JP2779481B2 - Ground improvement machine - 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 machine and a ground improvement method for improving the ground into a columnar shape by stirring and mixing soil and a solidified material in foundation work or the like.

[0002]

2. Description of the Related Art Conventionally, such a ground improvement machine and a ground improvement method disclosed in, for example, Japanese Patent Publication No. 58-29375 are known. As shown in FIG. 5, this machine is provided with an excavating wing 1 at the lower end of a vertically excavating shaft 101.
02, the stirring blades 103, 103 are fixed to the excavating shaft 101 at an interval vertically, and the excavating shaft 10 is further fixed.
At the upper position of the excavating wing 102, a co-rotation prevention device 104, which is composed of a cylindrical body 105 having substantially the same diameter as the excavating diameter and is lowered with the lowering of the excavating shaft 101, is mounted.
5 is provided with anti-corotating wings 106, 106 whose tips extend to the vicinity of the excavating shaft 101 on the inner peripheral surface.

[0003] Then, the excavating blade 10
2. The excavating shaft 101 to which the agitating blades 103 are fixed is advanced by rotating the excavation while supplying the solidified material into the ground. Therefore, the soil excavated by the excavation wing 102 rotates together with the excavation wing 102 and the stirring wings 103, 103. The rotation is stopped, so that the soil is agitated and mixed.

[0004]

However, a part of the rotating soil is stopped by the anti-corotating blades 106, 106, and the anti-corotating blades 106, 106 and the stirring blades 103, 1 are stopped.
03 and only in the horizontal direction with stirring and mixing,
In particular, the soil in contact with the stirring blades 103, 103 still rotates together with the stirring blades 103, 103, and it takes a lot of time to uniformly mix and mix the soil and the solidified material, resulting in poor work efficiency. There was. Accordingly, the present invention has been made to solve the above problems, and provides a ground improvement machine and a ground improvement method for preventing the co-rotation and enabling the soil and the solidified material to be efficiently and uniformly stirred and mixed. Aim.

[0005]

In order to achieve the above object, a ground improvement machine according to the present invention comprises a digging blade fixed to a lower end of a digging shaft which is vertically digged into the ground while rotating. While excavating the ground by the rotation of the excavating wing, in a ground improvement machine that is configured to stir and mix the soil while supplying the solidifying material, on both sides of the excavating shaft, rotating with the rotation of the excavating shaft In addition, a pair of first stirring shafts that rotate and are mounted horizontally, and a plurality of second stirring shafts that are perpendicular to the first stirring shaft are fixed to each of the first stirring shafts.

Alternatively, a digging wing is fixedly provided at the lower end of a digging shaft that vertically descends into the ground while rotating, and digging the ground by rotation of the digging wing, while supplying a solidified material to the soil. In the ground improvement machine that is configured to stir and mix, on both sides of the excavation shaft, a distance between both ends has substantially the same dimension as the excavation wing, and rotates and rotates with the rotation of the excavation shaft. A pair of first stirring shafts are mounted horizontally, and a plurality of second stirring shafts perpendicular to the first stirring shafts are fixed to each of the first stirring shafts. Has a configuration centered on the intersection of the excavation axis and the first stirring axis and located on the surface of a sphere having a radius from the center to the tip of the first stirring axis. .

[0007]

The first stirring shaft rotates in the horizontal plane with the rotation of the excavating shaft, and rotates at the same time. With the rotation of the first stirring shaft, the plurality of second stirring shafts fixed to the second stirring shaft simultaneously rotate in the vertical plane. Accordingly, the soil that is rotated in the horizontal direction is also rotated in the vertical direction and is stirred intricately, so that co-rotation is completely prevented. And the second
Due to the rotation of the stirring shaft, a force acts on the soil in the tangential direction of the circular contour, and the direction of the force constantly changes with the rotation of each second stirring shaft. Can be efficiently mixed in a short time.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a ground improvement machine according to the present invention will be described below with reference to FIGS. A digging blade 2 having a required length is fixedly provided at a lower end of a digging shaft 1 which is formed of a cylindrical body and rotates vertically into the ground while rotating, and a stirring blade is provided above the digging blade 2. 3 are fixed in a cross shape. The stirring blade 3 is formed to have substantially the same length as the excavating blade 2.

A pair of first stirring shafts 4 and 4 are provided horizontally on both sides of the excavating shaft 1 between the excavating blade 2 and the stirring blade 3. The first stirring shafts 4, 4 are also substantially the same length as the excavating blade 2, and are provided so as to rotate in a horizontal plane and to rotate. In addition, each of the first
A plurality of second stirring shafts 5 perpendicular to each of the first stirring shafts 4 and 4 are fixed to the stirring shafts 4 and 4 at equal intervals. Each of these second stirring shafts 5 is rotated in a vertical plane as the first stirring shafts 4 and 4 rotate. In addition, the outer peripheral surface of the excavating shaft 1 is connected to a pipe 6 in the vicinity of a lower excavating blade 2 and an upper stirring blade 3, respectively, and is an ejection hole for supplying solidified material powder or milk into the soil. 6a and 6b are established.

FIG. 2 is an enlarged sectional view of a main part showing a rotating mechanism of the first stirring shafts 4, 4. As shown in FIG. The base ends of the first stirring shafts 4, 4 penetrate into the excavating shaft 1, are supported by bearings 7, 7, and have floating gears 8 fixed to the respective base ends.
In the excavation shaft 1, the lower end is the first along the central axis.
A fixed support shaft 9 located at substantially the same position as the stirring shafts 4 and 4 is suspended, and a fixed gear 10 meshed with the floating gears 8 is fixed to a lower end of the fixed support shaft 9. The support shaft 11 of the excavating blade 2 is also provided along the center axis of the excavation shaft 1, and is fixed to the inner peripheral surface of the excavation shaft 1 by a bracket 12.
Further, a drive gear 13 meshed with each of the floating gears 8 is fixed to an upper end of the support shaft 11.

Then, the excavating blade 2 rotates with the rotation of the excavating shaft 1, and the driving gear 13 rotates. And both first
Since the stirring shafts 4 and 4 rotate in the horizontal plane, and at the same time, the respective floating gears 8 and 8 at the base end rotate between the fixed gear 10 and the driving gear 13, the first stirring shafts 4 and 4 are accordingly moved. Rotate around its central axis, that is, rotate.

The ground improvement machine according to the present invention has the above-described configuration, and the operation will be described next. First, the excavating shaft 1 is rotated at a low speed and a high torque by a predetermined excavating mechanism (not shown), and the ground material is supplied from the lower ejection hole 6a of the excavating shaft 1 through the pipe 6 while the solidified material is supplied. Go moat vertically inside.

Then, the first stirring shafts 4 and 4 rotate in the horizontal plane with the rotation of the excavating shaft 1, and rotate at the same time. Furthermore,
The plurality of second stirring shafts 5 rotate in the vertical plane.
For this reason, the soil rotated in the horizontal direction by the first stirring shafts 4 and 4 is also rotated in the vertical direction by the plurality of second stirring shafts 5, and the soil is mixed in a complicated manner. Is completely prevented. In addition, the rotation of the second stirring shaft 5 causes a force to act on the soil in the tangential direction of the circular contour, and the direction of the force always changes with the rotation of each second stirring shaft 5. In addition, uniform stirring and mixing of the soil and the solidified material can be efficiently performed.
Also, in order to make the mixing of the soil and the solidified material more uniform, when the excavating shaft 1 is reciprocated, the solidified material is supplied from the upper ejection port 6b at the time of its reciprocation, that is, ascent.

Further, as shown in FIG. 3 and FIG.
The tip P of the stirring shaft 5 is centered on an intersection O between the center axis of the excavating shaft 1 and the center axes of the first stirring shafts 4 and 4, and a distance D from the intersection O to the tip C of the first stirring shaft 4. Sphere Q with radius
Is located on the surface of the ground, the spherical body Q matches the inner peripheral surface of the improved cylindrical portion A in the ground.
All the soil inside is reliably taken into the sphere Q and stirred.

Accordingly, even if the excavating shaft 1 is rotated at a low speed together with the supply of the solidified material, the mixing of the soil and the solidified material can be performed in a short time, so that an extremely uniform ground improvement pile can be obtained. Formed in time.

[0016]

As described above, the soil improvement machine and the ground improvement method according to the present invention have the first stirring shaft attached to the excavation shaft and rotated in a horizontal plane, and at the same time, the first stirring shaft is rotated. The second agitating shaft is fixed and rotated in the vertical plane, so that the soil that is rotated in the horizontal direction is also rotated in the vertical direction and is stirred in a complicated manner. Is prevented. In addition, by the rotation of the second stirring shaft, a force acts on the soil in the tangential direction of the circular contour, and the direction constantly changes, so that uniform stirring and mixing of the soil and the solidified material can be performed efficiently in a short time. It has the advantage that it can be performed.

In particular, the tip of each second stirring shaft is placed on the surface of a sphere whose center is the intersection of the excavating shaft and the first stirring shaft and whose radius is the distance from the center to the tip of the first stirring shaft. If the sphere is positioned so that it matches the inner peripheral surface of the improved cylindrical part in the ground, all the soil in the cylindrical part to be improved is taken into the sphere, so that the whole is uniformly stirred and mixed without leaving. Becomes possible.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part of a ground improvement machine according to the present invention.

FIG. 2 is a sectional view of a main part of a drilling shaft.

FIG. 3 is a longitudinal sectional view showing a use state.

FIG. 4 is a sectional view taken along line XX in FIG. 3;

FIG. 5 is a longitudinal sectional view of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Drilling shaft 2 Drilling blade 4 First stirring shaft 5 Second stirring shaft

Claims (1)

(57) [Claims] An excavating wing is fixedly mounted at a lower end of a digging shaft that vertically descends into the ground while rotating, and digs the ground by rotation of the digging wing, and supplies a solidified material while soil is excavated. In the ground improvement machine that is configured to stir and mix, on both sides of the excavation shaft, a distance between both ends has substantially the same dimension as the excavation wing, and rotates and rotates with the rotation of the excavation shaft. A pair of first stirring shafts are mounted horizontally, and a plurality of second stirring shafts perpendicular to the first stirring shafts are fixed to each of the first stirring shafts. The tip of the excavation axis and the first
A ground improvement machine characterized by being located on the surface of a sphere whose center is an intersection with a stirring shaft and whose radius is the distance from the center to the tip of the first stirring shaft.