JPH09256673A - Base isolation device for structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To damp vibration energy not only in the horizontal direction but also in the vertical direction of a structure while having simple constitution and reset the structure to an original position by using inertial force in the vertical direction with the load of the structure. SOLUTION: A pneumatic cylinder 4, which has one end and the other end connected to a foundation beam 2 for a structure and to a ground-side foundation 1 via spherical articulated joints with balls 6 and pivot bearings 8 respectively jointed together, respectively, and a piston 5 are provided. With the displacement of the structure relative to the ground, the piston 5 is set in and out of the cylinder 4 to cause damping effect so that the clinder 4 and the piston 5 can be oscillated to the direction of the displacement via the respective articulated joints.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a seismic isolation device for a structure.

[0002]

2. Description of the Related Art A laminated rubber isolator is known as a seismic isolation device for structures. The laminated rubber isolator is composed of a pair of plates, in which a rubber plate and a steel plate are alternately laminated in a sandwich form.The laminated rubber isolator is interposed between the ground-side foundation and the structure to be isolated, While vertically supporting, it acts as a soft spring in the horizontal direction and absorbs seismic input energy as elastic strain energy.

[0003]

However, the conventional seismic isolation device of this type is intended only for horizontal vibration (so-called horizontal vibration) of the structure, and copes with vertical vibration (so-called vertical vibration). It wasn't something to do. That is, in a place where the epicenter is relatively shallow, the pitch component is large and acts on the ground surface, and the seismic energy is extremely large. For example, it was concluded that the Great Hanshin Earthquake that caused great damage in Japan recently had a huge seismic intensity of 7 or more, and collapses of structures have been observed everywhere.
It has been reported that such a collapse is caused not only by rolling but also by pitching.

On the other hand, in addition to the conventional horizontal seismic isolation device, it is possible to add a seismic isolation device having a vertical spring characteristic, but the structure becomes complicated and the construction period increases. However, there is a problem that the cost increases significantly.

Further, in the conventional laminated rubber isolator, the structure is returned to the current position by the restoring force of the plurality of laminated rubber plates. The rubber plate supports the load of the structure. Since it is necessary to have a function and a spring function in the horizontal direction, and it is necessary to design not only the load supporting function and the spring function but also the restoring function, it is difficult to design.

The present invention solves the above problems, and has a simple structure and is capable of attenuating not only horizontal vibration energy with respect to a structure but also vertical vibration energy. The purpose is to provide a seismic isolation device.

It is another object of the present invention to provide a seismic isolation device for a structure which can utilize the vertical inertial force due to the load of the structure to restore the existing position of the structure. .

[0008]

In order to achieve the above object, the invention according to claim 1 of the present invention has one end on the ground side and the other end on the foundation side of the structure via a universal joint. An air damper including a connected cylinder and piston is provided, and the relative displacement between the ground and a structure causes the piston to project and retract with respect to the cylinder to generate a damper effect, and the cylinder and the piston are connected via the universal joints. It is characterized by swinging in the displacement direction.

Here, the "universal joint" includes a universal joint and a ball joint joint formed by connecting a pivot shaft and a pivot bearing, and in a state where the two are connected, a 360 degree relative relative to the connection center as a base point. It is a mechanical element that enables oscillating motion, and by connecting this to both the ground side and the structure, it is possible to freely move to cope with vibration from any input direction.

When an earthquake occurs, vibration energy is propagated to the air damper via the universal joint on the ground side, the vibration energy is attenuated by the damper effect of the air damper, and the attenuated vibration energy is transmitted to the universal joint on the structure side. Is propagated to the structure via. Since the air damper is connected to the ground and the structure by the universal joint, it damps not only all horizontal vibrations but also vertical vibrations as well as combined horizontal and vertical vibrations. Exert function. Further, due to the friction in the universal joint, a part of the vibration energy is converted into heat energy, and as a result, a slight damping effect of the vibration energy is generated in the universal joint.

The invention according to claim 2 is characterized in that the axial direction of the air damper is set obliquely when viewed from the side. According to this configuration, both the horizontal and vertical vibrations can be efficiently damped by a single air damper.

The invention according to claim 3 is characterized in that the pressure chamber is hermetically held in a state where a predetermined pressure chamber is formed between the cylinder and the piston of the air damper. If the pressure chamber inside the air damper is kept airtight, the pressure chamber between the cylinder and piston will be pressurized or depressurized when the piston moves in and out of the cylinder due to the occurrence of an earthquake. It is generated, and the force can return the structure to the current position.

According to a fourth aspect of the present invention, the pressure chamber of the air damper communicates with the outside air through pressure adjusting means such as an orifice and a check valve. According to this configuration, a more excellent damper effect can be produced due to the phase difference between the air flow in / out speed and the vibration displacement speed that accompany the piston moving in and out.

The invention as set forth in claim 5 is characterized in that the pressure chamber of the air damper is connected to a pressurizing device. With this configuration, the air pressure that causes the damper effect can be properly adjusted.

According to a sixth aspect of the present invention, a mechanical spring means is arranged in the pressure chamber. According to this configuration, in addition to the air pressure, the mechanical biasing force of the spring means can be used as a damper effect.

According to a seventh aspect of the present invention, there is provided a support plate provided on at least one of the ground side and the structure side, and a rolling bearing that extends from the other side toward the support plate and is movable on the support plate. And a support leg having a slide bearing, and the support plate is a concave curved surface having a pole on an extension axis of the support leg. According to this configuration,
In normal times, the structure is supported on the ground via the support board and the support legs. Here, when an earthquake occurs,
The rolling or sliding bearing of the support leg rolls or slides on the concave curved surface of the support board, but the horizontal component of the earthquake is damped by the delay of the mechanical response and the sliding friction. When the earthquake ends, the supporting plate has a concave curved surface with a pole on the extension axis of the supporting leg, so the force of the supporting leg axis toward the polar point of the concave curved surface due to the vertical inertial force due to the load of the structure. Eventually, the axis of the supporting leg stops at the pole of the concave curved surface, and the structure returns to the current position.

The invention according to claim 8 is characterized in that a depression is formed at the extreme point of the concave curved surface for positioning and holding the rolling bearing or the sliding bearing. According to this configuration, the horizontal component of the earthquake is attenuated when the rolling bearing or the sliding bearing gets over the dent in the event of an earthquake, and the bearing is ensured when the current position return operation of the structure at the end of the earthquake is completed. Positioned and held.

According to a ninth aspect of the present invention, the air damper according to any one of the first to sixth aspects is provided between either the ground side or the structure side and the support plate according to the seventh or eighth aspect. It is characterized by that. According to this structure, a synergistic effect is produced according to each combination.

According to a tenth aspect of the present invention, there is provided a supporting plate provided on at least one of the ground side and the structure side, and a rolling bearing which extends from the other side toward the supporting plate and is movable on the supporting plate. 7. A support leg having a slide bearing, the support plate being a flat plate orthogonal to the axis of the support leg, and between the ground plate and the structure side and the support plate. An air damper according to any one of the above is provided. According to this configuration, it is not possible to return the structure to the present position by utilizing the inertial force of the structure as in claim 7, but there are other effects.

The invention according to claim 11 is characterized in that the support leg is formed separately from the ground side and the structure side. With this configuration, replacement work when the support leg is damaged is easy.

[0021]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

1 and 2 show a first embodiment of the present invention. In the figure, 1 is a foundation on the ground side, and 2 is a foundation beam at the bottom of the building. Two air dampers 3 constituting the seismic isolation device according to the present invention are interposed between the two. One air damper 3 is a vertical type in which the foundation 1 and the beam 2 are vertically connected, and the other air damper 3 is an inclined type in which the foundation 1 and the beam 2 are obliquely connected, Since the basic structure is the same in both cases, they will be described collectively by the same reference numerals.

Each of the air dampers 3 is composed of a pneumatic cylinder 4 having a lower end coupled to the base 1 side, and a ram type piston 5 which is inserted into the upper side of the cylinder 4 so as to be retractable and whose upper end is connected to the lower portion of the beam 2. It is an air damper. Balls 6 are integrally formed on the lower end of the cylinder 4 and the upper end of the piston 5, respectively. The balls 6 are connected to the base 1 and the lower part of the beam 2 via bolts and nuts 7, respectively. Bearings are swingable to form a kind of ball joint joint (universal joint).

Further, the pressure chamber 4a surrounded by the lower portion of the piston 5 and the cylinder 4 communicates with the outside air via the orifice 9. In the figure, one orifice 9 of the vertical air damper 3 is connected to the accumulator 10 through a conduit, and the other orifice 9 is open to the atmosphere side. In addition, the orifice 9 of the inclined air damper 3
Are both closed. However, all of them may be open to the atmosphere, or may be connected to the pressurizing mechanism through a conduit.

The vertical air damper 3 contributes to support the load of the structure because the pressure chamber 4a is pressurized. Of course, a separate support mechanism may be provided between the ground-side foundation 1 and the structural foundation beam. Further, since the inclined air damper 3 is also sealed with a predetermined amount of air in the pressure chamber 4a, this also contributes to supporting the vertical component force of the structural load to some extent.

When the seismic wave propagates to the foundation 1, it is transmitted to the foundation beam 2 of the structure through the pivot bearing 8-ball 6-cylinder 4-pressure chamber 4a-piston 5-ball 6-pivot bearing 8 in order. Since the ball 6 and the pivot bearing 8 can be displaced relative to each other in any direction, they can freely move in any input direction of seismic waves. At this time, the vibration input energy of the earthquake can be attenuated due to the delay of each mechanical response, the spherical friction between the pivot bearing 8 and the ball 6, and the damper effect of the air existing in the pressure chamber. The seismic energy damping effect extends to seismic waves in all three-dimensional directions.

Further, due to the relative movement of the ground-side foundation 1 and the foundation beam 2, the atmosphere is introduced into the pressure chamber 4a of the vertical air damper 3 through the orifice 9. The orifice effect causes the piston 4 to move in and out. The speed can be slowed down, which can also attenuate the input energy. On the other hand, since the pressure chamber 4a of the tilted air damper 3 in this embodiment is sealed, the relative movement of the foundation 1 and the foundation beam 2 pressurizes or depressurizes the air in the pressure chamber 4a, but the earthquake ends. Then, a force to return to the original pressure is exerted, and as a result, the structure is returned to the present position.

FIG. 2 shows a modification of the air damper 3. First, in the air damper 3 shown in (a), instead of the ram type piston 5, a plunger 12 is integrally projectingly provided on an upper portion of a piston 11, and the upper and lower pressure chambers 4a and 4b partitioned by the piston 11 are The pressure chambers 4a and 4b are formed with a pair of orifices 14 so as to communicate with each other by an orifice groove 11a formed on the outer circumference of the piston 11, and communicate the inside and outside of the cylinder 4 with the outside. Further, the orifice 14 on one side is connected to the check valve 16 via the pipe line 15 so that the flow is stopped at the time of intake or exhaust, and due to this difference in flow resistance, the damper is I try to bring effect.

In addition to the above-mentioned structure, the air damper 3 shown in (b) has a compression coil spring 18 inserted in the lower pressure chamber 4a.
Is always biased toward the raised position.

The air damper 3 shown in (c) is a ram type piston 5 similar to that of the first embodiment, but has a lower pressure chamber 4a.
A compression coil spring 18 is inserted therein, and in addition to air pressure, this spring pressure constantly urges the piston 5 to a raised position. Further, an orifice 14 communicating with the pressure chamber 4a at the highest position of the piston 5 is connected to a check valve 16 via a pipe line 15.

FIG. 3 shows another modification of the air damper 3. What is shown in this figure is a spherical plain bearing 19 (for example, as a universal joint that replaces the ball joint joint of the above-mentioned embodiment).
"Pillow ball (trade name)" manufactured by Thomson Japan Co., Ltd.)
Is adopted. The spherical plain bearing 19 includes a rod-shaped main body 19a, a bush 19b formed at one end of the main body 19a and having a spherical sliding surface inside, and a spherical inner ring rotatable and swingable with respect to the sliding surface of the bush 19b. 1
It consists of 9c. A cylinder 19d or a piston 19e forming an air damper is integrally provided at the other end of the main body 19a.

In this embodiment, the cylinder 1
An orifice 19f is formed on the side of 9d,
As in the above-described embodiment, the structure of pressurizing the pressure chamber may be adopted, or the orifice 19f may be closed to seal the pressure chamber in order to realize the current position returning action.

On the other hand, a pillar 19A is fixed to the ground side foundation, and a pillar 19B is fixed to the structure side. Metal fittings 19C are capped at the ends of both pillars 19A and 19B, and end portions 19A and 19B of the pillars and fittings 19C.
A through hole is formed in the through hole.

In the spherical inner ring 19c of the spherical plain bearing 19,
A bolt 19D is fixed through, and the bolt 19D is passed through the through holes of the pillars 19A, 19B and the metal fitting 19C via the spring washer 19E, and the nut 19 is attached to the end thereof.
F is screwed.

Also in this embodiment, similarly to the above-mentioned embodiments, there is an effect that the seismic input from all three-dimensional directions can be attenuated. As a method of connecting the spherical plain bearing 19 to the cylinder 19d or the piston 19e, the bearing side may be a male screw or a female screw. Further, FIG. 4 shows a second embodiment of the present invention. The same parts as those of the first embodiment will be designated by the same reference numerals, and different parts or newly added members will be described by using different reference numerals.

In the figure, a pedestal 20 is integrally embedded in the base 1, and a flat plate-shaped support board 21 is provided at the projecting end of the pedestal 20 on the base 1. A support leg 22 is vertically provided at a lower portion of the beam 1 so as to face the upper surface of the support board 21.
A plurality of balls 23 forming a rolling bearing provided at the lower end of the support 23 are rotatably brought into contact with the seating surface 21a of the support board 21 to deposit the weight of the structure on the support board 21.

Further, on both sides of the support board 21, a pair of vertical air dampers 3, one end of which is connected to the support board 21 and the other end of which is connected to the beam 2 side, are arranged, and the inclined air damper 3 is further provided on one side. It is arranged. Unlike the first embodiment, each air damper 3 is arranged in an inverted state, but its function is exactly the same.

Further, in this embodiment, the structure load is not directly supported by the air damper 3, but the support leg 2 is exclusively used.
It is received by the support board 21 through 2. That is, when an earthquake is input in the stationary state shown in the figure, the supporting leg 2 is moved due to the relative displacement.
2 moves on the support board 22 while rolling the ball 23.

Along with this movement, each air damper 3 has a ball 6
Oscillates through, the piston 5 comes out of the cylinder 4,
By the negative pressure of the pressure chamber 4a at the time of protrusion and the pressurization at the time of sinking, the swing of the structure side is suppressed, and at the same time, it acts as a force for forcibly returning the support leg 22 to the original position on the support board 21 shown in the figure. . Therefore, after the vibration is completed, the original position is quickly restored. Of course, due to the damper effect due to the air pressure during the expansion and contraction, the input of the vibration to the structure side is reduced.

FIG. 5 shows a third embodiment which is a further development of the second embodiment. In the figure, the support board 21
The seating surface 21b is inclined in the shape of a concave curved surface having a pole at the center, and a depression 21c is formed at the pole.

On the other hand, the bottom surface of the support leg 22 is a curved convex portion conforming to the curved surface, and a large-diameter ball 24 which constitutes a rolling bearing is arranged in the center thereof, and the lower portion of the ball 24 Is engaged with the recess 21c, and a plurality of small-diameter balls 25 are arranged around the ball 24.

Therefore, in this structure, a large-diameter ball 2 is generated by inputting a vibration of a predetermined magnitude or more.
4 rides on the recess 21c and moves along the seating surface 21b, but due to the weight (inertial force) of the structure, the bottom of the curved surface,
That is, the force for returning to the original position is always applied, and after the vibration is completed, it is quickly returned to the original position shown in the figure. When returning to the current position, the large-diameter ball 24 falls into the recess 21c and the support leg 22 is positioned.

The vertical air dampers 3 are arranged on both sides of the support board 21 and perform the same returning action and damper action as those of the second embodiment. Since the required acting force is small,
It is sufficient to use a small one.

FIG. 6 shows a fourth embodiment which is a further development of the third embodiment. In the figure, a support block 30 is provided so as to project from the upper center of the support board 21, and a central convex portion 31a of a support plate 31 fixed to the lower portion of the beam 2 is provided so as to face the center of the top of the support block 30. And a plurality of balls 32 forming a rolling bearing are arranged around the periphery of the convex portion 31a.

Further, at the peripheral edge of the support block 30, a concave seating surface 21d is formed on the upper surface of the support board 21, and a recess 21e is provided at the lowest position thereof. A plurality of support legs 3 are provided around the support plate 31 so as to face it.
3 is projected, and the ball 34 provided at the tip thereof is brought into contact with the recess 21e.

The supporting legs 33 are connected to each other by a connecting rod 35 penetrating the supporting block 30 in the lateral direction so that their movements are restricted. A link 36 is interposed between each connecting rod 35 and the support leg 33, so that a relative inclination can be allowed.

Therefore, in this embodiment, the support board 21 and the support block 3 on the upper side of the support board 21 due to the input of seismic vibration.
Relative movement is made at two points on the top surface of 0, and after the swaying is stopped by the gravity, it quickly converges to the original position shown in the figure. In the figure, the connecting rod 3
Although the support legs 33 are connected to each other by means of 5, the air damper 3 described above is incorporated in this portion, whereby a damper effect due to this can be obtained.

7 to 10 show the fifth to eighth embodiments of the present invention, and can achieve the same effects as the above-mentioned embodiments. In the fifth embodiment, the air damper 3 according to the second embodiment (shown in FIG. 5) is deleted and the rolling bearing (ball 2
A plurality of support legs 22 having 4) are provided.

In the sixth embodiment, the support block 30 according to the third embodiment (shown in FIG. 6) is used as the support leg of the convex portion 21A which is integrated with the support board 21, and the support plate 31 on the structure side.
A support leg 31A projecting downward from is provided, the support plate 31 on the structure side is constituted by a single concave curved surface-shaped seating surface 31b, and a recess 31c is provided in the center thereof. In addition, a cushioning material 37 such as rubber is provided on the outer periphery of the protrusion 31A and the rising portion 21B formed at the end of the support board 21. As a result, in the event of a large earthquake, the support leg 31A is provisionally provided. Even if the bump collides with the convex portion 21A or the rising portion 21B of the support board 21, the impact can be mitigated. The cross-sectional shape of the cushion material 37 may be rectangular, semicircular, or triangular.

In the seventh embodiment, the central portion of the support board 21 in the fifth embodiment (shown in FIG. 7) is raised to support the support legs 2.
1A, the ball 24 is rotatably supported at the tip thereof, and the lower surface of the support plate 31 is formed as a concave curved seating surface 31b on which the ball 24 rolls.
A cushion material 37 is provided on the outer peripheral portion of the.

In the eighth embodiment, the support plates 21 having the same shape are arranged on the ground side and the structure side, and the support legs 38 having an H-shaped cross section are arranged separately from the support plates 21 and the support plates are provided. Ball 2 as a rolling bearing on the upper and lower ends of the customer 38
4 is rotatably supported.

In the second to eighth embodiments, the contact between the support leg and the support plate is constituted by the rolling bearing, but a sliding bearing in which low friction materials such as Teflon (registered trademark) are brought into contact with each other. But of course it is okay. Further, in each of the above figures, the concave curved surface is represented two-dimensionally, but when viewed two-dimensionally, it has a ring shape.

FIG. 11 shows an example of the layout of the seismic isolation device described above with respect to the actual structure. In the figure, the beam 2 has a rectangular shape, and L is attached to the lower part of the corner.
A total of four air dampers 3 having a character shape and one air damper 3 arranged inside the beam 2 at a position where the L shape is half-divided are arranged as a set. In addition, a total of four air dampers 3 and one air damper 3 arranged inside the beam 2 in a T-shape and arranged in a total of four are arranged at the lower part in the center in the lateral direction and the longitudinal direction. . The orifices of the respective air dampers 3 may be communicated with each other via a pipe or the like, or may be used independently.

It should be noted that the above arrangement intervals and the number of arrangements are set according to the pressure resistance of each air damper 3 and the scale of the structure, and are not limited to those shown in the drawings. In addition to the combination of the individual air dampers 3 shown in FIGS.
Needless to say, it may be incorporated in a seismic isolation device having a structure of 0 and used.

FIG. 12 shows a case where the seismic isolation device shown in FIG. 11 is connected to a pressurizing device. In the figure, a high-pressure pipe 40 is arranged inside the beam 2, one end of which is connected to a high-pressure compressor 42 through an accumulator 41, and the other end is a corner portion through a branch pipe 43.
By connecting to each of the air dampers 3 at the center in the lateral direction and the longitudinal direction, the high pressure air stored in the accumulator 41 is supplied to each of the air dampers 3, and the structure is supported while being constantly maintained at a constant pressure. .

FIG. 13 shows still another embodiment of the arrangement shown in FIG. In the figure, as an alternative to the air damper arranged inside the beam 2, two anchors 50 projecting on the foundation 1 are arranged at two central places in a rectangular space surrounded by the beam 2. The anchor 50 and each air damper 3 are connected in an X shape by a connecting means.

As the connecting means, a wire 51 may be used as shown by the alternate long and short dash line in the figure, or a spring member 52 may be used for connection, and a cylinder-piston 53 for allowing expansion and contraction at an intermediate position. May be interposed, or a combination of a turnbuckle 54 for length adjustment and a small cylinder-piston 55 may be used. In each case,
When the vibration is input, these connecting means expand and contract in the input direction, and the elasticity thereof causes the beam 2 to be forcibly returned to the original position.

In the above-mentioned cabinet embodiment, the air damper is adopted as a damper for attenuating the seismic input. However, it goes without saying that a damper containing oil or the like may be adopted.

Of course, the same effect can be obtained by reversing the top and bottom of the second to eighth embodiments.

[0060]

As is clear from the above description of the embodiments, in the seismic isolation device for a structure according to claims 1 to 6, a three-dimensional arbitrary input direction is obtained via a universal joint. Also, due to the damper effect of the air damper, the vibration energy for the building can be attenuated. The above operation is performed regardless of the mode of vibration, such as horizontal and vertical directions, or combined vibrations of these, so it is highly adaptable to the direction of vibration, and even for unclear pitching. It is possible to take sufficient measures to enhance the safety of the structure.

Further, in the seismic isolation device for a structure according to claim 7 or 8, the structure can be quickly returned to the present position by utilizing the vertical inertial force due to the load of the structure. .

Further, in the seismic isolation device for a structure according to claims 9 to 11, these effects are selectively exhibited.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an air damper that constitutes a seismic isolation device according to a first embodiment of the present invention.

2A to 2C are cross-sectional views showing a modified example of the air damper.

FIG. 3 is a side sectional view showing another modified example of the air damper.

FIG. 4 is a sectional view showing a second embodiment of the present invention.

FIG. 5 is a sectional view showing a third embodiment of the present invention.

FIG. 6 is a sectional view showing a fourth embodiment of the present invention.

FIG. 7 is a sectional view showing a fifth embodiment of the present invention.

FIG. 8 is a sectional view showing a sixth embodiment of the present invention.

FIG. 9 is a sectional view showing a seventh embodiment of the present invention.

FIG. 10 is a sectional view showing an eighth embodiment of the present invention.

FIG. 11 is a plan view showing an arrangement of the seismic isolation device of the present invention with respect to a structure.

FIG. 12 is a plan view showing another example of the same arrangement.

FIG. 13 is a plan view showing still another example of the same arrangement.

[Explanation of symbols]

1 Ground Foundation 2 Structural Foundation Beam 3 Air Damper 4 Pneumatic Cylinder 5 Piston 6,8 Ball Joint Joint (6 Ball, 8 Pivot Bearing) 9,14 Orifice 10,41 Accumulator 16 Check Valve 18 Compression Coil Spring (Mechanical Spring Means) ) 21 support board 22 support legs 23, 24, 25, 32, 34 ball (rolling bearing) 42 compressor (pressurizing device)

Claims (11)

[Claims] 1. An air damper comprising a cylinder and a piston, one end of which is connected to the ground side and the other end of which is connected to a foundation side of a structure via a universal joint, and the cylinder is provided by relative displacement between the ground and the structure. A seismic isolation device for a structure, characterized in that the cylinder and the piston are swung in the displacement direction via the universal joints while the piston is projected and retracted to generate a damper effect. 2. The seismic isolation device for a structure according to claim 1, wherein the axial direction of the air damper is set obliquely when viewed from the side. 3. The seismic isolation device for a structure according to claim 1, wherein the pressure chamber is hermetically held in a state in which a predetermined pressure chamber is formed between the cylinder and the piston of the air damper. 4. The structure according to claim 1, wherein the pressure chamber of the air damper communicates with the outside air through pressure adjusting means such as an orifice and a check valve. Seismic isolation device. 5. The seismic isolation device for a structure according to claim 3, wherein the pressure chamber of the air damper is connected to a pressurizing device. 6. The seismic isolation device for a structure according to claim 1, wherein a mechanical spring means is arranged in the pressure chamber. 7. A supporting plate provided on at least one of the ground side and the structure side, and a supporting leg having a rolling bearing or a sliding bearing extending from the other side toward the supporting plate and movable on the supporting plate. The seismic isolation device for a structure, wherein the support board is a concave curved surface having a pole on an extension axis of the support leg. 8. The seismic isolation device for a structure according to claim 7, wherein the pole portion of the concave curved surface is formed with a depression in which the rolling bearing or the sliding bearing is depressed and positioned and held. 9. A structure comprising the air damper according to claim 1 provided between any one of the ground side and the structure side and the support board according to claim 7 or 8. A seismic isolation device. 10. A supporting plate provided on at least one of the ground side and the structure side, and a supporting leg having a rolling bearing or a sliding bearing extending from the other side toward the supporting plate and movable on the supporting plate. The support plate is a flat plate orthogonal to the axis of the support leg, and the air damper according to any one of claims 1 to 6 is provided between the support plate and either the ground side or the structure side. A seismic isolation device for structures characterized by being provided. 11. The support leg is formed separately from the ground side and the structure side.
The seismic isolation device for the structure according to any one of 1.