JPH07197443A - Excavation and agitation method for soil improvement and device thereof - Google Patents

Abstract

PURPOSE:To obtain an excavation and agitation method by which a soft ground and a solidifying agent can be kneaded three-dimensionally and a soil-improving body having a uniform strength-characteristic as a whole can be constructed. CONSTITUTION:A plurality of vertical wanes 6 rotatably provided at a second agitating blade 5 are forcibly rotated by a preventive blade 8 against loose rotation as a unit and a pseudo-gear 9 to mix and agitate materials three- dimensionally by means of an agitation blade 3 and the respective vertical vanes 6 of the second agitation blade 5, when the second agitation blade 5 attached to the excavation shaft 4 to rotate the agitation blade 3 rotates with the agitation blade 3. By this mechanism, extremely uniform agitation and mixing 4-B, possible and further by the combination of the preventive blade 8 against loose rotation as a unit and the second agitation blade with vertical vanes 6, extremely uniform agitation and mixing is possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention improves a soft deep ground by injecting a cement-based solidifying material into a hole drilled in the ground and mixing the excavated in-situ sand and the solidifying material. The present invention relates to a so-called excavator and agitator used in a so-called deep mixing ground improvement method.

[0002]

2. Description of the Related Art In this type of deep-mixed ground improvement method for agitating and mixing in-situ sand and solidifying material to improve soft ground, cohesive soil adheres to an excavator and agitator and the ground to be improved. There is a case where a so-called co-rotation phenomenon occurs in which the digging and stirring device rotates together, and it cannot be said that stirring and mixing can be sufficiently performed.

Therefore, as a measure for preventing this co-rotation phenomenon, in the past, (1) an excavation stirring device equipped with a "co-rotation preventing vane" that does not rotate during excavation stirring (Japanese Patent Publication No. 58-29374).
No., mixing and stirring device for cutting soil in ground improvement machines),
(2) Devices such as an excavator and agitator (Japanese Patent Publication No. 59-3603, soft ground improvement method) in which the mixing and agitating blades rotate forward and backward relative to each other by a double pipe shaft have been proposed.

[0004]

However, the above-mentioned respective devices capable of preventing co-rotation have the following points to be improved. That is, in both the devices (1) and (2), the movement of the stirring blade is only on the plane perpendicular to the excavation axis, and three-dimensional mixing and stirring cannot be performed. Therefore, each of the conventional devices has a defect that the degree of mixing and stirring the soft ground and the hardening material is not improved, and the shear strength in the horizontal direction is relatively small.

As described above, in each of the above-described conventional excavating and stirring devices, three-dimensional mixing and stirring cannot be performed in spite of preventing the co-rotation phenomenon in order to surely perform stirring and mixing. However, it has not yet been said that the soil and sand to be improved and the solidifying material can be sufficiently mixed.

The present invention was devised in view of the above-mentioned circumstances, and an object thereof is to make it possible to mix and stir the soft ground and the hardened material in a three-dimensional manner surely, and to obtain uniform strength characteristics as a whole. An object of the present invention is to provide a digging and stirring device for ground improvement, which enables construction of a ground improvement body.

[0007]

DISCLOSURE OF THE INVENTION The excavation and agitation device of the present invention is configured to rotate on a plane perpendicular to the excavation axis, which is similar to the agitation blade, at a position near the agitation blade attachment position on the excavation axis. A second stirring blade formed in a cylindrical shape for promoting stirring is provided. A plurality of vertical blades that integrally rotate on a plane perpendicular to the rotation plane of the stirring blade are provided on the outer peripheral surface of the second stirring blade.

Further, in the vicinity of the mounting position of the stirring blade on the excavating shaft, together with the second stirring blade, a co-rotation preventing blade having a larger turning plane diameter than the excavating blade is provided, and a plurality of second stirring blades are provided. A part of the vertical blades of the vertical blades has a rotation plane intersecting with the co-rotation preventing wing portion. And, this part of the vertical blades, when the second stirring blade is rotated,
It is configured to come into contact with the co-rotation prevention wing that is locked by the ground outside the excavation range and to be rotated.

According to the excavation and agitation apparatus of the present invention having such a configuration, when the second agitation blade provided on the excavation shaft for rotating the agitation blade rotates together with the agitation blade, A plurality of vertically rotatably mounted vertical blades are rotated by co-rotation prevention blades, and three-dimensional mixing and stirring are performed with the stirring blade and each vertical blade of the second stirring blade, enabling extremely uniform stirring and mixing. And

Further, the combination of the co-rotation preventing blade and the second stirring blade equipped with the vertical blade enables extremely uniform stirring and mixing. Moreover, by forcibly rotating each vertical blade of the second stirring blade by the co-rotation preventing blade, forced three-dimensional stirring and mixing is realized, and extremely uniform stirring and mixing is possible.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The excavation and stirring device for ground improvement of the present invention will be described below with reference to the illustrated embodiments.

An excavation shaft 4 having an excavation blade 2 and a stirring blade 3.
Is excavated and extracted while rotating in the ground to be improved, and the excavation and agitation device 1 for soil improvement that agitates and mixes the solidified material and the soil injected into the soil (see FIG. 1) is used. A second stirring blade 5 for promoting stirring, which is formed in a substantially cylindrical shape and rotates on a plane perpendicular to the excavation axis 4 similar to the stirring blade 3, is provided in the vicinity of the mounting position of the blade 3. ing. Further, on the outer peripheral surface of the second stirring blade 5, a plurality of vertical blades 6 that integrally rotate on a plane perpendicular to the rotation plane of the stirring blade 3 are provided.

The excavation and agitation device 1 in this embodiment is
A boss 7 (see FIG. 3) with respect to the excavation shaft 4 together with the second stirring blade 5 at a position near the stirring blade mounting position on the excavation shaft 4
A co-rotation preventing blade 8 having a larger rotation plane diameter than the excavating blade 2 and the stirring blade 3 is provided.

In addition, some of the vertical blades 6a of the plurality of vertical blades 6 provided on the second stirring blade 5 (see FIGS. 1 and 2) are longer than the other vertical blades 6 and have a rotating plane. Are designed so as to intersect the co-rotation prevention wing 8 part.
Then, the long vertical blade 6a is configured to be brought into contact with the co-rotation preventing blade 8 and the pseudo tooth 9 to be rotated when the second stirring blade 5 is rotated.

Further, the excavation and agitation device 1 in this embodiment will be described in detail. As shown in FIG. 1, the excavation blades 2 aligned on both ends of the excavation shaft 4 in the radial direction of the shaft and the upper portion thereof. A stirring blade 3 having a diameter equal to or smaller than that of the excavating blade 2 and aligned in a radial direction on both sides of the excavating shaft 4 is provided at a position. Each of these blades is driven by a drive device (not shown) mounted on the excavation shaft 4 to rotate about the excavation shaft 4 for excavation, extraction, stirring and mixing of the injected solidifying material and soil. It is possible.

Further, the excavation blade 2 is provided in the excavation stirring device 1.
A co-rotation preventing blade 8 is attached between the lower stirring blade 3 and the lower stirring blade 3 and in the vicinity of the two stirring blades above the upper stirring blade 3. The co-rotation preventing blade 8 has pseudo teeth 9, is long in both radial directions of the excavating shaft 4, has a plane parallel to the shaft, and has a diameter larger than those of the excavating blade 2 and the stirring blade 3. , Boss 7
It is rotatably and pivotally attached to the excavation shaft 4 via.

The ground improvement using the excavation and agitation apparatus for ground improvement of the present invention having such a structure is carried out as follows.

That is, while rotating the excavation blade 2 and injecting the excavation shaft 4 into the ground (not shown) to be improved, a solidifying material such as cement is injected from the tip of the excavation shaft 4 into the drilling hole. When excavating and reaching a predetermined depth, the shaft 4 is pulled out while rotating the stirring blade 3 and the second stirring blade 5, and the improved soil composed of the soil and the solidifying material is stirred and mixed.

At this time, when the second stirring blade 5 is rotated, some of the vertical blades 6a of the plurality of vertical blades 6 intersect the co-rotation preventing blade 8 and contact the co-rotation preventing blade 8. As a result, it can be rotated. As a result, the plurality of vertical blades 6 integrally rotate on a plane perpendicular to the rotation plane of the stirring blade 3.

The plurality of vertical blades 6 provided on the second stirring blade 5 integrally rotate on a plane perpendicular to the rotation plane of the stirring blade 3 so that the stirring blade 3 and the co-rotation preventing blade 8 are formed. Combined with the stirring effect, the mixed soil of the improved soil consisting of the soil and the solidifying material can be three-dimensionally mixed and stirred, which enables extremely uniform stirring and mixing.

FIG. 4 shows another embodiment of the present invention.
1 shows a forward and reverse rotation type excavation and agitation device. Here, the second stirring blade 5 is provided on the outer shaft 10 of the excavation stirring device 1, and the pseudo tooth 9 that rotates together with the inner shaft 11 is fixedly mounted on the inner shaft 11, and a plurality of teeth are provided on the second stirring blade 5. A part of the plane of rotation of the vertical blade 6 intersects with the pseudo tooth 9.

The vertical blades 6 of the second stirring blade 5 are rotated when a part of the rotation plane of the vertical blade 6 intersects with the pseudo tooth 9 when the second stirring blade 5 rotates, and is brought into contact therewith. Is configured.

FIG. 5 shows still another embodiment of the present invention, which shows a forward and reverse rotation type excavator and agitator.
Here, the excavation blade 2 fixed to the inner shaft 11 of the excavation and agitation device 1 is used.
And a pivoting stirring blade 12 pivotally attached to the outer shaft 10 via a boss 7 having pseudo teeth 9 fixed thereto by a connecting member 13. In addition, the second stirring blade 5 is provided near the outer shaft of the pivoting stirring blade 12.
And a part of the rotation planes of the plurality of vertical blades 6 provided on the second stirring blade 5 is the pivotal stirring blade 12 and the pseudo tooth 9.
So that it intersects with. Each of the vertical blades 6 of the second stirring blade 5 is rotated when a part of its rotating plane intersects with the pivoting stirring blade 12 and the pseudo tooth 9 when the second stirring blade 5 rotates. It is configured to be moved.

[0024]

As described above, the present invention has the following effects.

(1) When the second stirring blade provided on the excavating shaft for rotating the stirring blade rotates together with the stirring blade, a plurality of vertical blades rotatably provided on the second stirring blade are provided to prevent co-rotation. Can be rotated by. Therefore, it becomes possible to three-dimensionally perform mixing and stirring by the stirring blade and each vertical blade of the second stirring blade, and extremely uniform stirring and mixing becomes possible.

(2) By combining the anti-rotation blade and the second stirring blade with the vertical blade, extremely uniform stirring and mixing becomes possible. Moreover, since the long vertical blade of the second stirring blade can be forcibly rotated by the co-rotation preventing blade, forced three-dimensional stirring and mixing can be realized, and extremely uniform stirring and mixing can be performed.

As described above, according to the excavating and stirring apparatus of the present invention, it is possible to obtain a ground improvement body having isotropic strength characteristics due to the uniform stirring and mixing effect.

[Brief description of drawings]

FIG. 1 is a front view showing a ground excavation and agitation device of the present invention.

2 (a) is a schematic sectional view taken along the line AA of FIG. 1, and (b) is
It is a CC line arrow line view of (a).

3 is a schematic cross-sectional view taken along the line BB of FIG.

FIG. 4 shows another embodiment of the present invention and is a front view showing a forward and reverse rotation type excavation and agitation device.

FIG. 5 is a front view showing another embodiment of the present invention, showing a forward and reverse rotation type excavation and agitation device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Excavation stirring device, 2 ... Excavation blade, 3 ... Agitation blade, 4 ... Excavation shaft, 5 ... Second stirring blade, 6 ... Vertical blade, 6a ... Long vertical blade, 7 ... Boss, 8 ... Co-rotation prevention blade, 9 ... Pseudo tooth, 10 ... Outer shaft, 11 ... Inner shaft, 12 ... Pivoting stirring blade, 13 ... Connecting material.

Claims (5)

[Claims] 1. A method for excavating and stirring ground for improving the ground by stirring and mixing the solidified material and the soil injected into the ground, wherein a second stirring blade is provided on the drilling shaft of the drilling and stirring device, and the second stirring blade is used. , A plane portion perpendicular to the excavation axis similar to the stirring blade and a plane portion perpendicular to the rotating plane of the stirring blade are agitated, and are agitated three-dimensionally as a whole. Excavation and stirring method for ground improvement. 2. A digging and stirring device for ground improvement, which stirs and mixes the solidified material poured into the ground and soil, wherein the digging and stirring shaft of the digging and stirring device is rotated on a plane perpendicular to the shaft. A second stirring blade for promoting stirring formed in a substantially cylindrical shape is provided, and the outer peripheral surface of the second stirring blade is integrally rotated on a plane perpendicular to the rotation plane. An excavation and agitation device for ground improvement, which is provided with a plurality of vertical blades. 3. A co-rotation preventive device having a large flat surface diameter when rotated more than the excavating blade, which is loosely fitted to the excavating shaft via a boss together with a second stirring blade for promoting stirring. With the blade provided, the rotation plane of a part of the vertical blades in the plurality of vertical blades provided in the second stirring blade is configured to intersect with the co-rotation prevention blade portion, and in the second stirring blade 3. Each of the vertical blades is configured to be rotated when a part of the vertical blades comes into contact with the co-rotation preventing blade when it intersects with the co-rotation preventing blade portion. An excavation and agitation device for ground improvement as described. 4. A forward / reverse rotation type excavation and agitation device for agitating and mixing a solidified material and soil injected into the ground to improve the ground, and a second agitation blade is provided on the outer shaft, and at the same time as the inner shaft. A rotating pseudo tooth is fixed to the inner shaft, and a part of the rotation planes of the plurality of vertical blades provided on the second stirring blade is configured to intersect with the pseudo tooth, and in the second stirring blade, Each of the vertical blades is configured to be rotated when a part of the rotation plane of the vertical blade intersects and abuts the pseudo tooth when the second stirring blade rotates. Rotating ground excavator and agitator for soil improvement. 5. An excavating blade fixed to the inner shaft and a pivoting stirring blade which is pivotally attached to the outer shaft via a boss having pseudo teeth fixed thereto are connected by a connecting member, A second agitating blade is provided in the vicinity of the outer shaft of the agitating agitating blade, and a rotation plane of a part of a plurality of vertical blades provided on the second agitating agitating blade intersects with the agitating agitating blade and the pseudo tooth. Each of the vertical blades in the second stirring blade is rotated by causing a part of the rotation plane to intersect and come into contact with the pivotal stirring blade and the pseudo tooth when the second stirring blade rotates. A forward and reverse rotation type ground improvement excavation and agitation device characterized by being configured as described above.