JP5915997B2 - Wave-proof structure - Google Patents

Description

  The present invention prevents and reduces the damage caused by a wave-breaking structure installed for tanks for storing stored liquids such as oils and liquid dangerous substances having a specific gravity lower than water, especially tsunami and high waves. It is related with the wave-proof structure for doing.

As is well known, for example, a breakwater or a tide bank of a type called a movable type or a floating type as disclosed in Patent Documents 1 to 4 has been proposed as a breakwater structure against a tsunami or a high wave.
These have a structure in which various floating bodies are stored in the levee body or lying on the seabed, and in the event of an emergency, these floating bodies are levitated on the sea surface to exert a wave-breaking function.

JP 2006-249914 A JP 2006-241806 A JP 2006-70536 A JP 2004-76393 A

  Large-scale tanks for storing stored liquids such as oils and liquid hazardous materials are surrounded by a breakwater to prevent the stored liquid from flowing out and spreading due to the damage of the tank. There is a need to prevent.

  FIG. 3 shows an example of installing a breakwater for a conventional general tank. This is because the ground-type tank 1 having a circular horizontal cross section as shown in (a) is installed on the foundation 2 and has a substantially square outline surrounding the tank 1 all around it. The bank 3 is installed.

  In this case, as shown in (b), the height H (dimension from the ground surface to the top edge) of the breakwater 3 is such that the entire amount of the liquid stored in the tank 1 can be stored inside the breakwater 3. (That is, even if the entire amount of the stored liquid leaks from the full tank 1, it is set so as not to overflow the liquid barrier 3). That is, when the maximum storage capacity V of the tank and the area A in the breakwater are set, H> V / A is set.

  By the way, this type of tank 1 is often installed in the coastal area, and in such a case as well, a conventional dike 3 having a general structure as shown in FIG. 3 is installed. The liquid bank 3 does not have a protection performance against a large tsunami or high wave that flows over the top of the bank, and cannot function effectively when such a tsunami or high wave strikes.

For this reason, in the previous Great East Japan Earthquake, a tsunami that exceeded the expected level easily overcame the breakwater, destroying the tank and attached piping, and the stored liquid such as oil spilled from the tank spread over a wide area along with the tsunami. Caused damage.
In addition, the tank was not only damaged by the tsunami wave force, but the entire submerged tank floated and drifted due to buoyancy, and the drifting object drifting with the tsunami hit the tank directly. It is thought that there were cases where it was destroyed and it spread damage.

  In this way, simply installing a conventional breakwater for a large tank installed in the coastal area is vulnerable to large-scale tsunamis and high waves. The actual situation is that there is an urgent need for effective measures to improve the safety and reliability of emergency tanks and reduce damage.

  In view of the above circumstances, the present invention has the function of a movable or levitated breakwater or tide embankment as shown in Patent Documents 1 to 4 with respect to a conventional general breakwater installed in this type of tank. By adopting it, even if the tank is damaged in the event of an emergency such as a large-scale tsunami or high wave, it is possible to effectively prevent and reduce the situation such as diffusion of the stored liquid to the surroundings. Is.

That is, the invention according to claim 1 is a wave protection for preventing and reducing emergency damage caused by a tsunami or a high wave for a tank for storing a liquid having a specific gravity lower than that of water or a liquid dangerous substance. It is a structure, and is stored in a liquid breakwater that surrounds the tank, and in a storage portion formed at the top of the liquid breakwater, and can float on the water surface in an emergency and around the tank A levitating type liquid fence that can be deployed, and a mooring line for mooring the levitated type liquid fence to the ground around the liquid bank or the tank, A float that can float on the water surface from the storage when the liquid breakwater is submerged, and a fence body that is suspended and supported by the float in the event of an emergency and is disposed near the water surface and deployed around the tank. Structure It is characterized by comprising.

  The invention according to claim 2 is the wave-breaking structure according to claim 1, wherein the floating liquid fence and the mooring line have a mooring function for preventing drifting of the tank that has levitated in an emergency. Features.

  Invention of Claim 3 is the wave-proof structure of Claim 1 or 2, Comprising: The said levitation-type liquid fence is a buffer function which eases the impact force at the time of a drifting object colliding with the said tank at the time of emergency It is characterized by having.

By installing the wave-breaking structure of the present invention around the tank, not only does it have the same liquid-proof function as a conventional liquid-proof wall, but also large-scale tsunamis and high waves strike during normal times. In the event of a submergence of the breakwater, the floating breakwater fence stored in the breakwater storage section will naturally float on the surface of the water and be deployed to surround the entire tank. .
Therefore, in such a case, even if the tank is damaged and the stored liquid leaks from the tank to the outside, the leaked liquid remains only inside the floating liquid fence. It is possible to effectively prevent or greatly reduce the damage caused by the fact that a large amount of stored liquid is effectively prevented from diffusing over a wide area as it is, preventing it from flowing out to the outside. .
Further, according to the wave-breaking structure of the present invention, in the unlikely event that the tank is lifted, the entire tank can be moored by the floating liquid fence and the mooring line. It is possible to prevent a situation that drifts far away.
Furthermore, according to the wave-breaking structure of the present invention, it is possible to mitigate the impact when the drifting object collides with the tank by the floating liquid fence, and it is possible to reduce the damage to the tank. is there.

BRIEF DESCRIPTION OF THE DRAWINGS It is an elevation view which shows schematic structure of the breakwater structure which is embodiment of this invention, Comprising: (a) is the state at the time of normal, (b) is emergency (state where the breakwater was submerged at the time of tsunami attack) It is a figure which shows the state of. It is a top view which shows the state in the same time as emergency. It is a figure which shows the example of installation of a conventional general breakwater, (a) is a top view, (b) is an elevation.

Hereinafter, embodiments of the wave-proof structure of the present invention will be described with reference to FIGS.
The wave-breaking structure 10 according to the present embodiment is a large-scale tank 1 for storing a storage liquid such as oil or liquid dangerous substance having a specific gravity lower than that of water (strictly seawater). Even if damage such as leakage of stored liquid occurs in an emergency such as a tsunami or high wave, the situation where the stored liquid is diffused over a wide area by the wave-breaking structure 10 is avoided, and the outflow of the stored liquid is prevented. It is possible to sufficiently prevent and mitigate the damage caused by.

  The breakwater structure 10 of the present embodiment basically surrounds the entire tank 1 with a breakwater 11 having the same form and function as the conventional breakwater 3 shown in FIG. The storage unit 11a for storing the floating type liquid fence 13 is provided at the top of the liquid barrier 11 and the floating type liquid fence 12 is always stored in the storage unit 11a. The main focus is to keep.

The liquid breakwater 11 in this embodiment may have substantially the same structure and form as the conventional general liquid breakwater 3 except that the storage portion 11a is formed. What is necessary is just to install as what is equipped with the liquid-proof function (function which prevents the outflow to the circumference | surroundings of the stored liquid which should leak by any chance from the tank 1) like the general liquid-break wall 3.
However, the breakwater 11 in the breakwater structure 10 according to the present embodiment has an original function as a conventional conventional breakwater, and also when a tsunami or high wave of an assumed scale hits it. It is preferable to have strength that can be withstood, and at that time, the floating liquid fence 12 can be lifted without hindrance, and the function of the floating liquid fence 12 is not impaired. is necessary.

  As shown in FIGS. 1B and 2, the floating liquid fence 12 according to the present embodiment is disposed from the storage portion 11 a when the liquid breakwater 11 is submerged in an emergency when a large-scale tsunami or high wave hits. A float 12a that can naturally float on the surface of the water (on the surface of the tsunami or high wave that hits), and is supported by the float 12a in the event of an emergency and is located near the surface of the water (from the surface of the tsunami or wave of high waves to a predetermined depth). The fence body 12b can be developed around the tank 1.

As the float 12a in the present embodiment, any float can be used as long as it can be stored in the storage unit 11a in normal times and has a buoyancy that can float on the water surface and support the fence body 12b near the water surface in an emergency. Any type of floating body such as a body, an air bag, or a foam material can be used.
In addition, as the float 12a, it is possible to employ a type of air bag that is deflated at normal times and inflated instantaneously to ensure buoyancy by injecting gas such as air or gas in an emergency. .

  As the fence main body 12b in the present embodiment, various sheet materials and film materials that are generally used as an oil fence can be suitably used. However, the fence body 12b is normally stored in the storage portion 11a in a compactly folded state. In an emergency, it is arranged near the water surface in a state of being suspended and supported from the float 12a by being lifted and naturally expanded by the float 12a.

The entire floating type liquid fence 12 composed of the float 12a and the fence body 12b is connected to the liquid bank 11 by a plurality of mooring lines 13 (for example, eight as shown in FIG. 2). Moored.
Therefore, in the event of an emergency where the breakwater 11 is submerged due to a large-scale tsunami or high wave, the entire floating breakwater fence 12 naturally rises from the storage portion 11a as shown in FIG. It is arranged in the vicinity of the water surface in a state where it is unfolded so that the entire floating liquid fence 12 is moored by the mooring line 13 and stays in that position without drifting.
If the breakwater 11 has sufficient strength to withstand tsunamis and high waves as described above, the mooring line 13 can be fastened to the breakwater 11 as shown in the illustrated example. If there is a concern that the breakwater 11 may be damaged and the mooring line 13 cannot be securely moored in an emergency, the mooring line 13 is securely anchored to the ground near the breakwater 11. By doing so, it is preferable to ensure that the floating liquid fence 12 is moored around the tank 1 even if the liquid barrier 11 is damaged.

  As shown in FIG. 1A, the wavebreak structure 10 according to the present embodiment configured as described above is configured such that the entire floating type liquid fence 12 is accommodated in the upper storage portion 11 a of the liquid breakwater 11 as shown in FIG. By storing in a compact manner, the normal liquid-proof function by the liquid-proof bank 11 can be exhibited without any trouble as in the conventional general liquid-proof bank 3 shown in FIG.

In addition to the original function of the breakwater, in an emergency when a large tsunami or high wave hits and the breakwater 11 is submerged, FIG. 1 (b) and FIG. As shown in the drawing, the floating type liquid fence 12 stored in the storage unit 11a naturally floats on the water surface, and the fence body 12b is unfolded so as to surround the entire tank 1 near the water surface in a state of being suspended and supported from the float 12a. The
In this state, as shown in FIG. 1B, even if the tank 1 is damaged and the stored liquid leaks outside from the tank 1, the leaked liquid L is floated. The inside of the fence 12 stays floating on the water surface and is prevented from flowing out to the outside. Therefore, it is effectively prevented that a large amount of stored liquid in the tank 1 is diffused as it is in a wide range. It is possible to sufficiently prevent or significantly reduce the damage caused thereby.
Assuming that the tank 1 in the full liquid state is damaged, it is preferable to reliably prevent the outflow of all the stored liquid stored at that time, as shown in FIG. 1 (b). It is preferable to set the height dimension of the portion that is submerged under the surface of the water at the time of deployment of the floating type liquid fence 13 so as to correspond to at least H or more shown in FIG. Thereby, even if the entire amount of the stored liquid stored in the tank 1 is leaked to the maximum, the leaked liquid L can be surely prevented from diving through the lower part of the fence body 12b and diffusing to the surroundings. Can do.
Of course, after the tsunami has ended, the leaked liquid L remains in the vicinity of the tank 1 and may be collected and discharged as appropriate.

In addition, in the case of a large-scale tsunami, it is assumed that the entire tank 1 receives a large buoyancy and floats on the foundation 2. However, if the wave-breaking structure 10 according to the present embodiment is installed, such a situation occurs. Even in such a case, the levitation-type liquid fence 12 and the mooring line 13 exert a mooring function with respect to the tank 1, so that the worst situation in which the floated tank 1 drifts as far as it is can be prevented. It is.
However, in order for the wave-breaking structure 10 of the present embodiment to effectively exhibit the drift prevention function for the tank 1, the floating liquid-proof fence 12 and the mooring line 13 are resistant to the wave force of the tsunami. Of course, it is necessary to install it as having sufficient strength for mooring.

Furthermore, in the case of a large-scale tsunami, there is a concern that various drifting objects drifting along with the tsunami may directly hit the tank 1 and damage the tank 1. The liquid fence 12 can be provided with a buffering function for relaxing and preventing damage by mitigating the impact force when the drifting object collides with the tank 1.
For this purpose, the float 12a is, for example, the same as a conventional general fender, and the float 12a is provided with sufficient strength and buffering function (for example, a foam material having sufficient buoyancy and strength). It is preferable that the material of the fence main body 12b is also provided with such a buffering function.
Even if the levitation-type liquid fence 12 is destroyed in the event of a tsunami or high wave exceeding the expected scale, the wave power can be reduced compared with the case where only the liquid breakwater 11 is installed. It can be expected that the effect of reducing the moving distance when the tank 1 floats and the effect of preventing the collision of drifting objects are enhanced.

  As mentioned above, although one embodiment of the present invention was described, the above-mentioned embodiment is a suitable example to the last, and the present invention is not limited to the above-mentioned embodiment. For example, the form, structure, scale, and liquid prevention of the tank 1 As for the specific configurations and the like of the dam 11, the floating type liquid fence 12, and the mooring line 13, it is natural that appropriate design changes and applications can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Tank 2 Foundation 10 Breakwater structure 11 Liquid breakwater 11a Storage part 12 Levitation type liquid fence 13a Float 12b Fence body 13 Mooring line

Claims (3)

A wave-breaking structure for preventing and mitigating emergency damage caused by tsunamis and high waves for tanks that store liquids with lower specific gravity than water and liquid hazardous materials,
A floating breakwater that surrounds the tank and is stored in a storage section formed on the upper portion of the breakwater, and can float on the water surface in an emergency and can be developed around the tank. A liquid fence and a mooring line for mooring the floating liquid fence to the ground around the liquid breakwater or the tank;
The floating liquid fence is floated on the surface of the water when the liquid breakwater is submerged, and is suspended and supported by the float in the event of an emergency and is disposed near the water surface and around the tank. A wave-breaking structure characterized by comprising a fence main body that can be deployed on a wall. The wave-breaking structure according to claim 1,
The levitation-type liquid fence and the mooring line have a mooring function for preventing drifting of the tank that has levitated in an emergency. The wave-breaking structure according to claim 1 or 2,
The levitation-type liquid fence is characterized by having a buffering function to reduce an impact force when a drifting object collides with the tank in an emergency.

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