JP2006265951A - Under-reamed supporting plate attached rotating buried pile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an under-reamed supporting plate attached rotating buried pile capable of being quickly penetrated in the ground and, at the same time, improving bearing capacity. <P>SOLUTION: The under-reamed supporting plate attached rotation buried pile is so constituted that a plurality of approximately fan-shaped under-reamed supporting plates 3 formed by a projectingly curved surface of the base in the outer circumference of the lower end of a steel pipe 2 are slopingly projected to the direction of a shaft of the steel pipe 2 at an interval so as to place the projection curved surface in the lower side, at the same time, excavation edges 5 are formed in the lower side edge sections of the under-reamed supporting plates 3, at the same time, a space between the under-reamed supporting plates 3 and 3 adjacent to each other is used as a soil moving passage 7 moving soil 6 to the above and that the soil 6 is excavated with the excavation edges 5 formed in the lower side edge sections of the under-reamed supporting plates 3 to bury it in the ground 8 with a predetermined depth while moving it to the above from the soil moving passage 7 by rotating the under-reamed supporting plates 3 mounted to the steel pipe 2 to support it by the under-reamed supporting plates 3 arranged in the shape of a parabola. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to an improvement of a rotary buried pile with an expanded bottom support plate with improved support force.

In general, when building a wooden house or a low-rise steel structure in a landfill or a land with weak embankment, a pile landing work is performed in which piles are driven into the ground in advance at predetermined intervals along the shape of the concrete foundation. The concrete foundation is constructed from.

Various methods have been conventionally used for this pile land industry. For example, the pile driving method is a method in which concrete piles and steel pipe piles are driven into the ground with a hammer. Construction is not possible where there is a building.

For this reason, there is a screw pile (for example, Patent Document 1) in which a screw blade is attached to the tip of a steel pipe and embedded while rotating as a pile without generating noise, but the area of the screw blade cannot be taken large and is soft. When buried in the ground, there was a problem that a large bearing capacity could not be obtained. A bottomed steel pipe is also proposed in which a frustoconical bottomed support plate with a large upper edge diameter and a small lower edge diameter is attached to the outer periphery of the lower end of the steel pipe, and a triangular excavating blade is attached to the tip (patent) Reference 2).

However, the bottomed steel pipe to which this truncated cone-shaped expanded support plate is attached has the disadvantage that the excavated soil cannot be quickly discharged upward and cannot be buried deeply in the ground because the lower opening of the truncated cone shape is narrow. there were.
JP 2004-332234 A FIG. 8 of Japanese Patent No. 3575005

The present invention improves the above problems and provides a rotary buried pile with an expanded bottom support plate that can be buried quickly in the ground and has an improved support force.

The rotary buried pile with a bottom-up support plate according to claim 1 of the present invention has a plurality of bottom-up support plates having a substantially fan shape with a bottom surface formed in a convex curved surface on the outer periphery of the lower end of the steel pipe. So that the steel pipe is inclined with respect to the axial direction of the steel pipe so as to be located at a lower edge of the inclined bottom expansion support plate, and the earth between the adjacent bottom expansion support plates As a soil discharge passage that discharges upward, the bottom expansion support plate attached to the steel pipe is rotated, so that the soil is excavated by the excavation blade formed at the lower edge of the bottom expansion support plate and discharged upward from the soil discharge passage. However, it is embedded in the ground at a predetermined depth and is supported by a widened support plate arranged in a parabolic shape.

The rotary buried pile with a bottom-up support plate according to claim 2 of the present invention is characterized in that two, three, or four bottom-up support plates are attached to the outer periphery of the lower end of the steel pipe.

The rotary buried pile with a bottom-up support plate according to claim 3 of the present invention is characterized in that a reinforcing rib is provided on the top surface of the bottom-up support plate. The rotary buried pile with an expanded bottom support plate according to claim 4 of the present invention is further characterized in that the lower end of the steel pipe is further closed, and a block-shaped excavating blade is protruded therefrom.

According to the rotary buried pile with a bottom-up support plate according to claim 1 of the present invention, a plurality of bottom-up support plates having a substantially fan shape having a bottom surface formed in a convex curved surface on the outer periphery of the lower end of the steel pipe. Is located on the lower side so as to be inclined with respect to the axial direction of the steel pipe, and a drilling blade is formed on the lower edge of the bottom-up support plate, and between the adjacent bottom-up support plates, Since the earth removal passage is formed, the penetration speed can be increased by efficiently excavating the earth without being misaligned by the rotation of the excavating blade and discharging the soil upward from the earth removal passage. Furthermore, since the plurality of bottom-up support plates are arranged in a parabolic shape having a convex curved surface on the lower side as a whole, the supporting force can be improved.

According to the rotary buried pile with a bottom-up support plate according to claim 2, since the two or three or four bottom-up support plates are attached to the outer periphery of the lower end of the steel pipe, a convex curved surface is formed on the lower side as a whole. While being arranged in a parabolic shape, it is possible to efficiently excavate soil by preventing misalignment.

According to the rotary buried pile with a bottom-up support plate according to claim 3, since the reinforcing rib is provided on the top surface of the bottom-up support plate, the strength of the bottom-up support plate can be improved.

Further, according to the rotary buried pile with a bottom-up support plate according to claim 4, further closing the lower end of the steel pipe, projecting a block-shaped excavation blade here, the excavation blade rotates to loosen the soil, Since it is scraped off by the excavating blade of the expanded bottom support plate and sent upward, it can penetrate quickly.

Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS. In the figure, reference numeral 1 denotes a rotary buried pile with a bottom-up support plate, which is obtained by attaching four bottom-up support plates 3 to the outer periphery of the lower end of the steel pipe 2. The bottom-up support plate 3 has a substantially fan shape in which the bottom surface has a convex curved surface and the top surface has a concave curved surface, and a space is provided on the outer periphery of the steel pipe 2 so that the convex curved surface is positioned on the lower side. The steel pipe 2 is inclined and protruded with respect to the axial direction, and is formed in a parabolic shape as a whole.

Further, an excavation blade 5 is formed on the inclined lower edge of the bottom expansion support plate 3 having a substantially sector shape, and the center side of each bottom expansion support plate 3 is integrally connected at the lower end of the steel pipe 2 as shown in FIG. ing. Further, as shown in FIG. 3, a soil discharge passage 7 for discharging the soil 6 upward is formed obliquely between the adjacent expanded bottom support plates 3, 3 of the expanded bottom support plates 3 that are inclined and projected. Yes.

When embedding the rotary buried pile 1 with the expanded bottom support plate having the above-described configuration, for example, a hydraulic motor having a weight is attached to the arm of the backhoe, the expanded bottom support plate 3 of the rotary embedded pile 1 is placed downward, and the upper end is pressed. Support vertically. Next, a load is applied with a weight, and the rotary buried pile 1 is embedded in the ground 8 while being rotated by a hydraulic motor. As shown in FIG. 3, four bottom support plates 3 are projected at equal intervals at the lower end of the rotary buried pile 1 and the excavation blade 5 is formed at the lower edge thereof. The soil 6 is scraped and excavated, and the soil 6 is discharged obliquely upward through the soil discharge passage 7.

Since the rotary buried pile 1 buried to a predetermined depth in this way is formed in a parabolic shape in which the four expanded bottom support plates 3 form a convex curved surface on the lower side as shown in FIG. Supporting force is large and can prevent settlement. As a result of examining the difference in support force depending on the shape of the expanded bottom support plate 3, when the bottom surface of the expanded bottom support plate is horizontal, or protrudes in a V shape on the lower side, or when the lower side is a parabolic shape having a concave curved surface As compared with the above, it has been found that the supporting force is most improved in the case of a parabolic shape in which a convex curved surface is formed on the lower side.

Therefore, since the four expanded bottom support plates 3 are arranged so as to form a parabolic shape having a convex curved surface on the lower side as a whole, the support force is improved and the soil 6 is efficiently excavated by the four excavating blades 5. Thus, the soil can be quickly penetrated without being misaligned by discharging the soil upward from the soil discharge passage 7.

FIGS. 4 and 5 show another embodiment of the present invention in which the rotary buried pile 1 is substantially formed on the outer periphery of the lower end of the steel pipe 2 with a bottom surface having a convex curved surface and a top surface having a concave curved surface. The three expanded bottom support plates 3 having a fan shape are provided with an interval on the outer periphery of the steel pipe 2 so that the convex curved surface is positioned on the lower side, and are inclined and protruded with respect to the axial direction of the steel pipe 2. The whole is formed in a parabolic shape. Further, an excavating blade 5 is formed on the inclined lower edge of the bottom-up support plate 3 having a substantially sector shape, and the center side of each bottom-up support plate 3 is integrally connected at the lower end of the steel pipe 2 as shown in FIG. ing. This rotary buried pile 1 can also penetrate quickly and improve the supporting force.

FIG. 6 shows another embodiment in which the present invention is different. The rotary buried pile 1 has three bottom-up support plates 3 having a substantially fan shape on the outer periphery of the lower end of the steel pipe 2, and the convex curved surface below. The outer periphery of the steel pipe 2 is provided with an interval so as to be positioned on the side, and is inclined and protruded with respect to the axial direction of the steel pipe 2, and is formed in a parabolic shape as a whole. Further, a closing plate 9 is attached to the lower end of the steel pipe 2, and three semicircular block-shaped excavating blades 10 are projected.

In this rotary buried pile 1, the semicircular block-shaped excavating blade 10 projecting from the lower end of the steel pipe 2 rotates to loosen the soil 6, and further scraped with the excavating blade of the expanded bottom support plate 3 and sent upward. Can penetrate. The block-shaped excavation blade 10 may have another shape such as a triangle or a pentagon.

FIG. 7 shows another embodiment in which the present invention is different. The rotary buried pile 1 has two bottom-up support plates 3 having a substantially fan shape on the outer periphery of the lower end of the steel pipe 2, and the convex curved surface below. The outer periphery of the steel pipe 2 is provided with an interval so as to be positioned on the side, and is inclined and protruded with respect to the axial direction of the steel pipe 2, and is formed in a parabolic shape as a whole.

FIG. 8 shows another embodiment of the present invention in which a plurality of arc-shaped ribs 11 are formed on the upper surface of a fan-shaped bottom-up support plate 3 to improve the strength of the bottom-up support plate 3. be able to. Further, the rib 11 may be formed on the bottom surface of the expanded bottom support plate 3.

The rotary buried pile 1 may have a structure in which a bottom-up support plate 3 formed by press-molding a steel plate is welded to the outer periphery of the lower end of the steel pipe 2 and the bottom end portion of the steel pipe 2 and a plurality of bottom-up support plates 3 are integrated. It may be cast and molded and welded to the lower end of the steel pipe 2. Further, if the number of the bottom expansion support plates 3 is 5 or more, the soil removal passage 7 between the adjacent bottom expansion support plates 3 and 3 is narrowed and the discharge efficiency is lowered.

The rotary buried pile with an expanded bottom support plate of the present invention can be widely used not only as a foundation pile of a house or a building but also as a road sign, a pillar of an advertising tower, a foundation pile of a concrete retaining wall, or the like.

It is a perspective view of the rotation embedding pile which attached 4 sheets of bottom expansion support plates by one embodiment of the present invention. It is a bottom view which shows the rotation buried pile of FIG. It is explanatory drawing which shows the state which has penetrated the underground rotation pile with a bottom-up support board of FIG. 1 in the ground. It is a perspective view of the rotation embedding pile which attached three bottom expanded support plates by other embodiment of this invention. It is a bottom view which shows the rotation buried pile of FIG. It is the perspective view which looked at the rotation buried pile which projected the semicircular block-shaped excavation blade at the lower end of the steel pipe by other embodiment from which this invention differs from diagonally downward. It is a perspective view of the rotation embedding pile which attached the two bottom expanded support plates by other embodiment of this invention. It is a perspective view of the bottom-up support plate which formed the rib by other embodiment of this invention.

Explanation of symbols

1 Rotating buried pile with expanded support plate
2 Steel pipe
3 Expanded bottom support plate
5 Drilling blade
6 Sat
7 earth removal passage
8 underground
9 Blocking plate
10 Semi-circular block-shaped drilling blade
11 Ribs

Claims (4)

A plurality of bottom expansion support plates having a substantially fan shape whose bottom surface is formed with a convex curved surface on the outer periphery of the lower end of the steel pipe, with an interval so that the convex curved surface is located on the lower side, with respect to the axial direction of the steel pipe A bottom-up support plate attached to a steel pipe as a soil discharge passage that is inclined and protrudes, forms a digging blade at the lower edge of the sloped bottom-up support plate, and discharges soil between the adjacent bottom-up support plates , The soil is excavated with the excavating blade formed on the lower edge of the bottom-up support plate, and is buried in the ground at a predetermined depth while being discharged upward from the excavation passage. A rotary buried pile with a bottom-up support plate, characterized in that it is supported by a placed bottom-up support plate. 2. The rotary buried pile with a bottom-up support plate according to claim 1, wherein two, three, or four bottom-up support plates are attached to the outer periphery of the lower end of the steel pipe. The rotary buried pile with a bottom-up support plate according to claim 1, wherein reinforcing ribs are provided on the top surface of the base-up support plate. The rotary buried pile with a bottom-up support plate according to claim 1, wherein the lower end of the steel pipe is further closed, and a block-shaped excavating blade is protruded therefrom.