JP4650527B2 - Movable breakwater and operating method of movable breakwater - Google Patents

Description

  The present invention relates to a movable breakwater that can be moved up and down.

Patent Document 1 includes a plurality of sheathed steel pipes that are inserted vertically into the seabed ground through the foundation concrete provided on the bottom of the sea, and arranged with the upper end face open on the surface of the foundation concrete in a dense state, Disclosed is a movable breakwater that includes a floating steel pipe that is inserted into a sheath steel pipe so as to be able to move up and down, has a lower end surface that is open, and has an upper end surface that is closed, and an air supply device that supplies air into each floating steel pipe. ing. In this structure, the column of floating steel pipes are buried on the bottom of the sea during dredging to completely open the outside of the bay and inside the bay, and in rough weather, air is sent into each floating steel pipe by an air supply device such as a compressor. This prevents the invasion of waves into the bay by projecting the column of floating steel pipes above the sea level.
JP 2004-116131 A

  However, in the movable breakwater described in Patent Document 1, when raising the levitation steel pipe, air must be supplied to all the levitation steel pipes, so a large amount of air is supplied within a short time. There is a need. Therefore, a large-sized air supply device or a large number of air supply devices must be used, and there is a problem that the capital investment cost is high.

  In addition, since each supply pipe for supplying air to each levitation steel pipe is required, if the length of the movable breakwater extension is increased and the number of levitation steel pipes is increased, the number of work for laying the supply pipe increases and the work days become longer. There was a problem.

  Furthermore, if a supply pipe with a large diameter is used to increase the amount of air in order to raise and lower the levitation steel pipe within a predetermined time, it is difficult to handle, so there is a burden on the diver who performs the installation work in the levitation steel pipe. There was a problem of being big.

  Then, this invention is made | formed in view of said problem, The objective can reduce the equipment cost of the air supply apparatus which supplies the air for raising the steel pipe for levitation, and supplies It provides a movable breakwater that requires less air.

  In order to achieve the above object, the movable breakwater according to the present invention includes a plurality of sheaths that are vertically inserted into the seabed through the foundation concrete provided on the seafloor, and are linearly arranged with the upper end face open in the sea. A steel pipe, a cylindrical levitation main pipe inserted into the predetermined sheathed steel pipe so as to be movable up and down, and closed at the top, and inserted into a sheathed steel pipe other than the predetermined sheathed steel pipe so as to be movable up and down, and air is sealed A cylindrical floating sub-tube having a sub-pipe air chamber, an air supply device for supplying air into the levitation main pipe, and the levitation main pipe and the levitation sub-pipe The levitation main pipe is lifted by the buoyancy generated by the supply air into the levitation main pipe, and the levitation sub-pipe is lifted via the connection means. Constructed to project the pipe and the levitation sub-pipe above the sea surface It is characterized in that is (the first invention).

According to the movable breakwater according to the present invention, when the levitation main pipe is raised by supplying air to the levitation main pipe, the levitation sub pipe can also be raised through the connecting means. That is, since it is sufficient to supply air only to the levitation main pipe, the number of supply pipes and the like for supplying air can be reduced. Accordingly, since the amount of work for laying supply pipes and the like is reduced, the burden on divers and workers is reduced and the number of work days is also shortened.
Further, when the levitation main pipe is lowered, the levitation sub pipe can be lowered accordingly.

According to a second aspect, in the first aspect, the sub-pipe air chamber is provided at a position where the upper end of the sub-pipe air chamber is always lower than the lowest seawater level regardless of the lift position of the levitation sub-pipe. It is characterized by being able to.
According to the movable breakwater according to the present invention, the upper end of the secondary pipe air chamber is always provided at a position lower than the lowest water level of the seawater regardless of the ascending / descending position of the floating secondary pipe. It always exists below the sea level. If the air chamber protrudes above the water surface, the air capacity in the air chamber above the water surface does not act as buoyancy, but the sub-pipe air chamber does not move even when the levitation sub-tube protrudes most from the sea surface. Since it exists at a position lower than the sea level, the buoyancy by the sub-pipe air chamber always acts on the levitation sub-pipe.

According to a third aspect, in the second aspect, the sub pipe air chamber is provided below an upper end of the levitation sub pipe, and the levitation sub pipe is disposed above the sub pipe air chamber. A hole for draining seawater flowing from the upper end of the levitation sub-pipe is provided on a side surface of the sub-pipe for use.
According to the movable breakwater according to the present invention, the levitation sub-pipe has a hole above the sub-pipe air chamber provided below the upper end of the levitation sub-pipe and on the side surface of the levitation sub-pipe. Therefore, when the levitation sub-pipe descends, the seawater can flow into the levitation sub-pipe from the hole. Further, when the levitation sub-pipe rises and the upper part of the levitation sub-pipe protrudes from the sea surface, the sea water in the levitation sub-pipe can be discharged from the hole to the outside.

A fourth invention is characterized in that, in any one of the first to third inventions, the levitation sub-pipe is movably connected to the levitation main pipe by the connecting means.
According to the movable breakwater according to the present invention, the levitation sub-pipe is movably connected to the connecting means, so that it is not necessary to accurately position the levitation sub-pipe and the sheath steel pipe during ascent and descent. It becomes possible to raise and lower the auxiliary secondary pipe smoothly with respect to the sheath steel pipe.

According to a fifth invention, in the first or fourth invention, the connecting means is fixed to an upper end of the levitation main pipe and extends to above the levitation sub pipe, and one end of the connection means The other end of the connecting member is connected to the levitation sub-pipe, and is composed of a hanger such as a wire rope for suspending the levitation sub-pipe.
According to the movable breakwater according to the present invention, the connection means for connecting the levitation main pipe and the levitation sub-pipe is composed of a connecting member and a lifting tool, and is dedicated for raising and lowering the levitation sub-pipe. Since a drive system and a control system for controlling elevation are not provided, it can be constructed at low cost.
In addition, the levitation sub-pipe is suspended from the connecting member by a lifting tool and is freely movable with respect to the levitation main pipe, so that the levitation sub-pipe and the sheath steel pipe can be prevented from being galled during ascent and descent. .

  According to a sixth aspect of the present invention, there is provided a movable breakwater operating method comprising: a plurality of sheathed steel pipes that are vertically inserted into the seabed through the foundation concrete provided on the bottom of the sea, and are arranged in a straight line with the upper end open in the sea. , Inserted into the predetermined sheathed steel pipe so as to be able to be raised and lowered, and inserted into the tubular steel pipe other than the predetermined sheathed steel pipe so as to be raised and lowered, and sealed with air. A cylindrical levitation sub pipe having a sub pipe air chamber, an air supply device for supplying air into the levitation main pipe, and a connection for connecting the levitation main pipe and the levitation sub pipe In the operating method of the movable breakwater provided with the means, the levitation main pipe is lifted by the buoyancy generated by the supply of air into the levitation main pipe, and the levitation sub-pipe is lifted via the connecting means The levitation main pipe and the levitation sub pipe on the sea surface. Characterized in that to protrude.

  According to a seventh aspect, in the sixth aspect, the air in the levitation main pipe is discharged to reduce the buoyancy of the levitation main pipe, and the levitation sub pipe is utilized by utilizing the weight of the levitation sub pipe. The levitation sub-pipe and the levitation main pipe are stored in the sheath steel pipe.

  By using the movable breakwater according to the present invention, it is possible to reduce the equipment cost of an air supply device that supplies air for raising the levitation steel pipe, and to construct a movable breakwater that requires less air to be supplied. It becomes possible.

  Hereinafter, preferred embodiments of the movable breakwater according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a plan view of a movable breakwater 1 according to an embodiment of the present invention. 2 and 3 are a cross-sectional view taken along the line AA and a cross-sectional view taken along the line BB in FIG. 1, respectively.
As shown in FIG. 1 to FIG. 3, a foundation concrete 2 having a predetermined thickness with the sea bottom GL as the top end is placed in the seabed ground E of the movable breakwater 1 that partitions the inside and outside of the port, and the root is surrounded by the root. Solid stone 3 is laid. A sheath steel pipe 4 that penetrates the foundation concrete 2 vertically and reaches the deep part of the seabed ground E is embedded in a straight line. The lower end surface of each sheathed steel pipe 4 is closed by underwater concrete 5 and the upper end face is opened upward from the foundation concrete 2, and the main pipe for levitation 6 is removed from the prescribed sheathed steel pipe 4 except for the prescribed sheathed steel pipe. The levitation sub-tube 11 is inserted into the sheath steel tube 4 so as to be movable up and down. In the present embodiment, for example, a single levitation main pipe 6 and a levitation sub pipe 11 arranged on both sides thereof are taken as a set, and the levitation main pipe 6 is disposed on both sides of the central sheath steel pipe 4. The levitation sub-pipe 11 is inserted into the sheath steel pipe 4.

  Further, an air supply device 14 for supplying compressed air to the levitation main pipe 6, a levitation supply pipe 13 for supplying the compressed air into the levitation main pipe 6, and an on-off valve 8 (described later). And an on-off valve supply pipe 12 for supplying the compressed air.

  FIG. 4 is a longitudinal sectional view of the levitation main pipe 6 according to the present embodiment. As shown in FIG. 4, the levitation main pipe 6 has a main air chamber 6b in which air is sealed at the upper end. Further, the lower end surface of the levitation main pipe 6 is opened.

  The main air chamber 6b is constructed by joining the partition walls 9a and 9b to the inner peripheral surface of the levitation main pipe 6 by welding or the like over the entire circumference, and is sealed so that seawater does not flow in. In the present embodiment, the upper end of the main air chamber 6b is provided so as to close the upper end surface of the levitation main pipe 6 with the partition wall 9a. Further, the lower end of the main air chamber 6b is provided at a position that is always lower than the lowest water level LWL of the sea level even when the levitation main pipe 6 moves up and down.

  In the present embodiment, the lower end of the main air chamber 6b is always provided at a position lower than the lowest water level LWL of the sea surface. However, the present invention is not limited to this position. It is determined by design based on conditions such as the specifications of the air supply device 14 and the time allowed for the rising of the levitation main pipe 6.

  An open / close valve 8 is provided in the main air chamber 6b to discharge the air in the levitation main pipe 6 to the outside of the levitation main pipe 6 by opening the valve. The on-off valve 8 is an air-driven valve that opens and closes with air pressure generated by compressed air.

  The lower port 8a of the on-off valve 8 in the figure is connected to a pipe 10a that passes through the partition wall 9b and communicates with the levitation main pipe 6, and the upper port 8b in the figure passes through the partition wall 9a. A pipe 10b communicating with the outside is connected. Accordingly, when the on-off valve 8 is opened, the inside of the levitation main pipe 6 communicates with the outside, and air can enter and exit. On the other hand, when the on-off valve 8 is closed, the inside of the levitation main pipe 6 communicates with the outside. The

  FIG. 5 is a longitudinal sectional view of the levitation sub-pipe 11 according to the present embodiment. As shown in FIG. 5, the lower end surface and upper end surface of the levitation sub-pipe 11 are opened. The levitation sub-pipe 11 includes a sub-pipe air chamber 11b in which air is sealed slightly above the center, an opening 11c through which seawater can enter and exit above the sub-pipe air chamber 11b, and a sub-pipe air chamber. An opening 11e through which seawater can enter and exit is provided below 11b.

  The sub-pipe air chamber 11b is constructed by joining partition walls 9c and 9d to the inner peripheral surface of the levitation sub-pipe 11 by welding or the like over the entire circumference, and is sealed so that seawater does not flow in.

  The sub-pipe air chamber 11b is provided at a position where the upper end of the sub-pipe air chamber 11b is always lower than the lowest water level LWL of the seawater even when the levitation sub-pipe 11 moves up and down. Therefore, even when the levitation sub-pipe 11 rises most and protrudes to the sea surface, the buoyancy always acts on the levitation sub-pipe 11 because the sub-pipe air chamber 11b is located in the sea. The buoyancy is set such that the pressure, volume, and the like in the sub-pipe air chamber 11b are such that the levitation sub-pipe 11 cannot be raised naturally.

Further, a drain hole 11a for draining seawater stored in the opening 11c is provided on the side surface of the opening 11c.
Further, on the side surface of the opening 11e, a water passage hole 11d is provided for smoothly raising and lowering the levitation sub-pipe 11 by entering and exiting seawater into the opening 11e.

FIG. 6 is a perspective view showing a state in which the levitation main pipe 6 and the levitation sub pipe 11 according to the present embodiment are connected.
As shown in FIG. 6, the levitation main pipe 6 and each levitation sub-pipe 11 adjacent to the levitation main pipe 6 are connected by a connecting means 7.

  The connecting means 7 has a central portion fixed to the upper end of the levitation main pipe 6, both ends extending to the upper side of the levitation sub-pipe 11, and one end at the end of the linking material 7 a, The other end is connected to the partition wall 9c of the levitation sub-pipe 11 and is composed of a lifting tool 7b such as a wire rope that suspends the levitation sub-pipe 11. The levitation sub-pipe 11 is connected to the levitation main pipe 6. It is free to move. Since the levitation main pipe 6 and the levitation sub-pipe 11 are connected by the connecting means 7, when the levitation main pipe 6 is moved up and down, the levitation sub-pipe 11 moves up and down together with the levitation main pipe 6.

  In addition, in this embodiment, although plate-shaped steel materials were used as the connection material 7a, it is not limited to this, You may use steel materials of various shapes, such as H steel and round steel.

  Below, the raising / lowering method of the movable breakwater 1 is demonstrated. In the present embodiment, it is desirable that the upper end of the sub-pipe air chamber 11b is always present at a position lower than the sea level, and therefore the rising and lowering state at the lowest water level LWL at which the conditions are most severe will be described.

7-11 is a figure which shows the raising / lowering state of the movable breakwater 1 which concerns on this embodiment.
As shown in Fig. 7, when dredging, the levitation main pipe 6 and the levitation auxiliary pipe 11 are stored inside the sheath steel pipe 4 to completely open the outside of the bay and the inside of the bay so that it becomes an open water area and sails on the sea. Ships can enter and exit the bay freely.

  The levitation main pipe 6 and the levitation sub pipe 11 have buoyancy due to the main pipe air chamber 6b and buoyancy due to the sub pipe air chamber 11b. Since the total weight of the two levitation secondary pipes 11 is smaller, the levitation main pipe 6 and the levitation secondary pipe 11 are submerged in the sea and stored in the sheath steel pipe 4.

  At this time, since the upper end surface and the lower end surface of the levitation sub-pipe 11 are open, the opening 11c and the opening 11e are filled with seawater. In addition, the on-off valve 8 is always closed, and communication between the inside of the levitation main pipe 6 and the underwater is blocked.

  As shown in FIG. 8, when the state of dredging shifts to a stormy weather and the sea swell becomes strong, the air supply device 14 provided on the ground is driven to lift the compressed air through the levitation insertion tube 13. Supply into the main pipe 6. By continuously supplying the compressed air, the combined resultant of the buoyancy caused by the air stored below the main air chamber 6b, the buoyancy caused by the main air chamber 6b, and the buoyancy caused by the sub air chamber 11b is obtained. When the total weight of the levitation main pipe 6 and the two levitation sub pipes 11 becomes larger, first the levitation main pipe 6 starts to rise. Then, the levitation main pipe 6 rises, and the two levitation sub pipes 11 are lifted and raised via the connecting means 7.

  Since the total amount of air required to raise the levitation main pipe 6 and the levitation sub-pipe 11 is determined, by providing the main pipe air chamber 6b and the sub-pipe air chamber 11b in advance, the levitation main pipe 6 and When the levitation sub-pipe 11 is raised, the amount of air supplied into the levitation main pipe 6 can be reduced.

  Further, when the levitation sub-pipe 11 rises, seawater in the sea passes through the gap between the levitation sub-pipe 11 and the sheath steel pipe 4 and flows into the opening 11e from the lower end of the levitation sub-pipe 11 and passes through. By flowing into the opening 11e from the water hole 11d, the levitation sub-pipe 11 can be raised smoothly.

  As shown in FIG. 9, at the same time as the upper part of the levitation main pipe 6 and the levitation sub pipe 11 begins to protrude from the seawater surface, the seawater in the opening 11c begins to be discharged into the sea from the drain hole 11a. Accordingly, it is possible to prevent the necessity of a buoyancy that is as large as the weight of the seawater stored in the opening 11c when the levitation sub-pipe 11 is raised.

  As shown in FIG. 10, when the levitation main pipe 6 and the levitation sub pipe 11 are completely raised, the air supply device 14 is stopped, and the supply of air into the levitation main pipe 6 is stopped.

  At this time, since the upper end of the sub pipe air chamber 11b is provided at a position where the upper end is lower than the lowest water level LWL, the sub pipe air chamber 11b is located in the sea, and the levitation sub pipe 11 is completely raised. Even in this state, buoyancy is acting on the levitation sub-pipe 11, but as described above, this buoyancy is so large that the levitation sub-pipe 11 cannot naturally levitate. If it is not suspended by 6, the levitation sub-pipe 11 will be lowered. On the other hand, the buoyancy in the levitation main pipe 6 (below the sea level) has such a size that the levitation main pipe 6 protrudes from the sea surface and the two levitation sub pipes 11 are lifted. Therefore, the levitation main pipe 6 and the levitation sub pipe 11 can maintain a state of protruding to the sea surface.

  As shown in FIG. 11, when it is determined that the rough weather condition has subsided and the sea is crawling, the on-off valve 8 is opened to connect the inside of the levitation main pipe 6 to the atmosphere. Then, the air in the levitation main pipe 6 is discharged into the atmosphere, and the buoyancy due to the air stored below the main air chamber 6b is reduced and almost eliminated, and the resultant resultant force at the time of rising is the levitation main pipe 6. When the total weight of the two levitation sub-pipes 11 becomes smaller, first, the levitation sub-pipe 11 starts to descend. Then, the levitation sub-pipe 11 is lowered, and the levitation main pipe 6 is pulled downward through the connecting means 7 to be lowered.

  When the levitation sub-pipe 11 starts to descend, seawater begins to flow into the opening 11c from the drain hole 11a. And the inside of the opening part 11c is gradually filled with seawater with the descent of the sub pipe 11 for levitation. Since the seawater that has flowed into the opening 11c plays the role of ballast, the levitation main pipe 6 and the levitation sub pipe 11 descend quickly.

  Further, the seawater in the opening 11e flows from the lower end of the levitation sub-pipe 11 through the gap between the levitation sub-pipe 11 and the sheath steel pipe 4 into the sea, and also flows into the sea from the water passage hole 11d. Thus, the levitation sub-pipe 11 can be lowered smoothly.

  Thus, when the levitation main pipe 6 and the levitation auxiliary pipe 11 are completely lowered and stored in the sheath steel pipe 4 and an open water area is formed and the ship can freely enter and exit, the on-off valve 8 is closed. The communication between the ascending main pipe 6 and the sea is cut off.

  According to the movable breakwater 1 of the present embodiment described above, when the levitation main pipe 6 is raised by supplying air to the levitation main pipe 6, the levitation sub pipe 11 is also raised via the connecting means 7. It becomes possible. That is, since it is only necessary to supply air to the levitation main pipe 6, the number of levitation supply pipes 13 for supplying air can be reduced. Accordingly, since the amount of work for laying the levitation supply pipe 13 and the like is reduced, the burden on divers and workers is reduced and the number of work days is also reduced.

  The levitation main pipe 6 has a main air chamber 6b at the upper end, and a part of the air amount necessary for the rise is stored in the levitation main pipe 6 in advance. In doing so, the amount of air that has to be supplied into the levitation main pipe 6 can be reduced. Therefore, since the air supply device 14 can be reduced in size, the capital investment cost can be reduced.

  Further, since the levitation main pipe 6 and the levitation sub pipe 11 are connected by the connecting means 7, when the levitation sub pipe 11 is lowered, the levitation main pipe 6 is lowered via the connection means 7. Is possible. Further, since the connecting means 7 is a simple device, it can be constructed at a low cost.

  The levitation sub-pipe 11 is suspended from the connecting member 7a by a lifting tool 7b, and is freely movable with respect to the levitation main pipe 6. Therefore, the levitation sub-pipe 11 and the sheath steel pipe 4 are prevented from being galling. be able to. Therefore, it becomes possible to smoothly insert / remove the levitation sub-pipe 11 with respect to the sheath steel pipe 4.

  And since the upper end of the sub pipe air chamber 11b is always provided at a position lower than the lowest seawater level LWL of the seawater even when the levitation sub pipe 11 moves up and down, the sub pipe air chamber 11b is always lower than the sea level. Located in a low position. Therefore, the buoyancy by the sub-pipe air chamber 11b always acts on the levitation sub-pipe 11.

  Furthermore, since the opening part 11c is provided with the drainage hole 11a, it becomes possible to flow seawater into the opening part 11c from the drainage hole 11a when the levitation sub-pipe 11 descends. Further, when the levitation sub-pipe 11 rises and the upper part of the levitation sub-pipe 11 protrudes from the sea surface, the sea water in the opening 11c can be discharged to the outside from the drain hole 11a.

  In addition, in this embodiment, although the case where the water level was the lowest water level LWL was demonstrated, it is not limited to this, If the water level is higher than the lowest water level LWL at the time of the highest water level HWL or the time of a wave, the sea level Is always higher than the upper end of the sub-pipe air chamber 11b, so that the present invention can be applied.

  Further, in the present embodiment, the case where two levitation sub pipes 11 are connected to one levitation main pipe 6 has been described, but the present invention is not limited to this. For example, one levitation main pipe 6 One levitation sub pipe 11 may be connected to the main pipe 6 or four levitation sub pipes 11 may be connected to one levitation main pipe 6. The number of the levitation sub-pipe 11 is appropriately determined according to the buoyancy of 6.

It is a top view of the movable breakwater which concerns on embodiment of this invention. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. It is a longitudinal section of the main pipe for levitation concerning this embodiment. It is a longitudinal cross-sectional view of the levitation sub-pipe according to the present embodiment. It is a perspective view which shows the state which connected the main pipe | tube for levitation | floating which concerns on this embodiment, and the sub pipe | tube for levitation. It is a figure which shows the raising / lowering state of the movable breakwater which concerns on this embodiment. It is a figure which shows the raising / lowering state of the movable breakwater which concerns on this embodiment. It is a figure which shows the raising / lowering state of the movable breakwater which concerns on this embodiment. It is a figure which shows the raising / lowering state of the movable breakwater which concerns on this embodiment. It is a figure which shows the raising / lowering state of the movable breakwater which concerns on this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Movable breakwater 2 Foundation concrete 3 Solidifying stone 4 Sheath steel pipe 5 Underwater concrete 6 Levitation main pipe 6a End face 6b of internal steel pipe Main pipe air chamber 7 Connection means 7a Connection material 7b Lifting tool 8 Open / close valve 8a, 8b Port 9a, 9b, 9c, 9d Bulkhead 10a, 10b Pipe 11 Levitation sub-pipe 11a Drain hole 11b Sub-pipe air chamber 11c Opening part 11d Water flow hole 11e Opening part 12 Opening / closing valve supply pipe 13 Levitation supply pipe 14 Air supply device E Submarine Ground HWL Highest water level LWL Low water level GL Sea floor

Claims (7)

A plurality of sheathed steel pipes penetrating through the foundation concrete provided on the bottom of the sea and vertically inserted into the bottom of the sea, with the upper end surface opened in the sea and linearly arranged;
A cylindrical levitation main pipe inserted into the predetermined sheathed steel pipe so as to be movable up and down and closed at the top,
A cylindrical levitation sub-tube having a sub-tube air chamber that is inserted so as to be movable up and down in a sheath steel tube other than the predetermined sheath steel tube and sealed with air,
An air supply device for supplying air into the levitation main pipe;
A connecting means for connecting the levitation main pipe and the levitation sub pipe;
The levitation main pipe is lifted by the buoyancy generated by the supply of air into the levitation main pipe, and the levitation sub pipe is lifted via the connecting means. The levitation main pipe and the levitation sub pipe A movable breakwater that is configured to protrude from the sea surface.   The said secondary pipe air chamber is provided in the position where the upper end of the said secondary pipe air chamber is always lower than the minimum water level of seawater irrespective of the raising / lowering position of the said floating secondary pipe. Movable breakwater. The secondary pipe air chamber is provided below the upper end of the floating secondary pipe,
The levitation sub-pipe includes a hole for draining seawater flowing in from the upper end of the levitation sub-pipe on a side surface of the levitation sub-pipe above the sub-pipe air chamber. The movable breakwater according to 2.   The movable breakwater according to any one of claims 1 to 3, wherein the levitation subpipe is movably connected to the levitation main pipe by the connecting means. The connecting means includes
A connecting member fixed to an upper end of the levitation main pipe and extending to above the levitation sub pipe;
The one end is connected to the connecting member, and the other end is connected to the levitation sub-pipe, and is composed of a hanging tool such as a wire rope for suspending the levitation sub-pipe. The movable breakwater described. Inserted vertically into the seabed ground through the foundation concrete provided on the bottom of the sea, inserted into the seabed with a plurality of sheathed steel pipes arranged in a straight line with the upper end open, and inserted into the predetermined sheathed steel pipes so that it can be moved up and down. A cylindrical levitation main pipe having an air chamber for a secondary pipe that is inserted in a steel pipe other than the predetermined sheath steel pipe so as to be movable up and down and sealed with air. And an air supply device for supplying air into the levitation main pipe, and a movable breakwater operating method comprising a connection means for connecting the levitation main pipe and the levitation sub pipe,
The levitation main pipe is lifted by the buoyancy generated by the supply of air into the levitation main pipe, and the levitation sub pipe is lifted via the connecting means. The levitation main pipe and the levitation sub pipe A method of operating a movable breakwater, characterized by projecting water on the sea surface.   The levitation main pipe is exhausted to lower the buoyancy of the levitation main pipe and lower the levitation sub pipe using the weight of the levitation sub pipe, and the levitation sub pipe and the levitation main pipe The actuating method of the movable breakwater according to claim 6, wherein the levitation main pipe is stored in the sheath steel pipe.

Images