JP2001081463A - Grout for ground - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a grout reduced in the shortening of a gelation time, especially, a gelation time in earth and made proof against leak, which grout is a non-alkaline silica sol comprising water glass, sulfuric acid, and an acidic aluminum salt and specified in an SiO2 concentration, a pH value, and a ratio of the net weight of sulfuric acid to the weight of the aluminum oxide of the aluminum salt. SOLUTION: This grout has an SiO2 concentration of 2-7%, a pH value of 2-6, and a ratio of the weight of the net of sulfuric acid to the weight of the aluminum oxide (in terms of aluminum oxide) of 10-100. In order to prevent ground from being liquefied, the ground is filled with a non-alkaline silica sol adjusted so that the molar ratio of the water glass used is as high as 3.5-5.0, the SiO2 concentration of the mixture is as relatively low as 2-7%, the amount of the acidic aluminum salt is adjusted so that the H2SO4/Al2O3 ratio may be 10-100, and the pH value is 2-6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called "leakage stopper" which reduces the gelation time, especially the gelation time in the soil, and is therefore suitable for construction work for preventing liquefaction of the ground. The present invention relates to a chemical solution for injecting ground suitable for water.

[0002]

2. Description of the Related Art In general, a liquid for injecting ground applied to a construction for preventing liquefaction of the ground is generally used for consolidating a wide range of ground.
It is necessary that continuous injection can be performed over a long period of time, and for this purpose, it is necessary to increase the gelation time of the drug solution. An acidic silica sol composed of water glass and an acid (mainly sulfuric acid) is conventionally known as this type of chemical solution. To increase the gelation time of this silica sol, the silica concentration must be low and the acidity must be high.

[0003] However, this kind of acidic silica sol can secure a stable and long gelling time under strong acidity.
The gelation time sharply decreases with the rise of H, and it becomes extremely difficult to adjust the gelation time. In addition, although a long gelling time can be maintained under strong acidity, the gelling time is greatly reduced in many cases depending on the properties of the soil in the soil. Therefore, when this kind of silica sol is applied to soil liquefaction prevention work, there is a problem in that continuous injection is performed for a long time to consolidate the ground over a wide area.

That is, when liquefaction is prevented by injecting silica grout into the ground, it is necessary to economically treat a wide area, so that silica grout having excellent durability and permeability is used, and the distance between injection holes is reduced. Usually, the injection must be continued for a long time as 2 to 4 m. (In normal injection, the injection hole interval is within 1 m.)

[0005] For example, when the interval between the injection holes is set to 2 m in the forward direction, if the injection pipes are arranged in a square with a buried interval of P = 2 m × 2 m and the injection speed f is set to 20 l / min, the improved flatness per injection hole is assumed. The area is Ap = 2m × 2m = 4m ² , and if the improved soil amount per stage (m ³ ) is V = 2m (improved height) × 4m ² = 8m ³ , the injection amount per stage (kl) Q = V × (0.35 to 0.40) = 2.8 m ^{3 to} 3.2 m ³ = 3.0 m ³ (average) (0.35 to 0.40: injection rate). Therefore, the injection must be performed for a long time, ie, the injection time per stage tr = 3 kl ÷ 0.02 kl / min = 150 min = 2.5 hours (injection continuation time).

When the distance between the injection holes is set to 4 m in the forward direction, the improvement area per injection hole is Ap = 4 m × 4 m = 16 m ² , and the amount of soil improved in one stage is V = 2 m (improved height). ) × 16 m ² = 32 m ³ , and the injection amount (kl) per stage is Q = V × (0.35 to 0.40) = 32 × (0.35 to 0.40) = 11.2 to 12.8 kl ≒ 12 kl (average), and if the injection speed f = 20 l / min, the injection must be performed for an injection time t = 12 kl ÷ 0.02 kl = 600 min = 10 hours per stage.

[0007] As described above, it is necessary that the liquid medicine for injection (injection material) used for preventing liquefaction can be continuously injected for a long time. However, if the injected material keeps in contact with the soil particles for a long time in the ground, the gelling time is shortened by the reaction with the soil during that time, so that continuous injection for a long time tends to be impossible.

[0008]

As a silica sol grout suitable for construction for preventing liquefaction of the ground, usually, a gelation time can be kept long, and particularly, a gelation time in soil can be reduced as short as possible. It is also necessary to be able to reduce the amount of salt generated at the same time, and at the same time it is necessary to obtain a ground injection chemical solution that is suitable for preventing leakage of the injected chemical solution, that is, for preventing leakage.

Therefore, an object of the present invention is to reduce the gelation time, especially the gelation time in the soil, and to reduce the time. Therefore, the object of the present invention is to prevent the liquefaction of the ground, and at the same time, to prevent the leakage of the injected chemical solution. It is an object of the present invention to provide a medicament for injecting ground into which the above-mentioned disadvantages of the known art are improved.

[0010]

According to the present invention, there is provided, according to the present invention, a non-alkali silica sol comprising water glass, sulfuric acid and an acidic aluminum salt, wherein the SiO ₂ concentration is 2 to 6%. % And the pH value are 2 to 6, and the weight of pure sulfuric acid / the weight of aluminum of the aluminum salt is 10 to 100.

Further, in order to achieve the above-mentioned object, according to the present invention, it comprises water glass, sulfuric acid, an acidic aluminum salt and an aluminum agent, and has a SiO ₂ concentration of 2 to 2.
7% and a pH value of 3-9, and pure sulfuric acid weight /
The aluminum weight of the aluminum salt is 10 to 100.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

In order to lengthen the gelation time of the non-alkali silica sol, it has been conventionally considered to lower the silica concentration and increase the acidity.

On the other hand, the present inventors have developed a method of extending the gelling time by using an aluminum salt exhibiting acidity, and have completed the present invention. This is presumably because part of the silica particles is replaced by aluminum, and aluminum adsorbs OH ions into the liquid to enhance the stability of the silica sol.

In order to reduce the amount of salts other than silica to be produced, it is more effective to use a high molar ratio of water glass.

When sulfuric acid, which is a strong acid, is used as an acid, the amount of salts other than silica as a reaction product can be reduced. That is, water glass having a low silica concentration and a high molar ratio in a non-alkali region and sulfuric acid can be used. By using this, a long gelation time can be obtained at the same pH. The reason is considered to be that the silica sol in this region promotes gelation by salting out the silica colloid due to the presence of formed salts other than the silica component, so that the gelling time can be maintained longer by reducing the formed salts.

Further, the present invention has found that when the silica sol in this region penetrates into the ground, the gelation accompanying the contact with the soil particles can be little promoted, and continuous injection for a long time is possible. Is completed.

Regarding the non-alkali silica sol, an example of how the change in the molar ratio of water glass and the addition of an aluminum salt exhibiting acidity affects the relationship between pH and the gelation time in the case of a SiO ₂ concentration of 4% Investigation and graphical representation of the results showed the tendency shown in FIG. That is, the gelation time corresponding to the same pH value is delayed as the molar ratio of water glass increases, and further delayed by the addition of an acidic aluminum salt.

From the above, with regard to the non-alkali silica sol in the non-alkali region, in order to delay the gelation time, the concentration of the water glass is reduced, the molar ratio of the water glass is increased, and an aluminum salt exhibiting acidity is further contained. It is desirable to make it work.

Further, the gelling time in the soil is significantly shortened by the conventional acidic silica sol, but the gelling time in the non-alkaline silica sol as described above is reduced by reducing the gelation time in the soil. Is retained and has excellent permeability.

Therefore, according to the present invention, in a mixed system of water glass, sulfuric acid and an aluminum salt exhibiting acidity, the concentration of water glass is made as low as 7% or less, preferably 6% or less as SiO ₂ , but when 2% or less, gel is reduced. Although the formation time is prolonged, the strength is extremely weak and is not suitable.

In terms of strength, the uniaxial compression strength of consolidated sand is usually 0.1.
It is thought that if the concentration is about 5 to 1.0 kgf / cm ^2, the gel in the gaps between the sand particles does not break down and no negative dilatancy occurs due to the repeated shearing force during the earthquake, so that liquefaction does not occur.

With respect to the molar ratio of water glass, JIS No. 3 water glass having a molar ratio of 3.1 to 3.3 is generally and widely used. .0
Use a high molar ratio of water glass. Due to the high molar ratio, a small amount of sulfuric acid which has a small alkali content and reacts with the alkali is sufficient. This means that the amount of salt generated by the reaction is reduced by itself, and the reduction of the gelation time in the soil is reduced. Water glass with a lower alkali molar ratio of 5.0 or more is difficult to produce, is not suitable for industrial production, and is practically difficult to use.

The amount of the aluminum salt exhibiting acidity is related to the amount of sulfuric acid, and the value of sulfuric acid (pure H ₂ SO ₄ : weight) / Al (weight) of the aluminum salt (hereinafter referred to as H ₂ SO ₄ / Al value) is obtained. It is desirable to add so as to be in the range of 10 to 100. When the H ₂ SO ₄ / Al value is 10 or less, that is, when the amount of sulfuric acid is small and the amount of aluminum salt is too large, it is useful for delaying the gelation time. The generation is increased and the resulting gel becomes soft. On the other hand, if it exceeds 100, the effect of the addition of the aluminum salt becomes insignificant.

Examples of the aluminum salt exhibiting acidity include aluminum sulfate, aluminum chloride, polyaluminum chloride and the like, and the addition of these also has the effect of reducing the amount of sulfuric acid used.

When a non-alkaline silica sol having a pH of 2 to 6 is injected as an acid, the pH generally rises and approaches neutrality. Depending on the properties of the soil to be injected, the injection at pH 2 or lower may not raise the pH to the neutral region, and the injection at pH 6 or higher may generally result in rapid gelation and insufficient permeation.

From the above, the non-alkali silica sol consisting of water glass, sulfuric acid and an aluminum salt exhibiting acidity is injected into the ground to prevent liquefaction of the ground, and the molar ratio of the water glass used is set to 3.5 to 3.5. 5.0, the concentration of SiO ₂ in the mixture is relatively low, preferably 2 to 7%, and more preferably 3 to 6%.
A specific alkaline silica sol mixed so that the ₂ SO ₄ / Al value falls within the range of 10 to 100 and the pH falls within the range of 2 to 6 is injected into the ground.

As a result, the gelation time is long, and the gelation time in soil is not shortened very much, and it shows extremely excellent permeability.
It is possible to obtain a very favorable liquid for ground injection for preventing liquefaction. Since such a chemical solution has a long gelation time, it is necessary to prevent the above-mentioned chemical solution from leaking at the same time. For that purpose, a chemical solution in which the gelation time is mixed within several minutes from the instantaneous setting is required.

For this purpose, it is convenient to apply the above conditions as much as possible. Therefore, the molar ratio of water glass, the concentration, and the amount of aluminum salt are not changed and are kept as they are, and an alkaline agent is added to raise the pH to 3 to 9, thereby shortening the gelation time. pH
Is increased to 9 or more, the gel passes through the instantaneous setting region, so that the gel tends to be non-uniform and the amount of alkali used increases.
Further, when the pH is set to 3 or less at such a SiO ₂ concentration, it is difficult to obtain a short gelation time of several minutes or less.

Examples of the alkali agent include a soluble alkali agent such as sodium hydrogen carbonate, a sparingly soluble alkali agent such as calcium hydroxide, magnesium hydroxide, calcium carbonate and magnesium carbonate, and water glass. The pH can be increased by adding an alkali agent to adjust the gelation time.However, in the case of a poorly soluble alkali agent, it is relatively easy to adjust, especially in a weakly acidic to neutral region, from the viewpoint of solubility. It is.

In the present invention, in order to adjust the gelation time, another acid such as phosphoric acid, an acidic phosphate, an aluminum salt, or the like may be used in combination, or a calcium salt as a gelation accelerator, any water-soluble agent may be used. It is a matter of course that an alkali agent, a poorly soluble alkali agent, an optional sequestering agent, cement, slag, or the like may be used in combination.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to examples, but the present invention is not limited to these examples.

1. Materials used (1) Water glass No. 5 water glass and JIS No. 3 water glass are used. (A) No. 5 water glass specific gravity (20 ° C.) 1.32, SiO ₂ 25.5%, Na ₂
O 7.03% Molar ratio 3.75 (b) JIS No. 3 water glass Specific gravity (20 ° C) 1.39, SiO ₂ 29.2%, Na ₂
O 9.5% molar ratio 3.17

(2) Sulfuric acid 75% Industrial sulfuric acid

(3) Aluminum salt exhibiting acidity Aluminum sulfate and aluminum chloride are used. (A) Aluminum sulfate An aluminum sulfate solution having a specific gravity of 1.32 and an Al content of 8%. (B) aluminum chloride in an aluminum purity of 97% hexahydrate chloride _{(AlCl 3 · 6H 2 O)} . Therefore, 26.98 / 24 as Al
It contains 1.45 x 0.97 x 100 = 10.8%.

(4) Alkali Agent Sodium hydrogen carbonate was taken as an example of a soluble alkali agent, and magnesium hydroxide was taken as an example of a sparingly soluble alkali agent. (A) Sodium bicarbonate reagent primary grade NaHCO ₃ (b) Magnesium hydroxide reagent primary grade Mg (OH) ₂

(5) Sand Toyoura standard sand as fine sand and sea sand from Chiba prefecture as silty sand.

2. Measurement method (1) pH Measured with a glass electrode pH meter.

(2) Gelation time (a) Gelation time of homogel Measured by the inverted cup at 20 ° C. (B) Gelling time in soil The grout solution was mixed with sand at 20 ° C., stopped, the supernatant was discarded, a bamboo skewer was pierced with sand and pulled out, and the time when a trace remained was measured as the gelling time in soil.

(3) Sandgel Uniaxial Compressive Strength A Santogel made with Toyoura standard sand was sealed and cured with polyvinylidene chloride (20 ° C.) for 10 days.

3. Example (1) A system composed of water glass-sulfuric acid-acidic aluminum salt An aqueous solution of water glass was used as solution A, and an aqueous solution of aluminum salt exhibiting sulfuric acid / acidity was used as solution B, and SiO of AB combined liquid was used.
₂ (%), pH, H ₂ SO ₄ / Al value, gel time (homogel, in soil), sandgel uniaxial compressive strength were measured.

The results are shown in Table 1 by comparing Examples within the scope of the present invention with Comparative Examples outside the scope.

[0043]

[Table 1]

In Table 1, Examples Nos. 1 to 6 and Comparative Examples Nos. 1 to 6 all had the same SiO ₂ concentration. Comparative example
Nos. 1 and 2 are each composed of a system of No. 3 water glass, No. 5 water glass and sulfuric acid, and Examples Nos. 1 to 6 are examples in which an aluminum salt is added thereto. In these systems, depending on the pH value, the reduction of the soil gelation time is relatively small. It is also slightly superior in strength.

It is considered that Comparative Example No. 3 has a pH of 2 or less and does not reach the neutral region even in soil.

Comparative Example No. 4 has a pH of 6 or more and has a short gelation time, which seems to be unsuitable for preventing liquefaction.

In Comparative Example No. 5, the amount of sulfuric acid was small relative to the amount of aluminum salt (H ₂ SO ₄ / Al <10), and a paste-like precipitate of aluminum hydroxide was generated, and the strength was extremely weak. Conversely, Comparative Example No. 6 (H ₂ SO ₄ / A
In the case of l <100), the effect of adding the aluminum salt is hardly exhibited, and the gelation time in soil is greatly reduced. (Compared with Example NO.2).

Comparative Examples Nos. 7 and 8 correspond to the examples, and the effect of the addition of the aluminum salt is clearly shown even when the SiO ₂ concentration is different from that described above.

Comparative Example No. 9 has a low SiO ₂ concentration (2.0%).
Below), the strength is extremely deteriorated.

In Comparative Example No. 10, the SiO ₂ concentration was too high (7% or more), and it was difficult to maintain a long gelation time even in soil even when the pH was lowered.

From the above, it can be fully expected that the chemical solution for ground injection under the conditions of the present invention is suitable for preventing liquefaction.

(2) Permeation test From the above Examples and Comparative Examples, the present invention is expected to have excellent permeability, but just in case, an acrylic pipe having an inner diameter of 50 mm and a length of 5 m shown in the injection test apparatus of FIG. The sand 2 as a model ground is compacted in 1 so as to have a relative density of 60%. An injection material was injected at an injection pressure of 0.8 kgf / cm ² from the injection port 3, and the relationship between each distance penetrated from the injection port 3, the extension of the penetration extension, and the strength was observed. In FIG. 2, 4 is an overflow tank, and 5 is an outlet. Table 2 shows the results.

[0053]

[Table 2]

According to Table 2, the system uniformly penetrating the entire length is as follows:
The consolidation strength was almost uniform over the entire area. As a matter of course, in a system that can only partially penetrate, the consolidation strength decreases from the bottom to the top. The penetration of sea sand from Chiba prefecture is inferior to that of Toyoura standard sand because the gelation time is generally shorter.

Here, in the penetration tests Nos. 1, 2, 3, 4, 5, 6 and 7 and 8, the contents of the examples and comparative examples are almost similar.

Therefore, the penetration test No. 1 according to the example,
Comparing 3, 5, and 7 with the permeation tests Nos. 2, 4, 6, and 8 of the corresponding comparative examples, respectively,
That is, in the present invention, the permeation distance and the consolidation strength, particularly the permeation, are clearly superior.

(3) System consisting of addition of an alkali agent The above-mentioned chemical solution is injected to prevent liquefaction, and an alkaline agent is added to the above-mentioned chemical solution to increase the pH as a leak stopper for preventing the leakage of the chemical solution. The gelation time is shortened, and if possible, it is adjusted so as to solidify in a few minutes to an instantaneous setting.

As an example, Example No. 1 and Comparative Example No. 1 in Table 1 were used.
Are shown in Table 3.

[0059]

[Table 3]

In Table 3, it is easy to shorten the gelation by using an alkali agent, and to shorten the gelation from several seconds to several minutes. In general, the compaction strength seems to be relatively higher in the examples than in the comparative examples. In addition, insoluble magnesium hydroxide as an alkali agent has a longer gelation time than soluble sodium hydrogen carbonate, and seems to have a slightly higher consolidation strength.

From the above examples and the permeation test, it can be seen that the non-alkali silica sol according to the present invention is clearly superior to the conventional acidic silica sol as a chemical for preventing liquefaction. Also, it can be seen that it is suitable as a leak stop.

[0062]

As described below, the ground injection chemical solution according to the present invention has the following effects.

1. The gelation time is long, and the reduction of the gelation time especially in the soil is small. 2. 2. Excellent permeability A small amount of sulfuric acid is sufficient. 4. Therefore, it is a chemical for ground injection suitable for construction for preventing liquefaction of the ground. 5. It is suitable as a leak stopper for preventing leakage of a chemical solution.

[Brief description of the drawings]

FIG. 1 is a graph showing the effect of the molar ratio of water glass on the relationship between pH and gelation time.

FIG. 2 is a cross-sectional view of an experimental device for injecting a drug solution of the present invention.

[Explanation of symbols] [Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pipe 2 Sand 3 Inlet 4 Overflow tank 5 Outlet

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[Procedure amendment]

[Submission date] October 15, 1999 (1999.10.
15)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 1

[Correction method] Change

[Correction contents]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Claim 2

[Correction method] Change

[Correction contents]

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction contents]

[0010]

According to the present invention, there is provided, according to the present invention, a non-alkali silica sol comprising water glass, sulfuric acid and an acidic aluminum salt, wherein the SiO ₂ concentration is 2 to 7 %. % And pH value are 2 to 6, and the weight of pure sulfuric acid / the weight of aluminum salt in terms of aluminum oxide is 10 to 100.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction contents]

Furthermore, in order to achieve the above object, according to the present invention consists of a aluminum salt and alkali agent exhibiting water glass and the sulfuric acid, SiO ₂ concentration of from 2 to 7%
And the pH value is 3 to 9, and the weight of pure sulfuric acid / the weight of aluminum salt in terms of aluminum oxide is 10 to 100.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0024

[Correction method] Change

[Correction contents]

The amount of the aluminum salt exhibiting acidity is related to the amount of sulfuric acid, and the value of sulfuric acid (pure H ₂ SO ₄ : weight) / amount (weight) of aluminum salt in terms of aluminum oxide (hereinafter referred to as H ₂ S)
O ₄ / Al ₂ O ₃ value) is desirably in the range of 10 to 100. H ₂ SO ₄ / Al ₂ O ₃
When the value is 10 or less, that is, when the amount of sulfuric acid is small and the amount of aluminum salt is too large, it is useful for delaying the gel time, but the occurrence of paste-like precipitation of aluminum hydroxide composed of water glass-aluminum salt increases, The gel becomes soft. On the other hand, if it exceeds 100, the effect of the addition of the aluminum salt becomes insignificant.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0027

[Correction method] Change

[Correction contents]

From the above, the non-alkali silica sol consisting of water glass, sulfuric acid and an aluminum salt exhibiting acidity is injected into the ground to prevent liquefaction of the ground, and the molar ratio of the water glass used is set to 3.5 to 3.5. 5.0, the concentration of SiO ₂ in the mixture is relatively low, preferably 2 to 7%, and more preferably 3 to 6%.
A specific alkaline silica sol mixed so that the ₂ SO ₄ / Al ₂ O ₃ value falls within the range of 10 to 100 and the pH falls within the range of 2 to 6 is injected into the ground.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0035

[Correction method] Change

[Correction contents]

(3) Aluminum salt exhibiting acidity Aluminum sulfate and aluminum chloride are used. (A) Aluminum sulfate An aluminum sulfate solution having a specific gravity of 1.32 and an Al ₂ O ₃ equivalent of 8%. (B) aluminum chloride in an aluminum purity of 97% hexahydrate chloride _{(AlCl 3 · 6H 2 O)} . Therefore, the equivalent amount of Al ₂ O ₃
(101.96 / 241.45 x 2) x 0.97 x 100 = 2
This corresponds to 0.5% of Al ₂ O ₃ .

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0041

[Correction method] Change

[Correction contents]

3. Example (1) A system composed of water glass-sulfuric acid-acidic aluminum salt An aqueous solution of water glass was used as solution A, and an aqueous solution of aluminum salt exhibiting sulfuric acid / acidity was used as solution B, and SiO of AB combined liquid was used.
₂ (%), pH, H ₂ SO ₄ / Al ₂ O ₃ value, gelation time (homogel, in soil), and sandgel uniaxial compressive strength were measured.

[Procedure amendment 9]

[Document name to be amended] Statement

[Correction target item name] 0043

[Correction method] Change

[Correction contents]

[0043]

[Table 1]

[Procedure amendment 10]

[Document name to be amended] Statement

[Correction target item name] 0047

[Correction method] Change

[Correction contents]

In Comparative Example No. 5, the amount of sulfuric acid was small relative to the amount of aluminum salt (H ₂ SO ₄ / Al ₂ O ₃ <10), and a paste-like precipitate of aluminum hydroxide was generated, and the strength was extremely weak. is there. Conversely, Comparative Example No. 6 (H ₂ SO
_{In the case of 4} / Al ₂ O ₃ > 100), the effect of adding the aluminum salt is hardly exhibited, and the gelation time in soil is greatly reduced. (Compared with Example NO.2).

[Procedure amendment 11]

[Document name to be amended] Statement

[Correction target item name] 0048

[Correction method] Change

[Correction contents]

Comparative Examples Nos. 7 and 8 correspond to Examples Nos . 7 and 8, and even when the SiO ₂ concentration is different from the above, the effect of adding the aluminum salt is clearly shown.

Claims (3)

[Claims] 1. A non-alkaline silica sol comprising water glass, sulfuric acid and an acidic aluminum salt,
iO ₂ concentration of 2-6% and pH value of 2-6, and pure sulfuric acid weight / aluminum salt aluminum weight = 1
A chemical liquid for ground injection characterized by being 0 to 100. 2. An aqueous solution comprising water glass, sulfuric acid, an aluminum salt exhibiting acidity, and an alkali agent, wherein the SiO ₂ concentration is 2-7.
% And a pH value of 3 to 9, and a weight of pure sulfuric acid / aluminum weight of aluminum salt = 10 to 100. 3. The chemical liquid for injection into the ground according to claim 1, wherein the molar ratio of the water glass is 3.5 to 5.0.