JPS58222210A - Ground injection work and injection pipe therefor - Google Patents

Abstract

PURPOSE:To prevent the adhesion of gelled substances to an injection pipe by a method in which an expandible bag is attached to the nozzle port of the inner tube of a multiple injection tube and the nozzle port of the outer tube is opened or closed by expanding or shrinking the bag by the supply or discharge of a liquid. CONSTITUTION:When boring water is sent from the flow path 2a of an outer tube 2, the water flows out by pushing down a ball valve 10 through the lower nozzle port 9, and thereby the ground is excavated. Then, when a water glass solution or a mixture of water glass and a reactant is sent from the flow path 2a and a aqueous reactant solution is sent concurrently from the flow path 1a of the inner tube 1, an expandible bag 3 is expanded by the pressure of the fluid to close the flow path 2a. Further, the aqueous reactnat solution expands the sleeve 7 of rubber from the nozzle port 6 of the inner tube, spouts to the flow path 2a, and is mixed with the water glass solution or the mixture of water glass and reactant. The mixture is jetted from the upper nozzle port 8 of the outer tube 2 to the outside of the outer tube 2 and injected into the ground.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a ground injection method for injecting liquid into the ground by using multiple injection pipes and freely converting the outlet of the injection pipe, and the injection pipe used in this method. The geotechnical technique is widely used, in which multiple fluids are sent into the ground using an injection pipe with multiple channels, and the fluids are combined and solidified, thereby solidifying the ground.

To give an example, this method uses an injection pipe with a plurality of flow paths, first, the polling water is sent to the injection pipe to drill an injection hole in the ground, and then the plurality of injection pipes are A plurality of injection materials are sent separately through the channel, and these are combined and injected into the ground from the outlet on the side wall of the injection pipe as instant setting grout, or they can be combined outside the injection pipe. This is a so-called composite injection method in which permeable grout is injected into the ground separately from the outlet, and then the permeable grout is injected from the outlet at the bottom of the injection tube. It is necessary to have a conversion function.

Conventionally, the discharge port in the injection pipe was changed (switched) by operating a valve using a spring, but when switching the discharge port, gelled substances adhered to the spring, making the valve inoperable. It had the following drawback.

In order to improve the drawbacks of the above-mentioned known techniques, the inventor of the present invention, as a result of intensive research, attached an elastic bag to the discharge port of the inner tube of the injection tube, and applied the expansion or contraction effect of the elastic bag due to changes in fluid pressure. The present invention has been developed by improving the drawbacks of the above-mentioned known techniques.

The object of the present invention is to provide a ground injection method that uses multiple injection pipes, freely converts (or switches) the discharge ports of these injection pipes, injects the injection liquid into the ground, and also prevents the occurrence of sticking due to gelled substances. Another object of the present invention is to provide an injection pipe for use in this construction method.

In order to achieve the above-mentioned object, according to the ground injection method of the present invention, a multiple injection pipe having a plurality of discharge ports is inserted into the ground, and then a plurality of pipes are inserted into the ground from the discharge port through a plurality of pipes in the multiple injection pipe. In the ground injection method of injecting an injected liquid into the interior, the inner pipe of the inner pipe and outer pipe constituting the multiple injection pipe is provided with an inner pipe discharge port, and an elastic bag is provided at or near the tip of the inner pipe. At the same time, a communication hole is bored in the tip of the inner tube where the elastic bag is provided or in the tube wall near the tip, and the inside of the elastic bag and the inner tube conduit communicate with each other via the communication hole. In addition, the outer tube is provided with a plurality of discharge ports at different positions in the axial direction, and when injecting, the multiple injection tube is used to perform the following [A], which is not yet [A'l and [ f3] 'eIt is characterized by being injected by arbitrary combinations.

[A] By sending the injection liquid through the pipe line including the inner pipe line, the elastic bag is expanded by the fluid pressure of the inner pipe injection liquid, and one of the plurality of discharge ports of the multiple injection pipe is inflated by the fluid pressure of the inner pipe injection liquid. Part of the discharge port is closed, and the injected liquid in the inner tube is discharged from the inner tube outlet to the outside of the inner tube, and the injected liquid in the outer tube is squeezed by the elastic bag. An injection method in which injection is performed into the ground through another discharge port that is not closed.

[B] By sending the injection liquid through a conduit that does not include an inner pipe line, the injection liquid can be delivered from any of the outlet ports without the outlet ports of the multiple injection tubes being closed by elastic bags. An injection method in which the material is press-fitted into the ground.

Furthermore, according to the injection tube of the present invention, it is a multiple injection tube having a plurality of discharge ports and comprising at least an inner tube and an outer tube, wherein the inner tube is provided with an inner tube discharge port, and a distal end thereof is provided with an inner tube discharge port. An elastic bag is provided at or near the tip of the inner tube, and a communication hole is bored in the tube wall at or near the tip of the inner tube where the elastic bag is provided, so that the inside of the elastic bag and the inner tube can be connected to each other. The outer tube is characterized in that the outer tube is provided with a plurality of discharge ports at different positions in the axial direction.

Hereinafter, the present invention will be explained in detail using the accompanying drawings.

1 to 8 are specific examples of injection pipes used in the ground injection method according to the present invention.

First, to explain using Figure 1 (a, b) k,
1 is an inner pipe, la is a pipe (or flow path) of the inner pipe 1, 2 is an outer pipe, and 2a is a pipe (or flow path) of the outer pipe. The injection tube in this example is composed of an inner tube 1 and an outer tube 2, and an elastic bag 3 is provided at the distal end of the inner tube 1. A communication hole 4 is bored, and the interior 5 of the elastic bag 3 and the pipe line 1a of the inner tube 1 are covered with a tube 7 through the communication hole 4. An upper discharge port 8 and a lower discharge port 9 are provided at different positions in the axial direction, that is, at positions above and below the elastic bag 3, respectively.

The aforementioned elastic bag 3 is, for example, a rubber bag. In FIGS. 1(a) and 1(b), 10 is a ball valve, and 11 is a spring, and the ball valve 10 operates as a check valve by the action of the spring 11. Also,
12 is a metal crown, and 13 is a rubber umbrella check valve.

When installing the injection pipe constructed in this way, first,
As shown in FIG. 1(a), drilling water is fed through the channel 2a of the outer tube 2 to drill holes in the ground. At this time, the flow path 1a of the inner tube 1
Since no fluid is sent to the elastic bag 3, the elastic bag 3 is not inflated.
Therefore, the flow path 2a is not closed by the elastic bag 3, and the drilling water passes through the lower discharge port 9 to the ball pulp 1.
Press 0 down and it will flow out in the direction of the arrow.

Next, a water glass aqueous solution or a mixture of water glass and a reactant is fed from the flow path 2a of the outer tube 2, and at the same time, a reactant aqueous solution is fed from the flow path 2a of the inner tube 1, so that the reactant aqueous solution communicates. The elastic bag 3 is reached through the hole 4, and the elastic bag 3 expands due to the fluid pressure, thereby closing the flow path 2ai of the outer tube 2. Furthermore, the reactant aqueous solution pushes out the rubber sleeve 7 through the inner tube discharge port 6 and is ejected into the flow path 2a, and mixes with the water glass aqueous solution or the mixed liquid of water glass and the reactant, and the mixed liquid is transferred to the upper part of the outer tube. It is ejected from the discharge port 8 to the outside of the outer pipe 2 and injected into the ground. (Figure 1(b)). That is, the fluid passing through the flow path 2a is switched from the lower discharge port 9 to the upper discharge port 8.

Another construction example will be shown using FIG. That is,
A blended solution having a long gelation time, which is a mixture of water glass and a reactant, is fed through the channel 2a of the outer tube 2, and the channel 1 of the inner tube 1
Send the quick-setting agent from a. These two liquids are mixed in the conduit 2a of the outer pipe 2 in the same way as described above to form a liquid mixture with a short gelation time, and this liquid mixture is injected into the ground from the upper discharge port 8 of the outer pipe 2, and this liquid is injected into the ground. It fills in the gaps in the tube spool and also fills in the rough or weak areas around it. Next, when the feeding of the quick-setting agent from the inner tube 1 is stopped, the flow path 2a is unstretched and closed due to the expansion of the elastic bag 3, and therefore the flow path 2a is unstretched and closed.
The mixed liquid having a long gelation time fed into a is converted into a flow path from the upper outlet 8 of the outer tube 2 to the lower outlet 9, and is injected into the ground from the lower outlet 9.

The injected mixed liquid with a long gelling time will not deviate to the ground surface and will spread around the surrounding area because the mixed liquid with a short gelling time has already been filled and solidified into the voids, rough areas, or weak areas around the upper discharge port. It penetrates between soil particles and solidifies the ground homogeneously.

As is clear from FIG. 2(a), the injection tube in FIG. 2 is composed of an inner tube 1 and an outer tube 2, and the inner tube 1 has an upper inner tube outlet 6
In addition, the inner tube has a lower discharge port 14, and an elastic bag 3 is provided on the tube wall near the tip of the inner tube, and a communication hole 4 is bored in the tube wall where the elastic bag 3 is provided. The interior 5 of the elastic bag 3 and the channel (flow path) la of the inner tube 1 are connected to each other through a communication hole 4ff. An upper discharge port 8 and a lower discharge port 9 are provided at different positions in different directions, that is, at positions above and below the elastic bag 3, and other than that, the structure is almost the same as that of the injection tube in FIG. 1a. ing.

An example of the construction process for this type of press-fit pipe is as follows.

First, as shown in FIG. 2(a), water is introduced from the inner pipe channel 1a to poll the ground, and the injection pipe is inserted at a predetermined depth. After the polling water is discharged from the inner pipe lower discharge port 14 and the injection pipe is installed at a predetermined position, the water supply is stopped and the ball valve 15 is inserted into the flow path la as shown in Fig. 2 (bl). The ball pulp 15 falls and closes the lower discharge port 14 of the inner tube.

Next, as is clear from FIG. 2 (1)), when a fluid containing a reactant is introduced from the channel 1a and a fluid containing water glass and a reactant is introduced from the channel 2a, first, the elasticity The bag 3 expands due to fluid pressure and closes the flow path 2a of the outer tube 2, and as a result of this closing, the lower discharge port 9 and the upper discharge port 8 are separated, and the fluid from the flow path 1a is inside. The rubber sleeve 7 is pushed out from the tube discharge port 6, and the liquid flows into the flow path 2a of the outer tube 2.
Here, a fluid containing water glass and a reactant from the flow path 2a,
The reactant spouted from the inner tube outlet 6 mixes to form a grout with a short solidification time, and the grout (mixed liquid) is discharged from the upper outlet 8 of the outer tube to the outside of the injection tube and injected into the ground. , solidify the void around the injection pipe and the surrounding ground.

Next, when the supply of the fluid containing the reactant is completely stopped from the flow path 1a, and the mixed liquid containing water glass and the reactant that has a long gelation time is introduced from the flow path 2a, as shown in FIG. 2 (C) □: 111 As shown in FIG. 2, the stretchable bag 3 contracts to open the channel 2ai, so that the blended liquid having a long gelation time is injected into the ground through the lower discharge port 9 of the outer tube 2. At this time, since the upper ground area has already been consolidated by the mixed liquid injected from the upper discharge port 8, the mixed liquid uniformly infiltrates and solidifies between the soil particles without deviating upward.

In Fig. 2 (C), the compounded liquid with a long gelling time is also injected into the ground from the two-part discharge port 8 of the outer tube, but the grout with a short gelling time is injected into the ground around it. Since the grout is filled with a gelled material, most of the compounded liquid (grout) which has a long gelling time is injected into the ground from the lower discharge port 9.

As is clear from FIG. 3(a), the injection tube shown in FIG. 3 has a plurality of upper discharge ports 8 located above the elastic bag 3, and a plurality of lower discharge ports 9 in the outer tube tube. Several on the wall,
The structure is similar to that shown in FIG. 2 except that it is provided at the same height as the elastic bag 3.

When constructing this type of injection pipe, first, water is sent from the inner pipe flow path 1a, this water is ejected from the inner pipe lower discharge port 14 to poll the ground, and the injection pipe is inserted to a predetermined depth. (Figure 3(a)).

Next, when the supply of water is stopped and the ball valve 15 is dropped from the upper part of the injection pipe into the inner pipe flow path la, this ball pulp 15 blocks the lower part of the inner pipe outlet 14 (Fig. 3 (b)
).

Furthermore, when a fluid consisting of a reactant is fed into the inner tube flow path 1a, the fluid expands the elastic bag 3, and the lower discharge ports 9, 9...9 of the outer tube 2 are exposed to the expanded elastic bag 3. The sex bag 3 closes the inner tube, and the fluid in the inner tube is discharged from the inner tube outlet 6 into the outer tube. At the same time, when water glass or a fluid containing water glass and a reactant is introduced from the outer tube flow path 2a,
This fluid is the reactant spouted from the inner pipe outlet 6 and the flow path 2a.
The grout (mixed liquid) is mixed inside and has a short solidification time, and the mixed liquid is discharged to the outside of the injection pipe from the upper discharge ports 8, 8...8 of the outer pipe and injected into the ground. Consolidate the void around the injection pipe and the surrounding ground. (Figure 3(b))'.

Next, the feeding of the fluid containing the reactant from the inner tube flow path 1a is stopped, and the mixed liquid containing water glass and the reactant (
When only the grout (with a long solidification time) is sent, the elastic bag 3 contracts and is injected into the surrounding ground from the lower discharge ports 9, 9, . . . 9 of the outer pipe. (Figure 3 (cl).

At this time, the mixed liquid can also be injected from the upper discharge ports 8, 8, . . . is injected into the ground from the lower discharge ports 9, 9...9.

As shown in FIGS. 4(a) and 4(b), the injection tube of FIG. 3 (the lower outlet at this position is indicated by 9), and is also provided at a position below the elastic bag 3 (the lower outlet at this position is indicated by 93). , when the elastic bag 3 expands and closes the outer tube flow path 2af, the outer tube flow path 2a above the elastic bag 3 and the outer tube flow path 2a''f below the elastic bag 3.
r: The structure is the same as that shown in FIG. 3 except that the connecting pipe 1b is provided on the inner wall of the outer pipe 2.

1 When constructing this type of injection pipe, first, as shown in Fig. 3(a), water is pumped through the inner pipe channel 1a and the ground is bored.
Insert the injection tube to the specified depth. (Not shown.) Next, after stopping the water transfer, the ball valve 15 is dropped from the upper part of the injection pipe into the inner pipe flow path la, and the lower part of the inner pipe discharge port 14 is blocked by this ball valve 15. Figure (a))
.

Furthermore, when a reactant is fed into the inner tube flow path 1a, this reactant enters the inside 5 of the elastic bag 30 through the communication hole 4, expands the elastic bag 3, and expands to the same height as the elastic bag 3. The located lower discharge ports 9,9, . . . 9 are closed by the inflated elastic bag 3, and the fluid in the inner tube is discharged from the inner tube outlet 6 into the outer tube. At the same time, when water glass or a fluid containing water glass and a reactant is fed from the outer tube flow path 2a, this fluid mixes with the reactant discharged from the inner tube outlet 6 in the flow path 2a, resulting in a short solidification time. It becomes grout (mixture),
The mixed liquid is injected into the ground from the upper discharge ports 8, 8...8 of the outer pipe, and simultaneously passes through the connecting pipe 16 and enters the elastic bag 3.
reaches the outer pipe flow path 2a below the lower discharge ports 9a, 9a.
...It is also injected into the ground from 9a, solidifying the void around the injection pipe and the surrounding ground. (Figure 4(a)).

Next, if you stop feeding the reactant from the inner tube l flow path 1a and feed only the mixed solution containing water glass and the reactant (grout with a long solidification time) from the outer tube flow path 2a, the expansion and contraction will occur. As the sex bag 3 contracts, the mixed liquid flows through the lower discharge ports 9, 9. ...
9 injected into the surrounding ground (Fig. 4 (C) and (
d)).

At this time, the above-mentioned mixed liquid is also injected from the upper discharge ports 8, 8...8 and the lower discharge ports 9a, 9a...9a of the outer tube, but the grout around these has a short solidification time. Since it has already been filled, most of the mixed liquid is injected into the ground from the lower discharge ports 9, 9...9.

The injection tube in FIG. 5 is the same as that shown in FIG. 4 except that in addition to the elastic bag 3 shown in FIGS. 5(a) and 5(b), another elastic bag 3a is arranged at intervals. It's the same. Fifth
In the figure, 4a is a communication hole, and 5a is the middle part of the elastic bag 3a.

When constructing this injection pipe, see Figure 5 (al, (b)).
As is clear from FIG. 4 fa) and (b), the upper discharge ports 8°8...8 and the lower discharge ports 9a, 9a
...A blended liquid with a short solidification time is injected from 9a, and then from Fig. 5 (C to (Fig. 4 fc as is clear from di))
, tai, grout with a long solidification time is injected from the lower discharge ports 9, 9, . . .

As shown in FIGS. 6(a) and 6(b), the injection tube in FIG. 6 has an inner tube outlet 6 provided below the elastic bag 3, and an upper outlet 8,8... 8 is provided at the same height as the elastic bag 3, and the lower 1 stop outlet 9a
This is the same as Fig. 4 except that there is no .

When constructing this injection pipe, first, as in FIG. 3(a), water is sent through the inner pipe channel 1a to poll the ground, and the injection pipe is inserted to a predetermined depth. (Not shown.) Next, the supply of water is stopped, and the ball valve 15 falls from the upper part of the injection pipe into the inner pipe flow path la, and the lower inner pipe discharge port 14 is closed by this ball valve 15.

(Fig. 6(a,).) When a reactant is further introduced into the inner tube flow path 1a, this reactant enters the interior 5 of the elastic bag 3 through the communication hole 4 and inflates the elastic bag 3. The upper discharge ports 9, 9, . . . 9 located at the same height as the elastic bag 3 are closed by the expanded elastic bag 3, and the fluid in the inner tube is discharged from the inner tube outlet 6. Discharge into the pipe.

At the same time, when water glass or a fluid containing water glass and a reactant is fed from the outer tube flow path 2a, this fluid passes through the communication tube 16 and reaches the outer tube flow path 2a below the elastic bag 3, where it reaches the outer tube flow path 2a below the elastic bag 3. It is mixed with the reactant discharged from the inner pipe discharge port 6 to form grout with a short solidification time, and is injected into the ground from the lower discharge ports 9, 9...9, solidifying the void around the injection pipe and the surrounding ground. conclude. (Fig. 6(a), (b)).

Next, if we completely stop feeding the reactant from the inner tube flow path 1a and feed only the liquid mixture containing water glass and the reactant (grout with a long solidification time) from the outer tube flow path 2a, the elastic bag 3 contracts, and the liquid mixture flows through the upper discharge ports 8, 8. ...Injected into the surrounding ground from 8. (6:1:, II.

Figure (C), f(1)).

At this time, most of the mixed liquid is injected into the ground from the soil discharge ports 8, 8...8 for the same reason as mentioned above.The injection pipe in Figure 7 is as shown in Figure 7(a). Inner pipe flow path
This is the same as in FIG. 1, except that a middle pipe 17 is further provided inside a, and a discharge port 8 of the middle pipe 17 is provided on the wall of the inner pipe 1. In addition, in FIG. 7, 17a is a flow path of the middle tube 17, and 19 is a rubber sleeve that covers the discharge port 18.

When constructing this type of injection pipe, first, as shown in FIG. 7(a), excavation water is fed through the channel 2a of the outer pipe 2 to drill a hole in the ground. This hole is the same as the injection tube shown in FIG.

Next, when the water glass aqueous solution is fed through the channel 2a of the outer tube 2 and the quick-setting reactant is fed through the channel 1a of the inner tube 1a, the quick-setting reactant is passed through the communication hole 4 into the elastic bag. 30 inside 5
The fluid pressure causes the elastic bag 3 to expand and close the flow path 2a of the outer tube 2.Furthermore, the quick-setting reactant is released from the inner tube outlet 6 through the rubber tube. :.

The ribs 7 are expanded and ejected into the channel 2a, where it is mixed with the water glass aqueous solution to form a liquid mixture with a short solidification time, and the liquid mixture is ejected to the outside of the outer tube 2 from the outlet 8 at the upper part of the outer tube. It is injected into the ground, filling the voids around the injection pipe and filling any rough or weak areas around it.

(Figure 7(b)). After a long time, the feeding of the quick-setting reactant from the inner tube 1 is stopped, and at the same time, the slow-setting reactant is fed from the channel 17a of the middle tube 17. From rubber sleeve 19
is expanded and ejected into the flow channel 2a, where it mixes with the water glass aqueous solution to form a liquid mixture with a long solidification time, and furthermore, the flow channel 2a is unstretched and closed due to the expansion of the elastic bag 3. The liquid mixture having a long solidification time in the flow path 2a is injected into the ground from the lower discharge port 9 of the outer tube 2. (Figure 7 (
C)). The injected mixture with a long consolidation time has already been filled and consolidated with the mixture with a short consolidation time in the voids, rough areas, or weak areas around the upper discharge port, so it will not deviate to the ground surface and will spread to the surrounding area. Penetrates between soil particles and solidifies the ground homogeneously.

The injection tube of FIG. 8 further includes an intermediate tube 17 in the inner tube flow path la, and a discharge port 18 of the intermediate tube 17 is provided in the wall of the inner tube 1, as shown in FIG. 8(a). It is the same as Fig. 3 except for the following. In addition, in FIG. 8, 17a is the middle pipe 17.
The flow path 19 is a rubber sleeve that covers the discharge port 18.

When constructing this type of injection pipe, the flow path 17 of the middle pipe 17
Water is sent in from a to poll the ground, and the injection pipe is inserted to a predetermined depth. (not shown).

Next, stop supplying water, and enter the middle pipe flow path 17a from the injection pipe A section.
When the ball valve 15 is dropped inside, the middle pipe lower discharge port 14f is closed.

Furthermore, when a fluid consisting of a quick-setting reactant is introduced into the inner tube flow path 1a, the elastic bag 3f expands, and the outer tube 2
The lower discharge ports 9, 9, . . . 9 are closed by the inflated elastic bag 3, and the fluid in the inner tube is discharged from the inner tube discharge port 6 into the outer tube. At the same time, the outer tube flow path 2a
When a water glass aqueous solution is introduced from the inner pipe outlet 6, this fluid mixes with the rapid setting reactant ejected from the inner tube outlet 6 in the channel 2a to form a grout (mixed liquid) with a short setting time, and the mixture The liquid is discharged to the outside of the injection pipe from the upper discharge ports 8.8...8 of the outer pipe and injected into the ground, solidifying the void around the injection pipe and the surrounding ground. (Figure 8(a)).

Next, when the supply of the fluid consisting of the quick-setting reactant from the inner tube flow path 1a is completely stopped, the elastic bag 3 contracts and the flow path 2a is unfastened and closed, and then the flow path 17a of the middle tube 17 is released. When a fluid consisting of a slowing reaction agent is introduced from the discharge port 18, this fluid pushes the rubber sleeve 19 apart and is ejected into the channel 2a, where it mixes with the water glass aqueous solution in the channel 2a. The liquid mixture takes a long time to solidify, so this liquid mixture is injected into the ground from the lower discharge ports 9, 9, . . . 9 of the outer pipe 2. (
Figure 8(b)).

The press-fit tube in FIG. 9 is different from the one in which the inner tube outlet 6 is provided in the outer wall of the outer tube 2 at a location close to the upper outlet 8 of the outer tube, as shown in FIG. 9(a). Same as Figure 2.

In addition, in FIG. 9, 7a is an on-off valve for the inner tube discharge port 6, which replaces the rubber sleeve 7 in FIG.

When constructing this type of injection pipe, first, as shown in Fig. 2 (a), the flow path 1axF of the inner pipe 1) is to save water and drain the ground.
Insert the J-song and injection tube to the specified depth. (Not shown.) Next, the water supply is stopped and the ball valve 1 is inserted into the flow path 1a.
5, and this ball valve 15 closes the lower discharge port 4 of the inner tube.

Next, as shown in FIG. 9(a), a fluid containing a reactant (rapid setting reactant) is fed from the channel 1a, and water glass and a reactant (slow setting reactant) are fed from the channel 2a. When a fluid containing .
The flow path 2af is closed, and the lower discharge port 9 is closed again.
and the upper discharge port 8 are separated, and the fluid from the flow path 1a is pushed and spread from the inner pipe discharge port 6 to the on-off valve 7ai and flows into the outer pipe 2.
The fluid from the flow path 2a is also discharged from the upper discharge port 8 to the outside of the outer tube 2, and both are mixed on the outside of the injection tube to form a grout with a short solidification time, and the fluid around the injection tube is The void and surrounding ground will be completely consolidated.

Next, when the feeding of the fluid containing the reactant from the flow path 1a is stopped, and the mixed liquid containing water glass and the reactant with a long solidification time is fed from the flow path 2a, as shown in FIG. 9(b). ,
As shown in FIG. 2(C), the elastic bag 3 contracts and then opens the flow path 2a, so the liquid mixture with a long initial solidification time is injected into the ground through the lower outlet 9 of the outer tube 2. Ru. At this time, since the upper ground area has already been consolidated with the grout which has a short consolidation time, the blended solution which has a long consolidation time does not deviate upward and is uniformly infiltrated between the soil particles and solidified.

In the injection tubes shown in Figures 1 to 9, the fluids used are classified as follows: OA = water glass aqueous solution B: a mixture of water glass and reactant (mixed in a mixer) (It may be a liquid, or it may be a liquid in which a water glass aqueous solution and a reactant aqueous solution are combined at an arbitrary point or point.) B': Water glass and acid are mixed and the PH value of the mixed liquid is in the acidic to neutral range. A mixture.

C: Cement suspension D: Reactant aqueous solution E: Carbon dioxide The combinations that combine and solidify these fluids are A-C, A-
D%A-ElB-C1B-D, BE.

There are CD, etc., especially in the case of B', B'-C, B'-1
) (alkaline aqueous solution), B'-A, B"-C, B
'-(mixture of C and D) B'-B (when the pH of the mixture is in the alkaline range), etc.

In the above, since carbon dioxide gas is a gas, it can be mixed into A'- or B and gelled without changing the water glass concentration, and it has the advantages of high strength, gelling in a short time, and ease of construction. Very good at
, and this carbon dioxide gas is also suitable for inflating the elastic bag in the present invention.

The ball pulp used in the present invention may be in the form of a ball or in the form of a cone or other closed bundles.

Examples of the reactants in the present invention include acids (inorganic acids, organic acids, etc.), salts (inorganic salts, organic salts, basic salts, neutral salts, acid salts, etc.), esters, aldehydes, amides, alcohols, Any material can be used, such as alkalis such as lime, cement, etc., but is not limited to these. In addition, as for water glass, the molar ratio (S iOz/
MzO): 1.5 to 5.0 An alkali metal salt of silicic acid in any molar ratio, including liquid water glass, anhydrous water glass, hydrous water glass, crystalline water glass, etc., or an alkali metal salt of silicic acid and A mixture of silicic acids is used.

Example 1 Test injection was carried out using the injection pipe shown in Fig. 1 in the ground consisting of alternating layers of sandy sand layer, fine sand layer, sill I/clay layer from the surface layer up to 107FI.

The composition of the injection solution is as follows.

A: Gel time per 100 m 30 minutes B: After inserting the carbon dioxide gas injection tube f 10 m deep, 1 minute from the outer tube.
::,1 Liquid A was fed at a rate of 10 t/min, and was ejected from the inner tube at an injection pressure of 9 atmospheres of fiBi, and was injected from the bottom to the top of the stage. The injection stage was set at every 5C1cIn, and the injection amount of liquid A was set at every stage.

The silty clay layer at the bottom and the sandy clay layer at the top are A.
: Only injection of 8 combined liquid was performed, and for the intermediate fine sand layer, after 501 injections of A:8 combined liquid at each stage, the merging of B was stopped, and A
Only the liquid was injected 507 times.

A: The gelation time of the 8 confluence was 5 seconds.

An excavation survey revealed that the silty clay layer had penetrated into fine veins and solidified. In addition, the fine sand layer was filled with instant-setting gel around the injection tube, and was solidified homogeneously by liquid A. Example 2 Test injection was carried out on sandy ground using the injection pipe shown in Figure 2.

The composition of the injection liquid is as follows: O A: 100/- per B: ] 00 per C,: 100 is inserted into the depth of the injection pipe f10 m and the lower discharge port of the inner pipe is closed. Afterwards, pA liquid is added to the Y-shaped tube attached to the upper end of the outer tube, and equal amounts of C liquid are combined from the inner tube, and the combined liquid i 1s 17
After injecting from the outer tube for 1 minute, stop injecting C from the inner tube,
Bi was joined from the other side of the Y-tube, and equal amounts of both solutions A and 8 were injected, and the stage was raised from the bottom to the top. The injection stage is every 50 crn, and the injection volume per stage is 1.
At 00 t, A:C combined liquid (A at the time of i750 injection)
: Switched to 8 combined liquid and injected 50.

The gelation time for the A:8 combined solution was 1 minute, and the gelation time for the A-C combined solution was 4 seconds.

As a result of the excavation investigation, the entire sand and gravel layer was solidly consolidated, and no deviation outside the injection range was observed.Example-3 Test using the injection pipe shown in Figure 3 in fine sandy ground mixed with silt. injection was performed.

The composition of the injection solution is as follows.

A: 16% by weight sodium bisulfate aqueous solution OB = mixed solution prepared by adding 40% by weight of water glass to sulfuric acid and adjusting the pH to 3,
Gelation time: 2 hours.

C: After inserting the 10 wt% water glass aqueous solution injection tube to a depth of 'jjOm, take injection stages every 50z and add 10 tons of liquid A from the outer tube per stage.
After injecting the A:C combined liquid 'i50, the injection of the A:C combined liquid was interrupted, and the B liquid was pumped at 10t/min from the outer tube. Injected with.

The gelation time of the A:C combined solution was 7 seconds.

An excavation survey revealed that the entire injected ground was homogeneously consolidated.

Despite the long gelation time of solution B, no deviation of the injected solution was observed.

[Brief explanation of drawings]

Figure 1 (al, (b), Figure 2 (a), (b)
, (C), Figure 3 (a). (1)), (C1, Fig. 4 (al, (b),
(C1', (d), Figure 5 (a), (b). (C), (di, Figure 6 (a), (b), (C),
(d), Figure 7 (al, (b). (C), Figure 8 (a), (b+, Figure 9 (a),
(1)) shows a specific example of the press-fit pipe according to the present invention and a process diagram of the construction method according to the present invention, respectively. 1... Inner tube, 1a... Inner tube flow path, 2... Outer tube, 2
a... Outer tube flow path, 3, 3a... Elastic bag, 4, 4a
...Communication hole, 5.5a...Inside of elastic bag, 6...
・Inner tube discharge port, 7.19...Rubber sleeve, 7a...
・Opening/closing valve, 8... Outer tube upper discharge port, 9.9a... Outer tube lower discharge port, 10.15... Ball pulp, 14.
... Inner pipe 1 part discharge port, 16 ... Connecting pipe, 17 ... Middle pipe, 17a ... Middle pipe flow path, 18 ... Middle pipe discharge port Patent applicant Shima 1) Shun calculation ( (1) (1) (C) )3rd rc) $5 area) θ area ((L) (C) 譈9 (α) pi)

Claims (1)

[Scope of Claims] 1. A ground injection method in which a multiple injection pipe having a plurality of discharge ports is inserted into the ground, and then injected liquid is injected into the ground from the discharge ports through a plurality of pipes in the multiple injection pipe. Of the inner tube and outer tube constituting the multiple injection tube, the inner tube is provided with an inner tube discharge port, and an elastic bag is provided at or near the distal end, and the inner tube provided with the elastic bag is provided with an inner tube outlet. A communication hole is bored in the tube wall at or near the tip of the tube, and the inside of the elastic bag and the inner tube conduit are connected to each other via the communication hole, and the outer tube has a shaft. A plurality of discharge ports are provided at positions in different directions,
A ground injection method characterized in that the multiple injection pipes are used for injection according to the following [A] or an arbitrary combination of [A] and [B]. [A] By sending the injection liquid through the pipe line including the inner pipe line, the elastic bag is expanded by the fluid pressure of the inner pipe injection liquid, and one of the plurality of discharge ports of the multiple press-fit pipe is expanded. Part of the discharge port is closed, and the injected liquid in the inner tube is discharged from the inner tube outlet to the outside of the inner tube, and the injected liquid in the outer tube is squeezed by the elastic bag. An injection method in which injection is performed into the ground through another discharge port that is not closed. [B] By sending the injection liquid through a conduit that does not include an inner pipe line, the injection liquid can be delivered from any of the outlet ports without the outlet ports of the multiple injection tubes being closed by elastic bags. An injection method in which water is injected into the ground. 2. The ground injection method according to claim 1, in which the inner pipe discharge port is provided at a position above and/or below the elastic bag. In the ground injection method described in , the injection liquid in the inner pipe is discharged into the outer pipe line, where the injection liquid in the inner pipe and the injection liquid in the outer pipe are mixed and injected into the ground. In the ground injection method according to claim 1, the injection liquid in the inner pipe is directly discharged to the outside of the multiple injection pipe,
Method 05, characterized in that the injection liquid in the inner pipe and the injection liquid in the outer pipe are mixed outside the injection pipe.In the ground injection method according to claim 1, the discharge port of the multiple injection pipe is It consists of an upper outlet and a lower outlet, the upper outlet is provided at a position above the elastic bag, and the lower outlet is provided at the same position as or below the elastic bag,
Construction method 06, characterized in that the discharge port in the front lower part is closed by the expansion of the elastic bag.In the ground injection method according to claim 1, the opening tip of the inner pipe is elasticated. A bag is provided, and the inside of the elastic bag and the inner tube conduit are connected to each other via the open tip of the inner tube, and the outer tube is provided with an upper discharge port and a lower discharge convex, and the upper discharge port and the lower discharge convex are provided in the outer tube. The discharge port is provided at a position above the elastic bag, and the lower discharge port is provided at the same position or below the elastic bag so as to be closed by the expansion of the elastic bag. A construction method characterized in that injection is performed using the multiple press-fitting pipes according to the [Aj]. 7% Allowance In the ground injection method described in claim 1, the inner pipe is provided with an elastic bag on the pipe wall near the tip, and the inside of the elastic bag and the inner pipe conduit are connected to the inner pipe. The inner tube is connected to each other via a communication hole provided in the tube wall near the tip, and is provided with an inner tube outlet on the tube wall above the elastic bag and the lower tip, and an upper outlet on the outer tube. An outlet and a lower discharge port are provided, the upper discharge port is provided at a position υ above the elastic bag, and the lower discharge port is connected to the elastic bag so as to be closed by expansion of the elastic bag. It is provided at the same or lower position, and prior to injection, drilling water is first supplied to the inner pipe, and the drilling water is discharged from the inner pipe outlet at the lower tip to drill the hole, and then the lower tip is drilled. A construction method characterized in that the discharge port of the inner pipe is closed, and then the injection is performed using the above-mentioned [Aj]. 8. The ground injection method according to claim 6 or 7, characterized in that the [Aj and the CB] are used together. 9. A multi-injection tube having a plurality of discharge ports and comprising at least an inner tube and an outer tube, wherein the inner tube is provided with the inner tube discharge port, and has a stretchable tube at or near its tip. A bag is provided, and a communicating hole is bored in the tip of the inner tube where the elastic bag is provided, or in the tube wall in the vicinity thereof, and the inside of the elastic bag and the inner tube conduit are connected through the communicating hole. 2. The injection pipe for use in the ground injection method according to claim 1, wherein the outer pipe is connected to each other via a rope, and the outer pipe is provided with a plurality of discharge ports at different positions in the axial direction. 10. The injection tube according to claim 10, wherein the inner tube discharge port is provided at a position above and/or below the elastic bag. 11. In the injection tube according to claim 10, the outlet of the multiple injection tube consists of an upper outlet and a lower outlet, and the upper outlet is provided at a position above the elastic bag, The injection tube is characterized in that the lower discharge port is provided at the same position as or below the elastic bag so as to be closed by the expansion of the elastic bag. I2. In the injection tube according to claim 10, an elastic bag is provided at the open tip of the inner tube, and the inside of the elastic bag and the inner tube conduit are connected to the open tip of the inner tube. The outer tube is provided with an upper outlet and a lower outlet, the upper outlet is located above the elastic bag, and the lower outlet is connected to the elastic bag. An injection tube provided at the same position as or below the elastic bag so as to be closed by the expansion of the bag. 13 In the injection tube according to claim 10, an elastic bag is provided on the tube wall near the tip of the inner tube, and the inside of the elastic bag and the inner tube conduit are connected to the inner tube near the tip. An inner tube outlet is provided in the tube wall above the elastic bag and a lower tip, which communicate with each other via a communication hole provided in the tube wall, and an upper outlet and a lower outlet are provided in the outer tube. an outlet is provided, the upper outlet is provided at a position above the elastic bag, and the lower outlet is located at the same position as or below the elastic bag so as to be closed by the expansion of the elastic bag. The injection tube is provided in the inner tube, and the inner tube outlet at the lower tip is closed by falling into the inner tube.