JP2000070700A - Method for producing suspension and method for injecting the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily and efficiently inject suspension type grout into the cracks or gaps of the ground, base rock or concrete, in a case producing a suspension by dispersing the powder in water, by dispersing the powder by ultrasonic waves when or after the powder and water are mixed and removing flocculated lumps of the powder from the suspension. SOLUTION: Water, powder and, further, if necessary, a dispersant are charged in a stirring tank 1 to be stirred and mixed and this mixed soln. is transferred to an ultrasonic dispersing device 3 to be accelerated in dispersion. The suspension obtained herein is transferred to a classifier such as a cyclone 4 to separate flocculated lumps and these lumps are discharged from the bottom part of the cyclone and the suspension is taken out of the upper part of the cyclone. When the suspension wherein the powder is dispersed in water is injected into the cracks or gaps of the ground, base rock or concrete by using a pipe, ultrasonic waves are applied to the suspension. As the place applying ultrasonic waves at this time, the outlet part of the injection pipe is effective. As the powder, an inorg. hydraulic material such as cement is used and it is pref. to add the dispersant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to preventing spring water, improving soft ground, and stopping and strengthening rock and concrete.
Ground, bedrock, or a method for producing a suspension suitable for producing suspended grout or the like used by filling cracks or voids in concrete, and such a suspension for ground, bedrock, or concrete The present invention relates to an injection method for filling cracks and voids.

[0002]

2. Description of the Related Art Conventionally, in order to prevent spring water, improve soft ground, and strengthen rock and concrete, a suspension grout in which cement-based powder is dispersed in water in cracks or voids in the ground, rock or concrete has been used. The grouting method of filling grout is applied. The grout used in this grout injection method is generally a suspension obtained by mixing and mixing Portland cement, clay minerals, blast furnace slag, fly ash, and other mixed powders with a rotating blade to disperse in water. is there. Such suspended grout is applied to the ground,
Injected and filled into cracks or voids in rock or concrete.

[0003]

In order to inject such suspension grout into cracks in concrete or voids in the ground, the dispersed particles in the suspension grout must be dispersed easily. The particles must be of a size that can easily pass through the voids or crack voids between the soil particles.

However, in the conventional cement-based suspension, each powder particle dispersed in water is re-agglomerated into a large particle mass. Agglomerates are trapped and clogged, which hinders subsequent injection of the suspension. For this reason, in many cases, suspended ground grout cannot be injected into the fine-grained sandstone layer, and ground improvement and ground reinforcement cannot be performed, and in many cases, construction work cannot be started.

On the other hand, if the agglomerates of the powder particles can be removed from the suspended grout, the permeability of the grout into the narrow gap can be improved, and efficient injection can be performed.

Accordingly, the present invention provides an easy and efficient method for removing suspended grout into cracks and voids in the ground, bedrock or concrete by removing agglomerates of powder particles in the suspension and increasing its permeability. It is an object of the present invention to provide a method for producing a suspension capable of being injected into a suspension and a method for injecting the suspension.

[0007]

The method for producing a suspension according to the present invention is a method for producing a suspension by dispersing a powder in water, wherein the powder is mixed with water and / or after mixing. After the powder is dispersed by ultrasonic waves, agglomerated particles of the powder are removed from the suspension.

According to this method, by promoting the dispersion by applying ultrasonic waves, the agglomeration of the powder particles is prevented, the agglomerates are loosened, and the remaining agglomerates are removed. Almost no suspension can be produced with excellent injection and permeability.

In the present invention, bubbles in the suspension can be reduced by ultrasonic waves, and the filling of the suspension after injection can be enhanced.

In the method for producing a suspension of the present invention, a method using a cyclone, a centrifugal separator, or sedimentation can be used for removing aggregates.

The method of injecting a suspension according to the present invention is a method of injecting a suspension in which powder is dispersed in water into an object to be injected using a pipe. It is characterized by doing.

[0012] In this method, too, the agglomerates in the suspension are disentangled and the bubbles are removed by the ultrasonic wave, so that the suspension has excellent injection, permeability and filling properties, and is easy and efficient. The suspension can be injected and filled into the injection target.

In the method for injecting a suspension according to the present invention, it is preferable that the ultrasonic wave is applied to an outlet of a pipe for injecting the suspension into an object to be injected.

In the method for producing a suspension and the method for injecting the same according to the present invention, the powder dispersed in the suspension may be an inorganic hydraulic material powder. By adding 0.5 to 5.0% by weight of a dispersant to the suspension, the dispersibility of the powder is further increased to prevent the formation of agglomerates, and the formed agglomerates are easily loosened. Will be able to

[0015]

Embodiments of the present invention will be described below in detail.

In the method for producing a suspension according to the present invention, first, powder is mixed with water with a stirring rod or the like using a usual rotating blade to prepare a suspension. Later, ultrasonic waves are applied to prevent agglomeration of the powder and to loosen agglomerates in the liquid. In preparing this suspension, the ultrasonic waves applied to the mixing system had an output of 5-2000 W and a frequency of 10-8.
It can be applied using a normal ultrasonic transmitter of 0 kHz, and the application time of the ultrasonic wave is set in such a condition that the aggregates are sufficiently loosened according to conditions such as the volume of the mixed system and the concentration of the suspension. It is determined as appropriate.

In the present invention, after the powder is sufficiently dispersed in this way, the aggregate of the powder is removed from the obtained suspension. The method for removing the aggregates includes a method of allowing the suspension to stand as it is to precipitate and separate the aggregates, a method of classifying with a cyclone, and a method of classifying with a centrifuge.

FIG. 1 is a schematic sectional view showing an embodiment of the method for producing a suspension according to the present invention.
Water and powder and, if necessary, a dispersant described below are added to the stirring tank 1 and mixed by stirring. The mixed liquid is transferred to the ultrasonic dispersion device 3 and ultrasonic waves are applied to further promote the dispersion ( The dispersant may be introduced into the ultrasonic dispersion device 3.) Then, the obtained suspension is transferred to a classifier such as a cyclone 4 to separate agglomerates. Agglomerates are discharged from the bottom of the cyclone 4, and the suspension is removed from the top of the cyclone 4.

In the method of injecting a suspension according to the present invention, a method of injecting a suspension in which powder is dispersed in water into an object to be injected into a ground, a bedrock, concrete cracks or voids using a pipe, The suspension is injected with ultrasound. In this case, it is effective that the ultrasonic wave is applied to the outlet of the injection pipe. For example, as shown in FIG. 2A, if the pipe 5 has an opening 5A at the tip of the pipe 5 and sends out the suspension in the same direction as the flow of the suspension in the pipe 5, the opening of the pipe 5 It is preferable that the ultrasonic transmitter 6 is attached to the inner wall portion in the vicinity of the portion 5A, and ultrasonic waves are applied to the suspension to feed the suspension while loosening the aggregates. FIG.
As shown in FIG.
A, 7B, which sends out the suspension in a direction intersecting with the flow of the suspension in the pipe 7, the ultrasonic transmitter 6 is disposed inside the vicinity of the openings 7A, 7B at the tip of the pipe 7. It is preferable to feed the suspension while applying ultrasonic waves to the suspension so as to loosen agglomerates. Also in this injection method, the ultrasonic wave has an output of 5-2000 W and a frequency of 10-8.
It can be applied using a normal ultrasonic transmitter of 0 kHz.

The pipe used for injecting the suspension usually has a diameter of 80 to 120 mm.

In the method for producing a suspension and the method for injecting a suspension according to the present invention, examples of the powder dispersed in the suspension include inorganic hydraulic materials such as cement, blast furnace slag, and slaked lime. In addition, it can be applied to benite, clay, and the like.

The present invention is particularly applicable to the preparation of a suspension, in which a Blaine value of 8000 to 20000 cm ² /
It is effectively applied to a suspension in which about g of hydraulic fine inorganic powder is suspended at a water solids ratio of 1 to 10.

In addition, it is preferable to add a dispersant to the suspension according to the present invention in order to prevent agglomeration of the powder and facilitate loosening of the agglomerates. In this case, various surfactants are suitable as the dispersant. Specifically, lignin sulfonate and its derivatives, oxycarboxylates, polyol derivatives, polycarboxylates, and formalin naphthalene sulfonate are highly condensed. Use of chemical admixtures whose main components are products, melamine sulfonate formalin polycondensates, alkyl allyl sulfonic acid polymers, highly condensed triazine compounds, methylol melamine condensates, nitrogen-containing sulfonates, amino sulfonates, etc. Can be.

The amount of the dispersing agent to be added is appropriately adjusted depending on the degree of loosening of the agglomerates and the injection properties.
It is preferably 5.0% by weight, particularly preferably 1 to 3% by weight.

If the amount of the dispersing agent is too small, no good effect is obtained, while if it is too large, the cost is high. When adding a dispersant, there is no particular limitation on the time of addition,
Either at the time of mixing the powder with water or at the time of applying the ultrasonic wave after the mixing in the method of claim 1, it may be previously mixed with the powder and / or water.

The particle diameter of the dispersed particles in the suspension is preferably not more than 50 μm in terms of permeability at the time of injection, and in particular, in the method of claim 1, classification is performed. It is preferable to remove aggregates having a particle diameter of 10 μm or more.

In the method for injecting a suspension of the present invention, the suspension produced by the method for producing a suspension of the present invention may be injected, but ultrasonic waves are applied at the time of the injection. By doing so, it is possible to inject the suspension with good injection efficiency, especially, not limited to the suspension produced by applying ultrasonic waves and removing agglomerates according to the suspension production method of the present invention, A sufficient effect can be obtained with a suspension obtained by simply stirring and mixing the powder and water, and if necessary, the dispersant according to a conventional method.

[0028]

The present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to the following examples unless it exceeds the gist.

Example 1 Cement 10 having a Blaine specific surface area of 13000 g / cm ²
0 parts by weight and 3 parts by weight of a surfactant (a high-condensate of β-naphthalene sulfonic acid formalin) are added to 600 parts by weight of water and mixed with a hand mixer at 500 rpm for 60 seconds.
Immediately after this mixing, an ultrasonic homogenizer / SONIFI
Ultrasonic waves are applied to the suspension at ER 250 (frequency: 20 kHz, output: 20 W) for 60 seconds, and then the suspension is allowed to stand for 30 minutes to precipitate aggregates, and the separated liquid is used for a cement strength test. Standard sand (particle size 0.1-0.3mm)
Or sand on the ground at the site where the dam is to be constructed (particle diameter 8 μm to 2.0
mm) by the following method, and the results are shown in Table 1.

After the application of the ultrasonic waves,
The solid content concentration of the liquid from which the aggregate was separated by standing for 0 minutes was 50% before standing, and the particle diameter of the suspension was 10 μm.
The ratio of particles of m or more was 5.4% before standing,
After standing, it was reduced to 0.2%.

[Penetration test] 100 cc of the suspension was placed in a beaker and allowed to flow over the test sand filled in a 200 ml cylindrical separating funnel, and the average penetration depth was mm.
It was measured in units. The test was performed three times, and the results were shown as average values.

COMPARATIVE EXAMPLE 1 In Example 1, a suspension obtained by mixing with a hand mixer without applying and stopping ultrasonic waves was subjected to a similar permeability test, and the results are shown in Table 1. .

Comparative Example 2 A suspension obtained by mixing with a hand mixer and applying ultrasonic waves without standing still in Example 1 was similarly subjected to a permeability test, and the results are shown in Table 1. Was.

[0034]

[Table 1]

From Table 1, it can be seen that the suspension from which aggregates have been removed by settling after application of ultrasonic waves is extremely excellent in permeability.

Example 2 According to the method shown in FIG.
g / cm ² of blast furnace slag powder (100 parts by weight) and a surfactant (β-naphthalene sulfonic acid highly condensed product) (5 parts by weight) were added to water (400 parts by weight), and the mixture was stirred at 200 rpm in a stirring tank at 200 rpm.
After mixing for 0 seconds, the frequency is 20 kHz with an ultrasonic dispersion device.
z, output: 20 W ultrasonic wave is applied for 30 seconds, and then
A suspension obtained by classification using a cyclone (diameter: 100 mm) was subjected to a permeability test in the same manner as in Example 1, and the results are shown in Table 2.

After the application of the ultrasonic wave, the solid content of the suspension classified by the cyclone is 70% before the classification.
%, And the ratio of particles having a particle diameter of 10 μm or more in the suspension was 3.2% before classification, but was 0.3% after classification.
It was reduced to 8%.

Comparative Example 3 A suspension obtained by mixing in a stirring tank without applying ultrasonic waves and classifying by cyclone in Example 1 was similarly subjected to a permeability test, and the results are shown in Table 2. Indicated.

Comparative Example 4 A suspension obtained by mixing in a stirring tank and applying ultrasonic waves in Example 1 without performing classification by cyclone in Example 1 was similarly subjected to a permeability test. It was shown to.

[0040]

[Table 2]

From Table 2, it can be seen that the suspension obtained by applying ultrasonic waves and then classifying with a cyclone to remove aggregates has extremely excellent permeability.

Example 3 Cement 10 having a Blaine specific surface area of 13000 g / cm ²
0 parts by weight and 3 parts by weight of a surfactant (bisphenolsulfonic acid-based condensate) are added to 600 parts by weight of water to obtain 500 parts by weight.
A suspension was prepared by mixing for 60 seconds with a hand mixer at rpm. For this suspension, a permeability test for cement standard strength sand (particle diameter: 0.1 to 0.3 mm) or ground sand (particle diameter: 8 μm to 2.0 mm) at the site where the dam is to be constructed is performed by the following method. The results are shown in Table 3.

[Penetration test] A suspension (100 cc) was placed in a beaker and allowed to flow while applying ultrasonic waves from above the test sand filled in a 200-ml cylindrical separating funnel, and the average penetration depth was measured. Was measured in mm. The ultrasonic wave was applied to the suspension accumulated at the top when the suspension was injected into the separating funnel by an ultrasonic homogenizer / SONIFIER 250 (frequency: 20 kHz, output: 20 W). The test was performed three times, and the results were shown as average values.

Comparative Example 5 In Example 3, a penetration test was carried out in the same manner except that no ultrasonic wave was applied. The results are shown in Table 3.

[0045]

[Table 3]

From Table 3, it can be seen that efficient injection can be achieved by injecting the suspension while applying ultrasonic waves.

[0047]

As described in detail above, according to the method for producing a suspension and the method for injecting the same according to the present invention, by removing agglomerates of powder particles in the suspension and increasing the permeability thereof,
Suspension grout and the like can be easily and efficiently injected and filled into cracks and voids in the ground, bedrock or concrete.

According to the present invention, a suspension grout using a cement made of fine particles, which could not be injected conventionally because of the presence of coarse particles of agglomerates, can be used in a large amount on fine-grained sandstone rock and ground. And it can penetrate smoothly. In addition, by reducing the bubbles in the suspension grout by applying ultrasonic waves, the filling property of the grout after permeation is improved, and the water stop or strengthening of the ground or the bedrock can be effectively performed.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an embodiment of a method for producing a suspension according to the present invention.

FIG. 2 is a schematic sectional view showing an embodiment of the suspension injection method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stirring tank 2 Stirrer blade 3 Ultrasonic dispersion device 4 Cyclone 5, 7 Pipe 6 Ultrasonic transmitter

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) E21B 33/13 E21B 33/13 // C09K 103: 00 (72) Inventor Toshiyuki Nakamura Kitabukuro-cho, Omiya City, Saitama Prefecture 1-297, Mitsubishi Materials Corporation Cement Research Institute F-term (reference) 2D040 AA04 AB01 AC01 AC05 BA00 CB03 CD02 DA01 4G035 AB43 AE13 4G036 AB23 4G065 AA01 AA10 AB01Y AB02Y AB22Y AB38Y BA07 BA20 BB01 BB06 CA11 DA03 FA01 FA01 FA01 CA05 CB08 CC04

Claims (8)

[Claims] In a method for producing a suspension by dispersing a powder in water, the powder is dispersed by ultrasonic waves during and / or after mixing of the powder and water, and then the powder is aggregated. A method for producing a suspension, comprising removing lumps from the suspension. 2. The method according to claim 1, wherein the powder is an inorganic hydraulic material powder, and the suspension comprises 0.5 to 5.0% by weight of a dispersant based on the powder. A method for producing a suspension, comprising: 3. The method for producing a suspension according to claim 1, wherein the aggregate is removed by a cyclone. 4. The method for producing a suspension according to claim 1, wherein the aggregates are removed by a centrifuge. 5. The method for producing a suspension according to claim 1, wherein the aggregates are removed by sedimentation. 6. A method of injecting a suspension in which powder is dispersed in water into an injection object using a pipe, wherein the suspension is injected while applying ultrasonic waves. Injection method. 7. The method according to claim 6, wherein the powder is an inorganic hydraulic material powder, and the suspension contains 0.5 to 5.0% by weight of a dispersant based on the powder. A method for injecting a suspension, comprising: 8. The method according to claim 6, wherein ultrasonic waves are applied to a suspension outlet of the pipe.