JP2000257093A - Ballast tank for burying box and burying method of burying box using it - Google Patents

Abstract

(57) [Abstract] [Problem] It is possible to bury a buried box safely and at the correct position on the water bottom in a correct posture, and it can be reused as many times as possible without the hassle of assembling and dismantling work. Provided is a ballast tank for a submerged box that does not generate waste materials, and a submerged box using the same. SOLUTION: The ballast tank inflates and expands a flexible bag 1 while controlling its movement and deformation by a frame 2.
In a state in which contraction was allowed, valves V1 to V3 for injecting water and discharging air were connected to the bag body 1 so as to be detachably fixed to the sunk box TE. The submerging method is as follows. First, a valve V1 is used for injecting water into the inflated bag 1 filled with air, V2,
V3 is used for discharging air, water W is injected while maintaining the expanded shape, and the buried box TE is buried under the water by its weight.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for submerging a submerged box constituting a submerged tunnel on a water floor at a construction site.
The present invention relates to a new ballast tank for a submerged box functioning as a weight and a submerged box submerging method using the same.

[0002]

2. Description of the Related Art As a method of constructing a tunnel at the bottom of the water such as the seabed or riverbed, a plurality of buried boxes built on land docks are sequentially buried from both banks in a trench dug on the bottom of the water, and the adjacent buried land is buried. There is a so-called sinking method in which the tunnels are rigidly connected to each other while the water is stopped by an annular rubber gasket.

[0003] Although the submerged box used in this submerged construction method constitutes only a part of the tunnel, it has a size similar to that of a medium or large ship, and it is difficult to transport it on land. Therefore, usually, in a dock equipped with facilities that can build such a large buried box, only a steel box is built until it can be floated on the water, and it is transported to a long distance, construction site ing.

Then, the box arrived at the construction site is filled with concrete to complete the buried box.
As shown in (a), in a submerged box TE, a rigid ballast tank 91 is formed by using a steel plate 91a, a reinforcing material 91b, and the like.
The submerged box TE is submerged at the bottom of the water by filling it with water W and functioning as a weight. Then, connection work with the previous submerged box is performed, and then the water W in the ballast tank 91 is assembled.
In order to eliminate the dead space in the submerged box TE, the ballast tank 91 is dismantled and removed.

[0005]

However, as described above, the conventional ballast tank performs operations such as welding, drilling, and bolting using a steel plate or a reinforcing material in a narrow submerged box. It is necessary to assemble it, and after use, it is necessary to cut off the welded part, loosen the bolts, etc., and remove it in a narrow submerged box, all of which are troublesome and time consuming. There was a problem that a large amount of waste material was generated.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a new submerged burial system which does not require assembling or disassembling work like a conventional rigid ballast tank, and which can be reused many times without generating waste materials. An object of the present invention is to provide a box ballast tank and a method of burying a buried box using the ballast tank.

[0007]

In order to solve the above-mentioned problems, the inventors of the present invention installed a hull in a large tanker, for example, in an oil tank or the like. It has been studied to apply a ballast tank made of a flexible bag used for stabilization of the tank to the submerging of a submerged box (for example, JP-A-51-13908).
No. 5).

That is, a flexible bag is formed by a rubber sheet or the like reinforced with a reinforcing cloth.
Is placed in the submerged box TE in a deflated state shown by a solid line in FIG. 5 (b), for example, and water W is injected and filled on the water at the construction site, and the bag body is It was studied to inflate 92 and submerge the submerged box TE by its weight.

According to this method, it is considered that the bag body 92 can be used any number of times, and its installation and removal can be greatly simplified. However,
Simply arranging the bag body 92 in the buried box TE as described above, for example, during the operation of injecting the water W into the bag body 92, if the buried box TE is tilted due to waves, etc. As shown by the broken line in FIG.
Both of them are greatly inclined and tilted downward, and the inclination of the submerged box TE is amplified, making it impossible to submerge in the correct position on the water bottom in the correct posture,
It was also found that an accident such as overturning might occur.

Therefore, as a result of further study to prevent the movement and deformation of the bag, the structure of the ballast tank itself is controlled while restricting the movement and deformation of the bag in the length and width directions of the buried box. It is only necessary to provide a frame for removably fixing the bag in a submerged box while allowing the expansion and contraction of the internal volume due to injection of water or air, and to the bag. When the bag is filled with air, first, the bag is filled with air to be in an inflated state, and at least two valves connected to the bag are used for discharging air and for injecting water, respectively. The inventors have found that it is only necessary to replace the air in the bag body with water while maintaining the shape, and have completed the present invention.

[0011] Therefore, the ballast tank for a submerged box according to the present invention is formed of an elastomer sheet reinforced with a reinforcing cloth, and functions as a flexible bag body functioning as a main body of the ballast tank. While regulating movement and deformation in the length direction and the width direction, while allowing expansion and contraction of its internal volume, a frame body for removably fixing the bag body in the sinking box, At least two connected to the bag for injecting water and discharging air, respectively;
And two valves.

In the method of submerging a submerged box according to the present invention, at least two valves connected to the pouch are used for discharging air and injecting water, respectively, in an inflated state in which the pouch is filled with air. The air bag is filled with water by replacing air in the bag body with water while maintaining the inflated shape of the bag body.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings showing an example of the embodiment. First, as shown in FIGS. 1 and 2, the ballast tank for a submerged box in this example is a frame formed by combining a flexible bag 1 functioning as a main body of the ballast tank and steel reinforcing members 21 to 23. Body 2 and three valves V1 to V connected to the bag body 1
3 is provided.

The bag 1 is integrally formed of a vulcanized rubber sheet reinforced with a reinforcing cloth, and has a substantially cylindrical main body 10 and one outer periphery of the main body 10. A flange 11 protruding along the entire length of the cylinder along the axis of the cylinder, and a pair of ears formed to close both ends of the cylinder of the main body 10 continuously with the flange 11. 1
2 and 13 are provided. Also, through holes 12 for connecting the valves V1 to V3 are formed in the both ears 12 and 13, respectively.
a, 12b and 13a are formed.

As shown in FIG. 3, for example, the bag 1 is obtained by folding the sheet 1a into two parts, and forming the core of the flange 11 made of an unvulcanized adhesive rubber on each side other than the fold. Sheet 1b serving as a core and sheet 1 serving as a core of an ear part
It is manufactured by sandwiching c and 1d, vulcanizing and bonding to integrate. Since it is difficult to integrally vulcanize such a large sheet, the sheet 1a includes a plurality of vulcanized rubber sheets 1e formed in a strip shape having a fixed width and reinforced with a reinforcing cloth. It is manufactured by so-called width finishing, which is vulcanized and bonded via an adhesive rubber.

In order to form the above-mentioned through holes 12a, 12b and 13a in the sheets 1c and 1d, pipes serving as these through holes are previously inserted and arranged at predetermined positions. The frame body 2 includes the first to third reinforcing members 21 to 23, each of which is made of steel as described above, and the free expansion of the main body 10 of the bag body 1 as shown in the drawing.
It is configured by arranging and fixing the flange portion 11 surrounding the main body 10 and the ear portions 12 and 13 so as not to prevent shrinkage.

The first reinforcing member 21 sandwiches the flange portion 11 over the entire length between the flange portion 11 and the side wall TE1 of the buried box TE, and also includes a large number of anchor bolts Ab protruding from the side wall TE1. By screwing and tightening the nuts N1, respectively, the bag body 1 is restricted from moving and deforming mainly in the length direction of the buried box TE, and the bag body 1 is placed in the buried box TE. This is for fixing the axis of the cylinder of the main body 10 to the corner between the side wall TE1 and the bottom plate TE2 in parallel with the length direction of the submerged box TE. This fixing is easily released by releasing the screwing between the anchor bolt Ab and the nut N1. In other words, the bag body 1 is
Removably fixed inside.

Further, the second and third reinforcing members 22 and 23 are respectively bolted with the ear portions 12 and 13 of the bag body 1 therebetween, so that the bag body 1 is mainly placed in the width direction of the buried box TE. This is for restricting the movement and the deformation. In the fixed state, the valve V1 connected to the through hole 12a located below the bag 1 is for injecting air and water into the bag 1. Although not shown, an air supply pump, a water supply pump, a switching valve thereof, and the like are connected to the end of the valve V1.

A through hole 12b located above the bag 1
The valves V2 and V3 connected to 13a and 13a are respectively for discharging air from the bag 1 when water is injected into the bag 1 from the previous valve V1,
As the valves V2 and V3, for example, a safety valve that discharges air when the internal pressure of the bag body 1 exceeds a set value is used.

In order to submerge the submerged box from the water at the construction site to the water bottom by using the ballast tank for submerged box of this example having the above-mentioned components, first, as shown in FIG.
With the valve V3 closed and the valve V1 opened, air is injected into the bag 1 from the air supply pump (not shown) through the valve V1 as shown by a white arrow in the figure, and the bag 1 is purged with air. Is satisfied and the state is fully expanded (state shown in FIG. 1).

Next, as shown in FIG. 4B, the valve V2,
V3 is set to function as a safety valve, and water W is injected into the bag 1 from a water supply pump (not shown) through a valve V1 as shown by a black arrow in the figure. Then, the valve V
By the functions of V2 and V3, air is discharged to the outside of the bag 1 through the valves V2 and V3 as shown by solid arrows in the figure, while maintaining the inflated shape of the bag 1 shown in FIG. That is, the air in the bag 1 is gradually replaced with water while maintaining the inflated shape of the bag 1.

At this time, for example, when one of the exhaust valves V2 and V3 (in this case, the valve V3) is immersed in water, the submerged box is tilted due to, for example, the influence of waves and the like. V3 may be closed and exhaust may be continued through only one valve V2. When the air in the bag body 1 is replaced with the water W as described above, the buried box is buried in the water bottom by its weight.

The submerged box after submerging is connected to the previous submerged box as in the prior art. Then, after the connection is completed, the screwing between the anchor bolt Ab and the nut N1 is released in order to prevent a dead space from being generated in the buried box, and the bag 1 and the frame 2 are removed from the buried box. Can be removed. The removed bag 1, frame 2, etc. may be reused for another immersion box.

According to the submerging step, the frame 2
And the air inside the bag 1 is replaced with water while maintaining the inflated shape of the bag 1 by using the valves V1 to V3 as described above. If the buried box is tilted under the influence of waves, etc., due to the synergistic effect with the action of doing so, it will be prevented from amplifying the tilt due to the movement of water accompanying it, so overturning the buried box It is possible to safely immerse in the correct position on the water floor without any errors in the correct posture.

It should be noted that the configuration of the present invention is not limited to the examples shown in the drawings described above. For example, the shape of the bag, the arrangement of the frame, and the like can be appropriately changed according to the arrangement of these members in the immersion box. The valve is
The number is not limited to three as in the example of the figure, but may be two, or may be four or more as long as it is possible to inject water and discharge air therewith. The arrangement can also be appropriately changed according to the shape of the bag, the arrangement of the frame, and the like.

In addition, various design changes can be made without changing the gist of the present invention.

[0027]

As described in detail above, according to the present invention,
The buried box can be safely buried in the correct position at the bottom of the water and in the correct posture without overturning, and it can be reused any number of times without the hassle of assembling and dismantling work. This provides a unique operation and effect that a ballast tank for a submerged box that does not generate waste material and a method of submerging a submerged box using the same can be provided.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of an embodiment of a ballast tank for a submerged box of the present invention.

FIG. 2 is a sectional view of the ballast tank of the above example.

FIG. 3 is a perspective view showing a method of assembling a flexible bag in the ballast tank of the above example.

FIGS. 4 (a) to 4 (c) are explanatory views illustrating steps of a method of submerging a submerged box using the ballast tank of the above example.

FIG. 5A is a cross-sectional view showing an example of a conventional rigid ballast tank, and FIG. 5B is a cross-sectional view showing an example using only a flexible bag as a ballast tank.

[Explanation of symbols]

 1 bag body 2 frame body V1 to V3 valve TE buried box W water

Claims (2)

[Claims] 1. A ballast tank which is disposed in a submerged box constituting a submerged tunnel and fills water therein to function as a weight when the submerged box is submerged in the water floor, and is reinforced with a reinforcing cloth. A flexible bag that is formed of an elastomeric sheet and functions as the main body of the ballast tank, and the inner volume of the bag while regulating movement and deformation in the length and width directions of the immersion box In a state in which expansion and contraction of the bag are allowed, the bag for detachably fixing the bag in the immersion box, and for injecting water and discharging air respectively connected to the bag. A ballast tank for a buried box, comprising: at least two valves. 2. A method for submerging a submerged box at the bottom of a water by filling the bag body of the ballast tank for submerged tank according to claim 1 with water to function as a weight, wherein the bag is filled with air. In the inflated state, at least two valves connected to the bag are used to discharge air and inject water, respectively, to replace the air in the bag with water while maintaining the inflated shape of the bag. A method of submerging a submerged box.