JP2000346125A - Base isolation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a base isolation device with excellent damping effect for vibration in an earthquake and with excellent installation workability, and damping effect for micro-vibration such as traffic vibration. SOLUTION: A lower side-supporting body 4 on the upper face with a friction plate 20 adhesive bonded, is fixed on the ground 12, and vibration is damped by frictional sliding of a friction plate 22 on the undersurface of an upper side- supporting body 18 fixed to the lower side of a member 16 to be supported, and the friction plate 20. Further, a cushion rubber 24 is provided on the upper side-supporting body 18, and the upper side-supporting body 18 and the cushion rubber 24 are surrounded by a surrounding member 26. Gaps d1, d2 of 0.1 to 5 mm are provided between the surrounding member 26 and the upper side- supporting body 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seismic isolation device for attenuating vibration during an earthquake to prevent the propagation of the vibration to a building or the like, and more particularly to a seismic isolation device having an excellent effect of attenuating minute vibration. .

[0002]

2. Description of the Related Art Conventionally, in order to protect a building from an earthquake, a plurality of hard plates having rigidity such as steel plates and a plurality of soft plates such as rubber having viscoelastic properties are alternately laminated. A seismic isolation rubber having a composite laminate as a component is used.

[0003] Generally, this seismic isolation rubber is provided alongside a damper. By supporting the building with the seismic isolation rubber, the natural frequency of the building is made longer, the resonance with seismic waves is prevented, and the amplitude is reduced. Has a large but slow vibration, and a seismic isolation system is adopted, in which the vibration is converged in a short time by the damper provided. Here, examples of the damper to be provided include a metal rigid rod damper, a friction damper, a viscous damper, and the like. As one type of such a damper, a slider-type friction damper that utilizes a frictional force generated between two friction plates (hereinafter, referred to as a “slider”).
There is.

The present applicant has previously proposed a slider having a configuration as shown in FIG. 2 so that such a slider can be easily attached to a supported member such as a building.
0-180784. Hereinafter, it is referred to as “first application”. ).

The slider shown in FIG. 2 includes a lower support 14 attached to a ground (foundation) 12 on which a structure is disposed, a structure as a supported member, or a support substrate 16 for the structure.
The upper support 18 attached to the is configured to be relatively freely displaceable in the lateral direction only when a lateral force equal to or more than a predetermined value is input, and at the contact surface between the tips of the upper support and the lower support, Vibration is attenuated by utilizing sliding friction between friction plates arranged on respective surfaces.

The upper surface of the lower support 14 and the upper support 18
The friction plates 20 of the upper support 18 are provided on the lower surface of the lower support 14, respectively.
Slidably in contact with This friction plate 20,
Reference numeral 22 denotes a metal plate 20A, 2 on the support body 14, 18 side.
2A and the synthetic resin coatings 20B and 22B formed on the surfaces (sliding surface side) of the metal plates 20A and 22A.

The upper support 18 has a columnar main body 18A and a flange 18B projecting laterally above the main body 18A. A rubber layer (hereinafter, referred to as “cushion rubber”) 24 is provided between them.

A surrounding member 26 is provided so as to surround the cushion rubber 24 and the upper flange portion 18B of the upper support 18. The surrounding member 26 includes a side peripheral portion 26A surrounding the flange portion 18B of the upper support 18 and the cushion rubber 24, and a portion extending from a lower end portion of the side peripheral portion 26A below the flange portion 18B of the upper support 18. An inward flange portion 26B having an outwardly facing flange portion 26B and an outwardly extending flange portion 26C which projects outward from the upper end of the side peripheral portion 26A.
6B engages the flange portion 18B of the upper support 18 to support it, and the outward flange 26C is fixed to the structure or its support substrate 16 to attach the slider.

In this slider, the main body 18A of the upper support 18 is columnar, while the lower support 14 is provided on the lower surface of the upper support 18 so that it can be stably disposed on the ground 12. It is a flat plate having an area larger than that of the friction plate 22.

The lower support 14 and the friction plate 20 are firmly fixed by an adhesive or bolts, and the upper support 18 and the friction plate 22 are firmly fixed by an adhesive or fitting. Support 18 and cushion rubber 2
4, and the cushion rubber 24 and the structure or its supporting substrate 16 are not fixed.

The cushion rubber 24 absorbs a slight deviation of the parallelism between the upper and lower surfaces of the upper and lower friction plates 20 and 22 due to its compressive deformation, and stabilizes the contact surface by keeping the two friction plates 20 and 22 parallel. Is provided.

To attach the slider, first, the lower support 14 to which the friction plate 20 is bonded or bolted is attached.
Is fixed to the ground 12 by locking means such as bolts 28. On the other hand, after attaching the upper support 18 to which the friction plate 22 is adhered and the cushion rubber 24 to the surrounding member 26, the surrounding member 2
6 is fixed to the structure or its supporting substrate 16 by a locking means such as a bolt 28.

When the friction plate 22 is disposed below the gravitational force, as in the case of the upper support 18, the structure or the support substrate 16 thereof is placed on the upper support 18 against the gravitational force. Considering that a strong shear force is applied in the lateral direction during an earthquake, etc., the vibration (displacement)
The upper support body 18 and the structure or its support substrate 16 that receive frictional force that can attenuate the surface of the building or the support substrate 16 have a problem of lacking reliability when fixed by a normal fixing method. By using the surrounding member 26, the fixing of the upper support 18 to the structure or the support substrate 16 becomes easy, and the stability thereof is remarkably improved.

[0014]

The slider of the prior application has an extremely excellent effect in terms of mountability and the like, but has a drawback that the effect of preventing the propagation of minute vibrations to the building is not sufficient.

The present invention is a seismic isolation device which prevents such drawbacks of the prior application slider, has an excellent vibration damping effect at the time of an earthquake, and has good installation workability. It is an object of the present invention to provide a seismic isolation device that is excellent in the effect of damping minute vibrations.

[0016]

According to the present invention, there is provided a seismic isolation device including a lower support, a lower friction plate provided on an upper surface of the lower support, and a lower side of a supported member. An upper support, a rubber layer interposed between the upper support and the supported member, and a lower surface of the upper support, which is slidably slidable on the upper surface of the lower friction plate. An upper friction member in contact therewith, and a surrounding member surrounding the upper portion of the upper support and the rubber layer, wherein the upper support is stretched laterally at a main body portion and an upper portion of the main body portion. The surrounding member extends vertically around the flange, and has an upper end fixed to the supported member; and A seismic isolation device having an inward flange projecting from a lower end to a lower side of the flange; 0.1 between the outer peripheral surface of the main body portion of which Ai gap of 0.1 to 5 mm, and the inner peripheral surface of the inner-facing flange portion and the upper support between the outer peripheral surface of the flange
A gap of about 5 mm is provided.

The slider of the prior application shown in FIG. 2 has a structure in which the inward flange 26B of the surrounding member 26 and the flange 18B of the upper support 18 are engaged without any gap. As a result, the cushion rubber 24 could not be deformed, and the propagation of minute vibration such as traffic vibration could not be prevented.

On the other hand, in the seismic isolation device of the present invention, between the inner peripheral surface of the side peripheral portion of the enclosing member and the outer peripheral surface of the flange portion of the upper support, and the inside of the inward flange portion of the enclosing member. 0.1 to 5 m between the peripheral surface and the outer peripheral surface of the main body of the upper support
Since the gap of m is provided, the cushion rubber (the rubber layer between the upper support and the supported member) can be deformed, and the vibration is attenuated by the deformation of the cushion rubber against minute displacement. Can be done.

That is, the dominant frequency of the constant vibration of the ground is 3H
z is exceeded. Therefore, in order to reduce the propagation of the minute vibration to the building, it is effective to set the natural frequency of the supported member in the minute vibration to 2.5 Hz or less. In the seismic isolation device of the present invention, the natural frequency of the supported member can be controlled to be such a frequency by displacing the cushion rubber in a minute displacement, and propagation of the minute vibration is prevented. .

In the present invention, there is a space between the upper surface of the inward flange of the surrounding member and the lower surface of the flange of the upper support.
Preferably, there is a gap of 1 mm or more.

A metal plate or a reinforcing cloth is adhered to the upper and lower surfaces of the rubber layer as the cushion rubber so that the rubber layer does not expand in the horizontal direction due to compression. The rubber hardness (JIS-A) of the rubber layer is preferably 30 to 70.

[0022]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of a seismic isolation device (slider) of the present invention.

The slider is provided between the inner peripheral surface of the side peripheral portion 26A of the enclosing member 26 and the outer peripheral surface of the flange portion 18B of the upper support member 18, and between the inner peripheral surface of the inward flange 26B of the enclosing member 26 and the upper side. Gaps d ₁ and d _{2 of} 0.1 to 5 mm are provided between the outer peripheral surface of the main body 18 </ b> A of the support 18 and the upper surface of the inward flange 26 </ b> B of the surrounding member 26 and the upper support 18. is 0.1mm or more gap d ₃ is provided between the lower surface of the flange portion 18B, also, the metal plate or reinforcing cloth 30A on the upper and lower surfaces of the cushion rubber 24, that 30B is bonded is, in FIG. 2 Different from the slider of the prior application shown in the drawings, the other components have the same configuration, and therefore, members having the same functions are denoted by the same reference numerals, and description thereof will be omitted.

In the present invention, the gaps d ₁ and d ₂ are 0.1 m
If it is less than m, it is difficult to avoid contact between the flange portion 18B of the upper support 18 and the side peripheral portion 26A of the surrounding member 26, and the flange portion 26B and the main body portion 18A during mounting. d ₁ ,
When d ₂ exceeds 5 mm, the seismic isolation effect at the time of an earthquake due to the provision of the surrounding member 26 is reduced. That is, when the structure or the supporting substrate 16 thereof is displaced in the horizontal direction by a predetermined amount or more, the inner surface of the surrounding member 26 comes into contact with the outer surface of the upper support 18, and the cushion rubber 24 is not further deformed. The upper support 18 is a structure or its support substrate 16.
Is moved horizontally together with the friction plate 22 of the upper support 18.
The vibration is attenuated by friction sliding between the lower support 14 and the friction plate 20, but if the gaps d ₁ and d ₂ are larger than 5 mm, the damping due to the frictional sliding is provided. The effect is less likely to be exhibited, and seismic isolation performance during an earthquake is reduced.

The gaps d ₁ and d ₂ are particularly preferably 0.1 to 3 mm.

[0027] In addition, it is less than the gap d ₃ 0.1mm, from the fact that handling during construction becomes difficult, the gap d ₃ 0.
It is preferably 1 mm or more. Since the gap d ₃ is deteriorated is attached workability excessively large, it is preferable gap d ₃ is particularly 0.1 to 10 mm.

In this slider, a metal plate or a reinforcing cloth 30 is provided on upper and lower surfaces which are pressure receiving surfaces of the cushion rubber 24.
A and 30B are provided to restrain the cushion rubber 24, so that the cushion rubber 24 can be easily designed to obtain a desired damping characteristic.

The rubber material constituting the cushion rubber 24 preferably has a rubber hardness (JIS-A) of 30 to 70. If the rubber hardness is less than 30, the creep increases, which is not preferable for use. On the other hand, if it exceeds 70, the rubber tends to be thick, and the handling in production and construction deteriorates.

The cushion rubber 24 is generally disk-shaped, and preferably has a diameter of 40 to 600 mm. If the diameter of the cushion rubber 24 is less than 40 mm, the area of the cushion plate 24 may be smaller than that of the friction plate 22 of the upper support 18.
The stabilizing effect of the contact surfaces 0, 22 cannot be sufficiently obtained,
If it exceeds 0 mm, the handling in production and construction will be poor. Further, the thickness of the cushion rubber 24 is preferably about 5 to 20 mm, though it varies depending on the rubber hardness.

The thickness of the metal plate or the reinforcing cloth 30A, 30B provided on the upper and lower surfaces of the cushion rubber 24 is 1 to 3
mm.

In the present invention, the synthetic resin material constituting the synthetic resin films 20B and 22B of the friction plates 20 and 22 may be polytetrafluoroethylene, polyamide imide, polyamide, polyimide, polyester, silicone resin, epoxy resin, polysulfone. And the like in which a low friction coefficient is achieved by mixing a heat-resistant resin material such as The resin material to be mixed with the polytetrafluoroethylene may be used alone or in combination of two or more. From the viewpoint of achieving both a low friction coefficient and strength, the resin material particularly contains polytetrafluoroethylene and a polyamideimide resin. Are preferred. When using a mixture of polytetrafluoroethylene and a polyamideimide resin, the content ratio (weight ratio) of both is preferably 0.5: 9.5 to 3: 7, and 0.75: 9.25 to 0.75: 9.25. The ratio is more preferably 2.75: 7.25, particularly preferably 1: 9 to 2.5: 7.5. When the content ratio of the polyamide-imide resin exceeds 9.5 and the content ratio of the polytetrafluoroethylene is less than 0.5, the friction coefficient becomes too large, and it is difficult to obtain desired performance. If the content is less than 3, and the content ratio of polytetrafluoroethylene exceeds 3, the resin strength is reduced, and the abrasion resistance is reduced. Further, a plasticizer or a filler may be added to the resin composition for forming the synthetic resin film, as long as it does not adversely affect the friction coefficient.
It may be a mixture of reinforcing materials such as P.

The thickness of the synthetic resin coatings 20B and 22B is preferably 10 to 100 μm. When the coating thickness is less than 10 μm, the coating strength becomes weak, which is not preferable in use, and when it exceeds 100 μm, the productivity decreases.

The metal plates 20A of the friction plates 20, 22
As the 22A, it is preferable to use a stainless steel plate in terms of corrosion resistance, durability, strength and the like, and the thickness of the metal plates 20A and 22A is usually about 1 to 6 mm.

The slider according to the present invention having the above-described structure is excellent in the reliability and stability of the upper structure of the upper support fixed to the supported member downward in the direction of gravity, and the fixing of the upper support to the supported member. Has good stability over time,
Since it has high durability, a seismic isolation system having both excellent durability and seismic isolation performance can be configured by combining with the above-mentioned seismic isolation rubber made of the composite laminate.

In the seismic isolation system, it is preferable to control the ratio of the weight supported by the entire slider to the total weight of the skeleton. 1.0 is preferred. Further, it is preferable to set a large initial rigidity for measures such as wind sway, and the amount of the slider required to obtain the minimum initial rigidity is such that the above-mentioned slider load sharing ratio P is at least 0.30 or more. It was confirmed that there was. Therefore,
From the viewpoint of the balance between the seismic isolation effect and the wind sway prevention effect,
Is preferably in the range of 0.30 ≦ P ≦ 1.0.

A problem with the slider is that when the upper surface is lifted by a negative pressure, the frictional force becomes zero and the slider does not function as a damper. Therefore, it is desirable to install the seismic isolation rubber having a large pull-out resistance in a place where negative pressure is likely to be generated. For this reason,
It is preferable to install a seismic isolation rubber at a location farthest from the fulcrum (center of gravity) where there is a concern of moving vertically, specifically, at the corners of the supported member including the four corners.

[0038]

EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to the following examples unless it exceeds the gist.

Example 1 A slider of the present invention shown in FIG. 1 was produced with the following specifications.

The friction plate 22 of the upper support 18 has a diameter of 60
Polytetrafluoroethylene and a polyamideimide resin are applied to a stainless steel plate 22A having a thickness of 1.5 mm and a thickness of 3 mm by 1.5:
The resin composition mixed at a weight ratio of 8.5 has a thickness of 2
It was produced by forming a synthetic resin film 22B of 0 μm. The friction plate 22 is made of iron and adheres to the lower surface of the upper support 18 having a diameter of 100 mm, a flange portion 18B in contact with the cushion rubber 24 having a diameter of 100 mm, a body portion 18A on which the friction plate 22 is provided having a diameter of 60 mm, and a height of 50 mm. Fixed.

As the friction plate 20 of the lower support 14, 6
00mm × 600mm, 3mm thick stainless steel plate 20
A synthetic resin film 20B having a thickness of 20 μm was formed on the surface of A by using a resin composition in which polytetrafluoroethylene and a polyamideimide resin were mixed at a weight ratio of 1.5: 8.5. The friction plate 20 is fixed to the surface of the lower support 14 made of iron by bonding with an adhesive.
Was firmly fixed to the foundation (ground) 12 with bolts 28.

As the cushion rubber 24, rubber hardness (J
IS-A) A disc-shaped rubber material having a diameter of 88 mm and a thickness of 10 mm made of a rubber material having the composition shown in Table 1 of 40 is used.
B was fixed with an adhesive.

[0043]

[Table 1]

The stainless steel plate 30B of the cushion rubber 24 to which the stainless steel plates 30A and 30B are adhered is disposed above the upper support 18, and this is disposed in the opening of the surrounding member 26. At the same time, the outward flange 26C of the surrounding member 26 was firmly fixed to the support substrate 16 with bolts 28.

The surrounding member 26 includes a side peripheral portion 26.
A is inner diameter 102mm, outer diameter 122mm, wall thickness 10mm
The inner diameter of the inward flange 26B is 62 mm and the thickness is 5 m.
m, the outer diameter of the outward flange 26C is 180 mm, and the thickness is 10
mm and a total height of 25 mm, and the gaps d ₁ and d ₂ are 1
mm, a gap d ₃ was set to be 1mm.

A performance test was performed on the slider under the following test conditions, and the results are shown in Table 2.

[Test conditions] Load: 41 kN Displacement: 0.5 mm Frequency: 3 Hz (sine wave)

[0048]

[Table 2]

[0049]

As described above in detail, according to the seismic isolation device of the present invention, the seismic isolation device has an excellent vibration damping effect at the time of an earthquake and has good installation workability. There is provided a seismic isolation device that is also excellent in the effect of attenuating minute vibrations.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a seismic isolation device (slider) of the present invention.

FIG. 2 is a sectional view showing an embodiment of a slider of the prior application.

[Explanation of symbols]

 12 Ground 14 Lower support 16 Construction or its support substrate 18 Upper support 20, 22 Friction plate 20A, 22A Metal plate 20B, 22B Synthetic resin coating 24 Cushion rubber 26 Surrounding member 30A, 30B Metal plate or reinforcing cloth

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F16F 15/04 F16F 15/04 A

Claims (6)

[Claims] 1. A lower support, a lower friction plate disposed on an upper surface of the lower support, an upper support disposed below a supported member, and the upper support and the cover A rubber layer interposed between the support member and an upper friction plate provided on a lower surface of the upper support member and slidably in contact with an upper surface of the lower friction plate; And an enclosing member surrounding the rubber layer.The upper support body has a main body and an upper flange of the main body, and has a flange extending laterally. A side peripheral portion surrounding the flange, extending vertically, and having an upper end fixed to the supported member, and projecting below the flange from a lower end of the side peripheral portion. A seismic isolation device having an inward flange and an inner peripheral surface of the side peripheral portion and an outer peripheral surface of the flange. .1
There is a gap of about 5 mm, and 0.1 to 5 m between the inner peripheral surface of the inward flange and the outer peripheral surface of the main body of the upper support.
A seismic isolation device characterized by a gap of m. 2. The seismic isolation device according to claim 1, wherein a gap of 0.1 mm or more is provided between an upper surface of the flange and a lower surface of the flange. 3. The lower friction plate according to claim 1, wherein the lower friction plate includes a metal plate and a synthetic resin film formed on an upper surface of the metal plate. A seismic isolation device comprising: a metal plate; and a synthetic resin film formed on a lower surface of the metal plate. 4. The outer peripheral member according to claim 1, wherein the surrounding member has an outward flange portion projecting outward from an upper end of the side peripheral portion. Is fixed to the supported member. 5. The seismic isolation device according to claim 1, wherein a metal plate or a reinforcing cloth is adhered to upper and lower surfaces of the rubber layer. 6. The rubber layer according to claim 1, wherein a rubber hardness (JIS-A) of the rubber layer is 30 to 70.
A seismic isolation device, characterized in that: