JPS61145280A - Stabilization of ground - Google Patents

Abstract

PURPOSE:To quickly control the concn. by switching sodium silicate to water during injection in separately supplying an aq. soln. of sodium silicate and a curing agent to a plurality of plunger pumps, mixing the delivered solutions and injecting the mixture into the ground to stabilize it. CONSTITUTION:Carbon dioxide gas 1 as a curing agent is mixed with water 6 in a mixer 5 and the pressurized carbonic acid water obtd. is separately supplied to plunger pumps 14A and 14B of a four cylinder-type grout injection pump 14. Aqueous soln. of sodium silicate is separately supplied to plunger pumps 14C and 14D of the injection pump 14. Then the pressurized carbonic acid water delivered from the pumps 14A and 14B is combined with the aq. soln. of sodium silicate delivered from the pumps 14C and 14D and supplied to a mixer 2, and the obtd. grout is injected into the ground to stabilize it. The concm. of sodium silicate is instantly controlled by switching part of the sodium silicate soln. 16 to water during injection in response to conditions of the ground.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for stabilizing the ground using a grout made of a mixture of sodium silicate and a hardening agent that can harden this grout in the ground.

Specifically, while grout is continuously injected into the ground, the gel time and sodium silicate concentration of the grout are instantly changed to match the ground conditions.

This invention relates to a method of stabilizing the ground using eaves in various ways more advantageous than in the past.

(Prior Art) Conventionally, as a method of stabilizing the ground with grout made of a mixture of sodium silicate and a hardening agent that can gel in the ground, it has been used in advance before construction.

Sodium silicate and a hardening agent are mixed into an aqueous solution (the hardening agent may be in the form of a suspension) in a concentration suitable for construction in a dedicated mixing tank (stirring tank). ) and a hardening agent (hereinafter referred to as liquid B) are poured into the ground while being mixed in a suitable mixer during construction.

A method of hardening in the ground is generally adopted.

In this type of construction method, while grout is continuously injected into the ground, it often becomes necessary to change the gel time and sodium silicate concentration of the grout depending on the ground conditions. In technology, when changing the gel time of grout, add a curing agent or water to the B liquid mixing tank to increase or decrease the curing agent concentration in the B liquid,
And when changing the sodium silicate concentration in the grout.

A commonly used method is to add sodium silicate or water to a liquid A mixing tank to increase or decrease the concentration of sodium silicate in liquid A.

(Problems to be Solved by the Invention) However, with this method, the gel time and sodium silicate concentration of grout actually change after grout raw materials are added to the A-liquid mixing tank, B-liquid mixing tank, etc. It takes more or less time to do this, depending on the scale of the equipment such as the capacity of the mixing tank, so it is important to instantly change the gel time and sodium silicate concentration while pouring grout into the ground to match the ground conditions. I can't.

Therefore, in order to improve this point, the present inventors previously published a grout using a combination of sodium silicate and carbon dioxide gas in Japanese Patent Application Laid-Open No. 58-204213.

In order to instantaneously change the gel time during grout injection into the ground, we proposed a method of adding water to a mixer that mixes both liquids A and B during grout injection into the ground.

According to this method, during the ground injection of grout.

The gel time can be changed instantaneously,
In this method, 1. Usually, water is simply added to the A and B mixture (grout) and the amount is increased or decreased, so as the gel time of the grout changes, the amount of grout injected into the ground (injection speed) also changes. Resulting in.

That is, in this method, it is usually not possible to change the gel time of the grout while keeping the amount of grout injected into the ground constant.

(Means for Solving the Problem) In view of the above circumstances, the inventors of the present invention stabilized the ground using a grout that combined sodium silicate and a hardening agent that could harden in the ground.

Even when the amount of grout injected into the ground is fixed, various studies have been conducted in an attempt to improve the invention described in 9% JP-A No. 58-204213 so that the gel time and sodium silicate concentration can be changed instantaneously during the injection into the ground. Result 2 The present invention described next was achieved.

That is, the present invention according to this application consists of the three inventions described below. In this method, liquids A and B are mixed in the mixer to form a grout raw material, and then the obtained grout is injected into the ground and hardened in the ground to stabilize the ground. After dividing the supply to each supply port of a grout injection pump consisting of a plurality of mutually moving plunger pumps, the discharged liquids iA and B are combined and supplied to the mixer, and then the grout Stabilization of the ground, which is characterized by switching part of the A liquid dividedly supplied to the grout injection pump into water during injection, depending on the ground conditions, and further switching this water back to A liquid as necessary. Law.”

The second invention is [liquid A consisting of an aqueous sodium silicate solution].

Supply each of Part B containing hardener to a total mixer.

Producing grout by mixing both in the mixer,
Then, inject the obtained grout into the ground.

In the method of stabilizing the ground by hardening it in the ground,
In advance, liquids A and B are dividedly supplied to each supply port of a grout injection pump consisting of a plurality of plunger pumps that move relative to each other, and then the discharged liquid is used as A.

The B liquids are combined together and supplied to the mixer, and during the grout injection into the ground, a part of the B liquid dividedly supplied to the grout injection pump is switched to water as appropriate depending on the ground conditions, and further water is added as necessary. A method for stabilizing the ground characterized by switching this water back to liquid B according to the situation,” and the third invention is “
A solution A consisting of an aqueous sodium silicate solution and a solution B containing a curing agent are each supplied to a mixer, and the two are mixed in the mixer 1 to produce grout, and the resulting grout is then applied to the ground. In the method of stabilizing the ground by injecting it and hardening it in the ground, liquids A and B are previously dividedly supplied to each supply port of a grout injection pump consisting of a plurality of plunger pumps that move relative to each other.

The discharged liquids are combined into liquids A and B and supplied to the mixer, and during grout injection into the ground, a part of liquids A and B, which were separately supplied to the grout injection pump described in -1-, is added to the ground. A ground stabilization method characterized by switching to water as appropriate depending on conditions, and further switching this water to liquids A and B again as necessary. ” is the gist.

The present invention will be described below with reference to two drawings.

FIG. 1 is a flow sheet showing an embodiment of the present invention in which carbon dioxide gas is used as the curing agent. First, the common parts of the above three inventions will be explained. Carbon dioxide storage tank l (usually a liquefied carbon dioxide cylinder is used).

) and carbon dioxide and water from the water storage tank 6 f! c.Supplied to the first mixer 5.

At this time, the flow of carbon dioxide gas is regulated by the control valve 4, and the carbon dioxide gas flowing out from the carbon dioxide storage tank 1 is allowed to pass through the evaporator 3 to vaporize the accompanying droplets.

The first mixer 5 is a container with a sealed pressure-resistant structure, and is provided with any device such as a stirrer, a jammer plate, etc. for improving contact mixing of gas and liquid.

As shown in the figure, the first mixer 5 is equipped with a propeller-type agitator, but the present invention is not limited to such a shape, but can be a turbine-type, fan-turbine-type, or curved-blade turbine. A mold, Faudler type, pullmargin type or any other type of stirrer can also be used.

In addition, the first mixer 5 is a mixer in which a stationary fluid stirring element is provided.

A so-called line mixer (pipe mixer) or a packed column packed with packing to improve gas-liquid contact is also preferably used, but any type of mixing device can be used. In any case, it is desirable to use a mixer equipped with a mixing mechanism with high stirring efficiency so that the supplied carbon dioxide gas and water can be mixed in as short a time as possible.

The carbon dioxide gas and water supplied to the first mixer 5 are mixed in the mixer to produce pressurized carbonated water (carbonated water in a pressurized state due to the supplied carbon dioxide gas), but this is not the case. ,
Increase the pressure (-amount) of carbon dioxide gas supplied to the mixer (-
The more concentrated carbonated water can be produced in the mixer, the more concentrated carbonated water can be produced.

9. In the present invention, the pressurized carbonated water (Liquid B) thus produced and the sodium silicate aqueous solution previously charged in the sodium silicate storage tank 16 are each injected into each suction port of the four-barrel grout injection pump 14. supply

The four-motion grout injection pump 14 used in the present invention is a grout injection pump commonly used in this type of chemical injection method, and the grout injection pumps 14 move relative to each other.

It consists of four plunger pumps (also referred to as reciprocating pumps or piston pumps) each having an independent liquid suction port and discharge port.

At this time, the pressurized carbonated water is dividedly supplied to the inlets ■ and ■ of the four-bar plunger pump 14 via the switching valve 9, and at the same time, the sodium silicate aqueous solution is supplied from the storage tank 16 to the switching valve 17.
It is then dividedly supplied to the suction ports (■) and (■) of the four-bar plunger pump 14.

(At this time, the switching valves 11, 12 and 15 are closed in advance, and the switching valves 13 and 18 are opened.) In the present invention, both the sodium silicate aqueous solution and pressurized carbonated water are In this process, it is essential to separately supply the liquid to each suction port of a grout injection pump consisting of a plurality of plunger pumps that move relative to each other.
At a minimum, a 4-tube grout injection pump is used, but of course it is not limited to only 4-bars, and may be a 5-tube type, a 6-tube type, or a multiple pump type of more than that, as appropriate. A grouting pump can also be used.

In addition, in Figure 1, since a 4-port grouting pump is used, the sodium silicate aqueous solution and pressurized carbonated water are each dividedly supplied to the same number (2) of plunger pumps. In the present invention, the sodium silicate aqueous solution and the pressurized carbonated water do not necessarily need to be separately supplied to the same number of plunger pumps. For example, if a five-port grouting pump is used, the sodium silicate aqueous solution is supplied to three plunger pumps. It is also possible to divide pressurized carbonated water into two plunger pumps,
It is also possible to do the opposite.

Furthermore, since a normal plunger pump can change its discharge amount in several stages, the discharge amount d of each plunger pump in the quadruple grout injection pump 14 is not necessarily equal, but is different from each other. It is also possible to increase the discharge amount.

As the sodium silicate used in the present invention, sodium silicate No. JISa, which has been conventionally used for stabilizing the ground, is usually suitably used.
A value higher than No. 83 sodium silicate, ranging from 3 or more to 5 or less, can also be used.

During construction, these sodium silicate solutions are diluted with water to form an aqueous solution with an appropriate concentration suitable for ground stabilization. In the present invention, the concentration of the sodium silicate aqueous solution charged into the sodium silicate aqueous solution storage tank 16 is usually 20 to 100. It is desirable to set the capacity to 1.

In this way, the sodium silicate aqueous solution and the pressurized carbonated water, which are dividedly supplied to each supply port (each plunger pump) of the four-barrel gracto injection pump 14, are transferred to the sodium silicate aqueous solution and the pressurized carbonated water at each discharge port. The water is combined and supplied to the second mixer 20.

The aqueous sodium silicate solution and pressurized carbonated water supplied to the second mixer 20 are usually stored in the mixer for an instant because the mixer is built into the grout injection pipe 19 and has a water capacity. It is mixed, grouted and injected into the ground.

The common parts of the three inventions of this application have been explained above, but in the first invention of this application, while grout is continuously injected into the ground in this way,
A portion of the sodium silicate aqueous solution dividedly supplied to each of the supply ports (1) and (2) of the four-port grout injection pump 14 is switched to water as appropriate depending on the ground conditions.

That is, in the first invention, at the same time when the switching valves 11 and 15t are opened during grout injection into the ground, the switching valve 1 is opened.
Close 8. As a result, the 4-port grouting pump 1
Water is supplied to the supply port 4 instead of the sodium silicate aqueous solution, and the second mixer 20 is supplied with a reduced concentration sodium silicate aqueous solution while maintaining the original flow rate.

Then, this sodium silicate aqueous solution is instantaneously mixed with pressurized carbonated water in the second mixer 20, turned into grout, and injected into the ground. During ground injection, the concentration of sodium silicate in grout can be reduced instantaneously without changing the injection amount.

In this embodiment, initially, the sodium silicate aqueous solution was separately supplied to each of the suction ports (1) and (2) (ie, the plunger pumps 14c and t4I) of the quadruple grouting pump 14.

Since the liquid supplied to the suction port (■) is then converted to water, if the discharge amounts of the plunger pumps 14c and 14D are equal, the concentration of sodium silicate in the grout after being converted to water will be the same as the initial concentration. / 2, but if such a large drop in concentration is not desirable, the discharge amount of the plunger pump 14c should be made smaller than the discharge amount of the plunger pump 14D from the beginning, or in the case of FIG. Unlike.

The sodium silicate aqueous solution is divided in advance into 3 or 4, or even more, using three or more plunger pumps, and the - of the two is then divided.

You can take measures such as switching to water.

While grout with a lower sodium silicate concentration is injected into the ground in this way, if you wish to return the sodium silicate concentration to its original level depending on the ground conditions, you must perform the operation opposite to that described above, that is, use the switching valve. 11 and 15 are closed, and at the same time, the switching valve 18 is opened. Added to this is a 4-port grouting pump 1
The sodium silicate aqueous solution is again supplied to the supply port 4, and
The sodium silicate concentration in the grout instantly becomes the same as at the beginning.

Therefore, according to the first invention of this application, while grout is being continuously injected into the ground, the injection i.
The sodium silicate concentration in the grout can be instantly lowered by simple valve operation without any change, and the concentration can then be instantly returned to its original state. .

Normally, such valve operations can be performed all at once by moving the answer.

Next, in the second invention of this application, during grout injection into the ground, a portion of the pressurized carbonated water dividedly supplied to each of the supply ports ■ and ■ of the four-barrel grout injection pump 14 is supplied depending on the ground conditions. In this case, the switching valves 11 and 12 are opened and the switching valve 13 is closed at the same time as the grout is being poured into the ground.

As a result, water is supplied instead of pressurized carbonated water to the four-way grouting pump 14 supply port (2), and the second mixer 20
is supplied with pressurized carbonated water that has been reduced in concentration while maintaining the original flow rate.

This pressurized carbonated water is instantaneously mixed with the sodium silicate aqueous solution in the second mixer 20 for the reason described above, and is turned into grout and injected into the ground, so the above-mentioned measures are taken. By the way.

During grout injection into the ground, the gel time of the grout can be changed instantaneously without changing the injection amount.

In this embodiment, initially, among the pressurized carbonated water dividedly supplied to each of the suction ports ■ and ■ (that is, the plunger pumps 14A and 14B) of the four-way grout injection pump 14, the pressurized carbonated water is supplied to the suction port ■. plunger pumps 14A and 14 because the supply liquid of
If the discharge amount of B is the same, the CO in the grout after the cut pattern is seen in the water will be 1/2 of the initial CO, but if such a drastic decrease in concentration is undesirable, the initial Therefore, the discharge amount of the plunger pump 14B should be made smaller than the discharge amount of the plunger pump 14A, or unlike the case shown in FIG. Divide it into quarters or more.

Measures can be taken such as switching the negative part to water afterwards.

While grout with a changed gel time is being injected into the ground in this way, if the gel time is to be returned to its original value depending on the ground conditions, the operations described above must be reversed, i.e., the switching valves 11 and 12 ( Switching valve 1 at the same time as i7 closes
Open 3. Due to this.

Pressurized carbonated water is again supplied to the suction port (2) of the four-barrel grout injection pump 14, and the gel time of the grout becomes instantaneously the same as the initial state.

Therefore, according to the second invention of this application, the gel time of the grout can be changed instantaneously by a simple valve operation without changing the injection amount while grout is being continuously injected into the ground. The straps can then be instantly returned to the re-strapped state. Such valve operations can be performed all at once by moving the two normal answers.

Next, in the third invention of this application, during grout injection into the ground, the suction port of the quadruple grout injection pump 14 is
Pressurized carbonated water and inhalation 1 dividedly supplied to each of
] Part of the sodium silicate aqueous solution separately supplied to each of ■ and ■ is switched to water as appropriate depending on the ground conditions.
．． In this case, during the grout injection into the ground, the switching valve 11.12
and 15 are opened, and at the same time, switching valves 13 and 18 are closed.

This VC, 1: S, Water is supplied to the suction port ■ of the four-port grout injection pump 14 instead of pressurized carbonated water, and water is supplied to the suction port ■ instead of the sodium silicate aqueous solution. hand,
Second mixer 20V? - While maintaining the original flow rate, pressurized carbonated water and sodium silicate aqueous solution each having a lower concentration are supplied.

And this pressurized carbonated water and sodium silicate aqueous solution.

For the reasons already mentioned, the grout is instantaneously mixed in the second mixer 20, grafted, and injected into the ground. It is possible to instantaneously change the gel time of grout and instantaneously lower the sodium silicate concentration without changing the grout.

Note that this embodiment involves the operation of switching part of the pressurized carbonated water dividedly supplied to each of the suction ports (■) and (2) of the four-barrel grout injection pump 14 described above to water, and This is because the method involves simultaneously performing an operation of switching a portion of the sodium silicate aqueous solution supplied to each of the divided portions to water.

Regarding the CO2 concentration and sodium silicate concentration in the grout obtained after replacing a portion of the pressurized carbonated water and the sodium silicate aqueous solution with water, and the measures to be taken when such concentrations are not adopted, please refer to the respective operations. The same thing can be said about the case.

In this way, while the grout with the gel time changed and the sodium silicate concentration reduced is injected into the ground, the gel time and sodium silicate concentration may be returned to their original values depending on the ground conditions.

The operation is the opposite of the ramp-up operation, ie the switching valves 11, 12 and 15 are closed and the switching valves 13 and 18 are opened at the same time.

As a result, the suction port of the 4-bar grout injection pump 14
Pressurized carbonated water is supplied again to the inlet, and a sodium silicate aqueous solution is again supplied to the suction port (2), and the gel time and sodium silicate concentration of the grout momentarily return to their original states. (In addition.

When returning part of either the CO2 concentration or the sodium silicate concentration in the grout, in the case of the former, the switching valve 12i
At the same time as the switching valve 15 is closed, the switching valve 15 is opened, and in the latter case, the switching valve 18 is opened at the same time as the switching valve 15 is closed. ) Therefore, according to the third invention of this application, while the grout is being continuously injected into the ground, the injection amount can be easily changed, and the gel time and sodium silicate concentration of the grout can be adjusted by a simple valve operation. It can be changed simultaneously and instantaneously, and then it can be returned to the re-string state simultaneously and instantaneously. Such valve operations can be performed all at once by moving the normal answer.

The present invention has been explained above using an example of a silicate grout using carbon dioxide gas as a hardening agent.
The present invention is also applicable to silicate grouts using hardening agents other than carbon dioxide gas.

In addition, although the present invention relates to a silicate grout made of a combination of a silicate and a hardening agent, the basic idea is not limited to just a silicate grout.
All other inorganic and organic two-component glazes) (A, B
It can also be applied to two-component grout.

(Example) A specific example of the present invention was implemented according to the embodiment shown in FIG.

Example 1 A cylindrical packed tower with a diameter of 270 m and a height of 1800 m, the inside of which was filled with Terrarette packing, was used as the first mixer 5, and carbon dioxide gas and water were supplied to this packed tower to pressurize it. Carbonated water was produced.

Next, the obtained pressurized carbonated water is dividedly supplied to each of the suction ports (1) and (2) of the four-barrel grouting pump 14, and at the same time, Na2O4 and 8i are supplied from the sodium silicate aqueous solution storage tank 16.
A sodium silicate aqueous solution containing 0.0215% is dividedly supplied to each of the suction ports (1) and (2) of the four-port grouting pump 14, and the discharged liquid from each outlet is divided into pressurized carbonated water and a sodium silicate aqueous solution. Combine and grout injection pipe 19
(double tube).

The pressurized carbonated water and the aqueous sodium silicate solution supplied to the grout injection pipe 19 were instantaneously mixed in a second mixer 20 built into the injection pipe 19 to form grout.

(Grout ■, Table 1) In the process of continuously injecting the grout thus obtained into the soil ring, the switching valve
At the same time, the switching valves 11 and 12 were opened to supply water instead of the pressurized carbonated water to the suction port (2) of the four-channel grout injection pump 14.

As a result, pressurized carbonated water with reduced concentration was supplied to the grout injection pipe 19, and the gel time of the grout changed instantaneously. (Grout@, Table 1) Test conditions and results obtained are shown in Table 1.

Example 2 The suction amount of pressurized carbonated water at the suction port (■) of the quadruple grout injection pump 14 and the suction amount of the sodium silicate aqueous solution at the suction port (■) were 40% smaller than in Example 1. All tests were conducted in the same manner as in Example 1.

The test conditions and the results obtained are shown in Table 2.

Example 3 The same pressurized carbonated water and sodium silicate aqueous solution used in Example 1 were separately supplied to each suction port of the quadruple grout injection pump 14, and then each discharged liquid was supplied with pressurized carbonated water and a sodium silicate solution. The soda aqueous solutions were combined and supplied to the grout injection pipe 19.

The pressurized carbonated water and the aqueous sodium silicate solution supplied to the grout injection tube (19) were instantaneously mixed in the injection tube to form grout, as in Example 1. (Grout ■, Table 2) During the process of completely continuously injecting the grout thus obtained into the soil, the switching valve 18 is closed, and at the same time, the switching valves 11 and L5f (opened and the quadruple grout injection pump 1
In place of the sodium silicate aqueous solution, water was supplied to the suction port (2) of No. 4.

As a result, a low-concentration sodium silicate aqueous solution was supplied to the grout injection pipe 19, and the sodium silicate concentration in the grout changed instantaneously. (Grout@, Table 2) The test conditions and the results obtained are shown in Table 3.

27-Example 4 After separately supplying the same pressurized carbonated water and sodium silicate aqueous solution as used in the example work to each suction port of the four-barrel grout injection pump 14, each discharged liquid was converted into pressurized carbonated water. The water and the sodium silicate aqueous solution were combined and supplied to the grout injection pipe 19.

The pressurized carbonated water and the sodium silicate aqueous solution supplied to the grout injection pipe 19 were instantaneously mixed in the injection pipe and grouted (grout
, Table 3) During the process of continuously injecting the grout obtained in this way into the soil, the switching valves 11, 12 and 15 were opened, and the switching valves 13 and 8 were simultaneously opened. Water was supplied to the suction port (2) of the gracto injection pump 14 in place of the pressurized carbonated water, and at the same time, water was supplied to the suction port (2) in place of the aqueous sodium silicate solution.

As a result, the grout injection pipe 19 is supplied with pressurized carbonated water and sodium silicate aqueous solution each having a lower concentration.
The gel time and sodium silicate concentration of the grout changed simultaneously and instantaneously.

The test conditions and results are shown in Table 4.

Example 5 As a curing agent aqueous solution, an ethylene carbonate aqueous solution (ethylene carbonate 30 kg/water 200λ) and a sodium bisulfate aqueous solution (NaH80427k) were used instead of pressurized carbonated water.
y/water 2001) and aqueous potassium bicarbonate solution (K HC
A grout injection test was conducted using a method similar to Example 1 using each sample (30 kg Os/2 ooJt water). However, the concentration of the sodium silicate aqueous solution used in Test No. 2 was 1/2 compared to Test Nos. 1 and 3.

The test conditions and the results obtained are shown in Table 5.

Example 6 A grout injection test was conducted in the same manner as in Example 2vC, using the same curing agent aqueous solution as that used in Example 5 instead of pressurized carbonated water. However, as an aqueous solution of potassium bicarbonate, 25 #KHCO11/water at 200°C and water at 00°C.

The test conditions and the results obtained are shown in Table 6.

Example 7 A single potassium carbonate aqueous solution was used as the hardening agent aqueous solution.

And instead of the 4-bar grout injection pump 140, a 6-bar grout injection pump (4-bar grout injection pump 14,
Using a pump with two additional plunger pumps, first divide the aqueous potassium bicarbonate solution into each of its inlets ■, ■, and ■, and the aqueous sodium silicate solution into each of its inlets ■, ■, and ■. A grout injection test was carried out in accordance with each of Examples 1 and 3.

However, the potassium bicarbonate aqueous solution and the sodium silicate aqueous solution used were as follows.

Reference Example: As a hardening agent aqueous solution, a Portland cement suspension (Portland cement 200A9/water 200k) was used.
And instead of the sodium silicate aqueous solution, use Denka ESI'l! , B
Liquid C-i' Inka ES 5ou/Water 2oon +f Inka Setter 60Of' Mixed liquid; Denka E8. Uses Denka Setter (grout material manufactured by Denki Kagaku Kogyo ■).

A grout injection test was conducted in accordance with the method in each of Examples 1 and 3.

All test conditions and results obtained are shown in Table 8.

Comparative Example (Conventional Method) Pressurized carbonated water was produced using the same equipment and method as in Example 1.

Then, the pressurized carbonated water obtained was pumped into the four-barrel grout pump 14.
At the same time, the same sodium silicate aqueous solution f used in Example 1 is supplied from the sodium silicate aqueous solution storage tank 16 to each of the suction ports (1) and (2).
The liquid discharged from each discharge port was combined with the pressurized carbonated water and the sodium silicate aqueous solution and supplied to the grout injection pipe 19 (double pipe).

The pressurized carbonated water and the sodium silicate aqueous solution supplied to the grout injection pipe 19 were the same as in Example 1.

The mixture was instantaneously mixed and grouted in the injection tube.

In the process of continuously injecting the grout obtained in this way into the soil, the pressure (-amount) of carbon dioxide gas supplied to the first mixer 5 is varied according to the conventional gel time adjustment method. The CO2m degree in the pressurized carbonated water was increased or decreased, thereby varying the gel time of the grout.

The test conditions and the results obtained are shown in Table 5.

(Effect of the invention) Since it has already been explained, I will omit it.

[Brief explanation of drawings]

FIG. 1 is a flow sheet showing one embodiment of the present invention. 1 Carbon dioxide storage tank 2, switching valve 3, evaporator 4, flow rate control valve 5, first mixer 6, water storage tank 7, switching valve 8, pump 9, switching valve 10 water storage tank 11, switching valve 12, switching valve 13, switching valve 14, 4-person grout injection pump 14, A plunger pump 14B plunger pump 14c plunger pump 14D plunger pump 15 switching valve 16 sodium silicate aqueous solution storage tank 17 switching valve 18 switching valve 19 grout injection pipe 20 No. Second mixer ■ Suction port of plunger pump 14A ■ ' Discharge port of plunger pump 14A ■ Plunger pump 14
Suction port of B■' Discharge port of plunger pump 1.4B■ 1 adult port of plunger pump 14C■' Discharge port of plunger pump 14c■ Plunger pump 1
4-D [stage inlet ■' of plunger pump 14D]
Exit patent applicant Nitto Kagaku Kogyo Co., Ltd. (2 others) Paralysis 11] Procedural amendment (voluntary) February 12, 1985

Claims (1)

[Claims] 1. A solution A consisting of an aqueous sodium silicate solution and a solution B containing a curing agent are each supplied to a mixer, and the two are mixed in the mixer to produce grout. In this method, the grout is injected into the ground and hardened in the ground to stabilize the ground. In this method, each liquid A and B is dividedly supplied to each supply port of a grout injection pump consisting of a plurality of plunger pumps that move mutually. After that, the discharged liquids are combined into liquids A and B and supplied to the mixer, and during grout injection into the ground, a part of liquid A, which was divided and supplied to the grout injection pump, is mixed depending on the ground conditions. A ground stabilization method characterized by switching to liquid water as appropriate, and further switching this water to liquid A again as necessary. 2. Supply liquid A consisting of an aqueous sodium silicate solution and liquid B containing a curing agent to a mixer, mix them in the mixer to produce grout, and then inject the resulting grout into the ground. In the method of stabilizing the ground by hardening it in the ground, liquids A and B are dividedly supplied in advance to each supply port of a grout injection pump consisting of a plurality of plunger pumps that move relative to each other, and then the discharged liquid is Liquids A and B were combined and supplied to the mixer, and during grout injection into the ground, liquid B was divided and supplied to the grout injection pump.
A ground stabilization method characterized by appropriately switching a part of the liquid to water depending on the ground conditions, and further switching this water to liquid B again as necessary. 3. Supply liquid A consisting of an aqueous sodium silicate solution and liquid B containing a curing agent to a mixer, mix them in the mixer to produce grout, and then inject the resulting grout into the ground. In the method of stabilizing the ground by hardening it in the ground, liquids A and B are dividedly supplied in advance to each supply port of a grout injection pump consisting of a plurality of plunger pumps that move relative to each other, and then the discharged liquid is Liquids A and B were combined and supplied to the mixer, and during grout injection into the ground, A and B were separately supplied to the grout injection pump.
, B. Switch some of each liquid to water as appropriate depending on the ground conditions.
This method of stabilizing the ground is characterized in that the water is then switched back to liquids A and B as necessary.