JP3998087B2 - Driftwood prevention fence - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a driftwood prevention fence installed on a river bed or the like in order to stop the drifting of driftwood.
[0002]
[Prior art]
The driftwood prevention fence is installed on the riverbed of the valley to prevent the driftwood from flowing further downstream and causing damage. The driftwood is kept without interfering with the flow of water.
Conventionally, as a steel driftwood prevention fence, for example, as shown in FIG. 10, a lower part of a separation type fence body 1 in which a steel pipe is assembled into, for example, an A shape is crossed across a flow as shown in FIG. Separation type structure embedded directly into the concrete foundation 2 to be placed at intervals, or a structure in which the separation type fence bodies assembled in various shapes, such as A type, are connected by a cross beam, although not shown in the figure. An integrated structure in which the lower part of a grid-like fence body in which steel pipes are assembled in a grid form so as to constitute the entire fence is directly embedded in a concrete foundation is adopted. Although there are various other structures for the fence body, the conventional driftwood prevention fences are structures in which the lower part of the fence body is directly embedded in the concrete foundation.
[0003]
[Problems to be solved by the invention]
Only driftwood does not necessarily flow into the driftwood prevention fence, but debris flow or the like may come in, and the fence body may be damaged at that time. When it breaks, it is necessary to replace a part or all of the fence body. However, it is not easy and expensive to replace the fence body in which the lower part is directly embedded in the concrete foundation.
The present invention has been made in view of the above circumstances, and an object thereof is to provide a driftwood prevention fence that can be easily and inexpensively replaced even if it is damaged by a debris flow or the like.
[0004]
[Means for Solving the Problems]
The invention of the driftwood prevention fence of the present invention that solves the above problems is composed of a plurality of pillar-like fence bodies installed at intervals in the width direction on a river bed or the like, and each pillar-like fence body has a foundation with an upper edge at the foundation. The pile body is configured by inserting a steel pipe for a pile body into a buried steel pipe for a foundation embedded in a manner protruding from the surface, and filling a gap between the embedded steel pipe for the foundation and the steel pipe for a pile body, A plurality of ribs extending radially about the entire depth of the embedded steel pipe for the foundation are provided radially on either the outer periphery of the portion inserted into the embedded steel pipe for the foundation or the inner periphery of the embedded steel pipe for the foundation. A flange is integrally provided at an upper end edge of the embedded steel pipe, and a stopper fixed to the flange with a bolt is provided on an outer periphery of a lower portion of the pile body steel pipe .
[0008]
According to a second aspect of the present invention, in the driftwood prevention fence according to the first aspect, an upper surface portion of earth and sand filled in a gap between the embedded steel pipe for foundation and the steel pipe for pile body is covered with asphalt. And
[0009]
Claim 3 is the driftwood prevention fence according to claim 1 or 2, wherein the lid is fixed to the inner surface slightly below the upper end surface of the steel pipe for pile body, and the upper surface of the lid is for lifting with a hook hole extending over the steel pipe diameter. The plate material is fixed.
[0010]
According to a fourth aspect of the present invention, in the driftwood prevention fence according to any one of the first to third aspects , at least a plurality of reinforcing ribs are fixed to the back surface of the flange of the embedded steel pipe for the foundation at intervals in the circumferential direction, and at least Two reinforcing ribs are provided with hook holes.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to FIGS. FIG. 1 is a front view of a driftwood prevention fence 10 according to an embodiment of the present invention. 2 is an enlarged front view of one columnar fence body 11 in FIG. 1, FIG. 3 is a left side view of FIG. 2, FIG. 4 is a plan view of FIG. 2, and FIG. FIG. 6 is a cross-sectional view taken along the line BB in FIG. 2, and FIG. 7 is an exploded view of the columnar fence 11.
As shown in these figures, this driftwood prevention fence 10 is composed of a plurality of support-like fence bodies 11 installed at intervals in the width direction of the river bed, and each support-like fence body 11 hits the river bed. An embedded steel pipe 13 for the foundation is embedded in the concrete foundation 12 and the steel pipe 14 for the pile body is inserted into the embedded steel pipe 13 for the foundation, and the gap between the embedded steel pipe 13 for the foundation and the steel pipe 14 for the pile body is filled with sand. Configured.
[0012]
As shown in FIGS. 4, 5, 7, etc., the pile steel pipe 14 is a round steel pipe, and eight vertically long ribs 16 are fixed by welding in a radial arrangement on the outer periphery of the lower part thereof. A stopper 17 is welded and fixed in contact with the upper end of the rib 16 at that location. The stopper 17 has a triangular reinforcing plate 17b welded and fixed to the upper surface of a horizontal plate 17a having two bolt insertion holes. Also, as shown in FIGS. 4 and 7, a disk-shaped lid 18 is welded and fixed to the inner surface slightly below the upper end surface of the pile steel pipe 14, and the hook hole 19 a spans the diameter of the steel pipe on the upper surface of the lid 18. The attached lifting plate 19 is fixed by welding. A reinforcing plate 20 is fixed by welding at a right angle to the lifting plate 19.
[0013]
The foundation embedded steel pipe 13 is a round steel pipe having an inner diameter in which the lower part of the pile body steel pipe 14 can be fitted together with the outer peripheral rib 16, and a bolt insertion hole 21 a (see FIG. 7) is opened at one position on the upper end edge. The flange 21 is fixed by welding, and rectangular reinforcing ribs 22 with hook holes 22a are welded and fixed at four orthogonal positions on the lower surface of the flange 21, and triangular reinforcing ribs 23 are fixed by welding. ing.
[0014]
When constructing the above driftwood prevention fence 10, first, the embedded steel pipe 13 for foundation is embedded in the concrete foundation 12 with a gap. In this case, the foundation embedded steel pipe 13 can be supported and transported by suspending it with a crane using the hook holes 22a formed in the reinforcing ribs 22 of the foundation embedded steel pipe 13.
After the concrete is hardened, a crane hook is hung on the hook hole 19 a at the upper end of the pile steel pipe 14, and the pile steel pipe 14 is lifted and inserted into the foundation embedded steel pipe 13. Next, the bolt insertion hole of the stopper 17 of the pile body steel pipe 14 is aligned with the bolt insertion hole 21a of the flange 21 of the foundation embedded steel pipe 13 and is fastened and fixed with the bolt 25 to ensure the pile body steel pipe 14 is prevented from coming off. To. In addition, it is preferable in terms of strength that the embedded steel pipe 13 for the foundation and the steel pipe 14 for the pile body are arranged so that the stopper 17 is on the downstream side.
Next, sand 26 is filled in the gap between the embedded steel pipe 13 for the foundation and the steel pipe 14 for the pile body. The top surface of the filled sand 26 is further covered with asphalt 27. This can prevent the sand 26 from being sucked into the flow. With this asphalt coating, the installation for one columnar fence body 11 is completed. When the pile steel pipe 14 is inserted in the same manner for the other embedded steel pipes 13 for foundations, the construction of the driftwood prevention fence 10 is completed.
[0015]
In the driftwood prevention fence 10 in which the columnar fence bodies 11 are arranged at intervals as described above, the distance is set to a distance appropriately determined by various experiments or the like, so that the flowing driftwood is almost surely obtained. It is possible to capture and prevent the driftwood from flowing downstream and causing damage.
[0016]
If the pile steel pipe 14 of the pillar-shaped fence body 11 is damaged due to a debris flow approaching the driftwood prevention fence 10, the bolt 25 is removed and the stopper 17 is removed from the flange 21, and the pile steel pipe is used using a crane. 14 is pulled out from the embedded steel pipe 13 for the foundation, and a new pile steel pipe 14 is inserted into the embedded steel pipe 13 for the foundation. At that time, the sand 25 remaining in the foundation embedded steel pipe 13 can be easily sucked out by a vacuum (vacuum suction device) or the like. Since the foundation embedded steel pipe 13 embedded in the concrete foundation 12 is hardly damaged, it is only necessary to replace the replaceable pile steel pipe 14 and the replacement work is simple and the cost is reduced.
[0017]
It should be noted that such a detachable pile-shaped columnar fence body is considered to be weaker than the conventional A-shaped fence body 1 or grid-like fence body, but the pile steel pipe 14 Since there is little debris flow enough to damage the bridge, the idea is to replace it at that time, there is no hindrance to the work as a driftwood prevention fence, and the construction cost of the driftwood prevention fence, As a whole, the maintenance cost including repair in the event of damage can be reduced.
[0018]
In the above driftwood prevention fence 10, since the sand 25 is filled in the gap between the foundation embedded steel pipe 13 and the pile steel pipe 14, the flow force acting on the pile steel pipe 14 causes the sand 25 to flow. To the foundation embedded steel pipe 13. At that time, since the sand 25 has a buffering effect and a load distribution effect, the stress transmission to the embedded steel pipe 13 for the foundation becomes uniform, and a large force acts locally on the steel pipe 14 for piles to cause deformation or breakage. Can be prevented. At that time, the rib 16 functions as a spacing member that holds a gap between the embedded steel pipe 13 for the foundation and the steel pipe 14 for the pile body, and effectively produces a sand cushioning effect and a load distribution effect.
[0019]
In the above-described embodiment, the columnar fence body 11 is provided vertically, but may be installed such that the upper end side is inclined in the upstream direction with respect to the flow direction of the river. In this way, when driftwood flows, it will be fastened to the driftwood prevention fence so as to ride on the driftwood previously fastened to the driftwood prevention fence, so that the later driftwood moves down the previous driftwood (water bottom) It is possible to prevent driftwood from climbing over the driftwood prevention fence.
[0020]
In the above embodiment, round steel pipes are used as the embedded steel pipes for piles and the steel pipes for pile bodies, but the embedded steel pipes 13 ′ for foundations and the piles are used like the pillar-shaped fence bodies 11 ′ shown in cross section in FIG. A square steel pipe may be used as the body steel pipe 14 '.
Further, in the embodiment, the rib 16 is provided on the outer periphery of the pile steel pipe 14, but it is also possible to provide this rib as a spacing member radially inwardly on the inner periphery of the foundation embedded steel pipe 13.
[0021]
In addition, as earth and sand with which the clearance gap between the embedding steel pipe for foundations and the steel pipe for pile bodies is filled, it is desirable that there is no adhesiveness between soil particles, and although sand is usually used, it is not necessarily limited to sand.
[0022]
【The invention's effect】
According to the driftwood prevention fence of the present invention, it is composed of a plurality of pillar-shaped fence bodies installed at intervals, and each pillar-like fence body can attach and detach a steel pipe for a pile body to an embedded steel pipe for a foundation embedded in a foundation. Since it is an inserted configuration, if it is damaged by debris flow after installation, it can be repaired simply by replacing the steel pipe for pile body, and the repair work is very simple and the repair cost is low.
In addition, because the gap between the embedded steel pipe for the foundation and the steel pipe for the pile body is filled with earth and sand, the stress transmission to the embedded steel pipe for the foundation becomes uniform due to the buffer effect and load distribution effect of the earth and sand, and the pile body It is possible to prevent the steel pipe from being deformed or broken due to a large force acting locally on the steel pipe.
[0023]
In addition, a plurality of ribs extending radially about the entire depth of the embedded steel pipe for foundation are provided radially on either the outer periphery of the portion inserted into the embedded steel pipe for foundation or the inner periphery of the embedded steel pipe for foundation. since it is, the rib acts as a distance holding member for holding a gap between the steel pipe embedding foundation and pile body for steel, to enable buffering effect and load distribution effect by the sand.
In addition, the stopper can reliably prevent the pile steel pipe from coming off.
[0024]
According to the second aspect of the present invention, sand can be prevented from being sucked out by the asphalt on the upper surface of the sand, and the sand cushioning effect and the load distribution effect can be maintained.
According to 請 Motomeko 3, support and transport the like pile body for steel pipes is facilitated.
According to the fourth aspect , it becomes easy to support and carry the embedded steel pipe for the foundation.
[Brief description of the drawings]
FIG. 1 is a front view of a driftwood prevention fence according to an embodiment of the present invention.
2 is an enlarged view of one strut-shaped fence body in FIG. 1. FIG.
FIG. 3 is a left side view of FIG. 2;
4 is a plan view of FIG. 2. FIG.
5 is a cross-sectional view taken along line AA in FIG.
6 is a cross-sectional view taken along the line BB in FIG.
FIG. 7 is an exploded view of the columnar fence body.
FIG. 8 shows an embodiment using a square steel pipe as an embedded steel pipe for a foundation and a steel pipe for a pile body, and is a cross-sectional view of one columnar fence body in a driftwood prevention fence (a figure corresponding to FIG. 5). .
FIG. 9 is a front view of a conventional driftwood prevention fence.
10 is an enlarged cross-sectional view taken along the line CC in FIG. 9. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Driftwood prevention fence 11 Prop-like fence body 12 Concrete foundation 13 Embedded steel pipe for foundation 14 Square steel pipe for pile body 16 Rib 17 Stopper 18 Lid 19 Lifting plate 19a Hook hole 21 Flange 21a Bolt insertion hole 22, 23 Reinforcement rib 22a Hook hole 25 bolt 26 sand (earth and sand)
27 Asphalt

Claims (4)

It consists of a plurality of strut-shaped fence bodies installed at intervals in the width direction on the riverbed, etc., and each strut-shaped fence body is piled on an embedded steel pipe for foundations embedded in such a manner that the upper edge protrudes from the foundation surface. A steel pipe is inserted, and the gap between the embedded steel pipe for foundation and the steel pipe for pile body is filled with earth and sand,
In one of the outer periphery of the portion inserted into the foundation embedded steel pipe in the pile body steel pipe or the inner periphery of the foundation embedded steel pipe, a plurality of ribs extending substantially the entire depth of the foundation embedded steel pipe are provided radially,
A driftwood prevention fence, wherein a flange is integrally provided at an upper end edge of the embedded steel pipe for foundation, and a stopper fixed to the flange with a bolt is provided on an outer periphery of a lower part of the steel pipe for pile body.   The driftwood prevention fence according to claim 1, wherein an upper surface portion of earth and sand filled in a gap between the embedded steel pipe for foundation and the steel pipe for pile body is covered with asphalt.   The lid is fixed to the inner surface slightly lower than the upper end surface of the pile steel pipe, and a lifting plate with a hook hole extending over the diameter of the steel pipe is fixed to the upper surface of the lid. Driftwood prevention fence. 4. A plurality of reinforcing ribs are fixed to a back surface of a flange of the embedded steel pipe for foundation in a circumferential direction, and hook holes are provided in at least two reinforcing ribs . The driftwood prevention fence of any one of Claims .

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