JPH1121867A - Artificial land, constructing method of artificial land, and extending method of artificial land - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suitably dispose burned ashes of refuse and industrial waste by connecting a plurality of caissons annularly in plan view to constitute an annular caisson frame, and setting it on a water bottom in the state where the upper surface of the frame body is protruded from a water level. SOLUTION: A number of caissons 2 are assembled in a square to constitute a caisson frame 3 by reinforced concrete so as to have a hollow rectangular parallelopiped inner space. The frame 3 is set on a water bottom so that the upper surface is protruded from a water level S, and the water bottom is set larger than the frame 3 in a plan view to form a batholis 5 for the frame 3 on the improved ground. At that time, a recessed part substantially equal to the size in plan view of the frame 3 is formed on the ground, bentonite concrete is placed therein to form the batholis 5 having satisfactory deformation following property and high water shielding property. The frame body 3 is set on the batholis 5, a waterproof layer is formed between the batholis 5 and the inside surface of the frame 3, a waterproof sheet is laid on the batholis 5, and the edge part of the waterproof sheet is fixed to the upper surface of the frame 3. Thus, the inside of the frame 3 can be used as disposing place of burned ashes of refuses.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to
For example, the present invention relates to an artificial island used as a garbage disposal site, a method of constructing an artificial island, and a method of expanding an artificial island.

[0002]

2. Description of the Related Art In recent years, population concentration in urban areas and improvement in living standards have led to an increase in the production of consumer goods and diversification of products, resulting in a large amount of various and various garbage being discharged from daily life of urban residents. And, on the other hand, every industry has produced a lot of garbage with its activities. Generally, such refuse is incinerated at land-based refuse treatment facilities and landfilled. On the other hand, in large metropolitan areas, the amount of garbage is becoming more and more intense, and existing garbage disposal facilities cannot keep up with the amount of garbage generated, and some of the generated garbage is incinerated. In fact, they are dumped in a predetermined place without doing so.

[0003]

Therefore, a new garbage disposal facility is being planned for construction. However, even if a new garbage disposal facility is constructed, a large amount of garbage is generated.
While a large amount of incinerated ash is generated, the number of places where the incinerated ash is buried is decreasing year by year, so it cannot be a drastic solution to the waste disposal problem. Also, construction surplus soil and industrial waste
Although dumping is performed at a predetermined location, the capacity at the dumping site is also reaching its limit, and it is a fact that it is difficult to select a new dumping site especially in a metropolitan area.

The present invention has been made in view of the above circumstances, and is an artificial island suitable for dumping incineration ash of garbage, construction soil, industrial waste, and the like, and this artificial island is easily placed on the sea or the like. It is an object of the present invention to provide a method for constructing an artificial island and a method for expanding an artificial island that can be constructed in a country.

[0005]

In order to achieve the above object, the artificial island according to the first aspect of the present invention forms an annular caisson frame by connecting a plurality of caissons in an annular shape in plan view. The caisson frame is installed on the water floor with its upper surface protruding from the water surface.

The caisson is made of, for example, reinforced concrete, and its shape is preferably a rectangular parallelepiped hollow inside. However, the shape is not limited to a rectangular parallelepiped if the inside is hollow. Shape, polygonal shape in plan view,
Any shape such as an arc shape in a plan view and an L-shape in a plan view may be used.Furthermore, the sizes and shapes of the plurality of caissons constituting the caisson frame may be all the same, or the sizes and shapes may be appropriately adjusted. May be changed.

The caisson frame carries a plurality of caissons to a place where an artificial island is to be constructed, or floats a barge at a place where an artificial island is to be constructed, and manufactures a caisson on the barge. The caisson frame may be formed by installing and connecting these caissons on the water floor, or a caisson frame may be formed by connecting a plurality of caissons in advance, and the caisson frame may be transported to a place where an artificial island is to be constructed. It may be installed. When the caisson is installed, water (seawater) is injected into the caisson to settle the caisson. In addition, a pump with a purification device was installed in this caisson frame, and when incinerated garbage, construction soil, industrial waste, etc. were dumped inside the caisson frame, the water inside the caisson frame increased. Minutes are extracted by the pump with the purifying device and discharged to the outside (outside sea).

In the artificial island according to the first aspect, the caisson frame is installed on the bottom of the water with its upper surface protruding from the surface of the water, so that the inside of the caisson frame is incinerated ash of garbage, construction residue, and industrial waste. It becomes a suitable place for dumping.

[0009] The artificial island of claim 2 is based on claim 1,
A waterproof layer is formed on the water bottom located at the bottom inside the caisson frame and on the inner peripheral surface of the caisson frame.

In order to form the waterproof layer, for example, a waterproof sheet may be laid on the water bottom inside the caisson frame, and the edge of the waterproof sheet may be raised up to the upper surface of the caisson frame. . Then, the edge of the waterproof sheet raised up to the upper surface of the caisson frame is fixed to the upper surface of the caisson frame. When laying the waterproof sheet, it is preferable that the caisson frame be filled with water (seawater) so that the caisson frame can withstand the water pressure outside the caisson frame.

In the artificial island according to the second aspect, the waterproof layer is formed on the water bottom located on the inner bottom of the caisson frame and the inner peripheral surface of the caisson frame in the first aspect.
Water (seawater) outside the caisson frame does not enter the inside of the caisson frame, and does not leak from the inside of the caisson frame to the outside. Therefore, the inside of the caisson frame is a more suitable place for dumping incineration ash of garbage, construction residue, industrial waste, and the like.

According to a third aspect of the present invention, there is provided a method of constructing an artificial island, wherein a caisson is manufactured on a barge, and after the caisson manufacturing step, the caisson is lowered from the barge by sinking the barge. A caisson floating step of floating on the water in a separated state, after this caisson floating step, a barge moving step of horizontally moving the barge away from the caisson by horizontally moving the barge, and after this barge moving step, By sinking the caisson, a caisson installation step of installing the caisson on the water floor with its upper part protruding from the water surface, and after the barge moving step, a barge floating step of floating the barge, By repeatedly performing a predetermined number of times, a plurality of caisson is installed in an annular shape to form an annular caisson frame, and when the caisson is installed on the water bottom in the caisson installation step, this caisson is used. It is characterized by connecting in to another caisson placed on the sea bed prior to the same.

[0013] For example, a thin self-propelled barge is used as the barge, and water is injected into the barge to sink the barge, while water is extracted from the barge. The barge is raised. Further, the caisson is, for example, made of reinforced concrete and preferably has a hollow rectangular parallelepiped shape as in the case of claim 1, but the shape is not limited to a rectangular parallelepiped shape. ,
Further, the sizes and shapes of the plurality of caissons constituting the caisson frame may be all the same, or the sizes and shapes may be appropriately changed.

A hole is formed in a predetermined position in the caisson so that a plug can be detachably attached to the hole. And in the state where the hole was plugged,
The caisson floats on the water (sea), while the plug is removed and water is injected into the caisson so that the caisson sinks. The caisson is provided with a valve instead of forming a hole, and by opening and closing this valve,
Water may be taken in and out of the caisson.

The annular caisson frame is usually formed in a square ring, but is not limited to this, and may be formed in a polygonal ring or an annular ring. Further, when the caisson is installed on the bottom of the water in the caisson installation step, the caisson to be installed is attracted to the existing caisson previously installed by using a wire from the existing caisson, thereby forming the existing caisson. A caisson to be installed at the abutment. For this connection, for example, a connection technique between segments used in a shield method may be applied.

In the method for constructing an artificial island according to claim 3,
The caisson manufacturing step, the caisson floating step, the barge moving step, the caisson setting step, and the barge floating step are sequentially repeated a predetermined number of times, and when the caisson is set on the water bottom in the caisson setting step, By connecting the caisson to another caisson that was previously installed on the bottom, the annular caisson frame can be installed on the bottom with its upper part protruding from the water surface, that is, the caisson frame is artificially It can be easily constructed on the sea as an island. The inside of the caisson frame is a suitable place for dumping incineration ash of garbage, construction residual soil, industrial waste, and the like.

The method for expanding an artificial island according to claim 4 is based on claim 1.
Or an artificial island constructed by the artificial island construction method according to claim 3 or 2, wherein a part of a plurality of existing caissons constituting the caisson frame is removed. Levitating, moving the levitated caisson to a position where the caisson frame can be opened,
By re-sedimenting the caisson at this position, the caisson is relocated in the existing caisson moving and re-installing step in which the caisson is installed on the bottom of the water with its upper part protruding from the water surface, and An installation caisson, an existing caisson, and a new caisson connected to form a ring, and a new caisson connection installation step of installing the new caisson on the water bottom with its upper part protruding from the water surface. It is characterized by:

When part of the existing caisson is levitated, the water in the caisson is extracted by a pump or the like. When moving the levitated caisson, the caisson is placed on the barge by moving the barge under the caisson and levitating, or the barge is moved, or the raised caisson is moved. By towing with a tugboat or the like. In order to settle the floated caisson again, water (seawater) is injected into the caisson.

The new caisson is manufactured, for example, on a barge. Then, this barge is settled in the vicinity of the existing caisson, a new caisson is separated vertically from the barge, and then the barge is moved horizontally to separate the caisson horizontally, and then By sinking the caisson, the caisson is placed on the water floor with its upper part protruding from the water surface and connected to the existing caisson.

In the method for expanding an artificial island according to claim 4,
By repeating the existing caisson moving re-installation step and the new caisson connection installation step a predetermined number of times as necessary, the artificial island is gradually expanded without waste of the caisson. Therefore, the artificial island, that is, the place where the incinerated ash, construction waste, industrial waste, etc. should be dumped, should be expanded in accordance with the situation such as the amount of incineration ash, construction waste, industrial waste, etc., or economic conditions. Can be.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 and 2 show an example of an artificial island according to the present invention. FIG. 1 is a perspective view showing a state where an artificial island is installed on the sea, and FIG. 2 is a sectional view of the same. The artificial island 1 shown in these figures has a vertical and horizontal length of about 1 km × 1 km in plan view, and is a caisson frame formed by assembling a large number of caissons 2 in a substantially square ring shape in plan view. 3 as a main component.

The caisson 2 is made of reinforced concrete and has a hollow rectangular parallelepiped inside. The size of the caisson 2 is, for example, 100 m in length and 3 in width.
The height is about 0 m and the height is about 25 m, but is not limited to this size. The caisson frame 3 is installed on the water floor with its upper surface protruding from the water surface (sea surface) S.

When the caisson frame 3 is installed on the water bottom (sea bottom), as shown in FIG. 2, the water bottom where the caisson frame 3 is to be installed is larger than the size of the caisson frame 3 in plan view, and The ground is improved to a depth of about 5 to 15 m, and the bottom 5 of the caisson frame 3 is formed on the improved ground 4.

The bottom 5 is formed by forming a recess having a size substantially equal to the size of the caisson frame 3 in a plan view on the ground 4 and pouring bentonite concrete into the recess. The bottom plate 5 formed in this manner has good deformation followability and high water shielding. The caisson frame 3 is installed on the bottom 5, and a waterproof layer 6 is formed on the bottom 5 of the caisson frame 3 and the inner peripheral surface of the caisson frame 3. In FIG. 1, the waterproof layer 6 is omitted to show the arrangement of the caisson 2.

The waterproof layer 6 is formed by laying a waterproof sheet 6 on the bottom plate 5 and raising the edge of the waterproof sheet 6 to the upper surface of the caisson frame 3.
The edge of the waterproof sheet 6 raised up to the upper surface of the caisson frame 3 is fixed to the upper surface of the caisson frame. When the waterproof sheet 6 is laid, it is preferable that the caisson frame 3 is filled with water (seawater) so that the caisson frame 3 can withstand the water pressure outside the caisson frame 3. Also,
On the upper surface of the caisson frame 3, a pump 7 with a purifying device is provided.
Is installed. The pump 7 with the purifying device extracts the increased water in the caisson frame 6 when the incineration ash of the garbage, construction soil, industrial waste, and the like are dumped inside the caisson frame 6, and extracts the outside ( (Outside sea).

Next, an example of a method for constructing the artificial island 1 having the above configuration will be described with reference to FIG. Note that FIG.
In (a) and the like, the caisson 2 and 2 already installed on the sea floor have been installed through the same steps as those described below. Before the caisson 2 is installed, the seabed on which the caisson 2 is to be installed is ground-improved, and the bottom 5 is formed on this ground-improved ground 4.

First, as shown in FIG. 3A, the caisson 2 is manufactured on a thin self-propelled barge 10 (caisson manufacturing process). After the caisson 2 is manufactured, the winder 11 is attached to another caisson 2 already installed on the bottom of the water, and the wire 12 is unwound from the winder 11 and the wire 1 is wound.
2 is locked to the caisson 2 manufactured above.

Next, as shown in FIG. 3B, the barge 10 is settled by injecting water (seawater) into the barge 10. Then, since the inside of the caisson 2 is hollow, the caisson 2 floats on the water and separates upward from the barge 10 (caisson floating step). In addition, even if the caisson 2 floats, since the wire 12 is locked to the caisson 2, the caisson 2 does not flow by the tide, wind, or the like.

Next, as shown in FIG.
Is moved horizontally to the right in the figure to separate it horizontally from the caisson 2 (barge moving process). Then, the caisson 2 is attracted to the existing caisson 2 by winding the wire 12 by the winding machine 11, and is brought into contact with the existing caisson 2.

Next, as shown in FIG. 3D, the wire 12 is removed from the caisson 2 that has been attracted, and the caisson 2 is settled, so that the caisson 2 has its upper part protruding from the water surface. Install on the water floor (caisson installation process). To settle the caisson 2, a hole is formed at a predetermined position of the caisson 2, a plug is detachably attached to the hole, and the plug is removed and water is poured into the caisson. This causes the caisson 2 to settle.

When installing the caisson 2 on the water floor, the caisson 2 is connected to an existing caisson 2 to which the caisson 2 has been attracted. For this connection, for example, a connection technique between segments used in a shield method may be applied, but the technique is not limited to this technique. Further, while the caisson 2 is settled, water is extracted from the barge 10 and air is injected to float the barge (barge floating step). Up to this point, one process of manufacturing one caisson 2, connecting this caisson 2 to the existing caisson 2 and installing it on the seabed is completed.

After that, as shown in FIG. 3 (e), the next caisson 2 is manufactured by the floating barge 10, and further,
By repeatedly performing the steps shown in FIGS. 3B to 3E a predetermined number of times sequentially, a large number of caisson 2... Are installed in a ring, thereby constructing a circular artificial island 1 (caisson frame 3). Thereafter, water (seawater) inside the caisson frame 3 is extracted by a pump or the like, a waterproof sheet 6 is laid on the bottom 5 of the caisson frame 3, and the edge of the waterproof sheet 6 is attached to the caisson frame 3. Up, and fix the edge of the waterproof sheet 6 to the upper surface of the caisson frame.
The construction of the artificial island 1 is completed by installing the pump 7 with the purifying device on the upper surface of the caisson frame 3.

As described above, in the method of constructing an artificial island according to this embodiment, the caisson manufacturing process, the caisson floating process, the barge moving process, the caisson setting process, and the barge floating process are sequentially repeated a predetermined number of times. When the caisson 2 is installed on the bottom of the water in the caisson installation step, the caisson 2 is connected to the caisson 2 previously installed on the water bottom, so that the upper part of the annular caisson frame 3 is placed on the water surface. The caisson frame 3 can be easily constructed on the sea or the like as the artificial island 1 because the caisson frame 3 can be installed on the water bottom in a state of protruding from the water. The artificial island 1 constructed as described above can be used as a suitable place for dumping incineration ash of garbage, construction soil, industrial waste, and the like. When the waste M or the like is dumped inside the artificial island 1, the amount of water increased by this dumping is purified by the pump 7 with the purification device and discharged to the outside (outside sea).

The bottom 5 which is the bottom of the caisson frame 3 is made of bentonite concrete having high water-imperviousness.
Since the waterproof sheet 6 is provided on the inner peripheral surface of the caisson frame 3, water (seawater) outside the caisson frame 3 does not enter the inside of the caisson frame 3, and the caisson frame 3 No water leaks from the inside to the outside of 3. Therefore,
The inside of the artificial island 1 can be used as a more suitable place for dumping incineration ash of garbage, construction soil, industrial waste, and the like.

When constructing the vast artificial island 1 from the beginning, a huge amount of money and a construction period are required,
Considering the situation such as the amount of incineration ash, construction soil, industrial waste, etc., or the economic situation, it is better to construct an artificial island of a certain size at first than to construct a vast artificial island 1 from the beginning. In some cases, it is preferable to gradually expand according to the above-mentioned situation.

An example of the method for expanding an artificial island according to the present invention will be described below with reference to FIG. First, as shown in FIG. 4A, four caissons 2a, 2b, 2
A small artificial island 20 is constructed using c and 2d. The artificial island 20 is constructed using the same method as the above-described artificial island construction method. The caissons 2a to 2d have the same shape and the same size as the caisson 2, respectively.
Further, the caisson 2e to 2t to be described later
It is the same shape and same size as. A waterproof sheet 6a is laid inside the artificial island 20.

In order to enlarge the area of the artificial island 20 about four times in plan view, as shown in FIG. 4B, the following existing caisson moving installation step and a new caisson connection installation step are performed. . (1) Existing Caisson Moving Installation Step First, water (seawater) in the caissons 2c and 2d is extracted from the existing caissons constituting the artificial island (caisson frame) 20 by a pump or the like. Then, caisson 2c, 2d
Emerges.

Next, the barge 10 is sunk under the caisson 2c, and the barge 10 is lifted up.
The caisson 2c is loaded on the barge 10, the caisson 2c loaded on the barge 10 is moved so as to be positioned on an extension of the caisson 2b, and the barge 10 is settled at this position, By moving it horizontally,
Evacuate the barge 10 from below the caisson 2c,
By injecting water (seawater) into the caisson 2c, the caisson 2c is settled down again and installed on the water bottom with its upper part protruding from the water surface, and the caisson 2c is connected to the end face of the caisson 2b. .

Next, in the same manner as described above, the caisson 2d is moved by the barge 10 to the end of the re-installed caisson 2c to a position perpendicular to the caisson 2c. After evacuating the barge 10 from 2c, water (seawater) is injected into the caisson 2d,
The caisson 2d is settled again, and placed on the water bottom with its upper part protruding from the water surface, and the caisson 2d is connected at right angles to the end face of the caisson 2c.

(2) New caisson connection setting step Next, the barge 10 is set in the same manner as shown in FIG.
A new caisson 2e is manufactured above, and this caisson 2e
At the end side of the re-installed caisson 2d,
It is set on the bottom of the water with its upper part protruding from the surface of the water, and connected to the caisson 2d. Similarly, the caissons 2f to 2h are successively manufactured and installed on the bottom of the water, and the caissons 2e and 2f are
An annular artificial island 21 is formed by connecting f, 2g, caisson 2g, 2h, and caisson 2h, 2a, respectively.

On the other hand, inside the artificial island 21, FIG.
(B) and as shown in FIG. 5, the waterproof sheet 6 b is added to the waterproof sheet 6 a, the waterproof sheet is laid on the entire inside of the artificial island 21, and the end of the waterproof sheet is placed on the upper surface of the artificial island 21. Fix it. As a result, the artificial island 20 becomes approximately 4
The artificial island 21 is expanded to double the area.

In order to further extend the artificial island 21, the existing caisson is moved and installed in the same manner as described above.
Perform new caisson connection installation process. That is, in the existing caisson moving installation step, as shown in FIG.
The caisson 2c, 2b is lifted and moved, the caisson 2c is connected to the caisson 2d in a straight line, and the caisson 2b is connected to the caisson 2c at a right angle. Similarly, the caisson 2h, 2a is lifted and moved, the caisson 2h is connected to the caisson 2g in a straight line, and the caisson 2a is connected to the caisson 2h at a right angle.

Next, in the new caisson connection setting process, new caissons 2i to 2l are manufactured one after another and installed on the bottom of the water, and the caissons 2a and 2i are connected to each other.
A circular artificial island 22 is formed by connecting i, 2j, caisson 2j, 2k, caisson 2k, 2l, caisson 21 and 2b, respectively. On the other hand, inside the artificial island 22, the waterproof sheets 6a, 6
b, a waterproof sheet 6c is added around the central portion of the artificial island 22 as a center, the waterproof sheet is laid on the entire inside of the artificial island 22, and the end of the waterproof sheet is fixed to the upper surface of the artificial island 22. . As described above, the artificial island 21 is further expanded into an artificial island 22.

In order to further extend the artificial island 22, the existing caisson is moved and installed in the same manner as described above.
Perform new caisson connection installation process. That is, in the existing caisson moving installation step, as shown in FIG.
The caisson 2c, 2d, and 2e are lifted and moved, and the caisson 2c is linearly connected to the caisson 2b, and the caisson 2d is connected to the caisson 2c at a right angle.
e is linearly connected to the caisson 2d. Similarly, the caisson 2h, 2g, and 2f are lifted and moved, and the caisson 2h is connected to the caisson 2a linearly, the caisson 2g is connected to the caisson 2h at right angles, and the caisson 2f is connected to the caisson 2g linearly. I do.

Next, in the new caisson connection setting process, new caissons 2m to 2p are manufactured one after another and installed on the bottom of the water, and the caissons 2e and 2m are connected to each other.
An annular artificial island 23 is formed by connecting m, 2n, caisson 2n, 2o, caisson 2o, 2p, caisson 2p, 2f, respectively. On the other hand, inside the artificial island 23, as described above,
The waterproof sheet 6d is attached to the artificial island 23 on the waterproof sheets 6b and 6c.
Continue around the center of the inside. As described above, the artificial island 22 is further expanded to become the artificial island 23.

In order to further extend the artificial island 23, the existing caisson is moved and installed in the same manner as described above.
Perform new caisson connection installation process. That is, in the existing caisson moving installation step, as shown in FIG.
The caisson 2c, 2b, 21 and 2k are levitated and moved, the caisson 2c is connected linearly to the caisson 2d, the caisson 2b is connected to the caisson 2c at right angles, and the caisson 2l is connected to the caisson 2b linearly. , Caisson 2
k is connected to caisson 2l in a straight line. Similarly, while moving the caisson 2h, 2a, 2i, 2j while floating, the caisson 2h is connected linearly to the caisson 2g, the caisson 2a is connected to the caisson 2h at a right angle, and the caisson 2h is connected.
i is connected to caisson 2a linearly, and caisson 2j is connected to caisson i.

Next, in the new caisson connection setting process, new caissons 2q to 2t are manufactured one after another and installed on the bottom of the water, and the caissons 2k and 2q are connected to each other.
An annular artificial island 24 is formed by connecting q, 2r, caisson 2r, 2s, caisson 2s, 2t, and caisson 2t, 2j, respectively. On the other hand, inside the artificial island 24, as described above,
The artificial sheet 24 is attached to the waterproof sheets 6c and 6d.
Continue around the center of the inside. As described above, the artificial island 23 is further expanded to become the artificial island 24.

As described above, according to the artificial island expanding method of the present embodiment, the existing caisson moving and re-installing step and the new caisson connecting and installing step are repeated a predetermined number of times as necessary, so that the The artificial island can be gradually expanded without causing the occurrence. Therefore, incineration ash,
The artificial island, that is, the place for dumping the incinerated ash, construction waste, industrial waste, and the like can be expanded according to the situation such as the amount of production of construction waste, industrial waste, and the like, or economic conditions.

By the way, when expanding the artificial island,
If the existing caisson is left as it is and a new caisson is installed so as to surround the outside, the existing caisson inside will be wasted, and incineration ash etc. will be dumped by the width of the caisson. Although the area of the place to be processed is reduced, such an event does not occur in the expansion method of this example.

In this embodiment, an example in which the artificial island 20 is expanded to the artificial islands 21 to 24 centering on the artificial island 20 has been described. However, the present invention is not limited to this, and a part of the existing caisson may be used. Is moved to a position where the caisson frame (artificial island) is opened, and the caisson is settled again at this position, so that the upper part of the caisson protrudes from the water surface. Any method may be used as long as the artificial island is circularly expanded by installing the caisson, the existing caisson, and the new caisson in the state where the artificial island is installed in the water bottom.

[0051]

As described above, according to the first aspect of the present invention,
According to the artificial island, an annular caisson frame was formed by connecting a plurality of caissons in an annular shape in plan view, and the caisson frame was installed on the water bottom with its upper surface protruding from the water surface. The inside of the caisson frame can be used as a suitable place for dumping incineration ash of garbage, construction soil, industrial waste, and the like.

According to the artificial island of claim 2, the waterproof layer is formed on the water bottom located on the inner bottom of the caisson frame and on the inner peripheral surface of the caisson frame. No outside water (seawater) enters the inside, and no water leaks from the inside of the caisson frame to the outside. Therefore, the inside of the caisson frame can be used as a more suitable place for dumping incineration ash of garbage, construction residue, industrial waste, and the like.

According to the third aspect of the present invention, the caisson manufacturing process, the caisson floating process, the barge moving process, the caisson setting process, and the barge floating process are sequentially and repeatedly performed a predetermined number of times. When installing a caisson on the bottom of the water in the caisson installation step, by connecting this caisson to another caisson previously installed on the water bottom,
The annular caisson frame can be installed on the water bottom with its upper part protruding from the water surface, that is, the caisson frame can be easily constructed on the sea or the like as an artificial island.

According to the method for expanding an artificial island according to the fourth aspect, the existing caisson moving and re-installing step and the new caisson connecting and installing step are repeated a predetermined number of times as necessary, thereby preventing waste of the caisson. The artificial island can be gradually expanded, so that the artificial island, that is, the incinerated ash, construction residual soil, industrial waste, etc. It is possible to expand the place where the waste and the like are dumped.

[Brief description of the drawings]

FIG. 1 shows an example of an artificial island according to the present invention, and is a perspective view showing a state where an artificial island is installed on the sea.

FIG. 2 is a sectional view of the same.

FIG. 3 is a process drawing showing in cross section an example of the method for constructing an artificial island according to the present invention.

FIG. 4 is a process diagram showing an example of a method of expanding an artificial island according to the present invention in a plan view.

FIG. 5 is a process diagram illustrating a method of adding a waterproof sheet in a cross section, for explaining a method of expanding an artificial island according to the present invention.

[Explanation of symbols]

 1,20,21,22,23,24 Artificial island 2,2a-2t Caisson 3 Caisson frame 6,6a-6e Waterproof sheet (waterproof layer) 10 boats

Claims (4)

[Claims] An annular caisson frame is formed by connecting a plurality of caissons in an annular shape in a plan view, and the caisson frame is installed on the water bottom with its upper surface protruding from the water surface. And an artificial island. 2. The artificial island according to claim 1, wherein a waterproof layer is formed on a water bottom located at a bottom inside the caisson frame and on an inner peripheral surface of the caisson frame. 3. A caisson manufacturing process for manufacturing a caisson on a barge, and after the caisson manufacturing process, the caisson is floated on the water in a state where the caisson is vertically separated from the barge by sinking the barge. And after the caisson floating step, a barge moving step of horizontally moving the barge away from the caisson, and after the barge moving step, the caisson is settled, A caisson setting step of setting the caisson on the water bottom with its upper part protruding from the water surface, and a barge floating step of floating the barge after the barge moving step, by sequentially repeating a predetermined number of times. A plurality of caisson is installed in an annular shape to form an annular caisson frame, and when the caisson is installed on the water bottom in the caisson installation process, the caisson is previously placed on the water bottom. A method for constructing an artificial island, wherein the artificial island is connected to another installed caisson. 4. A method of expanding an artificial island according to claim 1 or 2 or an artificial island constructed by the artificial island construction method according to claim 3, wherein the plurality of caisson frames are formed. By lifting a part of the existing caisson, moving the raised caisson to a position where the caisson frame is opened, and further lowering the caisson at this position, the caisson is The existing caisson moving and re-installing step of installing the caisson at the bottom with the upper part protruding from the water surface, the re-installed caisson re-installed in the existing caisson moving and re-installing step, the existing caisson, and a new caisson are formed into a ring And a new caisson connection installation step of installing the new caisson on the water bottom with its upper part protruding from the water surface, and How to expand the island.