JP2709430B2 - Fish nest block - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a block used for revetment of a waterway such as a river or an artificial canal, a head work, etc.
The present invention relates to a fish nest block suitable for aquatic organisms such as fish, shellfish, and crab.

[0002]

2. Description of the Related Art The following are known as seawalls or head works using conventional fish nest blocks. (1) As described in Japanese Utility Model Laid-Open No. 1-90821, a square box-shaped fish nest block having an internal space surrounded by a wall with an opening is used, and the fish nest block is placed on a slope of a waterway. A seawall with fish nests, which are simply stacked along the front and these fish nest blocks are lined up like a single wall.

(2) As described in Japanese Utility Model Application Laid-Open No. 59-69226, an inclined plate along the slope of a water channel, a vertical wall provided at the rear end thereof, and a horizontal wall extending forward from the upper end of the vertical wall. A fish nest block consisting of a protruding horizontal wall and a space between them is used so that the rear end of the inclined plate of this fish nest block is in contact with the front end of the inclined plate of the next fish nest block. A seawall with fish nests in which the horizontal walls are arranged stepwise by lining up the slopes of waterways.

(3) As described in Japanese Utility Model Laid-Open Publication No. 3-79325, a flat rectangular base, a rear vertical wall and a front vertical wall standing on a rear edge and a front edge, and an upper end of the rear vertical wall. A fish basin formed by using fish nest blocks consisting of horizontal walls continuously provided in a waterway and burying these fish nest blocks in a waterway at intervals.

[0005]

However, the conventional fish nest has the following problems. First, in the revetment with a fish nest described in (1) above, the fish nest is formed inside the fish nest block surrounded, and the shape is quite different from the natural depression, and the internal water is not circulated much. It was difficult to find the best environment for living creatures. In addition, there is also a problem that since the fish nest is hardly exposed to direct sunlight, the water temperature is hardly increased, and the growth of underwater plants such as aquatic plants and algae, which are preferable for aquatic organisms, is poor.

In the seawall with a fish nest of the above (2), the fish nest is formed in the space between the inclined plate and the vertical wall and the horizontal wall of the fish nest block, and particularly, the upper surface of the inclined plate is inclined. Therefore, there is a problem that it is not possible to lay gravel, chestnut stone or cobblestone which is preferable for habitation of fish or the like on this upper surface. In addition, there is a problem that the fish nest block must be manufactured each time the slope angle is adjusted to a different slope angle for each water channel.

In the fish pit of the above (3), the fish nest is formed in a gutter shape by the base of the fish nest block, the left vertical wall and the right vertical wall. 2) The problem with fish nests is improved. However, since no escape route for aquatic organisms was provided anywhere in this fish nest block, there was a problem that the aquatic organisms were trapped in the fish nest when the amount of flowing water in the river was significantly reduced.

Accordingly, an object of the present invention is to form a fish nest close to nature suitable for inhabiting aquatic organisms such as fish, shells and crabs by using it for revetment of a water channel, head work, etc.
It is an object of the present invention to provide a new fish nest block that allows aquatic organisms to escape from the fish nest when the water flow in the canal is significantly reduced.

[0009]

To achieve the above object, according to the Invention The fish nest block of the present invention includes a bottom plate, and erected a vertical wall in the rear edge of the bottom plate, vertically middle portion of the bottom plate Away from the wall
And a support wall which stands up in an isolated state .

In this fish nest block, a receiving wall extending in the left-right direction may be erected at the front edge of the bottom plate, and an escape path for aquatic organisms may be formed in a part of the receiving wall. In addition, it is preferable that at least one vertical surface of the vertical wall or the support wall is an inclined surface (Claim 3), and that a through hole is formed in the bottom plate (Claim 4). The support wall may be formed integrally with the bottom plate, or may be formed separately from the bottom plate and attached to the bottom plate.

It is preferable that at least a part of the surface is provided with irregularities (claim 6). A plurality of convex portions or concave portions are integrally formed on the upper surface of the bottom plate. Attach multiple projections to the top of the bottom. The bottom or the receiving wall or the attachment to them are formed of permeable concrete having irregularities.
Since a part of the base and the receiving wall do not receive as much load as the vertical wall and the supporting wall, there is no problem in strength even if they are formed of permeable concrete. When the base is made of permeable concrete, it is preferable to use a reinforcing bar made of carbon, synthetic resin, stainless steel or the like which does not rust.

[0012]

The fish nest blocks according to the first aspect can be piled up to construct revetments, head works and the like. When stacking, on the vertical wall of the lower fish nest block and the upper surface of the support wall,
The bottom plate of the upper fish nest block can be placed and supported. By changing the relative position of the upper and lower fish nest blocks in the front-rear direction, it is possible to cope with seawalls, head works and the like having different slopes.

Further, a fish nest close to nature suitable for aquatic organisms such as fish, shellfish and crab is formed for the following reasons. First, a fish nest with a shallow dent close to nature is formed on the upper surface of the bottom plate. The support wall is separated from the vertical wall in the middle of the bottom plate and isolated
It is built up in
The area is large because there is little risk of giving
The fish nest can be formed openly. On the upper surface of this base, gravel, chestnut stone or cobblestone (the size increases in this order)
Can be laid individually or in combination at a uniform height or in an uneven shape. From the viewpoint of giving a change to the fish nest, it is preferable to lay unevenly by combining gravel, chestnut stone or cobblestone.

In addition, since direct sunlight is appropriately applied to the fish nest from above the front edge of the bottom plate, the water temperature rises moderately, and
Creates a good environment for the growth of underwater plants such as algae. Also, since the shade is appropriately formed below the support wall, a favorable environment for resting aquatic organisms and the like is formed. In addition, the fish nest has a very good circulation of water, thus creating an environment rich in oxygen and nutrients.

Furthermore, since there is no barrier for aquatic organisms to pass through the front edge of the bottom, the aquatic organisms can freely pass above the front edge of the bottom when the amount of flowing water in the water channel is significantly reduced. Can easily escape from

Further, according to the fish nest block of the present invention, the receiving wall prevents gravel, chestnut stone or cobblestone laid on the bottom from spilling forward, so that the environment of the fish nest is stabilized. In addition, since an escape route for aquatic organisms is formed in a part of the receiving wall, when the amount of flowing water in the water channel is significantly reduced, the aquatic organisms can escape from the fish nest through the escape route.

According to the fish nest block of the third aspect, since the vertical wall or the supporting wall is provided with the inclined surface, the aquatic organisms, particularly the crab, the crayfish, the hermit crab, etc., are different from the case where only the vertical surface is provided. Makes it easier for arthropods to climb and descend. Furthermore, according to the fish nest block of the fourth aspect, since the bottom hole is formed with a through hole for aquatic organisms, aquatic organisms, for example, arthropods climbing up and down the inclined surface pass through the through hole and upper and lower stages. Can be easily moved between.

According to the fish nest block of the present invention, since the support wall is formed separately from the bottom plate, when the fish nest block is formed, the shape is simplified by the absence of the support wall.
The design and removal of the mold are facilitated.

Further, according to the fish nest block of the present invention, since at least a part of the surface is made uneven, the surface area of the fish nest increases, and the fish nest block approaches a natural riverbed state. Therefore, a fish nest close to nature suitable for inhabiting aquatic organisms can be formed without laying or reducing the amount of gravel, chestnut stone or cobblestone. In addition, when walking along a water channel, it is difficult to slip on the upper surface of the bottom plate, so that a slip-down accident can be prevented. Further, according to the fish nest block of the present invention, since the bottom or the receiving wall or the attachment to the bottom or the receiving wall is formed of uneven permeable concrete, supply of oxygen and nutrients is improved by its porosity. .

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A fish nest block according to a first embodiment of the present invention will be described below with reference to FIGS. This fish nest block 1 is formed into a shape as shown in FIG. 1 by concrete in which a reinforcing bar is buried, and the thickness of each part is 200 mm. In addition, the dimensions of each part described below are examples, and can be appropriately changed.

The fish nest block 1 has a horizontal bottom plate 2 formed in the shape of a square plate, the left end surface and the right end surface of the bottom plate are inclined downward, and the length of the bottom surface in the left-right direction is 180.
0mm, width in the front-back direction is 2000mm, thickness is 200m
m. A vertical wall 3 extending in the left-right direction is provided at the rear end of the base 2.
Is erected integrally and its length in the left-right direction is 2000m
m, the height from the bottom of the bottom plate is 1000 mm.

A pair of support walls 4 are integrally formed at the center of the left edge and the right edge of the bottom plate 2 and are separated from the vertical wall 3.
Erected on an isolated form Te, the height from the bottom plate upper surface 800
mm. The opposing surfaces of the two support walls 4 are inclined surfaces 4a, and the gradient (expressed by a horizontal distance when the height is 1; hereinafter the same) is 5 minutes. By extending this inclined surface 4a downward, a through hole 8 is formed in the center of the bottom plate 2.
Is pierced.

At the front edge of the bottom plate 2, a receiving wall 5 having a trapezoidal shape extending downward and extending in the left-right direction is integrally erected,
The length of the upper surface in the left-right direction is 800 mm, and the height from the upper surface of the bottom plate is 800 mm. Therefore, the left and right side surfaces of the receiving wall 5 are inclined surfaces 5a having a gradient of 5 minutes, and a left and right escape path 6 is formed on the left and right sides of the receiving wall 5 so as to widen upward. At the center of the receiving wall 5, a through hole 9 is formed continuously through the upper surface of the bottom plate 2 to form a tapered hole extending forward.

The receiving wall 5 is not shown in FIG. 4 except for the embodiment shown in FIG.
(Or the chain line in FIG. 4), the height is reduced.

A plurality of flat ridges 10 extending in the left-right direction are integrally formed at intervals on the lower surface of the bottom plate 2, and the upper surfaces of the vertical wall 3 and the support wall 4 are fitted between them. A fitting recess 11 having a width of 250 mm is formed.

Now, using the fish nest block 1 of the present embodiment, a seawall with fish nests as shown in FIG. 2 can be constructed. That is, Kuriishi 1 is placed on the lower upper surface of the slope 15 of the waterway.
6 is laid, and a discarded concrete 17 is cast on the chestnut stone 16. A plurality of fish nest blocks 1 are placed and arranged on the upper surface of the discarded concrete 17 with the rear surface of the vertical wall 3 facing the slope 15, and gravel, chestnut stone or cobble stone (hereinafter, chestnut stone) is placed on the upper surface of the bottom plate 2. 18 is used alone or in combination to be laid at a uniform height or in an uneven shape to form the first stage. At a position shifted backward from the first stage, a second stage is formed in a similar manner, and further a third stage is formed. Since the lower vertical wall 3 and the support wall 4 are fitted into the upper fitting concave portion 11, displacement of the upper and lower fish nest blocks 1, particularly displacement in the front-rear direction, is reliably prevented.

Further, using the fish nest block 1 of the present embodiment, a head nest with a fish nest as shown in FIG. 3 can be constructed. That is, a step-like concrete base 14 is cast on the step portion of the riverbed 13 so as to extend in the transverse direction of the river. A plurality of fish nest blocks 1 are placed and arranged on the upper surface of each step of the concrete base 14 with the rear surface of the vertical wall 3 facing upstream, and chestnuts and the like 18 are laid on the upper surface of the bottom plate 2. Thereby, the first stage, the second stage, and the third stage are formed.

In the revetment or head work, the second and third fish nest blocks 1 are sufficiently stabilized by their own weight.
Further, when riverbed scouring, land subsidence, or the like occurs, the connection between the fish nest blocks 1 can be kept flexible. Further, as shown in FIG. 3, an anchor reinforcement 19 which projects rearward is fixed to the Sakanasu block 1 is embedded in the concrete foundation 14, it is preferable to prevent the displacement of Sakanasu block 1 by earth pressure and flow pressure .

The upper fish nest block 1 may be stacked directly above the lower fish nest block 1 or in a staggered manner. The upper and lower fish nest blocks 1
By changing the relative position in the front-rear direction, the slope of the revetment or the head drop can be easily changed.

Since the fish nest block of the present embodiment is configured as described above, the following actions and effects are obtained. (1) From the following reasons, a fish nest close to nature suitable for inhabiting aquatic organisms such as fish, shellfish, and crab can be formed over a wide area. A shallow and wide depression surrounded by the vertical wall 3 and the receiving wall 5 is formed on the upper surface of the bottom plate 2 of the fish nest block 1, and this depression forms a fish nest close to nature. Moreover, the support wall 4 is separated from the vertical wall 3
Standing in isolation, the area is large
In addition, an open fish nest can be formed. And since this fish nest is formed for each fish nest block 1 of each stage, the total area becomes very large.

Since the upper surface of the bottom plate 2 is horizontal, it is possible to lay the stones 18 or the like at a uniform height or unevenly as described above. Since the receiving wall 5 prevents the stilt 18 and the like 18 from falling forward, it is held on the upper surface of the bottom plate 2. The thus-retained chestnut stone 18 forms a favorable environment for aquatic life activities, spawning and the like.

[0032] Since direct sunlight is appropriately applied to the fish nest from above the front edge of the bottom, the water temperature is appropriately increased, and an environment favorable for the growth of underwater plants such as aquatic plants and algae is formed. Since a suitable shade is formed below the support wall 4, a favorable environment for resting aquatic organisms is formed. Since the fish nest is a shallow depression along the water stream, the water circulation is very good and creates an environment rich in oxygen and nutrients.

(2) Since an escape passage 6 is formed between the adjacent receiving walls 5 in the front-rear direction, when the amount of flowing water in the river is significantly reduced, aquatic organisms escape from the fish nest.
To escape to the lower fish nests or waterways.

(3) Further, according to the embodiment having no receiving wall as shown in FIG. 4 or the embodiment in which the height of the receiving wall 5 is reduced as shown in FIG. When the water is reduced, the aquatic organisms can freely pass over the front edge of the bottom plate 2 and easily escape, and driftwood, dust and the like do not catch on the front edge of the bottom plate 2 and are not easily deposited.

(4) Since the opposing surface of the support wall 4 and the side surface of the receiving wall 5 are inclined surfaces 4a, 5a, nodes such as crabs, crayfish, hermit crabs, etc. are compared with the case where only the vertical surface is used. It is suitable for foot animals to climb and descend, creating an environment where they can easily work.

(5) In addition, since through holes 8 and 9 are formed through the bottom plate 2 and the receiving wall 5, arthropods climbing up and down the vertical wall 3, the supporting wall 4 or the receiving wall 5, and others. The aquatic creatures easily move through the upper and lower fish nest blocks 1 through the through holes 8 and 9, and an environment suitable for activities such as arthropods is formed. The through hole 9 also functions as an escape route in the front-rear direction.

Next, in the fish nest block 21 of the second embodiment shown in FIG. 5, a blocking wall 22 extending in the front-rear direction and a support wall 23 in the shape of a truncated octagonal pyramid are integrally formed at the center of the upper surface of the bottom plate 2. This is different from the first embodiment. All side surfaces of the support wall 23 are inclined surfaces 23a. According to the present embodiment, the movement of the rock stone or the like laid on the bottom plate 2 in the left-right direction can be prevented by the blocking wall 22, so that the environment of the fish nest is further stabilized.

Next, in the fish nest block 31 of the third embodiment shown in FIGS. 6 and 7, a closing wall 32 is integrally formed on the left edge and the right edge of the upper surface of the bottom plate 2 while the cross section is gate-shaped. The support wall member 33 is formed separately from the bottom plate 2, and the fitting recess 35 formed on the lower surface of the support wall member 33 is fitted into the fitting recess 34 formed on the upper surface of the blocking wall 32. The configuration is different from that of the first embodiment. That is, as shown in FIG. 6, the support wall member is provided so as to straddle two adjacent blocking walls 32 of the row of fish nest blocks 31.
33 is lowered and fitted as shown in FIG.
Adjacent fish nest blocks 31 may be arranged without gaps as shown in FIG. 6, or may be provided with a gap up to about 100 mm as shown in FIG.

According to the present embodiment, when the fish nest block 31 is formed, the shape is simplified by the absence of the support wall on the bottom plate 2, and the design and removal of the mold are facilitated. Further, the support wall member 33 exhibits not only the function of supporting the fish nest blocks, but also the function of connecting the adjacent fish nest blocks, and the function of changing the fish nests by making the bottom plate uneven.

Next, in the fish nest block 41 of the fourth embodiment shown in FIG. 8, a blocking wall 42 extending in the front-rear direction and a support wall 43 extending in the left-right direction are integrally formed at the center of the upper surface of the bottom plate 2. A large number of truncated quadrangular pyramid-shaped protrusions 4
The fourth embodiment differs from the first embodiment in that the bottom plate 2 is made uneven by integrally forming the bottom plate 4. According to the present embodiment, in addition to the same effect as the second embodiment, the surface area of the fish nest increases and approaches the state of a natural riverbed. Nearly natural fish nests suitable for aquatic organisms are formed. In addition, when walking on a water channel, the upper surface of the bottom plate 2 is hardly slipped, so that a slip-down accident can be prevented.

A part of a fish nest block, for example, a receiving wall
Is made of uneven permeable concrete and the rest
Can be formed by ordinary concrete. The porosity of permeable concrete improves the supply of oxygen and nutrients.

Note that the present invention is not limited to the configuration of the above-described embodiment, and can be embodied by appropriately changing without departing from the spirit of the invention.

[0043]

The fish nest block according to claim 1 or 2,
Since it is configured as described above, it can be used for seawall protection, head work, etc. to form fish nests close to nature suitable for the inhabitation of aquatic organisms such as fish, shellfish, crabs, etc. When the amount of flowing water is significantly reduced, it has an excellent effect that aquatic organisms can escape from the fish nest.

According to the fish nest block of the third or fourth aspect, the activity of aquatic organisms, particularly arthropods such as crabs, crayfish, and hermit crabs can be assisted.

According to the fish nest block of the fifth aspect, when the fish nest block is formed, the design and removal of the mold are facilitated.

According to the fish nest block of the present invention, a fish nest close to nature suitable for inhabiting aquatic organisms can be obtained without laying or reducing the amount of gravel, chestnut stone or cobblestone. As well as being formed, it is possible to prevent a slide-down accident during walking in a waterway. Further, according to the fish nest block of the seventh aspect, the supply of oxygen and nutrients is improved by the porosity of the permeable concrete.

[Brief description of the drawings]

FIG. 1 is a perspective view of a fish nest block according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a seawall with a fish nest constructed by the fish nest block.

FIG. 3 is a sectional view of a head with a fish nest constructed by the fish nest block.

FIG. 4 is a perspective view of a modified example of the fish nest block.

FIG. 5 is a perspective view of a fish nest block according to a second embodiment.

FIG. 6 is an exploded perspective view of a fish nest block according to a third embodiment before assembly.

FIG. 7 is a perspective view after the fish nest block is assembled.

FIG. 8 is a perspective view of a fish nest block according to a fourth embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Fish nest block 2 Bottom board 3 Vertical wall 4 Support wall 5 Receiving wall 6 Escape way 8 Through hole 9 Through hole 21 Fish nest block 23 Support wall 31 Fish nest block 33 Support wall member 41 Fish nest block 43 Support wall 44 Convex part

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-62-160310 (JP, A) JP-A-3-55307 (JP, A) JP-A-1-90821 (JP, U)

Claims (7)

(57) [Claims] 1. A fish nest comprising a bottom plate, a vertical wall provided upright on a rear edge of the bottom plate, and a support wall provided upright in the middle of the bottom plate so as to be separated from the vertical wall. block. 2. The fish nest block according to claim 1, wherein a receiving wall extending in the left-right direction is erected at a front edge portion of the bottom plate, and an escape route for aquatic organisms is formed in a part of the receiving wall. Wherein the longitudinal wall or at least one Sakanasu block according to claim 1 or 2, wherein elevation is an inclined surface of the supporting wall. 4. Sakanasu block according to claim 1, wherein the through holes of the bottom plate to aquatic organisms has been formed. 5. The supporting walls, the bottom plate is separate form, according to claim 1, 2, 3 or 4 Sakanasu block according those attached to the bottom panel. 6. At least Sakanasu block some to claim 1, 2, 3, 4 or 5, wherein the irregularities attached surface. 7. The fish nest block according to claim 6, wherein the bottom plate, the receiving wall, or the attachment to the bottom plate or the receiving wall are formed of permeable concrete having irregularities.