KR800001254B1 - Method of consolidating poor quality soils - Google Patents

Abstract

a mixture of water and a gelling agent, B: a water glass aqueous solution containing a gelling agent. The steps comprises; first, A and B liquid are injected into the soil simultaneously, second, during the injection, the joining operation of a liquid is syspended and B liquid is injected into the soil.

Description

How to Freeze Soft Ground

The present invention relates to a method for solidifying soft ground, in particular a novel method for improving the ground with a solid index of solidified soft or leaky ground.

In the present specification, the term “soft ground” refers to soft ground or leaky ground which can be seen at the time of building foundation construction or underpass or underground excavation construction. In addition, the "solid freeze" means to improve the solid and exponential ground by injecting various freezes into the soft ground to solidify the ground.

In general, the soft ground is formed of heterogeneous ground in which granulated soil layers (including voids) and fine-grain soil layers are formed into arc layers. Therefore, such a soft ground needs to be solidified by injecting a high settlement into it in various constructions.

Homogeneously solidifying soft ground in the present invention means to improve not only the pressure resistance of the ground but also the index characteristics by solidifying both layers of the granulated soil layer and the fine-grained soil layer. In other words, integrating only one of the two layers forming the soft ground is not considered to be homogeneous in the present invention.

Because integrating only one layer can not increase the pressure resistance and expect the exponential capacity of the ground.

Previously known soft ground freezing methods included:

(1) Two-liquid water glass industry

In this conventional method, a suspension containing an aqueous solution of an inorganic crosslinking agent or cement (A solution) and a water glass aqueous solution (B solution) is used as a high binder.

These solidifying agents or liquid A or liquid B are combined together through a Y-shaped pipe roll, and the combined liquid (hereinafter referred to as AB liquid) is injected into the ground to be solidified. This process is simple in operation and has good freezing effect, but actually has the following drawbacks.

(A) Solution A and Solution B react and solidify as they are mixed. However, if they remain as unreacted substances in the ground, they cause problems such as groundwater contamination. Particularly, if B liquid remains as unreacted material in the soil, it is leaked into the groundwater in the ground and is extended to serious pollution. Therefore, in order to solve such a difficulty, that is, in order not to leave unreacted substances in the ground, it is necessary to completely combine the A and B liquids in a certain ratio.

However, this is a very difficult problem in practice. In particular, when the injection pressure of the nutrient solution is strong or when the injection amount is a small amount, the injection ratio of the A liquid to the B liquid is largely varied, and even only one of the two liquids is transported. Therefore, this conventional method is that the unreacted material remains in the ground, which will soon deviate into the groundwater causing pollution problems.

(B) A liquid and B liquid are exchanged rapidly at the time of merging. When liquid A contains cement, liquid A containing cement is a suspension, so liquid AB and liquid B obtained by combining liquid B are also one suspension. As a result, the AB liquid is poorly permeable, and as a result, it cannot penetrate more than the granulated soil layer.

As described above, it is true that the fine grains hardly penetrate into the fine-grained soil layer by this conventional method, and as a result, the ground treated by this method is inhomogeneous.

(2) The conventional method, which is a water glass injection method using an organic coagulating solution, is a method of using a solution water glass using an aldehyde compound or an ester as a coagulant, and the time for solidification can be considerably long. Therefore, the process of merging liquids is unnecessary in this process. Furthermore, the water glass and the high binder can be reliably combined in advance and injected by a so-called "one shot" method. In addition, in this case, since the solution-type chemical liquid (주입 型 藥液), even fine-grained soil layer can be injected homogeneously.

However, this conventional method also has a defect. That is, since the high binder is an aqueous solution, the high binder naturally has excellent permeability. Because of this property, the high settlement deviates out of the injection range in the void or granulated soil layer. For this reason, it becomes difficult to solidify large voids and granulated soil layers, and therefore, even in this conventional method, it is difficult to form homogeneous solidified ground.

In view of the above-described deficiencies of the conventional method, the present invention is to provide a novel method of freezing in which the high settlement is deviated from the groundwater and causes pollution such as groundwater contamination in solidifying the soft ground.

Another object of the present invention is to provide a method for homogeneously solidifying both layers by injecting a binder into both layers of the coarse soil layer and the fine-grained soil layer.

Another object of the present invention is to provide a method for improving a soft ground into a ground having high internal pressure by solidification.

In addition, it is included as one of the objects of the present invention to support the method of improving the soft ground to exponential ground by the solidification.

It is a special object of the present invention to provide a method of precisely solidifying a desired part of the ground by injecting and penetrating a high settlement into a desired direction in the ground, that is, in a desired direction.

The above and other objects are achieved by using a high binder in a mixture obtained by mixing the water and the high binder according to the present invention by mixing a water glass aqueous solution containing a crosslinking component, and incorporating these high binders into the ground. The binder is selected from the groupings consisting of esters, aldehydes, inorganic acids, organic acids, inorganic salts, cements and hydraulic cements.

Such features of the present invention are described in more detail with reference to the following examples.

First, a liquid consisting of a mixture of water and a high binder (hereinafter referred to as A solution) and a water glass aqueous solution containing a high binder (hereinafter referred to as B solution) are prepared, respectively. As apparent from the foregoing, solution A may be an aqueous solution, but it may be replaced with a cement suspension or a simeth suspension containing clay such as bentite or sand. On the other hand, the water glass aqueous solution, namely B liquid, has a relatively long solidification time, so that it does not gel before being injected into the ground.

Most of the commercially available water glass has a molar ratio in the range of 1.5 to 5.0. Meanwhile, examples of the above-mentioned solidification reagents are as follows.

Esters:

Fatty acid esters of monohydric alcohols such as ethyl acetate, methyl acetate, butyl acetate and amyl acetate,

Fatty acid esters of polyhydric alcohols, such as ethylglycol diacetate, glycerin triacetate, and diesters of succinic acid (complete esterification):

Intramolecular esters, such as (gamma) butyrolactone and (epsilon) -captoractam (cyclic ester: lectone).

Ethylene glycol mono-formate, ethylene glycol alcohol, mono-acetate,

Ethylene glycol mono-propionate, glycerin mono-formate,

된 비닐아세테이트(저급중합)등의 폴리하이드릭 알코올의 부분적으로 에스테르화된 에스테르디 아세톡시-에틸렌

등의 불포화지방산 에스테르Glycerin mono-acetate, glycerin mono-propionate, glycerin di-formate, glycerin di-acetate, sorbitol mono-formate, sorbitol mono-acetate, glucose mono-acetate and partially saponification

Partially esterified esters of diacetoxy-ethylene of polyhydric alcohols such as vinyl acetate (lower polymerization)

Unsaturated fatty acid esters

Carbonates such as cyclic carbonates such as methylene carbonate, propylene carbonate and glycerin carbonate.

Aldehydes:

Aldehydes such as glyoxane, succinic dialdehyde, marondialdehyde, succinic aldehyde, glutaraldehyde and flutal dialdehyde.

Acids:

Inorganic acids such as sulfolic acid, hydrochloric acid and phosphoric acid;

Organic acids such as matonic acid, succinic acid, maleic acid and tartaric acid;

Inorganic salts:

Chlorides or hydrochlorides such as calcium chloride, sodium chloride, potassium chloride, ammonium chloride, zinc chloride and aluminum chloride;

Sulfates such as sodium sulfate,

Aluminates such as sodium aluminate and potassium aluminate.

Chlorates such as sodium chlorate, potassium chlorate, sodium perchlorate, and potassium perchlorate.

Carbonates such as ammonium carbonate, sodium bicarbonate, potassium bicarbonate, and ammonium bicarbonate.

Bisulfates such as sodium bisulfate, potassium bisulfate and ammonium bisulfate.

Bisulfates such as sodium bisulfate, potassium bisulfate and ammonium bisulfate.

Fluorosilicates such as sodium silica fluoride and potassium silica fluoride.

Borate salts, such as sodium borate, caloryrate, and ammonium borate.

Hydrogen phosphates such as sodium hydrogen phosphate, potassium hydrogen phosphate and ammonium hydrogen phosphate.

Pyrosulfates such as sodium pyrosulfate, potassium pyrosulfate and ammonium pyrosulfate.

Pyrophosphates such as sodium pyrophosphate, potassium pyrophosphate and ammonium pyrophosphate.

Biclomates, such as sodium bichloromate, sodium bichloromate, and ammonium bichloromate.

Permanganate, such as potassium permanganate and sodium permanganate.

Iron chlorides such as Ca, Al, Mg or lime, gypsum, alumina, iron oxides, magnesium oxide, slugs, calcium silicates and clays (those that produce silicates in combination with silicic acid).

Organic Salts:

Sodium acetate, sodium succinate, potassium polymate, sodium polymate, etc.

Cement

Portland Cement, Portland Blast Furnace Cement, Slug Cement, Colloidal Cement etc.

Hydroponic Components of Cement

This means the supernatant of the cement suspension, which is obtained as the supernatant of the upper layer of the suspension by leaving the cement suspension obtained by mixing water and cement with stirring for several minutes. This can also be obtained by mixing water glass, water and cement with the equations described above. In this case, the supernatant obtained is used as the B solution.

A liquid and B liquid are combined by using a Y-shaped pipe, for example, and injected into the soft ground (or loose ground) through an injection pipe.

The liquid obtained by joining this liquid A and liquid B (hereinafter referred to as AB liquid) is solidified within a time earlier than the solidification time of liquid B due to the action of the solidifying agent contained in liquid A. This freezing time can be arbitrarily adjusted by selecting suitably the compounding ratio with respect to the quantity of liquid B of the amount of the freezing agent contained in liquid A.

In the method of the present invention, even if the supply ratio (or transportation cost) of the liquid A to the liquid B is changed or changed, the solidification of the liquid AB first hardens the granulated soil layer first. Next, the liquid B penetrates into the fine-grained soil layer and hardens it. As a result, both layers of the fine-grained soil layer and the coarse-grained soil layer are solidified, thereby forming a firm solidified ground homogeneously integrated in strength and soil quality. Therefore, when the method of the present invention is carried out, there is no closure as in the previous method, i.e., only the granulated soil layer is solidified and the fine grained soil layer is not solidified or only the fine grained soil layer is solidified and the granulated soil layer remains intact. That is, according to the method according to the present invention, the AB liquid and the B liquid play a solid role of the granulated soil layer and the fine-grained soil layer, respectively, so that the present method is called a "composite grout method". Because solution B itself can be solidified itself, if solution (A) is a cement suspension, solution A can also be solidified itself), and solution B is solidified without any help. Therefore, liquid B never deviates from the injection region or the injection range. In other words, liquid B never enters ground water, for example. This means that there is no fear that the method according to the present invention will cause pollution problems such as contamination.

And such characteristic effects and advantages of the method of the present invention can be obtained and made without controlling the inflow of the liquid A and liquid B.

Now, another embodiment of the method according to the present invention will be described. This is to inject a predetermined amount of AB liquid on the ground, and then to inject A liquid only B liquid.

In this process, since the AB liquid first injected is solidified within a relatively short time as described above, the AB liquid first penetrates into the large voids, the interface of the strata or the granulated soil layer (collectively referred to as granulated soil layer hereinafter). Only to be entrusted soon. Then, the supply of the liquid A is stopped and the injection of the liquid B is continued. Since the AB liquid was injected into the granulated soil layer described above, B liquid (which is excellent in permeability because it is an aqueous solution and can control its solidification time for a relatively long time) gradually penetrates into the fine-grained soil layer and then interlocks.

As such, the high settlement continues to be distributed from the granulated soil layer to the fine-grained soil layer without interruption, thereby improving loose soil soil more quickly and easily homogeneously solidifying to solid ground.

In the present method, it is necessary to continuously inject AB liquid and B liquid in the above-described order. In this continuous operation, since the B liquid is injected before the AB liquid is completely solidified in the coarse soil layer, the B liquid penetrates the AB liquid layer and penetrates into the fine grain soil layer. Therefore, B liquid easily penetrates into the fine grain layer. In addition, the solidification time of liquid B can be adjusted to a relatively long time, thereby enabling widespread penetration of liquid B into the fine-grained soil layer.

In the present invention, when the solution A is a cement suspension, a surface aid may be used to improve the diffusion of the high binder contained in the solution B.

As a means for joining the liquid A and liquid B together, a double injector pipe or two injections can be used in parallel instead of the Y-type pipe described above. In this case, the double pipe or two pipes are inserted into the ground to be solidified, and the liquid A and liquid B are discharged immediately before or immediately after being discharged from the outlet of each injection pipe or, if necessary, are discharged and joined together.

In the present invention, the method of injecting a high settlement into the ground can take various aspects. For example, a very simple load injection method can be used, but this method has the following drawbacks. In other words, according to this method, an ultimate is formed between the grounding rod and the ground, so that the high binder injected under pressure ejects the ground along the void, and consequently penetrates the high binder into the fine soil layer. It becomes difficult to let them. In order to solve this difficulty, it is necessary to shorten the gelation time of the high resolution, and this shortening the gelation time is shorter the time of freezing due to the shorter freezing time, so that it becomes difficult to penetrate into the fine grain soft ground. You face difficulties. The difficulties associated with such a rod injection method are not only completely solved by applying the method according to the present invention to this method, but also the advantages of the rod injection method, that is, the simplicity of operation, are survived by the application of the present invention. Specifically, by injecting AB liquid, which is a combination of liquid A and liquid B, the above-mentioned voids and other large voids in the ground are filled with AB liquid binder, and the AB liquid solidification time is short. will be. After that, the injection of A solution is suspended and only B solution is injected. In this case, the above-mentioned voids are already filled and solidified by the AB liquid, so that the B liquid cannot deviate to the void or the ground surface. That is, the liquid B is completely penetrated into the fine grain layer. Now, when the required amount of B liquid is injected, the drilling rod is pulled upward and the above-mentioned injection operation is repeated at a suitable height. In this way, according to the method combining the present invention with the conventional rod injection method, the desired injection can be easily performed.

As described above, one of the novel features of the present invention is that the grouting of the liquid obtained by joining the A liquid and the B liquid is delicately correlated with the grouting of the B liquid. For this reason, the present invention can achieve a great effect on the solidification of the ground in a relatively simple way in terms of work.

Such a method according to the present invention can be modified as appropriate depending on the state of the stake ground to be solidified. For example, when the method of the present invention is applied to a water zone, the above-described method of the present invention may be repeated while watching the water situation. In some cases, it is possible to first inject A liquid or B liquid alone, and then to inject A liquid and B liquid. In addition, the following modifications are possible. That is, a water glass aqueous solution (hereinafter referred to as B 'liquid) that does not contain the above-mentioned A liquid and a binder can be used as a high binder. These two liquids, A and B 'liquid, are combined and injected into the ground together (instead, A liquid alone may be injected and then the coating liquid may be combined). At the time of injection, B liquid is replaced with B 'liquid, and at the same time, supply of A liquid is stopped and only B liquid is injected alone. This method is most appropriately applied to the ground to accommodate large settlements. In this case, since the transport volume of the injection pump is naturally large, the combination ratio of the liquid A to the liquid B can be maintained relatively accurately. Therefore, the liquid B never flows into the groundwater as an unreacted substance. In other words, it can be seen that the method according to the present invention does not have any pollution problem.

In the execution of the method described above, the step of changing the water glass aqueous solution (liquid B) containing no work compatibilizer for injecting the liquid into the ground into the water glass aqueous solution (B ′ liquid) containing the refining agent, and the aqueous solution and A series of operations, such as stopping the confluence of the liquid (liquid A) obtained by mixing water and a high binder, can be repeatedly performed.

The water glass aqueous solution and the refining agent are mixed in a mixer to prepare a B liquid, and the water can be penetrated into the ground by transporting it at a ratio that is accurately combined with a pump. However, the composition of the liquid B can be achieved by transporting the water glass aqueous solution and the compatibilizer to the Y-type pipe by separate transport systems, respectively.

As is apparent from the above. A feature of the present invention is that the combined liquid and liquid B, in which the liquid A and liquid B are combined, are continuously injected into the ground to be solidified. If the injection of B solution is carried out after a considerable period of time after injection of AB solution, it will take time to start the construction again, and the B solution will be ground before the B solution is injected before the B solution infiltration because the AB solution is rapidly solidified. It is hampered by the cultivation of grout. However, in the present invention, since the AB liquid and the B liquid are continuously injected into the ground, that is, the B liquid is injected immediately after the AB liquid is injected, the grout of the B liquid is completely solidified in the grout of the AB liquid. You can penetrate the grout of AB fluid before.

Therefore, injection of B liquid does not interfere at all by injection of AB liquid.

Furthermore, as a modification of the method according to the present invention, a jet of a liquid B is applied to the ground to be solidified so that the ground is cut or relaxed, and then a high binder is seized at the treatment site. There is a method, which will be described in more detail.

First, drill a hole in the soft ground or loose ground, and insert the double pipe structure injection pipe consisting of the outer pipe and the inner pipe inserted therein into the hole drilled into the ground. The outer pipe of the double pipe has an open end, and the diameter is 90 mm, for example, and pipes of various diameters may be used in some cases. On the other hand, the inner pipe to be inserted therein forms a closed end, and a jet nozzle, that is, a nozzle, is provided on the closed end portion wall. The diameter of the inner pipe is, for example, 40 mm, but can be arbitrarily selected within a range smaller than the diameter of the outer pipe. Now, the inner pipe is inserted into the outer pipe, and the lower end provided with the jet nozzle of the inner pipe is positioned to turn at the lower end of the outer pipe.

Through the inner pipe, the liquid B is ejected at a pressure of several tens kg / cm 2, preferably 100-500 kg / cm 2, thereby cutting or relaxing the ground. After doing so, A liquid is injected at a pressure of about 10 kg / cm 2 to the portion treated by the ejection of B liquid. In the case of injection of this liquid A, the same high pressure as in the case of liquid B cannot be applied. The reason for this is that when liquid A is a cement suspension, jets under too high a pressure cause abrasion or blockage of the nozzle of the inner pipe.

A and B injected in this way are joined in the ground and solidified therein. Then, while rotating the double pipe, slowly moving upwards, cutting the ground and relaxing as described above, and continuously injecting and joining the liquid. Thus, cutting parts and loosening parts of the ground are solidified to form columnar solid bodies. When the double pipe is moved upward without rotating, a film-like solidified-side solidified membrane is formed. The direction of penetration is determined by the jets, which form a film-like solidified body.

As described above, in the jet flow system under high pressure, no pollution is caused regardless of the compounding ratio of the high binder, and not only the granulated soil layer but also the fine grained soil layer are solidified to improve the soft ground into a solidified solidified soil of homogeneous strength. In this method, in particular, liquid B is used to cut or relax the ground, thereby significantly improving the penetration of the high binder. Furthermore, since the direction of cutting and loosening of the ground can be arbitrarily selected, it is possible to set the direction of penetration and removal of the high binder as desired (when liquid A is a cement suspension, most of the liquid A stays in the granulated soil layer. No longer deviates, there joins the B amount and solidifies within a short time).

As is apparent from the above, according to the high pressure jet flow method, the solidifying agent (grout) using the confluence obtained by substantially combining the liquids A and B causes solidification of the granulated soil layer (which increases the ground strength). On the other hand, the solidified body (grout) using B liquid substantially serves to solidify the fine-grained soil layer, thereby completely preventing the water in the ground. As a result, both the coarse soil layer and the fine layer of the fine-grained soil layer are uniformly solidified and can be completely psoriasis into a ground having strength, index, and waterproofing.

To clarify these features and advantages of the present invention, several examples are given below.

Example 1

(1) Liquid A and liquid B were prepared at the compounding ratios shown in Tables 1-A, 1-B, and 1-C, respectively.

Each of these solutions A and B was combined to measure the gelation time, and the results are shown in the following tables.

Table 1-A

TABLE 1-B

Table 1-C

In Tables 1-A, 1-B, and 1-C, it can be seen that the solidification (gelling) time of the AB liquid obtained by combining the liquid A and the liquid B is much shorter than that of the liquid B itself. .

(2) The test work was carried out by applying the method of the present invention to a river bed layer containing groundwater.

The liquid A and liquid B of the preparation were each received at the same flow rate (15 L / min) by a separate pump and joined using a Y-shaped tube and injected through an injection tube. The site was a gravel layer with groundwater, and the penetration test result was the penetration coefficient K = 6.2 × 10 ^-2 cm / sec before injection.The penetration coefficient after injection of AB solution, which combines A and B solutions, is K = 2.5 × 10. It was found to be ^-5 cm / sec, which proves that the crime prevention gravel layer of the present invention was improved with sufficient impermeable soil.

After injection, the combined AB liquid of liquid A and liquid B was solidified in the excavated soil layer, and the liquid B was infiltrated and fixed in the fine-grained soil layer. No trace of deviation of liquid B was seen.

Example 2

The method according to the present invention was applied to an excavation site in which the fine sand layer and the irradiated layer formed an arc layer in Tokyo, Japan.

A and B liquids of the above preparation were transported at separate flow rates (10 L / min each) by a separate pump, and the Y magnetic pipes were joined together and injected through the injection pipe. After injecting A and B liquids at 20 L / min, the injection of A liquid was stopped and only B liquid was injected at 3000 L at 10 L / min.

Excavation test after injection, that is, cement and bentite were solidified around the interface of the ground and the irradiated layer, and where the cement and bentite of the irradiated layer were not contained. It turned out that the trace of deviation of B amount was not seen.

In the field permeation test, the water permeability coefficient before injection was K = 2.8 × 10 ⁻² cm / sec in the irradiation layer and K = 4.8 × 10 ⁻³ cm / sec in the fine fiber layer. K = 1.3x10 <^-6> cm / sec was shown by ^-6 cm / sec and a fine yarn layer.

In the standard penetration test, what was N = 5-10 before injection showed N = 18-26 after injection, and the excellent injection effect of the method by the invention by this invention was confirmed.

Example 3

The injection test was carried out by applying the method of the present invention to a corrosive soil layer having large voids.

The formulation of the high drug solution was as follows.

In order to transport A liquid and B 'liquid into individual pumps, they are prepared to be injected into the Y tube and injected into the injection tube. First, 1000 liters are injected into the liquid A only 15 l per minute, and then B' liquid is flown at a flow rate of 15 l per minute. A total of 1000 L of A and B 'liquids were injected by joining the transport of the liquid A. Next, only the liquid B 'was added as ethylene glycol diacetate to stop the injection of the liquid A as the liquid B, and only the liquid B was injected at 2000 L at 15 L per minute.

The results of the field permeation test indicate that K = 3.8 × 10 ⁻¹ cm / sec before injection, and K = 6.9 × 10 ⁻⁶ cm / sec after injection. As a result of the excavation test, in the large pores (coarse soil) in the corrosive soil layer, cement and bentite solidification (solidification of A and B ′ confluence) were observed, and in other parts (fine soil layer), solution glass grout (B liquid) was found. It turned out to be completely noble.

Example 4

The amount of Portland cement is added to the aqueous solution of No. 3 water glass, and the resultant mixture is stirred and the solidification time is measured and is shown in Table 2 below.

[Table 2]

50 g of Portland cement is added to 100 cc of water and mixed to form a mixed solution. 50 cc of this mixed solution was used as the A solution, while 50 cc of the mixed solution obtained by mixing 25 cc No. 3 water glass, 75 cc of water, and 1 g of cement was used as the B solution. The A solution and the A solution B, which were thus combined, were solidified in 1 minute and 10 seconds (the freezing time of B liquid was 60 minutes—Experiment 2).

The liquid A and liquid B were injected into the gravel and sand layers of Tokyo, Japan. First, A and B were 15 L / min, respectively, through the Y-tube, and the confluence was injected into the ground. After the injection of 5000 L, the transport of A was stopped, and only B was injected. In the excavation test, it was found that most of the water glass in the cement volume was substantially filled in the gravel layer, and that a small amount of water glass high binder in the cement volume was filled in the sand layer, and that the injected material did not deviate, and the ground into which the high settlement was injected. Was enclosed in a complete monolith.

Example 5

50 g of Portland cement was added to 100 cc of water to make 50 cc of the mixture A liquid.

A mixture of 25cc water glass 25cc, 75cc water and 2g cement was stirred and left to stand for 3 minutes. 50 cc of the rising layer of the mixture thus treated was used as the B liquid. These solutions A and B were mixed, and as a result, the mixed solution solidified in 50 seconds. (Experiment 1).

50 g of the Portland cement was mixed with 100 cc of water to obtain 50 cc of the mixture as A solution. Meanwhile, the mixture obtained by mixing 50 g of Portland cement with 100 cc of water was stirred for 2 minutes and then left for 3 minutes. 50 cc of the rising layer of the mixture thus obtained is mixed with 50 cc of the mixture obtained by mixing 25 cc of water glass and 25 cc of water to prepare a mixture of 100 cc. Divide this into two shares, use the first share for the amount B, and leave the remaining share.

A and B were mixed, so that the liquid solidified in 50 seconds. On the other hand, the neglected share was frozen in 80 minutes.

(Experiment 2)

This was injected into the ground consisting of the irradiation layer and the fine sand layer in Tokyo.

First, the liquid A and the liquid B described in relation to Experiment 1 were respectively supplied by separate pumps at a rate of 10 l / min and joined by a Y-tube, and the combined AB liquid was injected into the ground through an injection pipe. When the injection amount of AB liquid reached about 200 L, supply of A liquid was stopped and only 400 L of B liquid were injected.

Excavation was performed after the injection was completed. As a result, the irradiation layer was found to be solidified with water glass mixed with cement, while the fine sand layer was almost filled with a gel of water glass not mixed with cement. That is, it was confirmed that the ground into which the high binder of the present example was injected is solidified in a mass.

Example 6

The injection test under high pressure was carried out on soft ground formed from mud in Tokyo.

First, a hole with a diameter of 100 mm was drilled in the ground to a depth of 10 m. Then, an external pipe having a diameter of 90 mm (having an open end for injecting A liquid into a pipe on the bar) is inserted into the hole, and the liquid B is inserted into an inner tube closed end wall having a diameter of 40 mm. And a nozzle to be injected) are inserted isometrically into the outer shell to form a double tube. In more detail, two nozzles are provided at the end of the inner tube of the double tube so that the B liquid is ejected at right angles to the long contraction of the injection tube, and the inner tube has an outer portion with its end protruding from the open end of the outer tube. It is inserted in. The high resolution (ie, A and B solutions) to be injected is prepared as follows.

Preparation of A

400 kg of cement and 40 g of bentite are combined with water to obtain 1 m 3 of the mixture.

Preparation of B

250 l of water glass and 334 l of ethylene glycol acetate (coagulant) are combined with water to obtain 1 m 3 of the mixture.

(This mixture freezes in about 60 minutes).

The liquid in which the liquid A and liquid B are thus combined is solidified within about 40 seconds.

Now, the liquid B was injected while rotating the inner tube under high pressure of 200 kg / cm 2, while the liquid A was also injected through the appearance under the pressure of 10 kg / cm 2 at the same time. In this operation, the ground is cut and relaxed by a jet of strong B liquid, and at the same time, the liquid A is cut and injected through the relaxed portion, and consequently, the liquid A at the cut and relaxed portion of the ground. And B are to be joined. This process is carried out with the double tube gradually upwards. The cut and loosened parts soon solidified, forming a solid cylinder.

As a result of the ground inspection by excavation, the circumferential solidified body exceeded 30cm in diameter, most of which consisted of cement mainly, and the rest of which was substantially formed of water glass. It was found that the ground improved. This fact substantially means that A liquid penetrates into the coarse soil layer as a solid substance, and B liquid penetrates into the fine grain soil layer and solidifies. The strength of the solidified portion showed an axial compressive strength of 80 kg / cm 2 according to the laboratory test, and there was no deviation of B liquid. That is, all of the injected solidified liquid solidified, and thus there was no danger of causing pollution problems such as water pollution.

Example 7

In the same manner as in Example 6, the method of the present invention was titrated on a soft ground (particularly a leaky ground) of a slit vaginal clay layer in Tokyo, Japan.

First, five holes were drilled in a straight line with a diameter of 100 mm and a depth of 10 m at a distance of 80 cm. Two injection tubes were prepared, one (hereinafter referred to as A tube) having a diameter of 40 cm, an open end, and the other (hereinafter referred to as B tube) having a diameter of 40 cm, but with an end closed. Two nozzles are provided at positions opposite to each other on the closed end wall. These two injection tubes were inserted into each hole in parallel with each other, but the lower end of the B tube having the nozzle hole was positioned deeper than the lower end of the A tube, and the nozzle hole was positioned toward the excavated adjacent hole.

In the present Example, A liquid and B liquid which were used in Example 6 were used as it is.

Now, the liquid B was injected into the ground at a pressure of 200 kg / cm 2 through each B pipe, and at the same time, the liquid A was pressed into the ground at a pressure of 5 kg / cm 2 through the A pipe. In this work, the ground was cut and relaxed in a straight line connecting the above five holes due to the high-pressure injection of the liquid B, and thus the liquid A and the liquid B were injected and joined at this part.

The cutting and relaxation work of the ground by the injection and confluence of the liquid A and the liquid B is gradually carried out by gradually raising the pipes A and B. In other words, the cutting and the loosening parts are solidified and are 30 cm wide and 4 m long. A conjunctiva was formed.

According to the excavation test, this solid membrane is formed by cement solidification within 10 cm of the central part, and in other parts by solidification mainly with water glass. It was formed into a homogeneous, unified solidified body (composite grout) to fully achieve index. This fact indicates that the coagulating solution mainly composed of liquid A penetrated into the coarse soil layer, and that the coagulating liquid mainly containing liquid B penetrated into the fine granulated soil layer. The strength of the freezing portion showed an axial compressive strength of about 80㎏ / ㎠ according to the indoor test.

Moreover, no trace of deviation of solution B was found at all, and both solution A and solution B were solidified, and thus there was no danger of causing pollution problems such as water pollution.

Example 8

The example which applied to the tunnel construction of this invention, achieves the earth effect and the exponential effect, and excavates the tunnel stably.

First, 8 horizontal holes with a length of 10m were drilled at a circumferential position of 5m in diameter with a central axis of 8m depth on the ground surface. Subsequently, the double pipes used in Example 6 are respectively inserted into the eight holes. In this case, each of the double pipes is placed with one steel bone-column material.

As the injection liquid, liquid A and liquid B used in Example 6 were prepared, and as in Example 6, liquid B was first ejected without rotation through the inner tube of the double tube at a high pressure of 200 kg / cm 2, and at the same time, liquid A Injecting the AB liquid to join and slowly pull out the double tube from the hole, but the steel bone for reinforcement was left as it is.

As a result of the excavation inspection after completing the injection according to the present invention, a columnar solid body mainly composed of cement mortar having a diameter of about 30 m in the horizontal direction centered on the drilled hole was formed. Since this columnar solidified body maintains the steel frame inside, it acts as a burial material and has a great strength.

This is the reason for the earth beams, and moreover, substantially solid water glass mainly extends continuously between columnar solids to form an exponential region. Thus, the present invention was able to smoothly perform the tunnel construction to safely excavate the soil inside by giving the earth effect and the exponential effect in the tunnel construction at the same time.

Furthermore, according to the present invention, the steel frame can be put in the hole before the confluence of the A and B liquids into the hole. In other words, first, A and B are injected into the hole, and the steel for the salvage can be hammered into the hole before the solidifying agent is added.

Claims (1)

As described above, in the case of mixing and injecting A liquid, which is a mixture of water and a binder, and B liquid, which is an aqueous glass solution containing a binder, A and B are mixed at the same time. How to freeze soft ground, characterized in that.