JP2731946B2 - Underwater structure placement cushioning material - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an underwater structure for preventing a plurality of underwater structures, such as caissons, from being damaged by contact with each other in the water when the plurality of underwater structures are installed. The present invention relates to a cushioning material for installation.

2. Description of the Related Art Generally, when constructing an underwater structure such as a breakwater, a plurality of caisson and other underwater structures are individually constructed and launched on a land-based facility, and a tugboat or other ship is towed to the sea surface where the structure is installed. Water is poured into the hollow portion of the structure to sink it, and each is set at a predetermined position, and then filled with a filler having a large specific gravity, such as sand or concrete, to obtain a structure that can withstand waves.

In the installation work of such an underwater structure, there is no appropriate cushioning material for protecting the underwater structure during the installation work.

Problems to be Solved by the Invention However, underwater structures such as caissons before filling with fillers such as sand and concrete have a large hollowness, an apparent specific gravity is small, and the strength of the wall surface is low. During installation work in, unexpected sway may occur due to tides, winds, waves or work defects, and the structures may collide with each other and be damaged. In addition, it is very difficult to repair damaged underwater structures, which has increased the cost of repairs and increased the construction period.

Means and Solution for Solving the Problem The present invention relates to an invention of a buffer material for installing an underwater structure which solves such a problem, and has an elasticity having a hollow portion capable of filling a liquid such as water or seawater therein. It is characterized by comprising a bag, and an orifice capable of discharging a liquid such as water or seawater filled inside the bag to the outside of the bag.

Since the present invention is configured as described above, by installing the present cushioning material in advance at a place where there is a risk of collision of the underwater structure during the installation work, by filling with a liquid such as water or seawater and placing it. In the event of a danger of collision during work at an installation site on the sea floor, or by placing the cushioning material in the collision-risk location, the underwater structures will only impact on the cushioning material without directly colliding with each other. In the present cushioning material, the liquid filled by the load is ejected through the orifice, and the liquid deforms while generating a reaction force due to the resistance of the liquid passing through the orifice to perform a buffering action.

Embodiments Hereinafter, embodiments of the present invention shown in FIGS. 1 to 3 will be described.

FIG. 1 shows a first example of a cushioning material for installing an underwater structure according to the present invention.
FIG. 3 is a longitudinal sectional view showing the structure of the embodiment of the present invention, wherein a bag-like buffer 1 made of rubber or a rubber-like elastic body having an Ω-shaped cross-section is fixed to a top plate 4 of a pedestal 3 by mounting fittings 2 on water honey. Thus, the hollow portion 5 is formed.

The pedestal 3 is formed by welding and assembling steel plates.
The hollow portion 9 is formed by integrally connecting one end surface of the short rectangular cylindrical side plate 8 to the mounting plate 7 and integrally bonding the other end surface of the short rectangular cylindrical side plate 8 to the top plate 4. The hollow portion 5 of the buffer 1 communicates with the hollow portion 9 of the pedestal 3 through an orifice 10 provided in the top plate 4, and the hollow portion 9 of the pedestal 3 and the outside are orifice provided in at least one side plate 8. Communicate through 11. The mounting plate 6 to the caisson 5 is previously fixed to the bottom side surface 6a of the caisson 6 by a not-shown upright bolt or a concrete screw, and before the caisson 6 begins to sink, the buffer 1 is attached to the mounting bracket 2
Is attached to the top plate 4 of the pedestal 3 so that the seawater
Is filled.

In the embodiment shown in FIG. 1, a concrete caisson 6 manufactured on land and towed to the surface of the installation site is a cargo handling machine such as a floating crane provided on a floating body as shown in FIG. It is installed on the installation sea floor by the device. At this time, the bottom side surface 6a of the caisson 6 being installed may collide with the side surface 6b of the already installed caisson 6 due to tide, wind, waves, or work defects.

In such a case, the cushioning material as described in the first embodiment is installed on the bottom side surface 6a of the caisson 6 where there is a fear of collision, and when the caisson 6 is submerged in the sea, the bag-like buffer 1
Since the hollow portion 5 is filled with seawater and the buffer 1 has elasticity and the diameter of the orifice 10 is small, the filled seawater can be easily discharged to the outside unless the pressure is applied to the buffer 1 from outside. Not released.

However, when the cushioning material installed in the caisson 6 collides with another already installed caisson 6 for some reason as described above, a load is applied to the buffer 1 and the hollow portion 5 is filled by the pressure. Seawater orifice 10
The seawater in the hollow portion 9 is further injected into the sea through the orifice 11. At this time, due to the viscous resistance of the seawater passing through the orifices 10 and 11, the buffer 1
Deforms while generating a reaction force, absorbs the energy of the collision, and alleviates the impact (see FIG. 4). Since the resilience of the buffer 1 that has absorbed the impact and released the seawater is small, the buffer 1 no longer recovers and finishes its mission. (See FIG. 7) FIG. 4 shows the reaction force indicating the elastic characteristic of the shock absorber 1 by taking the reaction force of the shock absorber 1 generated by the collision on the vertical axis and the deformation amount of the shock absorber 1 on the horizontal axis. -Deformation amount curve. The area enclosed by the horizontal axis and the curve indicates the amount of impact energy absorbed by the buffer 1.

In the first embodiment, the pedestal 3 is provided with the hollow portion 9 and the orifices 10 and 11 are provided in two stages. When the buffer 1 injects seawater, pressure is also generated in the hollow portion 9 to increase the injection resistance. As a result, the impact energy can be sufficiently absorbed.

FIG. 2 is a longitudinal sectional view showing the structure of the second embodiment, and a bag-shaped buffer 21 made of rubber or rubber-like elastic body having an inverted U-shaped cross-section, and integrally formed with the buffer 21. A hollow portion 23 is formed by the pedestal portion 22 formed of a plate-shaped hard thick elastic body.

The hollow portion 23 and the outside communicate with each other through an orifice 24 provided by bending the pedestal portion 22. Before the caisson 25 starts to sink, the buffer 21 has the bottom surface of the pedestal portion 22 nailed or adhered to the expected collision surface 25a of the caisson 25, and the hollow portion 23 is filled with seawater.

Alternatively, the buffer 21 is filled with seawater in the hollow portion 23 and prepared on the sea floor as an installation work site, and if necessary, a buffer such as a diver is prepared at a collision danger point 25a of the caisson 25 being installed by a site worker such as a diver. 21 can also be interposed.

In the second embodiment, the length of the orifice is made relatively long to increase the injection resistance, and is used as a fixed or portable one.

FIG. 3 is a longitudinal sectional view showing the structure of the third embodiment.
A hollow portion 34 is formed by a bag-like cushioning body 31 made of a rubber-like elastic body and a circular block-shaped base 33 for engaging an opening 32 on the longer diameter side of the rubber cone having an oval cross-sectional shape. I have. The hollow portion 34 and the outside communicate with each other through an orifice 35 provided at the center of a circular block-shaped base 33.
The buffer is filled with seawater and prepared on the sea floor as an installation work site, and if necessary, a site worker such as a diver can interpose the prepared buffer material at the collision danger point 36a of the caisson 36 being installed. It has become.

In the third embodiment, the structure is simplified to make it portable and easy to use.

Effect of the Invention In the present invention, since the reaction force is generated by viscous resistance at the time of passing through the orifice of the filled seawater, there is no rebound resilience and the underwater structure under installation is not shaken, and after absorbing the collision energy, it is restored. The gap between underwater structures can be reduced.

Further, the structure is simple and inexpensive, and even if left as it is after use, there is no adverse effect on others.

Furthermore, it can be set in advance, and since it is lightweight, it can be used on site as needed.

Furthermore, an appropriate size can be selected and used for an expected collision load.

By using the cushioning material for installing an underwater structure according to the present invention having such advantages, it is possible to prevent damage due to collision during installation work of the underwater structure, to eliminate difficult damage recovery work, and to realize an underwater building. Not only can the cost of the construction work be reduced, but also the construction period can be shortened.

Further, the worker does not need to be more nervous to the collision than necessary, so that the mental burden on the worker is reduced, and as a result, the work efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal section showing a structure of a first embodiment of a buffer material for arranging underwater structures according to the present invention, FIG. 2 is a longitudinal section showing a structure of a second embodiment, and FIG. 3 is a third embodiment. Longitudinal section showing the structure of
FIG. 4 is a reaction force-deformation curve showing the characteristics of the cushioning material of the present invention, FIG. 5 is a schematic diagram showing the installation state of a caisson, and FIG.
FIG. 7 is a schematic view showing a state where the cushioning material is acting during caisson installation, and FIG. 7 is a schematic view showing a state of the cushioning material remaining after the caisson installation is completed. DESCRIPTION OF SYMBOLS 1 ... buffer, 2 ... mounting bracket, 3 ... pedestal, 4 ... top plate, 5 ... hollow part, 6 ... caisson, 6a ... bottom side surface,
7 pedestal mounting plate, 8 short square tubular side plate, 9 hollow base, 10 orifice, 11 orifice, 21
... buffer, 22 ... pedestal, 23 ... hollow, 24 ... orifice, 25 ... caisson, 31 ... buffer, 32 ... opening,
33 ... Base, 35 ... Orifice.

Claims (1)

(57) [Claims] An elastic bag body having a hollow portion capable of being filled with a liquid such as water or seawater, which is a cushioning material attached to an underwater structure such as a caisson, and a water filled inside the bag body. Or, an orifice for discharging a liquid such as seawater to the outside of the bag body is provided.