JPH1181353A - Construction underwater multi-layer structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To unify joint sections of blocks by connecting them while ensuring cut-off efficiency in such a state as hollow precast blocks are sank to the bottom of the sea. SOLUTION: The multi-layer structure includes cut-off gaskets 4 and 5 on the circumferential edges of both up and down joint sections and, at the same time, in the gaskets 4 and 5, it includes processing works for immersing a lower hollow precast block 2 on a mound formed in the water by making use of a plurality of hollow precast blocks 2 and 3 arranging a large number of joint members 6 projecting toward the opposite sides each other by passing through vertically inside the gaskets 4 and 5 to fix. In the same way, it is constituted of a process for adhering the gaskets 4 and 5 to each other by positioning and fixing an upper precast block 3 to the upper part of the lower hollow precast block 2 with immersion work, a process for draining water out into a space surrounded by top slab 7 and bottom slab 8 of the hollow precast blocks 2 and 3 and gaskets 4 and 5 and a process for connecting the opposite ends of the joint members in a drained space through couplers 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for constructing an underwater multilayer structure using a block joining method.

[0002]

2. Description of the Related Art A wide variety of marine facilities used for marine development, such as fisheries, industry, residential and resource development, and park facilities, have been proposed. There are underwater structures that can be used by people. Since this underwater structure constitutes a space that can be immersed in the sea against large water pressure, it is necessary to be a structure that is robust against water pressure and has a sufficient waterproof property.

[0003] As one of the methods for constructing a large multilayer structure in the sea while satisfying the above requirements, a plurality of hollow precast blocks are sequentially joined and integrated to secure a waterproof property at a joint portion, and a large-sized precast block is secured. A block joining method as a structure has been proposed.

In this method, conventionally, one layer of hollow precast block previously constructed on land or on a floating dock is towed to the sunk position, and the next layer block is laminated while floating on the sea to stop the joint. After securing water, water is poured into the lower block to reduce buoyancy, and the next block is stacked on the top of the next block located on the sea surface, and is successively sunk while joining, and finally submerged in advance on the seabed This is a method of landing on the constructed mound.

[0005] Then, after the block is anchored, the block is anchored on the mound, the water inside the block is drained, and the partition between the blocks is removed, so that the inside of the block can be used or a large space that can be used by people. I do.

In this construction method, even if each block is large enough to be towed, it can be finally made into one structure, so that it is possible to construct a large space underwater structure. Become.

[0007]

However, in this construction method, since the work of joining each block and the work of stopping water at the joint portion are performed at sea, troublesome underwater work due to diving can be avoided as much as possible, but the weight is heavy. Blocks must be lifted and stacked in the air, requiring a dedicated work boat equipped with large heavy equipment.

Also, it is good when the sea is calm,
If there are swells, the suspended or floating blocks will wander, making mutual positioning and joining difficult.The work will be affected by weather conditions such as typhoons, and the construction period will be long, including waiting for weather recovery. There were drawbacks such as becoming

An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to integrate blocks by connecting the joints of the blocks while securing the water tightness in a state where the blocks are laid on the seabed. It is intended to provide a method for constructing an underwater multilayer structure according to the present invention.

[0010]

In order to achieve the above object, the present invention provides a gasket for stopping water at the periphery of the upper and lower joints, and a gasket inside the gasket, which penetrates the upper and lower portions thereof, and Using a plurality of hollow precast blocks where a large number of connecting members protruding toward the other side are arranged,
A step of lowering and lowering the lower hollow precast block on the mound formed in the water, and positioning and lowering the upper precast block on the upper part of the lower hollow precast block by the same laying operation, thereby bringing the gaskets into close contact with each other. A step of draining a space surrounded by a top plate, a bottom plate and a gasket of each hollow precast block, and a step of joining opposing ends of the connecting member in the drained space. Things. According to this invention, the joining work between the blocks can be performed in an environment that is relatively unaffected by the weather, such as in the sea, so that the construction period is stabilized.

[0011] In the present invention, it is preferable that the precast block is a submerged box used in a submerging method.

[0012]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIGS. 1 to 3 show a construction procedure of the present invention when an underwater structure is constructed by four blocks whose upper side is exposed to the sea. First, as shown in FIG. 1A, a submarine ground E at a construction site partitioned by a plurality of buoys anchored on the sea floor and floating on the sea surface is excavated using an excavation ship. Excavated sediment is removed by a sediment carrier.

Next, as shown in (b), the crushed stone for mound formation carried by the crushed stone carrier is scattered to the excavation site by the bucket ship, and the mound 1 is constructed. When the mound 1 is constructed, a lower hollow precast block (hereinafter, referred to as a lower block) 2 made on land or in parallel with a floating dock, as shown in FIG. On the floating dock, or with the tugboat tow just above the construction position while holding buoyancy with a float.

If the lower block 2 itself has a sufficient buoyancy, it can be floated on the sea surface and towed directly by a tug boat.

Next, as shown in FIG. 2 (b), the lower block 2 is suspended by a crane ship and settled down while securing the position of the block 2, and is landed on the mound 1. In addition,
If the lower block 2 has sufficient buoyancy and cannot be settled as it is, ballast water is injected into the internal cavity to settle while reducing buoyancy sequentially. When the position adjustment or the correction is performed after the landing, the buoyancy can be increased or decreased by the internal pouring and drainage.

In the above work, even if there is swelling in the sea, once suspended in the sea, the block will have buoyancy, and since the work atmosphere is stable in seawater,
Position adjustment work is easy, and relatively stable hanging and installation work can be performed.

The positioning and adjustment of the landing at the time of submersion can be performed with high accuracy by the position sensor using an underwater camera, sonar, etc., and the communication between a diver and a crane operator who dive. Perform submersion work. In this case, after the lower block 2 is closely arranged in parallel on the mound 1 and the upper hollow precast block (hereinafter referred to as the upper block) 3 is placed on the lower block 2 as shown in FIG. 3 (b), the upper block 3 is first placed on the lower block 2 on one side, and then the upper block 3 is stacked on the lower block 2 on the other side. be able to.

Regardless of the procedure, the joint between the blocks 2 and 3, 2 and 2 and 3 and 3 must be kept liquid-tight, and after the joining, the blocks 2 and 3, By connecting between 2 and 2 and between 3 and 3, the four blocks are integrated to form an underwater structure submerged under the sea surface WL.

Next, a lower block 2 for maintaining liquid tightness
FIG. 4 shows a joining structure of the upper block 3 and the upper block 3. In the drawing, rubber gaskets 4 and 5 for stopping water are arranged on the upper edge of the lower block 2 and the lower edge of the lower block 3. A large number of connecting members 6 protrude toward the other side in a direction perpendicular to the plane of the drawing on the upper sides of the lower block 2 and the lower sides of the upper block 3 inside the rubber gaskets 4 and 5. Are arranged.

The top plate 7 of the lower block 2 and the top plate 7 and the bottom plate 8 of the upper block 3 are temporary members made of a steel plate or the like, and a hatch 9 for worker access can be opened and closed at the center thereof. In addition, a hatch 10 is provided on each side surface.

Then, as described above, both blocks 2, 3
In a state in which the rubber gaskets 4 and 5 are accurately positioned and laminated, the rubber gaskets 4 and 5 are overlapped with each other and adhere while deforming. In this state, the seawater filled in the space A surrounded by the gaskets 4, 5 top plate 7 and the bottom plate 8 is drained, thereby increasing the water pressure. Aqueous can be obtained. The drainage in the space A can be performed, for example, by suctioning with a vacuum pump, or by injecting and removing high-pressure air.

After draining, the worker opens the hatch 9, enters the space A, and connects the opposite ends of the connecting member 6 one after another with the coupler 11, so that the blocks 2 and 3 are integrated. Can be linked to

When each of the blocks 2 and 3 has buoyancy, that is, when sinking while injecting ballast water, the blocks 2 and 3 are temporarily fixed to the mound 1 with some kind of anchoring means, and then fixed to the upper part. The ballast water inside the block 3 is drained, and then the worker enters the inside to perform the above operation.

The adjacent blocks 2 and 3 are integrated in the same manner by drainage between gaskets and coupling by a coupler. When connecting the blocks in the horizontal direction, a connection method used in a conventional burying method may be adopted.

After the integration work is completed, the water in the lower block 2 is also drained, the book is fixed on the mound 1, the temporary top plate 7 and the bottom plate 8 are removed, and the upper and lower spaces are communicated. Then, as in the case of a general structure, if the equipment interior construction work is performed according to the purpose and application, the underwater multilayer structure is completed.

The structure can be used for various purposes, such as breakwaters, artificial islands, underwater power plants, waste disposal sites, underwater observation rooms, and the like. The scale can be freely extended in block units by the number of junctions in each direction.

FIG. 5 shows another structure of the joining structure of the blocks 2 and 3. The same parts as those described above are denoted by the same reference numerals, and only the different parts will be described using different reference numerals. In this example, the point that the top plate 20 of the lower block 2 is integrally formed by the pre-cast
The top plate 20 and the bottom plate 21 are substantially the same as those shown in FIG. 4 except that they are integrally formed by a main precast. In addition, it is the same that the hatches 9 and 10 for passage are provided in each.

In this case, one block constitutes one partition space, and can move between the partition spaces through the hatches 9 and 10.

[0030]

As is apparent from the above description, according to the method for constructing an underwater multilayer structure according to the present invention, since the positioning and joining work between the blocks are performed underwater, they are not affected by weather or sea conditions. There is no delay in the construction period because the work can be performed without any trouble.

Since the joining between the blocks is carried out in the state of being installed in the water, a large-scale underwater structure can be obtained according to the facility scale to be obtained.

[Brief description of the drawings]

FIGS. 1A and 1B are explanatory views showing a mound forming step.

FIGS. 2A and 2B are explanatory diagrams showing a block laying process.

FIGS. 3A and 3B are explanatory diagrams showing the order of arranging blocks. FIG.

FIG. 4 is a cross-sectional view showing a joint structure between a lower block and an upper block.

FIG. 5 is a sectional view showing another example of the joint structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mound 2 Lower hollow precast block 3 Upper hollow precast block 4, 5 Connecting material 11 Coupler A space

Claims (2)

[Claims] 1. A plurality of hollow precasts in which a gasket for stopping water is provided at a peripheral edge of a joint portion, and a plurality of connecting members are provided inside the gasket, penetrating vertically and projecting toward each other. Using a block, lowering and lowering the lower hollow precast block on a mound formed in water, and positioning and lowering the upper precast block on the upper portion of the lower hollow precast block by the same laying operation. Contacting each other, draining a space surrounded by a top plate, a bottom plate, and a gasket of each hollow precast block; and joining opposing ends of the connecting member in the drained space. A method for constructing an underwater multi-layered structure. 2. The method according to claim 1, wherein the precast block is a submerged box used in a submerging method.