JP2553423B2 - Large diameter hard ground improvement device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for constructing a ground improvement body constructed mainly for the purpose of improving soft ground, foundations of building structures, and the like, and more particularly to a large-diameter and strong ground improvement body forming apparatus.

[0002]

2. Description of the Related Art Conventionally, a ground improvement method by spraying a curing agent has been developed through various trial and error. For example, the inventor of the present invention has invented or improved each construction method such as so-called single pipe , double pipe, and triple pipe, and as shown in FIG. We jointly developed a method of spraying a curing agent from the tip with other people. However, there are still unsolved parts in this method.
Was there. That is, the curing agent 53 is sprayed from the tip of the stirring blade 52.
By doing so, the curing agent is sprayed farther than in the conventional method.
Although it is possible to inject it, the position of the hardener injection port
The density of the curing agent is closer to the center of the improved body created from
There was a problem that the value became low. That is, as shown in FIG.
As described above, the intermediate portion 55b is stronger than the outer portion 55a.
Is smaller, and the central portion 55c is smaller than the intermediate portion 55b.
The strength is smaller, and in some cases donut shaped
It could have formed a good body. Therefore, the inventor
Application to solve the problem of
In the invention of 1), the injection nozzle is positioned at a position following the excavation blade.
I made a le. This allows blade excavation and high-pressure injection of hardener.
Repeat injection, high-pressure jet drilling, and agitation to insert the injection rod.
Because it can be pulled up, the curing agent can be wider and
It becomes possible to spread evenly, and various
It has become possible to create improved bodies according to geology and uses.

[0003]

However, in the above-mentioned simultaneous application, since the hardening agent injection nozzle follows the excavation blade in the rotational direction of the injection rod, the ground excavated once by the excavation blade is used. However, there is a possibility that the hardener may be unnecessarily excavated by the injection of the hardening agent, and depending on the geology, an improved body having a regular shape may not always be formed. Further, in the case of relatively hard ground, excavation precedes hardener injection, so excavation was not always reliable and easy. Therefore, in view of this drawback, the main object of the present invention is to easily create a more uniform and stronger hard ground improvement body having a large diameter that can be adapted to any geology and application.

[0004]

[Means for Solving the Problems] To achieve the above object
The ground improvement body construction apparatus according to the present invention is a hardening agent injection pipe.
Hardener that has a built-in and communicates with the hardener injection pipe
Injection nozzle, monitor, bit and rod longitudinal axis
Hardener injection rod with right angle overhanging drilling blade
In the ground improvement body forming apparatus including the
The injection direction of the rod is perpendicular to the longitudinal axis of the rod and
In the rotation direction of the injection rod with respect to the mounting position of
It is characterized by being preceded within a range of 45 degrees. Preferably, the excavation blade is configured to be expandable and contractible in the protruding direction.
It

[0005]

According to the present invention, the excavating blade is made to function as the excavating blade while maintaining the function as the stirring blade of the prior art, and the injection nozzle is within a range of about 45 degrees with respect to the excavating blade.
In because it is provided in the preceding position, first, the target ground
After softening and excavating by high-pressure injection of hardening agent,
Immediately after, it is possible to easily excavate by the excavating blade that follows , and more reliable and uniform ground improvement can be performed. Further, since the stirring blade has a structure capable of expanding and contracting, excavation can be carried out stepwise in a form that immediately adapts to various geological features and uses.

[0006]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 shows an embodiment according to the present invention. That is, the curing having the bit 16 and the monitor unit 17
In the agent injection rod 10, the excavation blade 14 that is firmly inserted and installed in the insertion portion 15 is installed above the monitor portion 17.
It is located so as to project in the direction perpendicular to the longitudinal axis of the head.
Further, according to the figure, the injection pipe 11 penetrating from the upper part of the injection rod 10 to the central part at a position located above the excavation blade 14 is shown.
And extends at the top of the drilling wing 14 for the injection pipe 11
Is bent and communicates with the injection nozzle 12. That is, since the injection nozzle 12 is provided on the side wall of the injection rod 10 , it is located above the excavation blade 14. However, the fact that the injection nozzle 12 is arranged above the excavation blade 14 is an ideal configuration in terms of firmly inserting the excavation blade 14 into the injection rod 10, but is not limited to this embodiment.
It may be installed at the same height as the excavation blade 14 or below the excavation blade 14. Either way
In the light, as shown in FIG.
The direction of injection is perpendicular to the longitudinal axis of the rod and
Approximately 45 degrees in the rotating direction of the injection rod 10 with respect to the attachment position
It is set to precede within the range of. That is, the vertical shaft is excavated with the bit 16, and first, the injection nozzle 1
The ultra-high pressure curing agent is sprayed onto the target ground from No. 2, and the ground is softened by containing water, and is pressurized and excavated by the spraying force. Then, after that, the ground is excavated uniformly by the excavation blades 14 by the rotation of the injection rod 10, so that the curing agent surely and uniformly spreads into the created void. Further, the excavation blade 14 is projected
Because it is a structure that can be expanded and contracted in the direction (the direction perpendicular to the rod longitudinal axis) . The excavation function corresponding to the target ground is demonstrated.
That is, the excavation wing 14 expands and contracts according to the target ground to be excavated in the same manner as the wing of an airplane has an expansion and contraction function according to the external atmospheric pressure, etc. It is possible to excavate and construct in stages. For example, in the hard ground, it is possible to achieve centralization of digging force by reducing the drilling blades 14, the drilling blade 1
It is possible to prevent damage to item 4 .

[0013]

According to the present invention, the target ground is first sprayed.
Softened and excavated by a hardener injected from a high pressure
Above, immediately after that , since excavation and stirring are performed by the excavating blade that follows within a range of about 45 degrees, it is possible to provide a ground improvement body having a large diameter, uniform and hard, quickly and reliably. In particular, this device has a wide application range and can be utilized for multipurpose ground improvement. That is, it is particularly effective for enhancing the foundation ground supporting force of a building, preventing ground subsidence, preventing cut soil, excavation slope slippage, and preventing displacement of the surrounding ground due to adjacent construction.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an embodiment of the present invention.

FIG. 2 is a schematic plan sectional view according to an embodiment of the present invention.

FIG. 3 is a schematic cross-sectional view showing a conventional example.

FIG. 4 is a ground improvement body according to a conventional example.

[Explanation of symbols]

10, 50 Injection rod 11, 51 Injection pipe 12 Injection nozzle 13, 53 Hardener 14 Excavation blade 15 Insertion portion 16 , 54 Bit 17 Monitor portion 52 Stirring blade 55 Ground improvement body

Claims (2)

(57) [Claims] 1. A hardener injection nozzle (12), a monitor section (17), and a bit (16) which incorporate a hardener injection pipe (11) and communicate with the hardener injection pipe (11).
In addition, the excavation wing (1
4) In a ground improvement body creating apparatus including a hardening agent injection rod (10), the injection direction of the injection nozzle (12) is a direction perpendicular to the rod longitudinal axis and the installation position of the excavation blade (14). A large-diameter hard ground improvement device for constructing a large-diameter hard ground, characterized by leading in the direction of rotation of the injection rod (10) within a range of approximately 45 degrees. 2. The excavation blade (14) extends in the projecting direction.
The large size according to claim 1, characterized in that the large size is provided.
Caliber hard ground improvement body construction device.