JPH09317029A - Base isolation structure for building or the like - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent earthquake damages by laying a base isolation structure between a lower panel secured to a foundation and an upper panel secured to a building, coupling spherical projections formed on many plates and another plate to the spherical recesses on the latter plate, and superposing all the plates via gaps with one another. SOLUTION: A steel plate 10 secured to a foundation 1 moves, due to an earthquake lateral shake, and laterally slides into the projection 7 of an upper steel plate 8, thereby pushing up the projection, 7. Also, the weight of a building acts on the upper steel plate 10 and applies a braking force thereto. The motion of the steel plate 10 is thereby stopped. The upper steel plate 8, then, moves and the projection 7 thereof laterally slides into the recess 9 of the steel plate 10. The motion of the steel plate 8 is stopped, due to a braking force resulting from the weight of the building. Similarly, the projection 7 and the recess 9 of steel plates 8 and 10 at an upper level sequentially slides in a lateral direction. Thus, a total lateral slide distance is set at a value larger than the predicted maximum amplitude of a lateral shake, and the lateral slide is kept at such a level as stopped within the spherical projections 7 and 9 at an amplitude equal to or smaller than the value. According to this construction, the upper panel can be kept free from the effect of a steel material fixed to the building, upon occurrence of an earthquake, and the occurrence of earthquake damages can be prevented.

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seismic isolation structure for a building or the like, and more specifically, seismic isolation for reducing the vibration of the foundation caused by an earthquake from being transmitted to the building to reduce the earthquake damage of the building. Regarding the structure.

[0002]

2. Description of the Related Art Various seismic isolation structures have been proposed and put to practical use as seismic isolation structures for preventing the vibration of the foundation due to an earthquake from being transmitted to buildings. For example, a structure having a seismic isolation mechanism such as cushion rubber, rolling balls, and a bundle of rods installed between a foundation and a building is well known.

However, each of the seismic isolation mechanisms tries to provide seismic isolation by utilizing the elasticity of rubber, the movement of balls, the bending of rods, etc., and the seismic isolation effect cannot be said to be perfect. There is a point.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems. When the foundation of a building vibrates, a large number of plates constituting the seismic isolation mechanism move to absorb energy. However, it is configured to receive the resistance that acts as a braking force, and effectively absorbs the vibration of the earthquake. The task is to provide a seismic structure.

[0005]

As a means for solving the above problems, a seismic isolation structure for a building or the like according to claim 1 of the present invention is a base plate fixed to a foundation and a base plate fixed to a building. In a seismic isolation structure such as a building in which a seismic isolation mechanism is installed between a board and the seismic isolation mechanism, the seismic isolation mechanism provides a large number of plates on one plate with a spherical convex surface that is larger than the spherical convex surface on the other plate. It is characterized by adopting a structure in which the spherical concave surfaces are provided so as to engage with each other so that there is a slight gap between the plates.
Further, a spherical convex surface provided on one plate with a large number of plates is engaged with a spherical concave surface provided on the other plate with a radius larger than the spherical convex surface, and superposed so that a slight gap exists between the plates. A flexible connecting member for connecting the upper board fixed to the building and the lower board fixed to the foundation may be arranged outside the seismic isolation mechanism having the above structure.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a seismic isolation structure in a building according to the present invention will be described below with reference to the drawings.

In the drawing, reference numeral A indicates a seismic isolation mechanism in a building according to the present invention. The seismic isolation mechanism A in the building is fixed to a foundation 1 by a required number of anchor bolts 2 as shown in FIG. It is installed between the lower plate 3 of the steel material and the upper plate 6 of the steel material fixed to the building 4 by the required number of fastening bolts 5. As for the detailed structure of the seismic isolation mechanism A, as shown in FIG. 4, steel plates 8 provided with a large number of spherical convex surfaces 7 having a diameter r at regular intervals as shown in FIGS.
As shown in FIG. 3, a steel plate 10 having spherical concave surfaces 9 having a diameter R larger than the spherical convex surfaces 7 is provided on both sides thereof as shown in FIG. 3, and the convex surface 7 is provided on the concave surface 9. A large number of stages are stacked so that a slight gap h is formed between the steel plate 8 and the steel plate 10 by engaging with each other, and the steel plates 10 are positioned at the lowermost stage and the uppermost stage. The lower steel plate 10 is connected to the lower plate 3, and the uppermost steel plate 10 is connected to the upper plate 6 of the steel.

The convex surface 7 of the above-mentioned steel plate 8 and the steel plate 1
In order to cause stagnation between the concave surface of 0,
As described above, the gap h is formed between the steel plate 8 and the steel plate 10.
Not only to prevent them from coming into contact with each other, but also to lubricate the contact surface between the convex surface 7 and the concave surface 9 to reduce frictional resistance, and to prevent rust and corrosion on the steel plate 8 and the steel plate 10. Therefore, the gap h is filled with a lubricant that also serves as rust preventive, such as heat-resistant oil. To prevent the lubricant from dripping when the lubricant is filled, the lower plate 3 of the steel material has a saucer protruding outward. 11 is attached, and well-known caulking is applied to a portion through which the anchor bolt 2 and a flexible connecting member to be described later penetrate this receiving tray 11 so as to prevent the lubricant from leaking.

The arrangement of the spherical convex surface 7 and the concave surface 9 provided on the steel plate 8 and the steel plate 10 at each stage to be stacked as described above is provided on the steel plate 8 and the steel plate 10 at the upper stage. The convex surface 7 and the concave surface 9 are indicated by solid lines, and the convex surface 7 and the concave surface 9 provided on the lower steel plate 8 and the steel plate 10 are indicated by dotted lines. As shown in FIG. Concave 9
The upper surface steel plate 8, the steel plate 10 and the lower steel plate 8 and the steel plate 10 have convex surfaces 7 and 7 such that the convex surface 7 and the concave surface 9 indicated by one dotted line are located at the center of By shifting the position of the concave surface 9 to increase the number of points that receive the compressive force, and by combining the stack of the multi-stage steel plate 8 and the steel plate 10 with each other, the compressive force is distributed to a large number of points, so that the compressive force is reduced. With the steel plate 8 and the steel plate 10 isolated from each other, the convex surface 7 smoothly sways inside the concave surface 9, and when a sharp compressive force acts on each convex surface 7, a large number of The compressive stress is absorbed by the deformation strain of the convex surface 7.

In principle, the steel plate 8 and the steel plate 10 constituting the seismic isolation mechanism A may be one, but a spherical convex surface 7 is formed on both sides of one steel plate 8. Or, it is difficult to form the concave surfaces 9 on both sides of one steel plate 10. Therefore, the steel plate 8 and the steel plate 10 have two steel plates 8a as shown in FIG. The steel plate 8b and the steel plate 10a and the steel plate 10b are divided into the steel plate 8a and the steel plate 8b, and the convex surface 7 is formed respectively, and the steel plate 10a and the steel plate 10b are respectively formed with the concave surface 9. After that, the two steel plates 8a and 8b and the steel plate 10a and the steel plate 10b are overlapped with each other and the peripheral edges thereof are joined by welding 11 to be integrated with each other. Steel plate 8
The steel plate 10 having the concave surfaces 9 on both sides can be easily formed. The lowermost one and the uppermost one of the steel plates 10 may be used by stacking two sheets as described above, but one sheet is not functionally necessary, so that the steel sheet shown in FIG. Only one plate 10 is used as shown.

Next, reference numeral 12 denotes a flexible connecting member. As shown in FIG. 1, a large number of rings 13 are formed in series so as to form a chain which provides flexibility without directivity. The bolts 14 are respectively connected to the upper and lower rings 13 used, and the holes made in the lower plate 3 fixing these bolts 14 to the foundation 1 and the holes made in the upper plate 6 of the steel material fixed to the building 4. And a nut 15 is screwed into a portion of the steel lower plate 3 and the steel upper plate 6 that is exposed to the outside to connect the steel lower plate 3 and the steel upper plate 6 together. A notch 16 is provided in the building 4 and the foundation 1 in order to attach or replace the flexible connecting member 12, and the nut 15 can be screwed into and removed from the bolt 14 in the notch 16. Make it easy. However, some structures have no pull-out force due to their structure, and thus the connecting member 12 may not be used for such structures.

In the seismic isolation structure of the building constructed as described above, when the steel plate 10 fixed to the foundation 1 moves in the direction shown by the arrow in FIG.
Tries to push up the convex surface 7 by moving it sideways by L with respect to the convex surface 7 of the upper steel plate 8. However, the load of the building 4 acts on the upper steel plate 10 to apply a braking force to the steel plate 10, so that the steel plate 10 stops. Then, the steel plate 8 on the upper side causes a movement in the arrow direction to cause the convex surface 7 to lie sideways in the concave surface 9 of the steel plate 10 on the upper side by L, and stops when the braking force due to the load of the building acts. Then, the lateral wandering distance during this period is L + L = 2L, and the size of L changes in proportion to the difference between the radius r of the convex surface 7 and the radius R of the concave surface 9 and the lateral movement force that acts. If the value is set so as to sufficiently absorb the maximum amplitude of the horizontal vibration predicted in consideration of the number of stacking steps of the steel plate 8 and the steel plate 10, etc., the lateral sloping is one after another. Of the steel plate 8 and the steel plate 8 are transmitted to the steel plate 8 and the steel plate 8, and the convex surfaces 7 and the concave surfaces 9 of the steel plate 8 cause the same lateral stumbling as described above. When the number of stacking steps is n, the total lateral crossing distance n times L is obtained. If you put Ri distance is set larger than the maximum amplitude of the roll to be predictive of this following skid seismic isolation mechanism A is the amplitude
Since it does not reach the upper plate 6 of the steel material to which the building 4 is fixed, the building 4 is not affected by the earthquake,
Therefore, damage to the building 4 is prevented. Meanwhile,
If the amount of sideways slip is larger than the forecast, it means that the estimated amount of slippage has been absorbed, so it is treated as an earthquake with a smaller seismic intensity.

On the outside of the seismic isolation mechanism A, a flexible connecting member 12 for connecting the lower plate 3 of steel and the upper plate 6 of steel.
Is installed and the strength of the single unit and the number of installations are set so that the required drag force can be obtained when the pulling force is generated by the earthquake. The ring 13 is connected as a member having flexibility. When a chain is used, the chain flexes freely in the force acting direction, and each ring 13 has a function of incorporating a deformation stress and flexibly absorbing the tensile force. Further, if a pulling force is generated due to an insufficient amount of lateral movement of the seismic isolation mechanism A, the connecting member 12 acts not only to damp this force but also to cause lateral movement. When pulling force of pulling out occurs before, it works effectively against this. Although the lower plate 3, the upper plate 6 and the plates 8 and 10 are made of steel in the above-mentioned embodiment, the present invention is not limited to this, and the same strength as the above steel can be obtained. If it exists, it may be formed of a reinforced resin material, for example.

As described above, the seismic isolation structure in the building according to the present invention uses the seismic isolation mechanism in which a large number of sets of plates are stacked with a slight gap by engaging the spherical convex surface and the concave surface. When the foundation of a building vibrates due to an earthquake, a large number of plates of the seismic isolation mechanism move to follow this and receive a resistance that acts as a braking force. It is possible to expect a nearly perfect effect in preventing damage of the earthquake. Moreover, according to the present invention, if the lower plate and the upper plate are connected by a flexible connecting member outside the seismic isolation mechanism, the vertical direction of the earthquake Even if pull-out force acts on the seismic isolation mechanism due to shaking, the coupling member receives this and the seismic isolation mechanism is protected, and the coupling member freely follows the lateral vibration of the earthquake and is connected without damage. If you keep the function and give the chain flexibility, The transfer resistance can also be used in the vibration damping. This has the effect.

[Brief description of drawings]

FIG. 1 is a front view of a seismic isolation structure in a building according to the present invention.

FIG. 2 is a plan view in which a part of the building, the upper board, and the seismic isolation mechanism is cut away.

FIG. 3 is a partially enlarged vertical side view showing the structure of the seismic isolation mechanism of the above.

FIG. 4 is an enlarged vertical sectional front view showing a normal engagement state of the convex surface of one plate and the concave surface of the other plate of the seismic isolation mechanism in the normal state.

FIG. 5 is an enlarged vertical sectional front view showing displacement of engagement between the convex surface and the concave surface due to an earthquake.

FIG. 6 is an explanatory diagram showing a planar arrangement relationship between a convex surface and a concave surface of two sets of plates constituting the seismic isolation mechanism.

[Explanation of symbols] 1 Foundation 3 Steel lower plate 4 Building 6 Steel upper plate A Seismic isolation mechanism 7 Convex surface 8 Steel plate 9 Concave surface 10 Steel plate 12 Flexible connecting member

Claims (2)

[Claims] 1. In a seismic isolation structure for a building, etc., in which a seismic isolation mechanism is installed between a lower panel fixed to a foundation and an upper panel fixed to a building, the seismic isolation mechanism has a large number of plates. Characterized in that the spherical convex surface provided on the plate is engaged with the spherical concave surface provided on the other plate with a radius larger than the spherical convex surface and superposed so that there is a slight gap between the plates. Seismic isolation structure for buildings. 2. A spherical convex surface provided on one plate with a large number of plates is engaged with a spherical concave surface provided on the other plate with a radius larger than the spherical convex surface so that a slight gap exists between the plates. 2. A flexible connecting member for connecting an upper board fixed to a building and a lower board fixed to a foundation is arranged outside a seismic isolation mechanism having a structure superposed on each other. Seismic isolation structure for buildings. [0001]