JP3844895B2 - Block with fish nest - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fish nest block to be installed on the bottom of a river or an irrigation channel or the seabed.
[0002]
[Prior art]
A conventional cruciform block for breeding fish by installing it at the bottom of the river will be described with reference to FIGS. FIG. 7 is a plan perspective view showing a usage state of the cruciform block 1, and shows a state where a plurality of cruciform blocks 1 are connected to each other by bolts 2 and installed on the riverbed 3. FIG. 8 is a front view showing one of the plurality of cross-shaped blocks 1 installed on the riverbed 3. The cross-shaped block 1 has a cross shape in plan and has a predetermined thickness, and becomes thinner as it goes downward.
[0003]
When the cruciform block 1 is installed, as shown in FIG. 8, the lower part is buried in the layer 4 of earth and sand and pebbles accumulated on the riverbed 3 in a state where each cruciform block 1 is erected. A chestnut 5 having a diameter of about 60 to 260 mm is stacked on the layer 4 and each cross-shaped block 1 is held by the layer 6 of the chestnut 5.
By installing the cruciform block 1 on the riverbed 3 along the quay of the river, the speed of the water flowing through the gap between the chestnut stones 5 can be reduced in the vicinity where the cruciform block 1 is installed. This can make the fish habitat easy environment into the gap and if Kuriishi 5 of the near side of these cross block 1, it is possible to increase the egg production of fish.
In addition, the clearance gap between the chestnuts 5 is an area through which fish can pass, and river water flows in the direction 7 shown in FIGS. 7 and 8.
[0004]
[Problems to be solved by the invention]
However, with the conventional cruciform block 1, the water flow rate can be reduced, but the fish eggs laid near the cruciform block 1 are likely to be washed away into the water, and therefore the fish propagates efficiently. There is a problem that cannot be made.
Since the cruciform block 1 is made of concrete and is integrated, one weight is heavy (about 600 kg), and therefore there is a problem that it is difficult to transport and construct, and labor and cost increase.
[0005]
Further, in the conventional cross-shaped block 1, part of the earth and sand and pebbles carried from the river by the flow of the river water is dammed and accumulated on the side surface 8 on the upper side of the installed cross-shaped block 1. The earth and sand blocked by the side surface 8 acts as a force for pushing the cruciform block 1 downstream. On the other hand, the earth and sand 4a in the vicinity of the downstream side surface 9 of the cruciform block 1 is carried downstream by the flowing water, and a depression is formed in that portion of the riverbed 3, whereby the cruciform block 1 The crushed stone 5 in the vicinity of the side surface 9 on the downstream side collapses into the depression, and as a result, the cruciform block 1 cannot be supported from the downstream side.
When the situation as described above progresses in this way, the bolts 2 that connect the cruciform blocks 1 to each other are subjected to the weight of the respective blocks, the respective bolts 2 bend, and the cruciform blocks 1 are inclined downstream. There is a problem that it looks bad.
[0006]
An object of the present invention is to provide a block with a fish nest that can propagate fish efficiently, is easy to transport and construct, and is not easily tilted by the flow of water.
[0007]
[Means for Solving the Problems]
The present invention places the rectangular body having a cavity as Sakanasu therein so diagonals substantially coincides with the direction of the water or seawater flows, the bottom of the body, generally which extend substantially horizontally to the surroundings A square base is provided. The main body is provided with a fish inlet / outlet which communicates the cavity and the outside world on the side wall facing the downstream direction of the flow. Moreover, the said base part has the edge substantially parallel to the diagonal of the said main body in the circumference | surroundings.
[0008]
In a preferred embodiment, four protrusions extend from the corner portions of the main body in the diagonal direction toward the four sides, and the tips thereof extend directly above the peripheral edge of the base portion.
[0009]
The lowermost edge of the fish entrance / exit of the main body is preferably substantially the same height as the lower bottom surface of the cavity. In addition, at least a downstream portion of the flow of the foundation has a vertical through-hole that allows passage of earth and sand, and a similar through-hole may be provided in the upstream portion of the flow. desirable.
[0010]
It is advantageous in terms of manufacturing, transportation, and construction that the above-described block with fish nest is manufactured by being divided into two parts divided along one diagonal of the main body. It is desirable that the two divided portions can be coupled so that one convex portion engages with the other convex portion.
[0011]
The above-mentioned blocks with fish nests are arranged in such a manner that the peripheral edges of the respective base portions are in contact with each other, and the base portions are buried in the sediment of the riverbed or the seabed. In that case, it is desirable to connect the blocks to each other by an appropriate connector in order to prevent the arrangement relationship of the blocks from being broken.
[0012]
And it is desirable to provide a layer of chestnut on the earth and sand covering the base of the block up to a position below the protrusion on the upper part of the main body.
[0013]
As described above, the block with a fish nest according to the present invention is firmly installed because the foundation is buried in the bottom of the water or the bottom of the sea, and chestnuts are stacked on it, and the water flow is the main body. Since it collides with the side surface of the water from the 45 ° direction, there is little resistance caused by water flow. In addition, sediment flows on the upstream side of the block due to the water flow, and the sediment on the downstream side tends to be carried away by the water flow from below the foundation, but the sediment deposited on the upstream side is a vertical through-hole provided in the foundation. Since it moves to the lower surface of the base portion through the block, the stable state of the block can be maintained. Then, the four protrusions extending from the upper part of the main body to the surroundings are in a water flow and perform a wave-dissipating action.
[0014]
Further, in the fish nest block according to the present invention, the fish doorway that communicates the cavity in the main body with the outside world opens toward the downstream direction of the water flow, so that there is little carry-in into the cavity by the water flow such as earth and sand. And since the lowest edge of the entrance / exit is at the same height as the lower bottom surface of the cavity, the accumulated earth and sand are quickly carried out, so that the environment for growing fish can always be maintained well.
[0015]
And the block with a fish nest according to the present invention is manufactured in two parts, and the halves are combined later, which is convenient in terms of manufacturing and transportation.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of a fish nest block according to the present invention will be described with reference to the drawings. This fish nest block 11 is made of concrete, and is installed and used at the bottom of a river or water channel (hereinafter referred to as “river bottom”) 10 as shown in FIG. 5 or FIG. As shown in FIG. 1 and FIG. 2, the first block 12 and the second block 13 are formed, and one unit is formed by connecting the first block 12 and the second block 13 to each other. The fish nest block 11 is completed.
As shown in FIG. 1, the fish nest block 11 has a main body portion 14, and a base portion 15 is provided on the lower surface of the main body portion 14.
[0017]
As shown in FIG.1 and FIG.2, the main-body part 14 is a substantially rectangular parallelepiped external shape, and the hollow part 16 of the substantially rectangular parallelepiped as a fish nest is formed in the inside. As shown in the plan view of FIG. 3, the fish nest block 11 is divided into a first block 12 and a second block 13 by vertical dividing surfaces 17 and 18 passing through one diagonal line of the main body 14. ing. Of the two side walls (wall portions) 19, 20 formed in the first block 12, two circular fish doorways 21, 21 are vertically arranged on one side wall 19 on the front side. . Of the two side walls (wall portions) 22, 23 formed in the second block 13, the front side that is adjacent to the side wall 19 provided with the fish entrance / exit 21 of the first block 12 is provided. One side wall 22 is provided with two circular fish entrances 21, 21 arranged vertically. These four fish entrances 21 communicate with the cavity 16.
[0018]
As described above, the fish entrance / exit 21 is provided on the two side walls 19 and 22 on the front side adjacent to each other among the four side walls 19, 20, 22 and 23 of the main body 14, and not provided on the side walls 20 and 23 on the back side. As shown in FIG. 5, by installing this block 11 with a fish nest on the riverbed 10 in a predetermined direction so that the fish entrance 21 faces the river flow direction (downstream) 7, earth and sand and pebbles This is to prevent the water from flowing into the cavity 16 through the fish entrance 21 with the flow of water. This is because the river water does not vigorously flow into the cavity 16 through the fish entrance 21. Thereby, the outflow of fish eggs laid in the cavity 16 can be prevented.
[0019]
The lower edge 21 a of the lower fish entrance 21 of the two fish entrances 21 provided in each of the first and second blocks 12 and 13 is flat on the inner surface forming the cavity 16. are forms form the bottom surface 16a and substantially the same height. Thereby, even if earth and sand or the like may flow into the cavity 16, it can be discharged from the lower fish entrance 21.
Furthermore, the shape of the fish entrance / exit 21 is a circle, but it may be an ellipse that is long vertically or an oval so that the fish can easily pass therethrough.
[0020]
As shown in FIGS. 1 to 3, the base portion 15 is a plate-like body having a substantially square planar shape, and the lower portion of the main body portion 14 is coupled to the center portion of the upper surface. As shown in the plan view of FIG. 3, the dividing surfaces 17 and 18 passing through one diagonal line of the main body portion 14 pass through the center of the base portion 15 in parallel with one side of the base portion 15. Therefore, the main body portion 14 and the base portion 15 are coupled so that one diagonal line of the main body portion 14 is parallel to one side of the base portion 15.
By configuring in this way, by installing the block 11 with the fish nest on the riverbed 10 along the quay with the edge forming one side of the base portion 15 having a substantially square plane shape, the dividing surfaces 17 and 18 are arranged. The diagonal line of the main body part 14 through which the water passes can be made parallel to the flowing direction 7 of the river water. In this case, since the edge of the base portion 15 on the quay side can be along the quay, it can be installed with good appearance. And the flowing water collides with the side walls 20 and 23 on the river upper side of the main body portion 14 shown in FIG. 3, but the side walls 20 and 23 are inclined at an angle of about 45 ° with respect to the direction 7 of the water flow. It is possible to reduce the resistance of running water applied to the portion 14.
[0021]
And the concave part 24 with the shape of the upper opening edge being rectangular is provided on the inner upper surface of each of the four corners of the base part 15, and the base part 15 is provided at the center of each of the four concave parts 24. A circular through hole 25 penetrating in the vertical direction is provided. Each of the four through holes 25 has a size through which earth and sand can pass. As shown in FIG. 5, the four through holes 25 are installed on the riverbed 10, particularly on the lower side of the edge 15 a on the downstream side of the foundation portion 15. Even if the accumulated earth and sand and pebbles 26 may be scraped by running water, the earth and sand 27 in the through hole 25 and the earth and sand accumulated on the upper surface of the foundation portion 15 pass through each through hole 25 and the It is for entering into the shaved part, and thereby preventing a deep depression from being formed under the edge 15a on the downstream side of the base portion 15. As a result, the block 11 installed on the riverbed 10 can be prevented from tilting downstream.
[0022]
As shown in FIG. 1 and the like, a total of four protrusions 28 extending from the four corners to the outside in the horizontal direction are provided on the upper portion of the main body 14. The four protrusions 28 serve to quench the wave, and as shown in FIG. 5, the four protrusions 28 are installed on the riverbed 10 so that the upper portion thereof is exposed from the surface of the layer 29 of the chestnut 5.
[0023]
Further, as shown in FIG. 2A, a protrusion 30 is provided on the lower edge of the dividing surface 17 of the first block 12, and a protrusion 31 is provided in the center of the protrusion 30. . Then, as shown in FIG. 2B, a groove 32 and a fitting recess 33 are provided on the lower edge of the dividing surface 18 of the second block 13 so that the protrusion 30 and the protrusion 31 can be fitted. It is.
As shown in FIG. 2, the total four protrusions 28 a, 28 a, 28 b, 28 b on which the divided surfaces 17, 18 of the first and second blocks 12, 13 are formed have the divided surfaces 17, 18. One insertion hole 34 for the bolt 35 is provided in a direction perpendicular to each other. Further, the protrusion 31 is provided with an insertion hole 37 of the bolt 36 in a direction parallel to the dividing surface 17, and the inner surface of the fitting recess 33 corresponds to the insertion hole 37 provided in the protrusion 31. An insertion hole 38 is provided at the position. A nut for screwing into the bolt 36 is embedded in the insertion hole 38.
[0024]
When the first and second blocks 12 and 13 are joined to complete the fish nest block 11, first, as shown in FIGS. 3 and 4, the protrusions 30 and the protrusions 31 of the first block 12. Are fitted into the groove 32 and the fitting recess 33 of the second block 13 to align the respective divided surfaces 17 and 18. As a result, the corresponding ones of the insertion holes 34, 34, 37, 38 of the first and second blocks 12, 13 can be aligned with each other on the same axis. Then, the bolts 35 and 36 are inserted into the respective insertion holes 34, 34, 37 and 38, and the first and second blocks 12 and 13 are sandwiched and tightened by the bolts and nuts. Thus, the fish nest block 11 can be completed.
By the protrusions 30 and the grooves 32, the relatively heavy first and second blocks 12 and 13 can be easily aligned in the vertical direction. Then, the convex portion 31 and the fitting concave portion 33 can easily perform alignment in the horizontal direction parallel to the dividing surfaces 17 and 18 of the first and second blocks 12 and 13.
[0025]
Further, as shown in FIG. 3, a total of eight insertion holes 39 penetrating horizontally from the inner side surfaces of the four concave portions 24 provided in the base portion 15 to the outer side surface of the edge portion of the base portion 15 are provided. It is. Two insertion holes 39 are provided at each of the four edges of the base portion 15. As shown in FIG. 6, each insertion hole 39 is arranged in a state where the blocks 11 with fish nests are horizontally arranged at substantially the same height and are arranged so as to abut against the edge of the base portion 15. The bolts 40 are respectively inserted into the respective insertion holes 39 provided in the, and the adjacent fish nest blocks 11 and 11 are connected to each other by the bolts 40 and nuts. In this way, by connecting the adjacent fish nest blocks 11 and 11 with the bolts 40, the positional relationship between the blocks can be prevented from being shifted by the flow of water.
[0026]
The fish nest block 11 configured as described above has a plurality of fish nest blocks 11 (one is shown in FIG. 5) spaced apart from each other as shown in FIG. 5, for example. The four fish entrances 21 provided in each fish nest block 11 can be installed and used on the riverbed 10 in a state in which they face the river flow direction (downstream direction) 7. In FIG. 5, 41 is a layer of earth and sand and pebbles, and 29 is a layer of chestnut stone 5. A portion including the base portion 15 below the two fish entrances 21 of the fish nest block 11 is embedded in a layer 41 such as earth and sand, and the upper portions of the four protrusions 28 are from the surface of the layer 29 of the chestnut stone 5. Exposed. The gap between the chestnut stones 5 is a dimension that allows fish to pass through, and the fish can enter the hollow portion 16 through the gap and enter the hollow portion 16 from the fish entrance / exit 21 provided in the main body portion 14.
[0027]
According to this fish nest block 11, some of the earth and sand and pebbles carried from the river by running water are located on the downstream side along the two side surfaces 20 and 23 of the fish nest block 11 on the river upper side. As a result, it is possible to reduce the force of earth and sand pushing the block 11 with the fish nest downstream. On the other hand, the earth and sand in the vicinity of the side surfaces 19 and 22 on the downstream side of the block 11 with the fish nest are carried to the downstream side by flowing water whose speed has been increased by increasing the water, for example, and a recess 42 is formed in that portion. Although the depth of 42 may reach the lower surface of the base portion 15, earth and sand in the through-hole 25 provided in the base portion 15, and earth and sand deposited on the upper surface of the base portion 15 are the through-hole 25. It passes through and enters the lower surface of the base portion 15, thereby making it possible to prevent a deep depression from being formed in the downstream side portion of the lower surface of the base portion 15. As a result, it is possible to prevent the block 11 installed on the riverbed 10 from tilting downstream.
[0028]
Since the fish nest block 11 is formed by joining the first and second blocks 12, 13, the bulk of each block 12, 13 is smaller than the completed fish nest block 11. As a result, the manufacture is easy, and when the block 11 with the fish nest is installed, the blocks 12 and 13 can be transported and constructed relatively easily.
[0029]
The fish nest block 11 is composed of the first block 12 and the second block 13 which are divided by the dividing surfaces 17 and 18 passing through the cavity 16, so that the first and second blocks The main body portion 14 having the hollow portion 16 can be relatively easily manufactured by separately manufacturing 12 and 13 and connecting them. And since the main-body part 14 is divided | segmented by the vertical division surfaces 17 and 18 which pass the cavity part 16, when the block 11 with a fish nest is installed in the riverbed 10, the air in the cavity part 16 is from this mating surface. The water flows out into the cavity 16 and can effectively function as a fish dwelling house.
[0030]
And when the block 11 with a fish nest is installed in the riverbed 10, the air contained in the earth and sand below the foundation part 15 works as a buoyancy in the direction of lifting the block 11 with the fish nest. It is possible to escape upward from the lower surface of the base portion 15 through the four through holes 25 provided in the portion 15, and also upward from the gap between the dividing surfaces 17 and 18 of the first and second blocks 12, 13. Thus, the stability of the installed fish nest block 11 can be ensured. Further, a part of the river water flows in the earth and sand below the foundation portion 15 and acts as a force in the direction of lifting the block 11 with the fish nest, but this running water is also upward from the lower surface of the foundation portion 15 through each through hole 25. Since it can be released upward from the gap between the dividing surfaces 17 and 18 of the first and second blocks 12 and 13, the stability of the block 11 with the fish nest can be ensured.
It should be noted that the air on the dividing surfaces 17 and 18 of the first and second blocks 12 and 13 can be more efficiently released to the upper side of the fish-nest block 11 with the air and running water below the base portion 15. In addition, a water escape groove (not shown) may be provided.
[0031]
Furthermore, as shown in FIG. 6, in a state where two or more fish nest blocks 11 are horizontally arranged at substantially the same height, the edges of the adjacent base portions 15 come into contact with each other so that the base portions 15 Since the sediment deposited on the lower side is covered, the sediment deposited below the foundation portion 15 can be prevented from flowing into the water. As a result, the layer such as earth and sand under the base portion 15 can be prevented from being depressed, so that the fish nest block 11 can be prevented from inclining.
Among the plurality of fish nest-attached blocks 11 that are installed, those installed at the end portion are adjacent to layers such as earth and sand that are not covered by the base portion 15, so The earth and sand on the lower surface of the foundation portion 15 of the fish nest block 11 installed at this end portion may be washed away by water, but the earth and sand accumulated on the upper surface of the foundation portion 15 is provided on the foundation portion 15. The bottom surface of the base portion 15 is entered through the through-holes 25 that are formed, so that no depression can be made in the earth and sand on the bottom surface of the base portion 15.
[0032]
Incidentally, the height of the block 11 with the fish nest is about 85 cm, the horizontal length and depth of the base portion 15 are about 100 cm, the diameter of the fish entrance / exit 21 is about 10 cm, the diameter of the through hole 25 is about 16 cm, and the bolt 35 , 36, 40 have a nominal diameter of 10 mm. And the weight of the block 11 with a fish nest is about 630 kg.
[0033]
However, in the above-described embodiment, the outer shape of the main body portion 14 is a substantially rectangular parallelepiped, but may be a shape other than this, for example, the outer shape may be a cylinder or a polygonal column.
And in the said embodiment, as shown in FIG. 5, although it was set as the structure which provided the two through-holes 25 in the river upper side and downstream side of the base part 15 on the basis of the main-body part 14, It is good also as a structure which abbreviate | omitted the through-hole 25. FIG.
Moreover, although the example which installed the block 11 with a fish nest in the riverbed 10 was shown in the said embodiment, you may install in the seabed. In this case, like the one shown in FIG. 5 and FIG. 6, the fish nest block 11 is installed so that the fish entrance / exit 21 faces the direction in which the seawater flows.
Furthermore, in the said embodiment, although the example which divided | segmented the block with a fish nest into the 1st and 2nd two blocks 12 and 13 was shown, in order to attain simplification of manufacture, and simplification of conveyance and construction, It is good also as a structure divided | segmented into three or more blocks.
[0034]
【The invention's effect】
As described above, the block with a fish nest according to the present invention has a good posture stability in a water stream, can maintain a good growth environment for fish, and can be manufactured in a divided state. It is also advantageous in terms of transportation.
[Brief description of the drawings]
FIG. 1 is a front perspective view of a fish nest block according to an embodiment of the present invention.
FIG. 2A is a perspective view showing an inner surface of a first block according to the embodiment, and FIG. 2B is a perspective view showing an inner surface of a second block according to the embodiment.
FIG. 3 is a plan view of a fish nest block according to the embodiment;
FIG. 4 is a front view of the fish nest block according to the embodiment.
FIG. 5 is a partially cutaway side view showing a state where blocks with fish nests according to the embodiment are installed one by one at intervals.
FIG. 6 is a side view showing a state in which a plurality of blocks with fish nests according to the embodiment are connected and installed.
FIG. 7 is a perspective view of a state in which a plurality of conventional cross blocks are connected and installed as viewed obliquely from above.
8 is a side view showing a state in which one of the conventional cross blocks shown in FIG. 7 is installed. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 River bottom 11 Block 12 with a fish nest 1st block 13 2nd block 14 Main body part 15 Base part 16 Cavity part 17, 18 Dividing surface 21 Fish entrance / exit 25 Through-hole 30 Projection 31 Projection 32 Groove 33 Fitting recessed part

Claims (8)

And cuboid body having a cavity as Sakanasu therein, the entrance of fish for communicating the said cavity and the outside respectively provided on the side wall facing the downstream direction of the water or sea water flow of the body, said body A substantially square base portion extending in a substantially horizontal direction around the periphery and having an edge substantially parallel to the diagonal of the main body, and downstream of the water or seawater flow of the base portion A fish nest block, characterized in that a vertical through-hole that allows passage of earth and sand is formed in a portion in the direction. The block with a fish nest according to claim 1 , wherein a vertical through-hole through which earth and sand can pass is also formed in the upstream portion of the water or seawater flow of the foundation. Block with fish nest. 2. The fish nest block according to claim 1 , wherein a protrusion parallel to the peripheral edge of the base portion extends in four directions from the upper part of the main body . In serial mounting of fish nests with blocks in claim 1, the lowermost edge of the doorway of the fish, fish nests with blocks, characterized in that the bottom surface and substantially the same height of the cavity. 2. The fish nest block according to claim 1 , wherein the main body and the base portion are connected to each other at the dividing plane by the first and second block halves divided by a vertical dividing plane passing through a diagonal line of the main body. A block with a fish nest characterized by being assembled. 6. The fish nest block according to claim 5 , wherein a convex portion is provided on the dividing surface of the first block half, and the dividing surface of the second block half is complementary to the convex portion. A block with a fish nest characterized by providing a recess that can be joined. In fish nest with blocks of claim 1 wherein, the connector for preventing the positional relationship between each other is lost each in a state where the plurality is peripheral edges of each of the base portion was placed side by side with each other in contact with one A block with a fish nest characterized by being provided between the bases . In fish nest with blocks according to claim 1, characterized in that the plurality of side by side at the periphery are in contact with each other to each other relationship each foundation was placed was embedded the foundation in soil of the riverbed or seabed A block with a fish nest.

Images