JP2002225788A - Marine structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stable marine structure held at a generally fixed horizontal position and a vertical position to keep a good fixing property, and suppressing sway due to waves by inexpensive equipment. SOLUTION: This marine structure comprises a floating marine structure body 1, fixing legs 2 provided on the periphery of the marine structure body 1, wave absorbing floats 3 provided on the outer side of the fixing legs 2, rocking levers 5 provided on the fixing legs 2 through supporting shafts 4. Inner side ends of the rocking levers 5 and the marine structure body 1 are connected by connecting shafts 6, and outer side ends of the rocking levers 5 and the wave absorbing floats 4 are connected by connecting shafts.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a floating marine structure, for example, a marine structure such as a marine airport, a marine heliport, or a marine artificial island.

[0002]

2. Description of the Related Art In recent years, since it is difficult to secure a wide place on land, attempts have been made to effectively use the sea. As part of this, there is a plan to build offshore structures such as airports and heliports on the sea. For example, a huge floating structure (megafloat) is floated on the sea, and the megafloat is moored with a rope or a chain to be used as an airport, a heliport, or an artificial island.

[0003]

However, in the above-mentioned offshore structure, since the land and the offshore structure are moored by a rope or a chain attached with an anchor, the mooring is slackened. Therefore, the offshore structure moves in the horizontal direction due to waves, tides, and the like, and cannot stay accurately at a predetermined position on the sea. In addition, it moves vertically due to fluctuations in the water level due to ebb and flow of the tide and tsunami,
Lack of fixation.

[0004] Further, there is a possibility that the offshore structure is largely shaken up and down under the influence of waves and the like, which may hinder the arrival and departure of the aircraft. In particular, when a marine structure was installed offshore far from land, it was shaken up and down greatly by the influence of large waves, and was not suitable as an airport or heliport. Therefore, it was necessary to build an expensive rigid breakwater for extinguishing large waves further offshore where the offshore structure is to be installed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and has as its object the purpose of maintaining stable fixing at a substantially predetermined horizontal position and vertical position, low cost equipment, and stable operation with less wave shaking. It is an object of the present invention to provide an improved offshore structure.

[0006]

According to a first aspect of the present invention, there is provided a marine structure including a floating marine structure main body and a fixed structure provided on an outer periphery of the marine structure main body. A leg, a wave-absorbing float provided outside the fixed leg, and a rocking lever provided on the fixed leg via a support shaft, and an inner end of the rocking lever and a marine structure main body. The swing shaft is connected by a connecting shaft, and the outer end of the swing lever and the wave absorbing float are connected by the connecting shaft.

In this offshore structure, the offshore structure main body is connected and supported by a swinging lever of a fixed length provided on the fixed leg, so that the offshore structure is almost accurately moored at a predetermined position on the sea. In other words, the marine structure main body is not moored to a slack rope or chain, but is supported and moored to a swing lever having a predetermined length that does not expand and contract. Therefore, the offshore structure is almost exactly fixed at a predetermined position on the sea.

In this marine structure, the marine structure main body and the wave absorbing float are connected to the inner and outer ends of the swinging lever, respectively. Therefore, the fluctuation of the marine structure main body due to the wave is attenuated or absorbed, and a stable marine structure is obtained.

According to a second aspect of the present invention, in the marine structure, a distance from the support shaft to a connecting shaft connecting the outer end of the swing lever and the wave absorbing float is equal to an inner end of the swing lever from the support shaft. The distance is set to be longer than the distance to a connecting shaft connecting the and the offshore structure body.

In this offshore structure, the swing lever is provided with a distance (D) between the connecting shaft on the side where the support shaft and the wave absorbing float are connected.
However, it is set longer than the distance (C) between the connecting shafts on the side where the support shafts and the marine structure main body are connected. That is, C <
Because of the relationship of D, the fluctuation of the wave absorbing float, which fluctuates contradictoryly, is larger than the vertical fluctuation of the marine structure main body. Therefore, even if the wave absorbing float has a small volume, the damping force is increased by receiving much resistance of water, and the vertical sway of the marine structure main body due to the wave is attenuated or absorbed.

According to a third aspect of the present invention, there is provided a marine structure, wherein the connecting shaft for connecting the outer end of the swing lever and the wave absorbing float is connected for connecting the inner end of the swing lever to the body of the marine structure. A wave absorbing float provided at a position lower than the shaft and connected to the outer end of the swing lever is buried in the sea.

In this marine structure, the wave absorbing buoy buried in the sea receives the resistance and buoyancy of the water in its entirety, thereby increasing the damping effect of the fluctuation, and the vertical movement of the marine structure body quickly. Attenuated or absorbed. In addition, since the wave-absorbing float is buried in the sea, it is hardly affected by waves generated near the water surface, so the damping force of the wave-absorbing float works reliably, and the body of the offshore structure shakes. Can be avoided quickly.

The offshore structure according to claim 4 of the present invention is characterized in that the entire offshore structure main body and each of the wave absorbing floats are physically substantially balanced.

In this offshore structure, since the offshore structure body and the wave absorbing float are balanced, even if the water level changes due to the ebb and flow of the tide or a tsunami, the offshore structure body and the wave that fluctuate up and down contradictoryly. The vertical position of the marine structure main body is kept constant by the balancing action of the absorption float.

[0015] The offshore structure according to claim 5 of the present invention is characterized in that the offshore structure main body is an airplane landing port or an artificial island.

In this marine structure, if the marine structure body is used as an aircraft landing port or artificial island, the anchorage is maintained almost exactly at the predetermined horizontal and vertical positions, has good fixation, and is stable with little shaking. It can be used as a marine airport, marine heliport or marine artificial island.

[0017]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 and 2 show an embodiment of the marine structure according to the present invention, FIG. 1 is a plan view thereof, and FIG. 2 is an enlarged sectional view taken along line EE of FIG.

The marine structure 10 of the present embodiment includes a floating marine structure main body 1, a plurality of fixed legs 2 provided on the outer periphery of the marine structure main body 1, and a plurality of fixed legs 2 provided outside the fixed legs 2. And a plurality of swinging levers 5 provided on the fixed leg 2 via the support shaft 4. Each rocking lever 5 (the inner end thereof) is connected to the marine structure main body 1 via a connecting shaft 6, while each rocking lever 5 (the outer end thereof).
Is connected to each wave absorbing float 3 via a connecting shaft 7.

The marine structure main body 1 is composed of a huge floating structure (mega float), for example, a marine airport or a marine heliport, and is provided to be floated at an appropriate place on the sea (where a large space can be secured). I have. The marine structure main body 1 composed of this marine airport or marine heliport has an arbitrary planar shape and three-dimensional structure in consideration of an installation place, a use purpose, and the like. The marine structure body 1 is provided with facilities necessary for the arrival and departure of the aircraft, associated facilities, and the like.

A plurality of fixed legs 2 are installed on the outer periphery of the offshore structure body 1 at appropriate intervals. The fixed leg 2 is a bridge girder-shaped leg that supports the swing lever 5,
Is provided on the seabed B and stands up to the sea.
Each fixed leg 2 is provided with a support shaft 4, and a swing lever 5 having an intermediate portion supported by the support shaft 4 is provided so as to be able to swing in the vertical direction. The marine structure body 1 has a swinging lever 5
The wave absorbing float 3 is connected to the outer end of the swing lever 5 via a connecting shaft 7.

The oscillating lever 5 is located on the side where the support shaft 4 provided at the intermediate portion thereof approaches the marine structure main body 1, and is inclined downward from the marine structure main body 1 toward the wave absorbing float 3. It is provided to be. The wave absorbing float 3 provided at the outer end of the swing lever 5 is installed in a state buried in the sea A. That is, the wave absorbing float 3 is not affected by waves mainly generated only near the water surface.
It is buried underwater A.

In the swing lever 5, the distance (D) between the connecting shaft 7 on the side where the support shaft 4 and the wave absorbing float 3 are connected is the side where the support shaft 4 and the offshore structure main body 1 are connected. Is set to be longer than the distance (C) between the connecting shafts 6. That is, a relationship of C <D is established. For example, D is set to 2C to 10C. And the marine structure main body 1 and each wave absorption float 3 are physically balanced, and the buoyancy, load, etc. received are balanced.

When receiving a wave, the offshore structure body 1 and the wave absorbing float 3 fluctuate in opposite directions. Is attenuated or absorbed.

Further, even if the water level fluctuates due to the ebb and flow of the tide, the tsunami, etc., the offshore structure body 1 and the wave absorbing float 3 fluctuate up and down contrary to each other, and the balancing action between the offshore structure body 1 and the wave absorbing float 3 Works, and the position of the marine structure main body 1 in the vertical direction is kept substantially constant. Although not shown, in order to ensure the safety of a ship navigating in the vicinity of the offshore structure 10, the wave absorbing float 3 has a pole protruding or floating above the sea and a warning light attached to the tip, or a dangerous sea area. A float or the like indicating that there is is provided.

Next, with regard to the offshore structure of this embodiment,
The operation will be described. When the offshore structure 10 is constructed at an appropriate place on the sea, the offshore structure 10 moves in a horizontal direction as one form under the force of a wave, a tidal current, or the like. Swing lever 5 provided on 2
Moored in support. That is, the offshore structure body 1
Is supported and moored in a stuck state by a swinging lever 5 having a fixed length provided on a fixed leg 2 erected from the seabed B.

Therefore, even if the marine structure main body 1 receives a wave, a tidal current, or the like, the marine structure main body 1 is reliably moored at a predetermined position on the sea. In other words, since the marine structure main body 1 is supported and moored by the swinging lever 5 having a predetermined length that does not expand and contract, the marine structure main body 1 is almost accurately held at a predetermined position.

The marine structure main body 1 swings up and down due to waves, tides, and the like. The marine structure main body 1 has a wave absorbing float 3 connected to the outer end of a swing lever 5. That is, the wave absorbing float 3 that attenuates or absorbs the vertical sway of the offshore structure body 1 is connected. Therefore, when the marine structure main body 1 receives a wave, the wave absorbing float 3 fluctuates up and down in a direction opposite to the marine structure main body 1 to attenuate or absorb the sway of the marine structure main body 1 due to the wave. The vertical movement of the marine structure main body 1 due to the waves is eliminated.

Therefore, even when the marine structure 10 is installed offshore far from land, which is susceptible to large waves and winds, it is not necessary to provide a special breakwater for breaking off offshore. The influence of waves and wind is small. Therefore, stable offshore structures can be installed offshore at low cost.

The relationship between the length of the support shaft 2 of the swing lever 5 and the connection shafts 6 and 7 at both ends is C <D, that is, D = 2.
The relationship is C to 10C. The wave absorbing float 3 connected to the outer end of the swing lever 5 is buried in the sea A.

Therefore, when a wave is received, the up-and-down fluctuation of the wave absorbing float 3 which is opposite to the up-and-down movement of the marine structure main body 1 is larger, and the wave absorbing float 3 completely reduces the water resistance. And the damping effect increases. Therefore, the vertical sway of the marine structure main body 1 is smoothly and quickly attenuated or absorbed. In other words, the fluctuation damping action of the wave absorbing float 3 is steadily acting, and the wave of the marine structure main body 1 is eliminated early.

The marine structure body 1 and each wave absorbing float 3 as a whole are physically balanced. Therefore, even if the water level rises and falls due to the ebb and flow of the tide, the tsunami, etc., the offshore structure body 1 and the wave absorbing float 3 reciprocally attenuate the fluctuations, maintain the balance, and keep the vertical position constant. Therefore, the marine structure main body 1 is fixed without any vertical movement, and is almost the same as land. As a result, the aircraft can be smoothly departed and arrived, and the safety of operation can be improved.

3 and 4 show another embodiment of the offshore structure according to the present invention. FIG. 3 is a plan view of the offshore structure, and FIG. 4 is an enlarged sectional view taken along line FF of FIG. The offshore structure 20 according to this embodiment includes two or more offshore structure bodies 11, 1 in close proximity.
1 is provided (in this case, there are two marine structure bodies).

The offshore structure 20 includes the offshore structure body 11,
11 are connected by a connecting lever 19 (or a fixed connecting rocking lever) having connecting shafts at both ends, and fixed legs 12 are installed outside the entire offshore structure main bodies 11, 11.
A swing lever 15 is supported by a support shaft 14 provided on each fixed leg 12, and the inner end of the swing lever 15 and the offshore structure body 11
Are connected by a connection shaft 16, and the outer end of the swing lever 15 and the wave absorbing float 13 are connected by a connection shaft 17.

In the case of the offshore structure 20, the offshore structure 10 has the same operation and effect as the offshore structure 10 of the above embodiment, the offshore structure 20 is moored at a predetermined position on the sea, and the stability of the offshore structure is small. Will be high. It should be noted that if a fixed leg erected from the sea floor B is provided between the marine structure main bodies 11 and 11, and a connection swing lever provided via a support shaft fixed to the fixed leg is used for connection, It fluctuates in the opposite direction between the marine structure main bodies 11, 11, and the vibration caused by the wave is attenuated or absorbed, and the marine structure becomes a highly stable marine structure.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment. For example, mainly in the vicinity of the pivot of the swing lever,
A spring or a shock absorbing mechanism for absorbing a shock is provided at an inner end or an outer end of the swing lever. Further, in order to adjust the weight of the wave absorbing float, a structure is adopted in which a weight is attached to the wave absorbing float. The marine structure according to the present invention is most suitable for an aircraft departure / arrival port such as a marine airport and a heliport.
It is also suitable for stockpiling bases for marine oil, artificial islands, etc.

[0036]

As described in detail above, according to the present invention, the offshore structure is almost accurately moored at a predetermined position on the sea by being connected and supported by the swing lever having a fixed length. In addition, the offshore structure main body and the wave absorbing floats fluctuate in opposite directions, thereby attenuating or absorbing the sway caused by the wave, thereby providing a stable offshore structure.

If the fluctuation amount of the wave absorbing float is larger than that of the body of the offshore structure, the damping force of the vibration can be increased,
Waves of offshore structures are less swayed. Further, since the marine structure body and the wave absorbing float are physically balanced, the position in the vertical direction is kept constant, and a stable marine structure substantially similar to land is obtained.

[Brief description of the drawings]

FIG. 1 is a plan view of an embodiment of a marine structure according to the present invention.

FIG. 2 is an enlarged sectional view taken along the line EE of FIG. 1;

FIG. 3 is a plan view of another embodiment of the offshore structure according to the present invention.

FIG. 4 is an enlarged sectional view taken along line FF of FIG. 3;

[Explanation of symbols]

 10,20 Offshore structure 1,11 Offshore structure body 2,12 Fixed leg 3,13 Wave absorbing float 4,14 Supporting shaft 5,15 Swing lever 6,7,16,17 Connecting shaft A Underwater

Claims (5)

[Claims] 1. A floating offshore structure main body, a fixed leg provided on an outer periphery of the offshore structure main body, a wave absorbing float provided outside the fixed leg, and a support shaft connected to the fixed leg. A swinging lever provided on the swinging lever, the inside end of the swinging lever and the body of the offshore structure are connected by a connecting shaft, and the outside end of the swinging lever and the wave absorbing float are connected by a connecting shaft. Characteristic marine structures. 2. A distance from the support shaft to a connection shaft connecting the outer end of the swing lever and the wave absorbing float is from the support shaft to a connection shaft connecting the inner end of the swing lever and the body of the offshore structure. The marine structure according to claim 1, wherein the marine structure is set to be longer than the distance. 3. A connecting shaft connecting the outer end of the swinging lever and the wave absorbing float is provided at a lower position than a connecting shaft connecting the inner end of the swinging lever and the marine structure main body. The marine structure according to claim 1 or 2, wherein the wave absorbing float connected to the outer end of the lever is buried in the sea. 4. The offshore structure according to claim 1, wherein the offshore structure body and each of the wave absorbing floats are physically substantially balanced. 5. The marine structure main body is an aircraft landing port or an artificial island.
Or a marine structure described in 4.