JPH0826539B2 - Ground improvement body construction method and its equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ground improvement method constructed mainly for the purpose of improving soft ground, foundations of building structures, etc., and particularly, for forming a large-diameter and hard ground improvement body. The present invention relates to an improved body construction method and its apparatus.

[0002]

Ground improvement method by injecting injecting a curing agent against BACKGROUND ART ground has evolved through various trial and error. The inventor of the present application has so far developed a conventional excavation blade or agitator.
Ground improvement device with stirring blades in addition to those without blades
In addition, we have also developed a ground improvement device that has an excavation blade that has an excavation function in addition to a stirring function and injects a hardening agent from the tip of the excavation blade. We have already applied for this series of prior art. Further, the inventors of the present application have also developed a method and an apparatus for rotating and injecting the hardening agent after providing a spiral groove on the inner wall of the hardening agent injection pipe extending to the excavation blade, and thereby, an extremely hard ground improvement body. We came to realize creation. As for the invention , July 26, 1991
The application has already been completed. In the final stage of these prior arts, particularly in the configuration disclosed in the above-mentioned application filed on July 26, in which the spiral groove is provided on the inner wall of the hardening agent injection pipe, the injection force of the hardening agent injected from the tip of the excavation blade is enhanced. The excellent effect was exhibited in the point that it was carried out and as a result that a tough ground improvement body was obtained.

[0003]

However, the inventor of the present application has conducted extensive research to realize a more reliable and tougher ground improvement technique than the above-mentioned preceding invention. Starting
Ming says that while maintaining economic efficiency and certainty,
Created a large-diameter and tough ground improvement body that goes one step further
The purpose is to do.

[0004]

The structure of a ground improvement body constructing apparatus according to the present invention for achieving the above-mentioned object has one or more hardening agent injection pipes and a pressurized gas injection pipe built therein, and In a ground improvement body constructing device having a monitor portion, a rod body excavating bit, and a hardening agent injecting rod having an excavating blade provided with an excavating blade bit at a lower part of the injecting rod main body portion, the pressurized gas injecting pipe is The injection pipes are concentrically arranged so as to surround the injection pipe, and both injection pipes communicate with the nozzle portion provided at the tip of the excavation blade, while spirals are provided in the injection pipe and the injection pipe. A groove is provided and the pitch of the spiral groove of the hardening agent injection pipe is made larger than that of the spiral groove of the pressurized gas injection pipe. In some cases, the curing agent injection pipe and the pressurization
Each of the spiral grooves in the gas injection tube is
Are provided so that the twisting directions of the are opposite to each other.
Further, the configuration of the ground improvement body construction method according to the present invention to achieve the above-mentioned object is to use a hardener injection rod having an excavation blade provided with an excavation blade bit in the lower portion, and to the tip of the excavation blade. A ground improvement body which forms a ground improvement body by injecting a hardening agent surrounded by a pressurized gas from the provided nozzle portion and gradually moving in the longitudinal axis direction while rotating the hardening agent injection rod. In the construction method, by providing spiral grooves in which the twisting directions are opposite to each other in the hardening agent injection pipe reaching the nozzle portion and in the pressurized gas injection pipe, respectively, the hardening agent and the pressurized gas that encapsulates the hardening agent are provided. It is characterized by injecting while giving rotations in opposite directions.

[0005]

In the ground improvement body forming apparatus, the hardener is incorporated into the pressurized gas by arranging the pressurized gas injection pipe concentrically so as to surround the hardener injection pipe and communicating with the nozzle portion. By injecting in this state, and further providing spiral grooves on the inner walls of both injection pipes, the curing agent and the pressurized gas are ejected while rotating. In addition, by making the pitch of the spiral groove of the hardener injection pipe larger than that of the pressurized gas injection pipe, it is possible to suppress the decrease of the speed of the hardener and effectively impart the rotational force. . Further, by making the twisting directions of both spiral grooves opposite to each other, the rotating directions of the curing agent and the pressurized gas at the time of injection become opposite to each other. In the ground improvement body construction method of the present invention, the stirring effect is increased by injecting the curing agent and the pressurized gas while applying rotations in opposite directions.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 (A) shows the ground improvement body construction according to the present invention.
It is a schematic sectional drawing which shows one Example of an apparatus. That is, curing
The agent injection rod 10 is provided with one hardening agent injection tube 11 and a pressurized gas injection tube 12 around the hardening agent injection tube 11, and a monitor section 18 and a rod body excavating bit 1 are provided.
9 and the hardener injection rod 10 has a digging blade 17 provided with a digging blade bit 20 below the rod 10 . Further, both injection pipes 11 and 12 communicate with the nozzles 15 and 16 provided at the tip of the excavation blade 17, respectively, and inside the excavation blade 17.
1 spiral groove for each inner wall of both injection tubes
3 and 14 are provided.

In FIG . 1A, a hardening agent for the excavation blade 17
The spiral groove 13 provided on the inner wall of the injection pipe 11 is
The spiral groove 14 formed on the inner wall of the body injection tube 12
Loosen the spiral by increasing the pitch of the
I'm quiet. This is a high-pressure injection into the curing agent injection pipe 11.
When the cured curing agent reaches the spiral groove 13,
Due to friction with the
To prevent fading, so that from the nuclear nozzle 15
This is to ensure efficient high-pressure injection of the curing agent.

Hardener injection pipe 11 and pressurized gas injection pipe 12
The threads of each of the
It may be provided in the opposite direction.

A hardener injection rod 1 having such a configuration
By using 0, the hardening agent to which the rotational force is applied by the spiral groove 13 is generated from the nuclear nozzle 15 provided at the tip of the excavation blade 17 and the pressurized gas to which the rotational force is applied by the spiral groove 14. The surrounding nozzles 16 concentrically surrounding the nuclear nozzle 15 respectively strongly inject the target ground. That is, since the hardener is injected in a form in which the surroundings are encapsulated by the pressurized gas, the hardener is injected into the ground more instantly and farther than in the case where the hardener alone is injected. And it can be done reliably over a wide range. The effect of incorporating the curing agent with the pressurized gas and the effect of imparting the rotational force only to the curing agent have been disclosed in detail in the preceding invention . Starting
In the case of Ming, the hardener is mixed with pressurized gas and hardened.
The spiral groove is used for both the agent and the pressurized gas.
Of the jetting force and excavating force
Better results can be achieved in both respects.

Incidentally, the injection of the pressurized gas can be performed simultaneously with the injection of the curing agent or with a time difference, and can be freely set according to the condition of the ground to be excavated or the excavation stage. Can be adjusted.

FIG. 1B shows the line A- in FIG.
FIG. 6 is a sectional view taken along line A ′. That is, in this embodiment
In the hardener injection rod 10 in
The hardening agent injection tube 11 and the pressurized gas injection tube 12 have a concentric structure in such a manner that the tube 12 surrounds the hardening agent injection tube 11 .
One this embodiment, Ru similarly der even drilling wing 17 parts both injection tube is communicated. Therefore, in addition to the hardener injection pipe 11,
The pressurized gas injection pipe 12 reaches the nuclear nozzle 15 and the peripheral nozzle 16 provided at the tip of the excavation blade 17 while maintaining the concentric structure even in the excavation blade 17 part .

As another embodiment (not shown), a pressurized gas injection tube may be provided beside the hardening agent injection tube.
It is also possible to provide a plurality of hardening agent injection pipes, and in this case, a pressurized gas injection pipe is provided around or beside each hardening agent injection pipe. Further, the respective spiral grooves 13 and 14 for rotating the hardener and the pressurized gas may be provided not only in the excavation blade 17 portion but also in the main body portion of the hardener injection rod 10 . In this case, cure
The hardening agent and the pressurized gas injected into the agent injection rod main body portion are vertical portions of both injection pipes before being pumped to the excavation blade 17.
It becomes and this is immediately rotated at.

FIG. 2 is a schematic perspective view showing an implementation situation of an embodiment according to the present invention. That is, one of the side ends of the excavation blade 17 provided in the lower portion of the hardener injection rod 10 is formed relatively thick and the other is formed relatively thin, and the excavation blade bit 20 is provided at the thinner side end. There is. And
Generally, the hardener injection rod 10 rotates in the direction having the excavation blade bit 20 (X direction) . By this, the digging
Blade blade 20 and tip of main body of hardening agent injection rod 10
The excavation bit 19 provided in the section advances to a predetermined depth while excavating the target ground. Then, at the stage of excavation to a predetermined depth, and injecting a curing agent 21 from the nucleus nozzle 15 provided at the distal end of the excavating blade 17 at ultra high pressure and while injecting a pressurized gas 22 from the surrounding nozzle 16 cured Agent injection
The rod 10 will be rotated and raised. That is, the curing agent
21 is given a rotational force by the spiral groove 13 (see FIG. 1) provided on the inner wall of the hardener injection pipe in the excavation blade 17 .
Then, similarly, a spiral provided on the inner wall of the pressurized gas injection pipe
The compressed air that has been given a rotational force by the groove 14 (see FIG. 1).
When wrapped in the body 22, do not rotate as indicated by arrow Y.
It will be injected in the Z direction. Hardener like this
21 and the pressurized gas 22 are both rotated and jetted,
In this case, as compared with the case where only the curing agent 21 is rotated and sprayed , the curing agent is forcibly filled in a wider range more reliably. Of course, the curing agent injection pipe 11 and the pressurized gas injection pipe 12
In the structure in which the screw threads are provided in opposite directions in the spiral grooves 13 and 14, respectively , the hardener 21 and the hardener 21 are added.
Injects in the Z direction while rotating with the pressurized gas 22 in opposite directions
Will be done. Reverse curing agent 21 and pressurized gas 22
When rotated in the opposite direction, the stirring effect increases and
It has the effect of stabilizing the injection direction.

[0014]

According to the present invention, the rotational injection of both the curing agent and the pressurized gas and the so-called lift effect due to the encapsulation of the curing agent by the pressurized gas are combined with each other to further advance the prior art and make it more robust. You can instantly and reliably create a high quality ground improvement body. Especially, the spiral groove in the hardener injection pipe
By slowing down the pitch of the
It is excellent to prevent unexpected deceleration
The effect is obtained.

[Brief description of drawings]

[FIG. 1 (A)] One embodiment of a ground improvement body construction apparatus according to the present invention
It is a schematic sectional drawing which shows an example.

1B is a cross-sectional view taken along the line AA ′ in FIG.

FIG. 2 shows the state of implementation of the ground improvement body construction method according to the present invention .
It is a schematic perspective view shown.

[Explanation of symbols]

 10 Curing Agent Injection Rod 11 Curing Agent Injection Tube 12 Pressurized Gas Injection Tube 13 Spiral Groove of Curing Agent Injection Tube 14 Spiral Groove of Pressurized Gas Injection Tube 15 Nuclear Nozzle 16 Surrounding Nozzle 17 Drilling Blade 18 Monitor Part 19 Rod Body Excavation Rod 20 Drilling blade bit 21 Hardener 22 Pressurized gas

Claims (3)

[Claims] 1. A monitor part (18), a rod body excavating bit (19), and an injection rod body, which incorporates one or more curing agent injection pipes (11) and a pressurized gas injection pipe (12). Hardener injection rod (10) having a drilling blade (17) with a drilling blade bit (20) in the lower part of the section
In the ground improvement body creating apparatus, the pressurized gas injection pipe (12) is connected to the hardening agent injection pipe (1).
Nozzle part (1 ) in which both injection pipes are arranged concentrically so as to surround (1 ) and provided at the tip of the excavation blade (17).
6, 15) while the curing agent injection pipe (1
Provided with a spiral groove (13, 14) respectively in 1) and within the pressurized gas injection tube (12), wherein the pressurized gas injection tube spiral groove (13) of the curing agent injection pipe (11) ( 12) A ground improvement body constructing device having a pitch larger than that of the spiral groove (14) . 2. The spiral groove in each of the hardening agent injection pipe (11) and the pressurized gas injection pipe (12) .
The ground improvement body constructing apparatus according to claim 1, wherein (13, 14) are provided such that their twisting directions are opposite to each other. 3. A nozzle part provided at the tip of the excavation blade (17) using a hardener injection rod (10) having an excavation blade (17) having a excavation blade bit (20) in the lower part.
A ground improvement body is created by injecting a hardener surrounded by a pressurized gas from (15, 16) and gradually moving the hardener injection rod (10) in the longitudinal axis direction while rotating the hardener injection rod (10). In the ground improvement body construction method, the hardening agent injection pipe (1 ) reaching the nozzle part (15, 16) is used.
1) By providing spiral grooves (13, 14) in opposite twist directions inside the pressurized gas injection pipe (12), the curing agent and the pressurized gas that encapsulates the curing agent are provided.
A method for constructing a ground improvement body, which comprises injecting and while rotating in opposite directions.