JPH0598621A - Gravity-type wave control structure - Google Patents

Abstract

PURPOSE:To cope with great dynamic water pressure in a water area of big waves and great water depth, and improve earthquake resistance. CONSTITUTION:Beneath the bottom of a cylinder-type main body 2, a bottom plate 3, the diameter of which is larger than that of the cylinder-type main body is provided to form a cylinder structural body 1. A number of cylinder structural bodies are lined up with their bottom plates being in contact with each other to form gaps 4 between the respective cylinder structural bodies so that water can freely flow through the gaps. Further, vibration control materials 6 are mounted on the outside of the respective cylinder-type main bodies to serve as cushioning materials when the cylinder main bodies collide with each other due to vibration transmitted at the time of earthquake.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gravity type wave control structure in a harbor, a coast or the ocean.

[0002]

2. Description of the Related Art It is expected that harbor facilities constructed in the future such as offshore artificial islands will become deeper in water, and along with this, wave control structures will often be constructed in deep water. In such a case, it is very important to study the seismic resistance of the wave control structure. In deep water, the hydrodynamic pressure on a structure during an earthquake increases significantly. Therefore, it is desirable that the deep-water deep-wave control structure constructed in an earthquake-prone area such as Japan should be a structure in which the acting hydraulic pressure is as small as possible.

By the way, a wave control structure such as a breakwater is
Conventionally, the caisson is formed by using a quadrangular caisson both in cross section and in plan, but it is extremely disadvantageous under the conditions of large waves and deep water where the hydrodynamic pressure is large. For this reason, in recent years, development of a wave control structure in which cylindrical structures are arranged in series has been promoted. This structure uses a cylindrical caisson instead of the conventional square caisson.

[0004]

The above-mentioned cylindrical structure is
A single structure has a small hydrodynamic pressure that acts on it.However, when the cylinders are connected to form a wall-like structure, a large hydrodynamic pressure acts at the contact points of the cylinders, and the rectangular wall Since it is almost the same as the working hydraulic pressure, it is rarely used.

In view of the above situation, the present invention takes advantage of the cylindrical structure which has a small dynamic pressure acting as a single body, and can reduce the dynamic pressure acting as a wave controlling structure as a whole. It is intended to provide a wave control structure suitable for water depth conditions.

[0006]

As a result of intensive studies to solve the above-mentioned problems, the inventor of the present invention has found that a dynamic water pressure acting on the entire wall is greatly increased by opening a gap between adjacent cylinders. It was found to decrease. It was also found that the structure can be economically constructed because the cross section of the structure can be small if the acting hydraulic pressure is small.

Further, taking this one step further, the height of the structure constructed in the deep water becomes very large, so that the vibration transmitted during the earthquake is greatly increased at the upper part of the structure and the adjacent cylindrical structure The present invention has been completed by providing means for avoiding the collision of the above.

That is, the wave control structure according to claim 1 is
A large number of cylindrical structures 1 each having a bottom plate 3 larger than the diameter of the main body 2 are connected to the cylindrical main body 2 so that the bottom plates 3 and 3 are in contact with each other, and water flows out between the respective cylindrical structures 1 and 1. Gap that allows entry
It is characterized by forming 4,4.

In the wave control structure according to claim 2, the bottom plate 3,3 having a diameter larger than that of the main body 2 is provided on the cylindrical main body 2, and the damping material is provided on the outer surface of the upper and lower intermediate portions of the main body 2. 6,
A large number of cylindrical structures 1 to which 6 are attached are continuously provided so that the bottom plates 3 and 3 and the damping materials 6 and 6 are in contact with each other, and a gap 4 that allows water to flow in and out between the cylindrical structures 1 and 1. , 4 are formed.

[0010]

[Operation] The hydraulic pressure acting on the structure of the present invention was examined by experiments and the like.
It is the largest when the cylinder walls are joined to form the cylinder wall, and the hydraulic pressure decreases as the distance between the adjacent cylinder bodies 2, 2 increases. In the case of a cylindrical wall, the value of the hydraulic pressure increases as the angle increases from the direction in which the hydraulic pressure acts (vibration direction), and reaches the maximum at the contact points of each cylinder body 2, 2, but between the cylinder bodies 2, 2. If a gap is opened even a little, the hydraulic pressure will decrease considerably. For example, in a column of cylinders with a gap between the cylinder bodies 2, 2, the gap between the cylinder bodies 2, 2 is 1% of the diameter of the cylinder body 2.
By opening it, the total hydraulic force is 85%, also 8% of the diameter.
The combined hydraulic pressure in the gap will be reduced to 67%.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the wave control structure of the present invention will be described first with reference to FIG. 1. Reference numeral 1 is a cylindrical structure, which is made of concrete and has a cylindrical main body 2.
A circular bottom plate having a diameter larger than that of the main body 2 is provided at the lower end of the. In the illustrated embodiment, the main body 2 is hollow, but the main body 2 may be filled with a filling material.

The structure of the present invention comprises the above-mentioned cylindrical structures 1, 1
Are connected to each other with their bottom plates 3, 3 connected in a wall shape.
Thereby, the body 2, of each adjacent cylindrical structure 1, 1
Gaps 4, 4 are formed between the two.

FIG. 2 shows an example of application of the structure of the present invention to a hybrid breakwater installed on a mound 5 constructed on the sea floor. The hydraulic pressure acting on the structure due to waves, earthquakes, etc. escapes to the back side of the structure from the gaps 4, 4 between the cylindrical structures 1, 1 to control the waves, and The hydraulic pressure acting on the body 1 is greatly reduced.

When the structure of the present invention is constructed in deep water, the structure becomes high like a high-rise building. Therefore,
The height of the cylindrical structures 1 and 1 is correspondingly high. In such a case, the vibration transmitted from the ground at the time of an earthquake will be greatly amplified at the upper part of the structure, and there is a risk that adjacent cylindrical structures 1, 1 will collide with each other. FIG. 3 shows an embodiment for applying to the above-mentioned high structure. That is,
In the cylindrical structure 1 described above, at a position adjacent to at least another cylindrical structure 1 on the outer peripheral surface of the intermediate portion of the main body 2,
The structure has elastic dampers 6 and 6 having a thickness substantially equal to the difference in radius between the cylindrical structure 1 and the bottom plate 2.

In this embodiment, as shown in FIG. 4, if the cylindrical structures 1, 1 are connected in series with the bottom plates 3, 3 in contact with each other,
The intermediate portions of the main bodies 2 and 2 are joined to each other via the damping materials 6 and 6, whereby the vibration transmitted during the earthquake is damped. In addition, FIG. 3 shows the structure of this embodiment in the same manner as in the previous embodiment.
It shows an example of application to a hybrid breakwater installed on top of a building.

The planar shape of the bottom plate 2 of the cylindrical structure 1 is not limited to the circular shape as described above, but may be a quadrangular shape or a polygonal shape, or a circular shape and another bottom plate 2. It is also possible to cut the contacting surface into a straight line so that both adjacent bottom plates 2, 2 can be joined by the surface.

[0017]

As described above, in the wave control structure of the present invention, since the cylindrical structures are continuously provided and the gaps for allowing water to flow in and out are provided between the cylindrical bodies, The running water will flow through these gaps, so that the hydraulic pressure acting on the structure can be reduced, and as a result, the cross section of the structure can be made smaller, and the structure can be economically constructed.

Since the cylindrical structure which is a structural unit of the structure is provided with a bottom plate having a diameter larger than that of the main body of the cylinder on the bottom surface, a gap can be surely provided between the adjacent cylindrical structures, and The ground reaction force acting on the cylindrical structure also decreases,
It is also possible to easily form an arbitrary wall shape.

Further, according to the cylindrical structure provided with the damping material, it is possible to buffer the collision of each cylindrical structure due to an earthquake when the structure is constructed at a large water depth, and the structure at a large water depth can be buffered. The construction of things can also be put to practical use.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a structure of the present invention.

FIG. 2 is a perspective view showing an example of the same installation.

FIG. 3 is a perspective view showing another embodiment of the structure of the present invention.

FIG. 4 is a perspective view showing an example of the same installation.

[Explanation of symbols]

 1 Cylindrical structure 2 Main body 3 Bottom plate 4 Gap 5 Mound 6 Damper

Claims (2)

[Claims] 1. A cylindrical main body is provided with a large number of cylindrical structures each having a bottom plate larger than the diameter of the main body, the bottom plates being in contact with each other, and the water is allowed to flow in and out between the cylindrical structures. A gravitational wave control structure characterized by having a gap formed therein. 2. A cylindrical main body is provided with a bottom plate larger than the diameter of the main body, and a large number of cylindrical structures each having a vibration damping material attached to the outer surface of the upper and lower intermediate portions of the main body are mutually attached to the bottom plate and the vibration damping material. A gravitational wave control structure, characterized in that a gap that allows water to flow in and out is formed between each of the cylindrical structures in contact with each other.