JP2578362B2 - Breakwater submerged embankment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a breakwater submerged dike having a seawater purification function.

<Conventional Technology> As a conventional wave-dissipating structure, there is a breakwater that is constructed by stacking concrete blocks and has both a certain degree of wave-dissipating effect and a beach nourishment effect.

<Problems to be solved by the present invention> The following problems exist in the above-described conventional wave-breaking technology using a breakwater.

(A) When the water depth of the breakwater increases, the volume of materials such as concrete blocks increases, which is uneconomical.

(Ii) The scour levee is likely to collapse due to scouring and waves at the front of the quay.

(C) The upper part of the breakwater protrudes above the sea surface to enhance the wave breaking effect.

 Therefore, there is a risk that the landscape will be spoiled.

<Object of the present invention> The present invention has been made in order to solve the above-mentioned problems, and it is possible to obtain a sufficient wave-dissipating effect, create a calm sea area, and prevent coastal erosion. The purpose of the present invention is to provide a submergence submergence with a seawater purification function.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

<A> Overall Structure The breakwater submerge 1 of the present invention comprises a top plate 11 and a bottom plate 13 made of concrete or the like, a side plate 14 having an opening 15,
It is a hollow box formed by a side plate 16 connecting the parts 14, and the box is filled with a filling material 2.

<B> Top plate The top plate 11 is a plate body attached to the upper surface of the submerged bank 1 at an angle.

The inclination angle and the length in the inclination direction of the top plate 11 are selected at any time according to the installation position of the submerged bank 1 and a desired wave-elimination effect.

Further, a projection 12 for promoting wave breaking may be provided on the upper surface of the top plate 11 in a direction perpendicular to the inclination direction of the top plate 11.

The position and the number of the protrusions 12 are selected at any time according to a desired wave-elimination effect.

<C> Side plate The side plate is a plate that connects between the top plate 11 and the bottom plate 13, and is a side plate.
It is composed of 14 and a side plate 16.

The drawing board 14 is attached in the inclination direction of the top board 11, and
Forming two opposing sides, a plurality of openings 15
Has been established.

The size and number of the openings 15 are not so large as to reduce the strength of the side plate 14 and are set to such an extent that an intruding wave can pass through the submerged levee 1.

Therefore, the seawater flowing from the opening 15 of the one side plate 14 is
It is possible to flow out of the opening 15 of the other side plate 14.

The side plate 16 is attached in parallel with the inclination direction of the top plate 11,
It is a plate that closes two opposing side surfaces adjacent to the side plate 14.

<D> Filling material The filling material 2 is a lump of a stone or the like packed in the submerged bank 1 configured as described above.

The type and particle size of the filling material 2 are such that the invading waves can pass through the submerged levee 1, and algae, shellfish, crustaceans, microorganisms, etc. can appropriately propagate in the gap portion in the filling state. Shall be.

<E> Installation method First, level the sea floor where submerge 1 will be installed.

Next, as shown in FIG. 2, the submerged bank 1 is installed so that the side plate 14 attached to the lowermost side of the top plate 11 is orthogonal to the incident direction of the incident wave A.

Then, on the offshore side and the shore side of the submerged levee 1, rough rubble 3 and the like that can permeate seawater are piled up and the submerged levee 1 is fixed.

At this time, the offshore rubble 3 should be constructed low because the opening 15 of the side plate 14 needs to be sufficiently exposed, and the shore side should be constructed to the same height as the side plate 14.

<Operation> Next, the operation of the present invention will be described.

<A> Reduction of reflected wave Since the entire structure of the submerged bank 1 of the present invention is submerged below the water surface, a part of the incident wave A transmits through the upper surface of the top plate 11 (arrow C).

Moreover, since the side plate 14 is a permeable wall, seawater can be transmitted from inside the submerged bank 1 (arrow D).

Therefore, a partial image of the incident wave A is dispersed into the transmitted waves C and D, and energy is dissipated in this process, so that the energy of the opposite wave B reflected offshore is reduced.

The present invention relates to a transmitted wave C passing through the top plate 11 of the submerged bank 1.
Then, the transmitted wave D transmitted through the rubble 3 and the side plate 14 can be dissipated as follows.

<B> Wave-dissipating action of transmitted wave by the top plate The energy of the transmitted wave C transmitted to the shore side over the top surface of the top plate 11 is because the top plate 11 is inclined upward toward the shore side. The energy of the transmitted wave C is gradually concentrated.

Therefore, the transmitted wave C whose energy is concentrated is
The stable shape cannot be maintained, and the waves are forcibly broken.

Therefore, the transmitted wave C can be attenuated by the top plate 11.

Further, by providing the projections 12 on the top surface of the top plate 11 to increase the surface roughness, the wave canceling action of the transmitted wave C can be further enhanced.

<C> Wave-dissipating action of transmitted wave by side plate and filling material The energy of the transmitted wave D transmitted to the shore side through the opening 15 of the offshore and shore side plate 14 and the gap between the filling material 2 is The energy is attenuated by frictional resistance when seawater flows through the gap of the filling material 2 and by turbulence of the water flow in the gap.

Therefore, the transmitted wave C can be attenuated by the side plate 14 and the filling material.

<D> Purification action When seawater passes through the gap between the filling materials 2, organic substances in the seawater are oxidized and decomposed by algae, shellfish, crustaceans, microorganisms, etc. attached to the filling material 2, so that the seawater is purified. Is done.

Furthermore, the amount of dissolved oxygen in the seawater increases due to the aeration effect of the forced breaking wave on the submerged bank 1, and the purification of the seawater is further promoted.

<Effects of the Present Invention> Since the present invention has been described above, the following effects can be expected.

<A> Conventional offshore breakwaters are easily collapsed by scouring or waves at the front of the offshore breakwater.

On the other hand, the present invention is a submerged structure in which the entire structure is submerged below the water surface, so that a part of the incident wave passes through the upper surface of the top plate.

Moreover, since the side plate is a transparent wall, it can be transmitted from inside the submerged embankment.

Therefore, the incident wave is dispersed into the two transmitted waves, and the energy of the reflected wave reflected offshore is reduced by the amount of energy dissipated.

Therefore, it is possible to prevent scouring at the front of the submerged embankment and collapse due to waves.

<B> Conventional offshore breakwaters are uneconomical due to the large volume of material such as concrete blocks when the water depth increases.

However, since the submerged embankment of the present invention is formed by a hollow box, the volume of a material such as concrete can be small, and it is economical.

<C> The seawall purifies seawater by oxidatively decomposing organic substances in seawater by algal shells, crustaceans, microorganisms, etc. attached to the filling when seawater passes through the gap between the fillings. can do.

Further, the amount of dissolved oxygen in seawater can be increased by the aeration effect of forced breaking waves on the submerged levee, and the purification of seawater can be further promoted.

<D> As described above, the submerged embankment of the present invention can reduce the energy of the reflected wave reflected offshore and can dissipate the transmitted wave transmitted through the top plate and the side plate.

That is, the energy of the transmitted wave transmitted to the shore side over the upper surface of the top plate is gradually concentrated because the top plate is inclined upward toward the shore side.

Therefore, the transmitted wave with the concentrated energy cannot maintain a stable shape, and is forcibly broken and attenuated.

In addition, the energy of the transmitted wave transmitted through the gap between the offshore and shore side plates and the gap between the filling materials and transmitted to the shore side depends on the frictional resistance when seawater flows through the gap between the filling materials, and Energy is attenuated by turbulence in ocean currents in the gap.

As described above, the submerged embankment of the present invention returns to the offshore side as a reflected wave while dissipating a part of the energy of the incident wave, and effectively transmits the remaining transmitted wave by the top plate, the side plate, and the filling material. Can dissipate and break waves.

 Therefore, the wave canceling effect can be significantly improved.

<E> In the submerged embankment of the present invention, the incident wave is dispersed into the reflected wave and the transmitted wave, and the energy of the reflected wave reflected offshore is reduced by the amount of energy dissipated.

Therefore, the reflected wave does not cause the overlapping wave, so that there is no adverse effect on a ship or the like navigating in the vicinity.

<F> The upper part of the conventional breakwater protrudes above the sea surface in order to enhance the wave-dissipating effect, and may damage the landscape.

However, since the present invention is a submerged structure in which the entire structure is submerged below the water surface, there is no possibility of damaging the landscape.

<G> By providing projections on the top surface of the top plate to increase the surface roughness, the wave-eliminating action of transmitted waves can be further enhanced.

<H> Since the entire structure of the latent image of the present invention is integrated, the latent image has excellent stability against wave force and does not have a risk of being broken like a conventional breakwater.

<R> Some conventional submersible structures have a structure in which only one of the side plates is open (Japanese Patent Application Laid-Open No. 64-14411).

In this case, since the seawater does not pass through the submerged embankment, the wave-dissipating effect due to the permeation cannot be obtained.

On the other hand, the submerged embankment of the present invention has a structure in which openings are provided in side plates at both ends in the inclination direction of the top plate.

Therefore, the seawater can be transmitted from one side plate to the other side plate through the submerged levee to obtain a wave-dissipating effect.

[Brief description of the drawings]

 FIG. 1: Illustration of an embodiment of the present invention FIG. 2: Illustration of operation of the present invention

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Fumio Koyama 1-25-1, Nishishinjuku, Shinjuku-ku, Tokyo Taisei Corporation (56) References JP-A 64-14411 (JP, A)

Claims (2)

(57) [Claims] 1. A submerged embankment for sinking waves by sinking the entire structure below the surface of the water, comprising: a hollow box formed by a top plate, a bottom plate, and a side plate, the top plate having a predetermined inclination angle; A wave-dissipating submergence dyke comprising a transmission side plate having an opening attached in the inclination direction of the top plate, a closed side plate attached in parallel to the inclination direction of the top plate, and a filling material packed in the box. 2. The wave breaking submerged dam according to claim 1, wherein a projection is provided on an upper surface of the top plate.