JPH1193140A - Cut-off structure of caisson and caisson temporary closing method using cut-off structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cut-off structure to be durable against repeated use and reliably prevent leakage of water to the interior of a caisson. SOLUTION: An air bag 2 is mounted on a bottom part 1a of a caisson 1. The air bag 2 is provided with a tube 4 formed of an elastically deformable material; a covering member 5 attached to a part of the outer surface of the tube 4; and an air valve 6 to feed air to the tube 4. The tube 4 is expanded by a pressed in air pressure. When the caisson 1 seats on a foundation part 3, the air bag 2 is adhered to the respective members between the bottom part 1a of the caisson 1 and the foundation part 3 to prevent leakage of water to the interior of the caisson 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproof structure for preventing leakage of water from the outside into a caisson in construction of a structure underwater.

[0002]

2. Description of the Related Art In a work for reinforcing an underwater structure such as an existing pier, it is necessary to create a water-free work space around the pier and the like. For this purpose, a caisson or panel material (hereinafter, referred to as a “caisson”) having a size considering the work space surrounding the pier or the like is assembled in advance, and is installed around the pier or the like using a suitable means to perform a temporary deadline.

The water in the area surrounded by the caisson must be drained to prevent water outside the caisson from leaking into the working space inside the caisson. Therefore,
In the conventional waterproof structure, rubber packing is interposed between the existing base part on which the caisson lands and the bottom of the caisson,
Sealing is done.

[0004]

However, the basic part is
Generally, it is a footing foundation, and is often not entirely smooth but uneven due to bare concrete. In addition, sediment and the like are deposited on the top end of the foundation, and even if this is removed, fine soil particles and sludge remain. For this reason, ordinary rubber packing cannot fill the gap, and underwater concrete etc. is cast on both sides of the caisson,
It is generally used as a waterproof material.

[0005] Therefore, since the caisson is buried in concrete, it is difficult to convert the caisson to the next construction, and installation and removal of underwater concrete and the like require a lot of cost. In addition, when the waterproof material is damaged, replacement and repair are difficult.

In view of the above, an object of the present invention is to provide a water blocking structure in a caisson which has a reliable sealing performance regardless of the condition of the foundation and can be diverted to other works any number of times.

[0007]

Means for Solving the Problems According to the present invention, there is provided a water stopping structure which is disposed between a caisson and a foundation on which the caisson lands, and which prevents water from leaking into the caisson. The tube made of the elastically deformable material is detachably mounted on the outer surface of the caisson.

An elastic covering member is attached to a part of the outer surface of the tube, and the tube can be contracted and expanded by changing the pressure of the press-fitted fluid,
A guide plate is provided on the outer surface of the caisson to abut against the side surface of the tube to restrict expansion.

As a result, the tube expands in the space surrounded by the outer surface of the caisson, the base, and the guide plate, so that the tube is elastically deformed and comes into close contact with the base, thereby reliably preventing water from leaking into the caisson. can do. In addition, the presence of the covering member enables the sealing performance to be improved because even if there are minute irregularities on the base portion, the sealing member is brought into close contact with the gap by crushing the gap.

[0010] A socket for connecting the tubes is provided. Thus, by arranging a plurality of tubes in combination, it is possible to easily cope with caissons of various shapes. Therefore, the tube can be made simple.

When the caisson is temporarily closed using the above-mentioned water-stop structure, a tube and a socket are combined in advance in accordance with the shape of the caisson and mounted on the caisson, and the caisson is arranged around the target structure. The caisson is fixed to the caisson by attaching it to the base, and the fluid is supplied to the tube to expand it, and the tube is tightly sealed between the outer surface of the caisson and the base to seal the caisson. To prevent water leakage and drain the caisson.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, an air bag 2 mounted on a bottom 1a of a caisson 1 is used in a water stopping structure according to the present embodiment, and the caisson 1 is mounted on an existing foundation 3 such as a pier. When landing, the bottom 1a of the caisson 1 and the base 3
And a structure for preventing water leakage into the caisson 1.

As shown in FIG. 2, the air bag 2 includes a tube 4 made of an elastically deformable material into which air is press-fitted, a covering member 5 attached to a part of the outer surface of the tube 4, and a tube 4. And an air valve 6 for supplying air to the tube 4. The tube 4 expands and contracts by changing the air pressure to be press-fitted.

The tube 4 is made of rubber similar to a tire tube, such as butyl rubber, and has a cylindrical body formed in a cylindrical shape. Both ends of the tube 4 are closed by bonding a hemispherical cap 7 with an adhesive. You.

The covering member 5 is made of a closed-cell sponge rubber such as a flat neoprene sponge rubber, and is adhered to the upper and lower surfaces of the straight body of the tube 4.

The air valve 6 is a general tire valve, and is attached to an injection hole formed in the upper surface of the tube 4 through the covering member 5.

The caisson 1 has a double-walled steel shell structure composed of an outer shell and an inner shell. The caisson 1 has a rectangular shape in a plan view, one side of which is divided, and a hinge 1b on the other side facing the other side. It is opened and closed at the center. A plurality of airbags 2 are arranged in a square shape along the bottom 1a of the caisson 1. Therefore, a socket 8 for connecting the tubes 4 to each other is provided.

As shown in FIGS. 3 and 4, the socket 8 is hollow or has a hemispherical recess so that the cap 7 of the adjacent tube 4 can be fitted therein.
It is formed from a flexible rubber or plastic, such as a laminated neoprene sponge rubber or a neoprene rubber mass, so that it can be in close contact with the body. And socket 8
Are fixed to the middle and four corners of each side of the bottom 1a of the caisson 1 by an adhesive, respectively, and there are two types depending on the arrangement location. That is, the middle type arranged in the middle can fit the tubes 4 on both sides as shown in FIG.
The tube 4 can be fitted at an angle of 90 degrees as shown in FIG.

Further, a pair of guide plates 9 are provided on the bottom 1a of the caisson 1 to abut against the side surface of the tube 4 to restrict the expansion and prevent the expansion. The guide plate 9
The sockets 8 are arranged in parallel with each other, and are detachably attached to the caisson 1 by bolts.

Thus, when air is supplied to the tube 4 and the air bag 2 is inflated, both sides of the air bag 2 are brought into close contact with the guide plate 9 so that the tube 4 does not protrude. When the caisson 1 lands on the base 3, the airbag 2 is deformed in a space surrounded by the bottom 1a of the caisson 1, the base 3, and the guide plate 9, as shown in FIG. By this, the inside and outside of the caisson 1 are shut off and water is stopped.

Next, a caisson temporary closing method using the airbag 2 in the repair work of an existing pier underwater will be described with reference to FIG. First, a caisson 1 is manufactured for each block at a factory, and each block is transported to an assembly yard by land transportation, towing, or the like to assemble the caisson 1. After the assembly is completed, the socket 8 is set at a predetermined position according to the shape of the caisson 1, attached by an adhesive, and then the guide plate 9 is attached.

Next, the air bag 2 is mounted on the caisson 1. The tube 4 is inserted between the guide plates 9 and fitted into the socket 8. At this time, the air valve 6 is inserted into a hole provided in the bottom 1a of the caisson 1 to perform air injection piping. This air injection pipe uses a low pressure pipe and supplies air by a compressor. A valve for each air bag 2 is provided in the air injection pipe, and air can be supplied to the tube 4 by opening and closing the valve. Then, in order to keep the airbag 2 in close contact with the socket 8 so that it does not come out, a small amount of air is
Put in. However, the guide plate 9 is not attached to the divided portion 1c and the hinge portion 1b of the caisson 1. The air bag 2 located here has one side detached from the socket 8, the valve is closed, and the tube 4 is not filled with air.

Then, as shown in FIG. 6, the caisson 1 is landed and floated in a closed state, and towed to the site by the tugboat 10. When arriving at the site, the caisson 1 is opened as shown in FIG. At this time, the top end of the base portion 3 on which the caisson 1 is to be landed is dredged to remove accumulated sediment. Next, as shown in FIG. 8, when the caisson 1 is closed, the tube 4 of the airbag 2 in the dividing portion 1c and the hinge portion 1b is fitted into the socket 8, and air is supplied to bring the tube into close contact with the socket 8. After this,
The guide plate 9 is attached. At this time, the diver checks whether there is no air leakage from the airbag 2 and whether the airbag 2 is properly fitted in the socket 8.

Then, the caisson 1 is positioned for landing so that a desired working space is obtained, and water is injected into the double wall of the caisson 1 to settle as shown in FIG. Before the caisson 1 lands on the foundation 3, fine sand and sludge on the top end of the foundation 3 are removed by a water jet or the like. After fixing the caisson 1 that has landed thereon with the chemical anchor 12, air is supplied to the airbag 2 as shown in FIG.
At this time, the pressure in the tube 4 is set to a maximum of 2 kg / cm ² . Due to the inflation of the airbag 2, both side surfaces are in close contact with the guide plate 9, the upper surface is in close contact with the bottom 1 a of the caisson 1, and the lower surface is in close contact with the base portion 3. Thus, the airbag 2
Is pressed between the bottom 1 a of the caisson 1 and the base 3. This crimping force can be varied by adjusting the air pressure to be supplied.
Water can be reliably stopped by changing according to the situation. Since the socket 8 is also in close contact with the base 3,
There is no leakage from here.

Here, even if the base portion 3 has irregularities, it can be coped with by deforming the tube 4 according to the flexibility of the rubber, and the sealing performance can be maintained. In addition, fine irregularities such as soil particles existing at the top end of the base portion 3 can be dealt with by the cover member 5 being crushed.

After confirming that the air bag 2 is in close contact, the water area surrounded by the caisson 1 is drained to form a working space in the caisson 1. In addition, a shoring will be installed for caisson 1. At this time, since the water area outside the caisson 1 is sealed by the airbag 2,
Water does not leak into the caisson 1 from outside.

When the construction of the pier 11 is completed and the construction is completed, the air bag 2 is evacuated, water is injected into the caisson 1, and the caisson 1 is released from being fixed. The caisson 1 is lifted by draining the inside of the double wall of the caisson 1, the airbag 2 in the hinge portion 1 b and the split portion 1 c is removed from the socket 8, the caisson 1 is opened, and the pier 1 is opened.
Remove from around 1 and tow to other places.

Therefore, by inflating the air bag 2 when it is desired to stop water, and evacuating and contracting the air bag 2 when it is unnecessary, the air bag 2 can be used repeatedly, and a water stopping structure that can be diverted to other works. can get.

Further, since the airbag 2 can be elastically deformed, the airbag 2 can be deformed according to the condition of the caisson 1 and the base portion 3 so that the sealing performance can be maintained and the water can be reliably stopped. Moreover, since the airbag 2 has a simple structure, it can be easily attached to the caisson 1 and is easy to work. Further, since the airbag 2 is not fixed to the caisson 1, it can be attached and detached. It can be easily replaced simply by removing it from the socket 8, and is excellent in maintainability. In addition, since the materials used are commercially available, they can be manufactured at low cost and can be easily repaired.

It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that many modifications and changes can be made to the above-described embodiment within the scope of the present invention. For example, as shown in FIG. 11, the air bag 2 may be attached to the side surface of the caisson 1, and the outer surface of the caisson 1 may be appropriately changed according to the place where the caisson 1 is installed.
Here, the caisson 1 may be used not only for construction of a structure underwater but also for construction performed underground, and the airbag 2 prevents intrusion of groundwater.

The shape of the caisson 1 is not limited to a square, but may be a rectangle, a circle, or an ellipse.
What is necessary is just to arrange | position the airbag 2 and the socket 8 as shown in FIG. Therefore, the airbag 2 can be made straight, and it is not necessary to manufacture a curved one, and the cost can be reduced. Further, instead of inflating the airbag 2 with air, the airbag 2 may be inflated with another gas or water pressure.

[0032]

As is apparent from the above description, according to the present invention, a tube made of an elastically deformable material into which a fluid is press-fitted is detachably mounted on the outer surface of the caisson, and the base portion on which the caisson is to be landed. Prevent water leakage into the caisson between the caisson. This tube maintains the sealing performance by deforming according to the situation of the base part, so it can be used in other places, it can be used repeatedly, it is not disposable, it is very economical is there.

Since the elastic covering member is attached to a part of the outer surface of the tube, even if fine irregularities are present on the base portion, the irregularities can be absorbed, and the adhesion can be improved. And the sealing performance can be improved.

Also, since the tube can be contracted and expanded by changing the pressure of the press-fitted fluid,
The crimping force against the base can be controlled, and even if the sealing performance decreases over time when used in long-term construction, water can be reliably stopped by increasing the fluid pressure.

Also, by providing a guide plate on the outer surface of the caisson to abut against the side surface of the tube to restrict expansion,
In addition to being able to position the tube, the shape of the tube when inflated is adjusted so that it does not protrude, preventing damage from the outside, and maintaining the sealing performance even during long-term construction.

Since sockets for connecting the tubes are provided, by arranging a plurality of tubes in combination, it is possible to easily cope with caisson of various shapes. Therefore, the tube does not have to be manufactured according to the caisson, the tube can be unified into a simple shape, and versatility is enhanced.

By using this water stopping structure, water can be reliably prevented from leaking into the caisson by a simple operation in the temporary closing method using a caisson, so that the operation time can be reduced, and unnecessary work such as water leakage countermeasures is also eliminated. As a result, the progress of the construction can be accelerated.

[Brief description of the drawings]

FIG. 1 (a) is a view showing a water blocking structure in a caisson of the present invention, and FIG. 1 (b) is a view showing a state when the caisson is used.

2A and 2B show an airbag, wherein FIG. 2A is a longitudinal sectional view and FIG. 2B is a radial sectional view.

3A and 3B show an intermediate type socket, wherein FIG. 3A is a plan view and FIG. 3B is a side view.

FIG. 4 shows a corner type socket, (a) is a plan view,
(B) is a side view

Fig. 5 Flow chart of the temporary closing method

FIG. 6 is a diagram showing a state when a caisson is towed.

FIG. 7 is a diagram showing a state when a caisson is opened.

FIG. 8 is a diagram showing a state where a caisson surrounds a pier.

FIG. 9 is a view showing a caisson being settled.

FIG. 10 is a view showing a state in which a caisson lands on a foundation.

FIG. 11 is a diagram showing another mounting example of the airbag.

FIG. 12 is a diagram showing the arrangement of an airbag in another caisson.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Caisson 2 Air bag 3 Base part 4 Tube 5 Covering member 6 Air valve 7 Cap 8 Socket 9 Guide plate

Claims (4)

[Claims] 1. A water stopping structure disposed between a caisson and a base portion on which a caisson is to be landed to prevent water from leaking into the caisson, wherein a tube made of an elastically deformable material into which a fluid is press-fitted is provided. A water blocking structure in a caisson, which is detachably attached to an outer surface of the caisson. 2. An elastic covering member is attached to a part of the outer surface of the tube, and the tube can be contracted and expanded by changing the pressure of the press-fitted fluid. 2. A guide plate, which abuts on the guide plate to regulate expansion.
Waterproof structure in the caisson described. 3. The water stopping structure for a caisson according to claim 1, wherein a socket for connecting the tubes is provided, and a plurality of tubes are arranged according to the shape of the caisson. 4. A caisson in which a tube and a socket are combined according to the shape of the caisson and mounted on the caisson in advance, and the caisson is disposed around the target structure, and the caisson is fixed to the foundation by landing on the foundation. A fluid is supplied to the tube to expand it, and between the outer surface of the caisson and the base portion, the tube is brought into close contact with both to prevent water leakage from the outside into the caisson, and drain the caisson. Caisson temporary closing method.