JP2658024B2 - Seismic isolation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a seismic isolation device for preventing seismic force from being transmitted to equipment, structures, and the like, and in particular, combines a seismic isolation effect and a damping effect. It relates to an improved seismic isolation device.

[Prior art] A structure (seismic isolation rubber) in which a plurality of steel plates and rubber plates are alternately laminated is used as a support member that satisfies the anti-vibration properties during an earthquake.
It has been receiving attention recently.

When such seismic isolation rubber is interposed between a rigid building such as concrete and a foundation, it is soft in the lateral direction, that is, the shear rigidity is small. It has the effect of shifting, and the acceleration received by the building due to the earthquake becomes very small.

A major feature of such seismic isolation rubber is that it undergoes elastic deformation that returns to its original position after deformation due to the earthquake, and furthermore, in order to minimize the settlement of the building due to the creep phenomenon of the seismic isolation rubber. In addition, the energy absorption capacity (damping effect) of the seismic isolation rubber itself is extremely small. For this reason, conventionally, the seismic isolation rubber is configured using a rubber material having a small hysteresis loss as a material characteristic.

However, with such a seismic isolation device using only low-damping seismic isolation rubber, the slow rolling of the building during an earthquake remains for a long time even after the earthquake has subsided. There is a danger that not only will the seismic isolation rubber earthquake be damaged, but also the collision between the building and other structures and the destruction of equipment such as water pipes, gas pipes, and wiring.

Therefore, conventionally, in order to reduce the roll displacement as soon as possible, a method of using a plastic damper made of a soft metal or the like which undergoes plastic deformation immediately when an earthquake force is applied has been adopted. For example, the interior of seismic isolation rubber is hollowed out, lead is embedded in this part, and the damping effect is given to the seismic isolation rubber by using plastic deformation during an earthquake, thereby combining the seismic isolation effect and the damper (damping effect). It has been proposed that this be done.

[Problems to be Solved by the Invention] However, in such a seismic isolation device, although the function of absorbing seismic energy is increased, a new coseismic phenomenon caused by the high elasticity of the plastic damper causes a high-frequency region. Appears in

In addition, in the case of seismic isolation rubber containing lead, when the seismic isolation rubber undergoes a large deformation during a large earthquake, the hard plate made of steel damages lead, and the damaged lead damages soft plates such as rubber. Easily breaks. Moreover, the damaged lead is easily broken by repeated large deformation.

Means for Solving the Problems The present invention solves the above-mentioned conventional problems, and provides an improved seismic isolation device having both a seismic isolation effect and a damping effect. A seismic isolation device in which a seismic isolation rubber in which a hard plate having a soft plate having a viscoelastic property and a soft plate having a viscoelastic property are alternately provided, and a damper made of plastic are provided in parallel. A seismic isolation device characterized by satisfying (1) to (4) and being composed of the following materials.

Elastic modulus (longitudinal modulus) at 25 ° C is 1 to 10 ³ kg / mm
^{2 The} elongation at break at 25 ° C is 50% or more. The hysteresis ratio (h ₅₀ ) at 25 ° C and 50% tensile deformation is
0.3 or more polystyrene, polyethylene, polypropylene, AB
S, one or two or more selected from the group consisting of polyvinyl chloride, polymethyl methacrylate, polycarbonate, polyacetal, nylon, chlorinated polyether, and rubber-modified products of these resins. The constituent plastic satisfies the above-mentioned characteristics and is made of the above-mentioned specific material, so that it has an extremely large damping effect. Further, the seismic isolation rubber in which a plurality of hard plates and soft plates are alternately bonded has an excellent seismic isolation effect and an excellent damping effect.

Therefore, according to the seismic isolation device of the present invention in which such a plastic damper and seismic isolation rubber are arranged in parallel, the shaking transmitted to the building is reduced, and the building can be stably supported for a long period of time with good stability. Become.

Embodiment An embodiment will be described below with reference to the drawings.

1 and 2 are longitudinal sectional views each showing a seismic isolation device according to an embodiment of the present invention.

As shown in FIG. 1, the seismic isolation device of the present invention comprises a seismic isolation rubber 1 in which a plurality of rigid plates 11 having rigidity and a soft plate 12 having viscoelastic properties are alternately bonded, and plastic. The damper 2 is provided in parallel.
In the figures, reference numerals 13 to 16 denote flanges, 20 denotes a building, and 30 denotes a foundation.

In the seismic isolation device of the present invention, the damper 2 may have any shape as long as the energy loss at the time of its shearing deformation or bending deformation can be used favorably as a damping effect, and is not restricted in terms of shape. Is suitable for the column.

Further, in the present invention, the plastic damper 2 is used in combination with the seismic isolation rubber 1, and the arrangement of the two is such that the seismic isolation rubber 1 and the damper 2 are connected to the building 20 and the foundation 30 as shown in FIG. The center of the seismic isolation rubber 1 may be hollowed out to provide a cylindrical space, and the plastic damper 2 may be sealed in this space, as shown in FIG. . (Note that in FIG. 2,
The same members as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. In addition, the ratio of the number of arrangements and the arrangement interval of the seismic isolation rubber 1 and the damper 2 in the seismic isolation device shown in FIG. The area ratio and the like are appropriately selected according to the purpose of use of the seismic isolation device.

Hereinafter, the configuration of each of the seismic isolation rubber 1 and the damper 2 will be described.

As a plastic constituting the damper of the present invention,
From the viewpoint of the damping effect, a material satisfying the following physical properties is used.

Elastic modulus (longitudinal modulus) at 25 ° C is 1 to 10 ³ kg / mm
^2. More preferably, the elongation at break at 1-5 × 10 ² kg / mm ^{2 at} 25 ° C. is 50% or more, more preferably 70% or more, and the hysteresis ratio (h ₅₀ ) at 50 ° C. and 50% tensile deformation is 50%.
0.3 or more, more preferably 0.4 or more In the present invention, as the plastic of the damper material, polystyrene, polyethylene, polypropylene, AB
S, polyvinyl chloride, polymethyl methacrylate, polycarbonate, polyacetal, nylon, thermoplastic resins such as chlorinated polyethers, and one or more of the group consisting of rubber modified products of these resins, and further these resins As plasticizers, phthalic acid, isophthalic acid, adipic acid, tetrahydrophthalic acid, sebacic acid, azelaic acid, maleic acid, fumaric acid, trimellitic acid, citric acid, itaconic acid, oleic acid, ricinoleic acid, stearic acid, phosphoric acid, Various acid derivatives such as sulfonic acid and the like to which various derivatives of glycol, glycerin, paraffin and epoxy are added are used.

These plastics may be used alone or as a blend of two or more. Also, if necessary,
Various fillers, tackifiers, lubricants, antioxidants, softeners,
A general compounding agent such as a low molecular weight polymer oil may be mixed.

Such a plastic damper may be coated with a different material such as various protective agents on its exposed surface in order to improve weather resistance and the like.

On the other hand, the material of the hard plate 11 of the seismic isolation rubber 1 is metal,
Ceramics, plastics, FRP, polyurethane,
Wood, paper board, slate board, decorative board and the like can be used. As the soft plate 12, various kinds of vulcanized rubber, unvulcanized rubber, organic materials such as plastics, foams thereof,
Various materials such as inorganic materials such as asphalt and clay, and mixed materials thereof can be used. These hard plates 11
And the shape of the soft plate 12 is circular, square, other, pentagonal,
It may be a polygon such as a hexagon.

Also, the seismic isolation rubber 1 can be improved by coating the outer surface with a rubber material having excellent weather resistance for the purpose of improving the weather resistance and the like.

In this case, as the covering rubber material, a rubber-like polymer having excellent weather resistance is desirable, for example, butyl rubber, acrylic rubber, polyurethane, silicone rubber, fluorine rubber, polysulfide rubber, ethylene propylene rubber (ERP and EPDM),
Hypalon, chlorinated polyethylene, ethylene vinyl acetate rubber, epichlorohydrin rubber, chloroprene rubber, and the like. Of these, butyl rubber, polyurethane, ethylene propylene rubber, hypalone, chlorinated polyethylene, ethylene vinyl acetate rubber, and chloroprene rubber are particularly effective from the viewpoint of weather resistance. Further, in consideration of the adhesiveness with the rubber constituting the soft plate, butyl rubber, ethylene propylene rubber, and chloroprene rubber are desirable, and particularly, ethylene propylene rubber is most preferably used.

These rubber materials may be used alone or as a blend of two or more. Further, it may be blended with a commercially available rubber, for example, a natural rubber, an isoprene rubber, a styrene-butadiene rubber, a butadiene rubber, a nitrile rubber or the like to improve elongation and other physical properties. Further, these rubber materials include various fillers, anti-aging agents, plasticizers, softeners,
A general compounding agent may be mixed with a rubber material such as oil.

In order to manufacture such a seismic isolation device of the present invention, first, hard plates and soft plates are alternately laminated and bonded by an adhesive or co-vulcanization to produce a seismic isolation rubber.

Further, a damper 2 is formed by molding a plastic by a conventional method, and the damper 2 is arranged in parallel with the seismic isolation rubber 1 to obtain a seismic isolation device as shown in FIG.

On the other hand, in order to manufacture the seismic isolation device shown in FIG. 2, the center of the vulcanized seismic isolation rubber 1 is cut out, and a preformed damper 2 is inserted into this portion, or the center of the preformed damper 2 is inserted. A method is adopted in which a hard plate and a soft plate material whose portions are hollowed out are alternately inserted and co-vulcanized.

[Effect of the Invention] Since the seismic isolation device of the present invention has a damping effect in addition to the seismic isolation effect, the shaking at the time of the earthquake is absorbed by the seismic isolation structure, and the degree of the shaking transmitted to the building is reduced. Is done. For this reason, even when a large earthquake occurs, it is possible to prevent the building from colliding with other structures and to break down equipment such as water pipes, gas pipes, and wiring.

It should be noted that the seismic isolation device of the present invention can sufficiently expect excellent effects such as vibration isolation (vibration prevention, vibration suppression) in addition to the seismic isolation effect.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a seismic isolation device according to one embodiment of the present invention, and FIG. 2 is a longitudinal sectional view showing a seismic isolation device according to another embodiment of the present invention. 1 ... seismic isolation rubber, 2 ... damper, 11 ... hard plate, 12 ... soft plate, 13, 14, 15, 16 ... flange.

Claims (1)

(57) [Claims] 1. A seismic isolation rubber in which a plurality of rigid plates having rigidity and soft plates having viscoelastic properties are alternately bonded to each other, and a damper made of plastic is provided in parallel. A seismic isolation device, characterized in that the plastic satisfies the following and is made of the following materials. Elastic modulus (longitudinal modulus) at 25 ° C is 1 to 10 ³ kg / mm
^{2 The} elongation at break at 25 ° C is 50% or more. The hysteresis ratio (h ₅₀ ) at 25 ° C and 50% tensile deformation is
0.3 or more polystyrene, polyethylene, polypropylene, AB
One or more selected from the group consisting of S, polyvinyl chloride, polymethyl methacrylate, polycarbonate, polyacetal, nylon, chlorinated polyether, and rubber modified products of these resins