JP2000248556A - Temporary shutoff construction method and temporary shutoff structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a temporary shutoff construction method and a temporary shutoff structure which can reduce both construction cost and a construction period by simplifying installation and removal. SOLUTION: In this temporary shutoff construction method, divided caissons 16(a), (b) are manufactured in a manufacturing yard nearby the repair work site of a bridge pier 10, and towed to the work site. A receiving base 30 is previously formed on a foundation 14. The divided caissons 16a, b manufactured in the manufacturing yard are combined together to be capable of being opened/ closed by interposing a hinge, but at towing, they are set afloat and carried, in the condition of closing the part capable of being opened/closed. When they are carried in the work site, the divided caissons 16(a), (b) are rotated right and left around the hinge, one end side is opened, and again closed so as to sandwich the bridge pier 10 between the divided caissons 16(a), (b). When combination of the divided caissons 16(a), (b) is completed, they are settled on the receiving base 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temporary deadline method and a temporary deadline structure, and more particularly to a temporary deadline method and a temporary deadline structure suitable for repairing underwater structures such as bridge foundations and repairing them. It is about the body.

[0002]

2. Description of the Related Art After a structure is constructed, deterioration over time, or damage and collapse due to an earthquake or the like, is not limited to a land-based structure, but also an underwater structure constructed on a river or sea, for example, And bridge foundations and seawalls.

[0003] When seismic reinforcement measures are taken for such underwater structures, conventionally, a steel sheet pile closing method or a liner plate method has been used. In the former steel sheet pile temporary closing method, steel sheet piles are interconnected and cast around an underwater structure to be subjected to seismic reinforcement to form a temporary closing work.
After draining the interior of the temporary cofferdam to make it dry, the underwater structures are subjected to seismic reinforcement and the steel sheet piles are removed.

[0004] In the latter liner plate method,
A liner plate is sequentially assembled around the underwater structure to be subjected to seismic reinforcement, a temporary deadline is formed, the interior of the temporary deadline is drained to a dry state, and the underwater structure is subjected to seismic reinforcement. And remove the liner plate.

[0005] However, such a conventional construction method has the technical problems described below, particularly when the construction site is affected by weather and sea conditions or when adjacent structures are close to each other. there were.

[0006]

That is, in the steel sheet pile temporary closing method, when working under a bridge, the work space on the sky side is restricted, so that a relatively short steel sheet pile is connected. This requires time and labor for the work, and requires large-scale installation facilities, which increases the construction period and construction cost.

Further, in the liner plate method, many parts are used on site, and many on-site operations such as plate assembly are performed. If the on-site operations increase, the construction period and construction costs increase due to the influence of weather and sea conditions. Invite.

SUMMARY OF THE INVENTION The present invention has been made in view of such conventional problems, and a temporary closing method and a temporary closing method capable of reducing both the construction cost and the construction period by simplifying installation and removal. It is to provide a temporary closing structure.

[0009]

SUMMARY OF THE INVENTION To achieve the above object, the present invention provides a method for surrounding a perimeter of an underwater structure such as a bridge foundation with a temporary cutoff structure, and disposing water in an inner portion of the temporary cutoff structure. In the temporary closing method of draining and repairing the underwater structure, such as repairing and reinforcing the underwater structure, the temporary closing structure includes a double-shelled cylindrical caisson formed in a closed cross-sectional shape, which is vertically extended. A plurality of divided caissons that are divided into at least two or more parts along a hinge, and openably and closably coupled with a hinge interposed between the divided parts, and the divided caissons transported to the repair work site for the underwater structure are expanded. Then, after being installed on the outer periphery of the underwater structure, the openable and closable divided portion of the split caisson is closed in a watertight state. According to the temporary closing method constructed as described above, the temporary closing structure is obtained by dividing a cylindrical caisson having a double-shell structure having a closed cross section into at least two or more along a vertical direction. The caisson has multiple split caissons that can be freely opened and closed by interposing hinges between the divided parts.The split caissons are transported to the underwater structure repair work site, expanded and installed around the underwater structure. Later, the openable and closable dividing part is installed by closing it in a watertight state. For this reason, the divided caisson can be manufactured in advance in a manufacturing yard or the like, and work on site can be significantly reduced. The temporary closing structure can be submerged and fixed on a cradle pre-formed on the foundation of the underwater structure. With this configuration, the temporary closing structure can be stably installed on the foundation of the underwater structure. A plurality of siding guides may be provided near the pedestal, and the split caisson may be provided with a guide projection that contacts the siding guide. When this configuration is employed, the temporary closing structure can be accurately guided on the cradle. Further, the present invention relates to a temporary deadline structure used for surrounding the outer periphery of an underwater structure such as a bridge foundation, draining water of an inner portion, and repairing the underwater structure, performing renovation such as reinforcement. The temporary closing structure includes a cylindrical caisson having a double shell structure formed in a closed cross-sectional shape,
It has a plurality of divided caissons divided into at least two or more along the vertical direction, and hingedly interposed between the divided portions of the divided caissons so as to be freely opened and closed. According to the temporary closing structure constructed as described above, the divided caisson can be manufactured in the manufacturing yard in advance, so that a high-quality double-shell caisson can be obtained.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. 1 to 10 show an embodiment of a temporary closing method and a temporary closing structure according to the present invention.

The embodiment shown in these figures, as shown in FIG. 1, repairs the underwater part of a pier 10 as a bridge foundation,
An example is shown in which the present invention is applied to a modification such as reinforcement.

A pier 10 to be rehabilitated is supported by a plurality of piles 12 which are driven into the underwater ground.
Has a plate-shaped pier foundation 14 connecting a plurality of pile heads.
Are formed, and the lower end of the pier 10 is
4 as one.

The temporary closing structure 16 used for repairing such a pier 10 is composed of a steel square tubular caisson having a double shell structure. Pair of divided caisson 16a, 16
b.

A pair of split caisson 16a, 16b
As shown in FIGS. 2 and 3, the outer shape is shown, and as shown in FIG. 4, the inner plate 160a, b and the outer plate 161a, b and the bottom plate 162a, b are formed in a substantially U-shape. Plates 163a, b, 164a, b and a plurality of partition plates 165
a and b.

The inner plates 160a, b and the outer plates 161a, b are vertically opposed to each other with a predetermined space therebetween.
Bottom plates 162a, b formed in a substantially U-shaped flat plate at the lower end thereof
Is fixed, and a pair of end plates 163a, b, 164a, b
The divided caissons 16a, 16b are fixed to the edges between the inner plates 160a, b and the outer plates 161a, b, which are vertically opposed to each other. It has a shell structure and is formed in a box shape with only the upper end open.

The plurality of partition plates 165a and 165b are provided with inner plates 160a and 160b and outer plates 161a and
The divided caissons 16a, 16b are divided into seven compartments 16 _{1a to} 16 _7a , 16 _{1b to} 16 _7b , respectively.

The pair of split caissons 16a and 16b are formed so that the U-shaped portions thereof abut each other so that each end plate 163 is closed.
a, b, 164a, b are arranged so as to face each other, and the hinge 18 is interposed between the one end plates 163a,
It is openably connected.

Bottom plate 16 of each divided caisson 16a, 16b
As shown in FIGS. 5 and 10, a stopper 20 for preventing the water-stop rubber 32 from being crushed when the divided caissons 16a and 16b are sunk and fixed on a receiving base 30 to be described later, as shown in FIGS. It is protruding. The stopper 20 is a bottom plate 162
a, b is located in the width direction of Shintomo Shin
Is provided so as to go around.

Further, as shown in FIG. 10, the divided caissons 16a, 16b are provided below the receiving plates 30a, 16b below the inner plates 160a, 16b of the divided caissons 16a, 16b.
The arc-shaped guide protrusions 22 that abut against the squatting guide 34 that guides the cradle 30 to a predetermined position when being sunk and fixed thereon.
Is fixed.

Furthermore, as shown in FIG. 5, the divided caissons 16a, 16b are provided below the inner plates 160a, b and the outer plates 161a, b of the respective divided caissons 16a, 16b.
When the b is fixed on the receiving base 30, a coupling flange 24 for preventing and stabilizing the lateral displacement is fixed by projecting by connecting the two with an anchor bolt.

On the other hand, in the case of this embodiment, the pier foundation 14
The pedestal 3 on which the temporary closing structure 16 is previously settled and fixed
0 is formed. 6 and 7 show details of the cradle 30. The cradle 30 has a main body 30a formed in a cross-girder shape.
, A height adjustment stand 30b, and a cast concrete layer 30c
It is composed of

The main body 30a is mainly made of H-shaped steel, and has two water-stop rubbers 32 fixed to the upper surface thereof at predetermined intervals. The waterproof rubber 32
Is provided in a rectangular ring shape so as to orbit along the shape of the main body 30a having a cross-girder shape.

The height adjusting base 30b is fixed to the lower end of the main body 30a, and is interposed at appropriate places so that the level of the main body 30a is uniform. Casting concrete layer 30c
Is to be cast underwater on the pier foundation 14, and in the case of this embodiment, is formed so that approximately half of the height of the main body 30a is embedded.

At the four inside corners of the cradle 30, there are provided siding guides 34 for guiding the temporary closing structure 16 to a predetermined position on the cradle 30 when the temporary closing structure 16 is sunk. The siding guide 34 of the present embodiment includes a support base 34a extending inward of the main body 30a so as to show the relationship between the divided caisson 16a, 16b sunk and the cradle 30 in FIG.
And a guide portion 34b erected on the support base 34a.

The guide portion 34b has two inclined surfaces inclined toward the main body 30a, and the temporary closing structure 16 is moved downward while the guide projections 22 contact the surfaces. It is positioned at a predetermined position on the cradle 30.

Next, a temporary closing method for repairing the pier 10 using the temporary closing structure 16 having the above configuration will be described with reference to FIG. In the temporary closing method according to the present invention, the divided caissons 16 a and 16 b constituting the temporary closing structure 16 are
It is manufactured in a production yard near the renovation work site of No. 0 and towed to the work site.

On the other hand, on the foundation 14 of the pier 10,
A cradle 30 is formed. The split caisson 16a, b manufactured in the manufacturing yard is connected to be openable and closable by interposing a hinge 18, but when towed, as shown in FIG. Lift and transport with the part closed.

The split caisson 16 which can be opened and closed
When the temporary closing structure 16 provided with a and b is transported to the construction site, as shown in FIG.
Is rotated left and right around the hinge 18 so that one end is opened, and the bridge pier 10 is sandwiched between the divided caissons 16a and 16b, and then closed again.

The opening and closing operations of the divided caissons 16a and 16b can be performed, for example, by operating a winch wire of a crane ship. And the split caisson 16a,
By connecting the end plates 165a and 165b with the bolts and nuts, a temporary closing structure 16 having a rectangular double-shell structure with a closed planar shape is formed.

At this time, each end plate 164a, b, 165a,
Water-stopping rubber is interposed between b. When the coupling of the divided caissons 16a and 16b is completed, the caisson is laid down. In the case of the present embodiment, this laying is performed by operating a valve.

That is, in the case of the present embodiment, each of the divided caissons 16a and 16b has seven compartments 16 each.
_1a ~ 16 _7a, 16 _1b is divided into a ~ 16 _7b, each compartment _{16 1 a ~16 7a, 16 1b} ~16 within _7b, as shown in FIG. 8, communicating Spoken valve A, the water injection valve B and emergency water injection valve C are arranged.

Each of the valves A, B, and C is, as shown in FIG.
The installation heights are different from each other, and the operation ends extend to near the upper ends of the divided caissons 16a and 16b. When submerging each divided caisson 16a, 16b,
This is performed by opening the communication valve A and the water injection valve B and introducing seawater into the inside.

At this time, the opening amounts of the communication valve A and the water injection valve B are appropriately adjusted, and the divided caisson 16a, 16b
To control the sinking posture of the ship. The emergency water injection valve C is used in abnormal weather such as a typhoon. Also,
The submerged caisson 16a, 16b may be laid by a method of injecting seawater with a submersible pump.

When the split caissons 16a and 16b are laid down by the injection of water and the lower ends thereof reach the vicinity of the cradle 30, the guide projections 22 come into contact with the guide portions 34b of the siding guide 34 as shown in FIG. The movement direction is regulated, and the sinking of the state-divided caisson 16a, 16b
When further proceeding, the divided caissons 16a, 16b are positioned by the positional relationship between the guide projection 22 and the siding guide 34, and the bottom plates 162a, b of the divided caissons 16a, 16b Placed on

The bottom plate 16 of each divided caisson 16a, 16b
When 2a and 2b are placed on the main body 30a of the cradle 30, the two water-stop rubbers 32 are provided on the main body 30a. In a deformed state, it is interposed between them, whereby the inside of the divided caisson 16a, 16b is stopped.

In this case, the crushing of the waterproof rubber 32 is prevented by the contact of the orbiting stopper 20 located on the center of the two orbited waterproof rubber 32 with the main body 30a. In other words, the amount of downward protrusion of the stopper 20 is caused by elastically deforming the waterproof rubber 32 so that the upper surface thereof becomes the bottom plate 162a, b
, So that the water stoppage on the inner side is ensured, so that further elastic deformation of the waterstop rubber 32 is prevented.

When the divided caissons 16a and 16b are placed on the cradle 30, anchor bolts are mounted on the coupling flange 24 to fix them.

When the fixing work is completed, the insides of the split caissons 16a and 16b are drained, and the underwater buried portion of the pier 10 is made a dry environment, and repair work such as repair and reinforcement is performed. Upon completion, the split caisson 16 is operated by performing the reverse of the above-described installation process.
The temporary closing structure 16 composed of a and 16b is removed and transported to the next pier 10 construction site.

According to the temporary closing method constructed as described above, the structure 16 to be the temporary closing works is to move the cylindrical caisson having the double shell structure formed in the closed cross section along the vertical direction. A pair of caissons 16a and 16b which are openably and closably coupled with a hinge 18 interposed between the divided portions.
16b is transported to the pier 10 repair work site, expanded and installed on the outer periphery of the pier 10, and then installed by closing the openable and closable portion in a watertight state.

For this reason, the divided caisson 16a, 16
b can be manufactured in a manufacturing yard or the like, so that the work on site can be greatly reduced, and the cost and period of construction can be reduced.

In the case of the present embodiment, the temporary closing structure 16 is fixed on the pedestal 30 previously formed on the pier foundation 14, so that the temporary closing structure 16 is connected to the foundation 14 of the pier 10. Can be stably installed on top.

Further, in the case of the present embodiment, the pedestal 30
Provided with a plurality of siding guides 34,
16b, the guide projections 22 that abut against the siding guide
Is provided, the temporary closing structure 16 can be smoothly placed on the receiving base 3.
0 can be guided.

Further, in this embodiment, the temporary closing structure 16 used for surrounding the outer periphery of the pier 10 and draining the water of the inner part to repair or reinforce the pier 10 includes:
A pair of divided caissons 16a and 16b, which are obtained by dividing a cylindrical caisson having a double shell structure formed into a closed cross-sectional shape into two along the vertical direction, have a pair of divided caissons 16a and 16b.
Are openably and closably connected with a hinge 18 interposed between the divided portions.

According to the temporary closing structure 16 configured as described above, the divided caissons 16a and 16b can be manufactured in the manufacturing yard in advance, so that a high-quality double-shell caisson can be obtained, and the structural There are very few defects,
It can contribute to reduction of the construction period and construction cost.

In the above-described embodiment, the square double-shell caisson is illustrated. However, the present invention is not limited to this shape, and other shapes such as a circle, an ellipse, and an oval may be used. And so on.

In the above embodiment, the case where the square double-shell caisson is divided into two is shown.
The number is not limited to two and may be two or more.

[0047]

As described above in detail in the embodiments,
According to the temporary closing method and the temporary closing structure according to the present invention, it is possible to reduce both the construction cost and the construction period.

[Brief description of the drawings]

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is an explanatory diagram sequentially showing steps of a temporary closing method according to the present invention.

FIG. 2 is a perspective view showing a state in which the temporary closing structure shown in FIG. 1 is expanded.

FIG. 3 is a perspective view showing a state in which the temporary closing structure shown in FIG. 1 is closed.

FIG. 4 is a plan view of the temporary closing structure shown in FIG. 1;

FIG. 5 is an enlarged view of a main part of FIG. 4;

FIG. 6 is a plan view of a cradle used in the temporary closing method according to the present invention.

FIG. 7 is a sectional view taken along line AA of FIG. 6;

FIG. 8 is an explanatory view of an arrangement of a valve installed in a compartment of the temporary shutoff structure shown in FIG. 1;

9 is an explanatory diagram of a height position of the valve shown in FIG.

FIG. 10 is an explanatory diagram of a final stage of the settlement of the temporary closing structure shown in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Bridge pier (underwater structure) 12 Pile 14 Bridge pier foundation 16 Closing structure 16a, b Split caisson 18 Hinge 20 Stopper 22 Guide projection 24 Coupling flange 30 Receiving stand 32 Water stop rubber 34 Deposition guide

Claims (4)

[Claims] 1. An underwater structure, such as a bridge foundation, is surrounded by a temporary cutoff structure, and water is drained from an inner portion of the temporary cutoff structure to repair or reinforce the underwater structure. In the temporary closing method to be performed, the temporary closing structure divides a cylindrical caisson having a double shell structure formed into a closed cross-sectional shape into at least two or more along a vertical direction, and a hinge between the divided portions. A plurality of divided caissons interposed and coupled to be openable and closable, wherein the divided caissons conveyed to the underwater structure repair work site are expanded and installed on the outer periphery of the underwater structure; A temporary closing method, characterized in that the openable and closable dividing part is closed in a watertight state. 2. The temporary closing method according to claim 1, wherein the temporary closing structure is sunk and fixed on a receiving base previously formed on a foundation of the underwater structure. 3. The temporary closing method according to claim 2, wherein a plurality of siding guides are provided in the vicinity of the pedestal, and the divided caissons are provided with guide projections which are in contact with the siding guides. 4. Surrounding the outer periphery of an underwater structure such as a bridge foundation and draining water in an inner portion to repair the underwater structure.
In the temporary closing structure used when performing renovation such as reinforcement, the temporary closing structure includes at least two or more cylindrical caissons having a double shell structure formed in a closed cross-sectional shape along a vertical direction. A plurality of divided caissons, the hinges being interposed between the divided caissons so as to be freely openable and closable.