JP2010180647A - Agitating head of excavating and agitating machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an agitating head of an excavating and agitating machine, which can perform sufficient agitation without capturing large gravel in soil. <P>SOLUTION: This agitating head of the excavating and agitating machine includes: an excavating shaft 1; a radially-elongated excavating blade 2 which is fixed to a leading end of the excavating shaft 1; a radially-elongated anti-corotation material 3 which is attached above a position of the attachment of the excavating blade 2 to the excavating shaft 1 in such a manner as to be freely rotated on the excavating shaft 1; a radially-elongated agitating blade 4 which is fixed above a position of the attachment of the anti-corotation material 3 to the excavating shaft 1; and an auxiliary blade 6 which is attached in such a manner as to be elongated upward and downward from the anti-corotation material 3. The auxiliary blade 6 has flexibility. Even when the large gravel is sandwiched between the excavating blade 2 and the agitating blade 4, and the anti-corotation material 3, the gravel can pass through by virtue of the bending of the auxiliary blade 6. This can prevent the anti-corotation material 3 from being rotated together with the excavating blade 2 and the agitating blade 4. Thus, since soil around the anti-corotation material 3 and soil pushed and rotated by the excavating blade 2 and the agitating blade 4 are properly agitated, a good-quality soil improving body can be obtained. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a stirring head of an excavating stirrer. More specifically, the present invention relates to an agitation head of an excavating agitator used in a method for obtaining a columnar ground improvement body by mixing and agitating contaminated soil, soft ground or the like with a cement-based solidifying material liquid and curing.

The implementation method of the construction method for obtaining the ground improvement body will be described with reference to FIG.
The agitation head 100 is attached to the tip of an excavation rod R such as an earth auger EA which is a known driving means. The excavation rod R is rotated by a drive source of the earth auger EA, and a cement-based solidification material liquid is supplied to the agitation head 100 through a hollow portion of the excavation rod R from a solidification plant (not shown) attached to the earth auger EA. It has come to be.
When the excavation rod R is rotated and rotated, the agitation head 100 excavates and agitates the soil while entering the soil. At the same time, when the cement-based solidifying material liquid is supplied into the soil from the stirring head 100, the excavated soil and the cement-based solidifying material liquid are mixed together. For this reason, if it hardens | cures through fixed time, the hard ground shape | molded in the column shape will be obtained.

There exists patent document 1 as a prior art example of the said stirring head 100 used for said ground improvement construction method.
As shown in FIG. 4, the agitation head 100 includes a excavation shaft 102 attached to the tip of a rotating excavation rod R, and is fixed to the distal end side of the excavation shaft 102 and extends radially from the excavation shaft 102. Excavation blade body 103 extending, excavation blade group 104 attached to the excavation blade body 103 downward at substantially equal intervals, and a co-rotation preventing material rotatably attached to the excavation shaft 102 above the excavation blade body 103 110 and stirring blades 108 and 109 fixed to the excavation shaft 102 above the co-rotation preventing material 110.
The co-rotation preventing member 110 is set to be about 100 mm longer than the excavation blade body 103 so that the outer end thereof is outside the excavation blade body 103. Therefore, the co-rotation preventing material 110 bites into the earth wall that has been excavated in a cylindrical shape during rotation, and prevents co-rotation with the excavating blade 103 and the stirring blades 108 and 109.
As a result, the soil excavated by the excavating blade body 103 collides with the stationary co-rotation preventing material 110 and further collides with the stirring blades 108 and 109, so that the soil is finely crushed and efficiently stirred and kneaded with the solidified material liquid. be able to.

However, the conventional example has a problem that the stirring effect is insufficient.
That is, there is a large block of gravel in the soil, and the large gravel may be caught between the co-rotation prevention material 110 and the excavation blade 103, or may be caught between the co-rotation prevention material 110 and the stirring blade 109. . In this case, since the co-rotation prevention material 110 is only restrained by the surrounding soil, the binding force is weak, and when the gravel is sandwiched, the co-rotation prevention material 110 rotates together with the excavation blade body 103 and the stirring blade 108.109, and Stirring is no longer possible. Also, any of the wings may be deformed or damaged.
In order to prevent such a problem, both the distance d1 between the co-rotation prevention material 110 and the excavation blade 103 and the distance d2 between the co-rotation prevention material 110 and the stirring blade 109 pass through common gravel, It is enlarged to some extent.
However, since the natural strata often have a gravel-free clay layer and a gravel layer, if the gap between the blades d1 and d2 is large as described above, a co-rotation preventing material is present when there is no gravel. Since the soil around 110 and the soil above and below it do not mix, there is a problem that the stirring effect by the wings is weakened, and the soil excavated with great difficulty does not mix well with the cement-based solidifying material liquid.

JP 2005-325548 A

  In view of the above circumstances, an object of the present invention is to provide a stirring head of an excavating stirrer that can sufficiently stir without encroaching on large gravel in the soil.

The agitation head of the excavator agitator according to the first aspect of the present invention includes an excavation shaft, a radially extending excavation blade fixed to the tip of the excavation shaft, and a position around the excavation shaft above the attachment position of the excavation blade on the excavation shaft. A rotation-preventing material extending in the radial direction rotatably attached to the shaft, a stirring blade extending in the radial direction fixed above the mounting position of the rotation-preventing material on the excavation shaft, and a vertical movement from the rotation-preventing material The auxiliary wing is attached so as to extend, and the auxiliary wing has flexibility.
The stirring head of the excavating stirrer according to the second invention is the stirring head according to the first invention, wherein the upper edge of the auxiliary blade extends near the lower edge of the stirring blade, and the lower edge of the auxiliary blade extends near the upper edge of the excavating blade. It is characterized by being.

According to the first invention, even if a large gravel is sandwiched between the excavating blade or the stirring blade and the common rotation preventing material, the auxiliary blade is passed through by bending, so that the common rotation preventing material is shared with the excavation blade or the mixing blade. It can be prevented from turning. For this reason, since the soil around the co-rotation prevention material and the soil pushed around by the excavation blade or the stirring blade are well stirred, a good quality ground improvement body can be obtained.
According to the second invention, since the gap between the upper and lower edges of the auxiliary blade and the stirring blade or the excavation blade is small, the soil around the co-rotation prevention material and the soil pushed by the excavation blade or the stirring blade are good. Since it is agitated, a ground improvement body of good quality can be obtained.

It is a front view of the stirring head which concerns on one Embodiment of this invention. It is explanatory drawing of the use condition of the stirring head of FIG. It is explanatory drawing of a ground improvement construction method. It is a front view of the conventional stirring head.

Next, an embodiment of the present invention will be described with reference to the drawings.
A stirring head A according to an embodiment of the present invention will be described with reference to FIG.
Reference numeral 1 denotes an excavation shaft, and a connecting portion 12 is formed at the upper end of the shaft body 11. The connecting portion 12 is a prism portion for connecting to the excavation rod R shown in FIG.
A cutting edge 13 is attached to the lower end of the shaft body 11. The cement solidifying material liquid discharge port 14 is also provided so as to open at the lower end of the shaft body 11.

An excavation blade 2 is fixed to the lower end portion of the excavation shaft 1 so as to extend in the radial direction. A blade 21 for cutting soil is attached to the lower edge of the excavating blade 2.
A co-rotation prevention material 3 is rotatably attached to the excavation shaft 1 via a boss 31 so as to extend in the radial direction at an intermediate portion of the excavation shaft 1, that is, above the excavation blade 2.
The length of the co-rotation preventing material 3 is about 100 mm longer than the length of the excavating blade 2. That is, the outer end portion of the co-rotation preventing material 3 is adapted to bite into the side wall in the dug soil.

Agitation blades 4 and 5 are fixed to the upper end of the excavation shaft 1. The stirring blades 4 and 5 both extend in the radial direction from the excavation shaft 1 and intersect each other at right angles.
In the present embodiment, two stirring blades are used, but one stirring blade or three or more stirring blades may be used.

An auxiliary wing 6 is attached to the co-rotation preventing material 3. The auxiliary wing 6 is obtained by fixing a sheet 61 of a flexible material such as rubber to the side surface of the co-rotation preventing member 3 with a bolt 63 or the like through a contact plate 62.
The auxiliary wing 6 does not bend even when the excavated soil is pushed, but it may be bent if the gravel or the like is pushed and has flexibility enough to pass. As long as there is such a flexible material, any material other than the rubber described above may be used.

The lower edge of the auxiliary blade 6 extends downward to near the upper edge of the excavating blade 2.
The upper edge of the auxiliary blade 6 extends upward to near the lower edge of the stirring blade 4.
A distance D1 between the lower edge of the auxiliary blade 6 and the upper edge of the excavating blade 2 is, for example, about 5 cm, and is smaller than 15 to 20 cm of the gap d1 of the conventional example.
Further, a distance D2 between the upper edge of the auxiliary blade 6 and the lower edge of the stirring blade 4 is, for example, about 5 cm, which is smaller than 15 to 20 cm of the gap d2 of the conventional example.

Next, the usage state of the stirring head A of the present embodiment will be described with reference to FIG.
FIG. 2 shows a state where the excavation head A excavates the soil, and the wing tip of the co-rotation prevention material 3 is bitten into the side wall of the soil dug down (in the figure, the co-rotation prevention material 3 is viewed from the side. The biting state is not shown in the figure).
The dots in the soil indicate the soil e that has been excavated and stirred.
While the agitation head A rotates, the excavation blade 2 and the agitation blades 4 and 5 rotate around the excavation shaft 1, but the co-rotation preventing material 3 stops because the rotation of the excavation shaft 1 is allowed in the boss 31. ing. For this reason, a shearing action occurs between the soil e to which no rotational force is applied around the co-rotation preventing material 3 and the soil e to which the rotational force is applied by the excavating blade 2 or the stirring blades 4 and 5. The mixture is stirred and well mixed with the cement-based solidifying material liquid supplied from the discharge port 14 into the soil.

Then, when there is gravel 5 in the excavated soil, it may be pushed between the excavation blade 2 and the stirring blade 4 and the co-rotation prevention material 3.
In such a case, if the gravel 5 is large, the auxiliary wing 6 turns over and escapes the gravel 5, so that the co-rotation preventing material 3 does not rotate together.
Further, when the gravel 5 is small, it passes through the gaps D1 and D2, so that the co-rotation preventing material 3 does not rotate.
In this way, even if the gravel 5 is mixed in the soil, the co-rotation preventing function of the co-rotation preventing material 3 is achieved, so that the soil is not sufficiently stirred.

  Further, since the gravel 5 can be released, the interblade gaps D1 and D2 can be reduced. Therefore, the soil around which the rotational force around the co-rotation preventing material 3 is not applied and the soil to which the rotational force is applied by the excavating blade 2 and the stirring blades 4 and 5 are mixed together without separation. It will be. From this point, the stirring effect is enhanced.

DESCRIPTION OF SYMBOLS 1 Drilling shaft 2 Drilling blade 3 Co-rotation prevention material 4 Stirring blade 6 Auxiliary blade

Claims (2)

Drilling shaft,
A radially extending excavation blade fixed to the tip of the excavation shaft;
A joint rotation preventing material extending in the radial direction and rotatably mounted around the excavation shaft above the excavation shaft on the excavation shaft;
A stirring blade extending in the radial direction and fixed above the mounting position of the co-rotation preventing material on the excavation shaft;
An auxiliary wing attached so as to extend vertically from the co-rotation prevention material,
A stirring head of an excavating stirrer, wherein the auxiliary blade has flexibility. The agitation head of an excavation agitator according to claim 1, wherein the upper edge of the auxiliary wing extends near the lower edge of the agitation wing, and the lower edge of the auxiliary wing extends near the upper edge of the excavation wing. .

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