JPS6349767B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a ground excavation method, in which a plurality of hollow rotating vertical shafts 1 are entirely covered with a cylindrical casing K, and each of the plurality of rotating vertical shafts 1 is rotated, and the The ground 2 is excavated by rotating or swinging a group of multiple rotating vertical shafts 1, and the hollow rotating vertical shaft 1
The present invention relates to a ground excavation method characterized by ejecting a liquid from a soil and mixing soil with the liquid.

An object of the present invention is to rotate a plurality of rotary vertical shafts individually within a cylindrical casing, and rotate or swing the rotary vertical shaft groups as a unit, so that the rotary vertical shaft groups can be rotated as a unit. Or, by the synergistic effect of rocking and the integral rotation of this group of rotating vertical shafts or the independent rotation of each rotating vertical shaft during rocking, it is possible to efficiently excavate, stir, and mix. Soil cement pillars and soil asphalt cement pillars can be easily formed, and since excavation, stirring, and mixing are performed within the casing, the surrounding ground is not disturbed, and large-diameter soil cement with an accurate shape and uniform strength can be created. The object of the present invention is to provide a method for excavating the ground for forming pillars and soil-asphalt-cement pillars.

The present invention will be explained in detail below with reference to Examples. A in the figure is an excavator used in the ground excavation method of the present invention,
This excavator A includes vertical shaft rotation means 3 for rotating each of a plurality of rotating vertical shafts 1 located on a straight line or on intersecting straight lines or at each apex point of a polygon.
A group driving means 4 is provided for rotating or swinging a group of a plurality of rotary vertical shafts 1 as a unit, and the plurality of rotary vertical shafts 1 are entirely covered with a cylindrical casing K. The casing K may have its upper end fixed to the base B as shown in FIG. 14 so that it does not rotate, or it may rotate. Here, each rotating vertical shaft 1 has a hollow pipe shape, and the inside thereof is used to supply a liquid such as cement milk, a mixture of cement milk and asphalt emulsion, or bentonite. FIGS. 1 and 2 show an example of the vertical axis rotation means 3 and the group drive means 4. FIG. Drive device 5 consisting of power and speed reduction device
and a drive head 6 which is rotated or oscillated by this drive device 5, and the group drive means 4 is constituted by the drive head 6. On the lower surface of the drive head 6, the upper ends of a plurality of rotating vertical shafts 7 are rotatable. The drive head 6 is rotated or swung in the horizontal rotation direction by the drive device 5, so that a group of a plurality of rotating vertical shafts can be rotated or swung in the horizontal rotation direction as a unit. It's getting old. On the other hand, inside the drive head 6, there is provided a rotating device 8 consisting of another power and speed reduction device, and a gear 9 is provided at the upper end of each rotating vertical shaft 1, each meshing with an adjacent gear 9. The rotation of the rotating device 8 is transmitted to one vertical rotating shaft 1, and the rotation of one vertical rotating shaft 1 is transmitted to the other vertical rotating shaft 1 via a gear 9. Therefore, in this embodiment, a rotating device 8, a group of gears 9, etc. are connected to each rotating vertical shaft 1.
It serves as a vertical axis rotation means 3 for rotating the .
In addition, to show an example in which the casing K rotates, as shown in FIG. Supported transmission gear E
is meshed with the central gear D, and the transmission gear E is meshed with the gear train F on the upper inner surface of the casing K, thereby transmitting the rotation of the drive device 5 to the casing K. Here, the casing K rotates but is supported so as not to move vertically relative to the base B. At the lower or central part of each rotating vertical shaft 1 or at the bit 10, there is a spout G for spouting a liquid.
is provided. The liquid is supplied from above one rotating vertical shaft 1, and is connected to the other rotating vertical shaft 1 through a branch pipe H.
It is supplied to the upper end of the Here, the arrangement of each rotational vertical axis 1 is a plurality of them arranged on a straight line as shown in Figs. 3, 4, 7, and 8, or a triangular arrangement as shown in Figs. 5 and 9. The examples shown are those arranged on vertex points and those arranged on orthogonal straight lines as shown in Figs. 6 and 10, but the arrangement is not limited to the above arrangement. It may be located at a corner point, or it may be arranged on each line where a plurality of straight lines other than a cross intersect, or it may be arranged in a manner other than the above. A bit 10 is provided at the lower end of each rotating vertical shaft 1, and each rotating vertical shaft 1 is connected by one or more connecting devices 11, so that the mutual positional relationship of each rotating vertical shaft 1 can be accurately determined. Each rotating vertical shaft 1 is rotatably supported on a coupling device 11. Rotation vertical axis 1
Depending on the application, screw part 12 and stirring blade part 1 are installed.
There is a 3rd class. FIG. 1 shows an example in which a screw portion 12 is provided over the entire length of each rotating vertical shaft 1. FIG. 1 shows an example of a combination of a rotating vertical shaft 1 having screw parts 12 and stirring blade parts 13 alternately in the vertical direction, and a rotating vertical shaft 1 having only the stirring blade parts 13. Here, the stirring blade part 13 of the rotating vertical shaft 1 is the stirring blade part 13 of the adjacent rotating vertical shaft 1.
are slightly shifted in the vertical direction, and the tips of adjacent stirring blades 13 or the trajectories drawn by the tips of the stirring blades 13 overlap each other. Of course, it may be possible to avoid duplication. FIG. 12 shows an example of a combination of a plurality of rotating vertical shafts 1 provided at a plurality of locations with screw portions 12 spaced apart from each other at regular intervals in the vertical direction. In this case, the adjacent rotational vertical axis 1
The screw portions 12 are shifted in the vertical direction so that they are not at the same level. In this embodiment as well, the trajectories drawn by the outer ends of the screw portions 12 of adjacent vertical rotating shafts 1 overlap with each other. Figure 13 shows the stirring blade section 1 in the vertical direction.
An example is shown in which a plurality of rotating vertical shafts 1 are provided at a plurality of locations at regular intervals. In this case, the stirring blades 13 of adjacent vertical rotating shafts 1 are vertically offset, and the trajectories drawn by the tips of the stirring blades 13 overlap each other. Note that although FIGS. 3, 4, 5, and 6 show examples in which the trajectories drawn by the ends of the screw part 12 or the stirring blade part 13 overlap, respectively, FIGS. They may not overlap as shown in FIGS. 9, 9, and 10. Here, the rotation direction of the plurality of rotating vertical shafts 1 can be arbitrarily selected by adjusting the meshing of the gears 9 and the number of gears 9 that transmit rotation. This direction of rotation is illustrated by arrows in FIGS. 3 to 10. The direction of rotation of the plurality of rotating vertical shafts 1 can be determined depending on the purpose of the excavation, for example, by determining the relationship between the excavated soil in the excavation hole and a liquid such as cement milk or a mixture of cement milk and asphalt. The direction of rotation of each shaft may be determined depending on the case where mixing and agitation is the main purpose, or when all or part of the excavated soil is to be discharged to the outside. The figure shows an earth removal window used to discharge excavated earth and sand. Therefore, when excavating the ground 2, the plurality of rotary vertical shafts 1 are individually rotated within the casing K, and the plurality of rotary vertical shafts 1 are rotated as a unit or oscillated in the horizontal rotation direction. The ground 2 is excavated, and the liquid material is spouted from the spout G of each hollow rotating vertical shaft 1. In this case, the ground 2 is excavated within the casing K by each rotating vertical shaft 1, and also by the rotation of a group of plural rotating vertical shafts as a whole, and at the same time, the excavated soil is excavated by each rotating vertical shaft 1. The powder is finely ground by the rotation of the vertical shaft 1, and the powder is ground finely by the rotation of the entire group of rotating vertical shafts. If cement milk or a mixed liquid of cement milk and asphalt is injected into the excavated hole at the same time as the excavation, mixing and agitation of these liquids and the excavated earth and sand will be performed efficiently. Further, when the earth is removed by the screw portion 12, the excavated earth and sand is finely ground, so that the earth can be easily removed.

In the present invention, as described above, the plurality of hollow rotating vertical shafts are entirely covered with a cylindrical casing, and the plurality of rotating vertical shafts are rotated individually, and the plurality of rotating vertical shafts are rotated as a unit. Or, since the ground is excavated by rocking and the liquid is spouted from the hollow rotating vertical shaft, the rotating vertical shaft group in the casing is rotated or rocked as one, and the rotating vertical shaft group is integrally rotated. Or double excavation due to the synergistic effect of the independent rotation of each rotating vertical axis during rocking,
Stirring and mixing are carried out, and large-diameter soil-cement pillars and soil-asphalt-cement pillars can be easily formed in the ground through efficient excavation, stirring, and mixing. Stirring and mixing can be performed uniformly throughout the entire excavation hole, making it possible to form strong soil-cement pillars and soil-asphalt-cement pillars with uniform overall strength and large diameters. This has the advantage of allowing accurate excavation without damaging the surrounding ground. Further, since the group of rotating vertical shafts rotates or swings as a unit within the casing, there is an advantage that the group of rotating vertical shafts can smoothly rotate or swing as a unit without receiving large resistance from the surrounding ground. If excavated continuously, thick soil-cement walls and soil-asphalt-cement walls can be formed. Furthermore, if the casing is made removable, a large diameter casing can be driven in by pulling up the excavator while leaving the casing in the ground.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway front view showing an example of an excavator used in the present invention, and Fig. 2 a and b are Fig. 1 X-X.
Figure 1 is a cross-sectional view along the Y-Y line, Figures 3 to 10 are schematic cross-sectional views showing the arrangement of the shafts of the above, and Figures 11 to 13 are schematic cross-sectional views of the same excavator. FIG. 14 is a front view of each embodiment in which a screw part and a stirring blade part are provided on the rotating vertical shaft, and FIG. The shaft, 2 is the ground, and K is the casing.

Claims (1)

[Claims] 1 Encasing the entire plurality of hollow rotating vertical shafts in a cylindrical casing, excavating the ground by rotating each of the plurality of rotating vertical shafts and rotating or swinging the plurality of rotating vertical shafts as a unit. A ground excavation method characterized in that a liquid material is ejected from a hollow rotating vertical shaft to form a mixture of soil and liquid material.