JP2920170B2 - Caisson manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a caisson manufacturing method for constructing a concrete caisson used for a bay shore facility, a pier foundation, or the like.

[0002]

2. Description of the Related Art Conventionally, the construction of concrete caisson is
It uses a caisson yard built on land facing the sea and a floating dock moored at the quay.

[0003] In the caisson production yard, a built caisson is launched using a ramp that leads into the sea, or a launching platform that descends below the surface is used, and the built caisson is moved onto the platform. After letting
A method of launching the platform by lowering the platform below the water surface has been adopted.

[0004] When a floating dock is used, it is moored to an existing quay or the like, a caisson is built on the floating dock, and after the construction is completed, the floating dock is lowered and the caisson is launched. I try to make it.

[0005]

In the above-mentioned conventional method of manufacturing a caisson in a production yard or a floating dock, a land where a production yard can be formed and a floating dock can be moored near a caisson installation point. A quay is required.

[0006] Therefore, when such a place cannot be secured, for example, in the case of construction on an isolated island or expansion of a power station port, it is necessary to manufacture a caisson in a remote place and tow a long distance to the installation point. There was a problem in the process and safety.

The present invention has been made in view of such a conventional problem,
The aim was to provide a caisson manufacturing method that could make caisson in the vicinity of the caisson installation location even if it was difficult to lay a caisson production yard near the planned caisson installation site or moor the floating dock to the quay etc. Things.

[0008]

SUMMARY OF THE INVENTION The features of the present invention for solving the conventional problems as described above and achieving the intended purpose are as follows.
Using a caisson working platform supported on a fixed structure support that is capable of ascending and descending below the water surface above the water surface, a concrete caisson is sequentially built on the platform above the bottom, and the caisson A caisson for lowering the platform below the water surface in response to increasing bulk
In the manufacturing method, as a support for the fixed structure, on the seabed
Use a temporary caisson that is settled in a temporary storage state
Is to do.

The caisson production platform is supported.
Can be moved up and down through multiple suspension-type lifting drives
It is preferable to support it.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, reference numerals 10 and 10 denote fixed-structure supports installed in a closed or near water area such as an inlet. Each of the supports 10 and 10 is constituted by a caisson sunk on a foundation 3 or 3 formed on the water bottom 1, and their upper ends are temporarily placed in a state of protruding from the water surface 2 by a predetermined height. ing.

The two supports 10, 10 are installed at a fixed distance from each other, and work floors 12, 12 are provided so as to protrude above the opposing sides.

On the working floors 12, 12 of both supports 10, 10, suspension type lifting / lowering drive units 20, 20,... Comprising a number of hoists are arranged side by side. The lifting drive devices 20, 20,... Drive the hoisting means in synchronization with each other by an automatic control device, and the suspension wires 23, 23,. It has become so.

A caisson-made platform 30 is suspended between the two supports 10, 10.
Are suspended horizontally at the lower ends of the hanging wires 23, 23,. That is, platform 3
Numeral 0 is supported so as to be lifted and lowered between the two supports 10 and 10 while maintaining a horizontal state with the suspension lifting and lowering drive devices 20 and 20. I have.

Are fixed on both supports 10, 10, respectively.
A girder 47 for a shuttle crane is provided between 8, 48. A shuttle crane 40 is supported below the girder 47 so as to be able to run freely. The girder 47 can be extended to the land side for supplying materials and the like.

In manufacturing the caisson 100, first,
As shown in FIG. 2, the platform 30 is raised to the uppermost position on the water surface, the formwork is assembled on the platform 30, concrete is cast, and the first
The casting lot part 101 (bottom part) is manufactured. Next, the first
After solidification and curing of the casting lot part 101, a formwork is assembled above the casting lot part 101 and concrete is cast to produce a second casting lot part 102. After solidification and curing of the second casting lot portion 102, the second casting lot portion 102
The platform 30 is lowered by the same height as that of the platform 30.

Further, on the second casting lot portion 102,
The third casting lot portion 103 is manufactured by assembling the formwork and casting concrete. Then, when the curing of the third casting lot portion 103 is completed, the platform 30 has the same height as the height of the manufactured third casting lot portion 103.
Is lowered. As a result, the platform 30 and the first and second casting lot portions 10 of the caisson 100 being manufactured.
1,102 sink below the surface of the water. Similarly, a fourth casting lot portion 104 is formed on the third casting lot portion 103 and then settled, and the third casting lot portion 103 is submerged in water. As shown in FIG. A fifth casting lot portion 105 (uppermost portion) is manufactured on the setting lot portion 104.

As described above, when the caisson 100 is being manufactured, the platform 30 is lowered and the cured lot portions 101, 102,... Are sequentially submerged in water, and buoyancy acts on the portions. Lifting device 2
Since the load of 0, 20,... Becomes small, it becomes possible to manufacture a caisson that is large in comparison with the driving force of the suspension lifting drive device 20, 20,.

Further, each casting lot portion 102,
103 is always kept at a constant height,
Work can be suitably performed using the work floors 12, 12 fixed to 0,10. In addition, the shuttle crane 4
The material can be suitably transported by using 0, and a large tower crane or the like is not required. The support 10,
10 can be used as a material storage area, so that a support barge is not required.

[0020]

As described above, in the caisson manufacturing method according to the present invention, a caisson is manufactured on a caisson working platform supported on a fixed structure support provided on the sea so as to be able to ascend and descend, thereby forming a manufacturing yard. Even if the land to be built or the quay for mooring the floating dock cannot be secured, a caisson can be manufactured and launched near the caisson installation point, and the construction cost is reduced especially when a large number of caisson are manufactured. be able to.

In constructing the caisson on the caisson working platform, the caisson is manufactured step by step from the lower portion to the upper portion, and the platform is lowered to submerge the caisson finished portion in the water. As a result, buoyancy acts on that portion, and the load on the suspension lifting drive device is reduced, so that a caisson larger than the driving force of the suspension lift drive device can be manufactured.

In addition, since the caisson is manufactured stepwise from the lower part to the upper part and the platform is lowered, the part to be manufactured of the caisson is maintained at a constant height, so that two supporting members are provided. A shuttle crane that moves along a girder erected between the bodies can be used, and a large tower crane or the like is not required.

Further, by using a caisson temporarily placed on the bottom of the water as a support of a fixed structure for supporting the caisson working platform, it can be re-emerged, moved to another place, and reused. In addition, since the upper surface of the support using the caisson can be used as a material storage area, there is an advantage that there is no need for hinterland or a pallet.

[Brief description of the drawings]

FIG. 1 is an example of an embodiment of a caisson manufacturing method according to the present invention, and is an elevation view showing a completed state of a caisson.

FIG. 2 is an elevation view showing a state in which a first casting lot portion (bottom portion) of a caisson is manufactured.

FIG. 3 is an elevational view showing a state where a fifth casting lot portion (uppermost portion) of a caisson is manufactured.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Water bottom 2 Water surface 3 Foundation 10 Support 12 Work floor 20 Suspension elevating drive device 23 Suspension wire 30 Platform 40 Shuttle crane 47 Digit 48 Fixed leg 100 Caisson 101 First casting lot part 102 Second casting lot part 103 3 casting lot portion 104 4th casting lot portion 105 5th casting lot portion

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-66834 (JP, A) JP-A-9-158193 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) E02D 23/00

Claims (2)

(57) [Claims] 1. A caisson working platform, which is supported on a fixed structure support so as to be able to ascend and descend from above the water surface to below the water surface, and a concrete caisson is sequentially constructed on the platform above the bottom. and, characterized by the use of a temporary caisson the platform as a support for the fixed structure at caisson fabrication method of lowering the underwater and placed precipitated the temporary state to the seabed in accordance with the bulky increase of the caisson caisson production method to be as. 2. A caisson working platform is supported.
Can be moved up and down via a number of suspension type lifting drives
The caisson manufacturing method according to claim 1, wherein the caisson manufacturing method is supported.