JPS5829374B2 - Mixing stirring blade device for cut soil in soil improvement machine - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a ground improvement machine that improves the ground into a columnar shape by mechanically mixing and solidifying soil and filler for foundation work, etc. This invention relates to a cutting soil mixing agitation blade device for efficiently performing agitation and mixing.

Conventionally, a ground improvement machine that improves the ground into a columnar shape rotates and excavates an excavation shaft 1 equipped with excavation blades 2 and stirring blades 3 using a predetermined excavation mechanism, as shown in Fig. 1, and rotates the excavation shaft during excavation or pulling out. A filler such as sodium silicate and cement milk is filled with a filler material such as sodium silicate and cement milk at a low pressure through a fluid passage (not shown) provided in the container 1, and solidified by forcible stirring.

However, this type of soil improvement machine uses a mixing head to drill holes in the soil, supplies filler material at low pressure into the gaps in the cut soil, and forcibly mixes and stirs the filler material and soil. It can be easily applied to loose soil and silt-based ground, but in clayey soil, especially hard clayey soil or beet layer, the ground to be improved and the stirring blades work together to efficiently remove the cut soil and filler material. It was impossible to mix and stir well.

Therefore, in conventional soil improvement machines, the mixing head is moved back and forth repeatedly to increase the mixing efficiency, which results in an extremely low work efficiency and a large amount of waste because the filler material is not mixed effectively. There were other drawbacks.

In addition, in order to increase the stirring efficiency, it is necessary to constantly consider the suitability of blending filler materials that are appropriate to the soil properties, and there are many problems such as the strength of the improved soil being highly dependent on the soil properties.

This invention was made in order to improve the shortcomings of the conventional construction methods mentioned above, and is the most effective ground improvement machine for improving the ground of sandy soil, silt soil, clay soil, beet layer, or alternate layers thereof. The present invention provides a mixing agitation blade device for cutting soil.

Hereinafter, one embodiment of the present invention will be described in detail with reference to FIGS. 2 and 3.

In the figures, parts and parts corresponding to those of the conventional example will be described with the same reference numerals.

FIG. 2 is a sectional view showing an embodiment according to the present invention.
The excavation shaft 1 is in the state of being dug into the soil, and has an excavation blade 2 having a predetermined excavation diameter Da, and an agitation blade 3 located above the excavation blade 2 and having approximately the same diameter as the excavation blade 2. It is fixed in multiple stages.

On the other hand, between the excavation blades 2 and the stirring blades 3 of the excavation shaft 1 and between the upper and lower stirring blades 3, there is provided an anti-warping device which is rotatable on the excavation shaft 1 and has a diameter Db larger than the excavation diameter Da. 4
is inserted.

Among them, the sag prevention device 4 may be provided between the excavation blade 2 and the stirring blade 30, or may be provided between the stirring blades 3.

As shown in FIG. 2, the above-mentioned warping device 4 is constructed by fixing two warping prevention wings 6 to a sleeve-shaped boss 5 that is loosely fitted onto the excavation shaft 1. Even when the excavation shaft 1 rotates, it has a diameter Db larger than the excavation diameter Da, so it does not rotate and is propelled into the soil.

Incidentally, three or more of the above-mentioned anti-twist blades 6 may be fixed to the boss 5.

Further, the co-rotation prevention device 4 is provided with bosses 7a and 7 on the excavation shaft 1 located above and below the boss 5 to prevent the excavation shaft 1 from moving up and down beyond a predetermined interval during digging or withdrawal of the excavation shaft 1.
b is fixed.

Next, a case in which ground improvement is performed using the stirring blade device equipped with the above-mentioned anti-slip device 4 will be described in detail.

As shown in the figure, when the excavation shaft 1 to which the excavation blades 2 and stirring blades 3 are fixed is rotatably excavated into the soil by a predetermined excavation mechanism,
A hole with an excavation diameter Da is formed in the soil, and the anti-slip device 4, which has a diameter Db larger than the excavation diameter Da, does not rotate and is propelled into the soil as the excavation shaft 1 excavates. go.

Therefore, the soil clod excavated by the excavation blade 2 which is placed at the tip of the excavation shaft 1 becomes integral with the excavation blade 2, but the rotation of this soil clod is stopped by the mutual kink prevention device 4.

That is, since the excavation blades 2 and stirring blades 3 of the excavation shaft 1 are rotating in the same direction regardless of whether the excavation shaft 1 is being excavated or being pulled out, the excavated soil mass is also rotating integrally.

Therefore, the rotation of the earth clod is temporarily stopped by the casing prevention device 4 provided between the excavation blade 2 and the stirring blade 3 of the excavation shaft 1 and between the upper and lower stirring blades 3. Mixing and agitation of the soil clod is carried out by the mutual kink prevention blade 6, the excavation blade 2, and the stirring blade 3.

Therefore, a predetermined filler material is supplied at low pressure from a fluid passage (not shown) provided in the excavation shaft 1, and ground improvement is performed while mixing and stirring the cut soil mass and the filler material.

As explained above in detail, the stirring blade device of the mixing head according to the present invention has a simple structure, and also forcibly stops the cut soil together with the excavation blades during soil cutting, so that it can interact with the filler material. This is a device that improves stirring efficiency.

Therefore, according to the device according to the present invention, it is possible to improve the ground with the most effective and high strength for sandy soil and gravelly soil.

In addition, even when soil improvement is carried out in a clay layer, the cut soil does not remain in the same place as in the conventional case and is sufficiently stirred, so there is no need to repeat the work of digging and pulling out the excavation shaft. Efficient ground improvement is possible with a single mixing and agitation at the time of extraction or extraction.

In addition, the amount of filler used can be limited to an optimum amount without waste, and stirring efficiency can be improved, resulting in significant effects such as greatly improving soil improvement work efficiency.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a conventional embodiment during excavation, FIG. 2 is a vertical cross-sectional view of an embodiment of the present invention during excavation, and FIG. 3 is a cross-sectional view taken along line A-A in FIG. It is. 1...Drilling shaft, 2...Drilling wing, 3...
...Stirring blade, 4...Both anti-warping device, 5
...Boss, 6...Both anti-warping wings, 7
a, 7b...Ring, Da...Excavation diameter, Db...Outer diameter of the same dimension warp prevention device.

Claims (1)

[Claims] 1 The excavation shaft equipped with excavation blades and stirring blades is rotated and pulled out using a specified excavation mechanism, and the button is pressed on a ground improvement machine that mixes and stirs soil and filler. An anti-seismic device having an anti-seismic blade having a diameter larger than the excavation diameter of the excavation blade, located between the stirring blades and/or between the agitation blades, is connected to the excavation shaft via a boss. A mixing and stirring blade device for cutting soil, characterized in that the blades are rotatably inserted into the cutting soil.