JPH07216861A - Sink-and-float type wave suppressor - Google Patents

Abstract

PURPOSE:To provide a sing-and-float type wave suppressor which can prevent a bag from being extremely bent, which can prevent the bag from being damaged even though sinking and floating are repeated several times, and which can be simplified more then a conventional one by connecting an air feeding and venting device only to the other end of the bag. CONSTITUTION:During an underwater construction, a wave suppressor is floated at the sea surface by the buoyancy of air filled a bag 100 so as to suppress the diffusion of floating mud and to facilitate a work. A forcibly sinking weight 140 is provided at one end of the bag 100 so that the suppressor is smoothly sunk underwater without being bent, by venting air from the bag 100 whenever it is necessary, A hose 300 is connected to the other end of the bag 100, and is connected to an air feeding and discharging device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wave canceller for canceling waves by floating on the water surface.
Specifically, it is used to prevent situations such as floating mud generated during underwater construction such as dredging and land reclamation from flowing out of the construction area due to the effects of waves and spreading to contaminate the fishing ground. The present invention relates to a floating sinking and sinking wave sink that can be submerged in water.

[0002]

2. Description of the Related Art During underwater construction such as dredging and landfill,
Suspended mud is generated. If this floating mud, etc. flows out and spreads out of the construction area due to the influence of the waves, it may pollute the fishing ground, so it is necessary to prevent such a situation. Further, particularly in the case of construction work under the sea, there is a problem that the construction period is prolonged and the construction cost is increased due to a decrease in work efficiency when affected by waves. For this reason,
Conventionally, in underwater construction, wave countermeasures have been taken to suppress the generation of waves in the construction area.

As a conventional countermeasure against waves, the following floating-sink type wave breaker is known (see JP-A-60-175615, page 5, FIG. 4). With reference to FIG. 5, according to the publication, the above-mentioned floating-sink type wave canceller is a first flexible tubular float 2A.
And a second flexible tubular float 5A positioned parallel to the first flexible tubular float 2A, and both the floats 2
A flexible plate-like body 3 integrally connected to A and 5A, a canvas 6 connected along the lower end of the first flexible tubular float 2A, and a canvas 6 attached along the lower end of the canvas 6. It also has a plurality of weights 9.

According to the floating and sinking type wave absorber having the above structure, the canvas 6
By doing so, it is possible to suppress the diffusion of suspended mud, etc., generated in the construction area. In addition, the wave traveling in the direction of arrow C in the figure is extinguished by the first flexible tubular float 2A and the second flexible tubular float 5A, and the generation of the wave in the work area can be suppressed.

[0005]

[Problems to be Solved by the Invention] By the way, in the sea or lake where the above-mentioned floating and sinking type wave breaker is installed near the sea, or in the sea or lake where importance is attached to the landscape, it is necessary to actually work. If not, the wave breaker is very annoying. Therefore, the floating-sink type wave breaker can be submerged in water except during the actual work. That is, referring to the figure, both the floats 2A,
The sinking floats 20 and 21 are connected in a T shape in the middle of 5A, and both the floats 2A and 5A are connected to an air supply / exhaust device on land through a conduit.

Referring to FIG. 6, if the floats 2A and 5A are exhausted at the required time, the floats 2A and 5A are drawn into the water in a V shape (upper left of page 3 of the same publication). See line 13 through bottom left, second line). However, if it sinks as shown in FIG. 6, the sink float 20,
21 and the connecting portion C between the two floats 2A and 5A may be extremely bent and damaged. Further, in order to surely sink the air in the floats 2A and 5A without generating air reservoirs, the air must be exhausted from both sides of the floats 2A and 5A, resulting in a large scale of the device. There is also.

SUMMARY OF THE INVENTION An object of the present invention is to provide a float-sink type wave breaker which can easily sink and float without damaging the wave breaker.

[0008]

According to a first aspect of the present invention, there is provided a floating and sinking type wave-dissipating body which has flexibility and which floats above water by being filled with air. A canvas attached along the longitudinal direction of the bag body and provided with a weight at the lower end, and hanging from the bag body into the water to suppress the flow of water in the water due to the influence of waves, and air against the bag body. An air supply / exhaust device that supplies or exhausts the air, and when the air in the bag body is exhausted by the air supply / exhaust device,
In a floating sinking and sinking wave canceling body including a bag and a weight for forcible sinking forcibly submerging the canvas, the weight for forcible sinking is provided at one end in the longitudinal direction of the bag, The air supply / exhaust device is connected to the other end of the bag body in the longitudinal direction.

The float-sink wave absorber according to a second aspect of the present invention is the float-sink wave absorber according to the first aspect, wherein the bags are arranged parallel to each other in the water surface direction while floating on the water. It is composed of a pair of connected tubular members, and the canvas is attached along the longitudinal direction of each of the pair of tubular members.

Further, the float-sink wave absorber according to claim 3 is
In the floating and sinking type wave canceller according to claim 2, the distance between the pair of tubular members is 5 m or more. The float-sink wave absorber according to claim 4 is the float-sink wave absorber according to any one of claims 1 to 3, characterized in that the length from the upper end to the lower end of the canvas is 4 m or more. Is.

[0011]

According to the float-sink wave absorber according to claim 1, when air is supplied into the bag body by the air supply / exhaust device connected to the other end of the bag body, the bag body becomes a so-called float and floats above the water. To surface. Since a canvas is attached to this bag along the longitudinal direction and a weight is provided on this canvas, if the bag floats, the canvas hangs from the bag into the water. To do. With this canvas, it is possible to prevent mud and the like generated in water during dredging work from being diffused due to the influence of waves and leaking from the construction area to the outside. Moreover, since the bag floating on the water cancels the wave on the water surface, the wave in the work area can be suppressed.

On the other hand, when the air in the bag is exhausted by the air supply / exhaust device, the bag is flexible and contracts, and the buoyancy is reduced. Further, since a weight for forced subsidence is provided at one end in the longitudinal direction of the bag body, the bag body with reduced buoyancy is submerged in water in order from one end side where the weight for forced subsidence is provided. To do. This allows
When the floating sinking and sinking wave sinker sinks into the water, the bag body is not bent extremely.

Further, according to the float-sink wave absorber according to the second aspect, since the bag body is made of a tubular member, the bag body can be easily manufactured and air can be smoothly supplied and exhausted. It is possible because it is possible. Moreover, since the bag body is composed of a pair of tube-shaped members arranged and connected in parallel to each other in the water surface direction, one of the tube-shaped members cancels the wave on the water surface, and then the other tube. The wave-shaped member can be used to break the wave, and the wave can be broken more effectively. Further, since the canvas is attached to each of the pair of tubular members, it is possible to effectively suppress the flow of water flow in water due to the influence of waves, and to more effectively prevent the diffusion of mud and the like. be able to.

In particular, according to the float-sink wave absorber according to the third aspect, the distance between the pair of tubular members is set to 5 m or more, so that the pair of tubular members simultaneously move up and down on the wave. You can avoid doing it. Because, from experience, the wavelength of the wave generated on the sea where this type of wave breaker is used is within 10 m, so if the interval between the pair of tubular members is set to be half the wavelength or more, This is because even if one of the tubular members moves up and down on a wave, the other tubular member does not move up and down in conjunction with the one tubular member. Therefore, the water flow in water can be suppressed by one of the canvases, and the diffusion of mud and the like due to the influence of waves can be surely prevented.

Further, according to the float-sink wave absorber according to the fourth aspect, since the length from the upper end to the lower end of the canvas is set to 4 m or more, the wave energy by the canvas is effectively attenuated. You can Because, the water particles inside the wave also have a rotational motion, and the motion of the water particles empirically extends to a depth of about a half wavelength below the water surface. The velocity of these water particles is the highest near the water surface, and decreases linearly as the water depth increases. Also, the energy of the wave is proportional to the square of the velocity of the water particle. Therefore, the length of the canvas is 4m below the water surface.
, The canvas can affect 80 percent of the velocity distribution of the water particles, assuming that the wavelength of the wave is up to 10 m. That is, if the length of the canvas is set to 4 m or below the water surface, the canvas can affect about 96% or more of the energy of the waves. Therefore, it is possible to more effectively prevent the diffusion of mud and the like due to the influence of waves.

[0016]

Embodiments will be described in detail below with reference to the accompanying drawings showing embodiments. FIG. 1 is a partially sectional exploded perspective view schematically showing a floating-sink type wave canceller according to an embodiment of the present invention. With reference to FIG. 1, this floating and sinking type wave-dissipating body is installed on the water to divide a construction area during underwater construction, and is a long bag body capable of being filled with air inside. 100, canvas 200 attached to the bag body 100, and hose 300
Has an air supply / exhaust device (not shown) connected to the bag body 100.

The bag body 100 includes a pair of tubular members 110 and 120 arranged in parallel, a connecting member 130 for connecting these members, and forcible sinking provided at one end of each of the tubular members 110 and 120. And a weight 140. The tubular members 110 and 120 are made of a flexible material such as rubber, and when they are filled with air, the tubular members 110 and 120 expand to form a cylindrical shape, and when the air is evacuated from the inside, the tubular members 110 and 120 shrink. This tubular member 11
The outer diameter of 0,120 is preferably set in the range of 300 mm to 700 mm, because it is hardly affected by the weight increase due to the attached organisms even when installed on the sea. Further, the tubular shape facilitates the manufacture of the bag body 100, can reduce the manufacturing cost, and can smoothly supply and exhaust air to and from the tubular members 110 and 120, which is preferable. .

The materials for forming the tubular members 110 and 120 are rubber, as well as the tubular members 110 and 1.
As long as the airtightness of the inside of 20 can be secured, a resin or the like can be used, or a cloth coated to secure the airtightness of the inside can be used. Further, the pair of tubular members 110 and 120 have a predetermined axial distance d in the water surface direction in the expanded state. In this embodiment, this distance d is set to 5 m. In addition,
The weight 140 for forced subsidence is made of metal such as lead or iron.

The connecting member 130 is in the form of a flexible sheet. The connecting member 130 is made of the same material as the material forming the tubular members 110 and 120. Thus, the tubular member 11
When the same material as 0 and 120 is used, they can be integrally formed. However, the connecting member 13
0 may be made of a material different from that of the tubular members 110 and 120. In this case, the tubular members 110 and 120 and the connecting member 130 may be connected by an adhesive or other known method. it can.

The canvas 200 is a sheet-like member having a rectangular shape, and its upper side 220 is attached along the longitudinal direction of each of the tubular members 110, 120. A weight 210 is provided on the lower side 230. In the present embodiment, the weight 210 is made of a chain, but may be made of a known one that can be used as a weight, such as lead or a concrete block. Further, the upper side 220 and the lower side 230 have a predetermined distance L, which is set to 4 m in this embodiment.

The air supply / exhaust device includes an air supply / exhaust portion and the hose 300. The air supply / exhaust unit is installed at a predetermined position on land, and the air supply / exhaust unit is connected to the tubular members 110, 120 by the hose 300. Then, by the air supply / exhaust unit, the hose 30
Air is supplied to the inside of the tubular members 110 and 120 via the
The inside air can be taken in and exhausted. Further, the hose 300 may be individually connected to the air supply / exhaust section, or a valve may be provided at a predetermined position so that air is uniformly supplied to both the tubular members 110 and 120. . By doing so, both the tubular members 11 can be used when air is supplied to levitate the wave-eliminating body.
0, 120 floats evenly, and tubular members 110, 1
It is possible to prevent the 20 pieces from contacting each other and being damaged.

According to this embodiment, when air is supplied to the pair of tubular members 110 and 120 by the air supply / exhaust device, the tubular members 110 and 120 become so-called floats and float above the water. By these tubular members 110 and 120, the wave on the water surface is canceled and the wave in the work area can be suppressed. Moreover, since these tubular members 110 and 120 are a pair of members arranged and connected in parallel to each other, for example, in FIG. 1, the wave traveling in the direction of arrow P is one tubular member 1
After being attenuated and dissipated at 10, the sufficiently attenuated wave that has passed through this tubular member 110 is further dissipated at the other tubular member 120, so that it can be effectively dissipated.

Since the canvas 200 is attached to each of the tubular members 110 and 120 along the longitudinal direction thereof, if the tubular members 110 and 120 float,
The canvas 200 is suspended in water by a weight 210. With this canvas 200, it is possible to suppress the flow of water in the water, and in combination with the wave-dissipating of the water surface by the tubular members 110 and 120, mud and the like generated in the water during dredging work are diffused due to the influence of waves, It is possible to prevent leakage from the construction area to the outside. Moreover, since the canvas 200 is attached to each of the tubular members 110 and 120, the pair of tubular members 110,
Similar to the wave extinction by 120, mud and the like can be effectively prevented from leaking from the construction area to the outside.

On the other hand, when the air inside the tube-shaped members 110 and 120 is exhausted by the air supply / exhaust device, the tube-shaped members 110 and 120 have flexibility and contract, and their buoyancy decreases. . Also referring to FIG. 2 at the same time, since the weight 140 for forcible sinking is provided at one end of each of the tubular members 110, 120, the tubular members 110, 120 with reduced buoyancy.
Does not bend extremely in order from one end side where the weight 140 for forced subsidence is provided, and smoothly submerges in water. As a result, the floating sinking and sinking wave sinker is submerged in water,
Alternatively, even if the floating is repeated again, the tube-shaped members 110 and 120 are not damaged, and the floating-sink type wave breaker has extremely excellent durability. Moreover, there is no need for conventional equipment for bleeding air from both ends of each tubular member 110, 120, and the float-sink wave breaker can be easily sunk or floated.

In particular, in this embodiment, since the axial distance d between the pair of tubular members 110 and 120 is set to 5 m, the pair of tubular members 110 and 120 simultaneously move up and down on waves. You can avoid doing it.
This is because, from experience, the wavelength of the wave generated at sea is usually within a maximum of 10 m, and the pair of tubular members 1
If the axial distance d of 10, 120 is set to ½ or more of the wavelength of the wave generated on the water surface, even if one of the tubular members moves up and down on the wave, the other tubular shape This is because the member can be prevented from moving up and down in conjunction with the one tubular member. Therefore, the water flow in the water can be suppressed by one of the canvases 200, and the diffusion of mud and the like due to the influence of waves can be reliably prevented.

Moreover, since the length from the upper side to the lower side of the canvas 200 is set to 4 m, the canvas 200 can effectively attenuate the energy of the wave passing through the floating-sink wave absorber. Because the water particles inside the wave are
It also has a rotating motion, and the motion of this water particle is, from experience,
It extends to a depth of about half a wave below the surface of the water. The velocity of this water particle is
It is the fastest near the water surface and decreases linearly as the water depth increases. Also, the energy of the wave is proportional to the square of the velocity of the water particle. Therefore, the length of the canvas 200 should be 4
If set to m, the maximum wavelength of the wave is 10 m,
The canvas 200 can affect 80 percent of the velocity distribution of water particles. That is, canvas 200
Can affect more than about 96 percent of the wave energy.

Therefore, each of the above dimensions is a preferred embodiment in which a significant wave-dissipating effect can be obtained. Next, the result of the comparative wave-dissipation experiment of the float-sink type wave-dissipating body according to the present invention will be shown. A wave-dissipation experiment was conducted on a floating-sink type wave-dissipating body of the type shown in FIGS. Of these, the float-sink wave absorber according to the present invention is of the type shown in (c), and the above-mentioned dimensions are: the outer diameter of the tubular member S = 150 mm, the axial distance d = 500 mm, the canvas length L = 500 mm.

On the other hand, (a), (b) and (d)
The type shown in (3) was used in a comparative experiment for the floating-sink type wave breaker of the type (c). Explaining each type, in the type (a), the outer diameter S and the canvas length L of the tubular member are the same as those in the type (c), but a single type is used. It is composed of a tubular member and canvas. In the type (b), the outer diameter S, the axial distance d, and the canvas length L of the tubular member are the same as those in the type (c), but the canvas is of a single type. The small floating body T is provided instead of the tubular member on the side to which the canvas is not attached. Further, a connecting member made of the same material as the above-mentioned canvas is attached between the tubular member and the small floating body T. Furthermore, the type (d) is
It is a modification of type (a), which doubles the length of the canvas,
A rubber body G having the same outer diameter as the outer diameter S of the tubular member is attached in the middle of the canvas. The rubber body G has a hollow structure, and water is sealed inside.

Under the above-mentioned conditions, each of the floating-sink wave absorbers was floated on the water surface having a sufficient water depth, and waves of various wavelengths were generated to investigate the wave-dissipating effect. FIG. 4 is a graph of the results, in which the horizontal axis represents the wave period and the vertical axis represents the transmittance of the given wave. In addition, between the period t of the deep sea wave and the wavelength λ,

[0030]

## EQU1 ## There is a relationship of λ = 1.56t ² -------------. Comparing the types of (a) and (b) with the type of (c) with reference to FIG. 4, it is clearly superior that the tubular member and the canvas are provided in a pair rather than a single one. It shows the wave breaking performance. Moreover, as compared with the type (d), it can be seen that the wave-dissipating effect is higher when the tubular members are connected in parallel so that the tubular members are parallel to each other in the water surface direction than when they are connected in series in the water depth direction.

Further, since the axial distance dimension and the canvas length dimension are set to 500 mm, the formula (I) can theoretically affect waves having a period of 0.8 seconds or less. It should be possible, and the type (c) above was able to obtain the wave-dissipation effect that most closely matched the theory. From the above experimental results, if the wavelength of the wave that normally occurs on the sea is 10 m, in order to effectively cancel the wave having this wavelength, the inter-axis distance dimension and the canvas length dimension according to the above embodiment Setting it to proves that it is effective.

[0032]

According to the first aspect of the present invention, when the air in the bag is exhausted by the air supply / exhaust device, the bag contracts to reduce its buoyancy, and one end provided with the weight for forced subsidence. Settle into the water from the side. This prevents the bag body from being extremely bent when the float-sink wave absorber is submerged in water, and can prevent damage even if the float-sink wave absorber is repeatedly floated and lowered. Moreover, since the air supply / exhaust device is connected only to the other end side of the bag body, the device can be simplified and the cost of the floating / sink-type breaker can be reduced as compared with the conventional device.

According to the second aspect of the present invention, since the bag body is made of a tubular member, it is easy to manufacture the bag body, and thus the float-sink wave absorber can be provided at a low cost. it can. Moreover, since the pair of tubular members are provided in the water surface direction and the canvas is attached to each of the pair of tubular members, after the wave on the water surface is canceled by one of the tubular members. Further, the other tubular member can be used to cancel the wave, and the flow of the underwater due to the influence of waves can be effectively suppressed, so that the underwater work can be easily performed.

In particular, according to the third aspect of the invention, since the distance between the pair of tubular members is set to 5 m or more, a wavelength of 10 m which is usually generated on the sea where this type of wave breaker is used. The following waves can be effectively canceled, which is preferable. Furthermore, since the length from one end to the other end of the canvas is set to 4 m or more in the invention of claim 4, the wavelength 1 which is usually generated on the sea where this type of wave breaker is used is
The kinetic energy of water particles in the depth direction due to waves of 0 m or less can be effectively attenuated to effectively prevent the diffusion of mud and the like due to the influence of waves, so that underwater work is further facilitated. be able to.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional perspective view showing a schematic configuration of a float-sink wave absorber according to an embodiment of the present invention.

FIG. 2 is a front view showing a sinking state of the floating-sink type wave breaker.

FIG. 3 (a) used in a comparative wave-dissipation experiment of a floating-sink type wave-dissipating body
It is a schematic diagram of the float-sink type wave breaker of the type of (d).

FIG. 4 is a graph showing the results of a comparative wave-dissipation experiment of the floating-sink type wave-dissipating body.

FIG. 5 is a partial cross-sectional perspective view showing a conventional float-sink wave absorber.

FIG. 6 is a front view showing a sinking state of a conventional float-sink type wave breaker.

[Explanation of symbols]

 100 bag 110 tube-shaped member 120 tube-shaped member 130 connection member 140 forced sinking weight 200 canvas 210 weights 300 hose

Claims (4)

[Claims] 1. A long bag which is flexible and floats above water by being filled with air, and an upper end attached along the longitudinal direction of the bag and a weight at the lower end. Is provided to suppress the flow of water in water due to the influence of waves by hanging from the bag body into the water; an air supply / exhaust device for supplying or exhausting air to the bag body; In a floating sinking and sinking wave canceller equipped with a sinking weight for forcibly submerging the bag body and canvas in water when the air in the bag is exhausted by the device, the forced sinking weight is the bag. A float-sink type wave breaker, which is provided at one longitudinal end of the body, and the air supply / exhaust device is connected to the other longitudinal end of the bag. 2. The bag body is composed of a pair of tube-shaped members connected in parallel with each other in the water surface direction while floating on the water. Each of the pair of tube-shaped members has a longitudinal direction. The float-sink wave absorber according to claim 1, wherein the canvas is attached along the same. 3. The distance between the pair of tubular members is 5 m.
The floating and sinking type breaker according to claim 2, wherein the above is the above. 4. The length from the upper end to the lower end of the canvas is 4
The above-mentioned claim 1 to 3 characterized in that it is m or more.
Floating and sinking wave absorber described.