JP2000257080A - Base isolation structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify execution and to prevent the breakage of a base isolation member even when a concrete board has irregularities by arranging a stratified irregular absorbing material on a concrete layer, installing a plurality of base isolation units inserted with spherical bodies between plates on it, and providing an upper structure on them. SOLUTION: A reinforced concrete board 14 serving as a concrete layer is formed on the ground, a plurality of base isolation units 12 are installed on foam polystyrene plates 13 spread on the reinforced concrete board 14, and a mat foundation 11 made of reinforced concrete is formed on the base isolation units 12 as part of an upper structure in this base isolation structure 10. Spherical bodies 12b made of a hard material such as a metal or a resin material having the hardness of a prescribed value or above are inserted between two plates 12a, 12c made of the same hard material into a one-layer state with a high density to form the base isolation unit 12. The foam polystyrene plates 13 serving as an irregularity absorbing material are compression-deformed to absorb irregularities when the upper surface of the reinforced concrete board 14 has fine irregularities.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a seismic isolation structure.

[0002]

2. Description of the Related Art As a conventional seismic isolation structure, as shown in FIG. 4, a self-leveling material 24 is poured into an upper surface of a concrete plate 25 to make it smooth, and a spherical body 23 is laid on the entire surface. There is a construction in which a plate material 22 is laid on the spherical body 23 to seal a joint between the plate materials 22, and then a reinforced concrete solid foundation 21 or a cloth foundation is constructed on the plate material 22. As another seismic isolation structure,
As shown in FIG. 5, seismic isolation units 32 each having a spherical body 32b sandwiched between two plate members 32a and 32c are laid on a concrete plate 33, and a joint between the seismic isolation units 32 is formed. After stopping, a solid foundation 21 or a cloth foundation is constructed on the seismic isolation unit 32.

[0003]

In the conventional seismic isolation structure shown in FIG. 4, the self-leveling material cannot be flowed unless the concrete strength of the concrete plate 25 has reached a predetermined level or more. Since it is necessary to apply a primer treatment to the concrete surface or apply a resin as a base treatment of the leveling material, it is troublesome and troublesome. Furthermore, when constructing and curing the self-leveling material, a large-scale temporary tent is required in order to prevent wind, rain and direct sunlight. In addition, the use of the self-leveling material causes several problems.

In the conventional seismic isolation structure shown in FIG. 5, when the concrete plate 33 is uneven, a part of the spherical body 32b is brought into a non-contact state with the plate material 32a due to the movement during the seismic isolation. The problem is that the load of the structure is locally concentrated on the spherical body 32b and the plate members 32a and 32c in contact with each other, and when the load is excessive, the spherical body 32b and the plate members 32a and 32c are damaged and seismic isolation performance is greatly reduced. There is.

Accordingly, the present invention has been made to solve the above-mentioned problems of the conventional apparatus, and its problem is that it can be easily constructed and seismically isolated even if the concrete plate has irregularities. An object of the present invention is to provide a seismic isolation structure that does not cause damage to members.

[0006]

SUMMARY OF THE INVENTION According to the present invention, there is provided an uneven absorbent material arranged in layers on a concrete layer, a plurality of seismic isolation units laid on the uneven absorbent material, An upper structure provided above, wherein the seismic isolation unit is provided with a plurality of spheres inserted between two plate members.

In the seismic isolation structure of the present invention, the unevenness absorbing material is a material which is softer than a plate material, and is capable of absorbing the unevenness by deforming the contact surface when the unevenness is in contact with the unevenness on the concrete layer. Yes, it is a material that can support the load of the upper structure, and a material that can be compressed and deformed when a local load is applied via the plate or spherical body of the seismic isolation unit. For example, it can be formed from a foamed resin material such as foamed polystyrene.

Further, the two plate members and the spherical body constituting the seismic isolation unit have a spherical shape while supporting the load of the upper structure when an external force is applied from the ground or the upper structure. Any material can be used as long as it can relatively roll or slide through the material. For example, the spherical body can be formed from a metal or resin material, and the plate material is a metal, resin material, or cement-based material. And the like.

Further, the concrete layer may be formed of reinforced concrete including reinforcing bars such as reinforcing bars, or may be formed only of concrete.

[0010]

The present invention will be described in more detail with reference to the following examples.
The present invention is not limited to these. FIG. 1 is a sectional view partially showing an embodiment of the present invention, in which a seismic isolation structure 10 includes a reinforced concrete plate 1 as a concrete layer.
4 is formed on the ground, a foamed polystyrene plate 13 is laid on the reinforced concrete plate 14, a plurality of seismic isolation units 12 are laid on the foamed polystyrene plate 13, and And a solid foundation 11 made of reinforced concrete as a part of the upper structure.

Here, the expanded polystyrene plate 13 is
When there is a small irregularity on the upper surface of the reinforced concrete plate 14, the irregular deformation is absorbed by compressive deformation. The seismic isolation unit 12 includes two plate members 12a and 12c,
During this time, the plurality of spherical bodies 12 inserted in a single layer at high density
b, the plate members 12a and 12c are formed of a metal having a predetermined hardness or more, a hard material such as a resin material or a cement material, and the spherical body 12b is similarly formed of a metal or a metal having a predetermined hardness or more. It is formed of a hard material such as a resin material.
In addition, at the time of construction, an adhesive tape (not shown) or the like is applied to the joints of the seismic isolation units 12 to perform sealing, and at the time of placing concrete for the solid foundation 11, concrete is inserted into the seismic isolation units 12 from the joints. Prevent entry.

FIGS. 3 (a) and 3 (b) are a plan view and a side view of the seismic isolation unit 12 during transportation and construction, respectively, and show the total length of the edges of the two plates 12a and 12c into which the spherical bodies 12b are inserted. Is provided with a spherical stopper 16. The spherical body stopper 16 is used to transfer the plate 1
This prevents the spherical body 12b from rolling out from between the portions 2a and 12c, and can be formed, for example, by a member having an L-shaped cross section with equal sides or unequal sides. The above-mentioned plate members 12a and 12c, the spherical body 12b and the spherical body stopper 16 are integrally fastened by a wide string material 17, for example, a packing resin tape or the like.

As described above, the seismic isolation unit 12 tied together is carried to the construction site and the expanded polystyrene plate 1
A plurality of units are laid on 3 and adjacent seismic isolation units 1
In order to remove the spherical stopper 16 on the side of the end, the cord material 17 is cut and pulled out. After removing the spherical stopper 16 and the string material 17, the seismic isolation unit 12
The joints are sealed with an adhesive tape (not shown) or the like.

Next, referring to FIGS. 1 and 2, the seismic isolation structure 1 will be described.
The operation of 0 will be described. Here, FIG. 2 is an enlarged cross-sectional view showing a state in which an external force such as an earthquake acts and moves in a seismic isolation manner. The irregularities that actually appear on concrete surfaces are gentle and widespread. When the seismic isolation structure 10 is formed, the expanded polystyrene plate 13 compresses and deforms to some extent to absorb the irregularity even if there is a small irregularity on the upper surface of the reinforced concrete plate 14, but the upper plate material On the lower surface of the base 12a and the solid foundation 11, a smooth and wide range of unevenness is formed in a complementary shape.

During the seismic isolation movement, a relative horizontal displacement occurs between the concrete plate 14 and the solid foundation 11, and the two plate materials are supported while supporting the load of the upper structure transmitted from the solid foundation 11. 12a and 12c roll through the spherical body 12b. At this time, since the upper plate member 12a has a smooth and wide area unevenness, the spherical body 1
There are a portion that contacts the portion 2b and a portion that does not contact the portion, and the contact portion applies concentrated loads to the spherical body 12b and the upper and lower plate members 12a and 12c. However, this concentrated load is transmitted to the expanded polystyrene plate 13 via the lower plate 12c before becoming excessive, and is absorbed by the compressive deformation of the expanded polystyrene plate 13, so that the plate 12
a, 12c and the spherical body 12b can be prevented from being damaged.

The irregularities actually appearing on the concrete surface and the like are gentle and widespread, and in FIG. 2, the irregularities of the concrete plate 14 are exaggerated and exaggerated for the sake of explanation. Plates 12a, 12 generated by land
The gap between c and the spherical body 12b is approximately 0.1 to 3.0 mm.
It is about. In addition, two plates 1 constituting the seismic isolation unit
As for 2a and 12c, one having a side of about 450 to 1800 mm and a thickness of about 3 to 10 mm can be used. Further, the spherical body 12b having a diameter of about 5 to 20 mm can be used. The expanded polystyrene plate 13
Can be used having a thickness of about 5 to 30 mm.

[0017]

According to the seismic isolation structure of the present invention, since the unevenness absorbing material is laid in layers between the seismic isolation unit and the concrete layer, the two plate members of the seismic isolation unit are interposed between the spherical bodies. Even when rolling or sliding relative to each other, even if the surface of the concrete layer has irregularities, the local load acting on the plate material is absorbed by compressive deformation of the uneven absorber due to compression and deformation. Can prevent the seismic isolation member from being damaged. Further, even if the concrete layer has irregularities, the seismic isolation structure can be formed without using a conventional self-leveling material, so that the construction is significantly simplified.

[Brief description of the drawings]

FIG. 1 is a sectional view partially showing an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view illustrating a state in which an external force such as an earthquake acts to perform seismic isolation movement in one embodiment of the present invention.

FIGS. 3A and 3B are a plan view and a side view of the seismic isolation unit during transportation or construction.

FIG. 4 is a sectional view schematically showing a conventional seismic isolation structure.

FIG. 5 is a sectional view schematically showing a conventional seismic isolation structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Seismic isolation structure 11 Solid foundation (upper structure) 12 Seismic isolation unit 12a, 12c Plate 12b Spherical body 13 Irregular absorption material (expanded polystyrene plate) 14 Concrete plate (concrete layer)

Claims (1)

[Claims] 1. An uneven absorber arranged in a layer on a concrete layer, a plurality of seismic isolation units laid on the uneven absorber, and an upper structure provided on the seismic isolation unit And wherein the seismic isolation unit comprises a plurality of spherical bodies inserted between two plate members.