JPH11230261A - Base isolation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a base isolation device that effectively produces a base- isolating function even if the superstructure is light as in a dwelling house, and that is simple in constitution, small and light. SOLUTION: The base isolation device comprises a first plate member 1 coupled to a superstructure, a second plate member 2 coupled to foundations, a spherical roller 5 interposed between the first and second plate members 1 and 2 for rolling motion to support the first plate member 1 above the second plate member 2, and an elastic hollow bag 8 that keeps the roller 5 therein and connects the first and second plate members 1 and 2 elastically for deformation when the first plate member 1 moves horizontally relative to the second plate member 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a seismic isolation device which is provided between a superstructure such as a building and a foundation and suppresses the vibration of the superstructure due to an earthquake.

[0002]

2. Description of the Related Art Conventionally, as a seismic isolation device of this kind,
For example, as shown in FIG. 8, a seismic isolation bearing rubber type in which a rubber c made of natural rubber or the like and a steel plate d are alternately laminated between a circular upper plate a and a lower plate b connected to an upper structure and a foundation, respectively. Is well known. This one is
The vertical stiffness of the laminate supports the load of the upper structure, and against horizontal rolling during an earthquake, the shear deformation of the rubber c and the damping action of the iron or lead plug e provided at the center position in the horizontal direction It is designed to absorb displacement and force. In addition, there is a type in which a damping function is provided by a hydraulic mechanism instead of the plug e, and a type in which the rubber c is made to have a high attenuation so that the rubber c itself exerts a damper function. This seismic isolation rubber type seismic isolation device has a simple structure,
It is widely used because it is possible to easily predict the damping performance of seismic force in the design before construction, and the construction work and maintenance after construction are easy.

Further, as shown in, for example, JP-A-8-326352, a flexible structure is provided between a pair of upper and lower hard members, and the flexible structure is filled with a fluid member. It has been proposed to form a sub-compartment so as to suppress the shaking of the upper structure due to an earthquake with a simple configuration.

Further, in recent years, a seismic isolation device combining a slide mechanism such as a bearing and a damper mechanism without using rubber has been known. In this seismic isolation device, for example, two slide mechanisms are connected in a substantially cross shape. Thus, the upper structure can be freely moved in two horizontal directions with respect to the foundation, and a spring, an oil damper or the like is separately added to the slide mechanism to suppress the swing of the upper structure.

Further, as shown in, for example, Japanese Patent Application Laid-Open No. 9-4279, a steel ball is sandwiched from above and below by a parabolic circular steel plate support having a bottom at the center,
It has been proposed to suppress the roll of the upper structure by eliminating the seismic acceleration by the reaction force when the steel ball ascends the lower pan support.

[0006]

However, the above-mentioned conventional seismic isolation bearing rubber type exerts seismic isolation performance due to the shearing force and shear deformation of the laminated rubber layer, so that it cannot be used in the horizontal direction. In order to increase the movement distance by shaking, it is necessary to increase the number of layers and increase the height, and to increase the height and stably support the upper structure, it is necessary to increase the diameter Since the equipment becomes large,
Installation space can be secured and vertical load is 50 to 100 kg /
In fact, it is used only for large buildings such as large apartments and hospitals with a size of about ² cm2.

In addition, the former proposal example (Japanese Patent Laid-Open No. 8-32)
In the seismic isolation device disclosed in Japanese Patent No. 6352), the strength of the flexible structure for supporting the load from the upper structure decreases due to aging, and the height of the upper structure cannot be kept constant. There's a problem. In addition, it is difficult to provide a plurality of compartments inside for manufacturing.

[0008] In a seismic isolation device combining a slide mechanism and a damper mechanism without using rubber, the structure of the slide mechanism and the damper mechanism is required in order to function against seismic force from any direction. Has become very complicated, and the difficulty in designing prior to construction and high cost have become problems, and it has not been widely used.

Further, the latter proposed example (Japanese Patent Laid-Open No. 9-4)
In the seismic isolation device disclosed in Japanese Patent No. 279), there is a problem that the steel structure moves on the parabolic dish cradle in response to the roll due to the earthquake, so that the upper structure also moves in the vertical direction. In addition, since the mechanism for damping the vibration is based on gravity, the upper structure has a vibration behavior close to free vibration, and there is a problem that the vibration is not well controlled.

The present invention has been made in view of the above points, and an object of the present invention is to provide a conventional seismic isolation device which suppresses shaking of an upper structure due to an earthquake. Therefore, even if the upper structure is lightweight, such as a private house, it can be supported without displacement in the vertical direction, and the displacement and force in the horizontal direction can be effectively suppressed, and Another object of the present invention is to make the structure simple, small, and lightweight.

[0011]

In order to achieve the above object, according to the present invention, as a seismic isolation device, first and second plate members provided to face each other up and down, and the first and second plate members are provided. A spherical roller which is provided between the second plate members so as to be rollable and supports the plate member on the upper structure side with respect to the plate member on the base side; Are elastically connected to each other, and a hollow elastic bag body is provided which extends when one of the two plate members moves relative to the other in the horizontal direction.

More specifically, the invention of claim 1 is directed to a seismic isolation device which is provided between an upper structure and a foundation and suppresses shaking of the upper structure due to an earthquake.

And, they are provided vertically facing each other,
First and second plate members, one of which is connected to the upper structure and the other of which is connected to the foundation;
A spherical roller that is provided to be able to roll between the plate members and supports the plate member on the upper structure side with respect to the plate member on the foundation side; and a first and a second roller in a state in which the roller is held inside.
And a hollow elastic bag that extends when one of the two plate members moves horizontally relative to the other.

According to the above configuration, since the plate member on the upper structure side is supported by the roller with respect to the plate member on the base side, the height of the upper structure can be stably maintained unlike rubber support. Can be maintained. Then, when an earthquake occurs, the plate member on the upper structure side moves in the horizontal direction relatively to the plate member on the foundation side due to the rolling of the rollers.
At this time, the elastic bag body is extended to generate a restoring force for returning the plate member on the upper structure side to the position before the movement, and this restoring force acts as a damping force together with the rolling friction force acting on the roller. . In addition, the larger the relative movement amount of the two plate members and the larger the amount of extension of the elastic bag, the stronger the elastic bag tends to adhere to the roller, so that the rolling frictional force of the roller increases. Therefore, the swing of the upper structure can be smoothly suppressed without moving the upper structure up and down, and after the convergence of the earthquake, the plate member or the upper structure on the upper structure side can be returned to the position before the movement. . Further, since the restoring force of the elastic bag and the rolling frictional force of the roller can be adjusted, they can be set to be optimal values according to the weight of the upper structure. In addition, the rollers and the bladder can function similarly for seismic forces from any direction.

According to a second aspect of the present invention, in the first aspect of the present invention, the elastic bag is made of a rubber member, and comes into contact with the outer periphery of the roller at a substantially vertical center between the first and second plate members. Shall be covered.

[0016] By doing so, the elastic bag can be made rich in elasticity and stress can be easily adjusted, and the roller can be reliably held. Also,
The area of the joint between the elastic bag and the first and second plate members can be increased, and the joining can be made reliable and strong.

According to a third aspect of the present invention, in the first or second aspect, the elastic bag is filled with an attenuating agent made of a liquid viscous material or a powdery or granular polymer material. I do.

According to the present invention, seismic energy can be more effectively attenuated, and the damping force can be adjusted by the material and amount of the damping agent. In addition, even in the case of a small earthquake or wind pressure during a typhoon, careless shaking of the upper structure can be suppressed by the resistance of the damping agent.

According to the fourth aspect of the present invention, the first, second or third aspect of the present invention is provided.
In the invention of (1), it is assumed that a stopper for restricting the rolling of the roller is provided on the entire periphery of at least one of the first and second plate members.

With this, even if an earthquake with a seismic intensity larger than expected occurs, it is possible to restrict excessive relative movement of the first and second plate members by bringing the rollers into contact with the stopper. It is possible to reliably prevent the roller from coming off the first or second plate member. Therefore,
The safety of the seismic isolation device against large earthquakes can be ensured.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show a seismic isolation device A according to an embodiment of the present invention. The seismic isolation device A is provided between a superstructure and a foundation of a building, and is particularly used in a private house or the like. This is applied when the superstructure is lightweight. The seismic isolation device A includes a first plate member 1 connected to the upper structure, and a second plate provided below and opposed to the first plate member 1 and connected to the foundation. Member 2;
A spherical roller 5 that is provided between the first and second plate members 1 and 2 so as to be rollable and supports the first plate member 1 with respect to the second plate member 2; And a hollow elastic bag body 8 having a barrel shape that is housed and held inside and covers the outer periphery of the roller 5. This elastic bag 8
The first and second plate members 1 and 2 are made of a rubber member.
It is in contact with the outer periphery of the roller 5 at substantially the center in the vertical direction between
The upper and lower ends are joined to the center of the opposing surfaces of the two plate members 1 and 2. The elastic bag 8 extends when the first plate member 1 moves in the horizontal direction relative to the second plate member 2 and returns the first plate member 1 to the position before the movement. A restoring force is generated.

A gap between the inside of the elastic bag 8 and the roller 5 is filled with a damping agent made of a liquid viscous material or a powdery or granular polymer material as required.

When the seismic isolation device A having the above-described structure is provided between a column or the like of a lightweight upper structure and a foundation, the load is supported by the rollers 5 positioned and accommodated in the elastic bag 8. As a result, the upper structure can be stably supported, and there is almost no aging in the vertical direction. The upper and lower ends of the elastic bag 8 are interposed between the roller 5 and the first and second plate members 1 and 2 to support the first plate member 1. Even if both ends are aged, it hardly affects the height of the superstructure. Further, the movement of the first plate member 1 can be prevented by the elongation stress of the elastic bag body 8 and the frictional resistance with the roller 5 against a small earthquake motion or wind pressure during a typhoon. Further, when the gap between the elastic bag 8 and the roller 5 is filled with an attenuating agent, such an unintentional swing of the upper structure can be more effectively suppressed.

When an earthquake occurs, the first plate member 1 moves relative to the second plate member 2 in the horizontal direction due to the rolling of the rollers 5. At this time, as shown in FIG. 3, the elastic bag 8 is deformed and expanded in the direction in which the first plate member 1 moves, and at the same time, a restoring force for returning the first plate member 1 to the position before the movement is generated. I do. Further, when the roller 5 rolls in the elastic bag body 8, resistance occurs due to friction between the two.
Moreover, the larger the relative movement amount of the two plate members 1 and 2 and the larger the amount of extension of the elastic bag 8, the more the inner surface of the elastic bag 8
, The frictional resistance increases. As a result of this resistance attenuating horizontal vibrations, it is possible to support the upper structure without moving it up and down, suppress its shaking, and prevent the object installed inside the building from falling down. After the convergence of the earthquake, the first plate member 1 or the upper structure can be returned to the position before the movement. Further, the restoring force of the elastic bag 8 can be adjusted by changing the configuration, material, thickness, etc. of the elastic bag 8. Also,
The degree of attenuation of the horizontal shaking depends on the configuration of the elastic bag body 8,
It can be adjusted by changing the material and thickness, the material and surface roughness of the roller 5, and the like. Since the elastic bag 8 and the roller 5 have no directionality, the elastic bag 8 and the roller 5 exhibit the same damping property and restoring property with respect to horizontal movement in any direction.

As a safety measure against an earthquake with a seismic intensity larger than expected, as shown in FIG. 4, at least one of the first and second plate members 1 and 2 (the second plate member 2 in FIG. 4). It is preferable to provide a stopper wall 12 for restricting the rolling of the roller 5 on the entire periphery of the peripheral edge of the roller 5). As a result, the roller 5 can be prevented from coming off the two plate members 1 and 2, and excessive relative movement of the two plate members 1 and 2 can be prevented, and the safety against an earthquake with a large seismic intensity can be improved. Can be secured. In addition, it is preferable to perform R chamfering or C chamfering on the inner peripheral corner of the stopper wall 12 (R chamfering is performed in FIG. 4).

The elastic bag 8 is usually made of rubber (natural rubber,
Although it is formed in a barrel shape covering the outer periphery of the roller 5 with a synthetic rubber) or a composite of rubber and fiber, it may be cylindrical as shown in FIG. The roller 5 is opened only at both ends, and the roller 5 is
2 may be directly contacted.

Further, in the above-described embodiment, only one roller 5 is held inside the elastic bag body 8. However, a plurality of rollers 5, 5,... The first plate member 1 may be supported on the second plate member 2. In this case, the rollers 5, 5,
Are arranged at substantially equal intervals on the same circumference so that the load of the superstructure is applied to the center between the rollers 5, 5,.

In the above embodiment, the upper and lower ends of the elastic bag 8 are adhered to the opposing surfaces of the first and second plate members 1 and 2, but may be joined by bolts or screws or the like. The joining and the bonding may be used in combination.

The first and second plate members 1 and 2 are usually made of circular steel, but may be made of a highly rigid material such as reinforced plastic or polygonal. The present invention can be applied.

[0030]

Next, a specific embodiment will be described. Four seismic isolation devices A are manufactured in the same manner as in the above embodiment, and each of the seismic isolation devices A is connected to each pillar 22 located at the four corners of a private house (upper structure 21) as shown in FIG. It was provided between each base 22 corresponding to each pillar 22 (only one pillar 22 is shown in FIG. 6). Each of these basics 2
Numeral 3 is placed on a plurality of rollers (not shown) for the test, and it is possible to apply vibration to each of the foundations 23 in the horizontal direction and shake them. Here, the horizontal spring constant of each of the seismic isolation devices A is 45 kgf / cm,
The horizontal damping coefficient was 34 kgf · s / cm. The weight of the upper structure 21 was set to 40 t, which is almost the same as that of a general wooden house.

Then, a seismic wave observed in the Hyogoken-Nanbu Earthquake was input to each of the foundations 23 in the horizontal direction, and the vibration damping effect of the upper structure 21 was examined. As a result, the maximum acceleration of the upper structure 21 in the horizontal direction was reduced to about 1/4, and it was confirmed that the seismic isolation effect was sufficiently exhibited.

Next, the seismic isolation effect when each of the seismic isolation devices A was applied to the seismic isolation floor was examined. That is, as shown in FIG. 7, each seismic isolation device A is provided at four corners between a floor member 26 as an upper structure and a foundation 23 installed on a plurality of rollers, and The same seismic wave as the test was input. As a result, it was found that each of the seismic isolation devices A had a sufficient seismic isolation effect even when used as a seismic isolation floor, and was applicable to seismic isolation floors such as precision machine rooms and computer rooms inside buildings. Was.

[0033]

As described above, according to the first aspect of the present invention, even if the upper structure is lightweight, the upper structure is supported by the spherical roller housed and held in the elastic bag, and the upper structure is Rolling can attenuate the horizontal vibration of the earthquake, and it is simple, compact and lightweight, and can effectively exhibit the seismic isolation function.

According to the second aspect of the present invention, the elastic bag is disposed in contact with and covers the outer periphery of the roller at substantially the center in the vertical direction between the first and second plate members, thereby displacing the elastic bag in the horizontal direction. At the same time, the frictional resistance between the elastic bag and the spherical roller can be increased, and the seismic isolation function can be more effectively exerted. Further, since the elastic bag is made of a rubber member, it is possible to easily procure an elastic bag which is low in cost and whose adjustment of the restoring force and the damping force is easy.

According to the third aspect of the present invention, the elastic bag is filled with an attenuator made of a liquid viscous material or a powdery or granular polymer material, so that the upper structure is prevented from inadvertently shaking. It is possible to improve the damping performance with respect to large ground vibration while suppressing the vibration, and it is possible to surely exert the seismic isolation effect.

According to the fourth aspect of the present invention, since a stopper for restricting the rolling of the roller is provided on the entire periphery of at least one of the first and second plate members, it is isolated from an earthquake having a large seismic intensity. The safety of the seismic device can be improved.

[Brief description of the drawings]

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

FIG. 2 is a perspective view of the seismic isolation device.

FIG. 3 is a view corresponding to FIG. 1, showing a state in which a first plate member has moved relatively to a second plate member.

FIG. 4 is a view corresponding to FIG. 1, showing another embodiment provided with a stopper for restricting the rolling of the roller.

FIG. 5 is a view corresponding to FIG. 1, showing another example of the shape of the elastic bag.

FIG. 6 is a schematic view showing a procedure of a test for applying a seismic isolation device to a private house and examining its seismic isolation effect.

FIG. 7 is a schematic view showing a procedure of a test for applying the seismic isolation device to a seismic isolation floor and examining the seismic isolation effect thereof.

FIG. 8 is a cross-sectional view showing a conventional seismic isolation bearing rubber type seismic isolation device.

[Explanation of symbols]

 A seismic isolation device 1 first plate member 2 second plate member 5 roller 8 elastic bag 12 stopper wall 21 upper structure 23 foundation 26 floor member (upper structure)

Claims (4)

[Claims] 1. A seismic isolation device that is provided between an upper structure and a foundation and suppresses the swing of the upper structure due to an earthquake. A first and a second plate member connected to a structure and the other connected to the foundation; a rolling member provided between the first and second plate members;
A spherical roller that supports the plate member on the upper structure side with respect to the plate member on the foundation side, and elastically connects the first and second plate members to each other while holding the roller inside. A seismic isolation device, comprising: a hollow elastic bag that extends when one of the two plate members moves horizontally relative to the other. 2. The seismic isolation device according to claim 1, wherein the elastic bag is made of a rubber member, and covers the roller in contact with the outer periphery of the roller at a substantially vertical center between the first and second plate members. A seismic isolation device characterized by the following. 3. The seismic isolation device according to claim 1, wherein the elastic bag body is filled with a damping agent made of a liquid viscous material or a powdery or granular polymer material. Seismic isolation device. 4. A seismic isolation device according to claim 1, 2 or 3, wherein a stopper for restricting the rolling of the roller is provided on the entire periphery of at least one of the first and second plate members. A seismic isolation device characterized in that: