JP3638683B2 - Fishway - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fishway provided in a river.
[0002]
[Prior art]
In the dike with a large head constructed in the river, a channel that separates the fishway and waterway is provided so as not to prevent the fish from going up.
Such a fishway needs to have a flow rate that allows the fish that goes up and down to swim, and therefore has the following structure.
[0003]
FIG. 7 is an explanatory diagram of the first prior art, and has a structure in which fishes can go up by providing partition walls 1 in a staircase pattern in a direction orthogonal to the flow from the upstream side to the downstream side and forming the pools 2 respectively.
FIG. 9 is an explanatory diagram of the second prior art, in which a rough material 3 made of natural stone or concrete is provided on the aqueduct floor from the upstream side to the downstream side to give resistance to the flow so that the fish can go up.
[0004]
[Problems to be solved by the invention]
According to the conventional techniques such as these, the flowing water and the falling sediment gravel concentrate on the fishway, and as a result, in the first prior art, the sediment 4 is deposited and buried in the pool over time as shown in FIG. There is a problem that the desired function cannot be achieved.
[0005]
Further, in the second prior art, as shown in FIG. 10, there is a problem that the rough material is worn or missing, and the expected function cannot be obtained even in this technique.
[0006]
[Means for Solving the Problems]
Therefore, the present invention is characterized in that, in a flow path type fishway provided on a levee body with a head constructed in a river, a columnar material made of elastic material is arranged at a desired interval in a certain section of the roadbed. To do.
By comprising in this way, the speed of the flowing water of the lower layer area which passes a fishway can be made small, and it can be set as the flowing water speed convenient for fish going up.
[0007]
In addition, the columnar material elastically deforms against the flow of sediment and gravel, so that it absorbs collision energy, so it has excellent impact resistance and wear resistance. It is possible to secure a fishway over a long period of time because it is not allowed to pass and accumulate on the river bed.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
1 is a front view, FIG. 2 is a side view, and FIG. 3 is a partially enlarged view. In the figure, reference numeral 5 denotes a columnar material, which is made of a material having elasticity excellent in wear resistance such as rubber and synthetic resin. In addition, it is arranged in a desired pattern such as a staggered pattern or a lattice pattern on the riverbed of the flow path type fishway, and is erected at a desired interval.
[0009]
The elastic material of the columnar member 5 can be obtained by finishing the degree of bending by finishing the hardness of a material such as rubber or synthetic resin to a desired hardness. Further, as shown in FIG. Alternatively, a partially laminated structure of synthetic fiber or steel and rubber or synthetic resin, or rubber or synthetic resin having different hardness may be used.
The diameter, height, deformation degree, arrangement density, and the like of the columnar member 5 are determined by conditions such as the water flow conditions of the fishway and the amount and size of the falling soil gravel. Furthermore, the cross-sectional shape of the columnar member 5 is preferably circular, but this is not always necessary, and an oval shape such as an ellipse or a polygonal shape may be used depending on conditions.
[0010]
In addition, the columnar member 5 may be installed on the riverbed 6 as shown in FIG. 3. The lower part of the columnar member 5 may be embedded in the riverbed 6, but the anchor plate or the like provided on the riverbed 6 may be installed on the riverbed. It is good also as a structure attached by processing.
Furthermore, as shown in FIG. 5, it is good also as a structure which manufactured in the state which connected the some columnar material 5 in the bottom part, and embed | buried the columnar material 5 in the riverbed 6. As shown in FIG.
[0011]
According to the configuration as described above, the velocity of the flowing water in the lower layer region passing through the fishway is replaced by the shielding action and elastic deformation energy of the columnar members 5 arranged at predetermined intervals. A convenient flow rate can be achieved. As a result, it is possible to move up between the columnar members 5.
In addition, the columnar material 5 is excellent in impact resistance and wear resistance because the columnar material 5 absorbs collision energy by elastic deformation as shown in FIG. Since it bends and the distance between each other increases, it is possible to secure a fishway over a long period of time without causing sediments to flow and deposit.
[0012]
The arrangement of the columnar material 5 on the riverbed 6 does not have to be the full width of the riverbed 6. As shown in FIG. 6, the columnar material 5 has a columnar shape in a part of the flow direction of the riverbed 6 (the center in the present embodiment). By forming the area 7 where the material 5 is not disposed, the falling soil gravel can be intensively flowed from the area 7. As a result, the intrusion of earth and sand between the columnar members 5 can be reduced, and it is possible to prevent sedimentation of the sand and gravel between the columnar members 5 as well as to prevent the fish from going upstream.
[0013]
【The invention's effect】
According to the present invention described in detail above, by arranging the elastic columnar members at the desired intervals on the riverbed of the fishway, it is possible to reduce the speed of flowing water in the lower region passing through the fishway, It has the effect of being able to make the water flow speed convenient for the.
Moreover, since the columnar material elastically deforms against the flow of earth and sand gravel, it absorbs collision energy and thus has an effect of being excellent in impact resistance and wear resistance.
[0014]
In addition, since the columnar material is bent, the distance between each other is increased, and sediment and gravel are allowed to flow and do not accumulate on the riverbed, so that the fishway can be secured over a long period of time.
[Brief description of the drawings]
FIG. 1 is a front view showing an embodiment. FIG. 2 is a side view. FIG. 3 is a partially enlarged view. FIG. 4 is an explanatory view showing an example of a cross-sectional structure. 6 is a front view showing another embodiment. FIG. 7 is an explanatory diagram of the first conventional example. FIG. 8 is an explanatory diagram of the first conventional example. FIG. 9 is an explanatory diagram of the second conventional example. Explanatory drawing of the second conventional example [Explanation of symbols]
5 Columnar 6 Riverbed 7 Area not arranged

Claims (2)

In a flow path type fishway built on a bank with a head constructed in a river,
Fish ladder, characterized in that arranged in the desired spacing columnar member having an elastic member made of flexible to a certain section of the subgrade. In a flow path type fishway built on a bank with a head constructed in a river,
Fish ladder, characterized in that arranged in the desired spacing columnar material constant region of road bed with elastic material made of flexible constant interval so as not to place.

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