Hydraulic composition

Abstract

To provide a hydraulic composition including a polycarboxylic acid-based dispersant, wherein the hydraulic composition has a good fluidity which is difficult to be influenced by temperature in an extended period (between initially after kneading to 4 hours thereafter) and excellent high-early-strength property (after kneading to 24 hours).SOLUTION: A hydraulic composition includes the following (a) component, (b) component, (c) component, a hydraulic powder, water, and an aggregate, wherein the (a) component is a copolymer which is a copolymer including a monomer (1a) represented by a general formula (1a) and a monomer (2a) represented by a general formula (2a) as constituting monomers, with an average ratio of the monomer (2a) in all the constituent monomers being 60 mol% or over and 88 mol% or under; the (b) component is a thickener; and the (c) component is an oxycarboxylic acid or a salt thereof.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a hydraulic composition. [Background technology]

[0002] There are some fields where anti-segregation underwater is required when pouring concrete. For example, Patent Document 1 discloses that, since water may come into contact with concrete due to spring water during tunnel excavation, it is desirable for concrete used in tunnel construction methods such as the SENS method to have excellent anti-separation properties underwater, and further, since temperature conditions during tunnel construction vary depending on the environment, it is desirable for anti-separation properties underwater to have low temperature dependency. In order to meet these requirements, Patent Document 1 discloses a hydraulic composition that contains two or more specific amine oxide compounds, hydraulic powder, water, aggregate, and a polycarboxylic acid dispersant, and has a water / hydraulic powder ratio of 30% or more and 60% or less. Patent Document 2 discloses a hydraulic composition that is difficult to be washed away even with running water, has reliable non-separation properties in water, can be applied underwater, and allows adjustment of the time it takes for fluidity to disappear (gel time), and the hydraulic composition contains a cationic surfactant, an anionic aromatic compound, a hydraulic powder, a quick-setting agent, gluconic acid and / or a salt thereof, and water. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2021-172530 A [Patent Document 2] JP 2008-137852 A Summary of the Invention [Problem to be solved by the invention]

[0004] At the construction site of the hydraulic composition, depending on the progress of casting, long-term fluidity retention and removal from the formwork the next day from the viewpoint of construction time may be required. Furthermore, the outside temperature changes daily at the construction site. As a result, in order to achieve long-term fluidity retention and early hardening of the hydraulic composition at the site regardless of the outside temperature, an agent that is easy to handle and does not change in amount to be used is required. However, when a polycarboxylic acid dispersant is used as the agent, the amount of the polycarboxylic acid dispersant adsorbed to the hydraulic powder contained in the hydraulic composition changes due to changes in the outside temperature, so that the fluidity of the hydraulic composition changes. As a result, it is necessary to change the amount of the polycarboxylic acid dispersant used to control the fluidity each time, which leads to difficulty in handling at the construction site. Therefore, a polycarboxylic acid dispersant that is not easily affected by the outside temperature is desired. Therefore, the inventors considered that by investigating a polycarboxylic acid-based dispersant that exhibits little change in the amount of adsorption even when the outside temperature changes, it would become unnecessary to change the amount used each time the outside temperature changes, leading to easier handling at the construction site. Patent Document 1 discloses a hydraulic composition that is excellent in anti-separation property in water and is not easily affected by temperature, but does not mention anything about the long-term fluidity retention or early hardening of the hydraulic composition. Moreover, Patent Document 2 does not mention anything about the influence of temperature on the hydraulic composition.

[0005] The present invention provides a hydraulic composition containing a polycarboxylic acid-based dispersant, which has good fluidity for a long time (from immediately after mixing to 4 hours) that is not easily affected by temperature, and has excellent early hardening property (24 hours after mixing). [Means for solving the problem]

[0006] The present invention relates to a hydraulic composition containing the following components (a), (b), and (c), hydraulic powder, water, and aggregate. Component (a): a copolymer comprising, as constituent monomers, a monomer (1a) represented by the following general formula (1a) and a monomer (2a) represented by the following general formula (2a), in which the average proportion of the monomer (2a) in all constituent monomers is 60 mol % or more and 88 mol % or less. (b) Ingredient: Thickener (c) Component: oxycarboxylic acid or its salt

[0007] [ka]

[0008] [During the ceremony, R 1a , R 2a : may be the same or different, hydrogen atom or methyl group R 3a : Hydrogen atom or -COO(AO) n1 X 1 R 4a : Hydrogen atom or an alkyl group having 1 to 4 carbon atoms AO: a group selected from an ethyleneoxy group and a propyleneoxy group n1: the average number of moles of AO added, a number between 20 and 130 q1: A number between 0 and 2 p1: 0 or 1 Indicates the following.

[0009] [ka]

[0010] [During the ceremony, R 5a , R 6a , R 7a may be the same or different, and may be a hydrogen atom, a methyl group or (CH2) r COOM 2 and (CH2) r COOM 2 COOM 1 or other (CH2) r COOM 2 and an anhydride may be formed, in which case, M 1 , M 2 does not exist. M 1 , M 2may be the same or different, and are a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group, or an alkenyl group. r: A number between 0 and 2 Indicates the following. Effect of the Invention

[0011] According to the present invention, there is provided a hydraulic composition containing a polycarboxylic acid-based dispersant, which has good fluidity over a long period of time (from immediately after mixing to 4 hours) that is not easily affected by temperature (temperature versatility of fluidity) and has excellent early hardening properties (24 hours after mixing). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The present inventors have found that when a hydraulic composition contains a specific polycarboxylic acid dispersant, component (a), the above-mentioned component (b), and the above-mentioned component (c), the composition has good long-term (4 hours from immediately after mixing) fluidity that is not easily affected by temperature, and has excellent early hardening properties (24 hours from mixing). The reason why such effects are exhibited is not entirely clear, but is presumed to be as follows. When the components (a), (b), and (c) of the present invention are contained in a hydraulic composition, it is considered that the components (a) and (c) are competitively adsorbed to the hydraulic powder, and the component (c) is preferentially adsorbed because of its small molecular weight, and the component (a) remains in the bulk phase. The component (b) thickens the hydraulic composition, and it is considered that the component (a) is adsorbed over a long period of time (from immediately after mixing to 4 hours) by slowing down the adsorption rate of the component (a) remaining in the bulk phase to the hydraulic powder, and thus the component (a) is adsorbed over a long period of time (from immediately after mixing to 4 hours), and thus the fluidity is maintained for a long time. Furthermore, since the adsorption amount of the component (a) varies little depending on the temperature, it is presumed that the fluidity for a long period of time is not affected by the temperature, and after a long period of storage, the component (a) remaining in the bulk phase is gradually consumed, which reduces the fluidity and promotes the hydration reaction, resulting in excellent early strength of the hydraulic composition hardened body after, for example, 24 hours. In other words, it is presumed that the problems of the present invention can be solved by combining components (a), (b), and (c) of the present invention.

[0013] [Hydraulic composition] <Component (a)> The component (a) of the present invention is a copolymer containing, as constituent monomers, a monomer (1a) represented by the following general formula (1a) and a monomer (2a) represented by the following general formula (2a), in which the average proportion of the monomer (2a) in all the constituent monomers is 60 mol % or more and 88 mol % or less. In the present invention, when one copolymer containing monomer (1a) and monomer (2a) as constituent monomers is used as component (a), the average proportion of monomer (2a) in all constituent monomers in this copolymer is taken as the average proportion of monomer (2a). When two or more copolymers containing monomer (1a) and monomer (2a) as constituent monomers are used as component (a), the average proportion of monomer (2a) is calculated by the average proportion of monomer (2a) in all constituent monomers in the entire copolymer from the proportion (mol %) of monomer (2a) in all constituent monomers in each copolymer and the proportion (mass %) of each copolymer in component (a).

[0014] [ka]

[0015] [During the ceremony, R 1a , R 2a : may be the same or different, hydrogen atom or methyl group R 3a : Hydrogen atom or -COO(AO) n1 X 1 R 4a : Hydrogen atom or an alkyl group having 1 to 4 carbon atoms AO: a group selected from an ethyleneoxy group and a propyleneoxy group n1: the average number of moles of AO added, a number between 20 and 130 q1: A number between 0 and 2 p1: 0 or 1 Indicates the following.

[0016] [ka]

[0017] [During the ceremony, R 5a , R 6a , R 7a may be the same or different, and may be a hydrogen atom, a methyl group or (CH2) r COOM 2 and (CH2) r COOM 2 COOM 1 or other (CH2) r COOM 2 and an anhydride may be formed, in which case, M 1 , M 2 does not exist. M 1 , M 2 may be the same or different, and are a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group, or an alkenyl group. r: A number between 0 and 2 Indicates the following.

[0018] In general formula (1a), R 1a is preferably a hydrogen atom from the viewpoint of temperature versatility of fluidity in the hydraulic composition. In general formula (1a), R 2a From the viewpoint of temperature versatility of fluidity in the hydraulic composition, a methyl group is preferred. In general formula (1a), R 3a is preferably a hydrogen atom from the viewpoint of temperature versatility of fluidity in the hydraulic composition. In general formula (1a), R 4a From the viewpoint of temperature versatility of fluidity in the hydraulic composition, is preferably a hydrogen atom or a methyl group, and more preferably a methyl group. In the general formula (1a), AO is preferably an ethyleneoxy group from the viewpoint of temperature versatility of fluidity in the hydraulic composition. AO preferably contains an ethyleneoxy group. In the general formula (1a), n1 is the average number of moles of AO added, and from the viewpoint of the early strength of the hydraulic composition, it is 20 or more, preferably 40 or more, more preferably 50 or more, even more preferably 60 or more, still more preferably 80 or more, still more preferably 100 or more, and is 130 or less, preferably 125 or less, more preferably 120 or less. In the general formula (1a), q1 is preferably 0 from the viewpoint of temperature versatility of fluidity in the hydraulic composition. In the general formula (1a), p1 is preferably 1 from the viewpoint of the temperature versatility of fluidity in the hydraulic composition.

[0019] In producing the monomer (1a), sulfonic acid may be used as an acid catalyst. For example, such a method is described in JP 2008-214638 A. In producing the component (a) of the present invention, a mixture containing the monomer (1a) and sulfonic acid produced by such a method can be used as it is, as long as it does not impair the effects of the present invention.

[0020] In the general formula (2a), from the viewpoint of temperature versatility of fluidity in the hydraulic composition, R 5a is preferably a hydrogen atom. In the general formula (2a), from the viewpoint of temperature versatility of fluidity in the hydraulic composition, R 6a is preferably a methyl group. In the general formula (2a), from the viewpoint of temperature versatility of fluidity in the hydraulic composition, R 7a is preferably a hydrogen atom. (CH2) r COOM 2 About COOM 1 or other (CH2) r COOM 2 and an anhydride may be formed, in which case, M 1 , M 2 does not exist. M 1 and M. 2may be the same or different and are a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group, or an alkenyl group. M 1 , M 2 The alkyl group, the hydroalkyl group, and the alkenyl group each preferably have 1 to 4 carbon atoms. M 1 and M. 2 may be the same or different and are preferably a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, or an alkylammonium group, more preferably a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), or an ammonium group, even more preferably a hydrogen atom, an alkali metal, or an alkaline earth metal (1 / 2 atom), and even more preferably a hydrogen atom or an alkali metal. From the viewpoint of temperature versatility of fluidity in a hydraulic composition, (CH2) in general formula (2a) r COOM 2 In the formula, r is preferably 0.

[0021] The average proportion of the monomer (2a) in all the constituent monomers of the component (a) is, from the viewpoint of temperature versatility of fluidity in the hydraulic composition, 60 mol % or more, preferably 65 mol % or more, more preferably 70 mol % or more, even more preferably 75 mol % or more, and 88 mol % or less, preferably 85 mol % or less, more preferably 83 mol % or less.

[0022] The average proportion of monomer (1a) in all constituent monomers of component (a) is, from the viewpoint of temperature versatility of fluidity in the hydraulic composition, preferably 12 mol % or more, more preferably 15 mol % or more, even more preferably 17 mol % or more, and preferably 40 mol % or less, more preferably 35 mol % or less, even more preferably 30 mol % or less, and further more preferably 25 mol % or less. In the present invention, when one copolymer containing monomer (1a) and monomer (2a) as constituent monomers is used as component (a), the average proportion of monomer (1a) in all constituent monomers in this copolymer is taken as the average proportion of monomer (1a). When two or more copolymers containing monomer (1a) and monomer (2a) as constituent monomers are used as component (a), the average proportion of monomer (1a) is calculated by the average proportion of monomer (1a) in all constituent monomers in the entire copolymer from the proportion (mol %) of monomer (1a) in all constituent monomers in each copolymer and the proportion (mass %) of each copolymer in component (a).

[0023] In the total constituent monomers of the component (a), the average total proportion of the monomer (1a) and the monomer (2a) is preferably 80 mol% or more, more preferably 90 mol% or more, even more preferably 95 mol% or more, and preferably 100 mol% or less, from the viewpoint of temperature versatility of fluidity in the hydraulic composition. This average total amount may be 100 mol%. In the present invention, the average total proportion of monomer (1a) and monomer (2a) in all constituent monomers of component (a) is defined as follows: when one copolymer containing monomer (1a) and monomer (2a) as constituent monomers is used as component (a), the total proportion (mol %) of monomer (1a) and monomer (2a) in all constituent monomers of this copolymer is defined as the average total proportion of monomer (1a) and monomer (2a); When two or more copolymers containing (1a) and monomer (2a) as constituent monomers are used, the average of the total proportions of monomer (1a) and monomer (2a) in all constituent monomers in all copolymers is calculated from the total proportion (mol %) of monomer (1a) and monomer (2a) in all constituent monomers in each copolymer and the proportion (mass %) of each copolymer in component (a), and this is used as the average total proportion of monomer (1a) and monomer (2a).

[0024] From the viewpoint of temperature versatility of fluidity in the hydraulic composition, the weight average molecular weight of component (a) is preferably 15,000 or more, more preferably 25,000 or more, even more preferably 350,000 or more, and preferably 100,000 or less, more preferably 80,000 or less, even more preferably 60,000 or less. When component (a) contains two or more types of copolymers containing monomer (1a) and monomer (2a) as constituent monomers, it is preferable that the weight average molecular weight of at least one of the copolymers is within the above range.

[0025] The weight average molecular weight of the component (a) was measured by gel permeation chromatography (GPC) under the following conditions. *GPC conditions Equipment: GPC (HLC-8320GPC) manufactured by Tosoh Corporation Column: G4000PWXL+G2500PWXL (Tosoh Corporation) Eluent: 0.2M phosphate buffer / CH3CN=9 / 1 Flow rate: 1.0mL / min Column temperature: 40℃ Detection: RI Sample size: 0.2mg / mL Standard substance: Polyethylene glycol equivalent (monodisperse polyethylene glycol with known molecular weight, molecular weight 87,500, 250,000, 145,000, 46,000, 24,000)

[0026] From the viewpoint of the temperature versatility of fluidity in the hydraulic composition, the component (a) preferably contains two or more types of copolymers containing the monomer (1a) and the monomer (2a) as constituent monomers, and more preferably contains (a1) a copolymer containing the monomer (1a) and the monomer (2a) as constituent monomers, in which the proportion of the monomer (2a) in all constituent monomers is 70 mol % or more and 85 mol % or less (hereinafter referred to as the component (a1)), and (a2) a copolymer containing the monomer (1a) and the monomer (2a) as constituent monomers, in which the proportion of the monomer (2a) in all constituent monomers is less than 70 mol % or more than 85 mol % (hereinafter referred to as the component (a2)).

[0027] <(b) Component> The component (b) of the present invention is a thickener. From the viewpoints of preventing separation underwater in the hydraulic composition and controlling the rate at which the component (a) is adsorbed onto the hydraulic powder, the component (b) is preferably a combination of (b1) an amine oxide surfactant (hereinafter referred to as component (b11)) and an anionic aromatic compound (hereinafter referred to as component (b12)) (hereinafter referred to as component (b1)), or (b2) a cellulose-based thickener (hereinafter referred to as component (b2)).

[0028] As the amine oxide surfactant of the component (b11), a compound represented by the following general formula (b11) is preferable.

[0029] [ka]

[0030] [Wherein, X is R 11b or R 12b -[CONH-CH2CH2CH2] n R is a group represented by the formula: 11b R is an alkyl group having 14 to 22 carbon atoms or an alkenyl group having 14 to 22 carbon atoms. 12b is an alkyl group having 13 to 21 carbon atoms or an alkenyl group having 13 to 21 carbon atoms. n is an integer of 1 to 3. 2 and R 3 are each independently an alkyl group having 1 to 4 carbon atoms or -(C2H4O) p H. p is the average number of moles added, and R 2 and R 3 The sum of these is a number between 0 and 5.

[0031] In the general formula (b11), X is R 11b or R 12b -[CONH-CH2CH2CH2] n - is a group represented by the formula: R 11b is an alkyl group having 14 to 22 carbon atoms or an alkenyl group having 14 to 22 carbon atoms. R 11b When is an alkenyl group, it preferably has 18 or more carbon atoms and preferably has 22 or less carbon atoms. R 11b When is an alkyl group, it preferably has 16 or more carbon atoms and preferably has 22 or less carbon atoms. R 12b is an alkyl group having 13 to 21 carbon atoms or an alkenyl group having 13 to 21 carbon atoms. R 12b When is an alkenyl group, it preferably has 17 or more carbon atoms and preferably has 21 or less carbon atoms. R 12b When it is an alkyl group, it preferably has 15 or more carbon atoms and preferably has 21 or less carbon atoms. n is preferably 0 or 1. R 2 and R 3 are each independently preferably an alkyl group having 1 to 2 carbon atoms or -(C2H4O) p It is a group represented by H. p is preferably a number between 0 and 3.

[0032] From the viewpoint of the non-separation property in the hydraulic composition under water and the control of the adsorption rate of the component (a) to the hydraulic powder, the hydraulic composition of the present invention preferably contains, as the component (b11), two or more compounds represented by the general formula (b11) [hereinafter, also referred to as compound (b11)]. The two or more compounds have different X in the general formula (b11), and at least one of the two or more compounds has R of X in the general formula (b11). 11b or R 12b is an alkenyl group compound.

[0033] Regarding the compound (b11), when X in the general formula (b11) is different, for example, when the compound (b11) is of two types, the following embodiments can be mentioned. In the following embodiments, R 11b or R 12b is an alkenyl group. (i) One R 11b or R 12b is an alkyl group, and the other R 11b or R 12b is an alkenyl group. (ii) One R 11b or R 12b The number of carbon atoms in the other R 11b or R 12b The carbon numbers are different. (iii) One X is R 11b and the other X is R 12b -[CONH-CH2CH2CH2] n -It is. (iv) X is R 12b -[CONH-CH2CH2CH2] n - and one n is different from the other n. (v) A combination of (i) to (iv) above.

[0034] The hydraulic composition of the present invention contains, as the component (b1), two or more, preferably five or less, more preferably two, compounds (b11) in which X in the general formula (b11) is different. At least one of the two or more compounds (b11) contained in the hydraulic composition is R of X in the general formula (b11). 11b or R 12b is an alkenyl group having 14 to 22 carbon atoms, that is, R 11b R is an alkenyl group having 14 to 22 carbon atoms; 12b It is a compound containing an alkenyl group having 13 to 21 carbon atoms as the alkyl group.

[0035] In the present invention, there are two types of compound (b11), and one of the two types of compound (b11), including the above (i) to (v), is a compound in which X in the general formula (b11) is R 11b and an alkenyl group having 14 to 22 carbon atoms. That is, the hydraulic composition of the present invention contains, as the component (b1), two types of compounds represented by the general formula (b11), and the two types of compounds have different X in the general formula (b11), and one of the two types of compounds has X in the general formula (b11) represented by R 11band R 11b is an alkenyl group.

[0036] The hydraulic composition of the present invention has, as the component (b1), 11b or R 12b -[CONH-CH2CH2CH2] n - (wherein R 11b is an alkenyl group having 14 to 22 carbon atoms, R 12b is an alkenyl group having 13 to 21 carbon atoms), and a compound (b11-2) in which X in general formula (b11) is different from that of compound (b11-1). Specifically, the component (b1) may be a hydraulic composition containing a compound (b11-1) represented by the following general formula (b11-1) and a compound (b11-2) represented by the following general formula (b11-2).

[0037] [ka]

[0038] [During the ceremony, n1 and n2 each independently represent an integer of 0 to 3. R 13b When n1 is 0, it is an alkenyl group having 14 to 22 carbon atoms, and when n1 is 1 to 3, it is an alkenyl group having 13 to 21 carbon atoms. R 14b When n2 is 0, it is an alkyl group having 14 to 22 carbon atoms or an alkenyl group having 14 to 22 carbon atoms, and when n2 is 1 to 3, it is an alkyl group having 13 to 21 carbon atoms or an alkenyl group having 13 to 21 carbon atoms. However, if n1 and n2 are the same number, R 11b The alkenyl group in R 11a is an alkenyl group different from R 2 and R 3 are each independently an alkyl group having 1 to 4 carbon atoms or -(C2H4O)p H. p is the average number of moles added, and R 2 and R 3 The sum of these is a number between 0 and 5.

[0039] In general formula (b11-1), R 13b The number of carbon atoms is preferably 17 or more and preferably 22 or less. In general formula (b11-1), n1 is preferably 0 or 1, and more preferably 0.

[0040] In general formula (b11-2), n2 is 0 and R 14b When is an alkyl group, R 14b The number of carbon atoms is preferably 16 or more and preferably 22 or less. In general formula (b11-2), n2 is 0 and R 14b When is an alkenyl group, R 14b The number of carbon atoms is preferably 18 or more and preferably 22 or less. In general formula (b11-2), n2 is 1 to 3 and R 14b When is an alkyl group, R 14b The number of carbon atoms is preferably 15 or more and preferably 21 or less. In general formula (b11-2), n2 is 1 to 3 and R 14b When is an alkenyl group, R 14b The number of carbon atoms is preferably 17 or more and preferably 21 or less. In general formula (b11-2), R 14b is preferably an alkyl group. In general formula (b11-2), n2 is preferably 0 or 1.

[0041] In formula (b11-1) or (b11-2), R 2 and R 3 are each independently preferably an alkyl group having 1 or 2 carbon atoms or -(C2H4O) p H, and more preferably an alkyl group having 1 or 2 carbon atoms. In formula (b11-1) or (b11-2), p is preferably a number of 0 or more and 3 or less. If n1 and n2 are the same number, R 14b The alkenyl group in R 13b is an alkenyl group different from

[0042] The hydraulic composition of the present invention may, as the component (b1), contain a compound (b11-3) represented by the following general formula (b11-3) and a compound (b11-2) represented by the following general formula (b11-2).

[0043] [ka]

[0044] [During the ceremony, n2 is an integer between 0 and 3. R 13b is an alkenyl group having 14 to 22 carbon atoms. R 14b When n2 is 0, it is an alkyl group having 14 to 22 carbon atoms or an alkenyl group having 14 to 22 carbon atoms, and when n2 is 1 to 3, it is an alkyl group having 13 to 21 carbon atoms or an alkenyl group having 13 to 21 carbon atoms. However, if n1 and n2 are the same number, R 14b The alkenyl group in R 13b is an alkenyl group different from R 2 and R 3 are each independently an alkyl group having 1 to 4 carbon atoms or -(C2H4O) p H. p is the average number of moles added, and R 2 and R 3 The sum of these is a number between 0 and 5.

[0045] The compound (b11-3) represented by the general formula (b11-3) corresponds to the compound in which n1 is 0 in the general formula (b11-1). 13b , R 2 and R 3The preferred embodiments of the compound (b11-2) in this combination are the same as those in the general formula (b11-1).

[0046] The component (b12) is an anionic aromatic compound. The anionic aromatic compound may be one or more compounds selected from sulfonic acid having an aromatic ring, carboxylic acid having an aromatic ring, phosphonic acid having an aromatic ring, or salts thereof, and is preferably one or more compounds selected from sulfonic acid having an aromatic ring, carboxylic acid having an aromatic ring, or salts thereof. The anionic aromatic compound is preferably an acid type compound having a total carbon number of 6 or more and 12 or less. Specific examples of the anionic aromatic compound include one or more selected from salicylic acid, p-toluenesulfonic acid, sulfosalicylic acid, benzoic acid, m-sulfobenzoic acid, p-sulfobenzoic acid, 4-sulfophthalic acid, 5-sulfoisophthalic acid, p-phenolsulfonic acid, m-xylene-4-sulfonic acid, cumenesulfonic acid, methylsalicylic acid, styrenesulfonic acid, chlorobenzoic acid, and salts thereof. From the viewpoint of non-separation in water in the hydraulic composition and control of the adsorption rate of the component (a) to the hydraulic powder, one or more selected from m-xylene-4-sulfonic acid, cumenesulfonic acid, methylsalicylic acid, styrenesulfonic acid, and salts thereof are preferred, one or more selected from m-xylene-4-sulfonic acid, cumenesulfonic acid, and salts thereof are more preferred, and m-xylene-4-sulfonic acid or a salt thereof is even more preferred.

[0047] The component (b2) is a cellulose-based thickener. Examples of the cellulose-based thickener include hydroxypropylmethylcellulose, hydroxyethylcellulose, and methylcellulose. The cellulose-based thickener is preferably a cellulose-based thickener selected from hydroxypropylmethylcellulose and methylcellulose. The cellulose-based thickener is preferably a cellulose cellulose. It is also possible to use cellulose in the form of fiber, cellulose nanofiber, or cellulose nanocrystal.

[0048] The cellulose-based thickener preferably has a structure in which the hydroxyl groups of the glucose ring of cellulose are substituted with methoxy groups. In this case, the degree of substitution of the cellulose-based thickener, defined as the average number of hydroxyl groups substituted with methoxy groups per glucose ring unit of cellulose, is preferably 5 or less, more preferably 4 or less, even more preferably 3 or less, and even more preferably 2 or less, and is preferably 0.01 or more, more preferably 0.1 or more, even more preferably 0.5 or more, and even more preferably 1.0 or more, from the viewpoint of non-separation in water in the hydraulic composition and control of the adsorption rate of the component (a) to the hydraulic powder.

[0049] Also, the cellulose-based thickener is preferably one having a structure in which the hydroxyl group of the glucose ring of cellulose is replaced with a hydroxypropoxy group or a hydroxyethoxy group, such as hydroxypropylmethylcellulose or hydroxyethylcellulose. In this case, from the viewpoint of the non-separation property in water in the hydraulic composition and the control of the adsorption rate to the hydraulic powder of the component (a), the cellulose-based thickener has a substitution molar number defined as the average molar number of hydroxypropoxy groups and / or hydroxyethoxy groups added per glucose ring unit of cellulose, which is preferably 5 or less, more preferably 4 or less, even more preferably 3 or less, and even more preferably 2 or less, and is preferably 0.01 or more, more preferably 0.05 or more, even more preferably 0.1 or more, and even more preferably 0.15 or more.

[0050] The cellulose-based thickener is more preferably one having a structure in which the hydroxyl groups on the glucose rings of cellulose are substituted with methoxy groups having a molar substitution number within the above-mentioned range, and hydroxypropoxy groups and / or hydroxyethoxy groups having a molar substitution number within the above-mentioned range.

[0051] <(c) component> The component (c) of the present invention is a hydroxycarboxylic acid or a salt thereof. The oxycarboxylic acid is a so-called hydroxycarboxylic acid having a hydroxy group and a carboxy group in the molecule. The number of carbon atoms in the oxycarboxylic acid may be preferably 2 or more, more preferably 3 or more, and preferably 18 or less, more preferably 12 or less, even more preferably 10 or less, and even more preferably 8 or less. The number of hydroxyl groups in the oxycarboxylic acid may be preferably 1 or more, more preferably 2 or more, more preferably 4 or more, and preferably 18 or less, more preferably 12 or less, even more preferably 10 or less, and even more preferably 8 or less. The number of carboxyl groups in the oxycarboxylic acid may be preferably 1 or more, and preferably 12 or less, more preferably 6 or less, and even more preferably 3 or less.

[0052] Specific examples of the oxycarboxylic acid include one or more selected from gluconic acid, citric acid, glucoheptonic acid, arabinic acid, malic acid, tartaric acid, and salts thereof. Examples of the salt of the oxycarboxylic acid include alkali metal salts such as sodium salts, and alkaline earth metal salts such as magnesium salts. As the (c) component, from the viewpoints of inhibiting the adsorption of the (a) component to the hydraulic powder in the hydraulic composition and maintaining fluidity for a long period of time, one or more selected from gluconic acid, tartaric acid, citric acid, and salts thereof are preferred, and one or more selected from gluconic acid and salts thereof are more preferred.

[0053] <Hydraulic powder> The hydraulic powder used in the hydraulic composition of the present invention is a powder that hardens when mixed with water, and examples thereof include ordinary Portland cement, high-early-strength Portland cement, ultra-high-early-strength Portland cement, sulfate-resistant Portland cement, low-heat Portland cement, white Portland cement, and ecocement (e.g., JIS R5214, etc.). The cement is preferably selected from early-strength Portland cement, ordinary Portland cement, sulfate-resistant Portland cement, and white Portland cement, more preferably from early-strength Portland cement and ordinary Portland cement, and even more preferably from early-strength Portland cement. The hydraulic composition of the present invention preferably contains a cement selected from early-strength Portland cement and ordinary Portland cement, and more preferably contains early-strength Portland cement, as the hydraulic powder.

[0054] The hydraulic powder may contain blast furnace slag, fly ash, silica fume, anhydrous gypsum, etc., or may contain non-hydraulic limestone fine powder, etc. As the hydraulic powder, blast furnace cement, fly ash cement, or silica fume cement, which is a mixture of cement with blast furnace slag, fly ash, silica fume, etc., may be used. Also, clay such as bentonite may be contained.

[0055] <Aggregate> Aggregates include fine aggregate and coarse aggregate. Lightweight aggregate may be used depending on the application. The terminology of aggregates is taken from "Concrete Overview" (published by Gijutsu Shoin on June 10, 1998). Examples of fine aggregates include river sand, land sand, mountain sand, sea sand, lime sand, silica sand and crushed sands thereof, blast furnace slag fine aggregate, ferronickel slag fine aggregate, lightweight fine aggregate (artificial and natural), and recycled fine aggregate. Examples of coarse aggregates include those specified by number 2312 in JIS A0203-2014. Examples of coarse aggregates include river gravel, land gravel, mountain gravel, sea gravel, lime gravel, crushed stones thereof, blast furnace slag coarse aggregate, ferronickel slag coarse aggregate, lightweight coarse aggregate (artificial and natural), and recycled coarse aggregate. From the viewpoint of homogeneity of hydraulic compositions such as concrete, the maximum dimension of the coarse aggregate is preferably 1.2 mm or more, more preferably 5 mm or more, and from the viewpoint of pumpability, it is preferably 20 mm or less, more preferably 15 mm or less. The maximum dimension of this coarse aggregate is the maximum dimension of the coarse aggregate grain size obtained by a sieve test described in JIS A5005. The fine aggregate and coarse aggregate may be used in the form of a mixture of different types, or a single type of aggregate may be used.

[0056] <Composition, etc.> The hydraulic composition of the present invention contains, from the viewpoints of initial fluidity and long-term fluidity retention, preferably 0.6 mass % or more, more preferably 0.7 mass % or more, even more preferably 0.8 mass % or more of component (a) relative to the hydraulic powder, and preferably 5.0 mass % or less, more preferably 3.0 mass % or less, even more preferably 2.0 mass % or less.

[0057] In the hydraulic composition of the present invention, when the component (a) contains the components (a1) and (a2), the mass ratio (a1) / (a2) of the content of the component (a1) to the content of the component (a2) is, from the viewpoint of temperature versatility of fluidity, preferably 40 / 60 or more, more preferably 50 / 50 or more, even more preferably 60 / 40 or more, even more preferably 70 / 30 or more, and preferably 95 / 5 or less, more preferably 90 / 10 or less, even more preferably 85 / 15 or less.

[0058] The hydraulic composition of the present invention contains the component (b) in an amount of preferably 0.3 mass % or more, more preferably 0.4 mass % or more, even more preferably 0.5 mass % or more, and preferably 4.0 mass % or less, more preferably 3.0 mass % or less, even more preferably 2.5 mass % or less, and even more preferably 2.0 mass % or less, based on water, from the viewpoints of non-separation in water and control of the adsorption rate of the component (a) to the hydraulic powder.

[0059] When the hydraulic composition of the present invention contains the component (b1) as the component (b), the hydraulic composition contains the component (b1) in an amount of preferably 0.50% by mass or more, more preferably 0.75% by mass or more, even more preferably 1.00% by mass or more, based on water, from the viewpoints of non-separation in water and control of the adsorption rate of the component (a) to the hydraulic powder, and preferably 4.00% by mass or less, more preferably 3.0% by mass or less, even more preferably 2.5% by mass or less, and even more preferably 2.0% by mass or less. In the present invention, when the component (b12) is contained as the component (b1), the mass of the component (b12) is the value calculated as the sodium salt of the component (b12).

[0060] In the hydraulic composition of the present invention, when the component (b1) contains the compounds (b11-1), (b11-2), and (b12), from the viewpoints of non-separation in water and control of the adsorption rate of the component (a) to the hydraulic powder, the content of the compound (b11-1) in the component (b1) is preferably 10% by mass or more, more preferably 14% by mass or more, and preferably 25% by mass or less, and more preferably 20% by mass or less, the content of the compound (b11-2) is preferably 70% by mass or more, more preferably 75% by mass or more, and preferably 85% by mass or less, and more preferably 80% by mass or less, and the content of the component (b12) is preferably 5% by mass or more, more preferably 7.5% by mass or more, and preferably 20% by mass or less, and more preferably 15% by mass or less, from the viewpoints of anti-separation in water and control of the adsorption rate of the component (a) to the hydraulic powder.

[0061] In the thickener composition for hydraulic compositions of the present invention, when the compound (b1) contains the compounds (b11-3), (b11-2), and (b12), from the viewpoints of non-separability in water and control of the adsorption rate of the component (a) to the hydraulic powder, the content of the compound (b11-3) in the component (b) is preferably 10% by mass or more, more preferably 14% by mass or more, and preferably 25% by mass or less, and more preferably 20% by mass or less, the content of the compound (b11-2) is preferably 70% by mass or more, more preferably 75% by mass or more, and preferably 85% by mass or less, and more preferably 80% by mass or less, and the content of the component (b12) is preferably 5% by mass or more, more preferably 7.5% by mass or more, and preferably 20% by mass or less, and more preferably 15% by mass or less, from the viewpoints of non-separability in water and control of the adsorption rate of the component (a) to the hydraulic powder.

[0062] When the hydraulic composition of the present invention contains the component (b2) as the component (b), the hydraulic composition contains the component (b2) in an amount of preferably 0.30% by mass or more, more preferably 0.40% by mass or more, even more preferably 0.50% by mass or more, based on water, from the viewpoints of non-separation in water and control of the adsorption rate of the component (a) to the hydraulic powder, and preferably 2.0% by mass or less, more preferably 11.5% by mass or less, even more preferably 1.00% by mass or less.

[0063] The hydraulic composition of the present invention contains the component (c) in an amount of preferably 0.02% by mass or more, more preferably 0.04% by mass or more, and even more preferably 0.06% by mass or more, based on the hydraulic powder, from the viewpoint of suppressing fluctuations due to temperature changes, and from the viewpoint of strength development after 24 hours, preferably 0.18% by mass or less, more preferably 0.15% by mass or less, and even more preferably 0.13% by mass or less. In the present invention, the mass of component (c) is expressed as the value of component (c) converted into a sodium salt.

[0064] In the hydraulic composition of the present invention, the mass ratio (a) / (c) of the content of the component (a) to the content of the component (c) is preferably 4.5 or more, more preferably 5.5 or more, even more preferably 6.0 or more, and is preferably 40 or less, more preferably 38 or less, even more preferably 36 or less, still more preferably 30 or less, still more preferably 25 or less, and even more preferably 20 or less, from the viewpoint of suppressing the spread of the hydraulic composition and fluctuation due to temperature change.

[0065] The hydraulic composition of the present invention contains water. From the viewpoint of strength development, the hydraulic composition of the present invention has a water / hydraulic powder ratio (W / C) of preferably 30% by mass or more, more preferably 33% by mass or more, even more preferably 36% by mass or more, and preferably 45% by mass or less, more preferably 43% by mass or less, even more preferably 41% by mass or less. Here, the water / hydraulic powder ratio (W / C) is the mass percentage (mass%) of water and hydraulic powder in the hydraulic composition, and is calculated as water / hydraulic powder×100. In addition, when the hydraulic powder includes powders selected from powders having pozzolanic action, powders having latent hydraulic properties, and stone powder (calcium carbonate powder) in addition to powders having properties that harden through hydration reactions such as cement, the amounts of these powders are also included in the amount of hydraulic powder in this invention. In addition, when the powder having properties that harden through hydration reactions contains a high-strength admixture, the amount of the high-strength admixture is also included in the amount of hydraulic powder. This also applies to other parts by mass that are related to the mass of the hydraulic powder.

[0066] The hydraulic composition of the present invention preferably has an aggregate content of 1000 kg / m 3 More preferably, 1350 kg / m 3 More preferably, 1500 kg / m 3 More than 2300 kg / m 3 Less than or equal to 2150 kg / m 3 More preferably, 1900 kg / m 3 The following is the result. The hydraulic composition of the present invention preferably has a fine aggregate content of 400 kg / m 3More preferably, 500 kg / m 3 More preferably, 600 kg / m 3 More than 1100 kg / m 3 Less than or equal to 1000 kg / m 3 More preferably, 900 kg / m or less 3 The following is the result. The hydraulic composition of the present invention preferably has a coarse aggregate content of 500 kg / m 3 More preferably, 750 kg / m 3 More preferably, 800 kg / m 3 More than 1200 kg / m 3 Less than or equal to 1150 kg / m 3 More preferably, 1000 kg / m or less 3 The following is the result.

[0067] The hydraulic composition of the present invention has a fine aggregate ratio of preferably 30% by volume or more, more preferably 34% by volume or more, and preferably 50% by volume or less, more preferably 46% by volume or less. s / a is calculated based on the volumes of fine aggregate (S) and coarse aggregate (G) as s / a=[S / (S+G)]×100 (volume %).

[0068] The hydraulic composition may contain components other than the components (a), (b), and (c), such as an air-enhancing agent, a foaming agent, a foaming agent, a waterproofing agent, a fluidizing agent, and an antifoaming agent, within the range that does not affect the effects of the present invention.

[0069] The hydraulic composition of the present invention can be used for various purposes. For example, it can be used for high-fluidity concrete, underwater non-segregating concrete, lightweight high-fluidity concrete, water-permeable concrete, cast-in-place lining method (ECL method), or SENS method. Among them, it is preferable for use in the SENS method.

[0070] From the viewpoint of handleability, the hydraulic composition of the present invention has a time until the slump flow reaches 50 cm, as measured by the method described in JIS A1150 (2007), of preferably 15 seconds or more, more preferably 17 seconds or more, and preferably 45 seconds or less, more preferably 40 seconds or less.

[0071] <Method for producing hydraulic composition> The hydraulic composition of the present invention can be produced by mixing the components (a), (b), (c), hydraulic powder, and water. That is, the present invention provides a method for producing a hydraulic composition containing the components (a), (b), (c), hydraulic powder, and water. The items described for the hydraulic composition of the present invention can be appropriately applied to the method for producing the hydraulic composition of the present invention. For example, specific examples and preferred aspects of each component are the same as those of the hydraulic composition of the present invention. In addition, the content and mass ratio of each component in the hydraulic composition of the present invention can be applied to the method for producing the hydraulic composition of the present invention by replacing the content of each component with the mixed amount.

[0072] In the method for producing a hydraulic composition of the present invention, it is preferable to produce a hydraulic composition in which the time until the slump flow reaches 50 cm as measured by the method described in JIS A1150 (2007) is preferably 15 seconds or more, more preferably 17 seconds or more, and preferably 45 seconds or less, more preferably 40 seconds or less, from the viewpoint of handleability. EXAMPLES

[0073] The components used in the examples and comparative examples are shown below. The copolymer used as component (a) is as follows: Copolymer 1: MEPEG(120) ester / MAA=20 / 80 (mol%) copolymer, sodium salt, weight average molecular weight 50,000 Copolymer 2: MEPEG(120) ester / MAA=35 / 65 (mol%) copolymer, sodium salt, weight average molecular weight 60,000 Copolymer 3: MEPEG(23) ester / MAA=27 / 73 (mol%) copolymer, sodium salt, weight average molecular weight 40,000 Copolymer 4: MEPEG(120) ester / MAA=10 / 90 (mol%) copolymer, sodium salt, weight average molecular weight 40,000 Copolymer 5: MEPEG(120) ester / MAA=45 / 55 (mol%) copolymer, sodium salt, weight average molecular weight 50,000 The monomers of the above copolymers are as follows. MEPEG (120) ester: methoxypolyethylene glycol (120) monomethacrylate (the number in parentheses is the average number of moles of ethylene oxide added. The same applies below), monomer (1a) MEPEG (23) Ester: Methoxypolyethylene glycol (23) monomethacrylate, monomer (1a) · MAA: Sodium methacrylate, monomer (2a)

[0074] <Component (a)> a-1: copolymer 1, the average proportion of monomer (2a) in all constituent monomers of component (a) is 80 mol% a-2: copolymer 2, average proportion of monomer (2a) in all constituent monomers of component (a) is 65 mol% a-3: a mixture of copolymer 1 / copolymer 4=75 / 25 (mass ratio), the average ratio of monomer (2a) to all constituent monomers of component (a) was 82.5 mol% a-4: a mixture of copolymer 1 / copolymer 4 = 50 / 50 (mass ratio), the average ratio of monomer (2a) to all constituent monomers of component (a) was 85 mol% a-5: a mixture of copolymer 1 / copolymer 2 = 50 / 50 (mass ratio), the average ratio of monomer (2a) to all constituent monomers of component (a) was 72.5 mol% a-6: copolymer 3, average proportion of monomer (2a) in all constituent monomers of component (a) is 73 mol%

[0075] <Component (a') (comparison component for component (a))> a'-1: copolymer 4, the average proportion of monomer (2a) in all constituent monomers of component (a) is 90 mol% a'-2: copolymer 5, average proportion of monomer (2a) in all constituent monomers of component (a) is 55 mol%

[0076] With regard to the average proportion of monomer (2a) in all constituent monomers of component (a) or component (a'), when one copolymer containing monomer (1a) and monomer (2a) as constituent monomers is used as component (a), the proportion (mol %) of monomer (2a) in all constituent monomers in this copolymer is taken as the average proportion of monomer (2a); when two or more copolymers containing monomer (1a) and monomer (2a) as constituent monomers are used as component (a), the average proportion of monomer (2a) in all constituent monomers in the entire copolymer is calculated from the proportion (mol %) of monomer (2a) in all constituent monomers in each copolymer and the proportion (mass %) of each copolymer in component (a), and this is taken as the average proportion of monomer (2a). For example, a-3 uses two types of copolymers, copolymer 1 (ratio of monomer (2a) 80 mol %) and copolymer 4 (ratio of monomer (2a) 90 mol %), in a mass ratio of 75 / 25, and therefore the average ratio of monomer (2a) in all constituent monomers of component (a) is 80×0.75+90×0.25=82.5.

[0077] <(b) Component> b-1: a mixture of oleyl dimethylamine oxide / oleic acid amidopropyl dimethylamine oxide / sodium m-xylene sulfonate = 14.7 / 75.5 / 9.8 (mass%), component (b1) b-2: Cellulose-based thickener, (b2) component, Asuka Clean, manufactured by Shin-Etsu Chemical Co., Ltd.

[0078] <(c) component> c-1: Sodium gluconate ·c-2: Sodium tartrate · C-3: Sodium citrate

[0079] [Method of preparing hydraulic composition] Coarse aggregate (G), fine aggregate (S1, S2), and hydraulic powder (C) were added to a forced twin-shaft mixer (IHI Corporation) in the proportions shown in Table 1, and dry mixing was performed for 10 seconds. Then, water (W) containing component (a) and / or component (a') and component (c) was added so as to obtain the contents shown in Table 2, and the mixture was stirred for 90 seconds (stirring speed: 40 rpm), and component (b) was added so as to obtain the contents shown in Table 2, and the mixture was stirred for 60 seconds to prepare a hydraulic composition. In Comparative Example 2, a hydraulic composition was prepared without adding component (c). In Table 2, the content of component (a) or (a') indicates the content (% by mass) relative to the hydraulic powder in the hydraulic composition, the content of component (b) indicates the content (% by mass) relative to the water in the hydraulic composition, and the content of component (c) indicates the content (% by mass) relative to the hydraulic powder in the hydraulic composition.

[0080] [Table 1]

[0081] The materials listed in Table 1 are as follows. Water (W): Tap water High-early-strength Portland cement (C): Taiheiyo Cement Corporation / Sumitomo Osaka Cement Co., Ltd. = 50 / 50 (mass ratio), density 3.14 g / cm 3 ·Fine aggregate (S1): Mountain sand from Joyo, Kyoto, surface dry density 2.56g / cm 3 Fine aggregate (S2): Coarse sand from Ibigawa River, Gifu Prefecture, surface dry density 2.60g / cm 3 Coarse aggregate (G): Crushed stone 1005 from Ieshima, Hyogo Prefecture, surface dry density 2.60g / cm 3

[0082] [Liquidity evaluation] Each hydraulic composition prepared according to JIS A1150 was adjusted to the temperature (20°C or 30°C) shown in Table 2, and each hydraulic composition immediately after kneading (0 minutes) and 4 hours after kneading was filled into a slump cone, the slump cone was raised, and the time from the start of raising the slump cone to the time when the spread of the hydraulic composition first reached a circle of 500 mm in diameter drawn on the slump flow plate was measured with a stopwatch, and this measured time was defined as the 50 cm flow time. The results are shown in Table 2. Table 2 also shows the rate of change from the flow time at 20°C to the flow time at 30°C for the hydraulic composition immediately after kneading and the hydraulic composition 4 hours after kneading. The smaller the rate of change, the less the fluidity of the hydraulic composition is affected by temperature. For Comparative Examples 3 and 4, the hydraulic composition did not spread to 50 cm, and therefore was described as "not reached" in the table.

[0083] [Evaluation of underwater non-separability] According to JSCE-D 104-2007, 800 ml of ion-exchanged water was placed in a 1000 ml glass beaker, and 500 g of each prepared hydraulic composition was weighed out and divided into 10 portions, each portion being gently allowed to fall freely from the water surface using a spatula. All samples were poured in within 30 seconds, and after leaving for 3 minutes, approximately 600 ml of the supernatant was collected using a suction device, and 300 ml of that was taken in a measuring cylinder. Using filter paper dried at 105°C for 1 hour, 300 ml of the sample water was poured and suction filtered. The filter paper with the residue on it was transferred to a tray and dried at 105°C for 2 hours, the amount of suspended solids was calculated, and the inseparability in water was evaluated. In this evaluation, a suspended solids amount of 500 mg / L or less was evaluated as "good" for inseparability in water, and an amount of less than 500 mg / L was evaluated as "bad", as shown in Table 2.

[0084] [Strength evaluation of specimens] For each of the prepared hydraulic compositions, a test specimen was prepared in accordance with JIS A1132, and cured indoors at a temperature of 20±2°C to prevent drying until the formwork was removed. The formwork was removed 24 hours after contact with water, and the strength was tested. The strength of the specimens was measured according to JIS A1108. The results are shown in Table 2. The target compressive strength after 24 hours was 15N / mm 2 The above is preferred.

[0085] [Table 2]

[0086] It can be seen that in Examples 1 to 12, the rate of change in flow time due to temperature change both immediately after kneading and 4 hours after kneading is smaller than that in Comparative Example 1 in which the average proportion of monomer (2a) in the copolymer exceeds 88 mol %. On the other hand, in Comparative Examples 3 and 4 in which the average proportion of monomer (2a) in the copolymer is less than 60 mol %, the hydraulic composition cannot spread to 50 cm even when the amount of copolymer added is increased, and the 24-hour strength is also poor. Furthermore, in Comparative Example 2, which does not contain component (c), the rate of change in flow time after 4 hours due to temperature change was large. Furthermore, it is clear that Examples 1 to 12 have non-separation properties in water.

Claims

1. A hydraulic composition containing the following component (a), component (b), component (c), hydraulic powder, water, and aggregate. Component (a): A copolymer containing the monomer (1a) represented by the following general formula (1a) and the monomer (2a) represented by the following general formula (2a) as constituent monomers, and the average proportion of the monomer (2a) in all constituent monomers is 60 mol% or more and 88 mol% or less. Component (b): A thickener Component (c): An oxycarboxylic acid or its salt 【Chemical Formula 1】 [In the formula, R １ａ , R ２ａ : May be the same or different, and is a hydrogen atom or a methyl group R ３ａ : A hydrogen atom or -COO(AO) ｎ１ X １ R ４ａ : A hydrogen atom or an alkyl group having 1 to 4 carbon atoms AO: A group selected from an ethyleneoxy group and a propyleneoxy group n1: The average number of moles of addition of AO, and is a number of 20 or more and 130 or less q1: A number of 0 or more and 2 or less p1: 0 or 1 is shown. ] 【Chemical Formula 2】 [In the formula, R ５ａ , R ６ａ , R ７ａ : May be the same or different, and is a hydrogen atom, a methyl group or (CH ２ ) ｒ COOM ２ and (CH ２ ) ｒ COOM ２ is COOM １ or another (CH ２ ) ｒ COOM ２ may form an anhydride, and in that case, M of those groups １ , M ２ does not exist. M １ 、M ２ : may be the same or different, and is a hydrogen atom, an alkali metal, an alkaline earth metal (1 / 2 atom), an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroalkyl group or an alkenyl group r: a number from 0 to 2 inclusive is shown. ]

2. The hydraulic composition according to claim 1, wherein the average proportion of monomer (1a) in all the constituent monomers of component (a) is 12 mol% or more and 40 mol% or less.

3. The hydraulic composition according to claim 1 or 2, wherein component (c) is at least one selected from gluconic acid, tartaric acid, citric acid, and salts thereof.

4. The hydraulic composition according to claim 1 or 2, containing component (c) in an amount of 0.02% by mass or more and 0.18% by mass or less based on the hydraulic powder.

5. The hydraulic composition according to claim 1 or 2, wherein component (b) is (b1) an amine oxide surfactant and an anionic aromatic compound, or (b2) a cellulose thickener.

6. The hydraulic composition according to claim 1 or 2, wherein the time until the slump flow measured by the method described in JIS A1150 reaches 50 cm is 15 seconds or more and 45 seconds or less.

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