JP4301104B2 - Movable breakwater, operating method of movable breakwater - Google Patents

Description

  The present invention relates to a movable breakwater that partitions, for example, the inside and outside of a harbor.

  Conventional breakwaters are composed of elongated concrete blocks that are fixedly installed on the bottom of the seabed continuously from the land on the left and right sides of the port entrance. The central part is opened as an open water area such as a channel, and both breakwaters A navigation sign tower consisting of red light and green light is placed at the top of the opposite end of the bay to guide ships entering and exiting the bay.

  In this structure, if the port is not sufficiently surrounded by natural terrain, the swells are large during stormy weather such as typhoons, and long-period waves generated in the open sea are incident from the open water area, and the calmness in the port However, there was a possibility that the ship moored in the port greatly swung due to the invasion of the waves, and the mooring line was broken or the ship itself collided with the quay.

  Moreover, as a countermeasure against stormy weather, in addition to the breakwater, there is a case where a wave breaker made of concrete blocks or the like is fixedly installed offshore in an open water area. In addition to having a poor outlook, the route was obstructed, and ships entering and leaving the port had to bypass the quake to enter and exit, which was troublesome to maneuver and had problems with the landscape.

  On the other hand, during calm periods such as dredging, there is a problem that the port is likely to become a closed water area and the water quality tends to deteriorate because it is open to only one open water area.

The present invention solves the above-mentioned problems, and its purpose is to make it possible to pass a ship by being buried on the seabed during calm weather such as dredging, and to close the port mouth by projecting to the sea during stormy weather. It is intended to provide a movable breakwater that can prevent entry into a harbor and a method for operating the same.

Multiple wherein this onset bright To achieve the object, which extends through the concrete foundation provided on the seabed is vertically inserted into the seabed, and the top surface to the surface of the concrete foundation has been arranged by an opening in a confluence A lower steel pipe, an upper steel pipe that is slidably inserted into the lower steel pipe and has a lower surface opened and closed at the top, a feed pipe embedded in the seabed and connected to the bottom of the lower steel pipe, wherein an air supply device for supplying air into the upper steel tube through Okutsukan, a movable breakwater which causes buoyancy to a predetermined height protrude the upper steel pipe on the sea surface to the upper steel tube by air, the The weight of the upper steel pipe of the portion protruding above the sea surface of the upper steel pipe is W1, the underwater weight of the upper steel pipe in seawater is W2, the inner area of the upper steel pipe is S, and the unit weight of seawater is γw Of the upper steel pipe Surface, the position is the distance H to the lower side (W1 + W2) / (γw × S) from the sea surface, provided with air vent holes having a function of discharging feed the same amount per unit of the air supply unit time it shall be the features a.

Further, the present invention is a plurality of lower steel pipes that are vertically inserted into the seabed ground through the concrete foundation provided on the bottom of the sea, and arranged with the top surface opened to the surface of the concrete foundation in a dense state, The lower steel pipe is slidably inserted, the lower surface is opened and the upper part is closed, and the upper steel pipe is provided with an air vent at a predetermined position on the side surface, and is embedded in the seabed and connected to the bottom of the lower steel pipe And a movable breakwater that projects buoyancy in the upper steel pipe by the air and causes the upper steel pipe to protrude above the sea surface. The air supply device is controlled such that the amount of protrusion of the upper steel pipe onto the sea surface is a predetermined height.

  Therefore, according to the present invention, in the case of dredging, the outer sea and the harbor are completely opened by allowing the column of the upper steel pipe to be buried in the bottom of the sea. In stormy weather, the air supply device sends air into the upper steel pipe and lifts it from the bottom of the sea by its buoyancy, thereby closing the port entrance with the steel pipe columns on the sea and preventing the incidence of waves. , Keep the harbor calm. In addition, since excess air is discharged | emitted from an opening part, it does not produce excessive buoyancy, but always stands at a fixed height on the sea surface.

  Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 3 show a plan view, a front view, and a side sectional view of a movable breakwater according to the present invention. In the figure, a foundation concrete 2 having a predetermined thickness with the bottom surface GL as the top end is placed in the center position of the existing fixed breakwater 1 that partitions the inside and outside of the port, that is, in the seabed ground E in the open water area, and around it. The foundation stone 3 is laid.

  The lower steel pipe 4 which penetrates the foundation concrete 2 vertically and reaches the deep part of the seabed ground E is densely embedded in a straight line.

  The bottom of each lower steel pipe 4 is closed by underwater concrete 5, and the upper side is opened to the surface side of the foundation concrete 2, and the upper steel pipe 6 constituting the liftable breakwater is inserted into each lower steel pipe 4 so that it can be raised and lowered. is doing.

  As shown in FIG. 1 in particular, a branch pipe 7 protrudes from one lower side portion of each lower steel pipe 4, and each branch pipe 7 is connected to a feed pipe 8 that is buried in the seabed ground. Has been.

  As shown in FIG. 3, the transmission pipe 8 communicates with an air supply device 9 provided in a management building (not shown) on the land portion side through an electromagnetic valve 10, and drive control of the air supply device 9 is performed. This is performed by the control unit 12.

  The bottom surface of the upper steel pipe 6 is opened, the top is covered, and a flange 6a is formed on the periphery of the top. An electromagnetic valve 11 communicating with the inside of the upper steel pipe 6 is provided on the top surface of the top, and the electromagnetic valve 11 is controlled to be opened and closed by remote operation from the management building.

  When the upper steel pipe is raised, air is supplied from the air supply device 9 according to an instruction from the control unit 12 and injected into the space surrounded by the upper steel pipe 6 and the lower steel pipe 4 through the transmission pipe 8, and when the lower steel pipe is lowered. In response to an instruction from the control unit 12, the electromagnetic valve 11 is opened, and the upper steel pipe 6 is lowered by discharging the air inside the upper steel pipe 6, and is stored in the lower steel pipe 4.

  Further, as shown in a cross-sectional view in FIG. 4, the inside of the upper steel pipe 6 is provided with a plurality of reinforcing ribs 14 so as to resist water pressure such as high waves.

  Further, an opening 15 for discharging excess air is opened at a predetermined position of the upper steel pipe 6 as shown in FIG. 3, and buoyancy is generated in the upper steel pipe 6 by the air supplied by driving the air supply device 9. When surplus air is projected by a predetermined length on the sea surface WL, excess air is discharged and always kept at a predetermined length.

  The upper steel pipe weight of a portion of the upper steel pipe 6 protruding a predetermined height above the sea surface WL is W1, the underwater weight of the upper steel pipe in the seawater is W2, the inner area of the upper steel pipe is S, and the unit weight of the seawater is γw. Then, the distance H from the sea level WL to the air vent hole is γw × H × S = W1 + W2 (referred to as Equation 1). When Expression 1 is modified, H = (W1 + W2) / (γw × S), and the opening position H can be determined.

  After the excess air is discharged from the opening 15, the upper steel pipe 6 is kept protruding from the sea surface WL with a predetermined length without supplying air, but the wave height varies. Accordingly, since air is discharged up and down each time, the air supply device 9 is driven and controlled so that the amount of protrusion of the upper steel pipe 6 onto the sea surface is always a predetermined length. The drive control method of the air supply device 9 may be continuously infused at all times, or may be infused at predetermined time intervals.

  2 and 3 show a state in which the wave swell is large under stormy weather, and the column of the upper steel pipe 6 protrudes to the sea. There is a slight gap between the column rows, but most of the waves collide with the column rows and the amount of waves entering the port from the gap is small, so there is some undulation in the port. It will be about.

  In addition, at the raised position of the upper steel pipe 6, the base side of the upper steel pipe 6 is positioned on the lower side of the foundation concrete 2 by a stopper (not shown) so that the bending moment due to waves is received by the portion of the foundation concrete 1. The sliding contact portions of both the steel pipes 4 and 6 are kept airtight and rustproof by a waterproof packing, a rustproof surface treatment, and the like.

  Since the buoyancy is always constant since the opening 15 is provided, the upper steel pipe 6 does not come out of the lower steel pipe 4, so that a stopper need not be provided.

  In the above, as shown in FIG. 5 (a), at the time of dredging, the solenoid valve 11 is released, and the upper steel pipe 6 is lowered by discharging the air inside the upper steel pipe 6, and is accommodated inside the lower steel pipe 4. This level is the same as that of the sea bottom GL, and this part becomes an open water area, and the ship 16 navigating the sea can freely enter and exit the harbor.

  If the swell condition shifts from this dredged state to stormy weather and the swells at sea become stronger, it can be sent to various ships such as electronic bulletin boards, ship radios, and in-port broadcasts for ships 16 that navigate or enter and leave the port. After warning that the port is to be closed and confirming that all ships owned or scheduled to enter the port have evacuated to the port, the solenoid valve 11 is closed as shown in FIG. By injecting air into the space surrounded by the upper steel pipe 6 and the lower steel pipe 4 through the transmission pipe 8, the upper steel pipe 6 gains buoyancy and rises to the sea as shown in (c) and FIGS. Receiving waves that stand upright, this keeps the harbor calm.

  In addition, abnormal high tide levels may occur in typhoons and the like, and in normal fixed breakwater 1 there is a risk that high waves will pass over breakwater 1 and floods occur. Since the upper steel pipe 6 is always located on the sea at a predetermined height, the risk of flooding associated with an abnormally high tide level can be avoided.

  If it is judged that the sea is red again from the stormy weather condition, an alarm is issued to open the port again, and then the solenoid valve 11 is released as shown in (d), and the air inside the upper steel pipe 6 is released. The column of the upper steel pipe 6 loses buoyancy and is lowered and stored in the lower steel pipe 4. Thereby, as shown to (a) again, an open water area is formed and the ship 16 will be in the state which can enter / exit freely.

  As shown in the embodiment, the above movable breakwater is located between the existing fixed breakwaters 1 and placed on the bottom of the sea that will be the open water area, so that all open water areas can be shut off during stormy weather. Alternatively, it can be placed on the sea floor offshore in the open water area of the existing breakwater 1. Furthermore, if it is desired to secure a sufficient area for the port at the time of dredging, it is possible to configure the whole with a movable breakwater.

It is a top view of the movable breakwater according to the present invention. It is the same front view. FIG. FIG. 4 is a sectional view taken along line AA in FIG. 3. (A)-(d) is explanatory drawing which shows the raising / lowering state of the breakwater.

Explanation of symbols

1 Breakwater 2 Foundation concrete 3 Root stone 4 Lower steel pipe 5 Underwater concrete 6 Upper steel pipe (movable breakwater)
7 Branch pipe 8 Transport pipe 9 Air supply device 10, 11 Solenoid valve 12 Control part 14 Reinforcement rib 15 Opening part 16 Ship E Submarine ground WL Sea surface GL Sea bottom

Claims (2)

A plurality of lower steel pipes penetrating vertically through the concrete foundation provided on the bottom of the sea and vertically inserted into the bottom of the seabed, and arranged in a dense state with the top surface opened on the surface of the concrete foundation;
An upper steel pipe that is slidably inserted into the lower steel pipe, and whose lower surface is open and whose upper part is closed;
A transmission pipe embedded in the seabed and connected to the bottom of the lower steel pipe;
An air supply device for supplying air into the upper steel pipe through the transmission pipe, and a movable breakwater that causes the upper steel pipe to protrude a predetermined height above the sea surface by generating buoyancy in the upper steel pipe by air,
The weight of the upper steel pipe of the portion protruding above the sea surface of the upper steel pipe is W1, the underwater weight of the upper steel pipe in the seawater is W2, the inner area of the upper steel pipe is S, and the unit weight of the seawater is γw As a discharge function of the same amount as the supply amount per unit time of the air supply device at a position where the distance H from the sea surface to the lower side of the side surface of the upper steel pipe is (W1 + W2) / (γw × S) A movable breakwater provided with an air vent hole. A plurality of lower steel pipes penetrating vertically through the concrete foundation provided on the bottom of the sea and vertically inserted into the bottom of the seabed, and arranged in a dense state with the top surface opened on the surface of the concrete foundation;
An upper steel pipe that is slidably inserted into the lower steel pipe, has a lower surface opened and an upper part closed, and an air vent hole is provided at a predetermined position on the side surface;
A transmission pipe embedded in the seabed and connected to the bottom of the lower steel pipe;
An air supply device for supplying air into the upper steel pipe through the feed pipe, and a method of operating a movable breakwater in which buoyancy is generated in the upper steel pipe by air and the upper steel pipe is projected on the sea surface,
A method for operating a movable breakwater, wherein the air supply device is controlled so that a protruding amount of the upper steel pipe onto the sea surface has a predetermined height.

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