JP3879737B2 - Ground improvement single axis convection mixing stirrer with ring - Google Patents

Description

  The present invention relates to a ground improvement single-axis convection mixing and stirring device having a ring, and more particularly to a ground improvement single-axis convection mixing and stirring device used in a method of forming a pile on the ground and improving the ground.

When building a structure by improving the ground in a place where the strength of the ground such as soft ground or landfill is relatively weak, there is a method of driving piles made of concrete etc., but due to noise problems etc. Being shunned.
On the other hand, instead of the construction method, a method of excavating a hole in the ground, injecting an injection material (solidifying material) called cement, a coagulant or a hardener into the excavated soil, and forming a pile by mixing and stirring (place) The pile construction method is being carried out.
Conventionally, a base machine or the like is used for excavating the hole, and a plurality of stirring bodies such as a plurality of stirring rods are projected in a direction perpendicular to the axis in the vertical direction of a single axis (single axis) rotation axis (stirring axis). The agitator such as a plurality of stirring rods is rotated integrally with the rotation of the rotary shaft, and the hardener is injected as described above while jetting the hardener. Is used to stir knead and improve the ground by curing.
The rotating shaft for stirring is composed of a double shaft of an outer shaft and an inner shaft rotating in opposite directions, and a stirring blade is attached to each of the inner and outer shafts, and they are rotated in the opposite directions on the inner and outer sides. A ground improvement device has also been proposed (Japanese Patent Publication No. 3-40166). In addition, examples of patents related to the related ground improvement device include JP-A-1-17917, JP-A-6-193047, JP-A-6-193059, and JP-A-10-159083. There is a publication.
However, a plurality of stirrers such as a plurality of stirrers are projected in a direction perpendicular to the axis in the vertical direction of the conventional single-axis rotation shaft described above, and the plurality of stirrers such as the stirrer bars are attached to the rotation shaft. In the ground improvement device that rotates together with the rotation, all of the plurality of stirring rods rotate integrally with the rotation shaft, so that a so-called co-rotation phenomenon occurs in which the excavated soil rotates integrally with the coaxial shaft. When the hardener is difficult to knead, especially when the ground is made of viscous soil, the excavated soil will be in a dumpling state that wraps the stir bar, and stirring and kneading cannot be performed at all. There was a drawback that there was.
Further, in the ground improvement device configured as the above-mentioned inner and outer double shafts, a stirring body such as a plurality of stirring rods is projected in a direction perpendicular to the rotation shaft, and the stirring rotation in the horizontal direction is performed with respect to the rotation shaft. Therefore, if the entire stirring device is not moved up and down in the ground, the ground cannot be sufficiently stirred in the vertical direction (depth direction). In order to reduce the length of the stirring device, it is necessary to increase the length of the stirring device in the vertical direction, and in the case of horizontal stirring, the rotating shafts for stirring are rotated in opposite directions and sheared. Even if the force is improved, it cannot be utilized, the shearing force is weak, the excavation speed is slow, the stirring and kneading tends to be insufficient, and the effect of preventing the co-rotation phenomenon and excavation soil dumping There were still cases where it was insufficient
Therefore, the present inventor performs excavation by rotating a plurality of spiral stirrers in different rotation directions in the ground improvement device configured on the inner and outer double shafts, and causes convection agitation during the excavation. The ground improvement device is proposed, and by this device, the curing agent is diffused by the convection and the stirring and kneading efficiency is high, and sufficient vertical movement can be achieved without moving the ground in the vertical direction. It is possible to ensure good ground improvement by ensuring stirring in the direction, and further, since convective stirring is performed, the length in the vertical direction of the stirring device is sufficient, and the device can be downsized. (Japanese Patent Laid-Open No. 2000-345555).
However, in the ground improvement device configured on the double shaft, an internal / external double pipe is required, and a rotary transmission shaft is required to reversely rotate the double pipe mutually, and a dedicated machine is required for that purpose. However, there are disadvantages such as being expensive, determining the number of revolutions, the ratio of the number of revolutions inside and outside, and being difficult to assemble and disassemble.
JP 3-40166, JP 1-17917, JP 6-193047, JP 6-193059, JP 10-159083, JP 1-113116, JP 58-29374, JP-A-3-212512, JP-A-4-289319, JP-A-6-26032, JP-A-7-109729, JP-A-2000-345555.

The object of the present invention is to provide a technique capable of eliminating the drawbacks of the prior art.
Other objects and novel features of the present invention will become apparent from the description of the present specification and the drawings.

The claims of the present invention are as follows.
(Claim 1) In a mixing stirrer used in a construction method for excavating the ground while rotating a drilling member, mixing excavated soil and solidified material to form a pile in the ground and improving the ground, Attach a stirring member to the stirring shaft, one of which pushes up the excavated soil and the other pushes down the excavated soil, and attaches an outer rod to the excavating shaft, attaches a drum to the outer rod, and causes convection stirring in the ground of the excavated soil A ground improvement single shaft having a ring, wherein a mounting member is attached to the outer rod, and a member for stopping rotation of the drum having a ring is attached to an end of the mounting member. Convection mixing and stirring device (Claim 2) A member for stopping rotation of a drum having a ring is attached to a joint portion between an arm portion of the drum rotation stopping member and an end portion of the attachment member via a pin. Special To, uniaxial convective mixing and stirring apparatus of ground improvement having a ring according to claim 1.

    According to the present invention, the curing agent is diffused by the convection by the convection stirring, the stirring and kneading efficiency is high, and sufficient stirring in the vertical direction is ensured even if the apparatus is not moved much in the vertical direction in the ground. In addition to having the advantage that the apparatus can be reduced in size, and having the advantage that the apparatus can be reduced in size, it is possible to provide a ground improvement apparatus using a single stirring shaft with convection stirring. In the ground improvement device constructed with a double shaft, an internal / external double pipe is required, a rotary transmission shaft is required to reversely rotate the double pipe, and a dedicated machine is required for that purpose. In addition, it has been possible to eliminate disadvantages such as being expensive, the ratio of the internal and external rotational speeds becoming a problem when determining the rotational speed, and being difficult to assemble and disassemble.

  Next, embodiments of the present invention will be described with reference to the drawings.

Example 1.
Embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 1, two stirring members 2A and 2B are attached to a single stirring shaft (rotary shaft, excavation shaft) 1 in a single shaft convection stirring device Y for ground improvement.
The stirring member 2B is directly attached to the stirring shaft 1.
An outer rod 3 is attached to the stirring shaft 1.
A drum 4 is attached to the outer rod 3.
The stirring member 2B is positioned inside the drum 4. The middle stirring member 2B (hereinafter sometimes referred to as the middle blade 2B) is wound around the stirring shaft 1 in a spiral shape.
The lower part of the stirring member 2 </ b> A is connected to the excavation blade 5, and the upper end of the stirring member 2 </ b> A is connected to the connecting ring 6.
As shown in FIG. 2, the stirring member 2A includes two spiral component members 2A-1 and a spiral component member 2A-2, and the spiral component member 2A-1 and the spiral member The component member 2A-2 is arranged in a mirror shape (symmetrically) with the stirring shaft 1 as a center, and the spiral component member 2A-1 and the spiral component member 2A-2 are arranged in the drum. 4 is located outside. The outer stirring member 2A (hereinafter also referred to as the outer blade 2A) is configured to push up the excavated soil in the rotational direction as shown in the figure.
On the other hand, the middle blade 2B is a stirring member that pushes the excavated soil in the rotation direction with respect to the outer blade 2A.
In FIG. 2, the drum 4 is omitted in order to make the outer blade 2 </ b> A and the middle blade 2 </ b> B easier to see, and in order to deepen the understanding, it is enlarged as compared with FIG. 1. It is shown.
From the winding form, the outer blade 2A and the middle blade 2B are reversely wound with respect to the normal winding of the outer blade 2A.
The middle blade 2B is attached to the stirring shaft 1, and rotates in the same direction as the stirring shaft 1 rotates.
Since the lower end of the outer blade 2A is attached to the excavation blade 5, and the excavation blade 5 is attached to the stirring shaft 1, the outer blade 2A moves in the same direction as the stirring shaft 1 rotates. Rotate. Since the connecting ring 6 (hereinafter also referred to as the outer blade connecting ring) 6 of the outer blade 2A is provided on the outer periphery of the drum 4 so as to be separated from the drum 4, the outer blade 2A As the stirring shaft 1 rotates, it rotates in the same direction as the middle blade 2B.

As described above, the drum 4 is attached to the outer rod 3 by the drum attachment member 400, and the outer rod 3 is provided around the stirring shaft 1, so that the stirring shaft 1 rotates. Accordingly, the drum 4 rotates and rotates, so that the drum 4 also rotates and rotates as the stirring shaft 1 rotates.
As shown in FIG. 4, a member for attaching the attachment member 7 to the outer rod 3 and stopping the rotation of the drum having a cylindrical ring at the end of the attachment member 7 (hereinafter referred to as a drum rotation stop member). There is also 8).
As shown in FIG. 4, a pin (rotary shaft, shaft pin) 9 is interposed at the joint between the end of the attachment member 7 of the drum rotation stop member and the arm portion 800 of the drum rotation stop member 8. The attachment member 7 is attached to the outer rod 3, and the drum rotation stop member 8 is attached to the end of the attachment member 7.
As shown also in FIG. 4, the drum rotation stop member 8 has a cylindrical ring 801.
As described above, the outer rod 3 rotates and rotates with the rotation of the stirring shaft 1, and the drum 4 rotates and rotates with the rotation of the stirring shaft 1. The drum rotation stop member 8 having the ring-shaped ring 801 can prevent the drum 4 from rotating.

As shown in FIG. 5, the outer rod 3 and the attachment member 7 of the drum rotation stop member 8 rotate in the same direction as the excavation shaft 1 rotates, but the attachment member 7 of the drum rotation stop member 8 and the drum rotation stop member Since the pin (rotating shaft, shaft pin) 9 is interposed at the joint portion with the arm portion 800, the arm portion 800 of the drum rotation stop member 8 includes the excavation shaft 1, the outer rod 3, and the drum. The rotation of the attachment member 7 of the rotation stop member 8 is not affected by the rotation of the attachment member 7 in the ground, and the rotation of the drum 4 can be stopped by stopping the rotation.
To explain the operation of the co-rotation preventing member 8 having the ring (cylindrical portion) 801 based on FIG. 5, the outer rod 3 and the stirring shaft 1 are usually idle at the rotation center A. If the rotation center starts to rotate with the drum 4, the center of rotation shifts from A to the rotation center B of the rotation shaft (pin) 9, and the ring 801 tries to rotate as shown in the figure. The ring 801 cannot be rotated to some extent by being held down by the earth pressure of the surrounding soil 10, and eventually the center of rotation returns to A.
As a result, the rotation of the ring 801 is stopped and the rotation of the drum 4 is also prevented. The drum 4 is fixed even if the stirring shaft 1 rotates.
Even if the ring 801 is a relatively soft ground or a relatively hard ground, the ring 801 is not rotated and the rotation center is shifted as described above, and the rotation prevention effect of the fixed drum 4 is achieved. Play.

For example, as shown in FIG. 6, the ground improvement device Y has a stirring shaft 1 attached to a lower part of a drive motor 12 of a movable base machine 11, and is rotated by the rotation of the single-shaft stirring shaft 1. When the blade 2A and the middle blade 2B are rotated in the same direction, the fixed drum 4 is fixed, and the middle blade 2B is rotated inside the fixed drum 4, the middle blade 2B is rotated in the rotation direction of the stirring shaft 1 On the other hand, the outer blade 2A functions to push up the excavated soil with respect to the rotation direction of the agitating shaft 1 to convect and agitate the excavated soil, Along with the excavation, the excavation progresses, a circular columnar excavation hole perpendicular to the ground is excavated, and a solidified material (hardening agent) is jetted from the discharge port 13 via the inside of the stirring shaft 1, The excavated soil is agitated and kneaded to form a ground improvement part in the excavation hole. It can be improved ground.
As shown in FIG. 3, when the middle blade 2B rotates inside the fixed drum 4 and the outer blade 2A rotates outside the fixed drum 4, convection agitation occurs. Since the kneading with the solidified material from the discharge port 13 and the kneading with the solidified material from the discharge port 13 outside the fixed drum 4 are performed interchangeably, and then the kneading is performed throughout, an excellent curing agent And stirring and mixing can be performed.
In this apparatus, generally, the right rotation of the stirring shaft 1 advances excavation, and the left rotation is pulling up the apparatus. Due to the difference in the rotation direction, the direction of convection for pushing up and pushing down the excavated soil is also reversed. become.

Example 2
Next, a second embodiment of the present invention will be described based on FIG. 7, FIG. 8, FIG. 9, and FIG.
In this embodiment, instead of the cylindrical ring 801, an arcuate ring 802 is used, and the semicircular ring 802 is an upper center portion of a circular ground excavation hole (excavation wall surface) 10. From the left end of the excavation hole 10 in the circular ground, it is installed in an arcuate shape inside it.
The arcuate ring 802 of the drum rotation stop member 8 is connected to the outer rod 3 via the end of the attachment member 7 of the drum rotation stop member and the pin (rotary shaft, shaft pin) 9 as in the above embodiment. The outer rod 3 rotates and rotates as the stirring shaft 1 rotates, and the drum 4 rotates and rotates as the stirring shaft 1 rotates. The drum rotation stop member 8 having the ring 802 can prevent the rotation of the drum 4 in the same manner as the drum rotation stop member 8 having the cylindrical ring 801 described above. When the fixed drum 4 rotates together with the middle blade 2B and the outer blade 2A, the convective stirring cannot be caused.
In the case of a relatively soft ground, as shown in FIG. 8, the ring 802 having an arcuate shape of the drum rotation stop member 8 moves, and a part of the ring 802 is bitten into the ground 10, so that the drum 4 is 3 and the middle blade 2 </ b> B can be rotated on the inside of the fixed drum 4. When the fixed drum 4 rotates together with the middle blade 2B and the outer blade 2A, the convective stirring cannot be caused but can be prevented.
On the other hand, the operation of the semicircular ring 802 when the ground is relatively hard will be described with reference to FIG.
When the ground is relatively hard, as shown in FIG. 9, the bow-shaped ring 802 of the drum rotation stopping member 8 swings (slides) the wall surface 10 of the ground, stops its rotation, and is fixed. It is possible to prevent the drum 4 from rotating. When the fixed drum 4 rotates together with the middle blade 2B and the outer blade 2A, the convective stirring cannot be caused but can be prevented.
FIG. 10 shows the movement of the arcuate ring 802 of the drum rotation stop member 8 in both hard and soft ground.

Example 3
Next, a third embodiment of the present invention will be described with reference to FIG.
In the third embodiment, the arcuate ring 802 of the drum rotation stop member 8 of the second embodiment is formed in a bow shape from the upper center portion to the lower center portion of the excavation hole 10 of the circular ground. Although the points are the same, as shown in FIG. 11, the left end of the circular ground excavation hole 10 is not separated from the left end of the excavation hole 10 of the circular ground as in the second embodiment. An example is shown in the form of following.
To explain the operation of the arcuate ring 803 of the drum rotation stop member 8 of the third embodiment, as described above, the attachment member 7 of the drum rotation stop member rotates in the same direction as the excavation shaft 1 rotates. However, the arm portion 800 of the arcuate ring 803 of the drum rotation stop member 8 can move freely around the rotation axis 9 without being affected by the movement of the attachment member 7 of the drum rotation stop member. The arcuate ring 803 at the tip of the rotation stop member 8 can also move freely. As a result, for example, in the case of a relatively soft ground, as shown in FIG. The ring 803 at the tip of the ring moves, and a part of the ring 803 is caught in the excavation hole 10 in the ground, so that the drum rotation stop member 8 can avoid the rotation of the fixed drum 4. That.
On the other hand, even when the ground is relatively hard, the ring 803 of the drum rotation stopping member 8 can slide on the wall surface 10 of the ground and avoid the rotation of the fixed drum 4.
Since the ring 803 of the drum rotation stop member 8 of the third embodiment is in comparison with the ring 802 of the drum rotation stop member 8 of the second embodiment, the ring 803 is along the excavation hole 10 of the circular ground. As shown in the figure, at both ends of the ring 803, the ratio of rocking along the ground wall (sliding along the ground wall) is large.

  The solidifying material used in the present invention can be used regardless of the name of cement, coagulant, solidifying material, curing agent, etc., as long as it meets the purpose. Specific examples of the solidifying material Examples thereof include cement milk and sodium silicate.

The present invention can be modified as appropriate. For example, a linear member instead of the ring of the above embodiment, a mountain-shaped member, or the like can be modified as appropriate. Other things can be applied as long as they function.
The rotating shaft in the present invention may be other as long as it performs the same function.

  INDUSTRIAL APPLICABILITY The present invention can be applied to all methods of excavating the ground while rotating excavating members, mixing excavated soil and solidified material to form piles in the ground, and improving the ground.

It is a block diagram of the uniaxial convection mixing and stirring apparatus of the ground improvement which shows the Example of this invention. It is explanatory drawing of the outer blade | wing and middle blade | wing in the uniaxial mixing and stirring apparatus of the ground improvement which shows the Example of this invention. It is explanatory drawing of the convection stirring by the uniaxial mixing stirring apparatus of the ground improvement which shows the Example of this invention. It is explanatory drawing of the drum rotation stop member in the uniaxial mixing and stirring apparatus of the ground improvement which shows the Example of this invention. It is explanatory drawing explaining an example of operation | movement of the drum rotation stop member in the uniaxial mixing and stirring apparatus of the ground improvement which shows the Example of this invention. It is explanatory drawing explaining an example of the application example of the uniaxial mixing and stirring apparatus of the ground improvement which shows the Example of this invention. It is explanatory drawing of the drum rotation stop member in the uniaxial mixing and stirring apparatus of the ground improvement which shows the other Example of this invention. It is operation | movement explanatory drawing of the drum rotation stop member. It is operation | movement explanatory drawing of the drum rotation stop member. It is operation | movement explanatory drawing of the drum rotation stop member. (A) is explanatory drawing of the drum rotation stop member in the uniaxial mixing and stirring apparatus of the ground improvement which shows further another Example of this invention, (B) is operation | movement explanatory drawing of the drum rotation stop member.

Explanation of symbols

1 Stirring shaft 2A Stirring member 2B Stirring member 3 Outer rod 4 Drum (fixed drum)
5 Excavation blade 6 Connection ring 7 Drum rotation stop member mounting member 8 Drum rotation stop member 9 Pin (rotary shaft, shaft pin)
10 Ground wall 1
DESCRIPTION OF SYMBOLS 11 Base machine 12 Drive motor 13 Solidification material discharge port 801 Ring 802 Ring 803 Ring Y Single-axis convection stirring apparatus of ground improvement

Claims (2)

In the mixing stirrer used in the construction method to excavate the ground while rotating the excavating member, mix the excavated soil and solidified material to form a pile in the ground and improve the ground, Attach the agitating member that pushes up the excavated soil and pushes down the excavated soil, attaches an outer rod to the excavating shaft, attaches a drum to the outer rod, and causes convection agitation in the ground of the excavated soil A ground-improved single-axis convection mixing and stirring apparatus having a ring, wherein a mounting member is attached to the outer rod, and a member for stopping the rotation of the drum having a ring is attached to an end of the mounting member. The member for stopping the rotation of the drum having the ring is attached to a joint portion between the arm portion of the drum rotation stopping member and the end portion of the mounting member via a pin, and is characterized in that A ground improved single-axis convection mixing and stirring device having the ring described above.

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