JP2003253643A - Column maintenance device in marine structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a column maintenance device capable of preventing or reducing the attachment of living matters, expecting the persistence of the effect with an inexpensive and simple device, simplifying the execution, and being easily applied to an existing structure, with respect to a marine structure having a column. <P>SOLUTION: In this column maintenance device in the marine structure having roller-shaped columnar members having buoyant force and abutted on a peripheral face of the column are annularly connected by connecting members having elastic force to be mounted on an outer periphery of the column. Columnar members not having buoyant force are similarly annularly connected by connecting members having elastic force, and suspended by the side of the columnar members having the buoyant force through vertical connecting members. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a floating structure which has a floating column and is floated on the sea surface, or a fixed structure which is fixed to the sea floor and has a support column for supporting a platform on the sea surface. Related to column maintenance equipment for offshore structures.

[0002]

2. Description of the Related Art Conventionally, an offshore structure having a column of this type has been manufactured and used as an oil drilling rig, a marine work platform, a jetty, a breakwater, etc. in the ocean. Recently, there is a concept of enlarging an offshore structure and using it as a disaster prevention base or an airport in the event of a disaster, and various developments and researches are being advanced toward practical use.

An offshore structure having columns has the advantage of being strong against waves because it does not completely block the flow of water on the surface of the sea and the force it receives from waves is small. However, because of the structure having many columns, the total area of the splash zone centering on the waterline becomes large.

[0004] In the splash zone, that is, in the part that is immersed in seawater or exposed to the air, aquatic animals and plants (hereinafter referred to as organisms) such as algae and shellfish adhere to with the passage of time during use. Come on.

Such attached organisms may erode the painted surface of the column and adversely affect the surface of the column. Also,
Adhering a large amount increases the apparent size of the column, which affects the hydrodynamic performance of the floating structure. Furthermore, if a large amount of adherence and the collapse of adherents are repeated, the environment of the structure installation sea area may change, and the adherence of living organisms is a problem for long-term durability of marine structures. .

[0006] Conventionally, as a method for preventing the adhesion of this organism, a method of coating a paint containing copper, a copper alloy, or an electromagnetic material, or an organic antifouling agent such as tannin, titanium, a copper alloy, etc. A method of adhering an antifouling material to a surface in contact with seawater, a method of jetting pressurized water vapor to adhered organisms, or a method of mechanically removing by applying an impact by electric discharge have been developed and proposed.

However, there are problems that the effect is short-lasting, expensive materials are used, workability is poor, or a large-scale construction device is required.
Therefore, it is not an effective measure as a whole because it is not economical for an offshore structure having a column with a large total area of the splash zone, and there are methods that cannot be applied to existing structures.

[0008]

DISCLOSURE OF THE INVENTION The present invention is an offshore structure having a column, which can prevent or reduce the adhesion of living organisms, is a low-priced and simple device, can expect a long-lasting effect, and is easy to construct. The purpose of the present invention is to obtain a column maintenance device that can be easily applied to existing structures.

[0009]

A column maintenance device for an offshore structure having a column, comprising a roller-shaped columnar body having a buoyancy and being divided into a large number of pieces and contacting a peripheral surface of the column. It was connected in an annular shape with a connecting material having and was arranged on the outer periphery of the column. Further, the columnar bodies having no buoyancy are connected in an annular shape by a connecting material having elastic force similarly, and the columnar bodies having the buoyancy are hung from the columnar body via the upper and lower connecting materials.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic side view of a column provided with a column maintenance device according to the present invention, FIG. 2 is a plan sectional view of the same, FIG. 3 is a view showing a swing state of the column maintenance device, and FIG.
5 is a horizontal sectional view of the columnar body, and FIG. 5 is a vertical sectional view thereof. FIG. 6 is a diagram showing an example in which a columnar body having no buoyancy is provided, FIG. 7 is a diagram showing an example in which a connecting member is provided with a spring, and FIG. 8 is a schematic diagram of a marine structure targeted by the present invention.

Reference numeral 1 denotes a marine structure targeted by the present invention. A floating column 3 is erected on a lower hull 2, and a semi-sub type floating structure in which an upper platform 4 is supported by the floating column 3 on the sea surface. Is. The cross-sectional shape of the floating body column 3 is cylindrical as shown in FIG.
As shown in (B), a rectangular tube having a corner with an R is normally used.

Reference numeral 5 denotes a roller-shaped columnar body having buoyancy, which is divided into a large number of pieces having an appropriate width along the outer surface of the column 3. In addition, a material such as a rubber material or a resin material that does not damage the surface of the column 3 is used, and has a structure having buoyancy so as to follow the vertical movement of the wavefront. In the example shown in the figure, an air chamber is formed inside because it has buoyancy. The column 3 has a diameter of about 10 m in many cases, whereas the columnar body 5 has a diameter of about 0.5 to 1 m.

Reference numeral 7 is a connecting member for connecting the columnar members 5 in an annular shape, and a connecting member having an elastic force is used. As will be described later, the columnar body 5 is connected in an annular shape and is arranged so as to be in slight contact with the outer periphery of the column 3, but oscillates following the movement of waves. It is sufficient that the connecting member 7 can be slightly expanded and contracted to the extent that this swinging is allowed. For example, a rubber-like material used for the fender in the form of a rod or an ocean rope such as an oil fence is used. Further, as shown in FIG. 7, a steel material may be connected by a spring 8.

The columnar bodies 5 are connected by a connecting member 7 so that they can be individually rotated via a bearing such as a bearing 9.
In FIG. 6, 10 is a columnar body having the same shape as the columnar body 5 but having no buoyancy, and is suspended from the columnar body 5 side by, for example, upper and lower connecting members 11 such as chains. , Submerged in the sea. Reference numeral 12 is a connecting member of the columnar body 10 and has the same structure as the connecting member 7 of the columnar body 5. The upper and lower connecting members 11 are connected to the connecting member 7 of the columnar body 5 and the connecting member 12 of the columnar body 10.

The configuration of the present invention is as described above, and its operation will be described below. First, as shown in FIG.
A columnar body 5 connected in an annular shape by a connecting member 7 is arranged along the outer peripheral surface of the column 3. At this time, since the columnar body 5 has buoyancy and the connecting member 7 has elastic force, the columnar body 5 floats on the sea surface and is in a state of lightly contacting the outer peripheral surface of the column 3.

When a wave is applied to the column 3 from this state, the columnar body 5 oscillates following the wave as shown in FIG. That is, the columnar body 5 rolls on the outer surface of the column 3 according to the wave period and moves up and down along the surface. By the vertical movement of the columnar body 5, the outer surface of the column 3 is constantly cleaned, and in the range in which the columnar body 5 moves up and down, attachment of organisms is prevented,
Or it will be reduced. Since the wave force acting on the columnar body 5 is hardly transmitted to the column 3, it does not affect the hydrodynamic performance of the structure.

It is to be noted that organisms are apt to attach to underwater structures,
The adherent biological layer that affects the structure is formed about 1 m below the water surface and about 50 cm above the water surface. Since the maximum vertical amount of the wavefront is close to twice the wave height, for example, if the wave height of the wave in the structure installation sea area is about 1 m, it is sufficient to dispose the columnar body 5. When cleaning to a deeper position or where the wave height is small, as shown in FIG.
In addition, by suspending the columnar body 10 having no buoyancy, the cleaning range can be expanded.

In the above example, since the columnar bodies 5 and 10 are configured to roll on the surface of the column 3, the columnar bodies 5 and 10 are arranged.
The organism is prevented from adhering to itself. It should be noted that, since no fouling is observed on the rubber fender or the surface of the ship that comes into contact with the fender in a ship, there is frequent fouling, friction and rubber surfaces. It is known to be difficult. Therefore, if the columnar bodies 5 and 10 are made of such a rubber material, it is possible to use a structure in which the columnar bodies 5 and 10 are slid without rotating.

The columnar bodies 5, 10 are annularly connected by the connecting members 7, 12 and are arranged so as to cover the outer peripheral surface of the column 3, but the cross section of the column 3 is arranged so as to contact the column surface more largely. It is divided into appropriate widths according to the shape.

[0020]

INDUSTRIAL APPLICABILITY The present invention, in an offshore structure having a column, is brought into contact with the outer peripheral surface of the column and connected by a connecting member,
Since the columnar body having buoyancy is arranged and moved vertically along the column surface by the wave, it is possible to prevent organisms from adhering to the column with a simple device.
Also, the sustainability of the effect can be expected. As a result, the columns were maintained and the marine structures could be used for a long period of time.

Further, since the wave of the sea area is used for the vertical movement of the columnar body, a separate drive source is not required, and its attachment is easy, and it can be easily applied to the existing structure.
Further, by suspending the columnar body having no buoyancy from the side of the columnar body having the column, it is possible to deeply form a zone where organisms do not adhere.

[Brief description of drawings]

FIG. 1 is a schematic side view of a column provided with a column maintenance device according to the present invention.

FIG. 2 is a sectional view of the same.

FIG. 3 is a view showing a swing state of a column maintenance device.

FIG. 4 is a cross-sectional view of a columnar body.

FIG. 5 is a vertical sectional view of the same.

FIG. 6 is a diagram showing an example including a columnar body having no buoyancy.

FIG. 7 is a view showing an example in which a connecting member is provided with a spring.

FIG. 8 is a schematic view of an offshore structure targeted by the present invention.

[Explanation of symbols]

1 Offshore Structure 2 Lower Hull 3 Column 4 Upper Platform 5 Columnar Body 6 Air Chamber 7 Connecting Material 8 Spring 9 Bearing 10 Columnar Body 11 Vertical Connecting Material 12 Connecting Material

Claims (4)

[Claims] 1. A columnar body having a buoyant force, which is divided into a large number of pieces and comes into contact with the peripheral surface of a column, is annularly connected by a connecting material having an elastic force, and is arranged on the outer periphery of the column. A column maintenance device for offshore structures, wherein the column is moved up and down along the column. 2. The column maintenance in a marine structure according to claim 1, wherein the columnar body is formed into a roller shape, and the columnar body is connected to the columnar outer surface by a connecting member via a rotary bearing so as to be rolled. apparatus. 3. The column maintenance device for a marine structure according to claim 1, wherein the columnar body is made of rubber and slid on the outer peripheral surface of the column. 4. A columnar body having no buoyancy is annularly connected by a connecting member having an elastic force, and is arranged on the outer periphery of the column, and is hung on the columnar body side having buoyancy through an upper and lower connecting member. The column maintenance device for a marine structure according to claim 1, wherein: