JP2903375B2 - Method and apparatus for producing injection liquid for ground consolidation and ground injection method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is for soil consolidation in which a suspension containing ground consolidation powders having different particle diameters is classified and sorted into a distribution state corresponding to the particle diameter to obtain a plurality of injection liquids. Manufacturing method of infusion liquid,
The present invention relates to a manufacturing apparatus for the injection liquid and a ground injection method for injecting the injection liquid into the ground to consolidate the ground. The present invention relates to a method and an apparatus for manufacturing an injection liquid for ground consolidation to obtain a liquid, and a ground injection method using the injection liquid.

[0002]

2. Description of the Related Art When injecting a grout into a ground to consolidate the ground, a suspension grout or a permeation grout is generally known as the grout.

[0003] Among them, the suspension type grout has high strength but poor permeability, and the solution type grout has good permeability but low strength.

For this reason, conventionally, suspended grout is usually used for coarse-grained soil layers and soft layers having large voids.
For the fine-grained soil layer, a solution-type permeable grout having a long gelation time was used.

[0005] In order to improve the permeability of the above-mentioned suspended grout as much as possible, it has been considered to make the ground consolidating powder in the grout finer.

Meanwhile, it is generally said that the consolidation strength or permeability of the ground consolidation liquid is greatly affected by the distribution of the particle size of the ground consolidation powder present in the liquid. That is, the consolidation strength and permeability of the injection liquid are improved by reducing the distribution width of the particle diameter of the powder present in the injection liquid.

For example, a suspension having an average particle size of 5 μm is 10 μm
Of course, those that cut the above particles have better permeability, but cut particles of 10 μm or more, and
A suspension obtained by cutting particles of 2 μm or less has better permeability to fine-grained soil.

Therefore, various attempts have been made in the past to produce an injection solution having such a narrow particle size distribution width. One example of this is a method of collecting the supernatant of the suspension, specifically, stirring a suspension containing powder such as calcium carbonate, cement, and slag together with a deflocculant. A method has been proposed in which, after mixing, the mixture is allowed to stand in a settling tank for a predetermined time to settle large particles, and then the supernatant is removed.

[0009]

According to this method, in the case of a powder having a relatively small specific gravity such as calcium carbonate, a liquid distribution according to the particle size of the powder is possible. However, in the case of powder having a relatively large specific gravity, such as cement or slag, the solid content (powder) in the suspension settles in a short time in the settling tank and becomes a supernatant. Almost no solid content remains, and therefore, it is difficult to distribute the liquid according to the particle size of the powder.

For this reason, in this case, even if the liquid level in the sedimentation tank and the timing of liquid separation are adjusted, the suspension having a predetermined particle size distribution and sufficient strength as an injection liquid can be obtained. No liquid is obtained.

Moreover, in the above-mentioned method, not only is the operation of extracting the supernatant liquid from the sedimentation tank troublesome, but also at the time when the suspension is allowed to stand and the powder having a large particle diameter is settled, There is a problem that the injecting operation is restricted by the settling time because the supernatant liquid above the predetermined level is taken out.

That is, in the actual injection operation, the injection liquid must be continuously prepared according to the injection speed. However, in the above-described method, the injection is restricted by the waiting time for sedimentation.

Accordingly, an object of the present invention is to prepare a plurality of injection solutions by classifying and separating a suspension containing ground consolidating powders having different particle sizes into a distribution state corresponding to the particle size. It can be prepared in a short time and by a simple operation, and when the obtained injection liquid is injected into the ground, it has excellent permeability and can exhibit high compaction strength, which has solved the above-mentioned disadvantages of the known art. It is an object of the present invention to provide a method for producing an injection liquid for ground consolidation, an apparatus for producing the injection liquid, and a ground injection method using the injection liquid.

[0014]

In order to achieve the above-mentioned object, according to the method for producing a ground consolidation injection liquid of the present invention,
The suspension containing the ground consolidation powders having different particle diameters is classified in a classification tank, particularly under a fluidized state, into a distribution state according to the particle diameter of the powder, and then the classification is performed from the classification tank. Each of the obtained suspensions is fractionated to produce a plurality of injection solutions containing ground consolidation powders having different particle diameters.

Further, in order to achieve the above-mentioned object, according to the apparatus for producing a ground consolidation injection liquid of the present invention, a suspension containing ground consolidation powders having different particle diameters is filled and the suspension is filled. A classification tank provided with equipment for maintaining the suspension in a fluidized state, a plurality of storage tanks for separating and storing suspensions having different particle size distributions from the classification tank, and the storage tank and the classification tank And a conduit provided with a valve and communicating with each other.

Furthermore, in order to achieve the above-mentioned object, according to the apparatus for manufacturing a ground consolidation injection liquid of the present invention, a suspension containing ground consolidation powders having different particle diameters is filled and the suspension is filled. A classification tank provided with equipment for maintaining the suspension in a fluidized state, and a separation tank that is connected to the classification tank and a conduit equipped with a valve, and separates suspensions having different particle size distribution states, A storage tank that is communicated with the classification tank, a conduit provided with the classification tank and a valve, and that separately stores the suspension in the classification tank from the classification tank and stores the separation tank and a valve; And a storage tank for separating and storing the separated suspension in the separation tank from the separation tank.

Furthermore, in order to achieve the above-mentioned object,
According to the ground injection method of the present invention, the suspension containing the powder for ground consolidation having different particle diameters is classified into a distribution state according to the particle diameter of the powder in a classification tank, and then the classification is performed. Each of the suspensions is dispersed to form a plurality of ground consolidation infusions having different particle diameters, and one or a plurality of the prepared infusions are injected into the ground.

[0018]

DETAILED DESCRIPTION OF THE INVENTION The ground consolidating powder used in the present invention is, for example, slag, cement, calcium carbonate, lime, gypsum, pozzolans (fly ash, silica fume, white carbon, clay, diatomaceous earth, acid clay, etc.). ), Etc., which are used alone or in combination.

Each of these powders is formed of particles having a different particle size. For example, taking slag as an example, this usually has a specific gravity of 2.85 to 2.94, a Blaine specific surface area of 3500 to 4400 cm ² / g, a maximum particle diameter of 48 to 150 μm, an average particle diameter of 10 to 16 μm, and 10 μm 33-50% below, 44
The μm residue is 0.8-15.3% (average 8.9%). The average particle diameter of the particles having a specific surface area of 8000 to 15000 cm ² / g is 2 to 5 μm, and 90 to 1 μm or less is 90 to 1 μm.
00%.

When these powders are pulverized into fine particles,
Since the overall particle size is reduced, the average particle size is surely reduced, but the width of the particle size distribution generally does not substantially change.

It is relatively easy to atomize ordinary slag powder (blaine specific surface area: 3500 to 4400 cm ² / g) to the vicinity of 8000 cm ² / g of brane specific surface area. Is extremely expensive to manufacture. In addition, the product itself contains a lot of air, which makes packaging, transportation, and handling on site difficult, and the finer the particles, the more easily they are electrically aggregated, and conversely, the effect of inhibiting permeation is produced.

The ground consolidating powder is suspended in a liquid such as water to obtain the suspension according to the present invention. The suspension further contains water glass, colloidal silica,
An alkali reactant (sodium aluminate, water-soluble alkali, etc.) can also be included.

In the present invention, the above-mentioned suspension is placed in a classification tank.
Classification and fractionation are performed while maintaining a fluidized state by stirring, aeration, circulation, or a combination thereof.
Specifically, it is as described later.

The plurality of ground consolidation infusions prepared as described above are injected into the ground independently or in combination. Further, these infusions are obtained by treating one or more of these with water glass, an alkali solution, and colloidal silica obtained by treating water glass with an ion exchange resin.
Alternatively, it may be mixed with an acidic silica sol, further mixed with a gelling agent or an auxiliary such as lime or sodium bicarbonate and injected into the ground.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

FIGS. 1 and 2 are schematic views showing a specific example of a manufacturing apparatus of one type according to the present invention, and FIGS. 3 and 4 are specific examples of a manufacturing apparatus of the other type according to the present invention. FIG.

First, one type of manufacturing apparatus is shown in FIG.
Referring to FIG. 2, reference numeral 1 denotes a classification tank,
A suspension 2 containing ground consolidation powders having different particle sizes is filled therein. The suspension 2 is prepared in the classification tank 1 by charging the powder into the classification tank 1 charged with water, and then operating the stirrer 3 or the air compressor 4 provided in the classification tank 1 to mix the powder sufficiently. However, it may be prepared outside the classification tank 1.

The ground consolidation powder in the suspension 2 includes slag, cement, calcium carbonate, lime,
Gypsum, pozzolans and the like. These are used alone or in combination of two or more. In addition, suspension 2
The powder is easily dispersed by containing a small amount of a flotation reagent such as a deflocculant such as a melamine resin, a naphthalene compound, or a polyphosphate salt, or a foaming agent, a collecting agent, an activator, or a dispersant. , Good suspension.

Next, when the above-mentioned suspension 2 is placed in the classification tank 1 under weak stirring by the stirrer 3 or under weak ventilation by the air compressor 4, the powder for ground consolidation in the suspension 2 becomes fine particles. Those having a diameter (2a), that is, those having a low specific gravity, stay at the upper side, and those having a coarse particle diameter (2b), that is, those having a high specific gravity, settle down and move according to the size of the particle diameter. . As a result, in the classification tank 1, a suspension having a distribution state in which the particle diameter of the powder gradually increases from above to below is formed.

In FIG. 1, reference numerals 9 and 11 denote storage tanks, and these storage tanks 9 and 11 are each provided with a conduit 12 provided with a valve 7.
And a classification tank 1 through a conduit 13 provided with a valve 8.
By being connected to a conduit 14 provided with a valve 6 at the bottom of the tank, the tank is in communication with the classification tank 1 at the bottom. The valve 6 is normally in a closed state, but after a suspension having a distribution having a different particle size is formed in the classification tank 1 as described above, a sensor built in the controller 5 (the same applies hereinafter). And the valve 7 is opened together with the valve 7, and at the same time, the valve 8 is closed, and the lower suspension 2 in the classification tank 1, that is, the suspension 2 having a coarse particle size is distributed to the storage tank 9. .

Eventually, the liquid level 2 c of the suspension 2 in the classification tank 1
When the robot reaches the tip 10a of the electromagnetic rod 10, the controller 5
In response to this information, the valve 7 is closed and the valve 8 is opened at the same time, and the upper suspension in the classification tank 1, that is, the suspension 2 having a fine particle size is distributed to the storage tank 11. As a result, the suspension 2 in the classification tank 1 is sequentially taken out from the bottom of the classification tank 1 into separate storage tanks 9 and 11 and separated. In this case, the relationship between the predetermined depth from the liquid surface and the particle size distribution and solid content concentration during this period is checked in advance. Electromagnetic rod 10
Are arranged so that the tip 10a is located at that depth.

The sensor incorporated in the controller 5 detects the degree of classification of the suspension. As a method for this, in addition to the arrangement of the above-described electromagnetic rod 10, the following may be considered.

(1) Method Using a Timer After the suspension 2 in the classification tank 1 is stirred by the stirrer 3 at a predetermined number of revolutions, the stirring is interrupted, and the time required for classification and the amount of the separated suspension are measured. If the relationship between the particle size distribution and the solid content concentration of the powder in the suspension is checked in advance, the classification can be performed by performing a valve operation for a predetermined time.

(2) Method of Measuring the Weight of the Suspension in the Classification Tank The suspension is continuously discharged while measuring the weight of the suspension in the classification tank, and the discharge is interrupted when a predetermined weight is reached. In this way, fractionation is performed. For example, a density meter such as a radioisotope is installed in a classification tank, and when the density of the suspension at a predetermined height exhibits a predetermined value, a predetermined amount of the suspension can be discharged to separate the suspension. .

(3) Concentration detection method A suspension is sampled from a viewing window or a bypass tube provided in a classification tank, and the concentration of the suspension is measured by an absorbance meter. The valve is operated on the basis of the measured value to collect the suspension.

Therefore, a suspension (injection liquid) containing the powder having a coarse particle diameter is separated into the storage tank 9, and a suspension containing the powder having a fine particle diameter is stored in the storage tank 11. The suspended liquid (injection liquid) is separated to produce a plurality of ground consolidation injection liquids having different particle sizes. In FIG. 1, 15 and 16 are valves, respectively.

As described above, the suspension 2 may contain one or more of water glass, an alkali, a reactant and the like in addition to the ground consolidation powder. These water glass, alkalis, reactants and the like are contained not only in the suspension 2 in the classification tank 1 but also in the ground consolidation injection liquid in the storage tanks 9 and 11 separated from the classification tank 1. Is also good.

As the above-mentioned water glass, No. 3 water glass,
Water glass with a lower molar ratio than this, or water glass with a higher molar ratio than this, may be mentioned, and as the alkali, caustic soda, cement, slaked lime, etc. may be mentioned. Alkaline salts such as alkali metal salts of soda, carbonic acid and bicarbonate.

FIG. 2 shows a modification of the apparatus of FIG. 1, in which the storage tank 1 is connected to the side wall 1a of the classification tank 1 via conduits 19 and 20, respectively.
7, 18 and at the bottom via conduit 14
Is communicated with. The conduit 14 is provided with the valve 6 as described above,
The conduit 19 comprises valves 21a, 21b, 21c, respectively,
20 is provided with a valve 22.

When separating the suspension, first, the valve 22
Only, with the others closed, the upper part of the classification tank 1 is introduced into the storage tank 18 via the conduit 20 and then the valves 21a,
21b and 21c are opened, and the other part is closed and the intermediate part in the classification tank 1 is introduced into the storage tank 17 through the conduit 19, and each part in the classification tank 1 is sequentially operated from the uppermost part by a valve operation. Separate into storage tanks. And the bottom is Fig. 1.
Similarly to the above, only the valve 6 is opened from the bottom of the classification tank 1, and the other is closed and introduced into the storage tank 9 through the conduit 14 for separation, but similar to the above, although not shown, separation from the side wall is also possible. Absent.

The classifying tank 1 can be of any shape, but in particular, as shown in FIG. 5, it has an inverted conical shape so that the particle size distribution differs. It is preferable in forming a suspended suspension. In FIG. 2, reference numerals 31 and 32 denote valves.

Next, the other type of manufacturing apparatus will be described with reference to FIGS. 3 and 4. FIG.
In the same manner as described above, the suspension 2 containing the ground consolidation powder having a different particle size is filled. The suspension 2 can also be prepared in the classification tank 1 by operating the stirrer 3 and the air compressor 4 provided in the classification tank 1 as in FIG. Needless to say, the suspension 2 may contain the above-described peptizer, flotation reagent, and the like, as in FIG.

The above-mentioned suspension 2 is supplied to the classification tank 1 as in FIG.
In the inside, the stirrer 3 and the air compressor 4 are slowly operated to form a suspension in a distribution state in which the particle diameter gradually increases from above to below.

Reference numeral 23 denotes a separation tank, which communicates with an arbitrary part of the side wall 1a of the classification tank 1 at an arbitrary part of the side wall 23a through a conduit 25 provided with a valve 24, as shown in FIG. Or at the bottom, as shown in FIG.
And a conduit 27 provided with a valve 26.

Furthermore, the classification tank 1 is connected at the bottom to the storage tank 9 via a conduit 14 provided with a valve 6, and the separation tank 13 is also provided via a conduit 29 provided at the bottom with a valve 28. It is communicated with the storage tank 30. In FIGS. 3 and 4, 33
Is a valve.

In the manufacturing apparatus of the type having the above configuration,
In the case of the configuration shown in FIG. 3, upon receiving information from the controller 5, first, the valve 6 and the valve 28 are closed,
And, the valve 24 is opened, and the suspension above the conduit 25 in the classification tank 1, that is, the suspension 2 a in which the powder having a small particle size is distributed, is passed from the classification tank 1 to the separation tank 23 through the conduit 25. Introduce and separate. 34 is a stirrer.

Next, the suspension 2 remaining in the classification tank 1, that is, the suspension 2 in which the powder having a large particle size is distributed,
Upon receiving the information from the controller 5, the valve 6 is opened,
The suspension 2a, which is separated into the storage tank 9 through the conduit 14 and in which the powder having a small particle size in the separation tank 23 is distributed, receives the information from the controller 5, the valve 28 is opened, and the conduit 29 is opened.
Through the storage tank 30.

Although FIG. 3 shows an example in which one separation tank 23 is provided, a plurality of the separation tanks are provided, and a plurality of suspensions in which powders having different particle sizes are distributed are stored in each storage tank. It can be introduced and separated.

In the case of the configuration shown in FIG. 4, upon receiving the information from the controller 5, first, the valve 6 and the valve 28 are closed, and the valve 26 is opened, so that the lower suspension in the classification tank 1 The liquid, that is, the suspension 2b in which the powder having a large particle size is distributed is separated from the classification tank 1 through a conduit 27 into a separation tank.
Introduce to 23 and separate.

Next, the suspension 2 remaining in the classification tank 1, that is, the suspension 2 in which the powder having a small particle size is distributed receives the information from the controller 5, the valve 6 is opened, and the conduit 14 is opened. The suspension 2b, in which the powder having a large particle size is distributed in the separation tank 23, receives the information from the controller 5, the valve 28 is opened, and the storage tank 30 is passed through the conduit 29. Is separated into

Although FIG. 3 shows an example in which the size of the classification tank 1 and the size of the separation tank 23 are the same, these are not necessarily the same, and as shown in FIG. May be smaller than the classification tank 1. As described above, it is preferable that the classification tank 1 has an inverted conical shape in order to form a suspension having different particle size distributions.

FIG. 6 is an explanatory view showing a modification of the classification tank 1 according to the present invention. In FIG. 6, when the suspension 2 in the classification tank 1 is placed in a fluidized state under weak stirring by the stirrer 3 or under weak ventilation by the air compressor 4, the ground consolidation powder in the suspension 2 becomes granular. The suspension is moved in accordance with the size of the diameter, and classified into a plurality of suspensions in a distribution state in which the particle diameter of the powder gradually increases from above to below.

The classified suspension is supplied through a suction tube 35.
By operating the suction pump 36, suction is performed from below, and the liquid is dispensed into storage tanks (not shown) to form an infusate. 37 is a valve.

In the present invention, as shown in FIG. 7, the suspension 2 in the classification tank 1 is circulated by a circulation pipe 40 having an outlet 38 below and an inlet 39 above. By operating and circulating the circulating pump 41 disposed in the circulating pipe 40, the fluidized state can be maintained. In FIG. 7, 42 and 43 are valves.

Further, in the present invention, as shown in FIG. 8, the suspension 2 in the classification tank 1 has an outlet 38 and an inlet 39 at substantially the same height on the opposite side walls of the classification tank 1. Each of the circulation pipes 40 has
The fluid state may be maintained by activating and circulating the circulation pump 41 arranged in the circumstance.

FIG. 8 is a flow sheet showing an example of a ground injection method using an apparatus for producing an injection liquid for ground consolidation by this type of circulation system.

First, a suspension 2 containing one or more of slag, cement, calcium carbonate, lime, gypsum, pozzolans and the like is prepared in a mixing vessel 44. This mixing container
The suspension 2 in 44 may contain a reactant such as water glass, colloidal silica, alkalis such as caustic alkali, and sodium aluminate.

The suspension 2 in the mixing vessel 44 is then loaded into the classification tank 1 from the bottom of the classification tank 1 via conduits 45, 46, 47 by the operation of the air compressor 4 or from the circulation pipe 40. You. 48, 49, and 50 are valves. These valves 48, 49, and 50 are communicated to the controller 5 together with the air compressor 4, and receive the information from the controller 5 to open and close the valves 48, 49, and 50, or to operate the air compressor 4 to operate the suspension 2. Loading into the classification tank 1 is automatically operated.

The suspension 2 charged in the classification tank 1 is circulated through the circulation pipe 40 from the outlet 38 to the inlet 39 by the operation of the circulation pump 41, and maintains a fluid state. At this time,
The powder in the suspension 2 is classified into a distribution state according to the particle size while floating, and the classified suspension above the classification tank 1 is passed through the conduit 49 from the valve 49 of the circulation pump 41 to the storage tank. The suspension distributed in the classification tank 1 and classified below the classification tank 1 is distributed from the valve 50 at the bottom of the classification tank 1 to the storage tank 9 through the conduit 52.

The valves 49 and 50 are connected to the controller 5 together with the circulating pump 41, respectively.
In response to the information from, the dispensing of the suspension 2 into the storage tanks 9 and 52 is automatically operated by opening and closing the valves 49 and 50 or by operating the circulation pump 41. In FIG. 8, the stirrer 3 may be used in addition to the circulation operation described above.

The suspensions collected in the storage tanks 9 and 52 are guided to the valve 56 of the conduit 55 by the operation of the pumps 53 and 53, respectively, merged and injected into the ground 58 through the injection pipe 57.

The above-mentioned combined suspension is mixed with water glass, alkali solution, colloidal silica, acidic silica sol, etc. obtained by treating water glass from a storage tank 59 connected to a conduit 55 with an ion exchange resin. It may be mixed in conduit 55 and injected into the ground, and furthermore a storage tank connected to conduit 55
Gelling agent such as baking soda and lime from 60, various auxiliaries and conduit 55
And mixed into the ground.

The above-mentioned suspension according to the present invention contains ground consolidation powder such as slag, cement, calcium carbonate, gypsum, pozzolans (fly ash, silica fume, white carbon, clay, diatomaceous earth, acid clay, etc.). This is as described above.

Of these, cement hardens by itself, so it is sufficient to classify and dispense the suspension, and then inject each. However, since other suspensions do not harden by themselves, it is necessary to add a reactant. There is. Of course, these can be used as a reactant to cure other materials, but here, other materials that react with the suspension are referred to as reactants.

Although the slag does not solidify by itself, it exhibits water glass, particularly a low-molar-ratio water glass, a silica colloid solution obtained by removing most alkali by passing water glass through an ion exchange resin, and exhibits alkalinity. Potential hydraulic properties are stimulated and hardened by adding salts such as sodium aluminate, sodium bicarbonate, sodium carbonate, alkalis such as caustic, lime, cement and the like. The activity of the slag is improved by making the slag into fine particles, and the reactivity with water glass or alkali increases.

Although pozzolans do not cure by themselves,
When mixed with lime or slag in the presence of alkali, silica is eluted and gelled.

As the slag, any blast furnace slag, a mixture of slag and cement, and the like can be used, and calcium silicate can also be used.

As the reactant, an acid, salt, glyoxal, ester such as polyhydric acetic acid ester, ethylene carbonate, etc., a reactant such as an organic salt, an organic acid, etc., which react with water glass, and water glass are passed through an ion exchange resin to form an alkali. Can be used.

The ground consolidating powder according to the present invention is classified into a distribution state according to the particle size by the above-described classification operation. The particle size distribution in each fractionated suspension is smaller than the particle size distribution width of the original powder. The obtained suspension may be used as it is, or water glass, alkali (caustic soda, sodium aluminate, sodium carbonate, sodium bicarbonate, sodium phosphate, etc.), colloidal silica (most of alkali in water glass by ion exchange resin). By mixing with stable colloidal silica obtained by removal, acidic silica sol (strongly acidic stabilized silica sol obtained by mixing acid and water glass) and various curing agents,
Injections (grout) with different gelation times and consolidation strengths. By using these grouts together, complex ground can be effectively consolidated.

According to the present invention, as described above, the ground consolidation powder is classified and fractionated as suspensions having different consolidation characteristics and fluidity, so that these suspensions can be used alone or in combination. Effectively exhibits appropriate strength and permeability to complex ground. Further, in the present invention, the powder is classified and sorted into distributions having different average particle diameters, so that no waste occurs.

In the present invention, for example, when a slag having a Blaine specific surface area of 4000 cm ² / g is classified, a specific surface area of
Suspensions with excellent reactivity, equivalent to 00 cm ² / g, are easily prepared. When the slag having a specific surface area of 8000 cm ² / g is classified, the specific surface area which can penetrate the standard sand is 1%.
An ultrafine slag suspension of 0000 cm ² / g or more is obtained. Further, when the ultra-fine particle slag having a specific surface area of 10,000 cm ² / g or more is classified, a suspension mixed with silt and penetrating into sand is obtained.

[0072]

According to the present invention, a suspension containing a ground consolidating powder having a different particle size is filled in a classification tank provided with a stirring mechanism, a ventilation mechanism or a circulation mechanism. Actuation maintains the suspension in a fluid state. Due to this flow, the powder in the suspension becomes a floating state, and is classified into a plurality of distribution states according to the particle size.

The classified suspension described above is then separated directly into a storage tank or into a storage tank via a separation tank to obtain a plurality of injection solutions containing powders having different particle sizes. By this classification operation, the powder is classified according to the particle size, and the particle size distribution width is reduced.

Generally, particles dispersed in a fluid are subjected to resistance to flow and buoyancy due to the fluid in addition to gravity and centrifugal force. Thus, the rate of separation of the particles, ie, the rate of settling in the suspension, is determined by the balance of these several forces. That is, in the present invention, based on the principle that the larger the particle size and the higher the specific gravity of the particles, the higher the sedimentation speed, the lower the specific gravity of the particles in the fluidized state of the suspension, and the lower the sedimentation of the heavy particles. Let it. Furthermore, classification based on the particle size occurs at the same time as classification based on the specific gravity, and even light particles having a large particle diameter settle out, and fine particles float even with heavy particles.

In general, the finer the particle size of the ground consolidation powder, the better the permeability, but the lower the consolidation strength. on the other hand,
The chemical or electrical reaction is activated as the particle size becomes smaller. In addition, the permeability is improved as the particle size distribution width is reduced and the particle size is reduced. When the particle size distribution width is large, even if the average particle size is small, particles having a large particle size are in a ruled stage and can prevent penetration. Small particles electrically aggregate with each other or around large particles, impairing permeability.

When the powder is classified and the particle size distribution width is reduced, the permeability is improved. This is presumably because the coagulation effect of the fine particles present in the original powder can be prevented. Therefore, the smaller the particle size distribution width, the more excellent the permeability even if the average particle size is large. Further, when a plurality of injection solutions obtained by classification are superimposed, superior permeability is exhibited as compared with injection of the injection solution before classification without any change. A homogeneous body excellent in strength can be obtained.

[0077]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail.

1. Materials used (1) Slag Three types of granulated slag having the average particle size, the specific surface area of the brane, and the width of the particle size distribution shown in Table 1 were used. FIG. 9 shows the relationship between these three types of particle diameters (μm) and the transmittance.

[0079]

[Table 1]

Here, the average particle size is such that the cumulative value of the particle size distribution is 50.
%, Ie, the median diameter, and the particle size distribution width is 2.5% for each of the upper and lower parts of the distribution.
Indicates the range of particle size that accounts for 95%.

(2) Water Glass Various water glasses having a molar ratio of about 4.0 to 1.0 can be applied. Here, two types of water glass shown in Table 2 were used.

[0082]

[Table 2]

(3) Cement Portland cement having a specific surface area of brane of 8600 cm ² / g and an average particle size of 8.2 μm was used.

(4) Sodium hydrogencarbonate Primary reagent (NaHCO ₃ ) was used.

(5) Slaked lime Fine calcium hydroxide having an average particle size of 8 μm was used.

(6) Sodium aluminate solution A sodium aluminate solution having the following composition was used. Na ₂ O: 22.47%, Al ₂ O ₃ : 1.59%

2. Slag classification test (1) A slag classification test was performed using the classification tank 1 shown in FIG. The slag used was the sample No. 1 in FIG. First, 250 l of water was put into the classification tank 1, 150 kg of the slag was put into the tank, and the mixture was sufficiently dispersed and suspended by the stirrer 3. After that, the controller 5 detected the degree of classification by measuring the turbidity of the suspension while maintaining weak stirring.

After leaving for several minutes according to the classification degree by the turbidity measurement, the valve 6 is automatically opened according to the instruction of the controller 5, and four kinds of suspensions according to the particle size distribution state are prepared.
That is, the particles were sorted into different storage tanks sequentially from the lower layer to the upper layer, starting from the one having the largest particle size.

The suspensions a, b, c and d are sequentially arranged from the lowermost layer.
FIG. 10 shows the relationship between the particle diameter and the passage rate. Further, comparison was made between these a, b, c, d, and the raw slag (sample No. 1 in FIG. 9), and the results are shown in Table 3.

[0090]

[Table 3]

(2) A slag classification test was performed using the classification tank shown in FIG. The slag used was sample No. 2 in FIG. First, 250 l of water was put into the classification tank 1, 150 kg of the slag was put into the tank, and the mixture was sufficiently dispersed and suspended by the stirrer 3. After that, the controller 5 detected the degree of classification by measuring the absorbance of the suspension while maintaining weak stirring.

According to the classification degree obtained by the spectrophotometry,
After standing for several minutes, the valve 24 was automatically opened according to the instruction of the controller 5, and the fine particle suspension was automatically transferred to the separation tank 23 through the conduit 25, and was then collected in the storage tank 11. This sample was designated as Sample C.

As a result, the coarse particle suspension remains in the classification tank 1. This residual suspension was further classified into two types, a medium particle suspension and a coarse particle suspension, using the electromagnetic rod shown in FIG. 1 and separately classified into storage tanks. The sample in the lowermost layer was designated as A, and the medium particle suspension sample thereon was designated as B.

FIG. 11 shows the relationship between the particle size (μm) of each of Samples A, B and C and the transmittance (%). Further, a comparison was made between Samples A, B, and C and the raw slag (Sample No. 2 in FIG. 9), and the results are shown in Table 4.

[0095]

[Table 4]

(3) A slag classification test was performed using the classification tank shown in FIG. As the slag, that of sample No. 3 in FIG. 9 was used. First, 250 l of water was put into the classification tank 1, 150 kg of the slag was put into the tank, and the mixture was sufficiently dispersed and suspended by the stirrer 3. Thereafter, the suspension was classified into a distribution state according to the particle size while maintaining weak stirring.

Next, sampling was performed from each of the classified layers, and their densities were measured to confirm the degree of classification. Thereafter, the liquid surface of the suspension was pressurized with air, and the suspension was fractionated into an upper layer (fine particle suspension), an intermediate layer, and a lower layer (coarse particle suspension) by a suction tube 35. Suspensions of I, B and C were obtained from the lower layer, respectively.

FIG. 12 shows the relationship between the particle diameters of these samples A, B, and C and the transmittance. Furthermore, these samples A, B, C, and raw slag (Sample No. 3 in FIG. 9) were compared,
Table 5 shows the results.

[0099]

[Table 5]

From the above, the suspension is separated from a layer having a large particle size into a layer having a small particle size. The width of the particle size distribution of each of the separated layers is extremely smaller than that of the original slag, and the suspension of the slag having a uniform particle size is obtained. It can be seen that a suspension was obtained.

3. Combination test Using each suspension fractionated in the above fractionation test and the raw slag as a control, tests were conducted with various formulations.

(1) The suspension shown in Table 3 (FIG. 10) was used. Tests were performed on a system consisting of a suspension containing the water glass of No. 2 in Table 2 and the slag of Table 3 and sodium bicarbonate or slaked lime. Table 6 shows the results.

The gel time was measured by a cup inverted method. The unconfined compressive strength was measured for a sandgel obtained by mixing and filling the Toura standard sand and the compounding liquid in a mold in accordance with the Japan Society of Soil Engineering Standard "unconfined compression test method for soil". Ten
The day strength indicates the strength of a product cured in a mold for 10 days, and the 50-day strength indicates the strength of a product cured in a mold for 10 days and then cured in water for 40 days. On the 100th day, the intensity for one year is the same as above.

[0104]

[Table 6]

From Table 6, it can be seen that in Examples 1, 6, 11, and 16 using raw slag having a large particle size distribution,
It can be seen that the compaction strength is small in spite of the short gelation time as compared with Nos. 2 to 5, 7 to 10, 12 to 15, and 17 to 20.

It should be particularly noted that, in the system according to the present invention, even when the average particle size of the slag is larger than the average particle size of the raw slag, the gelation time is long and the consolidation strength is large. I understand.

(2) The suspension shown in Table 4 (FIG. 11) was used. Table 4
The original slag is very small in both the average particle size and the particle size distribution width as compared with the original slag in Table 3 above. Therefore, the fractionated slag is also very small in both the average particle size and the particle size distribution width. A test was conducted on a system consisting of the suspension containing the slag, the water glass No. 2 in Table 2, and a sodium aluminate solution. Table 7 shows the results. The gel time and the uniaxial compressive strength were measured as described above.

[0108]

[Table 7]

As is clear from Table 7, in this experiment,
It shows the same tendency as in Table 7 described above.

(3) Use the suspension shown in Table 5 (FIG. 12). Table 5
Slag itself is considerably finely divided.
Therefore, both the average particle size and the fineness distribution width are further reduced by the classification operation.

The suspension containing these slags and N in Table 2
A test was conducted on a system consisting of o.1 water glass, cement, and a sodium aluminate solution. Table 8 shows the results. The gel time and the uniaxial compressive strength were measured according to the above.

[0112]

[Table 8]

As is evident from Table 8, all the samples show high consolidation strength. This is because self-hardening cement was used as the cement. In addition, all samples have a short gelation time. The overall tendency is the same as in Tables 6 and 7 described above.

From the above tests, it can be seen that the gelation time is increased and the consolidation strength is increased by reducing the average particle size of the slag and, at the same time, reducing the particle size distribution width by the classification operation. These tests also show that even if the average particle size is large, it is preferable to reduce the particle size distribution width with respect to the gelation time and the consolidation strength. The longer the gelation time, the higher the permeability.

4. Viscosity test As described above, if the gelation time of the grout (injection liquid) is made longer, the time required for permeation is kept longer, which leads to an improvement in permeability. In addition, if the viscosity of the grout is high, the permeability deteriorates. Therefore, here, the viscosity up to gelation of the grout was examined.

Based on the viscosity and gelation time of each sample in Table 6, the elapsed time after blending (the time when gelation was reached was 1,
The time until the gelation was shown by a ratio (ratio). ) Was measured, and the results are shown in the graph of FIG.

The viscosity was measured with a B-type viscometer. In FIG. 13, Examples No. 2 to 5 including the classification slag according to the present invention,
Examples 7 to 10, 12 to 15, and 17 to 20 all fall within the range indicated by the solid line, while Examples Nos. 1, 6, 11, and 16 including the original slag were used.
Then, it was near the broken line.

That is, the slag suspension fractionated by the classification operation according to the present invention is different from that of the raw slag in that
The figure shows that the viscosity up to gelation is kept low.
I understand from 13. This fact indicates that the operation of the present invention achieves an improvement in permeability as well as a delay in the gel time of the suspension (grout).

5. Injection test The grout shown in Table 6 was subjected to an injection test using the injection device shown in FIG. In FIG. 14, 101 is a compressor, and 102 and 103 are pressure gauges. A chemical tank 106 according to the present invention is filled in a water tank 105 provided with a stirrer 104 connected to a compressor 101. An acrylic mold 107 is filled with earth and sand 108.

The injection solution 6 filled in the water tank 105 is introduced into the earth and sand 108 in the acrylic mold 107 by the operation of the compressor 101. Here, the chemical solution 106 is permeated into the earth and sand 108, and the permeated chemical solution 106 is collected in the measuring cylinder 111 and the permeation state is measured. Reference numerals 109 and 110 denote wire meshes. Earth and sand 1 filled in acrylic mold 107
08 was filled with soils of different sizes, large and small, and the injections in Table 3 above were injected alone or in combination, and the results were observed. The injection test was performed as follows.

1. Single injection test The injection solutions of Examples Nos. 1 to 5 shown in Table 6 were individually injected. Table 9 shows the observation results.

[0122]

[Table 9]

In Table 9, Control Example No. 21 is an injection using the original slag, and does not show sufficient penetration not only in the fine part but also in the coarse part. Example No. 22 is clearly better in permeability than Example No. 21, though the average particle size is much larger than Example No. 21 above. Example No.2
The samples Nos. 3 and 24 have an average particle diameter substantially equal to that of Example No. 21, but are far superior to Example No. 21 in permeability. From this, it is confirmed that not only the average particle size of the powder but also the particle size distribution width greatly affects the permeability.

[0124] 2. Combined injection test Example 21 After the primary injection of the injection liquid of Example No. 2 in Table 6, the injection liquid of Example No. 4 in Table 6 was used as the secondary injection liquid and injected in the same amount as the primary injection liquid. As a result, permeation was sufficiently permeated from the coarse portion to the fine portion, and a uniform and strong compact was obtained as a whole.
In addition, when the No. 2 injection solution and the No. 4 injection solution were mixed and injected at once, the permeability was lower than that of the above-described superposition injection.

Example 22 After the primary injection of the injection liquid of Example No. 3 in Table 6, the injection liquid of Example No. 5 in Table 6 was injected as the secondary injection liquid in the same amount as the primary injection liquid. As a result, the same or better effects as in Example No. 21 were obtained. No.3 and No.5
When the injection liquids were mixed and injected at once, the permeability was inferior to that of the above-described superposition injection.

Example 23 A mixture prepared by mixing equal amounts of the injection solutions of Examples No. 2 and No. 3 in Table 6 was injected as a primary injection solution.
A mixture obtained by mixing the same amounts of the injection solutions of o.4 and No.5 was injected as a secondary injection solution. As a result, an effect equivalent to that of the example 22 was obtained.

Further, a mixture obtained by mixing equal amounts of the injection solutions of Examples No. 2, No. 3, No. 4, and No. 5 was injected at a time. This injection amount is the total amount of the above-mentioned primary injection amount and secondary injection amount. As a result, substantially the same value as in Example 21 was obtained.

As described above, the suspension fractionated by the classification according to the present invention is used as a material for consolidation in the compound injection method so as to be compatible with various types of soil layers and used effectively without waste. Can be.

[0129]

The present invention described above has the following effects. 1. It is easy to adjust the gel time, especially the long gel time. 2. A high-strength suspension grout can be obtained. 3. Even though the average particle size is large, it exhibits excellent permeability instead. 4. If the average particle size is further reduced, more excellent permeability can be exhibited. 5. Since it is excellent in both permeability and strength, it is effective not only for injection into coarse soil layers but also particularly fine soil layers. Therefore, the most suitable effect can be expected as a general chemical solution injection method, particularly as a loosely-coupled grout of compound injection. 6. If the coarse injection material obtained by classification is used as the primary injection material, and the fine injection material is used as the secondary injection material, it is possible to obtain a superior effect, rather than injecting without classification, or injecting only one of them, And all materials can be used without waste.

[Brief description of the drawings]

FIG. 1 is a schematic view illustrating a specific example of a manufacturing apparatus according to the present invention.

FIG. 2 is a schematic view showing another specific example of the manufacturing apparatus according to the present invention.

FIG. 3 is a schematic view showing a specific example of another type of manufacturing apparatus according to the present invention.

FIG. 4 is a schematic view showing another specific example of the manufacturing apparatus of the type shown in FIG. 3 according to the present invention.

FIG. 5 is a schematic view of a specific example of a classification tank used in the present invention.

FIG. 6 is a schematic view of another embodiment of a classification tank used in the present invention.

FIG. 7 is a schematic view of still another embodiment of a classification tank used in the present invention.

FIG. 8 is an explanatory diagram of a ground injection method using a specific example of the manufacturing apparatus according to the present invention.

FIG. 9 is a graph showing a passage rate with respect to a particle diameter of granulated slag.

FIG. 10 is a graph showing a passage rate with respect to a particle diameter of slag contained in a suspension.

FIG. 11 is a graph showing a passage rate of slag contained in a suspension with respect to a particle diameter.

FIG. 12 is a graph showing the passage rate of the slag contained in the suspension with respect to the particle diameter.

FIG. 13 is a graph showing the viscosity of an injection solution with respect to the elapsed time.

FIG. 14 is a schematic diagram of a laboratory injection test device.

[Explanation of symbols]

 1 Classification tank 2 Suspension 3 Stirrer 4 Air compressor 5 Controller 6 Valve 7 Valve 8 Valve 9 Storage tank 10 Electromagnetic rod 11 Storage tank 12 Pipe 13 Pipe 14 Pipe 17 Storage tank 18 Storage tank 19 Storage tank 20 Storage tank 21a Valve 21b Valve 21c Valve 22 Valve 23 Separation tank 24 Valve 25 Conduit 26 Valve 27 Conduit 28 Valve 29 Conduit 30 Storage tank 35 Suction pipe 36 Suction pump 38 Discharge outlet 39 Inlet 40 Circulation pipe 41 Circulation pump

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ identification symbol FI // C09K 103: 00 (58) Field surveyed (Int.Cl. ⁶ , DB name) C09K 17/02 C09K 17/06 C09K 17 / 10 C09K 17/12 E02D 3/12

Claims (13)

(57) [Claims] 1. A suspension containing ground consolidating powders having different particle diameters is classified in a classification tank under a fluidized state into a distribution state according to the particle diameter of the powder, and then the suspension is separated from the classification tank. Producing a plurality of ground consolidation injection solutions each containing a classified suspension and producing a plurality of ground consolidation injection solutions containing ground consolidation powders having different particle diameters; Method. 2. The suspension of claim 1 is stirred and passed in a classification tank.
By air or circulation, or by using them together
2. Classification and sorting while maintaining the fluid state
A method for producing an injection liquid for ground consolidation. 3. The ground consolidating powder is slag or cement.
G, calcium carbonate, lime, gypsum and pozzolans
2. The ground according to claim 1, wherein the ground is one or more types selected from the group consisting of:
A method for producing an infusate for consolidation. 4. The method according to claim 1, wherein the suspension is further added to the powder.
2, water glass, colloidal silica, alkali or reaction
The method for producing an injection liquid for consolidating ground according to claim 1, which comprises an agent. 5. A suspension containing ground consolidation powders having different particle sizes.
Liquid is filled and the suspension is maintained in a fluid state.
Provided classification tank, the distribution state of the particle size from the classification tank
Multiple storage tanks for separating and storing different suspensions,
Provision of a valve that communicates between the storage tank and the classification tank
The suspension is maintained in a fluid state.
Be equipped with a stirrer, ventilator, circulator, or a combination of these
The classification tank is located at the bottom or side wall.
Via multiple storage tanks and conduits each with a valve
And the distribution state of the particle size in the classification tank is changed.
Open the valve from the bottom of the classification tank
Take it out to the storage tank and sort it.
Open the tank, take it out to each storage tank, and separate it.
To manufacture an infusate for ground consolidation. 6. The device according to claim 5, further comprising a controller.
The controller includes a valve and a flow condition.
6. An infusate for ground consolidation according to claim 5 in communication with the equipment to be maintained.
Manufacturing equipment . 7. A suspension containing ground consolidation powders having different particle sizes.
Liquid is filled and the suspension is maintained in a fluid state.
The provided classification tank, and the classification tank and the valve were provided.
Suspensions with different particle size distributions, communicated by conduits
A separation tank for separating the mixture, the classification tank and a valve were provided.
The suspension in the classification tank is communicated by a conduit and the classification is performed.
A storage tank that separates and stores the tank, the separation tank and a valve
Are connected by a conduit provided with
A storage for separating and storing the separated suspension from the separation tank.
And a storage tank for maintaining the suspension in a fluidized state.
If the equipment is a stirring device, a ventilation device, a circulation device, or
A combined device, wherein said separation tank is one or more
With different particle size distribution on the classification tank side wall.
At each location corresponding to each suspension
And is communicated with the classification tank through the bottom of the classification tank,
Connected to the classification tank via a conduit equipped with a valve;
An apparatus for producing an infusion liquid for consolidating ground. 8. The apparatus according to claim 7, further comprising a controller.
Provided, the controller maintains the valve and flow conditions
8. The infusion liquid for consolidating ground according to claim 7,
Manufacturing equipment. 9. A suspension containing ground consolidation powders having different particle sizes.
The liquid was placed in a classifying tank under a fluidized state, depending on the particle size of the powder.
Classify into a distribution state, and then add each of the classified suspensions.
Contained powders for soil consolidation with different particle diameter
A plurality of infusions are prepared, and one of the prepared infusions or
Injecting multiple types into the ground
Construction method. 10. The ground consolidating powder is slag, cement or the like.
G, calcium carbonate, lime, gypsum and pozzolans
10. The ground according to claim 9, which is one or more types selected from the group consisting of:
Injection method. 11. The powder according to claim 9, wherein said suspension is added to said powder.
And water glass, colloidal silica, alkali
10. The method for injecting soil into the ground according to claim 9, wherein the method includes a reactant. 12. The injection liquid for consolidating ground according to claim 9, wherein
Apply one or more of the liquids to water glass, alkaline liquid, water
Colloidal material obtained by treating lath with ion exchange resin
Mixed with silica or acidic silica sol and injected into the ground.
10. The method of injecting soil into the ground according to claim 9, wherein 13. The suspension according to claim 9, wherein the suspension is stirred in a classification tank.
By ventilation or circulation, or by using
10. Classification and sorting while maintaining a fluid state
Ground injection method.