JP2015227573A - Ground excavation mixing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ground excavation mixing device easy in maintenance, for efficiently executing site preparation of a columnar improvement body in a short time, by sufficiently agitating excavation soil wetted with cement milk, by exhibiting high propulsive power when excavating the ground.SOLUTION: A ground excavation mixing device 1 is integrally constituted by assembling a pipe body 2, drilling blades 3 and 3, first mixing blades 5 and 5, corotation prevention blades 6 and 6, second mixing blades 7 and 7, and a drilling body 8. The tip of the pipe body 2 is provided with a discharge pipe 4 being a discharge port for discharging cement milk of flowing down in the pipe body 2. The lower side of its discharge pipe 4 is provided with a cross-sectional semicylindrical dispersion member 9 for laterally dispersing the cement milk discharged from the discharge pipe 4.

Description

  The present invention relates to a ground excavation mixing device used for excavating ground in ground improvement work and mixing current soil and cement milk.

  As a method for improving soft ground to solid ground, excavated soil that has been solidified by pouring cement milk or the like while excavating the ground into a cylindrical shape with a predetermined depth, stirring, mixing, and moistening with the cement milk A method is known in which a columnar improvement body is formed by solidifying slag. In addition, as a ground excavation mixing device used for the construction work of such a columnar improvement body, two rod-shaped excavation blades each having an excavation claw attached to the tip of the pipe main body are aligned in a radial direction from the outer periphery of the pipe main body. Two bar-shaped stirring blades are provided on the upper side of the excavating blades so as to protrude in a straight line from the outer periphery of the tube main body and discharge the cement milk. What provided the exit in the base end of a pair of excavation blade is known (patent document 1).

JP 2001-323455 A

  However, in the conventional ground excavation and mixing device, since the cement milk only flows downward from the tip of the pipe body, the cement milk does not diffuse widely in the ground near the tip of the pipe body. The ground cannot be softened sufficiently. Therefore, the soil mass cannot be finely crushed, the uniformity of the improved columnar improvement body becomes low, and the excavation blades cannot generate high propulsive force when excavating the ground, so the columnar shape The construction work of the improved body cannot be performed efficiently. In addition, there is a problem that the excavation claw is easily damaged and the excavation claw must be replaced within a short period of time.

  The object of the present invention is to solve the problems of the conventional ground excavation mixing device, exhibit high driving force when excavating the ground, can sufficiently agitate the excavated soil wet with cement milk, An object of the present invention is to provide a ground excavation and mixing device that can efficiently perform the construction work of a columnar improvement body in a short time and is easy to maintain.

  Among the present inventions, the invention described in claim 1 is characterized in that a cemented milk is allowed to flow down and a long drilling body is provided with a sharpened excavating body facing downward, and the distal end of the pipe body. In this case, a long excavation blade having a plurality of excavation claws protruding downward is provided so as to protrude radially from the outer periphery of the pipe body, and a long shape is provided above the excavation blade. The co-rotation prevention wing is provided so as to protrude radially from the outer periphery of the tube body and to be rotatable with respect to the tube body, and is long above or below the co-rotation prevention wing. A ground excavating and mixing device provided so that the mixing blade in the shape of the tube protrudes radially from the outer periphery of the tube body, for discharging the cement milk flowing down the inside of the tube body to the tip of the tube body A discharge port is provided and below the discharge port. It is characterized in that the cross-sectional semi-tubular dispersion member for dispersing the cement milk discharged from the outlet to the left and right are provided.

  The invention described in claim 2 is the invention described in claim 1, wherein the excavation body is a belt-like one whose center is bent in a downward V shape, and both ends are fixed to the outer periphery of the pipe body. In addition, the excavator supports the lower side of the central portion of the dispersion member.

  The invention described in claim 3 is characterized in that, in the invention described in claim 1 or 2, the dispersion member is provided substantially parallel to the excavation blade.

  The ground excavation and mixing device according to claim 1 is capable of widely diffusing cement milk flowing down from the discharge port of the pipe body to the ground near the tip of the pipe body by the dispersing member and softening the ground. In addition to efficiently excavating the ground, the mass can be crushed finely by the mixing blade, and a highly uniform and high strength columnar improved body can be efficiently created within a short time. In addition, maintenance is easy because the excavation claws are not easily damaged.

  In the ground excavation mixing apparatus according to claim 2, since the lower side of the central portion of the dispersion member is covered by the excavation body, the dispersion member is hardly damaged and cement milk is diffused over a long period of time. Function can be demonstrated. Moreover, since the upper surface of the dispersing member is in an open state, when the inside of the dispersing member is clogged with soil, the situation can be easily solved.

  In the ground excavation mixing apparatus according to claim 3, since the dispersion member is provided substantially parallel to the excavation blade, the dispersion member hardly breaks because the dispersion member hardly collides with hard debris in the ground. It is difficult to exert a function of excavating and mixing the ground over a long period of time.

It is a front view of a ground excavation mixing device. It is a right view of a ground excavation mixing apparatus. It is a perspective view of a ground excavation mixing device. It is the perspective view (a) and front view (b) of a supporting member.

  Hereinafter, a ground excavation mixing apparatus according to the present invention will be described in detail with reference to the drawings. 1 to 3 are a front view, a right side view, and a perspective view of the ground excavation mixing device, respectively. The ground excavation mixing device 1 includes a pipe body 2, excavation blades 3, 3, co-rotation preventing blades 6, 6, first mixing blades 5, 5 and second mixing blades 7, 7 functioning as mixing blades, excavation body 8, It is configured integrally by assembling the dispersion member 9 and the like.

  The tube body 2 is formed of a steel having a thickness of about 20 mm into a long hollow cylindrical shape having a length of about 615 mm and a diameter (outer diameter) of about 139.8 mm. Further, a tapered portion is provided on the upper side of the tube body 2 so that the diameter gradually increases from the lower side to the upper side, and a flat cylindrical large-diameter portion having a constant diameter is provided on the upper side of the tapered portion. It has been. The proximal end is provided with a thick cylindrical coupling portion 10 having a length of about 200 mm for coupling to an excavating machine (not shown). On the other hand, a bottom plate (not shown) is welded to the tip of the tube body 2 and has a diameter (outer diameter) of about 60.5 mm that functions as a discharge port for discharging cement milk from the center of the bottom plate. A cylindrical discharge pipe 4 protrudes downward.

  Further, an excavation body 8 is provided at the lower end of the pipe body 2. The excavated body 8 is formed of a cemented carbide in a substantially band shape having a predetermined width (left and right width of about 48 mm), and the center portion is bent in a downward V shape and has a pointed state (inverted conical shape). ing. A surface near the center (an inverted conical surface) is inclined downward at a predetermined angle (about 30 °) from the outside to the center. On the other hand, the inner surface of the central portion is in a state of being curved in an arc shape. The excavated body 8 is fixed to the distal end of the pipe body 2 by welding the outer circumferences of both ends with the inner sides of both ends in contact with the outer circumference of the pipe body 2.

  On the other hand, the dispersion member 9 is formed in a semi-cylindrical shape having a curvature radius (inner radius of curvature) of about 200 mm and a length of about 35 mm by bending a steel plate having a thickness of about 4.5 mm. (Thus, the front and rear inner width is about 70 mm). The dispersion member 9 is fixed to the excavation body 8 by welding in a state where the outer surface of the central portion is in contact with the inner surface of the central portion of the excavation body 8, and each of the left and right portions of about 76 mm are excavated. The body 8 is exposed.

  Further, support members 13 and 13 are fixed to the lower left and right sides of the dispersion member 9. FIG. 4 shows the support member 13, and each support member 13, 13 is formed by cutting a steel plate having a thickness of about 6.2 mm, so that a substantially triangular shape (to be exact, at the end of the triangle). It is formed in a plate shape (flat, substantially triangular prism shape) that is slightly cut off, and the lower surface is inclined downward at a predetermined angle (about 20 °) from the outside to the center. The support members 13, 13 are welded to the dispersing member 9 and the excavating body 8 by welding the horizontal upper surface to the lower surfaces of the left and right protruding portions of the dispersing member 9 and welding the vertical side surface to the side surface of the excavating body 8. The left and right protruding portions of the dispersion member 9 are supported from below. Note that the outer end portions (rectangular portions) of the support members 13 and 13 are flush with the side surfaces of the dispersion member 9.

  Further, two excavation blades 3 and 3 are fixed by welding so as to protrude from the center of the pipe body 2 to the left and right at the end of the pipe body 2 and above the welded portion of the excavation body 8. . Each of the excavating blades 3 and 3 is formed by a steel plate having a thickness of about 6.2 mm into a substantially rectangular shape with left and right lengths × front and back lengths = about 232 mm × about 232 mm. It is fixed in an inclined state of + 45 ° and −45 ° with respect to the axial direction of 2. Further, the lower ends of the excavating blades 3 and 3 are arranged in parallel to the dispersion member 9 with a distance of about 39 mm (distance in the vertical direction). Then, at the edge of the lower end of each of the excavating blades 3, 3, two excavating claws 11, 11 having a quadrangular prism shape and sharpened at the tip are parallel to each other at a predetermined angle and the longitudinal length of the excavating blade 3 It is provided so as to be orthogonal to the direction, and protrudes from the lower end of each excavation blade 3, 3 by about 70 mm.

  In addition, the first mixing blades 5 and 5 are provided above the excavation blades 3 and 3 at a distance of about 34 mm (interval in the vertical direction) so as to protrude from the center of the pipe body 2 to the left and right. Yes. Each of the first mixing blades 5 and 5 is formed in a horizontally long rectangular plate shape by a steel plate having a thickness of about 24 mm, and has a length of about 228 mm in the front-rear direction and a width (left and right) of about 78 mm. ing. And it is adhering (welding) to the pipe main body 2 in a state where the plate surface is horizontal so as to be orthogonal to the respective excavation blades 3 and 3 and the pipe main body 2.

  Further, above the first mixing blades 5 and 5 separated by a distance of about 146 mm (interval in the vertical direction), the co-rotation preventing blades 6 and 6 protrude left and right from the center of the tube body 2. And it is provided rotatably. The co-rotation preventing wings 6 and 6 are each a rotary support body in which a rectangular steel plate having a thickness of about 48 mm and a lateral length of about 260 mm × a height of about 98 mm is provided to be rotatable with respect to the tube body 2. 12 is formed by screwing with a bolt and a nut. The width of the co-rotation preventing blades 6 and 6 (the width including the rotary support 12, that is, the protruding length in the radial direction from the center of the tube body 2) is the excavation blades 3 and 3, the first mixing blades 5 and 5. 5. It is longer than the second mixing blades 7,7. Moreover, in order to improve the co-rotation prevention efficiency (increase the resistance received from soil) with the first mixing blades 5 and 5 and the second mixing blades 7 and 7, It is formed wider than the other parts (wide in the vertical direction).

  In addition, the second mixing blades 7, 7 protrude from the center of the tube body 2 to the left and right above the common rotation prevention blades 6, 6 separated by a distance of about 106 mm (interval in the vertical direction). Is provided. Each of the second mixing blades 7 and 7 is formed in a horizontally long rectangular plate shape by a steel plate having a thickness of about 24 mm, like the first mixing blades 5 and 5, and has a lateral length of about 208 mm × width. It has a size of about 78 mm (front and rear). And, it is fixed (welded) to the pipe body 2 in a state where the plate surface is horizontal so as to be orthogonal to the first mixing blades 5 and 5 and the pipe body 2 and parallel to the excavation blades 3 and 3.

[How to use ground excavation mixing equipment]
The ground excavation mixing apparatus 1 configured as described above can be suitably used for the construction work of a columnar improvement body on soft ground. When carrying out the construction work of the columnar improvement body using the ground excavation mixing device 1, the ground excavation mixing device 1 is pushed against the ground and pressed into the ground while applying pressure to rotate the pipe body 2. Moreover, with this rotation, cement milk is pressed into the inside of the pipe body 2 from above and discharged from the discharge port (discharge pipe 4) to the outside.

  When the pipe body 2 is rotated as described above, the ground is excavated with high propulsive force by the excavating body 8 and the excavating blades 3 and 3 fixed to the tip of the pipe main body 2. In addition, as the pipe body 2 rotates, the current soil (excavated) moistened with cement milk by the excavating blades 3, 3, the first mixing blades 5, 5, and the second mixing blades 7, 7 fixed to the pipe body 2. Earth) is efficiently mixed and stirred. The co-rotation preventing blades 6 and 6 are inclined with respect to the vertical direction in order to maintain a state in which they do not rotate (or a state rotated at a rotational speed slower than the rotational speed of the tube body 2) regardless of the rotation of the tube body 2. Effectively prevent excavation in the specified direction. Further, the soil is finely pulverized by generating an appropriate share due to the rotational speed difference between the excavating blades 3, 3, the first mixing blades 5, 5, the second mixing blades 7, 7 and the co-rotation preventing blades 6, 6. It becomes possible. Therefore, it is possible to form a linear and uniform columnar improvement body (here, a columnar improvement body that is accurately oriented vertically downward) with an accurate axis.

  Then, after rotating the tube body 2 to a sufficient depth and standing up and forming a columnar soil moistened with cement milk, the tube body 2 is pulled out while rotating in a reverse direction and allowed to cure for a sufficient amount of time. To solidify the cement milk.

[Effect of ground excavation mixing device]
As described above, the ground excavation mixing apparatus 1 is provided with a discharge port (discharge tube 4) for discharging cement milk flowing down in the pipe body 2 at the tip of the pipe body 2, and the discharge port. A dispersion member 9 having a semi-cylindrical cross section for dispersing the cement milk discharged from the discharge port to the left and right is provided on the lower side. Therefore, the cement milk flowing down from the discharge port can be widely diffused to the ground near the tip of the pipe body 2 by the dispersing member 9, and the ground can be softened. Therefore, the ground can be efficiently excavated with high thrust. In addition, the clot is finely crushed by the mixing blades (first mixing blades 5, 5 and second mixing blades 7, 7), and a columnar improved body having high uniformity and high strength is efficiently formed within a short time. be able to. In addition, since the excavation claws 11 and 11 are hardly damaged, maintenance is easy.

  Moreover, the ground excavation mixing apparatus 1 is a substantially strip-shaped excavation body 8 whose center is bent in a downward V-shape, and both ends are fixed to the outer periphery of the pipe body 2 and the excavation body 8. Thus, since the lower side of the central portion of the dispersion member 9 is supported (supported), the dispersion member 9 is not easily damaged, and the function of diffusing cement milk over a long period of time can be exhibited. Moreover, since the upper surface of the dispersion member 9 is in an open state, when the inside of the dispersion member 9 is clogged with soil, the situation can be easily solved.

  Further, in the ground excavation mixing apparatus 1, since the dispersion member 9 is provided substantially parallel to the excavation blades 3 and 3, it is difficult for the dispersion member 9 to collide with hard debris in the ground. 9 is hard to break and can exhibit the excavation and mixing function of the ground for a long period of time.

  In addition, since the dispersion member 9 is supported by the support members 13 and 13 in the ground excavation mixing apparatus 1, the dispersion member 9 is not broken even when it collides with hard debris in the ground. There is no need to replace it, and maintenance is easy. Moreover, since the substantially strip-shaped excavation body 8 and the support members 13 and 13 are orthogonal to each other at the distal end portion of the pipe body 2 and have a shape like a plus driver, excavation of the ground when the pipe body 2 is rotated is performed. Efficiency and mixing efficiency are very good.

[Change example of ground excavation mixing equipment]
In addition, the structure of the ground excavation mixing apparatus according to the present invention is not limited to the aspect of the above embodiment, and the pipe body, excavation body, excavation blade, co-rotation prevention blade, mixing blade (first mixing blade, The composition of the material, shape, structure and the like of the second mixing blade) and the dispersing means can be appropriately changed as necessary without departing from the gist of the present invention.

  For example, the ground excavation mixing device according to the present invention is not limited to the one provided with two types of mixing blades, the first mixing blade and the second mixing blade, as in the above embodiment, but one type or three or more types of mixing blades It is also possible to change to those with wings. Further, the ground excavation mixing device is not limited to the one in which the left and right excavation blades each have two excavation claws as in the above-described embodiment, and one or three or more excavation blades on the left and right are excavated. It is also possible to change to one having a nail. Further, the co-rotation preventing wing is not limited to the one in which the left and right tips are formed wider than the other portions as in the above embodiment, and the width at the left and right tips may be substantially the same as the other portions. . In addition, the co-rotation preventing wings are not limited to those projecting radially from the center of the tube main body to the left and right, but may be three or more projecting radially from the center of the tube main body at equal angular intervals.

  Since the ground excavation mixing apparatus of the present invention has excellent effects as described above, it can be suitably used as an apparatus for constructing a columnar improvement body.

1 .... ground excavation mixing device 2 .... pipe body 3 .... excavation blade 4 .... discharge pipe (discharge port)
5. First mixing blade (mixing blade)
6. ・ Co-rotating blade 7 ・ ・ Second mixing blade (mixing blade)
8. Drilling body 9. Dispersing member

Claims (3)

A long drilling body with a sharp pointed tip is provided at the end of a long tube body that can flow cement milk, and a plurality of drilling claws project downward at the tip of the tube body A long excavation blade is provided in the radial direction from the outer periphery of the tube body. The long mixing blade protrudes radially from the outer periphery of the tube body above or below the co-rotation prevention blade. A ground excavation mixing device provided to perform,
At the tip of the pipe body, a discharge port is provided for discharging cement milk flowing down inside the pipe body, and the cement milk discharged from the discharge port is distributed to the left and right below the discharge port. A ground excavation and mixing device, wherein a dispersion member having a semi-cylindrical cross section is provided.   The excavation body is a belt-like one whose center is bent in a downward V shape, and both ends are fixed to the outer periphery of the pipe body, and the excavation body supports the lower side of the central portion of the dispersion member. The ground excavation mixing device according to claim 1, wherein the ground excavation mixing device is provided.   The ground excavation mixing apparatus according to claim 1, wherein the dispersion member is provided substantially parallel to the excavation blade.

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