Ground consolidation agent and method for consolidating ground using the same

Abstract

The amount of nonionic surfactant detected under flowing water is low, indicating excellent performance as a ground consolidating agent. [Solution] The ground consolidator comprises component (A) containing a polyol (a), an amine compound (b) having a primary amino group and / or a secondary amino group, a catalyst (c), and a flame retardant (d), and component (B) containing an aromatic polyisocyanate. Polyol (a) includes an ether polyol (a1) having 1.5 to 2.5 functional groups and a hydroxyl value of 400 to 1100 mgKOH / g, and a polyester polyol (a2) having a hydroxyl value of 100 to 400 mgKOH / g. 90% by mass or more of the ether polyol contained in polyol (a) is ether polyol (a1). The total amount of ether polyol (a1) and polyester polyol (a2) in polyol (a) is 50% by mass or more.

Description

Technical Field

[0001] The present invention relates to a ground consolidation agent and a method for consolidating the ground using the same.

Background Art

[0002] Conventionally, for strengthening the stability of unstable rock masses or ground, injection of inorganic or organic grouts has been carried out. As such a ground consolidation agent, a urethane-based ground consolidation agent mainly composed of polyol and isocyanate is useful in that it has a high consolidation rate and can consolidate the ground and develop strength in a short time.

[0003] For example, Patent Document 1 discloses a chemical liquid composition comprising a component (A) containing a polyol and an amine compound and a component (B) containing an isocyanate, and substantially free of water. In this chemical liquid composition, polyether polyol and castor oil-based polyester polyol are used as the polyol, and an amine compound having a primary or secondary amino group is used as the amine compound.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the case of urethane-based ground consolidation agents, when injected into rock masses or ground under running water, it has been a problem that nonionic surfactants are detected in the outflow components into the environment. Therefore, there is a demand for a ground consolidation agent with good performance while reducing the detection amount of nonionic surfactants.

[0006] In view of the above, the embodiments of the present invention aim to provide a ground consolidator that exhibits a low amount of nonionic surfactant and excellent performance as a ground consolidator, and a method for consolidating ground using the same. [Means for solving the problem]

[0007] The present invention includes embodiments shown below. [1] Component (A) comprises a polyol (a), an amine compound having a primary amino group and / or a secondary amino group (b), a catalyst (c), and a flame retardant (d), The material comprises component (B) containing an aromatic polyisocyanate, The polyol (a) comprises an ether-based polyol (a1) having 1.5 to 2.5 functional groups and a hydroxyl value of 400 to 1100 mgKOH / g, and a polyester polyol (a2) having a hydroxyl value of 100 to 400 mgKOH / g. 90% by mass or more of the ether-based polyol contained in the polyol (a) is the ether-based polyol (a1), A ground consolidator wherein the total amount of the ether-based polyol (a1) and the polyester polyol (a2) in the polyol (a) is 50% by mass or more.

[0008] [2] The ground consolidator according to [1], wherein the content of the ether-based polyol (a1) in the polyol (a) is 5 to 95% by mass, and the content of the polyester polyol (a2) in the polyol (a) is 5 to 95% by mass. [3] The ground consolidator according to [1] or [2], wherein the content of the amine compound (b) in component (A) is 1 to 30% by mass. [4] The ground consolidator according to any one of [1] to [3], wherein the aromatic polyisocyanate comprises at least one selected from the group consisting of diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, and modified forms thereof. [5] A method for solidifying a rock mass or ground, comprising the steps of drilling a plurality of holes in the rock mass or ground at predetermined intervals, inserting hollow bolts into the holes, and injecting a ground solidifying agent described in any one of items [1] to [4] into the rock mass or ground through the opening of the bolts to solidify it. [Effects of the Invention]

[0009] The ground consolidator according to the embodiment of the present invention exhibits a low detection amount of nonionic surfactant and excellent performance as a ground consolidator. [Modes for carrying out the invention]

[0010] The ground consolidator according to this embodiment comprises component (A), which includes a polyol (a), an amine compound (b), a catalyst (c), and a flame retardant (d), and component (B), which includes an aromatic polyisocyanate. The ground consolidator is typically a two-component curing type, with component (A) as liquid A and component (B) as liquid B. In addition to components (A) and (B), a third component may be included as an optional component.

[0011] [(A) component] (A) Component is a component containing an active hydrogen compound. An active hydrogen compound is a compound having one or more active hydrogen groups in its molecule (excluding water). An active hydrogen group is a group containing a hydrogen atom that reacts with an isocyanate group, and examples include hydroxyl groups, primary amino groups (-NH2), and secondary amino groups (-NHR).

[0012] (Polyol (a)) Component (A) contains polyol (a) as an active hydrogen compound. Polyol (a) includes ether polyol (a1) having 1.5 to 2.5 functional groups and a hydroxyl value of 400 to 1100 mgKOH / g, and polyester polyol (a2) having a hydroxyl value of 100 to 400 mgKOH / g, wherein 90% by mass or more of the ether polyol contained in polyol (a) is ether polyol (a1).

[0013] Here, ether polyols refer to polyols that contain an ether bond (-O-) in their molecule, and are not limited to polyether polyols having multiple ether bonds, but also include polyols having one ether bond. However, polyester polyols are not included in ether polyols, even if they have an ether bond in their molecule. Here, polyester polyols refer to polyols having multiple ester bonds (-COO-) in their molecule.

[0014] According to this embodiment, by substantially using only a specific ether polyol (a1) as the ether polyol used in combination with the polyester polyol (a2), it is possible to reduce the amount of nonionic surfactant detected in the components released into the environment under flowing water while exhibiting the performance of a ground consolidator such as watertightness and ground improvement properties.

[0015] In detail, a functional group count of ether polyol (a1) of 1.5 or more enhances the strength after curing and improves the performance of the ground consolidator. A functional group count of ether polyol (a1) of 2.5 or less reduces the amount of nonionic surfactant detected. Furthermore, a hydroxyl value of ether polyol (a1) of 400 mgKOH or more enhances the strength after curing and improves the performance of the ground consolidator, and also reduces the amount of nonionic surfactant detected.

[0016] The number of functional groups in the ether polyol (a1) is preferably 1.7 to 2.3, more preferably 1.8 to 2.2, more preferably 1.9 to 2.1, and even more preferably 2.0. Here, the number of functional groups refers to the number of hydroxyl groups per molecule of the polyol (weighted average value according to the molar ratio).

[0017] The hydroxyl value of the ether-based polyol (a1) is preferably 420 to 1100 mgKOH / g, more preferably 450 to 1000 mgKOH / g, and even more preferably 500 to 900 mgKOH / g. In this specification, the hydroxyl value is measured in accordance with Method A of JIS K1557-1:2007.

[0018] As the ether-based polyol (a1), an aliphatic ether-based polyol, an aromatic ether-based polyol, or a combination of both may be used. An aliphatic ether-based polyol refers to an ether-based polyol that does not have an aromatic ring in the molecule. An aromatic ether-based polyol refers to an ether-based polyol that has an aromatic ring in the molecule.

[0019] Examples of the aliphatic ether-based polyol include aliphatic diols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, butylene glycol, 1,3-butanediol, 1,4-butanediol, and 1,6-hexanediol, aliphatic active hydrogen compounds such as monoethanolamine, diethanolamine, and ethylenediamine, and aliphatic polyether polyols obtained by using one or more alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide and subjecting them to addition polymerization by a known method. Examples of the aliphatic ether-based polyol also include, for example, diethylene glycol, triethylene glycol, dipropylene glycol, and tripropylene glycol. Any one of these aliphatic ether-based polyols may be used alone, or two or more of them may be used in combination.

[0020] Examples of the aromatic ether polyol include aromatic polyether polyols obtained by using one or more alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide for aromatic active hydrogen compounds such as aniline, benzene diol, and bisphenol compounds and subjecting them to addition polymerization by a known method. Regarding the aromatic ether polyol, any one type may be used, or two or more types may be used in combination.

[0021] The polyol (a) may contain an ether polyol other than the above ether polyol (a1), but even if it contains such, the amount is preferably small. Specifically, in the present embodiment, 90% by mass or more of the ether polyol contained in the polyol (a) is the ether polyol (a1). That is, the content of the ether polyol (a1) in 100% by mass of the ether polyol contained in the polyol (a) is 90% by mass or more, preferably 95% by mass or more, and more preferably 100% by mass. That is, the ether polyol may consist only of the ether polyol (a1). Thereby, the detected amount of the nonionic surfactant under running water can be reduced.

[0022] The polyol (a) includes a polyester polyol (a2) having a hydroxyl value of 100 to 400 mgKOH / g together with the above ether polyol (a1). By using such a polyester polyol having a relatively small hydroxyl value in combination, it is possible to enhance the performance of the base consolidation agent while reducing the detected amount of the nonionic surfactant.

[0023] In detail, a hydroxyl value of 100 mgKOH / g or more of polyester polyol (a2) can increase the strength after curing, thereby improving watertightness and ground improvement properties. A hydroxyl value of 400 mgKOH / g or less of polyester polyol (a2) can suppress brittleness after curing, thereby improving ground improvement properties. The hydroxyl value of polyester polyol (a2) is preferably 130 to 350 mgKOH / g or less, more preferably 150 to 300 mgKOH / g, and even more preferably 150 to 250 mgKOH / g. In one embodiment, the hydroxyl value of the polyester polyol may be 100 to 250 mgKOH / g, or 100 to 161 mgKOH / g.

[0024] The number of functional groups in the polyester polyol (a2) is not particularly limited, but is preferably 1.5 to 4.0, more preferably 1.8 to 3.0, and even more preferably 1.9 to 3.0.

[0025] Examples of polyester polyols (a2) include those obtained by reacting a polyhydric alcohol, such as a dihydric alcohol, with a dibasic acid. These may be aliphatic polyester polyols, aromatic polyester polyols, or a combination of both. Aliphatic polyester polyols are polyester polyols that do not contain an aromatic ring in their molecule. Aromatic polyester polyols are polyester polyols that contain an aromatic ring in their molecule.

[0026] Examples of aliphatic polyester polyols include aliphatic polyols obtained by reacting an aliphatic diol with an aliphatic dibasic acid, and castor oil-based polyester polyols (i.e., castor oil-based aliphatic polyester polyols). Either one or two or more may be used in combination. Examples of aliphatic diols constituting the aliphatic polyol include ethylene glycol, diethylene glycol, propylene glycol, butylene glycol, 1,3-butanediol, 1,4-butanediol, 3-methyl-1,5-pentanediol, and 1,6-hexanediol. Examples of aliphatic dibasic acids include adipic acid, succinic acid, sebacic acid, azelaic acid, maleic acid, and fumaric acid.

[0027] Castor oil-based aliphatic polyester polyols are polyols produced using castor oil, castor oil fatty acids, hydrogenated castor oil obtained by hydrogenating castor oil, and hydrogenated castor oil fatty acids obtained by hydrogenating castor oil fatty acids. Specific examples of castor oil-based aliphatic polyester polyols include castor oil, transesterified products of castor oil and other natural oils and fats, reaction products of castor oil and polyhydric alcohols, esterification reaction products of castor oil fatty acids and polyhydric alcohols, hydrogenated castor oil, transesterified products of hydrogenated castor oil and other natural oils and fats, reaction products of hydrogenated castor oil and polyhydric alcohols, and esterification reaction products of hydrogenated castor oil fatty acids and polyhydric alcohols. Any one of these may be used, or two or more may be used in combination.

[0028] Examples of aromatic polyester polyols include aromatic polyols obtained by reacting a diol with an aromatic dibasic acid, and castor oil-based aromatic polyester polyols. Either one or two or more may be used in combination. Examples of diols constituting the aromatic polyol include ethylene glycol, diethylene glycol, propylene glycol, butylene glycol, 1,3-butanediol, 1,4-butanediol, 3-methyl-1,5-pentanediol, and 1,6-hexanediol. Examples of aromatic dibasic acids include phthalic acid, terephthalic acid, and isophthalic acid. Castor oil-based aromatic polyester polyols are castor oil-modified polyols containing an aromatic skeleton.

[0029] The hydroxyl value of polyester polyol (a2) is preferably 400 mg KOH / g or less, and more preferably 100 to 350 mg KOH / g or less, in the case of aliphatic polyester polyols. That is, polyester polyol (a2) preferably contains aliphatic polyester polyols with a hydroxyl value of 100 to 400 mg KOH / g (more preferably 100 to 350 mg KOH / g). The hydroxyl value of polyester polyol (a2) is preferably 250 mg KOH / g or less, and more preferably 100 to 230 mg KOH / g or less, in the case of aromatic polyester polyols. That is, polyester polyol (a2) preferably contains aromatic polyester polyols with a hydroxyl value of 100 to 250 mg KOH / g (more preferably 100 to 230 mg KOH / g). Aromatic polyester polyols have a more rigid molecular structure compared to aliphatic polyester polyols. By using those with a lower hydroxyl value, it is easier to suppress brittleness after hardening, thereby enhancing the effect of improving ground improvement.

[0030] Polyol (a) may or may not contain polyols other than ether-based polyol (a1) and polyester polyol (a2). More specifically, the total amount of ether-based polyol (a1) and polyester polyol (a2) in polyol (a) is 50% by mass or more. That is, the total content of ether-based polyol (a1) and polyester polyol (a2) is 50% by mass or more, preferably 70% by mass or more, more preferably 90% by mass or more, and may also be 100% by mass, based on 100% by mass of polyol (a).

[0031] Polyols other than ether polyols (a1) and polyester polyols (a2) are not particularly limited and include ether polyols other than (a1), polyester polyols other than (a2), and polyols that do not contain ether or ester bonds. Polyols that do not contain ether or ester bonds are not particularly limited and include, for example, ethylene glycol, propylene glycol, butylene glycol, hexanediol, octanediol, nonanediol and other alkanediols, and glycerin and other alkanetriols. Any one of these may be used, or two or more may be used in combination.

[0032] The content of ether polyol (a1) in polyol (a) is not particularly limited and may be, for example, 5 to 95% by mass, 10 to 85% by mass, 15 to 80% by mass, or 20 to 75% by mass. The content of polyester polyol (a2) in polyol (a) is not particularly limited and may be, for example, 5 to 95% by mass, 10 to 85% by mass, 15 to 80% by mass, or 20 to 75% by mass. The content of alkanediol and / or alkanetriol in polyol (a) is not particularly limited and may be, for example, 0 to 50% by mass, 0 to 30% by mass, 0 to 10% by mass, or 5% by mass or more in one embodiment.

[0033] The content of ether polyol (a1) in component (A) (i.e., the content of (a1) relative to 100% by mass of component (A)) is preferably 1 to 60% by mass, more preferably 2 to 57% by mass, more preferably 5 to 50% by mass, more preferably 10 to 45% by mass, and still more preferably 15 to 40% by mass. The content of polyester polyol (a2) in component (A) is preferably 1 to 70% by mass, more preferably 5 to 65% by mass, more preferably 10 to 55% by mass, more preferably 15 to 45% by mass, and still more preferably 20 to 40% by mass.

[0034] In polyol (a), the mass ratio (a2) / (a1) of polyester polyol (a2) to ether polyol (a1) is not particularly limited and may be, for example, 0.1 to 15, 0.1 to 4.0, 0.15 to 3.3, 0.2 to 3.0, 0.3 to 2.5, 0.4 to 2.0, or 0.5 to 1.6. A mass ratio (a2) / (a1) of 0.1 or higher makes it easier to suppress brittleness after hardening and improve ground improvement properties. A mass ratio (a2) / (a1) of 15 or lower makes it easier to increase strength after hardening and improve ground improvement properties.

[0035] (Amine compound (b)) Component (A) contains an amine compound (b) having a primary amino group and / or a secondary amino group as an active hydrogen compound. The amine compound (b) may have a primary amino group, a secondary amino group, or both. The amine compound (b) acts as a modifier, and by including the amine compound (b), reactivity can be increased to improve water-stopping properties, and the amount of nonionic surfactant detected can be reduced. Note that even if the amine compound (b) has multiple hydroxyl groups in its molecule, it is not included in the polyol (a).

[0036] Examples of amine compounds (b) include aliphatic monoamines, alicyclic monoamines, aromatic monoamines, heterocyclic monoamines, aliphatic diamines, alicyclic diamines, aromatic diamines, aliphatic triamines, alicyclic triamines, aromatic triamines, and hydrazines.

[0037] Examples of aliphatic monoamines include alkyl monoamines such as monomethylamine, monoethylamine, monobutylamine, dimethylamine, diethylamine, di-n-propylamine, diisopropylamine, dibutylamine, diamylamine, dihexylamine, methylethylamine, methylpropylamine, methylisopropylamine, ethylpropylamine, ethylisopropylamine, N-methyldodecylamine, and bis(2-ethylhexyl)amine; and alkanol monoamines such as monoethanolamine, diethanolamine, and diisopropanolamine.

[0038] Examples of alicyclic monoamines include cyclopentylamine, cyclohexylamine, N-methylcyclohexylamine, N-ethylcyclohexylamine, and dicyclohexylamine.

[0039] Examples of aromatic monoamines include N-methylbenzylamine, dibenzylamine, benzylamine, and p-methylbenzylamine.

[0040] Examples of heterocyclic monoamines include morpholine, pyrrolidine, piperidine, and pyrazole.

[0041] Examples of aliphatic diamines include ethylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, tetramethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, neopentanediamine, and polyetherdiamine. Here, polyetherdiamine is a compound obtained by converting the hydroxyl groups of polyoxyalkylene glycols, which are obtained by addition polymerization of propylene oxide and / or ethylene oxide to water, ethylene glycol, or propylene glycol, to primary amino groups, and is also called polyoxyalkylenediamine.

[0042] Examples of alicyclic diamines include 4,4'-diaminocyclohexylmethane, isophorone diamine, bisaminomethylcyclohexane, 2,5- or 2,6-diaminomethylbicyclo[2,2,1]heptane, and diaminocyclohexane.

[0043] Examples of aromatic diamines include diaminodiphenylmethane, diaminodiphenyl ether, xylylenediamine, phenylenediamine, diethyltoluenediamine (e.g., 3,5-diethyl-2,4-diaminotoluene, 3,5-diethyl-2,6-diaminotoluene), and 4,4'-methylenebis[N-(1-methylpropyl)aniline].

[0044] Examples of aliphatic triamines include diethylenetriamine and polyethertriamine. Here, polyethertriamine is a compound obtained by converting the hydroxyl groups of polyoxyalkylenetriols, which are obtained by addition polymerization of propylene oxide and / or ethylene oxide to glycerin or trimethylolpropane, to primary amino groups, and is also called polyoxyalkylenetriamine.

[0045] Examples of alicyclic triamines include 1,3,5-tris(aminomethyl)cyclohexane. Examples of aromatic triamines include 1,3,5-tris(aminomethyl)benzene.

[0046] These amine compounds (b) may be used individually or in combination of two or more.

[0047] In one embodiment, the amine compound (b) preferably contains a primary amine (b1) having a primary amino group, more preferably a primary diamine (b2), and even more preferably an aliphatic primary diamine and / or an aromatic primary diamine (b3). A secondary amine having a secondary amino group may be used in combination with the primary amine (b1).

[0048] The content of amine compound (b) in component (A) (i.e., the amount of (b) relative to 100% by mass of component (A)) is preferably 1 to 30% by mass, more preferably 1.5 to 25% by mass, more preferably 2.0 to 20% by mass, more preferably 2.5 to 15% by mass, and even more preferably 3.0 to 10% by mass. By having a content of amine compound (b) of 1% by mass or more, it is possible to improve water-sealing properties and enhance the effect of reducing the amount of nonionic surfactant detected. By having a content of amine compound (b) of 30% by mass or less, it is possible to reduce the load on mixer bolts, etc., during construction.

[0049] In one embodiment, the content of primary amine (b1) (preferably primary diamine (b2), more preferably aliphatic primary diamine and / or aromatic primary diamine (b3)) in component (A) is preferably 1.0 to 15% by mass, and more preferably 2.0 to 10% by mass.

[0050] The amount of amine compound (b) per 100 parts by mass of polyol (a) is not particularly limited, and may be, for example, 5 to 55 parts by mass, 6 to 40 parts by mass, 7 to 20 parts by mass, or 8 to 15 parts by mass.

[0051] (Catalyst (c)) Component (A) contains a catalyst (c) to promote the reaction between the polyol (a) and the isocyanate. Examples of catalyst (c) include tertiary amine catalysts, fatty acid alkali metal salts, and quaternary ammonium salts. Among these, the use of a tertiary amine catalyst is preferred. In one embodiment, catalyst (c) may include a tertiary amine catalyst and a fatty acid alkali metal salt and / or a quaternary ammonium salt.

[0052] Examples of tertiary amine catalysts include triethylenediamine, 2-methyltriethylenediamine, N,N,N',N'-tetramethylhexamethylenediamine, N,N,N',N'-tetramethylpropylenediamine, N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-pentamethyldiethylenetriamine, trimethylaminoethylpiperazine, bis-(dimethylaminoethyl) ether, N,N',N''-tris(dialkylaminoalkyl)-s-hexahydrotriazine, N,N-dimethylaminoethylmorpholine, dimethylaminopropylimidazole, hexamethyltriethylenetetramine, hexamethyltripropylenetetramine, N,N,N-tris(3-dimethylaminopropyl)amine, etc., which can be used individually or in combination of two or more.

[0053] Examples of alkali metal salts of fatty acids include alkali metal salts of acetic acid or octic acid, which are used as trimerization catalysts. Here, the number of carbon atoms in the fatty acid constituting the alkali metal salt may be 1 to 10. Specific examples of alkali metal salts of fatty acids include potassium acetate and potassium octoate, and either one or both may be used in combination.

[0054] As quaternary ammonium salts, commercially available trimerization catalysts can be used, such as Kaolizer No. 410, Kaolizer No. 420 (manufactured by Kao Corporation), TOYOCAT-TR20, and TOYOCAT-TRX (manufactured by Tosoh Corporation).

[0055] The amount of catalyst (c) (preferably a tertiary amine catalyst) is not particularly limited, but is preferably 0.05 to 10% by mass, more preferably 0.1 to 8.0% by mass, more preferably 0.1 to 5.0% by mass, and even more preferably 0.1 to 3.0% by mass, based on 100% by mass of component (A).

[0056] (Flame retardant (d)) (A) Component (d) contains a flame retardant (d). This imparts flame retardancy to the cured product. The flame retardant (d) is not particularly limited and may be either an additive type or a reactive type. Preferably, an additive type flame retardant is used.

[0057] Specific examples of additive-type flame retardants include phosphate ester flame retardants such as trimethyl phosphate, triethyl phosphate, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate, tris(chloropropyl) phosphate, and tris(tribromoneopentyl) phosphate, as well as halogen-containing flame retardants such as chlorinated paraffin, pentabromoethylbenzene, and decabromodiphenyl ether. These can be used individually or in combination of two or more.

[0058] Specific examples of reactive flame retardants include dibromoneopentyl glycol, tetrabromobisphenol A, O,O-diethyl N,N-dihydroxyethylaminomethylphosphotate, and halogen-containing phosphorus compounds having hydroxyl groups or amino groups, such as various phosphorus-containing polyols.

[0059] Among these, it is preferable to use a phosphate ester-based flame retardant (d) as the flame retardant.

[0060] The amount of flame retardant (d) (preferably a phosphate ester flame retardant) is not particularly limited, and may be 5 to 50% by mass, 10 to 45% by mass, or 15 to 40% by mass, relative to 100% by mass of component (A).

[0061] (Other ingredients) In addition to the components described above, component (A) may optionally contain known additives such as foaming agents, silicone-based foam stabilizers, diluents, pigments, inorganic fillers, crosslinking agents, and coupling agents, to the extent that they do not impair the purpose of this embodiment.

[0062] Water is an example of a foaming agent. Water acts as a foaming agent because it reacts with the isocyanate of component (B) to generate carbon dioxide. When added, the amount of water is not particularly limited, but may be 0.2 to 5.0% by mass, 0.3 to 3.0% by mass, or 0.5 to 2.0% by mass, relative to 100% by mass of component (A). In one embodiment, it is preferable that component (A) is substantially water-free. Substantially water-free means that the amount of water is 1.0% by mass or less relative to 100% by mass of component (A), preferably 0.5% by mass or less, more preferably 0.3% by mass or less.

[0063] Examples of silicone-based foam stabilizers include polyoxyalkylene dimethylpolysiloxane copolymer, which is commonly used in rigid polyurethane foam resins.

[0064] Examples of diluents include phthalates such as dibutyl phthalate, dioctyl phthalate, and diisononyl phthalate; adipates such as dibutyl adipate, dioctyl adipate, diisononyl adipate, and bis(2-(2-butoxyethoxy)ethyl) adipate; and trimellitates such as tri(2-ethylhexyl) trimellitate.

[0065] [(B) Component] Component (B) is a component containing an isocyanate that reacts with the active hydrogen compound of component (A), and in this embodiment, it contains an aromatic polyisocyanate (B1).

[0066] (Aromatic polyisocyanate (B1)) Examples of aromatic polyisocyanates (B1) include diphenylmethane diisocyanate (MDI), polymethylene polyphenyl polyisocyanate (polymeric MDI), tolylene diisocyanate, xylylene diisocyanate, phenylene diisocyanate, naphthalene diisocyanate, and modified versions thereof. Any one of these may be used, or two or more may be used in combination. Examples of modified versions include isocyanurate modified versions, allophanate modified versions, biuret modified versions, adduct modified versions, carbodiimide modified versions, and dimers.

[0067] Among these, MDI-based polyisocyanates (B2) are preferred as aromatic polyisocyanates (B1). Specifically, aromatic polyisocyanates (B1) preferably include at least one MDI-based polyisocyanate (B2) selected from the group consisting of diphenylmethane diisocyanate (MDI), polymethylene polyphenyl polyisocyanate (polymeric MDI), and modified versions thereof.

[0068] The diphenylmethane diisocyanate may be any of 2,2'-MDI, 2,4'-MDI, or 4,4'-MDI, or any mixture thereof. The polymethylene polyphenyl polyisocyanate (polymeric MDI) is a polynuclear condensate of diphenylmethane diisocyanate, and may be a mixture of the polynuclear condensate and diphenylmethane diisocyanate (monomeric MDI).

[0069] The aromatic polyisocyanate (B1) preferably contains 50% by mass or more of the above-mentioned MDI-based polyisocyanate (B2) (more preferably polymethylene polyphenyl polyisocyanate), more preferably 70% by mass or more, even more preferably 90% by mass or more, and may even be 100% by mass.

[0070] Component (B) may include isocyanates other than aromatic polyisocyanate (B1), such as aliphatic polyisocyanates and / or alicyclic polyisocyanates. The isocyanate contained in component (B) is preferably mainly aromatic polyisocyanate (B1), more preferably containing 70% by mass or more of aromatic polyisocyanate (B1) per 100% by mass of isocyanate, more preferably 90% by mass or more, and may be 100% by mass.

[0071] (Other ingredients) Component (B) may consist solely of isocyanate. Component (B) may also contain, as necessary, conventionally known additives as described in section (A), to the extent that they do not impair the purpose of this embodiment.

[0072] [A mixture of component (A) and component (B)] Component (A) and component (B) are mixed at the time of use to form a cured product. The mixing ratio of component (A) and component (B) is not particularly limited, but the reaction equivalent ratio of the isocyanate group (NCO) in component (B) to the active hydrogen group of the active hydrogen compound in component (A), i.e., NCO / active hydrogen group, is preferably in the range of 1 / 5 to 5 / 1, more preferably 1 / 2 to 3 / 1, even more preferably 2 / 3 to 2 / 1, and may also be 1 / 1 to 5 / 3. By having the reaction equivalent ratio within the above range, a cured product with appropriate strength can be obtained with an appropriate curing time.

[0073] [Methods for consolidating natural ground] The ground consolidating agent according to this embodiment can be used, for example, to stabilize and strengthen rock mass with fractured zones or unstable soft ground during tunnel excavation. By mixing components (A) and (B) and injecting them into the rock mass or ground, the ground can be consolidated.

[0074] There are no particular limitations on the injection and solidification method, and known methods may be employed. For example, it is preferable to include the steps of drilling a plurality of holes in the rock or ground at predetermined intervals, inserting hollow bolts into the holes, and injecting the ground solidification agent into the rock or ground through the openings of the bolts to solidify it.

[0075] One example is to use a pump that can control the injection volume, pressure, and mixing ratio of components (A) and (B), and place components (A) and (B) into separate tanks. Perforated rock bolts or injection rods, which contain pre-fixed static mixers and check valves, are inserted into the tunnel face or top of the tunnel, where the sandy soil is difficult to penetrate. Components (A) and (B) from the tanks are injected into these at an injection pressure of 0.05 to 5 MPa, and the uniformly mixed components (A) and (B) permeate and harden into the ground through the static mixer. This allows the ground to be solidified and stabilized.

[0076] The ground consolidator composed of components (A) and (B) described above exhibits excellent hardening properties, enabling it to stop large amounts of water leakage and seepage. Therefore, the ground consolidator of this embodiment may be used for soil stabilization and strengthening, as well as for water stoppage. Furthermore, since the amount of nonionic surfactant detected under flowing water is reduced, the adverse effects on water quality can be minimized. [Examples]

[0077] The present invention will be described in more detail below based on examples and comparative examples. However, the present invention is not limited thereto.

[0078] <Raw materials used> [(A) component] (Polyol (a)) (a1): Ether-based polyols and their comparative raw materials: Tripropylene glycol: 2.0 functional groups, 584 mgKOH / g hydroxyl value • Dipropylene glycol: 2.0 functional groups, 836 mgKOH / g hydroxyl value PA-400: Aromatic polyether polyol, manufactured by Daiichi Kogyo Seiyaku Co., Ltd. as "Polyhardener PA-400", 2.0 functional groups, 420 mg KOH / g • Diethylene glycol: 2.0 functional groups, 1057 mgKOH / g G-480: Aliphatic polyether polyol, "DK Polyol G-480" manufactured by Daiichi Kogyo Seiyaku Co., Ltd., 3.0 functional groups, hydroxyl value 480 mgKOH / g (comparative raw material) • 420: Aliphatic polyether polyol, "Exenol 420" manufactured by AGC Inc., 2.0 functional groups, hydroxyl value 280 mg KOH / g (comparative raw material)

[0079] (a2): Polyester polyols and their comparable raw materials: • RFK-556: "Maximol RFK-556" manufactured by Air Water Performance Chemicals Inc. contains 95% by mass of an aromatic polyester polyol (2.0 functional groups, hydroxyl value 208 mgKOH / g) obtained from a polycarboxylic acid and a polyhydric alcohol, and 5% by mass of diethylene glycol as unreacted material. • RDK-133: "Maximol RDK-133" manufactured by Air Water Performance Chemicals Inc. contains 80% by mass of an aromatic polyester polyol (2.0 functional groups, hydroxyl value 130 mg KOH / g) obtained from a polycarboxylic acid and a polyhydric alcohol, and 20% by mass of diethylene glycol as unreacted material. • RDK-142: "Maximol RDK-142" manufactured by Air Water Performance Chemicals Inc. contains 70% by mass of an aromatic polyester polyol (2.0 functional groups, hydroxyl value 118 mg KOH / g) obtained from a polycarboxylic acid and a polyhydric alcohol, and 30% by mass of diethylene glycol as unreacted material. • Castor oil: "Castor Oil D" manufactured by Ito Oil Co., Ltd., 2.7 functional groups, 161 mgKOH / g hydroxyl value • H-81: "URIC H-81" manufactured by Ito Oil Co., Ltd., castor oil-based aliphatic polyester polyol, 3 functional groups, hydroxyl value 340 mgKOH / g • P-1010: Aliphatic polyester polyol, manufactured by Kuraray Co., Ltd., "Kuraray Polyol P-1010", 2.0 functional groups, 112 mg KOH / g • P-2010: Aliphatic polyester polyol, "Kuraray Polyol P-2010" manufactured by Kuraray Co., Ltd., 2.0 functional groups, hydroxyl value 56 mgKOH / g (comparative raw material)

[0080] Other polyols: Octanediol: 2-ethyl-1,3-hexanediol, manufactured by KH Neochem Co., Ltd., "Octanediol", 2.0 functional groups, 768 mg KOH / g

[0081] (Amine compound (b)) • Diethyltoluenediamine: "DETDA80" manufactured by Lonza Japan Co., Ltd., 2.0 functional groups, amine value 630 mgKOH / g • Polyetherdiamine: "Polyetheramine D-230" manufactured by Mitsui Chemicals Fine Co., Ltd., 2.0 functional groups, amine value 488 mgKOH / g • Secondary diamine: 4,4'-methylenebis[N-(1-methylpropyl)aniline], manufactured by Mitsui Chemicals Fine Co., Ltd., "EtaCure 420", 2.0 functional groups, amine value 361 mgKOH / g

[0082] (Catalyst (c)) • Tertiary amine catalyst: N,N,N-tris(3-dimethylaminopropyl)amine, EVONIK "Polycat 9" • Trimerization catalyst 1: "DABCO K15" manufactured by Evonik Japan Co., Ltd., containing 75% by mass of potassium octylate and 25% by mass of diethylene glycol. • Trimerization catalyst 2: Kao Corporation's "Kaolizer No. 420", quaternary ammonium salt

[0083] (Flame retardant) • TMCPP: Tris(chloropropyl) phosphate, manufactured by Daihachi Chemical Industry Co., Ltd. • TCP: Tricresyl phosphate, manufactured by Daihachi Chemical Industry Co., Ltd. ("TCP")

[0084] [Component (B)] (Isocyanate) · MR-200: Polymeric MDI, "Millionate MR-200" manufactured by Tosoh Corporation · MR-400: Polymeric MDI, "Millionate MR-400" manufactured by Tosoh Corporation · 376N: Isocyanurate-modified pentamethylene diisocyanate (PDI), "Stabio 376N" manufactured by Mitsui Chemicals, Inc.

[0085] [Preparation of Liquid A and Liquid B] A liquid composed of Component (A) was designated as Liquid A, and a liquid composed of Component (B) was designated as Liquid B. Liquid A and Liquid B were respectively prepared by appropriately mixing raw materials according to the formulations (parts by mass) described in Tables 1 to 6 below.

[0086] The parts by mass of each component in the table represent the amount used as a raw material. Therefore, the parts by mass in the table for "RFK-556," "RDK-133," and "RDK-142" represent the amount of these products, i.e., the total amount of polyester polyol and diethylene glycol contained in the product. On the other hand, the "mass ratio (a2) / (a1)" in the table represents the mass ratio of polyester polyol (a2) to ether polyol (a1) actually contained in liquid A. Therefore, in the examples and comparative examples using these products, the amount of polyester polyol (a2) is calculated by subtracting the amount of diethylene glycol from the amount of the product, and the amount of ether polyol (a1) is calculated by adding the amount of diethylene glycol that was subtracted, and then the value of (a2) / (a1) is calculated. For example, in Example 1, the amount of "RFK-556" is 29.0 parts by mass, of which 27.55 parts by mass is the amount of polyester polyol (a2) and the remaining 1.45 parts by mass is the amount of diethylene glycol. Therefore, the amount of ether polyol (a1) is 36.45 parts by mass, which is the sum of 35.0 parts by mass of tripropylene glycol and 1.45 parts by mass of ether polyol (a1). Thus, (a2) / (a1) is 27.55 / 36.45, which rounds to 0.8 when rounded to the second decimal place. The same applies to the mass ratios of "{(a1)+(a2)} / (a)×100", "(a1) / (a)×100", "(a2) / (a)×100", "(a1) / (A)×100", and "(a2) / (A)×100" in the table, and are calculated using the actual amounts of polyester polyol (a2) and ether polyol (a1) contained in solution A.

[0087] The mass portion in the table for "Trimerization Catalyst 1" also represents the amount of the product, which is the total amount of potassium octylate and diethylene glycol (the solvent) contained in the product. Therefore, for each mass ratio in the table, the amount of ether polyol (a1) is added to the amount of diethylene glycol contained in Trimerization Catalyst 1.

[0088] In the table, "Equivalent Ratio (NCO / Active Hydrogen Group)" represents the reaction equivalent ratio between the isocyanate group (NCO) in component (B) and the active hydrogen group of the active hydrogen compound in component (A).

[0089] <Rating> [Curing time, expansion ratio] Liquids A and B, at a liquid temperature of 20°C, were mixed by hand mixing, and the curing time (time when curing progresses and stringing begins) without a foaming agent, or the curing time (time from the start of stirring until foaming is complete) with a foaming agent was measured. After the curing reaction was complete, the foaming ratio was calculated by dividing the volume of the cured product by the initial volumes of the raw materials, liquids A and B.

[0090] [Amount of nonionic surfactant detected] 900g of 20°C water was poured into a 2L plastic cup, and the water was stirred with a mixer to recreate a flowing water state. 60g of solution A and 60g of solution B were hand-mixed at 20°C, and the mixture was added to the flowing water. After the mixture hardened, the flowing water was collected, and the amount of nonionic surfactant detected was measured in accordance with the solid-phase extraction-absorbance spectrophotometric method specified in Appendix 28 of the Water Supply Act. A detection level of less than 1 mg / L was rated as "A," a level between 1 mg / L and 10 mg / L was rated as "B," and a level of 10 mg / L or more was rated as "C."

[0091] [Waterproofing] Crushed stone was packed into an acrylic cylinder (inner diameter / outer diameter = φ44mm / φ48mm, length = 300mm), and water was flowed through one side of the cylinder at a rate of 2L / min to simulate natural ground. A hole was made in the middle of the cylinder, and 50mL of a mixture of liquids A and B was injected into the simulated ground using a syringe. After injection, the water stoppage and the length of the resin filling were checked. We evaluated the results as follows: "A" if water could be stopped and the filling length was 100 mm or less; "B" if water could be stopped and the filling length was more than 100 mm but 200 mm or less; and "C" if water could not be stopped.

[0092] [Suitability for ground improvement] A sand gel (φ50mm x height 100mm) was prepared by mixing liquid A, liquid B, and No. 7 silica sand in a 50 / 50 / 30 (mass ratio) to simulate the state of ground solidified with chemicals. The sand gel was compressed according to JIS K 7220:2006 "Rigid foamed plastics - Method for determining compression". The sand gel did not rupture during compression and its compressive strength was 20 N / mm². 2 In the above cases, it is designated as "A", with no fracture and 10 N / mm 2 Super 20N / mm 2 If less than 10 N / mm², it is designated as "B". If fracture is present or 10 N / mm² is 10 N / mm². 2 The following cases were evaluated as "C".

[0093] [Table 1]

[0094] [Table 2]

[0095] [Table 3]

[0096] [Table 4]

[0097] [Table 5]

[0098] [Table 6]

[0099] The results are shown in Tables 1 to 6. Comparative Example 1 used an ether polyol with 3.0 functional groups, and a large amount of nonionic surfactant was detected. Comparative Example 2 used an ether polyol with a hydroxyl value lower than the set value, and exhibited poor water-sealing and ground-improving properties, as well as a large amount of nonionic surfactant. Comparative Example 3 used a polyester polyol with a hydroxyl value lower than the set value, and exhibited poor water-sealing and ground-improving properties.

[0100] Comparative Example 4 was an example that did not contain an ether-based polyol and exhibited inferior water-sealing properties and ground-improving properties. Comparative Example 5 was an example that did not contain a polyester polyol and exhibited inferior ground-improving properties. Comparative Example 6 was an example in which an ether-based polyol with a low hydroxyl value was added instead of polyester polyol (a2). Compared to Comparative Example 5, ground-improving properties were improved, but the amount of nonionic surfactant detected increased.

[0101] Comparative Examples 7 and 8 had low amounts of ether polyol (a1) in the ether polyol and high levels of nonionic surfactant. Comparative Example 9 was an example that did not contain amine compound (b) as a modifier, and had poor water-sealing properties and high levels of nonionic surfactant. Comparative Example 10 used aliphatic polyisocyanate instead of aromatic polyisocyanate, and had poor water-sealing properties and ground improvement properties, as well as high levels of nonionic surfactant.

[0102] In contrast, Examples 1 to 27 of this embodiment, which use ether polyol (a1) and polyester polyol (a2), showed low levels of nonionic surfactant detection, good water-sealing and ground-improving properties, and excellent performance as a ground-consolidating agent. Here, Examples 1 to 4 use ether polyol (a1) with different hydroxyl values, Examples 5 to 9 use polyester polyol (a2) with different hydroxyl values ​​or different types (aromatic and aliphatic), and Examples 10 to 12 change the blending amounts of (a1) and (a2). In Example 13, the type of amine compound (b), which is a modifier, is changed, and in Examples 14 to 16, the blending amount and type of amine compound (b) are changed. In Example 17, the type of flame retardant (d) is changed, in Example 18, water is added as a blowing agent, and in Example 19, the type of isocyanate is changed. In Examples 20 and 21, other polyols are used in combination with ether polyol (a1) and polyester polyol (a2). In Examples 22, 23, and 25-27, a tertiary amine catalyst is used in combination with a fatty acid alkali metal salt or a quaternary ammonium salt as catalyst (c).

[0103] Furthermore, the various numerical ranges described in this specification can be any combination of their upper and lower limits, and all such combinations are described herein as preferred numerical ranges. Also, the description of a numerical range as "X~Y" means X or greater and Y or less.

[0104] Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their omissions, substitutions, and modifications are included in the scope and spirit of the invention, as well as in the claims and their equivalents.

Claims

1. Component (A) comprises a polyol (a), an amine compound having a primary amino group and / or a secondary amino group (b), a catalyst (c), and a flame retardant (d), The material comprises component (B) containing an aromatic polyisocyanate, The polyol (a) comprises an ether-based polyol (a1) having 1.5 to 2.5 functional groups and a hydroxyl value of 400 to 1100 mgKOH / g, and a polyester polyol (a2) having a hydroxyl value of 100 to 400 mgKOH / g. 90% by mass or more of the ether-based polyol contained in the polyol (a) is the ether-based polyol (a1), The total amount of the ether-based polyol (a1) and the polyester polyol (a2) in the polyol (a) is 50% by mass or more. Ground consolidation agent.

2. The ground consolidator according to claim 1, wherein the content of the ether-based polyol (a1) in the polyol (a) is 5 to 95% by mass, and the content of the polyester polyol (a2) in the polyol (a) is 5 to 95% by mass.

3. The ground consolidator according to claim 1, wherein the content of the amine compound (b) in component (A) is 1 to 30% by mass.

4. The ground consolidator according to claim 1, wherein the aromatic polyisocyanate comprises at least one selected from the group consisting of diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, and modified forms thereof.

5. A process of drilling multiple holes at predetermined intervals in bedrock or ground. The steps include inserting a hollow bolt into the aforementioned hole, and A step of injecting the ground consolidator described in any one of claims 1 to 4 into the rock or ground through the opening of the bolt and consolidating it. Methods for consolidating natural ground, including those mentioned above.

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