JP2001336561A - Base isolation structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a damper capable of completely returning to its original state after the end of earthquake vibrations, and an isolator capable of sufficiently bearing with vertical load and having low horizontal stiffness, in a damper and an isolator composing a base isolation structure. SOLUTION: This base isolation structure is provided with the damper wherein a fuel tank 20 is deformably made by elastic element, a intake/discharge hole 12 is formed on a bottom plate 9 of a cylinder 1, a connecting member 6 extending from a piston rod 5 is journalled 7, 8, 17 to an upper structure 2, and a connecting member 13 extending from the bottom plate of the cylinder is journalled 14, 15, 19 to a lower structure 3; or an isolator made by laminating rubber plates and intermediate steel plates and structuring the rubber plates as plural divided bodies in each steel plate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an isolator and a damper interposed between an upper structure such as a building frame, a product case or an exhibition stand and a lower structure such as a base member. It is about the seismic structure.

[0002]

2. Description of the Related Art In a conventional seismic isolation structure, a separated type of an isolator mechanism and a damper mechanism is often used.
The current isolator mechanism is made by alternately stacking rubber and steel plates, and is strong against vertical pressure, and has the function of restoring the original state as a horizontal spring. Normally, horizontal movement of 20 to 30 cm is required for absorption, and the diameter of the isolator is 40 cm or more in order to withstand the eccentric load compressive force generated by the movement. The rigidity of the seismic isolation layer and the upper structure layer does not change much, and the seismic isolation effect is weakened.Therefore, it is not suitable for light-weight buildings. In many cases, it depends on a sliding steel plate (stainless steel) and is used only as a horizontal spring for restoring force.

Also, in a seismic isolation structure (see, for example, Japanese Utility Model Publication No. 5-20808) in which lead is inserted into the center of a laminated rubber isolator to provide a damper function, lead is deformed by plastic deformation. It is the isolator that absorbs the seismic energy and plays a role in returning the plastically deformed lead material to its original state. The magnitude of the horizontal spring force (restoring force) of this isolator Since is similar to the amount of deformation, the strain of plastically deformed lead often ends without being able to return to its original state due to the balance of the forces.

[0004] In addition, in the case of a steel plate, a steel rod, or the like, a damper that absorbs seismic energy by plastic deformation, a sliding friction damper (for example, see Japanese Patent Application Laid-Open No. H11-270183), a viscous damper, and the like, To insert lead and not return to the original state completely after the seismic vibration ends, like the damper, and to completely return to the original state after the earthquake ends,
The damper must be replaced or returned to its original state by other large power.

[0005]

Incidentally, in the case of the conventional example, since the damper absorbs seismic energy due to the material properties such as plastic deformation or sliding friction of the material used, the damper is required for the deformation. The force is always constant, and the spring force of the rubber of the isolator used for the restoring force is proportional to the magnitude of the deformation. It is difficult to completely return to the original state.

Further, the isolator provided with the laminated rubber supports the upper structure. As described above, when the diameter of the isolator increases, the rigidity of the seismic isolation layer increases, and the rigidity of the upper structure increases. Although it is suitable for the structure, there is a problem in applying such a rigid seismic isolation layer because the rigidity of a lightweight structure is low.

The present invention has been made in view of such a problem, and an object of the present invention is to provide a damper and an isolator that constitute a seismic isolation structure in a completely original state after the end of an earthquake vibration. An object of the present invention is to provide a damper capable of returning to a state, and to provide an isolator which can sufficiently withstand a vertical load and has low horizontal rigidity.

[0008]

In order to achieve the above object, a seismic isolation structure according to the present invention comprises an isolator and a damper interposed between an upper structure and a lower structure. A damper, a cylinder, a piston sliding on the inner surface of the cylinder, a piston rod extending from the piston, and a valve attached to the bottom surface of the cylinder;
A fluid tank disposed so as to surround the outer periphery of the cylinder, the fluid tank is formed of an elastic body so as to be deformable, a suction hole is formed in a bottom plate of the cylinder, and a discharge hole is formed in the valve. The connecting member extending from the piston rod is pivoted to the upper structure, and the connecting member extending from the bottom plate of the cylinder is pivoted to the lower structure.

Further, the damper is arranged at the center of the isolator.

The seismic isolation structure is composed of an isolator and a damper interposed between the upper structure and the lower structure, and the isolator is formed by laminating a rubber plate and an intermediate steel plate. Wherein the rubber plate is composed of a plurality of divided bodies in each of the intermediate steel plates, and the divided rubber plates are respectively opposed to a center of the intermediate steel plate around the intermediate steel plate. It is characterized by being arranged at a site.

In addition, a steel ball is arranged near each of the divided rubber plates, and a guide hole is formed on an intermediate steel plate located at a central portion of the steel ball so as to hold the steel ball. A position ball of the steel ball is formed on an upper or lower intermediate steel plate.

[0012]

Embodiments of the present invention will be described with reference to the accompanying drawings. In FIG. 1, reference numeral 1 denotes a cylinder interposed between an upper flange steel plate 2 and a lower flange steel plate 3, and a piston 4 sliding on the inner surface of the cylinder 1 is arranged in the cylinder 1. A piston rod 5 extends from the piston 4 toward the upper flange steel plate 2, and a connecting member 6 formed at the distal end of the piston rod 5 is rotated by a pin 8 provided on a rotary hinge 7. 7 is connected.

A valve 10 is mounted on the upper surface of the bottom plate 9 of the cylinder 1, and the valve 10 has a small diameter 1
One or a plurality of discharge holes 11 are formed. Also,
The bottom plate 9 of the cylinder 1 is formed with one or more suction holes 12 having a relatively large diameter. The bottom plate 9 of the cylinder 1 is also connected to the rotating hinge 14 via a connecting member 13 by a pin 15 provided on the rotating hinge 14.

The rotary hinge 7 is rotatably supported by a bearing 17 disposed between a shaft 16 of the rotary hinge 7 and the upper flange steel plate 2, and the rotary hinge 14 is 14 is rotatably supported by a bearing 19 disposed between the shaft 18 and the lower flange steel plate 3.

The cylinder 1 is surrounded by a deformable elastic rubber or poly-based or synthetic resin-based fluid tank 20 on its outer periphery (excluding the outer periphery of the upper surface). The inside is filled with a fluid such as oil or water. The cylinder 1, the piston 4, the piston rod 5, the valve 10, and the fluid tank 20 constitute a damper 21 for a seismic isolation structure.

Reference numeral 22 denotes a linear motion roller disposed at an upper portion in the cylinder 1, which serves as a guide when the piston rod 5 reciprocates. Reference numeral 23 denotes a linear motion roller.
A cushion stopper disposed near the line 22 restricts the rise of the piston 4, and an overflow hole 24 formed in the cylinder 1 is a fluid stopper in the cylinder 1. Is caused to overflow into the fluid tank 20 or the fluid in the fluid tank 20 is overflowed into the cylinder 1 so that the fluid due to abnormal pressure increase in the cylinder 1 and the fluid tank 20 It prevents leakage to the outside.

The damper 21 as described above can be used in combination with an ordinary isolator made of laminated rubber and an intermediate steel plate to constitute a seismic isolation structure. And the vertical load is applied to the seismic isolation structure by the building frame,
When a horizontal force is generated by the earthquake, the isolator tilts while receiving the eccentric pressure, and the damper 21
With the pin 8 as a fulcrum, it inclines in the direction in which the horizontal force is generated in accordance with the seismic energy. In the course of this inclination, the piston rod 5 extends from the cylinder 1 and raises the piston 4 sequentially in the cylinder 1. As the piston 4 rises, the valve 10 is opened, and for example, the oil in the fluid tank 20 is discharged from the suction hole 12 Is sucked into the lower part of the piston 4 in the cylinder 1 and the oil on the upper part of the piston 4
The fluid is returned into the fluid tank 20 through the through hole 24. The damper 21 absorbs the seismic energy considerably due to the suction operation of the oil from the suction hole 12.

In the process where the horizontal force acts in the opposite direction due to the seismic vibration, the damper 21 tends to return to the original upright state with the pin 8 as a fulcrum due to the restoring force of the isolator. During this return process, the piston rod 5 is sequentially placed in the cylinder 1 and the piston 4 is moved into the cylinder 1
, And the valve 10 is moved as the piston 4 descends.
Is closed, the oil sucked into the lower part of the piston 4 is gradually returned from the discharge hole 11 formed in the valve 10 to the fluid tank 20 through the suction / discharge hole 12, and the discharge hole 11 is
The seismic energy is further absorbed by the movement of the oil from the reservoir through the suction hole 12 into the fluid tank 20. And
Part of the oil in the fluid tank 20 is returned to the upper part of the piston 4 via the overflow hole 24.

From such a fluid tank 20 to the piston 4
The damper 21 continues to absorb seismic energy while repeating the process of moving the oil into the lower part of the piston and moving the oil from the lower part of the piston 4 into the fluid tank 20 a plurality of times.
When the earthquake ends, the damper 21 returns to its original upright state with the pin 8 as a fulcrum due to the restoring force of the isolator.

However, the restoring force of the isolator decreases as approaching the center of the seismic isolation structure, and the damper 21
Restore speed decreases. However, as time passes, the piston 4 is gradually lowered by the reduced restoring force of the isolator to bring the damper 21 closer to the vertical direction, and finally the damper 21 is completely returned to the original state. Let it return.

The fluid tank 20 and the cylinder
If the number and diameter of the discharge holes 11 and the suction and discharge holes 12 are determined in accordance with the optimal flow period of the seismic isolation structure, the damper 21 can reliably absorb seismic energy. Be adaptable.

Since the fluid tank 20 is made of a deformable elastic material such as poly or rubber, when the damper 21 is tilted due to the earthquake as described above, for example, the corner of the tank 20 is formed. Even when the tank 20 contacts the lower flange steel plate 3, the tank 20 is slightly deformed without being damaged,
It is possible to tilt the damper much further.
This allows the allowable tilt range of 1 to be expanded.
Moreover, since the fluid tank 20 is an elastic body, the pressure in the tank can be adjusted to the external pressure, so that the oil in the tank can flow smoothly.

The damper 21 is connected to the piston rod 5
The connecting member 6 extending from the upper flange steel plate 2 and the connecting member 13 extending from the bottom plate 9 of the cylinder 1 are pivoted to the lower flange steel plate 3, so that the connecting member 6 can be horizontally supported by the pin 8 in any direction. It can be freely tilted in the direction of force generation in response to seismic energy.

FIG. 2 shows a damper 21 according to the present invention arranged at the center of a circular isolator. FIG.
The damper 21 according to the present invention is disposed at the center of a rectangular isolator. In both figures, since the detailed configuration of the damper 21 has already been described in detail, the same reference numerals are given and the description thereof is omitted. 25 is a rubber plate,
Reference numeral 26 denotes an intermediate steel plate.
Are alternately arranged and stacked on the lower flange steel plate 3 to form an isolator. Then, the lower flange steel plate 3 is bolted to the foundation side base of the lower structure.
It is fixed to the plate 28. Reference numeral 29 denotes a hole for accommodating the damper 21 formed in the rubber plate 25 and the intermediate steel plate 26.

As described above, when the damper 21 according to the present invention is arranged at the center of the isolator, the entire seismic isolation structure is compacted, and in particular, the fluid tank 20 of the damper 21 is made of poly or poly. Since it is made of a deformable elastic body such as rubber, when the damper 21 is inclined,
A part of the fluid tank 20 includes the rubber plate 25 and the intermediate steel plate 26.
Even if the fluid tank 21 is deformed by contacting the storage hole 29 of the damper 21 formed in the above, there is no possibility that the fluid tank 21 is damaged.

FIGS. 4 and 5 show an embodiment of an isolator suitable for application to a relatively lightweight superstructure according to the present invention. , Rubber plates 25 and sandwiching steel plates 30 are alternately arranged and stacked. Each of the rubber plates 25 and the sandwiching steel plates 30 has a small area which is arranged as a divided body at each of the four corners around the intermediate steel plate 26 without having the same area as the intermediate steel plate 26 as in the conventional example. Is made of things. Each of the divided rubber plates 25 is disposed at a portion facing the center of the intermediate steel plate 26, respectively.

Such a laminated rubber plate 25 and an intermediate steel plate 26
Is interposed between the upper flange steel plate 2 and the lower flange steel plate 3, and the upper flange steel plate 2
Is fixed to a base plate 32 on the upper structure side by bolts 31, and the lower flange steel plate 3 is fixed to a base plate 28 on the base structure of the lower structure by bolts 27.

The isolator according to the present invention having the above configuration can be used together with a normal damper to constitute a seismic isolation structure. Since the seismic isolation structure is subjected to a vertical load by the building frame, when a horizontal force is generated by the earthquake, the isolator tilts while receiving the eccentric pressure as described above.

The inclination of the isolator is accompanied by the deformation of the rubber plate 25 in the direction of the generation of the horizontal force due to the earthquake. Each rubber plate 25 is arranged as a divided body around the intermediate steel plate 26. In the direction in which the horizontal force is generated, the divided bodies are opposed to each other, so that the rubber plate 25 on the intermediate steel plate 26 is prevented from being twisted, and the horizontal rigidity is reduced in the intermediate steel plate 26 while reducing the horizontal rigidity. Can sufficiently withstand vertical pressure. Therefore, even if the isolator is greatly inclined due to a large earthquake, each rubber plate 25 is restrained by the intermediate steel plate 26 and the vertical force is dispersed, and no excessive force is applied to each rubber plate 25. The vehicle is suitable for application to a relatively lightweight superstructure such as a product case or a display stand.

In the round isolator shown in FIG. 6, a large number of rubber plates 25 are respectively arranged at target positions around a circular intermediate steel plate 26 as divided bodies. In this isolator, the square isolator
Since they perform substantially the same operation as the data, the same members are denoted by the same reference numerals and description thereof will be omitted.

The isolator according to the present invention is used together with a damper as described above, and does not have any particular restrictions on the structure of the corresponding damper and the location where the damper is installed. In FIGS. 4, 5, and 6, the damper 21 is disposed at the center of the isolator.

A steel ball can be arranged near each of the divided rubber plates 25. That is, as shown in FIG.
The steel ball 33 is arranged near the divided rubber plate 25. And the intermediate steel plate 2 located at the center of the steel ball 33
6 is a guide ball 34 for holding and guiding the steel ball 33.
The steel ball 3 is provided on the intermediate steel plate 26 immediately above or directly below the intermediate steel plate 26 having the guide ball 34.
3 is formed with a position hole 35 for accommodating the top or bottom of the intermediate steel plate 2 (FIG. 7).
No. 6 was formed with a position hole 35).

In the isolator provided with the steel balls 33 in the vicinity of each of the divided rubber plates 25 as described above, the wind pressure and the seismic intensity at a normal wind speed of, for example, about 30 m / s are small (for example, seismic intensity 3 or less). In this case, the steel ball 33 is
The rubber plate 25 is stably accommodated in the rubber plate 25, and supports the upper structure and suppresses the horizontal movement of each rubber plate 25. And when the seismic intensity increases (for example, seismic intensity 3 or more), the steel ball 3
3 moves out of the position hole 35 and allows the isolator to tilt, while the steel ball 33 still supports the upper structure.

When the seismic vibration ends, the restoring force of each rubber plate 25 returns the isolator to the substantially original state, and the steel ball 33 returns to the position hole 35 to completely restore the isolator. State.

As described above, in the isolator provided with the steel balls 33 in the vicinity of each of the divided rubber plates 25, a large horizontal deformation generated at the time of an earthquake occurs while forming a small horizontal rigidity by the divided rubber plates 25. The rubber plates 25 and the steel balls 33 cooperate with each other to sufficiently withstand the eccentric pressure.

FIGS. 4, 5 and 6 show the case where the steel balls 33 are arranged in the vicinity of each of the divided rubber plates 25, and FIGS. 8 and 9 are also divided. An isolator having a steel ball 33 near each rubber plate 25 and having a damper 21 disposed at the center thereof is shown. FIG. 8 shows a state in which the steel ball 33 is accommodated in the position hole 35, and FIG. 9 shows a state in which the steel ball 33 is pulled out of the position hole 35. Also, as described above, the steel ball 33 is positioned
At the time of return to the control panel 35, the damper 21 completely returns to the original state as shown in FIG. 8, so that the upper structure completely returns to the original position.

[0037]

As described above, according to the present invention, in a seismic isolation structure including an isolator and a damper interposed between an upper structure and a lower structure, a cylinder and an inner surface of the cylinder are provided. A damper comprising a sliding piston, a piston rod extending from the piston, a valve attached to a bottom surface of the cylinder, and a fluid tank arranged to surround an outer periphery of the cylinder, The fluid tank is formed of an elastic body so as to be freely deformable, a suction hole is formed in a bottom plate of a cylinder, a discharge hole is formed in the valve, and a connecting member extending from the piston rod is pivoted to an upper structure and the cylinder is formed. The connecting member extending from the bottom plate is pivoted to the lower structure, so it is a damper that can completely return to the original state after the end of the earthquake vibration, and easily responds to the direction of the earthquake To form, a seismic isolation structure that can absorb the seismic energy.

When the damper is arranged at the center of the isolator, a compact integrated seismic isolation structure is obtained.

In a seismic isolation structure including an isolator and a damper interposed between an upper structure and a lower structure, the isolator is formed by laminating a rubber plate and an intermediate steel plate, Since the rubber plate is composed of a plurality of divided bodies in each of the intermediate steel plates, a seismic isolation structure which can sufficiently withstand a vertical load and has an isolator having low horizontal rigidity is provided.

Then, a steel ball is arranged near each of the divided rubber plates, and a guide hole is formed on an intermediate steel plate located at the center of the steel ball to hold the steel ball and to form a steel ball. When the position ball of the steel ball is formed on the upper or lower intermediate steel plate, the vertical deformation of each rubber plate is suppressed small while forming small horizontal rigidity by the divided rubber plate,
Each rubber plate and steel ball cooperate with each other even in the event of a large horizontal deformation caused by an earthquake, resulting in a seismic isolation structure with an isolator that can sufficiently withstand eccentric pressure.

[Brief description of the drawings]

FIG. 1 is a sectional view of a damper according to the present invention.

FIG. 2 is a perspective view of a damper according to the present invention;
It is sectional explanatory drawing arrange | positioned in the center part of a table.

FIG. 3 shows a damper according to the present invention in a rectangular isolator.
It is sectional explanatory drawing arrange | positioned in the center part of a table.

FIG. 4 is a side view of the integrated seismic isolation structure according to the present invention.

FIG. 5 is a sectional view taken along the line AA of FIG. 4;

FIG. 6 is a sectional view of another embodiment of the integrated seismic isolation structure according to the present invention.

FIG. 7 is a sectional view of an isolator provided with a steel ball according to the present invention.

FIG. 8 is a longitudinal sectional view of one embodiment of the seismic isolation structure according to the present invention.

FIG. 9 is a longitudinal sectional view for explaining the operation.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder 2 Upper flange steel plate 3 Lower flange steel plate 4 Piston 5 Piston rod 6.13 Connecting member 7, 14 Rotating hinge 9 Bottom plate of cylinder 10 Valve 11 Discharge hole 12 Suction and discharge hole 20 Fluid tank 25 Split rubber plate 26 Intermediate steel plate 33 Steel ball 34 Guide ball 35 Position ball

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // E04H 9/02 331 F16F 9/32 H

Claims (4)

[Claims] 1. A seismic isolation structure comprising an isolator and a damper interposed between an upper structure and a lower structure,
A cylinder, a piston sliding on the inner surface of the cylinder, a piston rod extending from the piston, a valve attached to the bottom surface of the cylinder, and a fluid tank arranged to surround the outer periphery of the cylinder A connection member extending from the piston rod, wherein the fluid tank is formed of an elastic body so as to be freely deformable, a suction hole is formed in a bottom plate of the cylinder, a discharge hole is formed in the valve, and And a connecting member extending from the bottom plate of the cylinder is pivoted to the lower structure. 2. The seismic isolation structure according to claim 1, wherein a damper is disposed at a center of said isolator. 3. A seismic isolation structure comprising an isolator and a damper interposed between an upper structure and a lower structure,
An isolator formed by laminating a rubber plate and an intermediate steel plate, wherein the rubber plate is formed into a plurality of divided bodies in each of the intermediate steel plates, and the divided rubber plate is intermediately disposed around the intermediate steel plate. A seismic isolation structure characterized by being placed at locations facing the center of a steel plate. 4. A steel ball is arranged in the vicinity of each of the divided rubber plates, and a guide hole is formed on an intermediate steel plate located at a central portion of the steel ball so as to hold the steel ball. 4. The seismic isolation structure according to claim 3, wherein a position ball of said steel ball is formed on an upper or lower intermediate steel plate.