JP2002180435A - Curtain type breakwater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a curtain type breakwater that can effectively dissipate waves even if the nature of object waves to be dissipated is changed after the installation of the breakwater. SOLUTION: This curtain type breakwater with a wall body installed near the sea surface above pile bodies 5 erected on the sea bottom ground, is provided with a port outside wall body 7 with an opening, and a port inside wall body 9 installed behind the port outside wall body 7, and a space between the port outside wall body 7 and the port inside wall body 9 is changeable.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a curtain type breakwater having a wall near a water surface installed in a fishing port or a harbor.

[0002]

2. Description of the Related Art For breakwaters in fishing ports and harbors where the waves are relatively gentle and the seabed is soft, a curtain system is used to improve the calmness of the harbor by providing walls near the water surface to improve the efficiency of use of the harbor. Breakwaters are used. This curtain type breakwater includes, for example, a so-called single curtain type breakwater having a single wall body disclosed in Japanese Patent Application Laid-Open No. 7-173813, and a so-called double curtain type breakwater having a double wall body in order to further enhance the wave breaking effect. Heavy curtain breakwaters are known.

FIG. 6 is an explanatory view of a conventionally known double curtain type breakwater. The double curtain type breakwater comprises a pile 33 erected on the seabed ground and reinforced with abandoned stones 31, a front wall 37 installed on the outside of the port 35 of the pile 33, and a front wall 3
Rear wall 3 installed behind front wall 37 at a predetermined distance from front wall 37
9 and a superstructure 41.

[0004] The distance between the front wall 37 and the rear wall 39 is set so as to exhibit an effective wave canceling performance with respect to the period of the wave to be canceled. It is known that by setting this interval to 10 to 20% of the wavelength of the wave to be canceled, the reflectance of the wave can be minimized.

[0005]

However, after the curtain type breakwater is installed in the harbor, the wake wave generated by the navigation of the ship due to the construction of the offshore breakwater accompanying the offshore development of the outer shell facilities and the change of the type of the navigating ship. , The period of the target wave may change from before the curtain breakwater is installed. Thus, when the period of the wave to be canceled changes, sufficient wave-damping performance cannot be exhibited unless the wall interval is changed. However, the conventional double curtain type breakwater has a problem that the wall interval cannot be changed, and effective wave-elimination cannot be performed on the wave to be canceled after the change.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and provides a curtain type breakwater capable of effectively breaking even if the property of the wave to be broken changes after the breakwater is installed. It is intended to be.

[0007]

According to the present invention, there is provided a curtain type breakwater in which a wall body is installed near an upper sea surface of a pile body erected on the seabed ground, wherein a port outer wall body having an opening is provided. A harbor inner wall provided behind the harbor outer wall, wherein a distance between the harbor outer wall and the harbor inner wall is changeable.

[0008] Further, the inner wall of the port is opaque.

[0009] Further, the inner wall of the port has permeability.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a side view of a curtain breakwater according to the present embodiment, and FIG. 2 is a front view. The curtain-type breakwater 1 is movably installed on a support pile 5 erected on the support ground 3, a front wall 7 installed above the support pile 5 on the outside of the port 4, and behind the front wall 7 (inside the port 8). And a superstructure 11 provided at the upper end of the support pile 5.

In this example, two support piles 5 are provided outside the harbor,
Two are installed inside the port, for a total of four. The support pile 5 penetrates the soft ground 13 on the sea floor and is erected on the support ground 3, and the horizontal resistance is enhanced by the waste stone 15 laid on the sea floor.

As shown in FIG. 2, the front wall 7 is supported and installed by a steel pipe 17 laid on the left and right support piles 5 and a support member 19 attached to the support pile 5. Front wall 7
Is provided with a plurality of slit-shaped openings 7a which are long in the vertical direction.

As shown in FIG. 1, the rear wall 9 is installed on a steel pipe 21 installed on the support pile 5 outside the port and the support pile 5 inside the port. FIGS. 3A and 3B are explanatory views of the rear wall 9. FIG. 3A is a front view of the rear wall 9, and FIG.
It is a side view in the attached state. The rear wall 9 is shown in FIG.
As shown in (a), a frame 9a, a wall body 9c formed with a plurality of vertical slit-shaped openings 9b,
It is composed of a mounting portion 9d formed of a tubular body that can be inserted into the steel pipe 21 provided at the corner.

The mounting structure of the rear wall 9 will be described. After the mounting portion 9d is inserted into the steel pipe 21 to set the position of the rear wall 9, the mounting portion 9d is mounted as shown in FIG.
The front and rear of d are fixed by the fixing member 23. As shown in FIG. 4, the fixing member 23 has a flange portion 23 on one end side.
This is a member obtained by halving a cylindrical body having a, and is fixed to the steel pipe 21 by sandwiching the steel pipe 21 so as to surround the steel pipe 21 from the circumferential direction and connecting the half members by bolts 23b. Rear wall 9
Is fixed at a predetermined position by being sandwiched between the front and rear by the fixing member 23.

Next, the operation of the present embodiment configured as described above will be described. When the curtain-type breakwater 1 is launched, the rear wall 9 is placed close to the rear support pile 5 side (see FIG. 1). At this time, the distance between the front wall 7 and the rear wall 9 is set so as to be 10 to 20% of the wavelength of the wave to be canceled, and the wave to be effectively canceled at the time of launching. I can do it. In this state, the wave incident on the curtain breakwater has the front wall 7 and the rear wall 9 blocking the vicinity of the water surface where the water particle movement is intense, and passes through the openings 7a and 9b of the front wall 7 and the rear wall 9. As a result, the reflectance is suppressed due to energy loss due to the vortex, mutual interference between the incident wave and the reflected wave, and the like.

[0016] Thereafter, when the wave to be canceled changes from an open sea wave to a harbor wave due to the completion of an offshore breakwater, the period of the wave becomes shorter, and it is necessary to effectively cancel the wave in the harbor. It becomes necessary to reduce the distance between the front wall 7 and the rear wall 9. Then, the fixing member 23 is removed, and as shown in FIG.
Is moved to an appropriate position in front and is fixed again by the fixing member 23. As a result, the wall interval is adjusted so as to be effective for the extinction of the new wave to be canceled, and effective extinction can be achieved for the wave whose period has changed.

As described above, according to this embodiment, even if the period of the wave to be canceled is changed due to the completion of the offshore breakwater after the breakwater is launched, the wave to be changed is not affected by the wall. The distance between the bodies can be easily changed to an appropriate distance for the wave to be canceled.

In the above embodiment, an example in which the rear wall 9 is provided with the slit-shaped opening 9b is shown. This is to prevent the water flow from being completely blocked by the curtain breakwater, and to prevent the deterioration of the water quality inside the port. However, in the case of the curtain type breakwater, since the lower part of the wall is open only by the support pile 5, the deterioration of the water quality inside the port is not so large. Therefore, an opaque wall body having no opening in the rear wall 9 can be used. By using an impermeable wall, the transmitted waves can be further reduced and the inside of the harbor can be kept calm.

The materials of the front wall 7 and the rear wall 9 are not particularly limited, and may be made of concrete or steel.

[0020]

As described above, according to the present invention, a port outer wall having an opening and a port inner wall provided behind the port outer wall are provided, and the port outer wall and the port inner are provided. By changing the distance between the side walls, even if the characteristics of the target wave change after launching the breakwater, changing the distance between the outer wall and the inner wall of the harbor facilitates the wave breaking performance. Can be maintained.

[Brief description of the drawings]

FIG. 1 is a side view of a curtain breakwater according to an embodiment of the present invention (at the time of launch).

FIG. 2 is a front view of a curtain breakwater according to an embodiment of the present invention.

FIG. 3 is an explanatory view of an intermediate wall of a curtain breakwater according to one embodiment of the present invention.

FIG. 4 is an explanatory view of a fixing member of an intermediate wall of a curtain breakwater according to one embodiment of the present invention.

FIG. 5 is a side view of the curtain breakwater according to one embodiment of the present invention (when the wall interval is changed).

FIG. 6 is an explanatory view of a conventional double curtain type breakwater.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Curtain breakwater 5 Support pile 7 Front wall 7a, 9b Opening 21 Steel pipe

Claims (3)

[Claims] 1. A curtain-type breakwater having a wall installed near an upper sea surface of a pile body erected on the seabed ground, wherein a port outer wall having an opening and a port installed behind the port outer wall are provided. A curtain-type breakwater, comprising a side wall body, wherein a distance between the port outer wall body and the port inner wall body can be changed. 2. The curtain breakwater according to claim 1, wherein the inner wall of the port is impermeable. 3. The curtain breakwater according to claim 1, wherein the inner wall of the port has permeability.