JP3609052B2

JP3609052B2 - Wave-dissipating method and device

Info

Publication number: JP3609052B2
Application number: JP2001383566A
Authority: JP
Inventors: 銀二郎恩田
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-12-17
Filing date: 2001-12-17
Publication date: 2005-01-12
Anticipated expiration: 2021-12-17
Also published as: JP2003184047A

Description

【０００１】
【発明の属する技術分野】
本発明は消波方法及び消波装置、より詳細には、海や河川の水中に設置されて消波機能を発揮し、以て津波や高波等による被害を未然に防止するための消波方法及び消波装置に関するものである。
【０００２】
【従来の技術】
津波や高波等による被害を防止するために、海岸を工事して設置される所謂岸壁や防波堤の他に、沿岸部の比較的浅瀬に設置される消波装置が種々考えられている。水面より露出するくの字状の堤体を、同一方向に向けて複数並設し、各堤体間にくの字状の水路を設けたもの（特開平６−２１２６１１号公報）や、全方位の波向きに対して弧状に（略半球状に）形成されると共に、内部に中空室が設けられ、この中空室を、主たる波向きに対向する部位に設けた開口部を介して海中と連通させたもの（特開平１０−２３７８４２号公報）等がその例である。
【０００３】
【発明が解決しようとする課題】
上記従来の消波装置は、その構造上それ自体高価となるだけでなく、設置にも手間がかかり、トータルコストが嵩む欠点がある。
そこで本発明は、単純な構造で、装置自体のコスト及び設置コストが比較的低廉で、しかも有効な消波効果を有する消波方法及び消波装置を提供することを課題とする。
【０００４】
【課題を解決するための手段】
上記課題を解決するための本発明に係る消波方法は、水圧が高くなる波の山部における水を、前記山部よりも水圧が低い波の谷部に、圧力差を利用して導くことことを特徴とし、また、長さ方向に伸びる開口側面を有する消波体を設け、前記消波体を、波の進行方向に対し傾け且つ前記開口側面を波に向けて設置し、波が前記消波体に当った際に前記消波体内に生ずる水圧差により、前記消波体内に流れを生じさせるようにしたことを特徴とする。
【０００５】
上記課題を解決するための本発明に係る消波装置は、長さ方向に伸びる開口側面を有する消波体を１又は複数、前記開口側面を波に向け且つ波の進行方向に対して傾けて設置して成り、好ましくは、前記消波体に、中空の固定杭を設置し、前記中空固定杭に外部から高圧水を供給可能にする。
【０００６】
【発明の実施の形態】
本発明の実施の形態を添付図面に依拠して説明する。本発明に係る消波方法は、水圧が高くなる波の山部における水を、前記山部よりも水圧が低い波の谷部に、圧力差を利用して導くことを特徴とし、より詳細には、長さ方向に伸びる開口側面を有する消波体を設け、前記消波体を、波の進行方向に対し傾け且つ前記開口側面を波に向けて設置し、前記波の山部が前記消波体の、波の進行方向手前側端部に位置するときに、前記消波体の反対側端部との水圧差により、前記消波体の手前側端部から前記消波体の反対側端部への流れが生ずるようにしたことを特徴とする。
【０００７】
図１は、上記発明に係る方法を実施するための本発明に係る消波装置の構成図で、図中１は、長さ方向に伸びる開口側面２を有する、換言すれば、断面がＣ字状ないし半円形の筒状消波体で、固定杭３を有し、この固定杭３を介して海底に固定される。消波体１は、設置場所において想定される高波や津波の規模に応じたサイズとされ、例えば、長さが３〜１５ｍ、直径が２〜５ｍ程度とされる。
【０００８】
消波体１は、沿岸部に通例複数、波に向けて開口側面２を配し、且つ、波の進行方向に対して、例えば４５度傾けた状態に設置される（図３参照）。
【０００９】
図２に示す例は、固定杭３を中空として先端に噴射ノズル３ａを設け、この中空固定杭３にホース４を接続することにより、外部からの高圧水を供給可能にしたものである。この構成は、本装置の、高さ調整を含めた海底への設置作業を容易且つ迅速に行わせるためのもので、設置作業に際しては、消波体１の外側面に設けたロープ掛け５にロープ６を掛けてクレーンで吊るし、海底に降ろす際に中空固定杭３内に高圧水を供給する。
【００１０】
高圧水は、中空固定杭３の噴射ノズル３ａから海底に向けて噴射され、中空固定杭３の先端部分の砂を吹き上げる。これにより、中空固定杭３の挿入孔が形成されるので、そのまま消波体１を降ろしていけば、中空固定杭３がその孔内に容易且つスムーズに進入していく。中空固定杭３が埋入したところでロープ６をフックから外すが、その後中空固定杭３の回りの砂が締まり、中空固定杭３は確固と固定される。
【００１１】
また、消波体１の設置場所を移動させる場合や消波体１の海底からの高さ調整をするような場合にも、同様に中空固定杭３に高圧水を供給すれば、周囲の砂が吹き崩されるので、引き抜きが容易となる。
【００１２】
このようにして設置した消波装置に対し、波が到来すると、波は先ず、波の進行方向に対して傾斜状態に設置されている消波体１の沖側端部に当たり、消波体１の全体をみると、その部分の水圧が最も高くなる。従って、消波体１の沖側端部内と陸側端部内において水圧に大きな差が生じ、その結果、消波体１内において、水圧の高い沖側から水圧の低い陸側への流れが生じ、これにより波の山が崩れ、より低い波高となって、消波体１を越えていく。
【００１３】
この現象が、波の進行に伴なって消波体１の全長に亘って起こる。その場合、波の山が消波体１の中間部辺りに到ると、消波体１内の水流は前後両方向に生ずるようになる。かくして、波が消波体１を越える際に波高の低減現象が次々と起こり、全体的に有効な消波が行われる。
【００１４】
【発明の効果】
本発明は上述した通りであって、波が本装置を通過する際に、波の山と谷間における水圧の差を利用して消波体内に水流を生じさせることにより、波高を低く抑えることができ、以て津波、高波等の被害の発生を有効に防止し得るものであり、しかも、構成が簡易で設置が容易なため、廉価にて供給設置し得る効果がある。
【００１５】
請求項４に記載の発明においては、高圧水を利用して杭の打込み作業を行うことができるので、より設置が容易となり、設置場所移動や高さ調整に際しての杭抜き作業も容易となる効果がある。
【図面の簡単な説明】
【図１】本発明に係る消波装置の一実施例の斜視図である。
【図２】本発明に係る消波装置の他の実施例の斜視図である。
【図３】本発明に係る消波装置の使用状態図である。
【符号の説明】
１消波体
２開口側面
３固定杭
３ａ噴射ノズル
４ホース
５ロープ掛け
６ロープ[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a wave-dissipating method and a wave-dissipating device, and more particularly, a wave-dissipating method for preventing damage caused by a tsunami, a high wave, and the like by being installed in the water of a sea or a river. And a wave-dissipating device.
[0002]
[Prior art]
In order to prevent damage caused by tsunamis, high waves, and the like, various wave-dissipating devices installed in relatively shallow waters in coastal areas have been considered in addition to so-called quay walls and breakwaters constructed by constructing the coast. A plurality of U-shaped dam bodies exposed from the water surface are arranged in parallel in the same direction, and a U-shaped water channel is provided between each dam body (JP-A-6-212611), or all It is formed in an arc shape (substantially hemispherical) with respect to the direction of the azimuth wave, and a hollow chamber is provided inside, and this hollow chamber is connected to the sea through an opening provided in a portion facing the main wave direction. An example is a communication system (Japanese Patent Laid-Open No. 10-237842).
[0003]
[Problems to be solved by the invention]
The conventional wave-dissipating device is not only expensive per se due to its structure, but also has a drawback that it takes time to install and increases the total cost.
Therefore, an object of the present invention is to provide a wave-dissipating method and a wave-dissipating apparatus that have a simple structure, the cost of the apparatus itself and the installation cost are relatively low, and that have an effective silencing effect.
[0004]
[Means for Solving the Problems]
The wave-dissipating method according to the present invention for solving the above-described problems guides water in a peak portion of a wave having a high water pressure to a trough portion of a wave having a lower water pressure than the peak portion using a pressure difference. A wave-dissipating body having an opening side surface extending in a length direction, the wave-dissipating body being inclined with respect to a traveling direction of the wave and the opening side surface facing the wave, A flow is generated in the wave-dissipating body due to a difference in water pressure generated in the wave-dissipating body when it hits the wave-dissipating body.
[0005]
A wave-dissipating device according to the present invention for solving the above-mentioned problems is characterized in that one or a plurality of wave-dissipating bodies having an opening side surface extending in the length direction, the opening side surface facing the wave, and inclined with respect to the wave traveling direction. Preferably, a hollow fixed pile is installed in the wave-dissipating body, and high-pressure water can be supplied to the hollow fixed pile from the outside.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the accompanying drawings. The wave-dissipating method according to the present invention is characterized in that the water in the peak portion of the wave where the water pressure becomes high is guided to the trough portion of the wave whose water pressure is lower than that of the peak portion using a pressure difference. Is provided with a wave-dissipating body having an opening side surface extending in the length direction, the wave-dissipating body is inclined with respect to the wave traveling direction and the opening side surface is directed toward the wave, and the peak portion of the wave is When the wave body is positioned at the front side end portion of the wave traveling direction, the water pressure difference between the wave body and the opposite side end portion causes the wave body from the front side end portion to the opposite side of the wave quenching body. It is characterized in that a flow to the end portion occurs.
[0007]
FIG. 1 is a configuration diagram of a wave-absorbing device according to the present invention for carrying out the method according to the present invention, in which 1 has an opening side surface 2 extending in the length direction, in other words, a C-shaped section. This is a cylindrical or semicircular wave breaker having a fixed pile 3 and is fixed to the seabed via the fixed pile 3. The wave-dissipating body 1 is sized according to the magnitude of high waves and tsunamis assumed at the installation location, and has a length of about 3 to 15 m and a diameter of about 2 to 5 m, for example.
[0008]
The wave-dissipating body 1 is usually installed in a state where a plurality of opening side surfaces 2 are arranged toward the wave and inclined by 45 degrees with respect to the traveling direction of the wave, for example, on the coast (see FIG. 3).
[0009]
In the example shown in FIG. 2, the fixed pile 3 is made hollow and an injection nozzle 3 a is provided at the tip, and a hose 4 is connected to the hollow fixed pile 3 so that high-pressure water from the outside can be supplied. This configuration is intended to facilitate and quickly perform the installation work on the seabed including the height adjustment of this apparatus. In the installation work, the rope hook 5 provided on the outer surface of the wave-dissipating body 1 is used. The rope 6 is hung with a crane, and high-pressure water is supplied into the hollow fixed pile 3 when it is lowered to the seabed.
[0010]
The high-pressure water is sprayed from the spray nozzle 3 a of the hollow fixed pile 3 toward the seabed, and blows up the sand at the tip of the hollow fixed pile 3. Thereby, since the insertion hole of the hollow fixed pile 3 is formed, if the wave-dissipating body 1 is lowered as it is, the hollow fixed pile 3 enters the hole easily and smoothly. When the hollow fixed pile 3 is embedded, the rope 6 is removed from the hook. Thereafter, the sand around the hollow fixed pile 3 is tightened, and the hollow fixed pile 3 is firmly fixed.
[0011]
Also, when moving the installation place of the wave-dissipating body 1 or adjusting the height of the wave-dissipating body 1 from the seabed, if high-pressure water is supplied to the hollow fixed pile 3 in the same manner, the surrounding sand Since it is blown away, it becomes easy to pull out.
[0012]
When a wave arrives at the wave-dissipating device thus installed, the wave first hits the offshore end of the wave-dissipating body 1 installed in an inclined state with respect to the traveling direction of the wave. As a whole, the water pressure in that part is the highest. Therefore, there is a large difference in water pressure between the offshore side end and the land side end of the wave-dissipating body 1, and as a result, a flow from the offshore side with high water pressure to the land side with low water pressure occurs within the wave-dissipating body 1. As a result, the mountain of waves breaks down, resulting in a lower wave height and exceeding the wave-dissipating body 1.
[0013]
This phenomenon occurs over the entire length of the wave-dissipating body 1 as the wave travels. In that case, when the wave peak reaches around the middle part of the wave-dissipating body 1, the water flow in the wave-dissipating body 1 is generated in both the front and rear directions. Thus, when the wave passes over the wave-dissipating body 1, the phenomenon of wave height reduction occurs one after another, and effective wave elimination is performed as a whole.
[0014]
【The invention's effect】
The present invention is as described above, and when the wave passes through the apparatus, the wave height can be kept low by generating a water flow in the wave-dissipating body using the difference in water pressure between the peak and valley of the wave. Therefore, the occurrence of damage such as tsunami and high waves can be effectively prevented, and the structure is simple and easy to install, so that it can be supplied and installed at low cost.
[0015]
In the invention described in claim 4, since the pile driving work can be performed using high-pressure water, the installation is facilitated, and the pile removal work at the time of installation place movement and height adjustment is also facilitated. There is.
[Brief description of the drawings]
FIG. 1 is a perspective view of an embodiment of a wave-dissipating device according to the present invention.
FIG. 2 is a perspective view of another embodiment of the wave-absorbing device according to the present invention.
FIG. 3 is a use state diagram of the wave-absorbing device according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Wave absorber 2 Open side 3 Fixed pile 3a Injection nozzle 4 Hose 5 Rope hook 6 Rope

Claims

A wave-dissipating body having a C-shaped cross section having an opening side surface extending in the length direction is installed in a relatively shallow water in a coastal area with the opening side surface facing the wave traveling direction and inclined with respect to the wave traveling direction, When a wave hits an offshore end of the wave-dissipating body, a flow is generated in the wave-dissipating body due to a water pressure difference generated between the offshore-side end and the land-side end of the wave-dissipating body. A wave-dissipating method characterized by reducing the wave height.

One or more wave-dissipating bodies having a C-shaped cross section having an opening side surface extending in the length direction, the opening side surface facing the wave traveling direction and inclined with respect to the wave traveling direction, and relatively shallow water in the coastal area When the wave hits the offshore end of the wave-dissipating body, a difference in water pressure generated between the offshore-side end and the land-side end of the wave-dissipating body causes the wave-dissipating body to A wave-dissipating device characterized in that it is possible to prevent a flow from occurring.

The wave-dissipating device according to claim 2, wherein a hollow fixed pile is installed on the wave-dissipating body, and high-pressure water can be supplied to the hollow fixed pile from the outside.