JPH02261119A - Chemical fluid injection process and device therefor - Google Patents

Abstract

PURPOSE:To prevent the gelation of the chemical fluid by feeding the water from a hose attached to a packer to dilute the circulated chemical fluid, when the chemical fluid is leaked from the reduced clearance of the packers while the packers are being reduced after the chemical fluid has been poured. CONSTITUTION:To a double packer injection pipe 1' of a strainer injection type, a hose to feed water is attached integrally at the upper outside surface of an inner tube 3 through a bracket 20. The water is fed to the inside hollow 6 of the packers 5 to expand the packers 5, and a chemical fluid is poured into the ground from slits of a strainer 12. By reducing the packets 5 after the chemical fluid is poured, the chemical fluid between the packets 5 and 5 is filled to the outer surface of the inner tube 3 after circulating around the packers, and gelated. In this case, the water is fed from the hose 21 to mix the water and the chemical fluid, and to dilute the chemical fluid, and the gelation is prevented. Thus, chemical fluid can be poured smoothly.

Description

[Detailed Description of the Invention] <Industrial Application Field> The disclosed technology is applicable to ground improvement work on soft ground such as near shallow coasts, rivers, lakes, etc. belongs to the technical field in which it is carried out.

<Summary of the gist> The invention of this application involves drilling a predetermined hole in the ground using a casing pipe or the like when injecting an assimilation chemical into the ground during soil improvement work such as soft ground. After the casing pipe is pulled out, a predetermined number of packers, such as double type packers, are expanded and pressed against the inner wall of the drilled hole. A chemical solution in which the chemical solution is spouted out, the chemical solution is injected into the ground, and then the packer is shrunk to perform stub-down, etc., and in the next step, the chemical solution is injected into the ground again. This invention relates to the injection method, and in particular, during drilling, when the injection pipe is moved up and down step by step and the packer expands and contracts, a hose or the like is attached along the outer surface of the inner pipe of the packer at the upper part, etc., to drain water. This invention relates to a chemical injection method that prevents gelation due to leakage of chemical between packers in the packer reduction process by supplying the chemical and dilutes the chemical to enable smooth step-stroke movement of the injection tube.

<Prior Art> As is well known, in Japan, where the national land is limited, the effective use of land is an extremely important issue, and technologies for redeveloping the limited national land are extremely important.

Therefore, increasing the strength of the soft ground around coasts, rivers, lakes, etc. and covering it so that structures such as buildings and tunnels can be constructed is %f3. Various ground improvement techniques have been researched and developed, and many of them have been put into practical use.

Among these methods, the so-called Zand Drain V method and the chemical method in which the chemical solution is injected one by one into the ground (compared to the chemical method, etc.) are used because the chemical solution easily penetrates into the ground. From, again,
Gel time is widely used because of its advantages such as being able to freely lay layers to adjust the equivalent reaction, but on the other hand, it tends to easily penetrate into joints and between layers in the ground, causing pollution problems such as groundwater contamination. Because of the inconvenience that is likely to occur, it is desirable to spray a set amount of chemical solution into the ground in a reliable amount to a set area, and a double packer etc. is installed in the inner pipe installed inside the outer pipe. The so-called double packer I-method and the Lehner injection method have been developed and have been effectively used.

<Problems to be Solved by the Invention> Of these, the two small tube double packer one type of Lehner injection type will be briefly explained with reference to the drawings in Figure 4 and below.
has a predetermined flexibility 1 inside the outer tube 2 having a predetermined flexibility 1
The inner tube 3 of `` is lazily mounted on a shaft, and a double-type packer 5, 5, etc. made of rubber or the like is provided at a predetermined location in upper and lower two stages, for example, through flanges 4, 4. A nozzle 8 of a water supply pipe 7 provided intermittently inside the inner pipe 3 faces the inner cavity 6 of the packer 5, so that each packer 5 can be expanded or contracted to a predetermined value. .

The chemical liquid supply passage 9, which has a ring-shaped cross section between the inner pipe 3 and the water supply pipe 7, is provided with chemical liquid jet ports 10, 10, . Similarly, chemical liquid jet ports 11, 11... are bored in the outer tube, and thin film-like strips 1 to 1 made of a predetermined synthetic resin, such as heat-shrinkable ones, are formed on the outer surface of the outer tube.
A laner 12 is closely attached, and a predetermined number of slits 13, 13, .

When performing ground improvement work to increase the strength of the ground by injecting a predetermined chemical into a predetermined soft ground using the chemical injection pipe 1 having such a structure, first, as shown in FIG. A predetermined casing pipe 15 is driven into the hole to form a drilled hole 16, and a predetermined sealing material 17 is filled into the nucleating agent hole 16 through the casing pipe 15 as shown in FIG. Then, as shown in FIG. 7, the chemical injection tube 1 with each packer 5 in a reduced state is inserted as lazily as possible, and then, as shown in FIG. The pipe 15 is pulled out and sealed so that the seal No. 17 is directly inserted into the drilled hole 16, and the chemical injection tube 1 is placed in the seal 'vJ17.

Then, when the chemical injection pipe 1 is moved up and down in a predetermined manner and stopped at a predetermined step 1, water at a predetermined pressure is supplied from the ground into the water supply pipe 7 shown in FIG. 4, and the water is supplied from the water supply port 8.8. The inner cavity of the packer 5 is filled and the packer 5 is enlarged (1), and as shown in FIG. When the chemical solution is supplied, a certain amount of the chemical solution is ejected from the packer 5.5 through the sealing material 17 between the packers 5.5 and 11.
Laner 2's slot 1-13 to slot 1 via 11...
．． 13..., the chemical solution 18 is injected into the ground as shown in Figure 9.

When the injection of a predetermined amount of the chemical solution 18 is completed, the supply of the chemical solution to the chemical solution supply passage 9 is stopped, and the water supply to the water supply pipe 7 is stopped, as shown in FIG. 10'g. The packers 5, 5 are reduced in size and the chemical liquid injection tube 1 is lowered by a predetermined number of steps 1 to 1 to carry out a step down, and the chemical liquid is injected in the next step.

However, the ground improvement by such chemical injection]
If the gel time of the chemical solution to be injected in step 3 is short (A1, step-down etc. through scaling of the packers 5 and 5 is performed as smoothly as possible, but the gel time of the drug solution is long such as 60 minutes, 120 minutes, etc.) In the case of gel time, as shown in Fig. 10, when the packer 5 is scaled down at the end of the chemical injection at the stubbing stage shown in the figure, the packer 5
, 5 flows downward on the lower side. In b, the upper part wraps around the upper part of the lower packer 5 and turns upside down, and the gel progresses. Depending on the gel time, gluing of the drug solution is promoted, resulting in gel 19
Or, if the drug solution injection tube 1 was tightened and the step down +

Nevertheless, as mentioned above, expansion and contraction of the packer is indispensable between the double packer type Yasu 1 and Lehner injection type Sj/Lehner injection, so its excellent advantages are not lost. There were also some drawbacks.

<Objective of the Invention> The object of the invention of this application is to solve the technical problem of the gluch choke on the upper and lower sides of the packer in ground improvement using a packer such as a double packer single type based on the above-mentioned prior art, and to While taking advantage of the benefits of ground improvement through use, the packer can be expanded and contracted smoothly, the chemical injection pipe can be stepped up and down smoothly, and ground improvement can be performed as per the design. The aim is to provide the construction industry with an excellent chemical injection T method that is beneficial to the field of soil and water technology application.
゜゜〈Means/effects for solving the problem〉 In order to solve the above-mentioned problem, the structure of the defense of this application, which is based on the above-mentioned claims, is to solve the above-mentioned problem. When carrying out improvement work to increase the strength of the ground, etc., a chemical injection pipe that eliminates double packers, etc. is formed in the ground in advance and inserted into the borehole, and each packer is expanded and inserted between the packers through a sealing material. The specified chemical solution is injected into the ground from the outer tube's S1 to the rape tank, and after the chemical injection is completed, the packer is reduced, and during that time, the chemical solution filled between the packers is discharged from the shrinking gap of the packer. If a leak occurs and goes around the outside of the inner tube,
3. Water is supplied through a hose attached to the inner pipe on the packer to dilute the chemical solution that has gone around and gel it for a short period of time. Technical measures have been taken to ensure that the chemical liquid injection pipe can be moved smoothly without being hindered by the chemical injection pipe, and chemical liquid can be injected for ground improvement according to the design h1.

<Embodiment> Next, an embodiment of the invention of this application will be described with reference to FIGS. 1 to 3.

Incidentally, parts having the same features as those in the drawings from FIG. 4 onward will be described using the same reference numerals.

In the embodiment shown in FIG. 1, 1' is one of the central points of the invention of this application? The structure is roughly the same as the drug solution injection tube 1 of the American version shown in FIG. The difference is that a water supply hose 21 is provided integrally with the water supply hose 21, and its lower end is opened or exposed above the upper packer 5.

Therefore, packer 5.5, chemical solution supply, and ground 14
The method of injecting the chemical solution into the ground 14 is substantially the same as the conventional method shown in Fig. 4. Since the drug injection process for each step is the same, we will not explain the implementation process! 8 Cover.

When injecting a chemical into the soft ground 14 as shown in FIGS. 5 to 10 using the chemical injection pipe 1' having such a configuration, a predetermined hole is formed in the ground 14 through the casing pipe 15 as in FIG. Fill the prescribed seal 17 as shown in FIG. 6, insert the chemical liquid injection pipe 1' into the borehole 16 intermittently as shown in FIG. 7, pull up the casing pipe 15, and fill the water supply passage 7 with the prescribed water water is pressurized into the inner cavity 6 of the packer 5, the packer 5.5 is brought into pressure contact with the inner surface of the drilled hole 16 through the outer tube 2, a predetermined chemical solution is supplied to the chemical solution supply passage, and the water is sprayed. When the jet is ejected from the outlet 10 between the packers 5 and 5,
The chemical liquid is injected into the ground 14 from each slit 13 of the strainer 12 through the seal shrine 17 and the spout 11.11 of the outer pipe 2 in the same manner as in the conventional method. When the chemical liquid injection in the step is completed, it is introduced into the water suction passage 7. By stopping the supply of water, each packer 5, 5 shrinks, and the chemical liquid between the packers 5, 5 goes around the packer and tries to fill the outer surface of the inner tube 3. In particular, the third As shown in the figure, this tendency is strong in the step-down method; in the lower packer 5, the chemical liquid flows downward, but in the upper packer 5, the chemical liquid flows to the upper part of the packer 5. Inner tube 3
The outside of the gel is filled and gelation begins to proceed.

Therefore, by supplying water at a predetermined flow rate to the hose 21 during the packer shrinking process at the step-down timing, the water from the hose 21 is transferred to the upper packer 5.
It is mixed with the chemical liquid 18 that circulates around the upper part of the liquid to dilute it and reduce the gelation time, or eliminate it altogether, and prevent the fixation of the chemical liquid injection tube 1 in the step-down process. Therefore, the chemical solution can be injected in each step sequentially while following the step-down process of a predetermined number of steps.

In this way, the chemical solution can be injected smoothly according to the setting.

It goes without saying that the embodiments of the invention of this application are not limited to the above-mentioned embodiments, and for example, various embodiments of the tube that are applicable to the step-up system can be adopted.

In addition, it is of course possible to change the design so that the packer has three or more stages.

It goes without saying that the applicable construction work is not limited to soft ground improvement, but can also be applied to other civil engineering construction projects.

<Effects of the Invention> As described above, according to the invention of this application, basically the strainer
In injection methods such as the double packer chemical injection method, the process of injecting chemical liquid into the ground from a strainer or the like by pressurizing the chemical liquid between the packers through expansion and contraction of the packers is, for example, a step-down method. In the process of expanding and contracting the packer during each step, the chemical solution that is pressurized between the packers flows around the shrinking packer, leaks into the upper and lower parts of the packer, and is filled, and gels over time. This facilitates smooth chemical injection without the risk of the chemical liquid injection tube being fixed and choked during the step stroke, such as the process of raising and lowering the chemical liquid injection tube, making it impossible to step up or step down. This is an excellent effect.

Therefore, the structure of the device used is extremely simple, as for example, the water absorption hose can be placed along the outer surface of the inner tube of the chemical liquid injection tube and facing the end of the packer, and its manufacturing and assembly is easy. It is easy to use and can be made with a low cost of 1 or more, and it also has the advantage of requiring little maintenance, inspection, maintenance, etc., is highly durable, and has good running properties.

[Brief explanation of drawings]

1 to 3 are explanatory diagrams of one embodiment of the invention of this application, in which FIG. 1 is a schematic partial cross-sectional view of a chemical liquid injection tube, and FIG.
FIG. 3 is a schematic sectional view of the chemical liquid injection process, FIG. 4 is a partially cutaway sectional view of a chemical liquid injection tube based on the prior art, and FIGS. 5 to 10 are schematic sectional views of the same chemical liquid injection process. 1'... Injection pipe, 5... Packer 14...
Ground, 16... Hole drilling, 18... Chemical solution,
21... Hose, 1'... Injection pipe, 14... Ground, 18... Chemical solution, 5... Packer 16... Hole drilling, 21... Hose, Fig.

Claims (4)

[Claims] (1) Inserting an injection pipe with multiple packers into a hole, expanding and contracting the packers at each step during the drilling, moving the injection pipe, and supplying chemical liquid between the packers by pressure into the ground. A method of injecting a chemical solution into a container, characterized in that water is supplied to the chemical solution leaking from the side of the packer when the packer is contracted to dilute it and prevent it from gelling. (2) The chemical liquid injection method according to claim 1, wherein the water is supplied through a hose provided along the side of the injection pipe. (3) The chemical liquid injection method according to claim 1, characterized in that the step is a down step. (4) Inserting an injection pipe with multiple packers into the drilling hole, expanding and contracting the packers step by step during the drilling process, moving the injection pipe, and supplying chemical liquid between the packers by pressure into the ground. In a chemical injection device that is used directly in a method of injecting chemical liquid into a container, a water supply hose with an opening facing at least one packer of an inner pipe having a plurality of packers is attached along the inner pipe. Characteristic drug injection device.