JPH086308B2 - Deformation ground improvement body construction method - 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 body construction method which is constructed for the purpose of improving soft ground, building structure foundation, etc., and particularly, depending on the conditions of the ground and the use of the ground improvement body. The present invention relates to a construction method capable of producing various deformed ground improvement bodies.

[0002]

2. Description of the Related Art Conventionally, various ground improvement methods have been invented as hardening methods for soft ground. In particular, the emphasis was placed on how to efficiently create a ground improvement body. For example, there are various construction methods such as so-called single pipe, double pipe, and triple pipe by the present inventors. These improvements, including those of other inventors, are new methods that are reasonably good only for those that have been developed through various trials and errors. However, recently, unsolved parts have been exposed due to the heightening of buildings and the increase of deep underground structures. That is, in the conventional method, only the curing agent was sprayed from the lower side wall of the boring rod, but this was not able to meet the requirements of high-rise and large-depth structures. This is because if the structures, etc., become high-rise, of course, it will be necessary for soft ground, and even in an earthquake country such as Japan, it will be necessary to construct a hard ground improvement body more than before.

[0003]

[SUMMARY OF THE INVENTION Therefore, the present inventors have Oite the tough soil improvement material reclamation equipment of the present concurrently herewith, by also providing the injection nozzle at the lower end portion of the rod, recent ground improvement It has come to provide a tough and improved body suitable for body use. However, the present invention is an improved invention in a so-called single pipe, which enhances the performance of the single pipe and provides an epoch-making and tough improved body which is not present in the conventional improved body, but nevertheless, in the recent applications. It's a perfect fit, not a multifaceted improvement. Therefore, an object of the present invention is to provide a construction method for forming a modified ground improvement body which can respond to the recent demands for ground improvement body construction work in various fields.

[0004]

Means for Solving the Problems] was to achieve the above object
The method for constructing a modified ground improvement body according to the present invention is
A plurality of hardener injection nozzles on the side wall and tip of the rod
Nozzles and the amount of spray from each nozzle
Control valve, as well as automatic or
Hardening using a ground improvement body building device with a manual control device
In the process of spraying the agent, the conditions of the ground or the use of ground improvement
Injection amount, injection time, or injection angle of each nozzle depending on the way
To control the deformation of the ground
It is characterized by forming a good body.

[0005]

[Function] Appropriate injection amount, injection time, and injection angle of each nozzle
By controlling, the curing agent injection changes depending on the location.
And the resulting ground improvement body is not just a bar
Instead, it becomes a deformed ground improvement body having a protrusion on the middle side.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. First, FIG. 2 shows a box used in the construction method according to the present invention.
FIG. 3 shows a cross-sectional view of the tip of an example of a ring rod. This fruit
The device of the embodiment uses a so-called double tube,
In the boring rod 8 some hardening along its longitudinal axis
An agent injection pipe 10 and an air injection pipe 12 are provided. baud
The side wall and the tip of the ring rod 8 are hardened respectively.
Side jet nozzle 13 and direct jet nozzle which are agent jet ports
15 is provided, and both nozzles 13 and 15 are cured respectively.
It communicates with the agent injection pipe 10. In addition, the side injection nozzle
An air injection nozzle 14 is formed around the outer circumference of
The air injection nozzle 14 is connected to the air injection pipe 12.
Through. Side jet nozzle 13 and direct jet nozzle
15 has injection control valves 16 and 17, respectively,
These control valves 16 and 17 are used to control each nozzle including injection stop.
So that the injection amount injected from
Has become. Opening / closing control of these control valves 16 and 17
Control is performed manually or automatically by a controller (not shown).
Be done. Furthermore, a bit is provided at the lower end of the boring rod 8.
A propulsion force sensor 18 and a rod rotation torque sensor 19 are installed.
Is installed and a bit (excavation tooth) 34 is provided protruding downward.
Has been.

The side jet nozzle 13 is replaced with the air jet nozzle 1
4 and the hardener and high
By injecting compressed air, the curing agent is wrapped in high pressure air.
It is sprayed in the enclosed state, so that the curing agent and the surrounding
Friction resistance is reduced and high-pressure injection becomes possible. Directly below
The die injection nozzle 15 is provided with a nozzle that embeds it
The reason is that since the direct injection nozzle 15 is located directly below the injection pipe 10, the injection pressure is generally higher than that of the side injection nozzle 13, and the injection hole which is a vertical hole has already been excavated by the boring rod 8. This is because, compared with the side surface of the rod, high pressure injection is not usually required. That is, when the ground improvement body with a large diameter is required because there is only a vertical hole and the side surface is not excavated,
It is more suitable for side surface excavation to narrow down the control valve 17 of the direct type injection nozzle 15 as much as possible, and to inject high-pressure air from the air injection nozzle 14 to inject the hardener from the side surface type injection nozzle 13 in a combined state. Because it is.

According to the method of the present invention, the ground condition or ground improvement
Depending on the use of the body, the lateral injection nozzle 13 and the direct injection nozzle
The injection amount, injection time, or injection angle of the cheat 15 is appropriately controlled.
Deformation ground modification according to conditions and applications by trawling
Form a good body. For example, control of the side jet nozzle 13
Close the valve 16 and apply the curing agent only from the direct injection nozzle 15.
Make it jet. In this case, pull the boring rod 8 gradually
By raising , the curing agent is injected only into the injection hole which is a vertical hole, and only the so-called rod-shaped ground improvement body 32 (see FIGS. 4 and 5) is formed. Further, even when the control valve 16 of the side surface type injection nozzle 13 is closed, it is possible to operate only the air injection pipe 12 which is an independent injection pipe, and although it has not been carried out in the past, only air is injected. By injecting, the diameter of the rod-shaped improvement body can be increased. In this case, it goes without saying that by opening not only the air injection nozzle 14 but also the side surface injection nozzle 13, it is possible to create an improved body having a larger diameter than in the case where only the air injection nozzle 14 is opened. The case where the control valve 17 of the direct injection nozzle 15 is closed and only the side injection nozzle 13 is opened to inject the curing agent is as in the conventional technique.

Next, the direct injection nozzle 15 is opened to set the curing agent.
While spraying, rotating the boring rod 8 gradually
In the process of raising next, in the process of rotating the boring rod 8.
If it is within the specified rotation angle range (eg 30 degrees)
Open the control valve 16 of the side injection nozzle 13 only
Intermittent injection while the boring rod 8 rises a predetermined distance
After that, the control valve 16 of the side surface injection nozzle 13 is opened.
Instead, the boring rod 8 is raised by a predetermined distance. So
By repeating this, the deformed ground improvement body 31 having the branch-like ground improvement body 33 formed only in one direction around the rod-shaped ground improvement body 32 can be created (see FIG. 4 (A)). A plan sectional view of this improved body can be understood in FIG. 5 (1).

Further, by operating the control equipment cured, while rotating the boring rod 8, when injecting the curing agent from the side mold injection nozzle 13 and direct-injection nozzle 15, at a fixed angle from the side-type injection nozzle 13 Not only by injecting the agent, but by vertically and intermittently repeating the injection, the rod-shaped ground improvement body 3 as shown in FIG.
The modified ground improvement body 31 in which the branch-like ground improvement bodies 33 are alternately formed in 2 can also be formed. If the operation for creating such a branch-like ground improvement body 33 is performed at the same position in the vertical relationship, the deformed ground improvement body 31 as shown in FIG. 5B can be created.

In addition, the boring rod 8 rises excessively.
Then, the injection of the curing agent from the side surface injection nozzle 13 is intermittently performed.
If you go to, together with the so-called direct injection type construction,
A modified ground improvement body 31 as shown in FIG. 4C can be created. This improved body is generally the strongest and can cope with various types of ground centered on soft ground. A plan view of this improved structure is as shown in FIG.

[0012] In more various operations, through the control valve 17 a direct-type injection nozzle 15, but it is of course possible to thus controlled by the control equipment on the ground of the control center, in particular, the side-type injection nozzle 13 Control valve 16
The significance of controlling by the control device is great. Then, the control by this control device can generally be automatically controlled by selecting a pre-programmed spray pattern on the touch panel according to the soil condition. Needless to say, each injection pattern can be controlled manually.

FIG . 3 is a boring used in the construction method according to the present invention.
The sectional view of the front-end | tip part of the other example of a grod is shown. This example
Is a so-called triple tube technology (Japanese Patent Application No. 1-3077).
No. 4, U.S. Pat. No. 4,971,480)
It is. In this example, the direct injection nozzle 15 is used for injection.
The hardener injection pipe 11 for
It is provided independently of the agent injection pipe 10. Therefore, both
The injection pressure of slur can be controlled independently without being affected by each other.
In particular, various controls corresponding to the various types of modified ground improvement bodies described in the first embodiment described above become extremely easy.

In addition, if one curing agent injection pipe is used for both the side surface type injection nozzle 13 and the direct type injection nozzle 15, the amount of the curing agent injected will be reduced by the amount that is absorbed by the other side. In the case of this example, as shown in FIG.
And the individually provided ultra high pressure grout pumps 20 and 21.
Since the hardening agent pressure-fed from is injected through the individual injection pipes 10 and 11, it is possible to inject a sufficient hardening agent if necessary. Therefore, it is possible to create a deformed ground improvement body as desired. For other configurations, please refer to the above
Since it is similar to the embodiment, the same reference numerals are given and redundant description is given.
Is omitted.

FIG . 1 shows the use of the boring rod shown in FIG.
It is the whole schematic structure figure showing an example. As shown in Figure 1,
Air compressor 22, two super high pressure grout pump 2
0,21 or al, air and curing agent, respectively is pumped,
Each injection nozzle 14, 23, 24, each injection nozzle 14, via an independent injection pipe of the boring rod 8.
It reached to 13 and 15, the total control unit 29 of the ground, in accordance with the commanded injection pattern, so that the curing agent is injected. Further, in the figure, 9 is an analyzer, 26 is an oyster.
Pump, 27 is an oil tank, 28 is a rotary thrust reverser
Reference numeral 30 is a motor. In addition, the boring rod 8
Regardless of whether or not the curing agent is sprayed under control, the rotation speed always rises at a constant speed. However, it is also possible to rotate only a certain angle by the control device 29. By the above operations, various deformed ground improvement bodies including those not shown can be constructed.

[0016]

As described above, according to the present invention,
Injecting each nozzle according to the conditions of the ground or the application of the ground improvement body
It controls the injection amount, injection time, or injection angle, and
To form a modified ground improvement body according to the application.
Therefore, it is tough and useful for the soil conditions of the target ground.
A ground improvement body can be obtained. In particular, FIG.
Deformation with protrusions on the side as shown in (B) and (C)
The ground improvement body can cope with soft ground and the like more than the conventional mere rod-shaped ground improvement body . Further, the rod-like soil improvement material by straight lower mold injection nozzle that Do as mighty than the conventional. In view of the increase in the number of buildings and the increase in deep underground structures, the need for the modified ground improvement body according to the present invention is increasing.

[Brief description of drawings]

FIG. 1 is an overall schematic configuration of an apparatus used in a construction method according to the present invention .
It is a figure .

FIG. 2 shows a boring rod used in the construction method according to the present invention .
It is sectional drawing of the tip part of an example .

FIG. 3 shows a boring rod used in the construction method according to the present invention .
It is sectional drawing of the front-end | tip part of another example .

4 is a longitudinal sectional view of a modified soil improvement material, which is reclamation by method according to the present invention.

5 is a transverse sectional view of a modified soil improvement material, which is reclamation by method according to the present invention.

[Explanation of symbols]

 8 Boring rod 9 Analyzing device 10, 11 Hardener injection pipe 12 Air injection pipe 13 Side injection nozzle 14 Air injection nozzle 15 Direct injection nozzle 16, 17 Control valve 18 Bit propulsion force sensor 19 Rod rotation torque sensor 20, 21 Super High-pressure grout pump 22 Air compressor 23, 24 Curing agent inlet 25 Air inlet 26 Oil pump 27 Oil tank 28 Rotation propulsion / retraction mechanism 29 Controller 30 Motor 31 Deformed ground improvement 32 Rod-like ground improvement 33 Branch-like ground improvement 34 bit

Claims (2)

[Claims] 1. A tip side wall portion of a boring rod, a plurality of nozzles serving as a hardening agent jet port at the tip portion, a control valve for controlling an injection amount ejected from the nozzle, and an automatic or manual control device for controlling the control valve. In the process of injecting the curing agent, using the ground improvement body creating apparatus having, the injection amount, injection time, or injection angle of each nozzle is controlled according to the conditions of the ground or the use of the ground improvement body, and thus according to the application. Deformed land
A method for constructing a modified ground improvement body, which comprises forming a ground improvement body. 2. The method for constructing a modified ground improvement body according to claim 1, wherein the formed ones are various kinds of modified ground improvement bodies.