JPH033769B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a ground injection method particularly suitable for injecting rock, earth and sand into the ground.

When constructing dams, tunnels, etc., to stop water or solidify the ground, cement or various types of solidifying chemicals are usually injected into the ground. is used. As this kind of police car equipment,
Rubber packers, air packers, etc. are used. During injection, these packers are used to close only one location in the hole and the injection material is injected into the stratum below, or the single packer method uses these packers to seal only one location in the hole and injects the material into the stratum below. The double packer method is used, which involves closing the trench and injecting the injection material into the strata in the gap.

For example, as shown in Fig. 1, an injection pipe A equipped with an air bag C is inserted into a bore hole If the gap E formed between the pipe A and the hole wall D is closed by the inflated air bag C, and the injection material is injected into the stratum below the air bag C in this state, the injection material This prevents the liquid from overflowing upward along the hole wall D.

However, in the method using the injection pipe A described above, the air bag C is inflated by air supply, which not only complicates the process, but also requires that the injection pipe A be equipped with an air supply hose B. Furthermore, the injection pipe A
In addition, an air supply source such as an air cylinder must be installed separately, and the equipment becomes complicated.

SUMMARY OF THE INVENTION An object of the present invention is to provide a ground injection method which uses very simple equipment and is easy to operate, and which overcomes the drawbacks of the above-mentioned known techniques.

In order to achieve the above object, according to the ground injection method of the present invention, an injection hole is drilled in the ground, an injection pipe is inserted into the injection hole, and then the injection pipe is moved to set the injection stage. In the ground injection method in which the injection material is injected into the ground from the discharge port of the injection pipe while changing the injection pipe, an elastic bag is covered in a band shape around the outside of the injection pipe wall. A communication hole is formed in the wall of the elastic bag to communicate the inside of the elastic bag with the flow path of the injection tube, and the injection material passing through the injection tube flow path during injection is formed through the communication hole. This inflow pressure causes the elastic bag to expand and close the gap between the injection tube and the hole wall of the injection hole, and the injection material is discharged from the discharge port. The injected material is injected into the ground, so that the inflated elastic bag prevents the injected material from overflowing along the wall of the injection hole.

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

FIGS. 2 to 9 each show an explanatory view of the injection pipe according to the present invention and the ground injection method according to the present invention using this injection pipe.

First, to explain Fig. 2, 1 is the inner pipe,
1a is a flow path of the inner tube 1, 2 is an outer tube, and 2a is a flow path of the outer tube 2. The injection tube A in this example is composed of an inner tube 1 and an outer tube 2, and an elastic bag 3, such as a rubber bag, is covered in a band shape around the outside of the injection tube wall. A communication hole 4 is provided in the covered tube wall to connect the inside 5 of the elastic bag 3 and the flow path of the injection tube A, that is, the flow path 2a of the outer tube 2.
is drilled. In addition, in FIG. 2, 6 is the discharge port of the outer pipe 2, 7 is the injection hole drilled in the ground, 8 is the hole wall of the injection hole 7, and 9 is the injection pipe A and the hole wall 8.
10 is the inner pipe discharge port, 11 is the valve, 1
2 is a spring, and 13 is a metal crown.

When constructing the injection pipe having the above-mentioned configuration, first, as shown in FIG. 2a, the flow path 1a of the inner pipe 1 is
Excavation water is sent from the outlet through the discharge port 10 to drill holes in the ground.

Next, as shown in FIG. 2b, the flow path 2 of the outer tube 2 is
When the injection material (grout) is sent from a, the injection material flows into the elastic bag 3 through the communication hole 4,
Due to this inflow pressure, the elastic bag expands and the injection tube A
The gap 9 between the injection hole 7 and the hole wall 8 of the injection hole 7 is closed, and the injection material in the flow path 2a is injected into the ground from the discharge port 6. At this time, the inflated elastic bag 3 prevents the injection material from overflowing upward along the hole wall 8 of the injection hole 7. Note that when the discharge port 6 is provided at a position below the elastic bag 3 as shown in the second figure, the injection material is prevented from overflowing upward along the hole wall 8 as described above. The position of the discharge port 6 does not necessarily need to be provided below the elastic bag 3, and may be provided above. In this case, the injection material is prevented from spilling downward. In addition, if the outer periphery of the injection tube A covered by the elastic bag 3 is formed in a concave shape as shown in the second figure, when the injection tube A is inserted into the injection hole 7, the elastic bag 3 will touch the hole wall 8. This is preferable because it will not be destroyed by contact.

Incidentally, using the injection pipe shown in the second figure, during or after injection of the injection material from the discharge port 6, the same type of injection material or a different type of injection material as described above may be injected from the discharge port 10 through the flow path 1a.

Next, the ground is easily and firmly consolidated by repeating the above steps while moving the injection pipe A and changing the injection stage.

FIG. 3 shows an example of an injection tube having a plurality of elastic bags, in which elastic bags 3,
3a are respectively covered in a band-like manner at intervals, and insides 5, 5a of the elastic bags 3, 3a are respectively covered on the tube wall covered by these elastic bags 3, 3a.
and communication holes 4, 4a that communicate the flow path 2a with each other.
are perforated, and a discharge port 6 is provided in the tube wall between these elastic bags 3, 3a.

When constructing an injection pipe with such a configuration, first, a hole is drilled in the ground in the same manner as shown in Figure 2a (3).
Figure a), then as shown in Figure 3b, when the injection material is delivered from the channel 2a of the outer tube 2, this injection material passes through the communication holes 4 and 4a and enters the elastic bags 3 and 3a. This inflow pressure causes the elastic bags 3, 3 to
a expands to form the gap 9 in FIG. 3a, respectively.
9a is closed, and the injection material is injected into the ground from the discharge port 6. The injected material is prevented from overflowing upward or downward by the action of the expanded elastic bags 3, 3a, and is well injected into a predetermined stage of the ground. The rest is the same as the example shown in FIG.

FIG. 4 shows that two upper communicating holes 4' and two lower communicating holes 4'' are bored at the upper and lower positions of the tube wall covered by the elastic bag 3, and in addition to the discharge port 10 of the inner tube 1. An example of an injection pipe provided with another discharge port 10a covered with a rubber band 15 is shown.

According to this type of injection pipe A, during construction, first, as shown in Fig. 4a, excavation water is sent from the flow path 1a of the inner pipe 1, and after drilling, the inner pipe is drilled as shown in Fig. 4b. The ball valve 14 is dropped into the flow path 1a of the tube 1 to close the flow path 1a, and then, as shown in FIG. When each liquid is sent, flow path 1
The reactant aqueous solution of a is pushed open the rubber band 15 and is discharged from the discharge port 1a into the channel 2a, and the water glass aqueous solution in the channel 2a enters the interior 5 of the elastic bag 3 from the upper communication hole 4'. to inflate the elastic bag and pass through the lower communication hole 4'' to the check valve 16.
is pushed open and flows down, mixed with the reactant aqueous solution from the inner pipe 1, and injected into the ground from the discharge port 6.
In this type of injection tube, the fluid in the channel 2a is constantly flowing and does not stay in the elastic bag 3, so instead of the water glass aqueous solution, a grout that can solidify itself, such as water, is used. A mixture of glass and a reactant, cement grout, etc. can also be used. The rest is the same as the example shown in FIG.

Figure 5 shows two elastic bags 3, 3 as in Figure 3.
a are covered at intervals, and the discharge port 1 of the inner pipe 1
0a shows an example of an injection tube led to the outside of the injection tube A. For example, a reactant aqueous solution is fed to the flow path 1a of the inner tube 1, and a water glass aqueous solution is fed to the flow path 2a of the outer tube 2. Once liquidized, both liquids are mixed outside the injection tube A, which is particularly suitable for injection of instant setting grout with a short setting time. The rest is the same as the example shown in FIGS. 3 and 4 described above.

6 is similar to the injection tube in FIG. 4, except that the discharge port 10 located at the tip of the inner tube 1 in FIG. 4 is closed and does not exist.

In FIG. 7, there is a middle tube 1' between the inner tube 1 and the outer tube 2, a discharge port 10 is provided at the tip of the middle tube 1', and other parts are arranged around the outer wall of the injection tube A. As in the example shown in FIG. An example of an injection pipe provided with a discharge port 10a leading to the flowchart is shown. In addition, in Fig. 7, 4b is a communication hole,
5b is the inside of the elastic bag 3b.

When constructing this type of injection pipe, first, as shown in Fig. 7a, drilling water is sent from the channel 1'a of the middle pipe 1' to drill a hole, and then, as shown in Fig. 7b, for example, When the main material aqueous solution is sent through the channel 2a and the reactant aqueous solution is sent through the channel 1a, the elastic bag 3 is expanded by the main material aqueous solution and closes the gap 9, and the elastic bag 3b also contains the reactant aqueous solution. The main material aqueous solution is further discharged from the discharge port 6 to the outside of the injection pipe, and the reactant aqueous solution is also discharged from the discharge port 10a to the outside of the injection pipe, so that both liquids are mixed and injected outside the injection tube, as in the example shown in FIG.

Fig. 8 is almost the same as Fig. 4 except that the inner tube 1 is configured to protrude beyond the outer tube 2 at the distal end, and the protruding distal end of the inner tube 1 is further covered with an elastic bag 3a. An example of an injection tube with a similar structure is shown. In the figure, 6a is a discharge port at the tip of the inner tube 1. When constructing this type of injection pipe, excavation water is sent from the channel 1a to drill a hole in the ground (not shown).
As shown in FIG.
When the mixed aqueous solution (main material) of water glass and reactant is sent from the channel 1a, the reactant aqueous solution flows through the communication hole 4a.
penetrates into the interior 5a of the elastic bag 3a through the elastic bag 3a, expands the elastic bag 3a, closes the outlet 6a of the outer tube 1, closes the gap 9, and pushes the rubber band 15 open. The material is discharged from the outlet 10a of the inner tube 1 into the channel 2a of the outer tube 2, and the main material from the channel 2a enters the interior 5 of the elastic bag 3 through the upper communication hole 4' and is discharged from the outlet 10a of the inner tube 1. expands and closes the gap 9, flows downward from the lower communication hole 4'', mixes with the reactant aqueous solution from the flow path 1a in the flow path 2a, and flows from the discharge port 6 to the ground as a mixture of both liquids. injected inside.

Next, as shown in FIG. 8b, when the feeding of the reactant aqueous solution from the flow path 1a is stopped, the discharge port 6a and the gap 9 are opened, and only the main material from the flow path 2a flows from the discharge port 6a into the ground. is injected into. The rest is the same as each example described above.

In FIG. 9, a single tube has a discharge port 6 at the tip thereof, and a closure portion 17 above the discharge port 6, and an elastic bag 3 is provided on the tube wall near the closure portion 17. An example of an injection tube is shown in which an upper communicating hole 4' and a lower communicating hole 4'' are respectively formed at the upper and lower positions of the closing portion 17 in the tube wall covered by the elastic bag 3. show.

When installing this type of injection pipe, when grout is sent through the channel A1 of the injection pipe A, the grout enters the interior 5 of the elastic bag 3 through the upper communication hole 4'.
The fluid pressure of this grout expands the elastic bag 3 to close the gap 9, and the grout passes through the lower communication hole 4'' and is injected into the ground from the discharge port 6.Others are the same as in each of the previous examples. be.

In addition, in each of the above examples, the injection hole 7 means a hole formed by drilling (boring),
It may also be a casing that has been bored.

As mentioned above, the present invention uses very simple equipment and can be easily operated, and can be said to be a practically extremely useful ground injection method.

[Brief explanation of the drawing]

Figure 1 shows a cross-sectional view of a known injection pipe and an example of its construction; Figures 2a and b; Figures 3a and b;
Figures a, b, c, Figure 5, Figure 6, Figure 7 a, b,
FIGS. 8a and 8b and FIG. 9 respectively show a process explanatory diagram of the method of the present invention and a sectional view of an injection pipe used in the method of the present invention. A... Injection pipe, 1... Inner tube, 1a... Channel in inner tube, 2... Outer tube, 2a... Channel in outer tube, 3,3
a, 3b...Elastic bag, 4, 4a, 4b...Communication hole, 4'...Upper outlet, 4''...Lower outlet,
5, 5a, 5b...Inside of elastic bag, 6, 6a...
... Discharge port, 7... Injection hole, 8... Hole wall, 9... Gap, 10, 10a... Discharge port of inner tube.

Claims (1)

[Claims] 1. An injection hole is drilled in the ground, an injection pipe is inserted into the injection hole, and the injection pipe is moved to change the injection stage while the injection hole is inserted into the ground from the discharge port of the injection pipe. In the ground injection method in which the injection material is injected into the interior of the injection pipe, a stretchable bag is covered in a strip around the outside of the injection pipe wall, and the pipe wall covered with the stretchable bag is covered with the stretchable bag. A connecting hole is formed to connect the inside and the flow path of the injection tube with each other, and the injection material passing through the injection tube flow path during injection flows into the elastic bag through the communication hole,
The elastic bag is expanded by this inflow pressure to close the space between the injection pipe and the hole wall of the injection hole, and the injection material is injected into the ground from the discharge port. Accordingly, the inflated elastic bag prevents the injected material from overflowing along the hole wall of the injection hole. 2. In the ground injection method according to claim 1, the discharge port of the injection pipe is provided at a position below the elastic bag, so that the inflated elastic bag can be used as the injection pipe. A construction method for preventing the poured injection material from overflowing upward along the hole wall of the injection hole. 3. In the ground injection method according to claim 1, the outside circumference of the injection pipe wall is covered with a plurality of stretchable bags in a band shape and spaced apart, and further the plurality of stretchable bags A construction method in which a discharge port is provided on the wall of the injection pipe between the pipes. 4. In the ground injection method according to claim 1, a plurality of communication holes are drilled at upper and lower positions of the pipe wall covered by the elastic bag, whereby the elastic bag A construction method in which the injected material flows from the upper communicating hole to the lower communicating hole.