such as Denka Σ1000 manufactured by Denki Kagaku Kogyo Co., Ltd., Supermix manufactured by Taiheiyo Material Co., Ltd., Non-clave manufactured by Sumitomo Osaka Cement Co., Ltd., and Dymix manufactured by Showa KDE Co., Ltd. can be used as the high-strength admixture of D component. .

  In the centrifugal molding hydraulic composition of the present invention, the D component is preferably at least 1 part by mass, preferably at least 2 parts by mass, more preferably at least 2 parts by mass with respect to 100 parts by mass of cement, from the viewpoint of 7-day strength. Contains 3 parts by mass or more. In addition, the hydraulic composition for centrifugal molding of the present invention contains 8 parts by mass of the D component from the viewpoint of ease of molding at the time of centrifugal molding and from the viewpoint of avoiding expansion and cracking after curing of the hydraulic composition. The content is preferably 7 parts by mass or less, more preferably 5 parts by mass or less.

<Cement>
The cement used in the present invention is not particularly limited, and examples thereof include various cements such as ordinary Portland cement, early-strength Portland cement, ultra-early-strength Portland cement, mixed cement, and eco-cement (for example, JIS R5214). The hydraulic composition for centrifugal molding may include blast furnace slag, fly ash, silica fume and the like as hydraulic powder other than cement.

<Aggregate>
The hydraulic composition for centrifugal molding of the present invention contains aggregate. Examples of the aggregate include fine aggregate and coarse aggregate. The fine aggregate is preferably mountain sand, land sand, river sand and crushed sand, and the coarse aggregate is preferably mountain gravel, land gravel, river gravel and crushed stone. Depending on the application, lightweight aggregates may be used. The term “aggregate” is based on “Concrete Overview” (published on June 10, 1998, published by Technical Shoin).

<Other components and properties of centrifugal molding hydraulic composition>
The hydraulic composition for centrifugal molding of the present invention contains A component, B component, C component, D component, cement, water, and aggregate. The centrifugal molding hydraulic composition of the present invention can also contain other additives. For example, the following components can be mentioned.
-AE agent: resin soap, saturated or unsaturated fatty acid, sodium hydroxystearate, lauryl sulfate, alkylbenzene sulfonic acid or its salt, alkane sulfonate, polyoxyalkylene alkyl (phenyl) ether, polyoxyalkylene alkyl (phenyl) ether sulfate Or salt thereof, polyoxyalkylene alkyl (phenyl) ether phosphate or salt thereof, protein material, alkenyl succinic acid, α-olefin sulfonate, etc., foaming agent, thickener, silica sand, foaming agent, waterproofing material: resin acid Or its salts, fatty acid esters, oils and fats, silicone, paraffin, asphalt, wax, etc., blast furnace slag, fluidizing agents;
-Antifoaming agents: dimethylpolysiloxane, polyalkylene glycol fatty acid esters, mineral oils, fats, oxyalkylenes, alcohols, amides, etc.-Antifoaming agents / rust inhibitors: nitrites, phosphates, zinc oxide Water-soluble polymers such as: celluloses such as methyl cellulose and hydroxyethyl cellulose, natural water-soluble polymers such as β-1,3-glucan and xanthan gum, polyacrylic acid amide, polyethylene glycol, ethylene oxide adduct of oleyl alcohol or Synthetic water-soluble polymer such as a reaction product of this with vinylcyclohexene diepoxide, polymer emulsion: polymer emulsion using monomers such as alkyl (meth) acrylate

  In the hydraulic composition for centrifugal molding of the present invention, the ratio of the water content to the sum of the D component content and the cement content is (water content) / (D component content and cement content). ) × 100 (hereinafter referred to as W / P), and preferably 10% by mass or more from the viewpoint of kneadability, workability and formability of ready-mixed concrete. From the viewpoint of the effect of improving the inner surface smoothness and the end face appearance of the centrifugal molded body, W / P is preferably 50% by mass or less, more preferably 40% by mass or less, and still more preferably 35% by mass or less.

  When the hydraulic composition for centrifugal molding of the present invention contains fine aggregate (S) and coarse aggregate (G), the fine aggregate ratio (s / a) is preferably 30 volumes from the viewpoint of 7-day strength. % Or more, more preferably 35% by volume or more, and preferably 45% by volume or less, more preferably 40% by volume or less. s / a is calculated by s / a = [S / (S + G)] × 100 (volume%) based on the volume of the fine aggregate (S) and the coarse aggregate (G).

The hydraulic composition for centrifugal molding of the present invention can contain fine aggregate and coarse aggregate. In that case, the fine aggregate is contained in an amount of 450 kg or more, more preferably 550 kg or more, and preferably 950 kg or less, more preferably 750 kg or less with respect to 1 m ^{3 of} uncured concrete (fresh concrete). The coarse aggregate is contained in an amount of 1000 kg or more, more preferably 1050 kg or more, and preferably 1300 kg or less, more preferably 1200 kg or less with respect to 1 m ^{3 of} uncured concrete (fresh concrete).

  The centrifugal composition for centrifugal molding according to the present invention has a slump value of preferably 0 cm or more and 8 cm or less from the viewpoint of reducing lozenges, and improving the filling property of the hydraulic composition into the mold and reducing lozenges. Therefore, it is preferably 0.5 cm or more, more preferably 1 cm or more, and preferably 6 cm or less, more preferably 4 cm or less. The slump value is measured according to JIS A 1101.

  The hydraulic composition of the present invention can be used as concrete or mortar.

[Method for producing cured body of hydraulic composition]
The manufacturing method of the hardening body of the hydraulic composition of this invention includes the following processes 1-5.
Step 1: A step of kneading the following A component, B component, C component, D component, cement, water, and aggregate to obtain a hydraulic composition, wherein 0 component A is added to 100 parts by mass of cement. 0.03 parts by mass to 0.15 parts by mass, B component from 0.02 parts by mass to 0.07 parts by mass, C component from 0.5 parts by mass to 1.0 part by mass, and D component from 0 parts by mass. More than 8 parts by mass of kneading step A component: glycerin and one or more compounds selected from glycerin ethylene oxide adduct B component: one or more compounds C selected from gluconic acid, tartronic acid, tartaric acid, and salts thereof Component: Naphthalenesulfonic acid formaldehyde condensate D Component: High-strength admixture Step 2: A step of filling the formwork with the hydraulic composition obtained in Step 1.
Step 3: A step of clamping the hydraulic composition filled in the mold in Step 2 by applying centrifugal force.
Step 4: A step of condensing the hydraulic composition clamped in Step 3 in a mold.
Step 5: A step of steam curing the hydraulic composition condensed in Step 4 in a mold.

The manufacturing method of the hardening body of the hydraulic composition of this invention can include the following process 6 and also the process 7.
Process 6: The process of cooling a hydraulic composition after process 5 and demolding from a formwork.
Process 7: The process of curing the hardening body of the hydraulic composition obtained at the process 6 at normal temperature normal pressure.

  In step 1, the A component, the B component, the C component, and the D component may be added separately, or may be added after mixing two or more of these in advance. Moreover, when preparing a hydraulic composition, after mixing cement, D component (when using), and an aggregate, the mixture containing water, A component, B component, and C component is added and mixed. However, when manufacturing a hydraulic composition, it is preferable at the point which can mix A component, B component, C component, and D component easily and uniformly.

  As a specific method of Step 1, cement, D component (when used) and aggregate are mixed, and a mixture containing water, A component, B component and C component is made to satisfy the above quantitative relationship. The process of adding and kneading | mixing and preparing a hydraulic composition is mentioned.

The preferable aspect of A component, B component, C component, and D component used at the process 1 is the same as the preferable aspect of each component in the hydraulic composition for centrifugal molding of this invention, respectively.
The preferable ranges of the kneading amounts of the A component, the B component, the C component, and the D component with respect to the cement in the step 1 are the same as the preferable ranges of the content of each component in the centrifugal molding hydraulic composition of the present invention.
Also in step 1, the mass ratio A / B between the component A and the component B is preferably 1.5 or more, more preferably 2.0 or more, and preferably 3.5 or less from the viewpoint of 7-day strength. It is.

  In step 1, W / P is preferably 10% by mass or more from the viewpoint of kneadability, workability, and formability of ready-mixed concrete, and inner surface smoothness and end face appearance in the centrifugal molded body. From the viewpoint of the improvement effect, a hydraulic composition of preferably 50% by mass or less, more preferably 40% by mass or less, and further preferably 35% by mass or less is obtained.

  In step 2, the method of filling the mold with the hydraulic composition obtained in step 1 is a method of discharging the kneaded hydraulic composition from the kneading means and manually putting it into the mold. Can be mentioned.

  In step 3, the hydraulic composition filled in the mold is preferably clamped with a centrifugal force of 0.5 G or more. The centrifugal force of centrifugal molding is preferably 0.5 G or more and 30 G or less, more preferably 25 G or less. From the viewpoint of energy cost reduction and formability, it is preferable to maintain the centrifugal force in a range of at least 1 minute and 15 G or more, 30 G or less, and further 25 G or less.

  The compaction with a centrifugal force is, for example, 0.5 G or more and 30 G or less, preferably 5 minutes or more, more preferably 7 minutes or more, still more preferably 9 minutes or more, and preferably 40 minutes or less. From the viewpoint of compacting the molded article smoothly, compaction by holding a high centrifugal force (generally 20 G or more) is preferably 1 minute or more, more preferably 3 minutes or more, still more preferably 5 minutes or more, and preferably 10 minutes. Do the following.

  Compaction with centrifugal force can be performed in stages, and a method of increasing the centrifugal force G in stages is preferable from the viewpoint of moldability. For example, in the case of five stages, (1) the initial speed of the first stage is 0.5 G or more and less than 2 G with a centrifugal force of 1 minute or more and 10 minutes or less, and (2) the second stage of the second speed is 2 G or more and less than 5 G Centrifugal force for 1 minute or more and 10 minutes or less, (3) Third speed at the third stage is 5 G or more and less than 10 G for 1 minute or more and 10 minutes or less, and (4) Fourth stage of the fourth speed is 10 G or more and 20 G It is preferable to perform compaction at a centrifugal force of less than 1 minute to 10 minutes, and (5) the fifth stage, the fifth speed, at a centrifugal force of 20G to 30G for 1 minute to 10 minutes.

  In step 4, the hydraulic composition obtained in step 3 is condensed. Specifically, for example, a method of performing air curing for 3 to 4 hours after kneading can be mentioned.

In step 5, the hardened concrete that has entered the mold obtained in step 4 is steam-cured. As curing conditions, it is preferable to perform steam curing at 60 ° C. or more and 85 ° C. or less after performing pre-curing for 1 to 4 hours at room temperature (20 ° C.). Steps 5 and 6 can be performed continuously under a series of temperature controls.
As specific curing conditions, as step 5, the ambient temperature of the mold is raised to 60 ° C. or higher and 85 ° C. or lower at a temperature rising rate of 10 ° C. or higher and 30 ° C. or lower per hour. Hold for 8 hours or less, and then, in step 6, cool to room temperature, for example, 20 ° C., at a temperature drop rate of 5 ° C. or more and 20 ° C. or less per hour, and demold the molded body.
As an example of preferable conditions, it is allowed to stand at room temperature, for example, 20 ° C. for 3 hours, kept at a heating rate of 20 ° C./hour and at 80 ° C. for 6 hours (step 5), and then cooled to room temperature at 10 ° C./hour. Then, after 20 hours or more and 30 hours or less, the molded product is removed from the mold (step 6).
Furthermore, it is possible to perform autoclave curing at a predetermined temperature, for example, 180 ° C.

  In step 7, the cured product of the hydraulic composition obtained in step 6 is cured at normal temperature and pressure. Specifically, it is stored at 20 ° C. under atmospheric pressure.

As a method for producing a cured product of the hydraulic composition of the present invention, a cured product of a hydraulic composition in which the time from the start of the preparation of the hydraulic composition to the demolding is from 8 hours to 30 hours. The manufacturing method of these is mentioned. Here, the start of the preparation of the hydraulic composition is the time when the cement and water first contact each other.
The matters described in the centrifugal molding hydraulic composition of the present invention can be appropriately applied to the method for producing a cured product of the hydraulic composition of the present invention.

  The cured body of the hydraulic composition obtained by the production method of the present invention can be used as a centrifugal molded concrete product, and specifically includes a pile, a pole, a fume tube, and the like. The cured product of the hydraulic composition obtained by the production method of the present invention is excellent in initial strength and has a low generation amount of noro during production and can reduce waste at the production site of the product. In addition, because it is excellent in compaction, there are few irregularities on the inner surface and end surface of the product, it is excellent in surface aesthetics, and further, the inner surface of the product is finished smoothly, so that obstacles to the cutting machine during pile driving and Nakabori method are improved .

Hereinafter, embodiments of the present invention will be described.
<1>
A centrifugal composition for centrifugal molding containing the following component A, component B, component C, component D, cement, water, and aggregate,
Component A is 0.03 part by mass or more, preferably 0.05 part by mass or more and 0.15 part by mass or less, preferably 0.12 part by mass or less, and component B is 0.02 part by mass or more with respect to 100 parts by mass of cement. , Preferably 0.03 parts by mass or more and 0.07 parts by mass or less, preferably 0.06 parts by mass or less, C component 0.5 parts by mass or more, preferably 0.7 parts by mass or more and 1.0 parts by mass or less, Preferably 0.9 parts by weight or less, D component is 0 parts by weight or more, preferably 1 part by weight or more, preferably 2 parts by weight or more, more preferably 3 parts by weight or more and 8 parts by weight or less, preferably 7 parts by weight or less. More preferably 5 parts by mass or less,
A hydraulic composition for centrifugal molding.
A component: one or more compounds selected from glycerin and ethylene oxide adducts of glycerin, preferably glycerin B component: one or more compounds selected from gluconic acid, tartronic acid, tartaric acid, and salts thereof, preferably gluconic acid , Tartronic acid, and one or more compounds selected from salts thereof Component C: Naphthalenesulfonic acid formaldehyde condensate D Component: High-strength admixture

<2>
The hydraulic composition for centrifugal molding according to <1>, wherein the mass ratio A / B between the component A and the component B is 1.5 or more, preferably 2.0 or more and 3.5 or less.

<3>
The ratio of the water content to the sum of the D component content and the cement content is (water content) / (sum of the D component content and the cement content) × 100, and is 10% by mass or more. The hydraulic composition for centrifugal molding according to <1> or <2>, which is 50% by mass or less, preferably 40% by mass or less, more preferably 35% by mass or less.

<4>
One or more selected from AE agent, foaming agent, thickener, silica sand, foaming agent, waterproofing material, blast furnace slag, fluidizing agent, antifoaming agent, rust preventing agent, water-soluble polymer, and polymer emulsion The hydraulic composition for centrifugal molding according to any one of <1> to <3>, which contains an additive.

<5>
The manufacturing method of the hardening body of the hydraulic composition containing the following processes 1-5.
Step 1: A step of kneading the following A component, B component, C component, D component, cement, water, and aggregate to obtain a hydraulic composition, wherein 0 component A is added to 100 parts by mass of cement. 0.03 parts by mass or more, preferably 0.05 parts by mass or more and 0.15 parts by mass or less, preferably 0.12 parts by mass or less, and B component is 0.02 parts by mass or more, preferably 0.03 parts by mass or more and 0.0. 07 parts by mass or less, preferably 0.06 parts by mass or less, C component 0.5 parts by mass or more, preferably 0.7 parts by mass or more and 1.0 parts by mass or less, preferably 0.9 parts by mass or less, D component 0 part by mass or more, preferably 1 part by mass or more, preferably 2 parts by mass or more, more preferably 3 parts by mass or more and 8 parts by mass or less, preferably 7 parts by mass or less, more preferably 5 parts by mass or less. Ingredients: Glycerin and ethylene oxide of glycerin One or more compounds selected from id adducts, preferably glycerin B component: one or more compounds selected from gluconic acid, tartronic acid, tartaric acid, and salts thereof, preferably gluconic acid, tartronic acid, and salts thereof One or more selected compounds C component: naphthalenesulfonic acid formaldehyde condensate D component: high-strength admixture Step 2: A step of filling the formwork with the hydraulic composition obtained in Step 1.
Step 3: A step of clamping the hydraulic composition filled in the mold in Step 2 by applying centrifugal force.
Step 4: A step of condensing the hydraulic composition clamped in Step 3 in a mold.
Step 5: A step of steam curing the hydraulic composition condensed in Step 4 in a mold.

<6>
The manufacturing method of the hardening body of the hydraulic composition as described in <5> whose mass ratio A / B of A component and B component in process 1 is 1.5 or more, Preferably it is 2.0 or more and 3.5 or less.

<7>
In step 1, the ratio of the water content to the sum of the D component content and the cement content is (water content) / (sum of the D component content and the cement content) × 100. Manufacture of the hardened | cured material of the hydraulic composition as described in <5> or <6> which obtains the hydraulic composition of 10 mass% or more and 50 mass% or less, Preferably it is 40 mass% or less, More preferably, it is 35 mass% or less. Method.

<8>
The hydraulic composition according to any one of <5> to <7>, wherein the hydraulic composition filled in the mold in Step 3 is clamped with a centrifugal force of 0.5 G to 30 G, preferably 25 G or less. A method for producing a cured product.

<9>
The hydraulic composition according to <8>, wherein the hydraulic composition filled in the mold in Step 3 is clamped while holding the centrifugal force in a range of 15 G or more and 30 G or less and further 25 G or less for at least 1 minute or more. A method for producing a cured product.

<10>
In step 3, the centrifugal force is changed stepwise to clamp the hydraulic composition, and the centrifugal force is increased stepwise to clamp the hydraulic composition. (1) First step The initial speed is 0.5 G or more and less than 2 G with a centrifugal force of 1 minute or more and 10 minutes or less, (2) The second stage, the second speed is 2 G or more and less than 5 G with a centrifugal force of 1 minute or more and 10 minutes or less, (3) The third stage, the third speed, is 1 G or more and less than 10 minutes at a centrifugal force of 5 G or more and less than 10 G, and (4) the fourth stage, the fourth speed is a centrifugal force of 10 G or more and less than 20 G, for 1 minute or more and 10 minutes or less, ( 5) The hydraulic composition is clamped in five stages, in which the fifth stage, the fifth speed is a centrifugal force of 20 G or more and 30 G for 1 minute or more and 10 minutes or less, according to any one of <5> to <9> A method for producing a cured product of a hard composition.

<Example 1 and Comparative Example 1>
The following were used for A component, B component, C component, and D component. In the table, those not corresponding to the B component are also shown in the B component column for convenience.

[Component A]
Glycerin: Purified glycerin purity 99.0% or more [component B] manufactured by Kao Corporation
Sodium gluconate: Wako Pure Chemical Industries, Ltd. First grade purity 98% or higher Tartronic acid: SIGMA, Aldrich, purity 99% or higher Tartaric acid: Wako Pure Chemical Industries, Ltd. Special grade purity 99% or higher [Comparative oxycarboxylic acid]
Citric acid: Wako Pure Chemical Industries, Ltd., purity 99.5% or higher Malonic acid: SIGMA, Aldrich, purity 99% or higher [C component]
Naphthalenesulfonic acid formaldehyde condensate (indicated in the table as NSF): weight average molecular weight 20,000, manufactured by Kao Corporation, Mighty 150. The weight average molecular weight was measured by GPC under the above conditions.

[D component]
High-strength admixture: D1: Taiheiyo Material Co., Ltd. Supermix (containing 60% by mass or more of anhydrous gypsum)
High-strength admixture: D2: Denka Σ1000 (containing 60% by mass or more of anhydrous gypsum) manufactured by Denki Kagaku Kogyo Co., Ltd.

Contains mortar

The components in Table 1 are as follows. The D component is as described above.
W: Wakayama City tap water C: Ordinary Portland cement: Ordinary Portland cement manufactured by Taiheiyo Cement Co., Ltd./Sumitomo Osaka Cement Co., Ltd. Normal Portland cement = 1/1 (mass ratio) mixed cement S: Fine aggregate: Joyo Mountain sand W / P indicates mass% of (content of W) / (total of content of C and content of D component) × 100 (hereinafter the same).

Production of mortar Mortar was produced under the blending conditions shown in Table 1. Specifically, using a mortar mixer (all-purpose mixing stirrer manufactured by Dalton Co., Ltd. model: 5DM-03-γ), D component, cement (C) and fine aggregate (S) were added and kneaded for 30 seconds. Add kneading water (W1), knead for 60 seconds at low speed rotation, add kneading water (W2) containing A, B, and C components, then knead for 240 seconds at low speed rotation and centrifuge forming A mortar was prepared. The total of the amount of W1 and the amount of W2 is the amount of W in Table 1. Moreover, the amount of A component, B component, and C component was included in the amount of W2. The mass ratio of the amount of W1 and the amount of W2 was 70:30 with W1: W2.
In addition, Table 2 shows the effective amount (parts by mass) of A component, B component, C component, and D component added to 100 parts by mass of cement.
A cured product can be produced by performing Steps 2 to 5 of the present invention, and further Steps 6 and 7 using the obtained mortar for centrifugal molding.

Compressive strength According to JIS A1132, a mortar was filled into a mold of a cylindrical plastic mold (bottom diameter: 5 cm, height 10 cm) by a two-layer filling method. After pre-setting at 20 ° C. for 3 hours, the temperature was raised to 70 ° C. at a rate of 20 ° C./hour, and kept at 70 ° C. for 4 hours for steam curing. Thereafter, it was naturally cooled to room temperature and cured in the air to obtain a cured mortar. Then, after 7 days, for each cured body, the compressive stress of the cured body was measured based on JIS A1108 to determine the compressive strength. These results are shown in Table 2. The compressive strength obtained here correlates with the compressive strength of the cured product obtained by centrifugal molding.

* 1 parts by mass with respect to 100 parts by mass of cement

  From the results of Table 2, it can be seen that the concrete of the examples using the A component, the B component, the C component, and the D component has improved compressive strength after 7 days as compared with the concrete of the comparative example. Normally, about 10 parts by mass of D component is used with respect to 100 parts by mass of cement. In this test, the amount of D component added is reduced to 4 parts by mass with respect to 100 parts by mass of cement. The strength of the concrete is sufficient for shipping.

<Example 2 and Comparative Example 2>
Mortar blending was as shown in Table 3 below, and addition amounts of components A to D were as shown in Table 4, mortars were produced in the same manner as in Example 1 and Comparative Example 1, and compressive strength was measured. The results are shown in Table 4. The components in Tables 3 and 4 are the same as those in Example 1 and Comparative Example 1.

* 1 parts by mass with respect to 100 parts by mass of cement

<Example 3 and Comparative Example 3>
Concrete mix

Manufacture of concrete Concrete was manufactured under the blending conditions shown in Table 5. Specifically, components A and B, C component, and D component of the types and amounts shown in Table 6 were added and kneaded for 4 minutes with a forced biaxial mixer to prepare centrifugal molding concrete.
Table 6 shows the effective amount (parts by mass) of the A component, the B component, the C component, and the D component with respect to 100 parts by mass of cement. The components in Tables 5 and 6 are the same as those in Example 1 and Comparative Example 1. In Table 5, G is coarse aggregate, and crushed stone and small (1505) were used.

Compressive strength The compression area was calculated from the average thickness of the cured product. About the hardening body which measured thickness, the compressive stress 7 days after kneading | mixing was measured according to JISA1108. The compressive strength was determined by the formula of compressive strength = compressive stress / compressed area.

Formability Put concrete for centrifugal molding in a centrifugal mold (inner diameter 20cm x height 30cm), initial speed is 0.7G for 3 minutes, second speed is 5G for 4 minutes, third speed is 15G for 2 minutes, fourth speed Was centrifuged at 25G for 3 minutes. Then, after pre-positioning at 20 ° C. for 3 hours, the temperature was raised to 80 ° C. at a rate of 18 ° C./hour, and steam curing was performed at 80 ° C. for 8 hours. Thereafter, it was naturally cooled to room temperature and cured in the air to obtain a hardened concrete. After demolding, the concrete thickness (mm) of the upper and lower parts of the cured body was measured at four locations (total of 8 locations) and evaluated according to the following criteria.
A: The difference between the maximum value and the minimum value of the thickness at 8 locations is less than 3 mm. ○: The difference between the maximum value and the minimum value of the thickness at 8 locations is 3 mm or more and less than 5 mm. State)
Δ: The difference between the maximum value and the minimum value of the thickness at 8 locations is 5 mm or more and less than 7 mm. ×: The difference between the maximum value and the minimum value of the thickness at 8 locations is 7 mm or more. State)
The smaller the difference between the maximum value and the minimum value of thickness, the more uniform is formed, and the more excellent the formability.

* 1 parts by mass with respect to 100 parts by mass of cement

Claims (6)

A centrifugal composition for centrifugal molding containing the following component A, component B, component C, component D, cement, water, and aggregate,
With respect to 100 parts by mass of cement, component A is 0.03 parts by mass or more and 0.15 parts by mass or less, component B is 0.02 parts by mass or more and 0.07 parts by mass or less, and component C is 0.5 parts by mass or more. 0 parts by mass or less, containing 0 to 8 parts by mass of D component,
A hydraulic composition for centrifugal molding.
Component A: One or more compounds selected from glycerin and ethylene oxide adducts of glycerin Component B: One or more compounds selected from gluconic acid, tartronic acid, tartaric acid, and salts thereof Component C: Naphthalenesulfonic acid formaldehyde condensate D component: High-strength admixture   The hydraulic composition for centrifugal molding according to claim 1, wherein the mass ratio A / B of the A component and the B component is 1.5 or more and 3.5 or less.   The ratio of the water content to the sum of the D component content and the cement content is (water content) / (sum of the D component content and the cement content) × 100, and is 10% by mass or more. The hydraulic composition for centrifugal molding according to claim 1 or 2, wherein the hydraulic composition is 50% by mass or less. The manufacturing method of the hardening body of the hydraulic composition containing the following processes 1-5.
Step 1: A step of kneading the following A component, B component, C component, D component, cement, water, and aggregate to obtain a hydraulic composition, wherein 0 component A is added to 100 parts by mass of cement. 0.03 parts by mass to 0.15 parts by mass, B component from 0.02 parts by mass to 0.07 parts by mass, C component from 0.5 parts by mass to 1.0 part by mass, and D component from 0 parts by mass. More than 8 parts by mass of kneading step A component: glycerin and one or more compounds selected from glycerin ethylene oxide adduct B component: one or more compounds C selected from gluconic acid, tartronic acid, tartaric acid, and salts thereof Component: Naphthalenesulfonic acid formaldehyde condensate D Component: High-strength admixture Step 2: A step of filling the formwork with the hydraulic composition obtained in Step 1.
Step 3: A step of clamping the hydraulic composition filled in the mold in Step 2 by applying centrifugal force.
Step 4: A step of condensing the hydraulic composition clamped in Step 3 in a mold.
Step 5: A step of steam curing the hydraulic composition condensed in Step 4 in a mold.   The manufacturing method of the hardening body of the hydraulic composition of Claim 4 whose mass ratio A / B of A component and B component in process 1 is 1.5 or more and 3.5 or less.   In step 1, the ratio of the water content to the sum of the D component content and the cement content is (water content) / (sum of the D component content and the cement content) × 100. The manufacturing method of the hardening body of the hydraulic composition of Claim 4 or 5 which obtains a hydraulic composition of 10 mass% or more and 50 mass% or less.