JPH11315534A - Mixing and stirring device of excavated soil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently improve soil down to a deep soil even in the case excavation resistance is increased as well as a large excavated diameter in the soft ground or soft ground, etc., mixed with stone or bedrock. SOLUTION: Excavation wings 11, 21 and 31 having a larger diameter as the wing goes up are provided. Common rotation preventing wings 12, 22 and 32 are so provided that wing sets 10, 20 and 30 are respectively made on the excavated wings. By the constitution, since excavation is made so as to become a larger diameter successively without having common rotation, even in the case excavation resistance is increased as well as a large excavated diameter, soil improvement can be made down to a deep soil efficiently.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mixing and stirring apparatus for excavated soil, and more particularly, to excavating soft ground into one or more excavation shafts in a columnar shape in civil engineering and construction (construction) foundation work. While mixing and stirring, a lime-based or cement-based slurry-type solidifying agent (hereinafter, also simply referred to as solidifying agent) is discharged, and the solidifying agent is mixed with the excavated soil, stirred, and solidified to form a ground. The present invention relates to a mixing and stirring device for excavated soil used for improvement.

[0002]

2. Description of the Related Art Conventionally, a technique described in Japanese Patent Publication No. 58-29374 has been known as a basic device of this kind for mixing and stirring excavated soil. It has a diameter (length) greater than the outer diameter (digging diameter) of the drilling wing between the drilling wing provided on the drilling shaft and the stirring blade, or between such stirring blades. This is a device in which a rotation preventing wing is rotatably mounted on a digging shaft via a boss to prevent co-rotation of digging soil to be digged.

In the technique described in Japanese Patent Publication No. 58-29374, when the ground (soil) is digged by the rotation of the digging shaft and the digging wing, the ground becomes a columnar shape having substantially the same diameter as the outer diameter of the digging wing. And simultaneously stirred by stirring blades. At this time, since the anti-corotating wing has a diameter larger than that of the excavating wing, both ends are pushed into a cylindrical portion, which is not excavated, that is, outside the cylindrical body, and penetrate into the ground. . And since this corotation prevention wing | blade is the state which was constrained by the hard ground because both ends are not excavated in planar view, it does not rotate around the axis of an excavation axis. As a result, the excavated soil that is going to rotate together with the excavating blade and the stirring blade in the excavation process is loosened without rotating together because the rotation is prevented by the anti-corotating blade. Then
The solidifying agent and the excavated soil are mixed and stirred by repeatedly moving forward and backward (vertically moving) while discharging the solidifying agent from the tip of the excavating shaft and rotating the excavating shaft forward or backward, and then solidified afterwards. Is improved.

[0004]

However, in the prior art, there is a problem that if the diameter of a portion to be improved in a plane is larger than, for example, 1 m, the application thereof is difficult. That is, even in soft ground, in relatively hard ground, or in a ground where rocks and rocks are mixed, as the excavation diameter increases, the excavation resistance increases accordingly. Therefore, excavation is often difficult when the ground is improved at a large diameter. In addition, the traveling speed of the excavation wing into the ground becomes slow, and it takes time for construction, and construction efficiency is significantly reduced. For this reason, it is difficult to improve the ground with a large diameter only in a small depth, and it is difficult to improve the ground to a deep layer. As a result, sufficient ground improvement cannot be performed, and serious problems such as ground subsidence occur after construction.

The present invention has been devised in view of such a problem of the conventional excavated soil mixing and stirring apparatus,
Its purpose is to make it possible to efficiently improve the ground to a deep layer even when the excavation diameter is large and the excavation resistance increases, such as in soft ground or soft ground where stones and rock masses are mixed.
An object of the present invention is to provide a mixing and stirring device for excavated soil.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to an apparatus for mixing and agitating excavated soil, comprising an excavating shaft provided with an excavating blade and a co-rotation preventing blade which is rotatable around the axis of the excavating shaft. A single anti-rotation wing is provided above one digging wing to form one wing set, and a plurality of said wing sets are provided, and each digging wing is positioned above the digging axis. Are relatively large, and the diameter of each co-rotation prevention wing is larger than the diameter of the excavating wing forming the wing set.
In other words, in a mixing and stirring apparatus for excavated soil provided with a plurality of excavating wings on an excavating axis, the excavating wings whose diameters are located above the excavating axis are relatively large, and On the wings with a diameter greater than the diameter of each of its excavation wings,
In addition, co-rotation prevention blades are provided which are rotatable around the axis of the excavation shaft.

In the case of excavating the ground by the above means and mixing and agitating, the excavation is first performed by the excavation blade having the smallest diameter at the lowermost end. However, since the diameter is small, the excavation resistance is small. Therefore, it is easy to dig into the ground. Subsequently, the co-rotation prevention wings of the wing set penetrate into the ground while digging into the outer edge of the digging diameter. Stopped by this co-rotating wing.
That is, since the first wing set can easily excavate and does not rotate together, mixing and agitation can be easily performed.

When the excavation further proceeds, and excavation is started by the excavation blade of the wing set above the excavation, the excavation is performed with a diameter larger than the previous excavation diameter. Since only the outer edge is excavated, excavation can be performed with a small excavation resistance. That is, for example, since the digging resistance of the hard ground on the ground surface portion is caused by a new digging portion outside the digging diameter that was previously digged, the digging resistance is lower than when digging the same diameter at once. Can be smaller.

In addition, as the excavation proceeds further, the co-rotation prevention wings, which form a wing group with the second excavation wing, enter the outer edge of the large excavation diameter, and the excavation proceeds in a stopped state in a plan view. However, since the co-rotation of the excavated soil that co-rotates with the excavation wing is prevented by the co-rotation prevention wing, the mixing and agitation can be performed well.

As described above, according to the apparatus of the present invention, even when the excavation diameter is large and the excavation resistance is increased in a relatively hard and soft ground or a ground in which stones and rocks are mixed, the excavation wings can be inserted into the ground. Progress is easy. Therefore, even if the diameter is large, the ground can be efficiently improved to a deep layer. In the present invention, the number of wing sets is not limited to two, and may be appropriately set according to the diameter and depth of excavation (ground improvement).

The above-mentioned means does not have a separate stirring blade, and is therefore suitable for soil improvement of relatively low viscosity such as sandy soil or silt type. However, in the case of high viscosity ground, It is good to provide a stirring blade. That is, in the above means, a stirring blade having a diameter substantially equal to or smaller than the diameter of the excavating blade is provided on the excavating shaft so as to be located above each co-rotation preventing blade. In this method, the excavated soil tries to co-rotate with the excavating wing and the stirring wing. However, the co-rotation preventing wing between the two wings prevents the co-rotation, so that the mixing and stirring are more efficiently performed. Done.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a mixing and stirring apparatus for excavated soil according to the present invention will be described in detail with reference to FIGS. However, the following embodiments are configured by joining steel components to each other by welding or the like. In the figure, reference numeral 101 denotes a substantially cylindrical (or hollow cylindrical) excavation shaft (rotation drive shaft), which is configured to be rotated by a rotation drive unit (not shown).
In the present example, three excavating wings 11, 21 and 31 having sequentially larger diameters are provided so as to project rightward and leftward at right angles from the vicinity of the tip side (the lower end of the excavating shaft). And
On each of the excavating wings 11, 21, 31, an anti-corotating wing 1 having a diameter larger than that of each excavating wing in a direction substantially perpendicular to the excavating axis 1.
2, 22, 32 are provided. However, the corotation prevention wings are mounted as follows (see FIG. 2).

Each of the co-rotation preventing blades 12, 22, 32 is rotatable about the axis G of the excavating shaft 101, on the outer periphery of the excavating shaft 101, on each of the excavating blades 12, 22, 32 in the excavating shaft 101. Thus, the annular body 5 having a cylindrical shape (circular pipe) with a small gap is mounted. However, rings 6a and 6b having a larger diameter than the excavation shaft 101 are provided on the excavation shaft 101 at a position where the upper end surface and the lower end surface of the ring body 5 come into contact.
1 and is provided integrally therewith to regulate vertical movement of the ring body 5. And on both outer sides in the diameter direction of this ring body 5,
Seen from above (in plan view), the excavator blades 11 and 12 just below it
The anti-corotating wings 12, 22, 32 with a diameter larger than 1, 31
It is formed so as to extend substantially linearly in a direction substantially perpendicular to the excavation shaft 101. In addition, each co-rotation prevention wing 12,2
2 and 32, the width direction (the vertical direction in FIG. 1) is the excavation axis 101.
Are substantially parallel to the direction of the axis G.

Thus, each of the co-rotation prevention wings 12, 22, 3
2 rotates with the excavating shaft 101 around the axis G of the excavating shaft 101 unless external force is applied to the excavating shaft 101 so as to stop the rotation of the excavating shaft 101. Part cuts into the periphery of the excavation site, and the excavation axis 10 of the anti-corotating wings 12,22,32
It is set so as to enter the excavated soil while the rotation of one turn is stopped.

In the present embodiment, a blade set 10, 2 composed of each of the excavating blades 11, 21, 31 and each of the co-rotation preventing blades 12, 22, 32.
0 and 30 are provided in order from the bottom three. However, in this example, stirring blades 13, 23, 23, slightly smaller than the diameter of the excavating wings forming the wing set, are located immediately above the anti-rotating wings forming each wing set.
33 are provided. The stirring blades 13, 23,
Reference numeral 33 denotes a strip-shaped member having a predetermined width.
It is formed so as to extend right and left at right angles to 01.

In the vicinity of the tip of the excavating shaft 101, a discharge port 1a for a slurry-like solidifying agent is provided, and a solidifying agent (not shown) passes through the inside (hollow portion) of the excavating shaft 101 from a pressure feed source. And is discharged into the excavated soil.

Next, the operation or effect of the embodiment will be described. Excavating the ground with this example device,
In the case of mixing and stirring, when the excavating shaft 101 enters the ground J while rotating to one side, excavation starts with the lowest and smallest excavating wing 11 (hereinafter also referred to as small excavating wing 11), J is excavated in the shape of a column having substantially the same diameter as the diameter D1 of the small excavation wing 11. At this time, since the diameter is small, the excavated soil k can be easily dug.
Then, the co-rotation prevention wings 12 (hereinafter, referred to as small co-rotation prevention wings 12) forming the blade set 10 with the small excavation wings 11 hit the outer edge of the excavation diameter (hereinafter, referred to as small excavation diameter), and cut into the ground while digging in. , The small co-rotation prevention wings 12
The end of the excavation shaft 101 is prevented from rotating around the axis G of the excavation shaft 101 in plan view when the end is restrained by the hard soil on the periphery.

Accordingly, the excavated soil k which is co-rotated by the small excavation wings 11 is prevented from rotating together with the small co-rotation prevention wings 12, and the excavated soil is mixed and stirred under this condition. Then, the stirring blade 13 immediately above the small co-rotation prevention blade 12 (hereinafter, referred to as the small stirring blade 13) enters the excavated soil and also rotates together with the excavation shaft 101. However, since the co-rotation is prevented by the small co-rotation preventing blades 12 between the two blades, the mixing and stirring are carried out well.

The excavation proceeds further, and the lower wing set 10
When the excavation starts with the excavation wings 21 (hereinafter, referred to as the middle excavation wings 21) forming the wing set 20 right above the outside, the outside of the small excavation diameter D1 already excavated by the small excavation wings 11 is excavated, and the ground is Excavation is performed at a diameter D2 of the middle excavation wing 21 (also referred to as a middle excavation diameter D2). At this time, the excavation resistance mainly depends on the small excavation diameter D.
Due to the new excavation site outside of 1, the already excavated small excavation D1 site has a small resistance, and therefore is excavated with a small excavation resistance to the medium excavation diameter D2.

Then, the co-rotation prevention wings 22 (hereinafter, referred to as the "co-rotation prevention wings 22") which form the wing set 20 with the middle digging wing 21 enter the outer edge of the middle digging diameter D2 and stop in a plan view. It gets into the ground while digging into it. And the excavated soil that is co-rotated by the middle excavation wing 21 is:
Among them, the co-rotation prevention blade 22 stops the co-rotation, and excavation, mixing, and stirring are performed under the state. Then, the stirring blade 23 immediately above (hereinafter, the medium stirring blade 23) enters the excavated soil. In this case, the excavated soil moving so as to rotate in the same direction is prevented from rotating in the middle co-rotation prevention blade 23, so that the excavated soil is appropriately mixed and stirred.

When the excavation further proceeds, and excavation starts at the excavation wing 31 (hereinafter, referred to as a large excavation wing 31) forming the uppermost wing set 30, the medium excavation already excavated by the intermediate excavation wing 21 is performed. The outer side of the diameter D2 is excavated, and the ground is
It is excavated to a diameter D3 of 1 (also referred to as a large excavation diameter D3). At this time, the excavation resistance mainly depends on a new excavation part outside the middle excavation diameter D2, but the resistance is small in the already excavated small excavation diameter D1 part and the medium excavation diameter D2 part, and therefore, with a small excavation resistance. It is excavated to a large excavation diameter D3.

Then, the anti-corotating wing 32 (hereinafter, referred to as a large anti-corotating wing 32) on the wing set 30 and the large digging wing 31 enters the outer edge of the large digging diameter D3 and stops in a plan view. It goes into the ground while biting. And the excavated soil co-rotated by the large excavation wing 31 is:
The co-rotation is stopped by the large co-rotation prevention blade 32, and excavation and mixing and stirring are performed under the state. Then, the stirring blade 33 immediately above (hereinafter referred to as a large stirring blade 33).
Penetrates into the excavated soil, and is gradually excavated to a large diameter at the surface portion, and the small excavation wing reaches a deep layer, and the excavated soil is mixed and stirred at the deep portion.

In the apparatus of this embodiment, excavation is started by the small excavation wings 11 and, at the same time, excavation is performed while a slurry-like solidifying agent is injected from the solidifying agent discharge port 1a at the tip of the excavating shaft 101, and mixing and stirring are performed. Is made. Then, by digging to a predetermined depth and repeating the forward / reverse rotation and forward / backward (vertical movement) of the digging shaft 101 an appropriate number of times, average mixing and agitation of the excavated soil and the solidifying agent are performed.

Thus, according to the apparatus of this embodiment, even when the diameter of the portion to be improved in plan view is large and the excavation resistance is large, the excavation is sequentially performed to increase in diameter. It is easy to go inside. Therefore, although the ground is improved into a stepped inverted cone shape, the excavation diameter is large in relatively hard ground and ground where stones and rocks are mixed,
Even if the excavation resistance increases, the ground can be efficiently improved to a deep layer.

In the above-described embodiment, since the stirring blades are added to each of the blade sets, both the excavating blades and the stirring blades move in such a manner that the earth mass moves in the direction of rotation, while the intermediate anti-rotation blades move. The co-rotation is blocked so as to be divided. Therefore, it has a high viscosity and is very effective for deep improvement with a large diameter in the improvement of the ground including stones and rocks.

However, it is relatively difficult to rotate the soil,
When the distance between the anti-corotating wings of the lower wing set and the excavating wings of the upper wing set is small, the excavating wings have the same function as the stirring wings, so that such stirring wings may not be provided. That is, the excavation wing has an effect of mixing and stirring the excavated soil around the excavation axis simultaneously with the excavation. What is necessary is just to set suitably according to soil quality.

The number of wing sets may be set as appropriate according to the soil quality, digging diameter or digging depth. The diameter of the excavation wing may be set to be relatively large at the upper position, and the degree may be set in accordance with the soil properties and the like. Further, the diameter of each co-rotation prevention blade may be larger than the diameter of the excavating blade forming the blade set, but if it is too large, it becomes difficult to bite. It is good to set appropriately so as not to cause biting difficulty and to ensure the co-rotation preventing action.

In the above-described embodiment, both the excavating wing and the co-rotation preventing wing, which constitute one wing set, are provided in a plan view so as to extend to the left and right of the excavation axis, in a straight line. Alternatively, three or more radial directions may be provided at unequal angular intervals. The same applies to the stirring blade. Also,
In the above-described embodiment, the excavating wing, the anti-corotating wing, and the agitating wing, which constitute one wing set, are exemplified as a pair provided at the same height portion of the digging shaft 101 in a double wing state. It may be provided as two wings or one wing. Furthermore, in the above-described embodiment, the excavating blade, the co-rotation preventing blade, and the stirring blade are both formed in a linear shape in a plan view, but may be formed in an arc shape or a V shape. In the above-described embodiment, an example in which the present invention is embodied in one excavation axis is illustrated. However, in the present invention, in a mixing and stirring apparatus for excavated soil having a plurality of excavation axes, the present invention can also be implemented in each excavation axis. .

[0029]

As is apparent from the above description, according to the apparatus of the present invention, the ground is improved into a stepped inverted conical shape, but the ground is excavated to have a large diameter and mixed and stirred. Therefore, even when the excavation diameter is large and the excavation resistance is increased in a relatively hard ground or a ground in which stones and rocks are mixed, the ground can be efficiently improved to a deep layer.

[Brief description of the drawings]

FIG. 1 is a front view showing a schematic configuration of an embodiment of a mixing and stirring apparatus for excavated soil according to the present invention.

FIG. 2 is a partially cutaway enlarged view of a portion near a front end in FIG. 1;

FIG. 3 is a plan sectional view taken along line AA in FIG. 2;

[Explanation of symbols]

 101 Excavating shaft 10, 20, 30 Blade set 11, 21, 31 Excavating blade 12, 22, 32 Anti-corotating wing 13, 23, 33 Stirring blade G Axis of excavating shaft

Claims (3)

[Claims] 1. A mixing and stirring apparatus for excavated soil comprising an excavating wing and an anti-rotating anti-rotation blade rotatable around the axis of the excavating shaft, wherein one anti-rotating wing is provided above one excavating wing. And one wing set is provided, a plurality of the wing sets are provided, and each excavation wing has a relatively large diameter above the excavation axis. Characterized by being larger than the diameter of the excavating wing forming the wing set,
Mixing and stirring equipment for excavated soil. 2. A mixing and mixing apparatus for excavated soil comprising a plurality of excavating wings on an excavating shaft, wherein the excavating wings whose diameter is located above the excavating shaft are relatively large, And a mixing and stirring device for excavated soil, wherein a co-rotation prevention blade having a diameter larger than the diameter of each excavation wing is provided on each excavation wing and rotatable around the axis of the excavation shaft. 3. The excavator according to claim 1, wherein a stirring blade having a diameter substantially equal to or smaller than the diameter of the excavating blade is provided on the excavating shaft so as to be located above each co-rotation preventing blade. The mixing and stirring apparatus for excavated soil according to claim 1 or 2, wherein