Natural ground solidifying agent and natural ground solidifying method using same

Abstract

The present invention exhibits less amount of a nonionic surfactant detected when being placed in flowing water and has excellent performance as a natural ground solidifying agent. This natural ground solidifying agent comprises: (A) a component including polyols (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 (B) a component including an aromatic polyisocyanate. The polyols (a) include an ether-based polyol (a1) that has 1.5-2.5 functional groups and that has a hydroxyl value of 400-1100 mgKOH / g, and a polyester polyol (a2) that has a hydroxyl value of 100-400 mgKOH / g. 90 mass% or more of ether-based polyols included in the polyols (a) is the ether-based polyol (a1). The total amount of the ether-based polyol (a1) and the polyester polyol (a2) in the polyols (a) is 50 mass% or more.

Description

Ground consolidation agent and method for consolidating ground using the same

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

[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.

[0004] Japanese Patent No. 5851481

[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 as a ground consolidation agent while reducing the detected amount of nonionic surfactants.

[0006] In view of the above points, an embodiment of the present invention aims to provide a ground consolidation agent with a small detected amount of nonionic surfactant and excellent performance as a ground consolidation agent, and a method for consolidating ground using the same.

[0007] The present invention includes the embodiments shown below. [1] A ground consolidator comprising: component (A) comprising 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); and component (B) comprising an aromatic polyisocyanate, wherein the polyol (a) comprises 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, wherein 90% by mass or more of the ether polyol contained in the polyol (a) is the ether polyol (a1), and the total amount of the ether 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 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 the 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.

[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.

[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 ground consolidator, in which component (A) is liquid A and component (B) is liquid B. In addition to components (A) and (B), a third component may be included as an optional component.

[0011] [Component (A)] Component (A) 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, such as a hydroxyl group or a primary amino group (-NH). ２ Examples include secondary amino groups (-NHR).

[0012] (Polyol (a)) Component (A) contains polyol (a) as an active hydrogen compound. Polyol (a) comprises 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, 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, by having 1.5 or more functional groups in the ether polyol (a1), the strength after curing can be increased, thereby improving the performance of the ground consolidator. By having 2.5 or less functional groups in the ether polyol (a1), the amount of nonionic surfactant detected can be reduced. Furthermore, by having a hydroxyl value of 400 mgKOH or more in the ether polyol (a1), the strength after curing can be increased, improving the performance of the ground consolidator, and the amount of nonionic surfactant detected can also be reduced.

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

[0018] The ether polyol (a1) may be an aliphatic ether polyol, an aromatic ether polyol, or a combination of both. An aliphatic ether polyol is an ether polyol that does not contain an aromatic ring in its molecule. An aromatic ether polyol is an ether polyol that contains an aromatic ring in its molecule.

[0019] Examples of aliphatic ether polyols include aliphatic polyether polyols obtained by addition polymerization using known methods with 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, or aliphatic active hydrogen compounds such as monoethanolamine, diethanolamine, and ethylenediamine, using one or more alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide. Other examples of aliphatic ether polyols include diethylene glycol, triethylene glycol, dipropylene glycol, and tripropylene glycol. These aliphatic ether polyols may be used individually or in combination of two or more.

[0020] Examples of aromatic ether polyols include aromatic polyether polyols obtained by addition polymerization using known methods with aromatic active hydrogen compounds such as aniline, benzenediol, and bisphenol compounds, and one or more alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide. Aromatic ether polyols may also be obtained by using only one or more of these oxides in combination.

[0021] Polyol (a) may contain ether polyols other than the above-mentioned ether polyol (a1), but if it does contain other ether polyols, the amount is preferably small. Specifically, in this embodiment, 90% by mass or more of the ether polyol contained in polyol (a) is ether polyol (a1). That is, the content of ether polyol (a1) in 100% by mass of ether polyol contained in polyol (a) is 90% by mass or more, preferably 95% by mass or more, and more preferably 100% by mass. In other words, the ether polyol may consist only of ether polyol (a1). This makes it possible to reduce the amount of nonionic surfactant detected under running water.

[0022] Polyol (a) includes the above-mentioned ether-based polyol (a1) along with a polyester polyol (a2) having a hydroxyl value of 100 to 400 mg KOH / g. By using a polyester polyol with a relatively low hydroxyl value in combination in this way, it is possible to improve the performance of the ground consolidator while reducing the amount of nonionic surfactant detected.

[0023] In detail, a hydroxyl value of 100 mg KOH / 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 mg KOH / 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 mg KOH / g or less, more preferably 150 to 300 mg KOH / g, and even more preferably 150 to 250 mg KOH / g. In one embodiment, the hydroxyl value of the polyester polyol may be 100 to 250 mg KOH / g, or 100 to 161 mg KOH / 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 aromatic rings in their molecule. Aromatic polyester polyols are polyester polyols that contain aromatic rings 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 an aliphatic polyester polyol 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 an aromatic polyester polyol 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 even 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 even 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 even 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 a primary and a secondary amino group. 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 the alicyclic diamine include 4,4'-diaminocyclohexylmethane, isophoronediamine, bisaminomethylcyclohexane, 2,5- or 2,6-diaminomethylbicyclo[2,2,1]heptane, diaminocyclohexane, and the like.

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

[0044] Examples of the aliphatic triamine include diethylenetriamine, polyether triamine, and the like. Here, the polyether triamine is a compound obtained by converting the hydroxyl groups of polyoxyalkylene triols obtained by addition polymerization of propylene oxide and / or ethylene oxide to glycerin or trimethylolpropane into primary amino groups, and is also referred to as polyoxyalkylene triamine.

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

[0046] Any one of these amine compounds (b) may be used, or two or more thereof may be used in combination.

[0047] In one embodiment, the amine compound (b) preferably contains a primary amine (b1) having a primary amino group, more preferably contains a primary diamine (b2), and still more preferably contains 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 still 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 for 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)) Component (A) 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-based 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, based on 100% by mass of component (A).

[0061] (Other components) In addition to the components described above, components (A) may include, as necessary, 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 free of water. Substantially free of water 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, and 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] [Component (B)] 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 polyisocyanates (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 components) Component (B) may consist only 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] [Mixing 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 in an appropriate curing time.

[0073] [Method for Consolidating 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. The ground can be consolidated by mixing component (A) and component (B) and injecting it into the rock mass or ground.

[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) through the static mixer permeate and harden into the ground. 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.

[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) Components] (Polyol (a)) ・(a1): Ether-based polyol and its comparative raw materials: ・Tripropylene glycol: 2.0 functional groups, hydroxyl value 584 mg KOH / g ・Dipropylene glycol: 2.0 functional groups, hydroxyl value 836 mg KOH / g ・PA-400: Aromatic polyether polyol, "Polyhardener PA-400" manufactured by Daiichi Kogyo Seiyaku Co., Ltd., 2.0 functional groups, hydroxyl value 420 mg KOH / g ・Diethylene glycol: 2.0 functional groups, hydroxyl value 1057 mg KOH / g ・G-480: Aliphatic polyether polyol, "DK Polyol G-480" manufactured by Daiichi Kogyo Seiyaku Co., Ltd., 3.0 functional groups, hydroxyl value 480 mg KOH / 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 comparative 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 mg KOH / 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 mg KOH / g - H-81: "URIC H-81" manufactured by Ito Oil Co., Ltd., castor oil-based aliphatic polyester polyol, 3 functional groups, 340 mg KOH / g - P-1010: Aliphatic polyester polyol, "Kuraray Polyol P-1010" manufactured by Kuraray Co., Ltd., 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, 56 mg KOH / 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 hydroxyl value

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

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

[0083] (Flame retardants) ・TMCP: Tris(chloropropyl) phosphate, manufactured by Daihachi Chemical Industry Co., Ltd. as "TMCP" ・TCP: Tricresyl phosphate, manufactured by Daihachi Chemical Industry Co., Ltd. as "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 form of pentamethylene diisocyanate (PDI), "Stavio 376N" manufactured by Mitsui Chemicals, Inc.

[0085] <Preparation of Solution A and Solution B> Solution A was prepared by mixing the raw materials appropriately according to the proportions (parts by mass) listed in Tables 1 to 6 below, with the liquid consisting of component (A) being designated as Solution A and the liquid consisting of component (B) being designated as Solution B.

[0086] The mass portion of each component in the table represents the amount used as a raw material. Therefore, the mass portion in the table for "RFK-556," "RDK-133," and "RDK-142" represents 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" blended 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. 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-based polyol (a1) contained in liquid 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] The "Equivalent Ratio (NCO / Active Hydrogen Group)" in the table 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] <Evaluation> [Curing time, foaming ratio] Liquids A and B, with 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 completed) 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] [Detection of Nonionic Surfactants] 900g of 20°C water was poured into a 2L poly cup, and the water was stirred with a mixer to recreate a flowing water state. 60g of Solution A and 60g of Solution B at 20°C were hand-mixed, 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 amount of less than 1 mg / L was evaluated as "A", an amount of 1 mg / L or more but less than 10 mg / L was evaluated as "B", and an amount of 10 mg / L or more was evaluated as "C".

[0091] [Water-stopping properties] Crushed stone was packed into an acrylic cylinder (inner diameter / outer diameter = φ44 mm / φ48 mm, length = 300 mm), and water was flowed through one side of the cylinder at a rate of 2 L / min to simulate natural ground. A hole was made in the middle of the cylinder, and 50 mL of a mixture of liquids A and B was injected into the simulated ground using a syringe. After injection, the ability to stop the water flow and the length of the resin filling were checked. If the water could be stopped and the filling length was 100 mm or less, it was evaluated as "A"; if the water could be stopped and the filling length was between 100 mm and 200 mm, it was evaluated as "B"; and if the water could not be stopped, it was evaluated as "C".

[0092] [Ground Improvement Capabilities] A sand gel (φ50 mm x height 100 mm) was prepared by mixing liquid A, liquid B, and No. 7 silica sand in a 50 / 50 / 30 (mass ratio) to reproduce the state of ground solidified with chemical solutions. The sand gel was compressed in accordance with JIS K 7220:2006 "Rigid foamed plastics - Method for determining compression strength". The sand gel did not rupture during compression and its compressive strength was 20 N / mm². ２ In the above case, it is "A", no breakage and 10 N / mm ２ Super 20N / mm ２ If less than 10 N / mm, it is designated as "B". If fracture is present or 10 N / mm ２ The following cases were rated as "C".

[0093]

[0094]

[0095]

[0096]

[0097]

[0098]

[0099] The results are shown in Tables 1 to 6. Comparative Example 1 used an ether-based polyol with 3.0 functional groups, and a large amount of nonionic surfactant was detected. Comparative Example 2 used an ether-based 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 was inferior in water-sealing properties and ground improvement properties. Comparative Example 5 was an example that did not contain a polyester polyol and was inferior in ground improvement 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 improvement 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 the amine compound (b) as a modifier, and exhibited poor water-sealing properties and high levels of nonionic surfactant. Comparative Example 10 used an aliphatic polyisocyanate instead of an aromatic polyisocyanate, and exhibited 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 an alkali metal fatty acid 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 to 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. A ground consolidating agent comprising: Component (A) comprising 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); and Component (B) comprising an aromatic polyisocyanate, wherein the polyol (a) comprises 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, wherein 90% by mass or more of the ether polyol contained in the polyol (a) is the ether polyol (a1), and the total amount of the ether polyol (a1) and the polyester polyol (a2) in the polyol (a) is 50% by mass or more.

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 method for solidifying a rock mass or ground, comprising the steps of drilling a plurality of holes at predetermined intervals in the rock mass or ground, inserting hollow bolts into the holes, and injecting a ground solidifying agent described in any one of claims 1 to 4 into the rock mass or ground through the opening of the bolts to solidify it.

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