JPH0784815B2 - Seismic isolation device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a seismic isolation device for preventing seismic force from being transmitted to devices and structures, and particularly has both seismic isolation effect and damping effect. The present invention 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 has recently attracted attention as a bearing member that satisfies the vibration damping property during an earthquake.

In this way, when the seismic isolation rubber is interposed between a rigid building such as concrete and the foundation, it is soft in the lateral direction, that is, the shear rigidity is small. It has a shifting effect, and the acceleration that a building receives due to an earthquake becomes extremely small.

The major feature of such seismic isolation rubber is that it elastically deforms back to its original position after deformation due to an earthquake, and in addition, it minimizes the settlement of the building due to the creep phenomenon of the seismic isolation rubber. Moreover, the energy absorption capacity (damping effect) of the seismic isolation rubber itself is extremely small. Therefore, conventionally, the seismic isolation rubber has been configured by using a rubber material having a small hysteresis loss as its material property.

However, with such a seismic isolation device that uses only low-damping seismic isolation rubber, the slow rolling of a building during an earthquake remains for a long time even after the earthquake has subsided, so if this amount of rolling is large, Not only the seismic isolation rubber itself may be damaged, but there is also the risk of collision with buildings and other structures and destruction of equipment such as water pipes, gas pipes, and wiring.

Therefore, in order to reduce the rolling displacement as quickly as possible, a method of using a plastic damper made of a soft metal or the like that immediately plastically deforms when an earthquake force is applied is used. For example, hollowing out the inside of the seismic isolation rubber, embedding lead in this part, and using plastic deformation at the time of earthquake to give a damping effect to the seismic isolation rubber, combine seismic isolation effect and damper (damping effect) It has been proposed to do so.

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

Moreover, the method of using the seismic isolation rubber and the damper together makes the facility work complicated and brings about a significant cost increase.

In the case of lead-containing seismic isolation rubber, when the seismic isolation rubber is largely deformed in the event of a large earthquake, the hard plate of the steel plate damages the lead, and the damaged lead damages the soft plate such as rubber. Easily breaks. Moreover, the damaged lead is easily broken by repeated large deformation.

As shown in FIG. 2 (a) (longitudinal sectional view) and (b) (sectional view taken along line BB in FIG. 2 (a)), the hard plate 11
A space is provided at the center of the seismic isolation rubber 1 in which the soft plate 12 and the soft plate 12 are alternately laminated, and a viscous body 2 such as liquid, rubber, or resin is enclosed in the space, so that the seismic isolation rubber 1 is internally damped. Those that give the effect have been applied (Japanese Patent Application No. 60-5608).
9). Since such a seismic isolation device is deformed as shown in FIG. 3 during an earthquake, the viscous body and the wall surface 5 at the time of deformation are deformed.
It is intended to obtain the damping effect by the diping effect due to the friction with.

However, in this case, since the contact area between the viscous body 2 that gives the damping effect and the wall surface 5 of the internal space is small, the obtained damping effect is also small. Therefore, the enclosed viscous body is the damper of the seismic isolation device. I couldn't do my part. Reference numerals 3 and 4 in FIG. 2 indicate flanges.

[Means for Solving Problems] In order to solve the above problems, the seismic isolation apparatus of the present invention is configured such that a plurality of rigid hard plates and soft plates having viscoelastic properties are alternately laminated. By providing a cylindrical space in the center of the seismic isolation rubber, and by enclosing the solid material together with the viscous body in the cylindrical space so that the viscous body fills the gaps other than the solid material in the space. , Configured to combine the seismic isolation effect and the damping effect by utilizing the damping effect resulting from the frictional force during the shear deformation between the viscous body and the solid substance generated by the shear deformation of the seismic isolation rubber during an earthquake Is.

[Operation] In the seismic isolation device as shown in FIG. 2, the present inventors have earnestly studied to develop the maximum shear deformation effect from the viscous body, and as a result, increase the contact area with the viscous body, that is, By enclosing a solid substance capable of providing a contact area with the viscous body in the internal space, a contact surface with the viscous body is provided not only on the inner space wall surface but also on the solid substance surface, The inventors have completed the present invention by finding that the total contact area can be increased.

In the present invention, the viscous body enclosed in the cylindrical space provided in the center of the seismic isolation rubber contacts not only the wall surface of the cylindrical space but also the surface of the solid substance enclosed together with the viscous body. For this reason, the contact area between the viscous body that exhibits the damping effect and the solid is significantly increased, and an extremely large damping effect can be obtained.

Moreover, since the contact between the viscous body and the solid substance can occur in any direction, it is possible to exhibit a damping effect without anisotropy regardless of the direction of shear deformation caused by an earthquake. .

Therefore, according to the seismic isolation device of the present invention, the sway transmitted to the building is alleviated, and the building can be supported stably and reliably for a long period of time.

Embodiments Embodiments will be described below with reference to the drawings.

FIG. 1 is a vertical sectional view showing a seismic isolation device 10 according to an embodiment of the present invention.

As shown in the figure, the seismic isolation device 10 of the present invention has a cylindrical shape at the center of a seismic isolation rubber 1 in which a plurality of rigid hard plates 11 and soft plates 12 having viscoelastic properties are alternately laminated. A space is provided, and a solid substance such as the viscous body 2 and the spherical body 5 is enclosed in this cylindrical space. Reference numerals 3 and 4 are flanges.

In the present invention, the size of the cylindrical space provided in the seismic isolation rubber 1 is appropriately determined according to the purpose of use of the seismic isolation device, but in general, the cross-sectional area A of the cylindrical space and the cylindrical space The ratio A / B with the cross-sectional area B of the seismic isolation rubber containing More preferably It is preferable that

The solid substance sealed in this cylindrical space may be any solid substance that increases the contact area with the viscous body 2, and is, for example, a spherical body 5 as shown in FIG.

In this case, the shape of the spherical body 5 does not necessarily have to be a true sphere, and may be almost spherical. Further, the size does not necessarily have to be uniform, and in some cases, it may be better to have an appropriate particle size distribution as needed.

The diameter (or average diameter) D of the spherical body 5 varies depending on the scale of the seismic isolation device and the material of the spherical body 5 and the viscous body 2, but is usually 0.1 ≦ D ≦ 10 (mm), preferably 1 ≦ D ≦ 10. (Mm) is preferable.

Furthermore, the volume of the viscous body 2 enclosed in the cylindrical space is
When V _L and the volume of the spherical body 5 are V _R , Preferably The viscous body 2 and the spherical body 5 are preferably enclosed so that

As the solid substance, as shown in FIG. 4, a columnar body 6 having a circular cross section can also be adopted. Alternatively, a solid substance having a spheroidal shape, a flattened spherical shape, or the like can be used.

The solid substance such as the spherical body 5 and the columnar body 6 is preferably enclosed in a viscous body in a uniformly dispersed state, and may have a hollow interior for adjusting the specific gravity.

The solid substance may serve as a wall that increases the contact area with the viscous body, that is, a partition member that partitions the inside of the cylindrical space to form cells.

In this case, as the partition member, as shown in FIGS. 5A to 5E, it is preferable to form a group of elongated cells in the vertical direction in the cylindrical space of the base isolation rubber. Fifth
(A)-(e) is a perspective view which shows the example of the partition member provided in a cylindrical space, (a) is concentric, (b) is radial, (c) is (a) and (b). ), (D) is cylindrical, and (e) is spirally provided with the partition member 8. 5 (a) to 5 (e), the outermost cylinder indicates the inner wall of the cylindrical space of the base isolation rubber.

A honeycomb-shaped member or the like can be used as the partition member, but a member that is symmetrical with respect to the central axis of the cylindrical space is preferable because the stress during an earthquake is made uniform.

It is desirable that the partition member of FIGS. 5 (a) to 5 (e) is fixed to the seismic isolation rubber or the flange, but it is in contact with the end contacting the flange or the inner wall of the cylindrical space of the seismic isolation rubber. It is not always necessary to fix all the end portions to be fixed. For example, in the case of FIG. 5 (a), some partition members are fixed only on the upper end side, and some partition members are fixed only on the lower end side. Alternatively, the fixed portions may be changed alternately.

The partition member may be disk-shaped as shown in FIG. 5 (f). In this case, the disc-shaped partitioning members 8 are arranged at intervals with their disc surfaces orthogonal to the axial direction of the cylindrical space, and a viscous body is interposed between the disc-shaped partitioning members 8. In this case, the spacing d between the partition members 8 and the diameter D thereof are determined by the soft plate 12 which the main body portion of the seismic isolation device forms.
It is preferable that D / d is larger than T / t with respect to the thickness t and the diameter T thereof.

The material of the solid substance such as the spherical body, the columnar body or the cell forming partition member is not particularly limited, but for example, metal, ceramics, glass, FRP, plastics, polyurethane, high hardness rubber, wood, rock, gravel. Etc. are suitable. In addition to these materials, a rubber material having relatively low hardness, paper, leather, or the like can be used for the partition member.

As a rubber material, ethylene propylene rubber (EPR, EPD
M), nitrile rubber (NBR), butyl rubber, halogenated butyl rubber, chloroprene rubber (CR), natural rubber (NR),
Isoprene rubber (IR), styrene butadiene rubber (SB
R), butadiene rubber (BR), acrylic rubber, polyurene, silicone rubber, fluororubber, polysulfide rubber, hypalon, ethylene vinyl acetate rubber, epichlorohydrin rubber, etc. are suitable. Even if these rubber materials are used alone,
You may blend and use 2 or more types. Further, these rubber materials may be mixed with various fillers, antioxidants, plasticizers, softeners, oils and the like, which are generally compounding agents for rubber materials.

Plastics include polystyrene, polyethylene,
Thermoplastics such as polypropylene, ABS, polyvinyl chloride, polymethylmethacrylate, polycarbonate, boriacetal, nylon, chlorinated polyether, polytetrafluoroethylene, acetyl cellulose, ethyl cellulose, and also phenol resin, urea resin, Thermosetting plastics such as saturated polyester, epoxy resin, alkyd resin and melamine resin are suitable.

As the FRP, FRP obtained by reinforcing the above-mentioned rubber or plastic with various fibers or filler is also suitable.

The solid substance does not necessarily have to be composed of one type of material, but may be made by combining some of the above materials. For example, metal and rubber or plastic and rubber may be used in combination.

On the other hand, as the viscous substance to be enclosed in the cylindrical space, mineral oil type softening agents such as aroma oil, naphthenic oil, paraffin type oil; castor oil, cottonseed oil, linseed oil, rapeseed oil, soybean oil, palm oil, Vegetable oil softeners such as coconut oil, peanut oil, rosin and pine oil; low molecular weight oils such as silicone oil are preferred.

Further, as a plasticizer, 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, Examples thereof include various acid derivatives such as phosphoric acid and sulfonic acid; various derivatives of glycol, glycerin, paraffin and epoxy, and polymerization plasticizers. Bitumen and the like are also suitable. These viscous materials can be used alone,
You may blend and use multiple types.

An appropriate filler may be mixed with these viscous materials for the purpose of further improving the damping effect. Examples of effective fillers include clay, diatomaceous earth carbon black, silica, talc, barium sulfate, carbon calcium, carbon magnesium, metal oxides, mica, graphite, aluminum hydroxide, and other scale-like inorganic fillers, and various metals. Powder, wood chips, glass powder, ceramic powder, granular or powder-like solid filler such as granular or powder polymer, other various natural or artificial single fibers, long fibers (for example, straw, hair, glass fiber, metal fiber, Other various polymer fibers and the like) can be mentioned.

It is also possible to increase the viscosity of the viscous body by adding an adhesion-imparting agent to further improve the damping effect. Examples of the tackifier include coumarone resin, phenol, terpene resin, petroleum hydrocarbon resin, rosin derivative and the like.

In addition, as the viscous material, plasticized plastics obtained by mixing a thermoplastic rubber, which will be described later, as a high-hysteresis rubber material with a plasticizer, an oil filler, and the like, and an agar-like inorganic or organic gel body are also effective.

When a partition member is provided as the solid substance as shown in FIGS. 5A to 5F, it is effective to use a rubber material having a high hysteresis loss as the viscous body. High-hysteresis rubber materials include ethylene propylene rubber (EPR, EPDM), nitrile rubber (NBR), butyl rubber, halogenated butyl rubber, chloroprene rubber (C
R), natural rubber (NR), isoprene rubber (IR), styrene-butadiene rubber (SBR), butadiene rubber (BR), etc., to 100 parts by weight of a rubber composed of one or more kinds, cyclopentadiene resin or A vulcanized mixture of 15 to 100 parts by weight of dicyclopentadiene resin is suitable.

It is extremely effective to mix various anti-aging agents, antioxidants, anti-ozonants, stabilizers, flame retardants, etc. into the above viscous materials in order to suppress changes in their physical properties even after a long period of time. is there.

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 adhesive or co-vulcanization to produce a seismic isolation rubber. In the present invention, as the material of the hard plate, metal, ceramics, plastics, FRP, polyurethane, wood, paper plate, slate plate, decorative plate and the like can be used. As the soft plate, various materials such as various vulcanized rubbers, unvulcanized rubbers, organic materials such as plastics, foams thereof, inorganic materials such as asphalt and clay, and mixed materials thereof can be used. . The shapes of the hard plate and the soft plate may be circular, rectangular, or polygonal such as pentagon and hexagon.

Next, a cylindrical space is formed in the center of the produced base isolation rubber, and a viscous body and a solid substance are enclosed in this space. At this time, if a ring-shaped hard plate and a soft plate, which are preliminarily opened at the center, are laminated, the cylindrical space forming step can be omitted.

In order to enclose the viscous body and the solid substance in the cylindrical space of the seismic isolation rubber, these may be enclosed directly in the cylindrical space, but generation of metal rust due to corrosion of the hard plate by the viscous body,
Based on that, in consideration of the adhesion separation of the soft plate-hard plate of the seismic isolation rubber, and the possibility of leakage of the viscous body to the outside, etc., the viscous body and the solid substance were enclosed independently of the seismic isolation rubber body. It is desirable to make a special pack and insert this pack into the cylindrical space.

That is, when manufacturing the seismic isolation rubber 1, one flange 3
6, a female screw hole 9 as shown in FIG. 6 is provided, a plug 9a to be screwed into the screw hole 9 is prepared, and a pack 13 containing a viscous substance and a solid substance is inserted, and then the plug 9a is inserted. Seal with.
The pack 13 may be fixed to the inner wall of the cylindrical space or the flange, or may simply be inserted.

The material forming the pack 13 is not particularly limited, but may be rubber, polyurethane, plastic, ERP,
Examples include paper, leather and metal plates. As the rubber material, plastic, and FRP, those exemplified as the material of the above solid substance can be adopted.

The pack 13 does not necessarily have to be made of one type of material, and some of these materials can be combined. For example, metal and rubber, plastic and rubber, etc. may be combined.

As described above, when the seismic isolation rubber main body and the pack are manufactured independently, it is possible to manufacture them much more easily than when they are integrally manufactured, and the cost can be reduced. Moreover, in this case, it is possible to replace only the pack or only the seismic isolation rubber.

[Effects of the Invention] As described in detail above, the seismic isolation device of the present invention has both a seismic isolation effect and a damper effect. Therefore, the seismic vibration at the occurrence of an earthquake is absorbed by the seismic isolation structure and is transmitted to the building. The degree is reduced. Therefore, even when a large earthquake occurs, it is possible to prevent the building from colliding with other structures and the damage of equipment such as water pipes, gas pipes, and wiring.

In addition to the seismic isolation effect, the seismic isolation device of the present invention can sufficiently expect excellent effects such as vibration isolation (vibration suppression and vibration suppression).

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing a seismic isolation device according to an embodiment of the present invention, FIGS. 2 (a) and 2 (b) are conventional seismic isolation devices, and FIG. 2 (a) is a longitudinal sectional view. FIG. 2 (b) is a cross-sectional view taken along the line BB of FIG. 2 (a). FIG. 3 is a vertical cross-sectional view showing the seismic isolation device shown in FIGS. 2 (a) and 2 (b) when it is deformed. FIG. 4 is a longitudinal sectional view showing a seismic isolation device according to another embodiment of the present invention. 5 (a) to 5 (e) are, respectively,
FIG. 5F is a perspective view showing an example of a partition member that can be adopted in the seismic isolation device of the present invention, and FIG. FIG. 6 is a vertical sectional view for explaining an example of manufacturing the seismic isolation device of the present invention. 1 ... seismic isolation rubber, 2 ... viscous body, 3,4 ... flange, 5 ... spherical body, 6 ... columnar body, 8 ... partitioning member, 10 ... seismic isolation device, 11 ... hard plate , 12 …… Soft plate, 13 …… Pack.

Claims (5)

[Claims] 1. A seismic isolation device in which a plurality of hard plates having rigidity and soft plates having viscoelastic properties are alternately laminated to each other, and a cylindrical space is provided at the center of the seismic isolation device. A seismic isolation device enclosing a viscous body and a solid substance, wherein the viscous body is enclosed so as to fill a gap portion other than the solid substance in the space. 2. The seismic isolation device according to claim 1, wherein the solid substance is a partition member that partitions the inside of the cylindrical space to form cells. 3. The seismic isolation device according to claim 1, wherein the solid substance is a spherical body. 4. The seismic isolation device according to claim 1, wherein the solid substance is a columnar body. 5. The solid substance is disk-shaped, and a plurality of solid substances are arranged with the disc surface direction perpendicular to the axial center direction of the cylindrical space. The seismic isolation device described.