JPH1082034A - Rubber weir group - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rubber weir group, by which fishes can ascend a river easily even when the water level of the river lowers and which is not damaged when fishes flow down. SOLUTION: Since recessed sections 12A, 14A, 16A are formed on the overflow surfaces of rubber weirs 12, 14, 16 constituting the rubber weir group 10 and the overflow surfaces are lowered partially, fish passes, on which fishes ascend, can be ensured even when a water level on the upstream side lowers. Since the places of the recessed sections 12A, 14A, 16A are displaced in the river-width direction and formed zigzag, the flow of water is slowed, and fishes can ascend easily. Retarding basins, in which fishes cam rest, are constituted by arranging a plurality of the rubber weirs 12, 14, 16 at regular intervals in the flow-down direction of the river, heads among the rubber weirs and the rubber weirs are reduced, and fishes are not damaged when fishes flow down.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to the construction of a river,
The present invention relates to a group of rubber weirs having a fishway as a passage for migrating fish.

[0002]

2. Description of the Related Art Rubber dams have been put into practical use as dams for blocking the flow of a river and adjusting the flow rate. As shown in FIG. 6, the rubber weir 40 is formed by folding the rubber film 42 in two, and fixing the overlapped portion to the riverbed 46 with bolts 48. Thus, it functions as a weir.

[0003] Such a rubber weir 40 has a uniform height along the width direction of the river, so that when the water level on the upstream side falls, the water does not overflow, so that fish cannot go up. To cope with this, the fluid is discharged from the hollow portion 44 and the rubber weir 4
Although a method of reducing the height of 0 is conceivable, the river management becomes complicated.

[0004] When fish flow from upstream to downstream,
If the head from the top surface (overflow surface) of the rubber weir 40 to the riverbed on the downstream side is large, it will be damaged.

[0005]

SUMMARY OF THE INVENTION In view of the above facts, the present invention provides a group of rubber weirs that allows fish to run up even when the water level of a river drops and that does not suffer damage when the fish flow down. As an issue.

[0006]

According to the first aspect of the present invention, the rubber weir is arranged so as to block the river, and expands or contracts to adjust the water level of the river.

A concave portion is formed on the overflow surface of the rubber weir, and even if the water level on the upstream side falls, water flows from the concave portion, so that a fishway for fish to run up can be secured. Also,
By arranging a plurality of rubber weirs at predetermined intervals in the flowing direction of the river, a basin in which fish can rest can be formed between the rubber weirs.

According to the second aspect of the invention, the positions of the concave portions of the adjacent rubber dams are shifted in the river width direction. For this reason, the water flowing from the concave portion meanders, the flow becomes gentle, and the fish can go up without difficulty.

According to the third aspect of the present invention, the height of the overflow surface of the rubber weir is gradually reduced toward the downstream.
As a result, the head between the rubber weir and the rubber weir is reduced, and the fish is not damaged when going downstream.

According to the fourth aspect of the present invention, the riverbed surface on which the rubber weir is installed is partially cut down, and the lower surface of the rubber weir is expanded so that the lower surface of the rubber weir fits into the cut-down portion. A recess is formed in a portion of the overflow surface corresponding to the portion. Therefore, a commonly used rubber weir can be used as it is.

According to the fifth aspect of the present invention, the rubber sheet constituting the rubber weir is partially recessed to form a recess. For this reason, the work process of cutting down the riverbed becomes unnecessary.

[0012]

1 to 3 show a rubber weir group 10 according to the present embodiment. The rubber weir group 10 includes rubber weirs 12, 14 whose height has been reduced from upstream to downstream.
16.

The rubber weirs 12, 14, and 16 are formed by folding a belt-shaped rubber film 18 into two parts to form a bag.
It is constituted by being fixed to the upstream side of the riverbed 22 with bolts 20. Both ends (shore side) of the rubber film 18 are fixed to the slope L in a watertight state, so that upstream water does not leak downstream.

On the other hand, on the overflow surface on the left bank side of the rubber weir 12,
The recess 12A is formed, and the height of the rubber weir 12 is partially reduced. On the overflow surface of the rubber weir 14,
A recess 14A is formed on the right bank side so as to be shifted from the recess 12A in the river width direction. Further, a recess 16A is formed on the left bank side of the overflow surface of the rubber weir 16 so as to be shifted from the recess 14A in the river width direction.

Thus, the recesses 12A, 14A, 16A
As shown in FIG. 3, the water overflows from the recesses 12A, 14A, and 16A even when the water level on the upstream side drops, so that the fish The upper fishway can be secured. Also, the recesses 12A, 14A,
Since the position of 16A is staggered in the river width direction, the flow is meandering, the flow of water flowing from the concave portion is gentle, and the fish can go up without difficulty.

As a method for forming a concave portion on the overflow surface of the rubber weir, as shown in FIG. 4, rubber weirs 12, 14, 16 are used.
Is cut down to provide the grooves 26, 28, 30 and expanded so that the lower surfaces of the rubber weirs 12, 14, 16 are fitted. , 14A, 16A. This allows a commonly used rubber weir to be used as is.

Further, as shown in FIG.
The rubber films 32 constituting the parts 4 and 16 may be partially recessed to form recesses. This eliminates the need for a work process such as cutting down the riverbed 22.

Which of the above two methods is to be adopted depends on the condition of the river where the rubber weir group 10 is installed.

Next, the operation of the rubber weir group according to this embodiment will be described. Rubber weirs 12, 14, 16 constituting the rubber weir group 10
Adjusts the water level of the river by expanding or contracting. The overflow surfaces of the rubber weirs 12, 14, 16 have concave portions 12A, 14A,
A and 16A are formed, and the overflow surface is partially lowered, so that even if the water level on the upstream side drops, a fishway for fish to run up can be secured. In addition, since the positions of the recesses 12A, 14A, and 16A are shifted in the river width direction and are staggered, the flow of water becomes gentle, and fish can go up without difficulty.

Also, by arranging a plurality of rubber weirs 12, 14, 16 at predetermined intervals in the downflow direction of the river,
A retarding pond where fish can rest is formed, and the head between the rubber weirs is reduced, so that the fish is not damaged when going downstream.

[0021]

According to the present invention, the fish can easily run up even if the water level of the river drops, and the fish does not suffer damage when flowing down.

[Brief description of the drawings]

FIG. 1 is a partial perspective view showing a rubber weir group according to the present embodiment.

FIG. 2 is a cross-sectional view illustrating a rubber weir group according to the present embodiment.

FIG. 3 is a cross-sectional view showing a rubber weir group according to the present embodiment.

FIG. 4 is a front view showing a method of forming a concave portion of the rubber weir constituting the rubber weir group according to the present embodiment.

FIG. 5 is a front view showing a method of forming a concave portion of the rubber weir constituting the rubber weir group according to the present embodiment.

FIG. 6 is a sectional view showing a conventional rubber weir.

[Explanation of symbols]

 12 rubber weir 14 rubber weir 16 rubber weir 12A concave 14A concave 16A concave

Claims (5)

[Claims] 1. A rubber weir, which is arranged so as to block a river and expands or contracts to adjust the water level of the river, wherein a rubber weir having a recess for a fishway formed on an overflow surface is provided in a downstream direction of the river. A group of rubber weirs, characterized by being arranged at a plurality of intervals. 2. The position of the concave portion of the adjacent rubber weir,
The group of rubber weirs according to claim 1, wherein the groups are shifted in a river width direction. 3. The group of rubber weirs according to claim 1, wherein a height of an overflow surface of the rubber weir is gradually reduced toward downstream. 4. The concave portion is formed by partially cutting down a riverbed surface on which the rubber weir is installed, and fitting a lower surface of the rubber weir into the cut-down portion. The rubber weir according to claim 3. 5. The rubber weir according to claim 1, wherein the concave portion is formed by partially recessing a rubber sheet constituting the rubber weir.