JP3188110B2 - Ground injection method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a suspension comprising a ground consolidating powder consisting of particle size different classified according to the particle size of the powder,
Injection liquid consisting of suspension containing coarse-grained powder for coarse-grained soil layer and soft layer having large voids, and infusion liquid consisting of suspension containing fine-grained powder for fine-grained soil layer Respectively, the present invention relates to a ground injection method that not only rationally solidifies the entire ground but also allows the powder to be used without waste.

[0002]

2. Description of the Related Art When a pouring liquid (grout) is injected into the ground to consolidate the ground, a suspended grout is conventionally used for a coarse-grained soil layer and a soft layer having large voids. In addition, a permeable grout which is a solution type and has a long gelling time was used for the fine-grained soil layer.

[0003]

Problems to be Solved by the Invention In the above-mentioned injection into the fine-grained soil layer, in particular, it has been considered impossible to inject the suspension-type grout because of the required permeability. If a suspension type injection liquid (grout) is to be used for injection into the fine-grained soil layer, the ground consolidation powder contained in the injection liquid should be ultra-fine (powder having a particle size of 10 μm or less). The body must be 100%).

[0004] The above-mentioned ground consolidating powder generally contains many different particle sizes. For example, the slag is specifically described as an example of the powder, and is as follows.

[0005] Normal slag powder has a specific gravity of 2.85 to 2.94,
Specific surface area 3500-4400 cm ² / g, maximum particle size 48-150μ
m, the average particle diameter is 10 to 16 μm, and 10 μm or less is 33 to
It is 50%, and the 44 μm residue is 0.8 to 15.3% (average 8.9%). In addition, the specific surface area is 8000-10000cm ² / g
It has an average particle diameter of 2 to 3 μm.

[0006] It is quite troublesome to pulverize such slag powder and sieve fine powder, especially ultrafine powder.

[0007] It has also been considered that cement as a ground consolidation powder is used as a suspension, and the supernatant is collected and injected. However, it is very difficult to dispose of the remaining sediment and sediment. It has not been put to practical use because it causes troubles of pollution.

Therefore, an object of the present invention is to make a ground consolidation powder having a different particle size into a suspension, and classify the suspension in accordance with the particle size of the powder so that the distribution state of the particle size varies. A plurality of ground consolidation infused liquids consisting of mixed suspensions are manufactured simultaneously, a coarse-grained soil layer or a soft layer having large voids contains an infused liquid containing coarse-grained powder, and a fine-grained soil layer By simultaneously injecting the injection liquid containing the powder having the particle size, not only the entire ground can be rationally consolidated, but also the powder can be used without waste, and the ground in which the above-mentioned disadvantages of the known technique are improved. It is to provide an injection method .

[0009]

According to the present invention, in order to achieve the above-mentioned object, a suspension containing ground consolidating powders having different particle sizes is filled in a classification tank, and the particle size is reduced. Is gradually increased from the top to the bottom, and then the suspensions having different particle size distributions are separated from the classification tank, and the plurality of powders each including the powder having a different particle size are separated. Manufactures ground consolidation infusions and removes coarse soil layers
Injection liquid containing coarse-grained powder in the soft layer with voids,
Injections containing fine-grained powder are applied to the fine-grained soil layer, respectively.
It is characterized by injection, which makes the whole ground reasonable
Not only to solidify but also to use the powder without waste
It is characterized by the following .

[0010] The present invention described above is based on the following apparatus, that is, a suspension in which a suspension containing ground consolidation powders having different particle diameters is filled and the particle diameter gradually increases from the upper side to the lower side. A classification tank for forming a suspension, a plurality of storage tanks for separating and storing suspensions having different particle size distributions from the classification tank, and a valve for communicating each of the storage tanks and the classification tank with a valve. This is done using a device consisting of a closed conduit.

Further, the present invention described above has the following device, namely,
A classification tank that is filled with a suspension containing ground consolidation powders having different particle sizes, and forms a suspension in a distribution state in which the particle size gradually increases from above to below; And a separation tank for separating suspensions having different particle size distributions, and a separation tank for communicating with the bottom of the classification tank to separate and store the lower part of the suspension in the classification tank from the classification tank. Storage tank
The storage is performed using a storage tank that is in communication with the bottom of the separation tank and that stores the separated suspension in the separation tank from the separation tank.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The method of the present invention will be described below in detail with reference to the accompanying drawings.

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

Examples of the ground consolidation powder include slag, cement, calcium carbonate, lime, gypsum, and pozzolans (fly ash, silica fume, white carbon, clay, diatomaceous earth, acid clay, etc.). Are used alone or in combination of two or more. The suspension 2 contains a small amount of a peptizer such as a melamine resin, a naphthalene-based compound, or a polyphosphate-based salt, or a small amount of a flotation reagent such as a foaming agent, a collecting agent, an activator, or a dispersing agent. The body is easily dispersed resulting in a good suspension.

Next, when the above-mentioned suspension 2 is allowed to stand still in the classification tank 1 or under a weak stirring or a weak aeration,
The ground consolidation powder in the suspension 2 has a fine particle diameter, that is, a powder having a low specific gravity stays upward, and a coarse particle, that is, a powder having a high specific gravity sediments downward, and has a small particle diameter. Move according to size. 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. Normally, the valve 6 is in a closed state. However, after the suspension having a distribution state having a different particle size is formed in the classification tank 1 as described above, the suspension is received by receiving information from the controller 5 and the valve 7. Open together,
At the same time, the valve 8 is closed and the lower suspension 2 in the classification tank 1 is
That is, the suspension 2 having a coarse particle size is guided to the storage tank 9.

Eventually, the liquid level 2a 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.

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 turbid 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.

The above-mentioned suspension 2 may contain one or more of water glass, alkali, a reactant and the like together with the above-mentioned ground consolidating 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 is mentioned, as the alkali, caustic soda, cement, slaked lime, etc., and as the reactant, sodium aluminate, carbonic acid or Alkaline salts such as alkali metal salts of bicarbonate can be mentioned.

FIG. 2 shows a modification of the apparatus shown in FIG. 1, in which the storage layer 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, the controller 5
First, only the valve 22 is opened and the other is closed, and the upper part of the classification tank 1 is introduced into the storage tank 18 through the conduit 20, and then the information from the controller 5 is received. With the valves 21a, 21b, and 21c opened and the others closed, the intermediate part of the classification tank 1 is introduced into the storage tank 17 through the conduit 19, and thus each part of the classification tank 1 is sequentially valved from the top. Separate into each storage tank by operation. Then, the lowermost part receives information from the controller 5 from the bottom of the classification tank 1 and opens only the valve 6 as in FIG.
Others are introduced into the storage tank 9 through the conduit 14 in a closed state to be separated, but may be separated from the side wall (not shown) as described above.

The classification tank 1 described above can be of any shape, but in particular, as shown in FIG. 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 above-mentioned 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. Of course, the suspension 2 may contain the above-mentioned deflocculant, flotation reagent and the like, as in FIG.

The suspension 2 described above is supplied to the classification tank 1 as in FIG.
Set aside in the stirrer, or stirrer 3 or air compressor 4
Is slowly operated to form a suspension in a distribution state in which the particle size gradually increases from top to bottom.

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 23 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 a 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 information from the controller 5, first, the valve 6 and the valve 28 are closed, the valve 26 is opened, and the lower suspension in the classification tank 1 is started. 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 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. Further, the storage tanks shown in FIGS. 1 to 4 are configured to communicate with the above-described water glass, alkali, a reaction agent tank loaded with a reaction agent, and the like. It can also be added.

The above-mentioned suspension according to the present invention includes ground consolidating powders such as slag, cement, calcium carbonate, gypsum, pozzolans (fly ash, silica fume, white carbon, clay, diatomaceous earth, acid clay, etc.). As described above, the cement hardens by itself, so the suspension may be classified and separated, and injected separately, but the other suspensions do not harden by themselves. Need to add reactants. 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.

In the above suspension, the slag does not solidify by itself, but the silica colloid obtained by passing water glass, especially low-molar-ratio water glass, and water glass through an ion-exchange resin to remove most alkalis. By adding a liquid or a salt exhibiting alkalinity, for example, sodium aluminate, sodium bicarbonate, sodium carbonate, an alkali, for example, caustic, lime, cement, etc., the latent hydraulic property is stimulated to harden.

Further, pozzolans do not harden by themselves, but when mixed with lime or slag in the presence of alkali, silica is eluted and gelled. These pozzolans may be used in combination with other suspensions, or these suspensions may be arbitrarily combined.

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

As the reactant, an acid, salt, glyoxal, ester such as polyvalent acetic acid ester, ethylene carbonate, organic salt, organic acid or the like which reacts with water glass, a reactant such as water glass with alkali through an ion exchange resin. Can be used.

A concrete ground pouring method for actually pouring the ground consolidation pouring solution produced according to the present invention into the ground will be described below in detail with reference to FIGS.

FIG. 6 is a block diagram of a concrete example of the ground consolidation pouring solution produced by the producing apparatus shown in FIG. 4, and the fine particle slag suspension 2 in the classification tank 1 is stored in the storage tank 9. And the coarse particle slag suspension 2b in the separation tank 23 is stored in a storage tank.
Flowed down to 30. In the storage tanks 9 and 30, an optional reactant is added from the reactant tanks 37 and 38 as needed to prepare a compounded liquid.

As an example, an alkaline agent A such as caustic alkali or slaked lime, an alkaline salt B such as sodium aluminate, or an alkali metal salt of carbonic acid or bicarbonate, is placed in the storage tank 9 from the reactive agent tank 37. Alternatively, water glass, particularly water glass C having a lower molar ratio than No. 3 water glass, is added, and the mixture is sufficiently mixed by rotating the stirrer 35, so that the gelation time is within several hours (several hours to several tens of minutes). A set suspension is obtained.

To the storage tank 30, No. 3 water glass or high molar ratio water glass D, slaked lime E, or cement F is added from the reactant tank 38, and the mixing liquid is sufficiently mixed by rotating the stirrer 36. Prepare.

An aqueous solution G of a bicarbonate or a carbonate, an alkaline salt H or an alkaline agent I are prepared in a reactant tank 39.
Further, No. 3 water glass liquid D, slaked lime E or cement F is prepared in the reactant tank 40. When suspending the slag in the classification tank 1 described above, an optional reactant may be mixed in advance.

In the injection method shown in FIG.
42 is operated to mix and mix the next compounding solution, and a combination of suspensions having different gelling times and different permeability is injected.

An example of a grout having a short gelation time Pumping liquid 41 Pumping liquid 2b + DG or any salt or acid 2b + EE or G or any salt 2b + F H, E or G or any salt In the above, sodium bicarbonate acts as a gelling accelerator.

Example of grout having a long gelation time Pumping liquid feed Pumping liquid feed 2 + A ─── 2 + B ─── 2 + C ─── 液{2 + AG or H 2 + B} 2 + C} In the above, sodium bicarbonate acts as a gel retarder.

FIG. 7 is a block diagram showing an example of application of the present invention to the double pipe double packer method, in which slag is used as a ground consolidating powder in a suspension.

First, a coarse particle suspension of slag flows down from the separation tank 23 to the storage tank 30. The suspension is then added to the suspension
After adding a cement suspension from 38 to give curability,
This suspension is sent through the pump 45 to the inner pipes of the double injection pipes 46 and 47, respectively. At this time, the injection pipes 46 and 47 are pulled up from below to change the injection stage, and the suspension is primarily injected into a rough or weak portion of the ground at each depth. In addition, if necessary, the suspension was added to water glass, an alkali agent, a silica colloid, an alkaline salt from the reaction agent tank 48,
A reactant or the like may be added and mixed.

After the above-described coarse particle suspension has been primarily injected,
Next, the fine particle suspension of the slag flowing down from the classifying tank 1 to the storage tank 9 through the valve 6 and the conduit 14 is added to the desired reactant from the reactant tank 37, and further, from the reactant tank 49 through the pump 43. A desired injection solution as a secondary injection solution is prepared by adding and mixing the reactants, and the solution is sent to the injection pipes 46 and 47 through the pump 44, and the secondary injection solution is injected into the fine soil into which the primary injection solution has not penetrated. I do.

In preparing the secondary injection solution, the storage tank 9
From the reaction agent tank 37, water glass, particularly water glass having a low molar ratio of 2.0, an alkali agent such as caustic soda, sodium aluminate,
One or more kinds of alkaline salts such as sodium carbonate and sodium bicarbonate are added and mixed together to obtain an injection solution having a desired gelation time.

In the above, when the gelation time of the injection solution is shortened, the gel time adjusting agent from the reaction agent tank 49 is joined above the injection pipes 46 and 47 and injected into the ground through the inner pipe. I do. Alternatively, the addition of the reactant tank 37 to the storage tank 9 is stopped to make only the fine particle suspension, and water glass or the like from the reactant tank 49 is added and mixed through the pumps 43 and 44 to the ground. inject.

FIG. 8 is a block diagram showing an example of application of the present invention to a multi-tube mixed injection method. Here, using a double tube rod, inject grout with a short gelation time and then inject a grout with a long gelation time, or use a double tube or a triple tube to gel from the upper discharge port. By injecting grout with short time and grout with long gelation time from the lower outlet, the rough part of the ground is filled with grout with short gelation time and grout with long gelation time in the thin part. An example applied to a method of infiltrating is shown.

As the ground consolidation powder, slag is used.
The suspension containing the coarse particle slag is an injection solution having a short gelation time, and the suspension containing the fine particle slag is an injection solution having a long gelation time.

In FIG. 8, first, a suspension of slag is prepared in the classification tank 1, and then a suspension of fine particle slag is separated in the classification tank 1, and a suspension of coarse particle slag is separated in the separation tank 23. Thereafter, the suspension of the fine particle slag flows down to the storage tank 9 and the suspension of the coarse particle slag flows down to the storage tank 30.

Further, each of these suspensions was mixed with a mixing tank 5.
After flowing down to 0 and 51, a water glass solution is added to these suspensions from the reactant tank 52 and mixed. Cement, lime, an alkaline agent, an alkaline salt or the like may be added to the suspension in the mixing tanks 50 and 51 from the reaction agent tank 52. If the No. 3 water glass is used as the above-mentioned water glass solution, since it has low alkalinity, when the addition amount is small, the gel time becomes several hours or more even when mixed with the slag,
There is no gelation during the operation in the mixing tanks 50,51. When water glass with a high molar ratio of 3 or more water glass is used, the mixture of this water glass and slag can be reduced to several seconds by adding lime and other quick-setting agents to it. It can be used as a quick setting primary injection material.

Further, an alkali agent (eg, an alkaline salt such as caustic alkali or sodium aluminate, a low-molar-ratio water glass, etc.) is added to a mixed solution of water glass having a high molar ratio of No. 3 water glass or higher and slag, thereby obtaining a slag. The potential hydraulic property of
The mixed solution gels within a few hours and develops hydraulic properties to form a high-strength compact, so that it can be used as a slow-setting secondary injection material.

In FIG. 8, a reaction tank 52 stores No. 3 water glass, a reaction tank 53 stores slaked lime suspension, and a reaction tank 54 stores sodium aluminate solution.

First, a mixed liquid of the suspension of coarse particle slag from the storage tank 30 and the No. 3 water glass from the reactant tank 52 is prepared in the mixing tank 51, and this mixed liquid and the mixed liquid from the reactant tank 53 are prepared. The slaked lime aqueous solution is operated by the pumps 57 and 58 to operate the mixing chamber 56 at the tip of the double pipe 55.
Into the ground, and primary-injected into the ground as instantaneous grout, forming a packer in the rough part of the ground or in the gap with the injection pipe.

Next, in the mixing tank 50, a mixed liquid of the suspension of the fine particle slag from the storage tank 9 and the No. 3 water glass from the reactant tank 52 is prepared. Then, the mixed liquid and the aqueous sodium aluminate solution from the reactant tank 54 are mixed and mixed, and the obtained mixed liquid is stored in a storage tank.
It is transferred to 60, and the pump 58 is operated to inject secondarily into the ground from the tip 61 of the double pipe 55 as loosened grout, so that it penetrates into the fine soil layer.

In the mixing tank 59, a suspension of fine particle slag and water glass having a lower molar ratio than No. 3 water glass may be mixed and mixed, and this may be used as a secondary injection material. In this case, in the combined liquid mixture, the latent hydraulic property of the slag is stimulated by the alkali content of the low-molar-ratio water glass and gels within a few hours, and a high-strength consolidated body can be obtained.

Further, by mixing the suspension of fine particle slag and an alkali agent (such as caustic alkali or sodium aluminate) in the mixing tank 59, the mixture gels within several hours to form a high-strength compact. Can be obtained.

It should be noted that, even if a quick-setting admixture is added to a mixture of low-molar-ratio water glass and slag, or a mixture of alkali and slag, it is difficult to obtain a flash-set primary injection material having a gelation time of several seconds. (3) When a quick-setting admixture is mixed with a mixture of No. 3 water glass and slag, a quick-setting primary injection material having a gel time of several seconds can be easily obtained.

Further, fine cement, fine hydrated lime or bicarbonate is mixed with the coarse particle slag suspension in the mixing tank 51 through the reactant tank 53 through the reactant tank 52.
No. water glass or water glass with a higher molar ratio than it is prepared, and these are merged in the mixing chamber 56 at the tip of the injection pipe 55 by the operation of the pumps 57 and 58, respectively, to form a flash grout and to perform the primary injection. You can also. Although the above-described various mixing tanks are not shown, a line mixer may be used.

[0065]

The function of the powder used in the present invention will be described with reference to a representative slag. The same applies to the case where this slag is obtained by mixing an appropriate amount of cement.

When the alkali of water glass, the alkali of cement or the like acts on the slag, the slag exerts its inherent hydraulic potential. This is because the slag is hardened by the stimulating action of the alkali. Further, the above-mentioned action is greatly increased by making the slag finer. In this case, since the slag is finely divided, the suspension itself maintains a low viscosity. Therefore, the suspension is solidified after a long time and has excellent permeability.

The present invention utilizes the principle that the gravitational force and the fluid resistance received in the fluid by the difference in the slag particle size in the suspension are different, and the particles having a low specific gravity are suspended in the rising water flow of the slag suspension. The particles are allowed to settle. further,
The present invention utilizes classification by particle size as well as separation by specific gravity of particles. That is, according to the present invention, even light particles having a large particle size settle, and even heavy particles have fine particles suspended, so that a slag powder having a wide particle size range can be selected.

In the present invention, when the suspension exhibits a deflocculation phenomenon, a deflocculant can be added to the suspension to generate a colloid solution, thereby improving the separation ability. Also,
The present invention can also enhance the separation ability by the principle of flotation.

[0069]

The present invention will be described in more detail with reference to the following examples. Of course, the invention is not limited to slag only.

1. Materials Used (1) Slag Granulated slag having the component composition shown in Table 1 and having the particle size distribution shown in FIG. 9A was used.

[0071]

[Table 1]

(2) Water Glass Two kinds of water glasses having the component compositions shown in Table 2 and having different molar ratios were used.

[0073]

[Table 2]

(3) Cement Portland cement having the component composition shown in Table 3 and having the particle size distribution shown in FIG. 10A was used.

[0074]

[Table 3]

(4) Slaked lime Industrial slaked lime having a particle size distribution shown in FIG. 11A was used.

(5) Sodium aluminate solution A sodium aluminate solution having the following composition was used. Na ₂ O: 22.47%, Al ₂ O ₃ : 1.59%, Molar ratio: 23.25 Specific gravity: 1.33

(6) Fly ash As the pozzolans, fly ash comprising 0.6% of ignition loss and 49.8% of SiO ₂ and having a particle size distribution shown in FIG. 12A was used.

2. Separation Test A separation test of the raw powder was performed using a classification tank 1 of the type shown in FIG. 4 (however, in this example, the diameters of the classification tank 1 and the separation tank 23 were the same).

(1) Slag 150 kg of the slag indicated by the solid line a in FIG. 9 is put into 250 liters of water in the classification tank 1, and the mixture is vigorously stirred for 5 to 10 minutes to sufficiently disperse and suspend, and is allowed to stand for about 5 minutes. Thereafter, the valve 26 was gently opened, and the lower suspension was gently transferred into the separation tank 23. The amount of slag in the classification tank 1 is 60 kg / water 120 l, and the separation tank 23
The amount of slag in the suspension is 80 kg / 120 l of water, and the particle size distribution of the slag in each suspension is as shown by the dotted line in FIG. 9 (b: classification tank 1, c: separation tank 23). We were able to perform almost satisfactory sorting.

(2) Cement, slaked lime and fly ash Portland cement indicated by a solid line a in FIG. 10, industrial slaked lime indicated by a solid line a in FIG. 11, and fly ash indicated by a solid line a in FIG. Was done.

The particle size distributions in the coarse particle suspension and the fine particle suspension are shown by the dotted lines (b: classification tank 1,
c: The result as shown in the separation tank 23) was obtained.

The powder other than the slag could be separated into a coarse particle suspension and a fine particle suspension to an almost satisfactory degree.

3. Injection test (1) An injection test was performed on the ground where the coarse-grained soil layer and the fine-grained soil layer were alternated using the apparatus shown in FIG. A fine particle slag suspension (storage tank 9) and a coarse particle slag suspension (storage tank 30) separated in the above-mentioned separation test are prepared, and a suspension composed of cement and slaked lime is placed in the reaction agent tank 52. A sodium aluminate solution was prepared in the reaction tank 54, and a water glass (molar ratio 2.96) No. 1 in Table 2 was prepared in the reaction tank 53.

Next, the coarse particle slag suspension 2b and the suspension in the reactant tank 52 are mixed in the mixing tank 51, and this mixed liquid is pumped.
The liquid is sent to the double pipe 55 by the operation of 58, and the water glass is sent to the double pipe 55 by the operation of the pump 57 from the reactant tank 53,
These are mixed in the tip mixing chamber 56 to form a quick-setting grout,
From the tip 61, it was injected into the ground consisting of alternating layers of coarse sand layer and fine sand layer as the primary injection material.

Then, subsequently, the fine particle slag suspension 2
And the sodium aluminate solution in the reactant tank 54 were mixed in a mixing tank 59 to form a loose grout.
It was injected into the ground through 61 as a secondary injection material. Here, a water glass (molar ratio: 2.04) liquid of No. 2 in Table 2 was used instead of the sodium aluminate liquid in the reactant tank 54, and reacted with the fine particle slag suspension 2 as a secondary injection material. A mixed solution of low-molar-ratio water glass (No. 2 in Table 2) in the agent tank 54 can be injected as a loose grout.

Further, caustic soda was prepared as an alkali agent in the reactant tank 54, and No. 1 water glass (molar ratio 2.96) in Table 1 was passed through the reactant tank 52 to suspend fine particle slag in the mixing tank 50. It is also possible to mix with the liquid 2, mix this mixed liquid with the alkali agent from the reaction agent tank 54 in the mixing tank 59, and inject the mixture as a loose grout.

As a result of the excavation investigation, a homogeneous compact was formed in both the coarse sand layer and the fine sand layer, centering on the injection pipe. For comparison, the suspension of the raw slag was used as it was instead of the separated slag suspension. As a result, although the suspension permeated the coarse sand layer, a compact was formed irregularly in the fine sand layer, and uniform compaction could not be obtained. Also, for comparison, when only the above-mentioned secondary injection material was injected, the consolidated body was inferior to the above-described one, and in particular, the consolidability of the coarse sand layer was inferior. This indicates that it is extremely effective to separately and separately use the coarse particle suspension and the fine particle suspension in the present invention.

In particular, the fine particle suspension obtained according to the present invention exhibits a permeability almost equivalent to that of a conventional solution-type grout, and can obtain a high-strength compact unique to suspension grout. Excellent in reactivity. On the other hand, the reactivity of the coarse particle suspension is small, but by adding an alkali such as cement or slaked lime to the suspension, the reactivity can be improved to obtain a high-strength consolidated body.

4. Injection Test (2) Various injection tests were performed using the laboratory injection apparatus of FIG. That is, an acrylic mold 107 was filled with soil 108 having different particle sizes, and various injection materials were injected therein. This injection was carried out by filling the injection material 106 into the water tank 105 and operating the compressor 101 to feed the injection material 106 to the soil 108 while stirring it with the stirrer 104 .
In Figure 13, 102, 103 a pressure gauge, 109, 110 wire mesh, 111
Is a measuring cylinder. The test was performed by comparative observation. Table 4 shows the results.

[0090]

[Table 4]

From Table 4, it can be seen that, as shown in Example No. 7, the primary injection liquid used was coarse particles separated by the classification and separation apparatus of the present invention, and the secondary injection liquid was separated fine particles. It can be seen that the use of the compound of the formula (1) produces the most excellent effect.

[0092]

As described above, according to the present invention, a suspension containing ground consolidation powder such as slag can be easily separated into a coarse particle suspension and a fine particle suspension. Of these, the coarse particle suspension is mainly mixed as a high-strength suspended grout with a relatively short gelation time, or is added as cement or lime and injected as a high-strength primary injection material. It requires a long gelling time and exhibits a permeability almost suitable for a solution type grout, and is injected as a secondary injection material as a high-strength suspension type grout to sufficiently exhibit the excellent effects of each.

In the embodiment, the case where the powder raw material is classified and separated is shown. However, if the finely divided powder is classified and separated, it is needless to say that the permeability can be further improved at the level of fine particles. is there. In this case, it is possible to solve the problem that the more the particles are made finer, the more the cost is increased.

For example, slag or cement, or a mixture of cement and slag, having an average particle size of 10 μm
Hereinafter, if the particles having a Blaine specific surface area of 7000 cm ² / g or more are classified and separated according to the present invention, an ultrafine particle suspension having an average particle diameter of 5 μ or less and a Blaine specific surface area of 10,000 cm ² / g or more and a coarser particle suspension It can be easily separated into a fine particle suspension.

Further, if necessary, the average particle size may be 1 to
3μ or less, Blaine specific surface area 15000cm ² /
g or more, and can be easily separated into a suspension of ultra-fine particles and a coarser suspension.

According to a permeation test, those having a specific surface area of 7000 cm ² / g cannot penetrate into Toyoura standard sand.
However, at 8000-10000 cm ² / g, it can penetrate according to the relative density of Toyoura standard sand. However, if the soil becomes finer than standard sand, the specific surface area of the brane is 10,000
cm ² / g is required to be or more, further, if the Blaine specific surface area of 15000cm ² / g~20000cm ² / g or more, the, the permeability is not substantially the same as the solution-type injection material.

However, in practice, it is almost impossible economically and technically to pulverize the particles to such a small particle size. However, if the present invention is used, the Blaine specific surface area is 7000 to 10000 cm ² / g.
Separation of a suspension of ² / g or more is possible.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a specific example of one type of manufacturing apparatus used in the method of the present invention.

FIG. 2 is a schematic view showing another specific example of one type of manufacturing apparatus used in the method of the present invention.

FIG. 3 is a schematic view showing a specific example of another type of manufacturing apparatus used in the method of the present invention.

FIG. 4 is a schematic view showing another specific example of the other type of manufacturing apparatus used in the method of 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 showing one specific injection example according to the method of the present invention.

FIG. 7 is a schematic view showing another injection example according to the method of the present invention.

FIG. 8 is a schematic view showing still another injection example according to the method of the present invention.

FIG. 9 is a graph showing the relationship between the particle size of slag and the equalization rate.

FIG. 10 is a graph showing a relationship between a particle size of Portland cement and an equal passage rate.

FIG. 11 is a graph showing a relationship between a particle size of slaked lime and an equal passage rate.

FIG. 12 is a graph showing the relationship between the particle size of fly ash and the equalized passage rate.

FIG. 13 is a schematic diagram of a laboratory injection test device.

[Explanation of symbols]

 1 Classification tank 2 Suspension 2a Suspension 2b Suspension 3 Stirrer 4 Air compressor 5 Controller 6 Valve 7 Valve 8 Valve 9 Storage tank 11 Storage tank 12 Pipe 13 Pipe 14 Pipe 17 Storage tank 18 Storage tank 19 Pipe 20 Pipe 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 55 injection pipe 56 tip mixing chamber 61 tip

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification code FI C09K 17/08 C09K 17/08 P 17/10 17/10 P 17/12 17/12 C04B 111: 70 C09K 103: 00 (58 ) Surveyed field (Int.Cl. ⁷ , DB name) E02D 3/12 C09K 17/02 C04B 22/08 C04B 28/00 C09K 17/06 C09K 17/08 C09K 17/10 C09K 17/12

Claims (10)

(57) [Claims] 1. A suspension containing ground consolidation powders having different particle diameters is filled in a classification tank to form a distribution state in which the particle diameter gradually increases from the upper side to the lower side. The suspensions having different particle size distributions are separated from the tank, and a plurality of ground consolidation injection solutions containing the powders having different particle sizes are manufactured, and a coarse-grained soil layer and large voids in the ground are produced. It is characterized by injecting an injection liquid containing a powder having a coarse particle diameter into the soft layer having the same and an injection liquid containing a powder having a fine particle diameter into the fine-grained soil layer of the ground, whereby the entire ground can be formed. A ground injection method that not only rationally solidifies but also uses the powder without waste. 2. The soil injection method according to claim 1, wherein the suspensions having different particle size distributions are separated by sequentially taking them out from the bottom of the classification tank. 3. The soil injection method according to claim 1, wherein the suspensions having different particle size distributions are separated by sequentially taking them out from the top through a classification tank side wall. 4. The method according to claim 3, wherein the lowermost suspension in the classification tank is separated from the bottom of the classification tank. 5. The method of claim 1, wherein the ground consolidation powder is one or more selected from the group consisting of slag, cement, calcium carbonate, lime, gypsum, and pozzolans. 6. The method according to claim 1, further comprising:
2. The method for injecting ground into a ground according to claim 1, wherein the method includes at least one of an alkali and a reactant. 7. The method of claim 6, wherein the suspension is a suspension in a classification tank. 8. The soil injection method according to claim 6, wherein the suspension is an injection liquid for solidifying the ground separated from the classification tank. 9. The method according to claim 1, wherein the classification tank is a stirrer or a stirrer.
2. The ground injection method according to claim 1, further comprising an air compressor.
Construction method. 10. The classification tank according to claim 1, wherein the classification tank is substantially inverted.
The method of claim 1 having a conical shape.