JP5330216B2 - Artificial reef - Google Patents

Description

  The present invention relates to improving the stability of an artificial reef having a collection space inside.

  The conventional fishing ground construction has achieved certain results with the main purpose of collecting and protecting and fostering fish by installing structures such as bottomed fish reefs, breeding reefs, and floating fish reefs on the sea floor. However, overfishing due to the development of fishing methods has led to a decrease in resources. Recently, upwelling facilities aiming at resource recovery have attracted attention.

  Fish reefs, which mainly have the effect of so-called upwelling currents that flow from the sea floor toward the sea surface, push up nutrient salts such as phosphates and nitrates to the upper layers where sunlight reaches, thereby promoting the photosynthetic action of plankton. It is effective to promote growth and to form a food chain of small fish that feeds on this plankton, middle fish that feeds on small fish, and large fish, and obtain a good fishing ground. A mound fish reef (for example, Patent Document 1) that forms a mountain-shaped obstacle on the seabed is currently used to make the horizontal current of the ocean current or tidal current as a vertical upwelling current.

  As this mound fish reef, for example, coal ash discharged from a thermal power plant or the like is solidified with concrete to form a rectangular concrete molded body, and this concrete molded body has a length of several tens to several hundred meters and 2 to 2 on the sea floor. These mound fish reefs are stacked up to a height of 30 meters, and contribute to the growth of fish and the like as described above by causing upwelling currents. Since it was not provided, it was not necessarily suitable for fish habitat. Moreover, since coal ash is used, it cannot be said that there is no influence on the environment.

  The height of the mound's mountain is necessary to cause upwelling on the mound reef. Throwing stones, etc. to build a mountain in a large depth of about 100 meters is inaccurate, it is extremely difficult to build a high mountain, and the construction period is long and the cost is high. In addition, the more efficient the mountain is built and the greater the upwelling effect, the faster the tidal flow velocity at the top of the mountain and the risk of collapse of the top block due to fluid forces.

JP-A-56-99736

  Applying a face material to an artificial reef made of a framework structure to enhance the upwelling effect of the upwelling facility will increase the fluid force applied to the reef by waves and tides, resulting in poor stability of the artificial reef such as sliding and falling. .

  In addition, as for existing artificial fish reefs, face members, tubular members, and the like are attached as reinforcing members to improve the fish collection effect, and the functions of the fish reefs are improved, but the stability of the fish reefs deteriorates.

  Therefore, in view of the above-described problems, the present invention provides an artificial fish reef that can improve the safety of sliding and falling against waves and tides of an artificial fish reef equipped with an auxiliary member and an artificial fish reef provided with upwelling function. The purpose is to provide.

The invention according to claim 1 is an artificial fish reef provided on the sea bottom of sandy ground, and has a vertical and horizontal beam material and a collection space inside, and a fish reef body provided at the bottom of the fish reef body and extending outside the fish reef body. And a reinforcing diagonal member is provided between the overhanging portion and the fish reef body, and the fish reef body has a height that is 1.5 times or more the width of the bottom, and the overhanging portion Is provided with a box-shaped portion having a face member provided around the bottom part and a wall part provided on the face member .

  According to the configuration of the first aspect, the artificial fish reef placed on the sea floor is vibrated by the influence of a large wave or a fast tidal current, and receives a rising force with one side of the frame as an axis and the other side floating upward. On the other hand, when the bottom part is expanded by the frame material that is the overhanging part, the turning radius becomes large, and the safety of the reef toppling is increased. In addition, when the overhang is a face material, it is in close contact with the sand and mud on the seabed, and when the face material is going to rise, the pressure between the face material and the sea floor is reduced, increasing the stability of the reef toppling, and the reef. Sand and mud accumulates on the face material due to repeated scouring and embedding of the surrounding seabed and becomes a load, preventing the fall of the fish reef and stabilizing it. Moreover, in the case of the frame member to which the projecting portion is provided with the face material, the rising pressure of the frame member is suppressed by seawater, and the safety of the reef toppling is increased.

  Moreover, according to the structure of Claim 1, the intensity | strength of an overhang | projection part increases and is stabilized by a reinforcement diagonal.

  Moreover, according to the structure of Claim 1, the stabilization can be aimed at in the artificial reef in which the ratio of height is larger than width. Furthermore, the stability of the artificial reef can be improved.

Moreover, according to the structure of Claim 1 , a box-shaped part is formed by providing a wall part in the inner periphery and outer periphery of a face material, the scouring sand mud accumulates in this box-shaped part, There is an effect of further improving the fall stability. Furthermore, the periphery of the fish reef body is repeatedly scoured and buried by waves and tidal currents, so that the periphery of the fish reef becomes a mortar shape and the sliding of the fish reef is suppressed.

It is sectional drawing of the installation state which shows the reference example 1 of this invention. It is sectional drawing in the middle of installation same as the above. It is a top view of a fish reef main body same as the above. It is a top view of a frame part same as the above. It is sectional drawing of the installation state which shows the reference example 2 of this invention. It is a top view of the frame part provided with face material same as the above. It is sectional drawing of the principal part of the installation state which shows Example 1 of this invention.

Preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.
The embodiments described below do not limit the contents of the present invention described in the claims. In addition, all of the configurations described below are not necessarily essential requirements of the present invention. In each embodiment, an artificial fish reef which is not conventional is obtained by adopting an artificial fish reef different from the conventional one, and the artificial fish reef is described respectively.
[Reference Example 1 ]

Hereinafter, an artificial fish reef of the present invention will be described with reference to the accompanying drawings. 1 to 4 show Reference Example 1 of the present invention. As shown in FIG. 1, an artificial fish reef 1 is made of steel which is a fish reef body in which a horizontal beam member 3 and a vertical beam member 4 made of steel are assembled in three dimensions. The frame body 5 is provided. A plurality of storage frame portions 6 that are collection spaces adjacent to each other in the vertical and horizontal directions are formed inside the frame body 5, and the storage frame portions 6 have water permeability through which a tide can pass. In order to enhance the uplifting effect, a face material may be provided on the outer periphery of the frame 5 so as to close the storage frame 6.

  In this reference example, for example, the height of the frame 5 is 1.5 times or more the width W of the lower portion of the frame 5.

A plurality of frame members 7 serving as projecting portions are provided at the bottom of the frame body 5, and the frame material 7 is made of a steel material or the like and is provided so as to project from the periphery of the frame body 5. 7 are connected by a frame member 8, and a plurality of frame portions 9 are formed by the frame members 7 and 8 and the cross beam member 3 at the bottom of the frame body 5. In this example, a frame portion 9 is provided on the entire circumference of the bottom portion of the frame body 5, and the frame material 8 has a peripheral shape substantially similar to the bottom shape of the frame body 5.

  Further, a plurality of reinforcing diagonal members 12 are obliquely provided between the front end side of the frame portion 9 and the frame body 5, and the reinforcing diagonal members 12 are arranged at substantially equal intervals around the frame body 5. It is provided corresponding to.

  Next, the effect | action is demonstrated about the said structure. The artificial reef 1 is lifted on a crane boom of a hoist ship, and the artificial reef 1 is sunk on the sea floor at the installation site. Thus, when the artificial reef 1 is installed on the sea bottom 21 of the sand, since the frame members 7 and 8 are projected to the outside, the ground can be stably grounded.

  Here, the artificial reef 1 vibrates due to the influence of external force or wave force. For example, as shown in FIG. 1, when the artificial fish reef 1 receives a tidal current in the direction of arrow Y, an ascending force F is generated with one side 5A of the frame 5 as an axis and the other side floating upward. Since 7 and 8 are overhanging, it is possible to face the ascending force F.

  As described above, in this reference example, in the artificial fish reef provided on the sea bottom 21 of the sand, the frame body 5 which is the fish reef body having the vertical and horizontal beam members 3 and 4 and the storage frame portion 6 which is the collecting space inside, and the frame Since it is provided with frame members 7 and 8 that are provided at the bottom of the body 5 and project to the outside of the frame 5, the artificial fish reef placed on the sea floor vibrates due to the influence of large waves and fast tides, The body 5 receives a rising force F with the one side 5A as an axis and the other side floating upward. On the other hand, when the bottom portion is widened by the frame members 7 and 8 which are the overhang portions, the turning radius becomes large, and the safety of the reef toppling is increased.

  Further, in this reference example, since the reinforcing diagonal member 12 is provided between the frame members 7 and 8 that are the overhanging portions and the frame member 5 that is the fish reef body, the strength of the frame members 7 and 8 is increased by the reinforcing diagonal member 12. Increases and stabilizes.

In this way, in this reference example, the frame body 5 serving as the fish reef body has a height that is 1.5 times or more the width W of the bottom portion. The stabilization can be achieved.
[ Reference Example 2 ]

5 and 6 show a reference example 2 of the present invention. The same reference numerals are given to the same parts as those of the reference example 1, and detailed description thereof will be omitted. A face material 11 is provided in the frame portion 9, and the face material 11 is provided so as to protrude outward from the periphery of the frame body 5, and the lower surface is formed to be substantially horizontal and flat. The face material 11 is made of a steel plate or a concrete plate, and the concrete plate is made of reinforced or unreinforced concrete. Note that the face material 11 may be provided in the bottom of the frame body 5, but is not provided in consideration of the time of setting. Further, a plurality of reinforcing diagonal members 12 are provided between the upper surface of the face member 11 and the frame body 5, and as shown in FIG. 3, the reinforcing diagonal members 12 are arranged at substantially equal intervals around the frame body 5. The vertical beam member 4 is provided corresponding to the position. Note that only the face material 11 may be provided without providing the frame portion 9.

  Next, the effect | action is demonstrated about the said structure. The artificial reef 1 is lifted on a crane boom of a hoist ship, and the artificial reef 1 is sunk on the sea floor at the installation site. In this case, since there is no face material 11 in the bottom, the artificial reef 1 can be smoothly submerged. When the artificial fish reef 1 is installed on the sandy sea bottom surface 21 in this way, the face material 11 projects outwardly, so that the ground can be stably grounded.

  Here, the artificial reef 1 vibrates due to the influence of the tidal current. For example, as shown in FIG. 1, when the artificial fish reef 1 receives a tidal current in the direction of the arrow Y, a rising force F is generated with the one side 5A of the frame 5 as an axis and the other side floating upward. Since 11 protrudes, it can oppose the said raising force F. FIG. In addition, since water pressure is applied to the upper surface of the face material 11 at the sea bottom, the face material 11 is pressed against the sea bottom surface 21, and the space between the face material 11 and the sea bottom surface 21 is in a reduced pressure state, and the upward force F Can be effectively suppressed.

  Moreover, when the artificial fish reef 1 is installed on the sea bottom surface 21 of sand, the sand on the sea bottom surface 21 below the face material 11 is sucked out by a tide or the like, and as shown in FIG. Accordingly, the face material 11 becomes lower than the surrounding sea bottom surface 21, thereby preventing the artificial reef from sliding. For example, when the sand 22 is dug, the face material 11 becomes lower than the surroundings by, for example, about 40 to 50 cm. In addition, since the artificial reef 1 is a heavy object made of steel or the like, an amount of sinking due to its own weight is included. Moreover, the sand below the face material 11 is dug, and at the same time, sand 22 is deposited on the face material 11 to form a weight, and the stability of the artificial reef 1 is improved.

As described above, in this reference example, in the artificial fish reef 1 provided on the sea bottom 21 of the sand, the frame 5 having the vertical and horizontal beam members 3 and 4 and the storage frame portion 6 serving as a collecting space inside, and the frame 5 Since the artificial fish reef placed on the sea floor vibrates due to the influence of large waves and fast tides, one side of the frame 5 is provided. With 5A as an axis, it receives a rising force F that lifts the other side upward. On the other hand, since the bottom portion is spread by the surface material 11 which is the overhanging portion, the surface material 11 comes into close contact with the sand and mud of the sea bottom surface 21 and when the surface material 11 is about to rise, the surface material 11 and the sea bottom surface 21 The pressure between the reefs is increased, and the seabed around the reefs is repeatedly scoured and buried, and sand mud accumulates on the face material 11 as a load, preventing the reefs from falling over. Has the effect of stabilizing.

  Further, since the sea bottom 21 is sandy, when the artificial reef 1 is installed on the sea bottom 21, sand 22 on the sea bottom 21 below the face 11 is sucked out by the tide or the like, and the 11 faces are in a mortar shape. The face material 11 becomes lower than the surrounding sea bottom surface 21, and the artificial reef 1 is prevented from sliding.

  As an effect on the embodiment, since the area of the face material 11 is equal to or larger than the area of the bottom surface of the frame body 5, the stability is excellent.

Figure 7 shows a first embodiment of the present invention, the same reference numerals to the same parts as the above Reference Examples 1 and 2, the detail is omitted the detailed description, the same parts as the above Reference Examples 1 and 2 The same reference numerals are given, and detailed description thereof will be omitted. In this example, an inner peripheral wall portion 13 and an outer peripheral wall portion 14 are provided on the inner periphery and outer periphery of the face member 11, and the face members 11, A box-shaped portion 15 is formed by the peripheral wall portion 13 and the outer peripheral wall portion 14.

  As described above, the present embodiment includes the box-shaped portion 15 having the face material 11 provided around the bottom portion, and the inner peripheral wall portion 13 and the outer peripheral wall portion 14 which are wall portions provided on the face material 11. The sand mud scoured in the box-like portion 15 accumulates, and there is an effect of further improving the fall stability of the fish reef. Furthermore, the periphery of the fish reef body is repeatedly scoured and buried by waves and tidal currents, so that the periphery of the fish reef becomes a mortar shape and the sliding of the fish reef is suppressed.

  In addition, as an effect on the embodiment, the overhanging portion includes a face member 11 surrounding the periphery of the bottom portion, and inner and outer peripheral wall portions 13 and 14 provided on the inner periphery and outer periphery of the face member 11, The entire periphery of the frame 5 can be surrounded by the box-shaped portion 15.

  The present invention is not limited to this embodiment, and various modifications can be made within the scope of the gist of the present invention. For example, the basic structure such as the material, shape, outer dimensions, etc. of the fish reef body may be selected as appropriate. Further, a storage basket or the like may be arranged in the collection space. Furthermore, unevenness for preventing slipping may be formed on the lower surface of the face material.

1 Artificial fish reef 3 Cross beam material 4 Vertical beam material 5 Frame (fish reef body)
5A Side 6 Storage frame (collection space)
11 Face material 12 Reinforced diagonal material
15 Box-shaped part F Lifting force

Claims (1)

In the artificial reef provided on the sandy sea bottom, it has a vertical and horizontal beam material and a reef body having a collecting space inside, and a projecting part provided at the bottom of the reef body and projecting outside the reef body. A reinforcing diagonal member is provided between the overhang portion and the fish reef body, and the fish reef body has a height of 1.5 times or more the width of the bottom part,
The overhanging portion includes a box-shaped portion having a face member provided around the bottom and a wall portion provided on the face member .

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