JP2003020637A - Agitating pile construction method and agitating pile construction equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an agitating pile construction method and agitating pile construction equipment capable of forming an improved body aslant from the side of the equipment even when a structure and railway equipment are present near the surface of the reinforced portion of the ground. SOLUTION: In this agitating pile construction method for forming a columnar improved body, a rod 55 having agitating blades 53 and 54 is rotatingly intruded into a soft ground 50, and solidifying material 52 discharged from near the tip of the rod 55 and loosened soil around the rod 55 are mechanically agitated by the agitating blades 53 and 54. The improved body is formed aslant relative to the vertical direction of the improved body.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stirring pile construction method and a stirring pile construction apparatus, and more particularly to a stirring pile construction method suitable when a structure or railway equipment exists near the ground above the ground to be improved. And a stirring pile construction device.

[0002]

2. Description of the Related Art When constructing a building such as a tunnel in soft ground, it may be necessary to enhance or strengthen the water stopping capability in advance for a predetermined deep portion of the surrounding ground. As a method for improving such soft ground, there are an injection method and a high-pressure jet stirring method.

On the other hand, one of the methods for strengthening the ground entirely from near the ground for a relatively wide range is to penetrate the ground while rotating a rod equipped with stirring blades, and to tip the tip of the rod. There is a so-called mechanical stirring pile construction method in which a solidified material and loose soil around the rod are stirred with a stirring blade while discharging the solidified material at a low pressure from the vicinity, thereby forming a pillar (pile) -shaped improved body.

The second method is a combined method of using the mechanical stirring pile construction method described above and the injection stirring for injecting the solidified material at high pressure from the vicinity of the tips of the stirring blades. In this combined construction method, by adding the improver by injection stirring to the outside of the improver by mechanical stirring, it is possible to increase the diameter of the improver and thus improve the construction efficiency, Since the part can be wrapped, the improvement body can be integrated.

Conventionally, both the mechanical stirring pile construction method and the combined construction method of the mechanical stirring and the jet stirring have been based on the premise that the columnar improved body is formed in a substantially vertical direction.

[0006]

However, since the conventional mechanical stirring pile method is premised on the construction in the vertical direction, there is a structure or railway facility near the ground for the reason described below. , It was not used for ground improvement for the lower layers.

That is, when a structure or a railway facility exists near the ground to be improved and the improved body is to be formed by the mechanical stirring pile method, the rod must be inserted obliquely. The vertical component of the rod is reduced to cause insufficient penetration force, and the rod that penetrates the ground becomes slanted, which deteriorates the stability of the base machine and the accuracy of the penetration angle of the rod. The problem occurs.

Further, as the construction length becomes longer, the weight of the rod becomes heavier and the rigidity of the rod becomes lower, so that the tip end of the rod tends to bend downward on soft ground, impairing the straightness of the penetration. Occurs.

Further, in the case of the jet agitation combined use type, the solidifying material is jetted from the tip of the agitating blade at a high pressure in a direction perpendicular to the axis of the rod, so that the rod is opposite to the jetting direction due to the influence of the jetting force. There is a tendency to bend to the side, and the straightness of the penetration is particularly impaired.

As described above, in the mechanical stirring pile construction method, it is said that there are some problems in diagonal construction.
Conventionally, although the rod may be tilted within a range of about 5 degrees with respect to the vertical direction for fine adjustment during transportation or construction, it has been put to practical use as a method for positively forming an improved body in an oblique direction. It didn't come.

Therefore, when there is a structure or a railway facility near the ground, the ground improvement for the lower layer has been carried out by an injection method or a jet agitation method that does not use compressed air.

[0012] However, in the pouring method, there is a strong tendency for split pouring in cohesive ground, uniform improvement cannot be expected, and there is a high possibility that ground uplift will occur, so there is a structure above or above ground. There was a possibility that this would have a considerable impact.

Also in the case of the jet agitation method, the method of directly injecting the solidifying material (without using compressed air) is premised on that the excavated soil is not actively discharged, and only a small amount of earth and sand is discharged. Since it is not discharged, there is a high possibility that the solidified material will cause ground upheaval.
Since the improvement body per book is small, there is a problem that construction efficiency is poor and it is economically disadvantageous. In addition, in the method of using compressed air together, there is a fatal problem that when the diagonal construction is performed, an air pool is left in the ground and an unimproved portion is generated.

Therefore, it is advantageous if the improved body can be formed in the oblique direction by a mechanical stirring method that does not cause problems such as ground uplift and air trapping, like the injection method and the jet stirring method.

The object of the present invention is to solve such problems, and even if there is a structure or railway equipment near the ground to be improved, the side of these equipment can be used. A technical object is to provide a stirring pile construction method and a stirring pile construction device capable of forming an improved body in an obliquely downward direction.

[0016]

The present invention is a stirring pile construction method and a stirring pile construction device, and is configured as follows to solve the above-mentioned technical problems. That is, the present invention is
A solidifying material that penetrates while rotating a rod equipped with a stirring blade in soft ground, and is discharged from near the tip of the rod,
In the stirring pile method of forming a columnar improved body by mechanically stirring loose soil around the rod with the stirring blade, forming the improved body in an oblique direction with respect to the vertical direction. Characterize.

Examples of the solidifying material include cement-based solidifying material. This solidifying material and water are kneaded at an appropriate ratio to produce a slurry, which can be discharged at a low pressure from a discharge port near the tip of the rod.

According to the stirring pile construction method of the present invention, mechanically,
That is, by directly stirring with a stirring blade without using high-pressure injection, an improved body can be formed in an oblique direction with respect to the vertical direction, so even if there is a structure or railway equipment near the ground above the ground to be improved, The improvement body can be formed obliquely by inserting the rod obliquely from the side of these facilities toward the portion to be improved.

Further, since the straightness of the rod is impaired when the length of construction of the improved body becomes long, the straightness of the rod is maintained by the straightness maintaining means in the present invention.

As the straight-moving holding means, an outer cylinder having a diameter substantially the same as the diameter of the portion scraped by the stirring blade in the ground,
The structure of the inner cylinder fitted to the rod and the connecting plate for connecting the inner cylinder and the outer cylinder can be exemplified.

Here, as the outer cylinder, one having a circular or polygonal cross section can be exemplified, but since the portion to be shaved by the stirring blade has a substantially circular cross section, the outer cylinder also has a circular cross section. preferable.

Further, in the present invention, in order to improve the construction efficiency of the improved body and at the same time to integrate the adjacent improved bodies, in addition to mechanical stirring by a stirring blade, injection stirring for high pressure injection of the solidifying material is used together. did. As this injection stirring method, a method of injecting the solidified material at a high pressure from the tip of the stirring blade can be exemplified.

As described above, the combined use of the injection and stirring forms the improved body formed by the agitation by the high-pressure injection of the solidifying material on the outside of the improved body formed by the mechanical stirring by the stirring blade. Since the diameter of the body is enlarged, the construction efficiency is improved. Further, the portions formed by the jet agitation of the adjacent improvement bodies can be lapped, whereby the improvement bodies can be integrated.

When the injection stirring is used in combination, a lateral force acts on the rod, which tends to cause lateral displacement.
In the present invention, the rod is extended from the tip in the penetrating direction and the tip is provided with a pilot bit, and the pilot bit is pierced into the ground to prevent lateral displacement.

Further, in this mechanical stirring pile construction method or the construction method in which spray stirring is used in combination with this, the amount of solidifying material per amount of improved soil is about half that of the spray stirring construction method, and ground uplift is minimized. Can be stopped.

In order to carry out the above-mentioned stirring pile construction method, the stirring pile construction device of the present invention is a rod for penetrating into soft ground, a stirring blade attached to the rod, and a solidifying material from near the tip of the rod. For discharging solidification material, a rod chuck for slidably and chuckably supporting the rod, a rotation driving means for rotating the rod, and a rotation driving means for fixing the rod chuck. A slide table for slidably holding the slide table, a slide means for sliding the rotation driving means for penetrating the rod, and an inclination angle of the slide table for the vertical direction in order to adjust the penetration angle of the rod with respect to the vertical direction. Adjusting means for adjusting the solidifying material and loose soil around the rod by the stirring blade. In a stirring pile construction device that forms a columnar improved body in the soft ground by mechanically stirring, when the rod is obliquely penetrated at a predetermined angle with respect to the vertical direction, the straightness of the rod is improved. It is characterized in that the improved body is formed obliquely with respect to the vertical direction by having a straight-moving holding means for holding the improved body.

In order to prevent the rods from colliding with equipment near the ground at the portion to be improved, the rods should be divided into a plurality of pieces with a predetermined length, and each rod should be connected when it penetrates into the ground. it can.

An example of the solidified material discharge means is a discharge port of an appropriate size provided at the tip of the rod. In this case, the rod is hollow, the internal space is connected to the discharge port, and the solidifying material is supplied to the internal space to discharge from the discharge port.

The rotation drive means for rotating the rod can be exemplified by a power swivel, and the slide means can be exemplified by a hydraulic cylinder. Further, the angle adjusting means tilts the slide table around the rotation axis by a predetermined angle,
A raise cylinder for pressing or pulling one end of the slide table can be exemplified.

By tilting the slide table by the angle adjusting means, the penetration angle of the rod with respect to the vertical direction is 5 ° to 80 °, preferably 10 ° to 60 °.
It can be adjusted in the range of.

In this stirring pile construction device, since the improved body can be formed obliquely with respect to the vertical direction, even when there is a structure or railway equipment near the ground above the ground to be improved, it is possible to avoid such equipment from the position. The improved body can be formed obliquely toward the target place.

Moreover, since the straightness of the rod can be held by the straightness holding means, the improved body can be formed in a correct position and in a correct shape.

Further, in this stirring pile construction device, one or a plurality of injection means for injecting the solidified material into the stirring blade at a high pressure in a direction substantially perpendicular to the central axis of the rod can be provided. , Mechanical stirring and jet stirring can be used together.

Further, in order to prevent the rod from being displaced laterally due to high-pressure injection of the solidifying material, a pilot bit extending from the tip of the rod in the penetrating direction and having a sharp tip is provided. I stabbed in the ground.

[0035]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of a stirring pile construction method and a stirring pile construction apparatus according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a view showing a stirring pile construction device 5 of the present invention. The stirring pile construction device 5 forms an oblique improvement body on the soft ground 50, and has a rod 55 for penetrating the soft ground 50, and stirring blades 53, 54 attached to the tip end portions of the rod 55. And a discharge port 98 which is a solidified material discharge means for discharging the solidified material 52 (see FIG. 12) from the vicinity of the tip of the rod 55.

Further, this stirring pile construction device 5 is composed of the rod 5
5, a rod chuck 74 that supports the movable member 5 in the longitudinal direction so as to be movable and chuckable, a power swivel 57 that is a rotation driving unit that rotates the rod 55, and a rod swivel 57 that is slidable while fixing the rod chuck 74. The slide table 56 held on the ground and the power swivel 57 for inserting the rod 55 into the ground 50.
Hydraulic cylinder 5 as sliding means for sliding
8 and a vehicle body 60 with a crawler for moving the entire apparatus
It has and.

Further, this stirring pile construction device 5 is constructed by the rod 5
5 for adjusting the penetration angle α with respect to the vertical direction within the range of 5 ° to 80 °, preferably within the range of 10 ° to 60 °, an adjusting means 72 for adjusting the inclination angle of the slide table 56 with respect to the vertical direction, In order to maintain the straightness of the rod 55 when it penetrates, the straightness holding means 80 attached to the rod 55 is provided.

As a result, the stirring pile construction device 5 penetrates the rod 55 obliquely with respect to the vertical direction at a predetermined angle α,
Soil cement 96 (FIG. 14), which is a columnar improvement, can be formed obliquely with respect to the vertical direction.

Next, each component described above will be described. The ground 50 is a soft ground mainly composed of silt or cohesive soil, and is easily loosened by the rotation of the stirring blades 53 and 54 and the high-pressure injection of the solidifying material 12. At a certain depth from the ground in the penetration portion of the rod 55, the stirring blade 5
A small diameter section 61 that is agitated only by 3, 54,
Behind that is the large diameter section 62 enlarged by the high pressure injection of the solidifying material 52.

The rod 55 is a first rod 55 having a relatively short length so as not to come into contact with overhead equipment such as overhead wires.
It is divided into a to nth rod 55n. When the rod 55 penetrates into the ground 50, the first rod 5
Penetrate while sequentially joining from 5a. Stirring blade 5
Examples of 3, 54 are as shown in FIG.

A plurality of cutters 63 are attached to the lower stirring blade 53, and the cutter 50 excavates the ground 50. Further, a discharge port 98 for discharging the solidified material 52 at a low pressure is provided in a portion of the first rod 55a below the stirring blade 53. Further, an injection nozzle 59 for injecting the solidified material 52 at high pressure is provided at the tip of the stirring blade 53. This injection nozzle 59
Can be provided on all of the stirring blades 53, but may be provided only on a part of them depending on the usage conditions.

The first rod 55a is hollow, and a thin tube 65 for supplying the solidifying material 52 to the injection nozzle 59 is inserted inside the first rod 55a. The thin tube 65 is provided with the stirring blade 53.
It is connected to the injection nozzle 59 via the communication passage 64. A joint 70 is provided at the tip of the thin tube 65.
The space outside the thin tube 65 is connected to the discharge port 98. The solidifying material 52 is supplied to the discharge port 98 through this space.

As the solidifying material 52, a cement-based solidifying material,
For example, Hardkeep P-530 (trade name) can be used. The cement-based solidifying material 52 and water are kneaded at a ratio of 8:10 to generate a slurry, which is discharged at a low pressure from the discharge port 98 and is also discharged at a high pressure from the spray nozzle 59.

As shown in FIG. 2, a pilot bit 66, which extends in the penetrating direction of the first rod 55a and has a sharp tip, is attached to the tip of the first rod 55a. By piercing the pilot bit 66 into the soil, the first rod 55a is displaced laterally even when the solidified material 52 is injected from the injection nozzle 59 in the diametrical direction with respect to the central axis of the first rod 55a. Can be prevented. The other end of the first rod 55a has a second
A joint protrusion 67 is provided to connect the rod 55b.

Of the rods 55 in FIG. 1, the first rod 55
The second rod 55b to the nth rod 55n except a have the same structure as shown in FIG. That is, the second rod 55b to the nth rod 55n are hollow, and the joint recess 68 and the joint protrusion 67 that can be fitted into the joint recess 68 are provided at both ends thereof. Further, in the inner space of the second rod 55b to the nth rod 55n, a thin tube 69 is provided.
Has been inserted. At both ends of this thin tube 69, a joint 7
0, 71 are provided.

As shown in FIG. 4, the slide table 56 of FIG. 1 is rotatably attached to a vehicle body 60 with a crawler via a rotary shaft 75. This slide table 5
A rod chuck 74 is fixed on the shaft 6, and a power swivel 57 is slidably mounted on the shaft 6. The support member 7 is attached to the tip of the slide table 56.
3 is attached.

Rod 5 connected to power swivel 57
5 is rotatably and slidably supported by a rod chuck 74. Further, when the rod 55 is joined or divided, the rod chuck 74 holds the rod 55 to stop the rotation of the rod 55.

As shown in FIG. 4, the adjusting means 72 has a crawler-equipped vehicle body 60 for holding the slide table 56.
And a raise cylinder (hydraulic cylinder) 77 attached to the crawler-equipped vehicle body 60 for rotating the bracket 76. The above-mentioned hydraulic cylinder 58 is attached to the lower surface side of the bracket 76.

The adjusting means 72 includes a raise cylinder 77.
By expanding and contracting, as shown in FIGS.
The inclination angle α of the slide table 56 with respect to the vertical direction is 0 ° (FIG. 5) to 80 °, preferably 10 ° to 60.
It can be adjusted in the range of ° (Fig. 6). Note that FIG.
Shows a state when the stirring pile construction device 5 is moved, and reference numeral 94 in FIG. 6 is a lock lever for locking the slide table 56.

As shown in FIGS. 4 and 5, the highest portion of the stirring pile construction device 5, that is, the slide table 56.
The height of the upper end of the is set to a predetermined height H2 or less so as not to collide with, for example, an overhead line at the construction site.

That is, at the time of constructing the stirring pile, as shown in FIG. 4, the inclination angle of the slide table 56 is set to α °, and the height of the upper end portion thereof is H1 (H1 <H2) or less. Further, as shown in FIG.
When the inclination angle of is 0 degree, the height of its upper end is H2.
It is set as follows. In this embodiment,
H1 = 3 m and H2 = 4 m are set.

The straightness maintaining means 80 of FIG.
Is attached at an appropriate position, in the present embodiment, to the intermediate portion and the upper side of the rod 55. This straightness maintaining means 80
Is the inner cylinder 8 fitted to the rod 55, as shown in FIG.
1, an outer cylinder 82 concentric with the inner cylinder 81, and a plurality of coupling plates 83 that couple these inner and outer cylinders 81, 82.

As shown in FIG. 8, the straight-moving holding means 80 is divided into two semicircular portions 81a, 81b, 82a, 82b at a cut surface passing through the diameters of the inner and outer cylinders 81, 82.
Then, one cut portion of the outer cylinder 81 is joined by a hinge 84, and the other cut portion is detachably joined by a lock member 85.

On the other hand, the rod 55 is provided with a small diameter portion 86 at a predetermined position, and the straightness maintaining means 8 is attached to the small diameter portion 86.
The rectilinear holding means 80 can be attached by rotatably fitting the 0 inner cylinder 82. The rod 55 rotates while the rod 55 penetrates, but the rectilinear holding means 80 does not rotate because the resistance of the soil acting on the coupling plate 83 is large.

The straightness maintaining means 80 has an outer cylinder 82.
Since it is supported all around by the relatively hard soil outside the loose soil, it will not be displaced laterally. Therefore, even if the solidified material 52 is injected at high pressure from the injection nozzle 59 of the stirring blade 53, the rod 5 located at the center of the outer cylinder 82.
It is possible to reliably prevent the position 5 from being displaced laterally.

In the above-described embodiment, the outer cylinder 82 of the straight-movement holding means 80 has a perfect cylindrical shape, but the outer cylinder 82 has
As shown in FIGS. 9A to 9C, a relatively large opening 8 is formed.
2a, an elongated opening 82b, a small round hole 82b, etc. may be provided.

Further, in the above embodiment, the stirring blade 5
Since the cross section of the portion excavated by 3, 54 is substantially circular, the outer cylinder 82 also has a circular cross section, but the cross section of the outer cylinder 82 may be polygonal.

As shown in FIG. 4, the vehicle body 60 with crawlers in FIG. 1 has a driver's seat 90, a control section 91, and crawlers 92.
And a solidifying material supply device 97. An extendable support column 93 is attached to the rear end of the control unit 91 to receive a reaction force acting on the rod 55.

Next, the stirring pile method of the present invention will be described. This stirring pile construction method forms a columnar improved body in the ground in order to improve the ground 50, and can be constructed using the stirring pile construction device 5 described above.

Now, as shown in FIG. 10, when there is an obstacle 95 such as a structure or railroad facility near the ground at the portion of the ground 50 to be improved, it should be placed at an appropriate position on the side of the obstacle 95. The stirring pile construction device 5 is installed.

Then, the inclination angle of the slide table 73 is adjusted to α degrees by the adjusting means 72, and the support columns 73 of the slide table 56 are placed on the ground 50. Further, in this case, the first rod 55a is connected to the power swivel 57 and the hydraulic cylinder 58 is operated to operate the power swivel 5
Place 7 in the lower limit position.

Next, as shown in FIG. 11, the first rod 5
The connection between 5a and the power swivel 57 is disconnected and the power swivel 57 is moved to the upper limit position by operating the hydraulic cylinder 58. At this time, the lower end of the first rod 55a is supported by the ground 50, and the upper end of the first rod 55a is supported by the rod chuck 74a.
Support in. Further, the support column 93 of the vehicle body 60 with the crawler is extended and grounded to the ground 50.

Next, the first rod 5 is moved by the rod chuck 74.
Power swivel 5
7 is moved upward to connect the second rod 55b between the first rod 55a and the power swivel 57.

Next, as shown in FIG. 12, the rod 55 and the stirring blades 53, 54 are rotated by the power swivel 57, and the power swivel 57 is moved downward by the hydraulic cylinder 58 as it is.
3, 54 are penetrated into the ground 50. At this time, the solidified material 52 is discharged at a low pressure from the discharge port 98 of the first rod 55a, and the solidified material 52 and the loose soil around the first rod 55a are stirred by the stirring blades 53 and 54.

After the power swivel 57 reaches the lower limit position, the remaining rods 55c, 55d.
.. Connect 55n in sequence and penetrate. When the rod 55 penetrates, the solidified material 52 is discharged from the discharge port 98 at a low pressure in the small diameter section 61 up to a certain depth.

After the small-diameter section 61 has passed, when the large-diameter section 62 penetrates, as shown in FIG. 13, the injection nozzle 59 at the tip of the stirring blade 53 is used together with the discharge of the solidifying material 52 from the discharge port 98. Then, the solidifying material 52 is injected at high pressure. As a result, the soil loosens in the range of the diameter larger than the rotating diameter of the stirring blade 53, and the loosened soil and the solidifying material 52 are mixed with each other.
It is agitated by 3, 54 and the solidified material 52 injected at high pressure.

In this way, after the rod 55 is penetrated to a predetermined depth to stir the solidifying material 52 and loose soil, the power swivel 57 is slid upward while the rod 55 is rotated in the reverse direction, and the power swivel 57 is slid upward. Slides to the upper limit position, move the mth rod 55m to the rod chuck 74
Then, the n-th rod 55n on it is separated. Similarly, one work is completed by pulling up the remaining rods 55 and sequentially separating them.

Thereafter, by performing curing for a certain period of time, as shown in FIG. 14, the small diameter section 61 and the large diameter section 6 are formed.
A soil cement column 96, which is a column-shaped (pile) -shaped improvement body, is formed in 2.

After the soil cement column 96 is formed at a predetermined position in this way, the stirring pile construction device 5 is moved to move a plurality of soil cement columns 96 over a certain range as shown in FIG. Form.

In this case, one soil cement column 9
Since the curing period is required after forming 6, the next soil cement column 96 is formed, for example, by leaving one. In this way, a plurality of soil cement columns 96 are formed intermittently, and after these soil cement columns 96 have hardened to some extent, a space between adjacent soil cements 96, 96 provided with a gap therebetween. Then, a soil cement column 96 is newly formed.

By doing so, the small diameter portions 96a of the adjacent soil cement columns 96, 96 which are agitated by the agitating blades 53, 54 are prevented from overlapping each other, and the large diameter portion 96b of the agitating nozzle 59 is agitated. Can be wrapped around each other.

As a result, it is possible to prevent the stirring blades 53 from colliding with the already hardened soil cement columns 96, and it is possible to wrap a part of the adjacent soil cement columns 96, 96. The soil cement 96 can be integrated to increase its strength.

As described above, according to the stirring pile construction method of the present invention, since the soil cement column 96 which is a columnar improvement body can be formed obliquely to the vertical direction, the ground 50 is to be improved near the ground. Even if there are structures, railway equipment, etc., it is possible to form an improved body diagonally from the side of these equipment toward the bottom. Therefore, the agitation pile construction method of the present invention is suitable for improving directly under a roadbed provided with a railroad track or an overhead wire.

Further, according to the stirring pile construction apparatus 5 of the present invention, by attaching the straight-moving holding means 80 to the rod 55, the displacement of the rod 55 can be prevented, as will be described below, which improves The body can be accurately formed in a predetermined position and its shape can be accurately formed.

FIG. 16 shows the displacement of the rod 55 in the horizontal direction, and FIG. 17 shows the displacement of the rod 55 in the vertical direction. The black circles in FIGS. 16 and 17 indicate the straightness maintaining means 80.
In the case where is not attached, the mark X indicates the case where the straight-movement holding means 80 is attached at a position 6.5 m from the tip of the rod 55.
The mark indicates that the straightness holding means 80 is 6.5 from the tip of the rod 55.
The figure shows the case where it is attached at the position of m and the position of 13.0 m.

As can be seen from FIGS. 16 and 17, when the two straightness holding means 80 are attached, the positional deviation in both the horizontal direction and the vertical direction is significantly reduced as compared with the case where the two are not attached. is doing. However, when only one straight advancing holding means 80 is attached, the positional deviation in the vertical direction is relatively large, so it is preferable to attach two or more straight advancing holding means 80.

[0078]

As described above, according to the stirring pile construction method of the present invention, an improved body can be formed obliquely to the vertical direction, so that a structure, railway equipment, etc. near the ground where the ground should be improved. Even if there is, the improvement can be formed obliquely from the side of these facilities to directly below.

According to the stirring pile construction device of the present invention,
Since the straight advancing holding means is attached to the rod, the displacement of the rod can be prevented, and thus the improved body can be accurately formed in a predetermined position with an accurate shape.

[Brief description of drawings]

FIG. 1 is a view showing a stirring pile construction device according to the present invention.

FIG. 2 is a diagram showing a first rod, a stirring blade, and a pilot bit of the stirring pile construction device according to the present invention.

FIG. 3 is a diagram showing a second rod to an n-th rod of the stirring pile construction device according to the present invention.

FIG. 4 is a diagram showing a standby state of the stirring pile construction device according to the present invention.

FIG. 5 is a view showing a state in which the rod of the stirring pile construction device according to the present invention is vertical.

FIG. 6 is a diagram showing a moving state of the stirring pile construction device according to the present invention.

FIG. 7 is a view showing a straight-moving holding means of the stirring pile construction device according to the present invention.

FIG. 8 is a view showing a state in which the straight-moving holding means of the stirring pile construction device according to the present invention is opened.

FIG. 9 is a view showing another embodiment of the straightness maintaining means according to the present invention.

FIG. 10 is a diagram illustrating a stirring pile method according to the present invention.

FIG. 11 is a diagram illustrating a stirring pile method according to the present invention.

FIG. 12 is a diagram illustrating a stirring pile method according to the present invention.

FIG. 13 is a diagram illustrating a stirring pile method according to the present invention.

FIG. 14 is a diagram illustrating a stirring pile method according to the present invention.

FIG. 15 is a view showing an improved body formed by the stirring pile method according to the present invention.

FIG. 16 is a diagram showing a horizontal positional displacement amount of a rod in the stirring pile device according to the present invention.

FIG. 17 is a diagram showing a vertical positional displacement amount of a rod in the stirring pile device according to the present invention.

[Explanation of symbols]

5 Stirring pile construction equipment 50 ground 52 Solidifying material 53,54 Stirring blade 55 rod 56 slide table 57 Power Swivel (Drive) 58 Hydraulic cylinder (slide means) 59 injection nozzle 66 pilot bits 72 Adjustment means 80 Straightness maintaining means

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kiyoshi Kuwahara             2-2-2 Yoyogi, Shibuya-ku, Tokyo East Japan             Passenger Railway Co., Ltd. (72) Inventor Hiroshi Abe             2-2-2 Yoyogi, Shibuya-ku, Tokyo East Japan             Passenger Railway Co., Ltd. (72) Inventor Tomoki Murano             Maeda 2-1026 Fujimi, Chiyoda-ku, Tokyo             Construction Industry Co., Ltd. (72) Inventor Katsuhiro Kusuhara             Maeda 2-1026 Fujimi, Chiyoda-ku, Tokyo             Construction Industry Co., Ltd. (72) Inventor Takeo Suzuki             Maeda 2-1026 Fujimi, Chiyoda-ku, Tokyo             Construction Industry Co., Ltd. (72) Inventor Abiko Hiroyasu             4-20 Sendagaya, Shibuya-ku, Tokyo Japan Integrated waterproofing             Within the corporation (72) Inventor, Koji Ito             4-20 Sendagaya, Shibuya-ku, Tokyo Japan Integrated waterproofing             Within the corporation F-term (reference) 2D040 AB03 AC04 AC05 BA08 BB02                       BB03 BC00 BD05 CA01 CB03                       DA11 DB07 EA01 EA11 EA18

Claims (7)

[Claims] 1. A solidification material that penetrates into a soft ground while rotating a rod equipped with a stirring blade and is discharged from near the tip of the rod and loose soil around the rod are mechanically treated by the stirring blade. A stirring pile construction method for forming a columnar improved body by stirring in a vertical direction, wherein the improved body is formed in an oblique direction with respect to the vertical direction. 2. The stirring pile construction method according to claim 1, wherein the straightness when the rod penetrates is held by a straightness holding means. 3. The stirring pile construction method according to claim 1, wherein the solidified material is injected at high pressure from the stirring blade in a direction substantially perpendicular to the central axis of the rod. 4. A pilot bit, which extends from the tip of the rod in the penetrating direction and has an acute tip, prevents lateral displacement of the tip of the rod. Item 5. The stirring pile method according to any one of items 1 to 3. 5. A rod for penetrating soft ground, a stirring blade attached to the rod, and a solidifying material discharging means for discharging the solidifying material from the vicinity of the tip of the rod.
A rod chuck for slidably and chuckably supporting the rod; a rotation driving means for rotating the rod; a slide table for fixing the rod chuck and slidably holding the rotation driving means; The solidifying material includes slide means for sliding the rotation driving means to penetrate the rod, and adjusting means for adjusting an inclination angle of the slide table with respect to the vertical direction in order to adjust a penetration angle of the rod with respect to the vertical direction. In a stirring pile construction device for forming a columnar improved body in the soft ground by mechanically stirring the loose soil around the rod and the stirring blade with the stirring blade, the rod is predetermined in the vertical direction. A straightness holding means for holding the straightness of the rod when it obliquely penetrates is provided, A stirring pile construction device, characterized in that a good body is formed obliquely to the vertical direction. 6. The agitating blade is provided with one or a plurality of injection means for injecting the solidified material under high pressure in a direction substantially perpendicular to the central axis of the rod. The stirring pile construction device described in. 7. The stirring pile construction device according to claim 5, wherein a pilot bit that extends in the penetrating direction and has a sharp tip is provided at the tip of the rod.