JP2021042088A - Quick setting admixture, quick setting admixture solution, chemical solution for soil stabilization, manufacturing method of chemical solution thereof, and ground stabilization method - Google Patents

Abstract

To provide a quick setting admixture, a quick setting admixture solution and a chemical solution for soil stabilization, which have a short gel time and an excellent flash-setting property, and a manufacturing method of the chemical solution thereof, and a ground stabilization method.SOLUTION: The present inventions discloses: a quick setting admixture used by mixing to a main material solution so that the main material solution containing lime and water sets, and containing dry aluminum hydroxide gel and alkali metal carbonate, or amorphous aluminum hydroxide and alkali metal carbonate, and alkali metal hydroxide and/or alkali metal silicate; a quick setting admixture solution containing the quick setting admixture; and a ground stabilization method in which the main material solution containing lime and water, and the quick setting admixture are mixed in ground.SELECTED DRAWING: None

Description

The present invention relates to a curing material, a curing material solution, a soil stabilizing chemical solution, a method for producing the chemical solution, and a ground stabilizing method.

As a soil stabilizing chemical solution used to reinforce the ground by injecting it into the ground, a cement suspension in which cement is suspended in water is used, but the cement suspension has a slow coagulation rate and until it condenses. It takes several hours. If the condensation rate is slow, the cement in the cement suspension will settle and the entire cement will not be able to harden.
In addition, when the injected cement suspension comes into contact with running water, such as in the ground where groundwater is flowing or in the gap between the embankment and the ground, if the coagulation rate is slow, the cement suspension Is mixed with running water to reduce the concentration of cement, so that the cement does not harden sufficiently.
Therefore, when the cement suspension is used as a chemical solution for soil stabilization, the cement suspension secures fluidity before being injected into the ground, gels in about 10 seconds after injection, and develops strength at an early stage. Is required to do.

Therefore, recently, a curing material solution for improving the curing rate of a cement suspension has been used.
For example, in Patent Document 1, slaked lime or quicklime is used as liquid A, and amorphous aluminum hydroxide, specifically, aluminum sludge dry powder (aluminum sludge generated by alumite treatment is dried, and aluminum hydroxide is amorphous. , And the solution A or solution B is mixed with anhydrous slaked steel, and the solution B is further mixed with an alkali metal carbonate accelerator, and solution A and solution B are used. A two-shot type injection material obtained by mixing and is disclosed, and according to this injection material, the time (gel time) from the completion of mixing the liquid A and the liquid B to gelation can be set to about 10 seconds. It is said that it is possible.

JP-A-2010-53023

However, in the case of ground where groundwater is flowing, there is a problem of further shortening the gel time. Further, when amorphous aluminum hydroxide is used, there is a problem that the gel time becomes long at a low temperature.

Therefore, an object of the present invention is to provide a curing material, a curing material solution, a soil stabilizing chemical solution, a method for producing the chemical solution, and a ground stabilizing method, which are excellent in instantaneous connection and can further shorten the gel time. ..
Another object of the present invention is to provide a curing material, a curing material solution, a chemical solution for soil stabilization, a method for producing the chemical solution, and a ground stabilization method capable of shortening the gel time even at a low temperature.

The present invention includes the following aspects [1] to [6].
[1] A curing material used by mixing with the main material liquid for curing a main material liquid containing lime and water, which is characterized by containing a dry aluminum hydroxide gel and an alkali metal carbonate. ..
[2] A curing material used by mixing with the main material liquid to cure the main material liquid containing lime and water, which is an amorphous aluminum hydroxide, an alkali metal carbonate, an alkali metal hydroxide, and the like. A curing material comprising and / or an alkali metal silicate.
[3] A curing material liquid containing the curing material and water according to [1] or [2].
[4] A chemical solution for stabilizing soil, which comprises the curing material according to [1] or [2], lime and water.
[5] A method for producing a soil stabilizing chemical solution, which comprises mixing a main material solution containing lime and water with the curing material solution according to [3].
[6] A ground stabilization method characterized by mixing a main material liquid containing lime and water with the curing material liquid according to [3] in the ground.

According to the present invention, it is possible to provide a curing material, a curing material solution, a chemical solution for soil stabilization, a method for producing the chemical solution, and a ground stabilization method, which are excellent in instantaneous connection and can further shorten the gel time. .. Further, it is possible to provide a curing material, a curing material solution, a soil stabilizing chemical solution, a method for producing the chemical solution, and a ground stabilizing method capable of shortening the gel time even at a low temperature.

Hereinafter, the present invention will be described in detail.
As used herein, the term "consolidated body" means that the chemical solution for stabilizing soil of the present invention is condensed in the ground.

[Curing material]
The curing material of the present invention is used by mixing with the main material liquid to cure the main material liquid containing lime and water. The cured material of the present invention contains a dry aluminum hydroxide gel and an alkali metal carbonate. Alternatively, the cured material of the present invention contains amorphous aluminum hydroxide and alkali metal carbonate, and alkali metal hydroxide and / or alkali metal silicate.
Further, the curing material of the present invention may contain other additives other than the above.
Hereinafter, each component contained in the curing material of the present invention will be described.

(Dry aluminum hydroxide gel)
In the present invention, the dry aluminum hydroxide gel is _{a compound having a chemical composition of Al (OH) 3} mH ₂ O, and is amorphous aluminum hydroxide. Examples of the dry aluminum hydroxide gel include those used for medical antacids and ulcer healing agents of the Japanese Pharmacy, but for industrial use, dry aluminum hydroxide gel used as an adsorbent and the like is preferable. The aluminum oxide content of the dry aluminum hydroxide gel is preferably 45% or more, more preferably 50% or more.
The particle size of the dried aluminum hydroxide gel is preferably 40 to 120 μm, more preferably 60 to 100 μm, in terms of the median diameter obtained by the laser diffraction / scattering method. When the median diameter is at least the above lower limit value, the particles are hard to fly and the handleability is improved. On the other hand, when it is equal to or less than the above upper limit value, the reactivity is high and the expression of instantaneous confusion is excellent.

(Amorphous aluminum hydroxide)
Amorphous aluminum hydroxide includes all amorphous aluminum hydroxide. Examples of amorphous aluminum hydroxide include the dry aluminum hydroxide gel, and examples thereof include aluminum sludge generated by alumite treatment.
The dry aluminum hydroxide gel is included in the amorphous aluminum hydroxide, but the dry aluminum hydroxide gel is amorphized in a more reactive state among the amorphous aluminum hydroxide. It is distinguished from aluminum sludge and the like used in Patent Document 1.

(Alkali metal carbonate)
Alkali metal carbonate is a component that adds instantaneousness in the combination of lime having a gelling ability and dry aluminum hydroxide gel or amorphous aluminum hydroxide. Alkali metal carbonate destabilizes the main material liquid when blended with the main material liquid, but does not destabilize the cured material liquid when blended with the curing material liquid.

Examples of the alkali metal carbonate include alkali metal carbonates such as Li ₂ CO ₃ , Na ₂ CO ₃ , and K ₂ CO ₃ . The alkali metal carbonate may contain only one kind, or may contain two or more kinds in combination.

(Alkali metal hydroxide)
Examples of the alkali metal hydroxide include LiOH, NaOH, KOH and the like. The alkali metal hydroxide may contain only one kind, or may contain two or more kinds in combination.

(Alkali metal silicate)
Examples of the alkali metal silicate include lithium silicate, sodium silicate, potassium silicate and the like. The alkali metal silicate may contain only one kind, or may contain two or more kinds in combination.

Examples of the alkali metal silicate include alkali metal ortho silicate, alkali metal sesqui silicate, alkali metal meta silicate, alkali metal No. 1 silicate, alkali metal No. 2 silicate, alkali metal No. 3 silicate, and alkali metal No. 4. Examples thereof include aqueous silicate products, granular products, and powder products. Among them, an alkali metal orthosilicate having a high alkalinity is preferable, and sodium orthosilicate is more preferable, because it has a high effect of enhancing the ability to add instantaneousness.

(Additive)
In addition to amorphous aluminum hydroxide (including dry aluminum hydroxide gel), alkali metal carbonate, alkali metal hydroxide, and alkali metal silicate, the curing material of the present invention includes a water reducing agent, a defoaming agent, and a thickening agent. It may contain various additives such as agents.

Examples of the water reducing agent include lignin sulfonates or derivatives thereof, polycarboxylic acids, aminosulfonic acids, oxyorganic acids, alkylallyl sulfonates, polyoxyethylene alkyl ethers, polyol composites, and higher grades. Various water-reducing agents, dispersants, high-performance water-reducing agents mainly composed of valent alcohol sulfonate-based, melamine-formalin condensate-based (sulfonate, (modified) methylol), naphthalin-sulfonate-formal condensate-based Examples include fluidizing agents.

Defoamers include higher alcohols, alkylphenols, diethylene glycols, dibutylphthalates, water-insoluble alcohols, tributyl phosphates, polyglycols, silicones, ethylene oxide-propylene oxide copolymers, etc. Agents can be mentioned.

Thickeners include cellulose ethers such as methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxyethyl methyl cellulose, hydroxybutyl methyl cellulose, hydroxyethyl ethyl cellulose, carboxymethyl cellulose; polyacrylamide, sodium polyacrylate, polyacrylamide-polyacrylic. Acrylic polymers such as sodium acid copolymers and partial hydrolyzates of polyacrylamide; various thickeners such as water-soluble polymers such as polyvinyl alcohol, polyethylene oxide, sodium alginate, casein and guagam can be mentioned.

Further, in the cured material of the present invention, in order to improve the stability of the cured material and to adjust the gel time, various setting retarders such as organic carboxylic acids such as gluconic acid and citric acid and salts thereof are used. Can also be added.

(Manufacturing method of hardened material)
The cured material of the present invention may be a single material of each raw material put into water at the site, or may be mixed in a powder state in advance, but amorphous aluminum hydroxide (dry hydroxide) may be used. (Including aluminum gel) and alkaline carbonate should be mixed in advance in powder form. By blending these, it is possible to prevent the alkali metal carbonate from solidifying. The alkali metal hydroxide and the alkali metal silicate may be mixed in advance, or may be mixed in separate forms so as to be appropriately added according to the site environment.

The powder can be mixed by mixing each component in a desired blending amount with a commonly used mixer. The mixer used may be fixed to a factory or a construction site, or may be mounted on a mixer truck.
It is preferable that each component is sufficiently mixed. When each component is sufficiently mixed, a homogeneous curing material liquid can be quickly produced.

The contents of amorphous aluminum hydroxide (including dry aluminum hydroxide gel), alkali metal carbonate, alkali metal hydroxide and / or alkali metal silicate contained in the cured material of the present invention will be described later. The ratio may be such that the suitable composition of each component of the curing material liquid of the present invention is satisfied.

[Main material liquid]
The main material liquid according to the present invention contains lime and water. The main material liquid may contain other additives in addition to lime and water.
For example, hydraulic cement, gypsum, sodium sulfate, and potassium sulfate are preferably contained in the main material liquid from the viewpoint of improving the strength of the initial and final consolidated bodies.

Hereinafter, each component contained in the main material liquid will be described. The details of the other additives are the same as those of the above-mentioned other additives in the curing material of the present invention.

(lime)
Lime takes the form of calcium hydroxide (Ca (OH) ₂ ) in water, and examples thereof include slaked lime (Ca (OH) ₂ ) and quicklime (CaO). Of these, slaked lime, which is easy to handle, is preferable.

Blaine value of lime is preferably ^{6000~20000cm 2 / g, 8000~15000cm 2 /} g is more preferable. When the brain value of lime is equal to or higher than the above lower limit value, it is more excellent in instantaneous connection. On the other hand, if it is not more than the above upper limit value, the viscosity of the main material liquid is lowered, and aggregation is less likely to occur when mixed with water.
Lime may contain only one kind, or may contain two or more kinds in combination.

The content of lime in the main material liquid according to the present invention is preferably 10 to 50 kg, more preferably 20 to 40 kg, per 200 L of the main material liquid (400 L of the total chemical liquid). When the lime content is equal to or higher than the above lower limit value, it is more excellent in instantaneous connection. If it is not more than the above upper limit value, the viscosity of the main material liquid is suppressed, so that pumping is facilitated, and the main material liquid or the soil stabilizing chemical liquid described later easily permeates the ground. Further, if it is not more than the above upper limit value, the volume of the consolidated body with respect to the amount of the component in the main material liquid can be further increased.

(Hydraulic cement)
The content of the hydraulic cement in the main material liquid according to the present invention is not essential, but it is preferably contained from the viewpoint of increasing the initial and final strength of the consolidated body.
Examples of the water-hard cement include Portland cement such as ordinary, early-strength, ultra-fast-strength, moderate heat and white, mixed cement such as blast furnace cement, silica cement and fly ash cement, fine particle cement, ultrafine cement and ultrafine cement. Examples include fine cement, blast furnace granulated slag, and alumina cement. Since it exhibits hydraulicity due to the presence of lime, pozzolan-reactive substances are also included as hydraulic cement. Examples of the pozzolan-reactive substance include silica fume, fly ash, and active kaolin.
The hydraulic cement may contain only one kind, or may contain two or more kinds in combination.

When the main material liquid according to the present invention contains hydraulic cement, the content of the hydraulic cement in the main material liquid is preferably 25 to 300 kg per 200 L of the main material liquid (total chemical liquid 400 L), preferably 50 to 200 kg. More preferably, 70 to 150 kg is particularly preferable. When the content of the hydraulic cement is at least the above lower limit value, the compressive strength of the consolidated body can be further increased. On the other hand, if it is not more than the above upper limit value, the viscosity of the main material liquid is suppressed, so that pumping becomes easy, and the main material liquid or the soil stabilizing chemical liquid described later easily permeates the ground. Further, if it is not more than the above upper limit value, the volume of the consolidated body with respect to the amount of the component in the main material liquid can be further increased.

(plaster)
The main material liquid according to the present invention does not necessarily contain gypsum, but it is preferably contained from the viewpoint of increasing the initial and final strength of the consolidated body.
Examples of gypsum include various forms of gypsum such as type II anhydrous gypsum, type III anhydrous gypsum, α-hemihydrate gypsum, β-hemihydrate gypsum, and dihydrate gypsum. Among them, type II anhydrous gypsum is preferable because the compressive strength of the solidified body becomes higher. Further, as a source of sulfate ions contained in gypsum, sulfates such as sodium sulfate, potassium sulfate and aluminum sulfate can be added.

Blaine value of gypsum is preferably from ^{2500~15000cm 2 / g, 6000~10000cm 2 /} g is more preferable. When the gypsum brain value is equal to or higher than the above lower limit value, the compressive strength of the solidified body becomes higher. On the other hand, if it is not more than the above upper limit value, the viscosity of the main material liquid is lowered, and aggregation is less likely to occur when mixed with water.
The gypsum may contain only one type, or may contain a combination of two or more types.

When the main material liquid according to the present invention contains gypsum, the content of gypsum in the main material liquid is preferably 1 to 20 kg, more preferably 3 to 10 kg per 200 L of the main material liquid (400 L of the total chemical liquid). When the lime content is equal to or higher than the above lower limit, the initial and final strength of the consolidated body is high. If it is not more than the above upper limit value, the viscosity of the main material liquid is suppressed, so that pumping is facilitated, and the main material liquid or the soil stabilizing chemical liquid described later easily permeates the ground. Further, if it is not more than the above upper limit value, the volume of the consolidated body with respect to the amount of the component in the main material liquid can be further increased.

(Ratio of gypsum and lime)
When the main material liquid according to the present invention contains lime and gypsum, the mass ratio of gypsum (G) and lime (L) in the main material liquid is the value of the gypsum ratio "G / (G + L)", which is 0. 05 to 0.85 is preferable, and 0.1 to 0.4 is more preferable. When "G / (G + L)" is at least the above lower limit value, the compressive strength of the solidified body becomes higher. On the other hand, if it is not more than the above upper limit value, it is more excellent in instantaneous connection. Further, if it is not more than the above upper limit value, the volume of the consolidated body with respect to the amount of components in the main material liquid can be further increased.

(water)
Examples of water include clean water, industrial water, groundwater, river water, seawater and the like. Among these, clean water and industrial water are preferable in order to fully exert the effects of the present invention.

(Manufacturing method of main material liquid)
The main material liquid according to the present invention is produced by dispersing each component in water in a desired blending amount using a known stirrer or the like.
The order in which lime and water, hydraulic cement, gypsum, and other additives to be blended, if necessary, are mixed in the production of the main material liquid is not particularly limited. The method for producing the main material liquid is to disperse lime, gypsum to be blended as necessary, and additives such as dispersants and defoamers, which are optional components, in water, and then add hydraulic cement as needed. , A method of stirring and mixing for a predetermined time is preferable.

Examples of the method for producing the main material liquid at the construction site where the ground is stabilized include the following methods (1) to (3).
(1) A method in which lime, hydraulic cement to be blended as needed, and gypsum are separately carried to the construction site, mixed in a predetermined amount ratio, and then water is added and mixed. (2) Lime, if necessary A method in which a mixture of the main material, which is pre-blended with hydraulic cement and gypsum in a predetermined amount ratio, is brought to the construction site, and water is added to the mixture to mix (3) A material other than hydraulic cement is specified. Among the methods of bringing a mixture premixed in a quantity ratio together with hydraulic cement to the construction site and adding water to the mixture to mix, the work at the construction site can be simplified, so the above (2) and (3) The method is preferred.

It is preferable that each component is sufficiently dispersed in water. When each component is sufficiently dispersed in water, the main material liquid and the curing material liquid are mixed more uniformly, the gel time is stable, and the variation in the compressive strength of the solidified body is reduced.

[Curing material liquid]
The curing material liquid of the present invention is a curing material liquid used for curing a main material liquid containing lime and water. The curing material liquid is characterized by containing the above-mentioned curing material of the present invention and water.

Hereinafter, the water contained in the curing material liquid, the content of each component in the curing material liquid, and the method for producing the curing material liquid will be described. The details of the components contained in the curing material are the same as those in the curing material of the present invention described above.

(water)
Examples of water include clean water, industrial water, groundwater, river water, seawater and the like. Among these, clean water and industrial water are preferable in order to fully exert the effects of the present invention.

(Content of each component in the curing material liquid)
The lower limit of the content of amorphous aluminum hydroxide (including dry aluminum hydroxide gel) in the curing material liquid of the present invention is preferably 2 to 20 kg per 200 L of the cured material liquid (400 L of the total chemical solution). 4 to 12 kg is more preferable, and 6 to 8 kg is particularly preferable. When the content of amorphous aluminum hydroxide (including dry aluminum hydroxide gel) is equal to or higher than the above lower limit, the gel time is shortened, and the time required for developing strength after gelation is shortened. On the other hand, when it is not more than the above upper limit value, the viscosity of the cured material liquid is suppressed, so that the main material liquid and the cured material liquid are mixed more uniformly, and the variation in the compressive strength of the solidified body is further reduced. Further, when it is not more than the above upper limit value, pumping becomes easy, and the hardening material solution or the soil stabilizing chemical solution described later easily permeates the ground.

The content of the alkali metal carbonate in the curing material solution of the present invention is preferably 2 to 12 kg, more preferably 3 to 10 kg, and further preferably 4 to 8 kg per 200 L of the cured material solution (400 L of the total chemical solution). preferable. When the content of the alkali metal carbonate is within the above range, the gel time can be further shortened. In order to exert the effect of the present invention more, it is preferable that the insoluble component of the alkali metal carbonate does not remain when the curing material liquid is prepared from the curing material.

When the curing material liquid of the present invention contains an alkali metal hydroxide and / or an alkali metal silicate, the content of the alkali metal hydroxide and / or the alkali metal silicate in the curing material liquid of the present invention is the said. The pure content is preferably 0.5 to 5 kg, more preferably 1 to 4 kg, and even more preferably 1.5 to 3 kg per 200 L of the curing material solution (400 L of the total chemical solution). When the content of the alkali metal hydroxide and / or the alkali metal silicate is at least the above lower limit value, the gel time can be shortened particularly at a low temperature. Further, when the content of the alkali metal hydroxide and / or the alkali metal silicate is not more than the above upper limit value, the viscosity of the cured material is low, the degree of aggregation is low, and the pumping property can be improved.

(Manufacturing method of curing material liquid)
The curing material liquid of the present invention is produced by dispersing each component of the curing material in water using a known stirrer or the like. As the dispersion method, a method of dispersing the cured material produced in advance in water may be used, or a method of dispersing each component of the cured material in water in an arbitrary order may be used.

It is preferable that each component is sufficiently dispersed in water. When each component is sufficiently dispersed in water, the main material liquid and the curing material liquid are mixed more uniformly, and the variation in the compressive strength of the solidified body is further reduced.

[Chemical solution for soil stabilization]
The soil stabilizing chemical solution of the present invention contains the hardening material of the present invention, lime and water. That is, the chemical solution for soil stabilization of the present invention contains lime, dry aluminum hydroxide gel, alkali metal carbonate, and water. Alternatively, the soil stabilizing chemicals of the present invention include lime, amorphous aluminum hydroxide, alkali metal carbonates, alkali metal hydroxides and / or alkali metal silicates, and water. In addition to these components, the soil stabilizing chemical solution of the present invention may contain hydraulic cement, gypsum, and other additives.

The details of each component contained in the soil stabilizing chemical solution are the same as those in the above-mentioned curing material of the present invention, the main material solution according to the present invention, and the curing material solution of the present invention.

[Manufacturing method of chemicals for soil stabilization]
The method for producing the chemical solution for soil stabilization of the present invention may be a method of dispersing each component in water using a known stirrer or the like, or a method of adding a hardening material or a hardening material component to the main material solution. , A method of adding a component other than water in the main material solution to the cured material solution, or a method of mixing the main material solution and the cured material solution may be used. Above all, the method for producing the chemical solution for soil stabilization is preferably a method of mixing the main material solution and the hardening material solution, from the viewpoints of simplifying the work at the construction site and further enhancing the quick-setting property.

Hereinafter, a method of mixing the main material liquid and the curing material liquid will be described.
The two liquids may be mixed before being injected into the ground, or may be performed while injecting each liquid into the ground. If it is performed before injection into the ground, it may be mixed by a general stirring method using a stirrer or the like which is usually used when producing cement. When mixing each liquid while injecting it into the ground, for example, the main material liquid and the curing material liquid are individually mixed in a Y-shaped pipe, a stirrer, and an injection pipe using a pump having the same liquid feeding capacity per unit time. The method of pumping and mixing to the mixing chamber (in-pipe mixer / pipeline mixer) provided in the above, or the main material liquid and the curing material liquid are separately sent by the inner pipe and the outer pipe of the double pipe. , A method of merging and mixing the main material liquid and the hardened material liquid in the ground at the time of injection can be mentioned. In order to prevent both solutions from hardening during injection, the soil stabilizing chemical solution is preferably produced immediately before or during injection, and more preferably while being injected.

From the viewpoint of easy construction, it is preferable to mix the main material liquid and the cured material liquid in a volume ratio of 7: 3 to 3: 7, and it is more preferable to mix them in a volume ratio of 6: 4 to 4: 6. It is preferable to mix them in equal volumes, and it is particularly preferable to mix them in equal volumes.

[Ground stabilization method]
The ground stabilization method of the present invention includes a first aspect of injecting the above-mentioned chemical solution for soil stabilization of the present invention into the ground and a second aspect of mixing the main material solution and the hardening material solution in the ground. is there.
The specific method of the first aspect is a method of obtaining a soil stabilizing chemical solution in the same manner as the above-mentioned method for producing a soil stabilizing chemical solution of the present invention and injecting the chemical solution into the ground.
The specific method of the second aspect is a method in which the main material liquid and the curing material liquid are injected into the ground through separate injection pipes, and both liquids are merged and mixed in the ground. In this embodiment, at the time of injection, injection may be performed at ^{a pressure of 50 to 1000 kg / cm 2 using an injection tube having an injection nozzle.}

[Action effect]
According to the present invention, it is possible to provide a curing material having a short gel time, a curing material solution, a chemical solution for soil stabilization, a method for producing the chemical solution, and a ground stabilization method by using a dry aluminum hydroxide gel. Further, when using amorphous aluminum hydroxide, the gel time can be shortened even at a low temperature.
The effect of the present invention is presumed to be due to the following mechanism.

The dry aluminum hydroxide gel contained in the curing material used in the present invention is amorphized in a more reactive state as compared with the aluminum sludge used in Patent Document 1, and is different from the aluminum sludge. .. As a result, the reaction with alkali metal carbonate and lime proceeds very quickly, and it is thought that the gel time can be shortened.
Further, since the alkali metal hydroxide and alkali metal silicate used in the present invention have high alkalinity, the activity of amorphous aluminum hydroxide is increased and the reaction with alkali metal carbonate and lime proceeds rapidly. In addition, it is considered that a short gel time can be secured even at a low temperature by adding an alkali metal hydroxide and / or an alkali metal silicate.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.
The materials used in the following Examples and Comparative Examples, the methods for preparing the main material liquid and the cured material liquid, and various measurement / evaluation methods are as follows.

[material]
(Main material liquid)
-Hydraulic cement: Ordinary Portland cement-Gypsum: Type II anhydrous gypsum (brain value: 6500 cm ² / g)
・ Lime: Slaked lime (Brain value: 13000 cm ² / g)
・ Water reducing agent: sodium naphthalene sulfonate ・ formaldehyde condensate ・ setting retarder: citric acid ・ monohydrate ・ water: tap water

(Curing material liquid)
-Dry aluminum hydroxide gel (amorphous aluminum hydroxide): Tomita AD200P (manufactured by Tomita Pharmaceutical Co., Ltd., median diameter: 80 μm)
-Alkali metal carbonate: Soda ash (anhydrous sodium carbonate)
・ Sodium hydroxide: Granular ・ Alkali metal silicate: Sodium orthosilicate powder (pure 80%)
・ Water: Tap water

[Preparation method of main material liquid]
After using a material adjusted to 20 ° C and dispersing a mixture of lime, in some cases gypsum, water reducing agent, etc. in water in a room at 20 ° C, if hydraulic cement is used, usually Portland cement is dispersed and stirred. The main material liquid was obtained. The stirring was carried out using a magnetic stirrer, a stirrer bar having a length of 4 cm was placed in a 200 mL disc cup, and 200 mL of the main material liquid was contained, and the stirring was performed for a predetermined time under the conditions of a rotation speed of 650 to 750 rpm.
The content of each component in the main material liquid was as shown in Tables 1 to 3.

[Preparation method of curing material liquid]
Using a material adjusted to 20 ° C, a cured material mixed with dry aluminum hydroxide gel and alkali metal carbonate is dispersed in water in a room at 20 ° C, stirred, and if necessary, sodium hydroxide or the like is added to the cured material. Obtained liquid. The stirring was carried out using a magnetic stirrer, a stirrer bar having a length of 4 cm was placed in a 200 mL disc cup, and 200 mL of the curing material solution was contained, and the stirring was performed for a predetermined time under the conditions of a rotation speed of 650 to 750 rpm.
The content of each component in the curing material liquid was as shown in Tables 1 to 3.

[Measurement of gel time]
First, 50 mL of the obtained main material liquid and 50 mL of the curing material liquid are placed in 200 mL disc cups A and B, respectively, and the entire amount of the main material liquid is vigorously added to the disc cup B containing the curing material liquid, and then both liquids are vigorously added. The mixed solution of the above was immediately transferred to the disk cup A containing the main material solution, and further transferred to the disk cup B containing the curing material solution. It took about 2 seconds from the first mixing of the main material liquid and the curing material liquid to this point. Next, while observing the state of the disc cup B, the disc cup B was tilted 45 degrees to confirm the time until it stopped moving.

[Example 1]
In Example 1, the gel time at 20 ° C. was measured using the components shown in Table 1, the main material solution and the curing material solution prepared as described above with the contents of the components. The results are shown in Table 1.

Formulation 7 in Table 1 of Patent Document 1 describes that the gel time for the same formula is 9 seconds.
According to the present invention, as is clear from Table 1, it was confirmed that by using the same amount of dry aluminum hydroxide gel instead of aluminum sludge, the gel time comes in 3 seconds, which is much shorter than that of Patent Document 1. ..

[Example 2]
In Example 2, the gel time at 20 ° C. was measured using the components shown in Table 2, the main material solution and the curing material solution prepared as described above with the contents of the components. The results are shown in Table 2.

In Formulation 1 of Table 2 of Patent Document 1, it is described that the gel time is 14 seconds with the same formula as above.
According to the present invention, as is clear from Table 2, it was confirmed that by using the same amount of dry aluminum hydroxide gel instead of aluminum sludge, the gel time comes in 7 seconds, which is much shorter than that of Patent Document 1. ..

[Examples 3 to 5 and Comparative Examples 1 and 2]
In Examples 3 to 5 and Comparative Examples 1 and 2, gel times at 10 ° C. and 20 ° C. were used with the components shown in Table 3 and the main material solution and the curing material solution prepared as described above with the contents of the components. Were measured respectively. The results are shown in Table 3.

As shown in Example 3, it was confirmed that the gel time was within 10 seconds even at 10 ° C. by adding 2 kg of sodium hydroxide.
It was also confirmed that the gel time could be shortened by adding sodium orthosilicate as shown in Examples 4 and 5, and it was within 10 seconds by adding 2 kg.

The hardening material, hardening material solution, chemical solution for soil stabilization, manufacturing method of the chemical solution, and ground stabilization method of the present invention include, for example, voids in the ground, voids between the revetment embankment and the ground, cavities generated by liquefaction, and the like. It is useful for injecting into cavities on the back of tunnels to reinforce the ground.

Claims (6)

A curing material used by mixing with the main material liquid for curing a main material liquid containing lime and water, which comprises a dry aluminum hydroxide gel and an alkali metal carbonate. A curing material used by mixing with the main material liquid to cure the main material liquid containing lime and water, which is an amorphous aluminum hydroxide and an alkali metal carbonate, an alkali metal hydroxide and / or an alkali. A hardening material characterized by containing a metal silicate. A curing material liquid comprising the curing material according to claim 1 or claim 2 and water. A chemical solution for stabilizing soil, which comprises the curing material according to claim 1 or 2, and lime and water. A method for producing a chemical solution for soil stabilization, which comprises mixing a main material solution containing lime and water with the curing material solution according to claim 3. A ground stabilization method characterized by mixing a main material liquid containing lime and water with the hardened material liquid according to claim 3 in the ground.