JP2852564B2 - Wave breaking facility - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wave breaking facility,
The present invention relates to a wave breaking facility that breaks a wave at a predetermined position using deformation caused by a change in water depth.

[0002]

2. Description of the Related Art Conventionally, a wave refraction phenomenon, that is, a phenomenon in which the wave speed decreases at a shallow depth of water and a phase delay of the wave occurs to change the wave direction, is used to concentrate the wave to reduce the wave energy. Wave control structures for effective use are known. Examples of such a wave control structure include a submerged horizontal plate in which a flat lens-shaped flat plate is installed in the sea, and Japanese Patent Application No. 2-20 filed by the present applicant.
No. 8137 describes a wave control structure in which a substantially columnar member or a substantially cylindrical member is arranged in a lens shape as a whole. In addition, by providing a wave power utilization facility, for example, a wave power generation device or the like in a sea area where waves are concentrated by these wave control structures, the wave energy is absorbed and used, and the waves are eliminated to form a calm sea area. Things are known.

[0003]

However, in such a conventional wave control structure, no equipment for breaking the wave is provided, and only the natural breaking of the wave due to the shallow sea deformation can be expected. Therefore, even if the wave breaking sea area is not constant and the wave concentrates near the focal point and the wave height increases, there is no means to actively break the wave at that position,
There is a problem that it is not possible to obtain high breaking waves at Minetaka suitable for surfing and other leisure activities.

The present invention has been made in order to solve the above-mentioned problem, and an object of the present invention is to provide a high breaking wave suitable for leisure such as surfing in a fixed sea area near a focal point of a lens type wave control structure. To provide a wave breaking facility that can easily obtain the wave breaking facilities.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned object, and the gist of the present invention is that a planar shape provided at a predetermined water depth based on a correlation with a wavelength of a wave has a lens type submerged structure. objects and, Ri Do a combination of a subsea projections provided on the waters near the focal point of the lens, the died water structure, a plurality of
Place the cylindrical member so that its axis is substantially perpendicular to the wave direction.
Arranged at regular intervals, and a plate
Some in the name Ru breaking facility constructed without arrangement.

Here, the predetermined water depth based on the correlation with the wave wavelength is a water depth at which the wave is affected by the sea bottom, calculated from the wave wavelength, and more specifically, a water depth less than 1/2 of the wave wavelength. Say the water depth.

A submerged structure of a lens type is, for example, a flat plate having a planar shape such as a convex lens type having a focal point or a Fresnel lens type, or a plurality of unit bodies are assembled so as to have these shapes. It was submerged underwater across the direction.

[0008] Further, the underwater projection provided in the sea area near the focal point of the lens is an artificial projecting projecting from the sea bottom at and / or around the focal point of the lens-shaped submerged structure and arranged in a direction crossing the wave direction. Natural structures and natural reefs whose upper end is located at a predetermined water depth, for example, 0.5 to 3.0 times the wave height of the increased wave passing therethrough,
It has various shapes such as a mound shape, a flat plate shape, a rectangular parallelepiped shape, and a rod shape. Also, the length in the direction perpendicular to the wave direction is
It is suitably designed according to the purpose of using the breaking wave, and for example, when used for surfing, it is preferably 20 to 30 m. Then, these underwater projections are constructed in accordance with the focal position of the submerged structure. In the case of a natural reef or the like, in order to position them near the focal point, the above-mentioned submerged structures are referred to based on these positions. A submerged structure may be installed.

[0009]

According to the present invention, a wave traversing a lens-shaped submerged structure is refracted with a phase delay of the wave. The refracted wave concentrates toward the focal point of the lens and increases its wave height. The wave having a higher wave height further increases its wave height due to shallow water deformation caused by a submerged projection located near the focal point of the lens, and breaks beyond the breaking limit wave height.

[0010]

Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIGS. 1 and 2, the wave breaking facility of the present invention comprises a convex lens type submerged structure 10 and a focal point 1 thereof.
3 and a mound-like structure 20 as a submarine projection installed on the seabed at a position.

The submerged structure 10 includes a large number of cylindrical members 11.
Is assembled so that its axis is substantially perpendicular to the wave direction X, and the overall planar shape is a convex lens type.
By the support 12 assembled by connecting the rod-shaped members, it is fixed at a water depth of less than half the wavelength of the wave traversing it. Then, the waves traversing the submerged structure 10 cause a phase delay of the waves due to a change in water depth, are refracted inward, and are concentrated while increasing the wave height toward the focal point 13 of the submerged structure 10 as a convex lens. . As a result, the wave height of the wave crossing the submerged structure 10 becomes 2 to 5 times near the focal point 13.

The submerged structure 10 to which the columnar member 11 is attached is characterized in that, when compared with a submerged structure formed of a flat plate or the like, the reflected wave is reduced when the wave crosses, and the energy loss is reduced. And the wave collection efficiency can be increased. Further, the submerged structure 10 to which the columnar member 11 is attached may be moored at a predetermined water depth without being fixed by an anchor member and a chain.

The mound-like structure 20 is constructed by stacking rubble from the seabed in a region surrounding the focal point 13 and has an upper end having a height of 0.5% of an increased wave passing therethrough.
It is located at a depth of up to 3.0 times and the length in the direction perpendicular to the wave direction is 20 to 30 m. And the submerged structure 10
The waves converging with increasing wave height towards the focal point 13 of
The wave height is further increased by the shallow water deformation by the mound-like structure 20, and the wave breaks beyond the wave breaking limit wave height.

In this manner, the breaking waves actively obtained in a certain place, that is, in the vicinity of the focal point 13 of the submerged structure 10, have a large peak and are effectively used for leisure such as surfing.

FIGS. 3 to 5 show other embodiments of the underwater projection.

The underwater projection shown in FIG. 3 is one in which a flat plate 21 is fixed to the upper end of a support pile 22 that is driven into the sea floor, and can be manufactured easily and at low cost.

The underwater projection shown in FIG.
Is attached to the upper end of a jack 25 erected from a concrete foundation 24 constructed on the sea floor.
The shape of the wave can be controlled by expanding and contracting the jack 25 according to the height of the wave and changing the water depth at which the upper end of the mound member 23 is located. The submerged structure 1
Even if the height of the wave crossing zero is low, the breaking of the wave can be surely caused by making the water depth at the upper end of the mound member 23 shallow.

The underwater projection shown in FIG. 5 is one in which the caisson 26 constructed on the ground is towed and sunk on the seabed, and can be easily installed even in a deep sea area.

In this embodiment, the case where the underwater projections are provided in accordance with the focal position of the submerged structure 10 has been described. However, in the case where a natural reef or the like is used, these shall be located at the focal position. The position of the submerged structure 10 may be selected based on these, and the submerged structure 10 may be constructed.

[0021]

As described above, the wave breaking facility of the present invention comprises a lens-shaped submerged structure and a submerged projection provided in the sea area near the focal point of the lens-shaped submerged structure. The wave whose wave height has increased while concentrating afterwards is forcibly broken near the focal point by the action of a submerged projection. Therefore, by obtaining a high breaking wave at a high place in a certain place, it can be effectively used for leisure such as surfing. Further, the energy of the waves is dissipated by the breaking waves, so that calming of the nearby sea area can be achieved.

By changing the height of the underwater projection and changing the water depth at the upper end thereof, it is possible to control the shape of the breaking wave and to form an optimal wave according to the purpose. Furthermore, a wave having a small wave height can be broken to obtain a calm sea area.

[Brief description of the drawings]

FIG. 1 is a plan view showing a wave breaking facility of the present invention.

FIG. 2 is a sectional view showing a wave breaking facility of the present invention.

FIG. 3 is a cross-sectional view showing an example of a submerged projection constituting the wave breaking facility of the present invention.

FIG. 4 is a cross-sectional view illustrating an example of a submerged protrusion constituting the wave breaking facility of the present invention.

FIG. 5 is a cross-sectional view showing an example of a submerged projection constituting the wave breaking facility of the present invention.

[Explanation of symbols]

 10 Submerged structure 13 Focus 20 Mound-like structure 20 (underwater projection)

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-64-48916 (JP, A) JP-A-62-148705 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) E02B 3/06

Claims (1)

(57) [Claims] 1. A submerged structure of a lens type having a planar shape provided at a predetermined water depth based on a correlation with a wavelength of a wave, and a submarine projection provided in a sea area near a focal point of the lens.
The submerged structure has a plurality of cylindrical members whose axes are
At predetermined intervals so as to be substantially perpendicular to the
Configuration without placing a plate between each cylindrical member
And ing by breaking facility.