JP2000054684A - Base isolation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a function by fixing a sliding strip on one of upper and lower part structures and fixing a laminated rubber support member free to slide along the sliding strip on the other. SOLUTION: A base isolation device is constituted of a laminated rubber support member 2 fixed on a continuous footing 1 and a sliding plate 4 fixed on a lower surface of a building wall 3 in the direction orthogonal to the footing 1. Thereafter, the support 2 is made free to slide on the plate 4 by sticking a sliding material 5 of Teflon etc., on an upper surface, the plate 4 is formed into a band shape out of stainless steel etc., so as to provide desired friction damping force, and a frame guide to guide sliding of the support 2 in the longitudinal direction is provided on a peripheral edge part. At the time of an earthquake, the support 2 slides in the longitudinal direction of the plate 4 when the wall 3 is displaced in the longitudinal direction of the plate 4, and the support 2 absorbs the displacement by elastic force when the wall 3 is displaced in the direction intersecting the longitudinal direction of the plate 4. Consequently, it is possible to adjust base isolation performance in the horizontal direction and to easily set it in a narrow part of the continuous footing etc., when a laminated rubber support and a sliding support are combined by arranging plural numbers of the base isolation device in the proper directions.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a seismic isolation device interposed between an upper structure and a lower structure in various seismic isolation structures.

[0002]

2. Description of the Related Art In recent years, in various structures, a seismic isolation device is interposed in a foundation portion, a middle level, and the like of the structure to attenuate vibrations that are likely to propagate from the ground to the structure due to an earthquake or the like. Various types of seismic isolation structures have been developed to reduce the stress and deformation generated in the structural body.
Conventionally, seismic isolation devices used for such seismic isolation structures are roughly classified into those of a laminated rubber bearing type and those of a sliding bearing type or a rolling bearing type.

Here, a seismic isolation device using a laminated rubber bearing is:
Generally, a thin steel plate and rubber sheet are alternately superimposed in multiple layers to provide a large load-bearing capacity and a horizontal displacement capacity, and the high-elastic rubber absorbs the horizontal relative displacement generated during an earthquake. The seismic force is reduced by increasing the natural period of the structure.

On the other hand, the above seismic isolator of the sliding bearing system is a flat sliding plate mounted on a lower structure such as a foundation, fixed to the lower surface of the upper structure, and slidably mounted on the sliding plate. The sliding material slides on the sliding plate when the lower structure is displaced horizontally during an earthquake. The resulting frictional force attenuates the horizontal seismic force acting on the superstructure, thereby ensuring the soundness of the superstructure.

[0005]

By the way, when a structure is to be made seismically isolated by such a seismic isolation device, a construction method in which a plurality of types of seismic isolation devices described above are used in combination is usually employed. In particular, when a seismic isolation device with a laminated rubber bearing and a seismic isolation device with a sliding bearing are combined, an appropriate coefficient of friction and restoring force can be obtained, and the natural period must be longer. It is known that an effective seismic isolation structure can be realized.

However, when the seismic isolation device of the laminated rubber bearing and the seismic isolation device of the sliding bearing are combined as described above, the number of seismic isolation devices to be interposed between the upper and lower structures increases. As a result, there has been a problem that construction is complicated and leads to an increase in cost. Moreover, in order to have the same seismic isolation performance in any horizontal direction, depending on the structure,
Even when there is a request to provide seismic isolation performance biased in one of the X and Y directions, there is also a problem that it cannot be easily coped with.

[0007] Particularly, in a seismic isolation device using a sliding bearing, the sliding member fixed to the upper structure slides on a flat sliding plate fixed to the lower structure. As it is necessary to use a square or circular shape in order to secure the displacement amount assumed at the time of the earthquake in both the X and Y directions in the horizontal plane, and as a result the slip plate becomes large, Correspondingly, there is a problem that the mounting portion of the slide plate in the lower structure such as the foundation must be set to a large size.

[0008] For this reason, especially in a structure using a cloth foundation such as a house, it is difficult to attach the above-mentioned sliding plate made of a large square plate or a circular plate to the upper surface of the cloth foundation. Only at the place where the slide plate of the above-mentioned base part is attached, it is necessary to form a separate large-area attachment part or to make structural changes such as making it an independent foundation, which significantly increases the cost of the structure itself. There was a problem of inviting.

The present invention has been made to effectively solve the problems of the conventional seismic isolation device using a sliding bearing, and has the advantage of combining a laminated rubber bearing and a sliding bearing, and has a horizontal seismic isolation method. It is an object of the present invention to provide a seismic isolation device that can change its performance and can be easily installed even in a narrow portion such as a structure based on a cloth foundation.

[0010]

According to a first aspect of the present invention, there is provided a seismic isolation device according to the present invention, in which a strip-shaped slip plate fixed to one of the upper and lower structures and a second plate of the upper and lower structures are fixed. A laminated rubber bearing member, and the laminated rubber bearing member is slidably disposed along the sliding plate by providing a sliding material on a tip end surface thereof. Things.

Here, as the above-mentioned sliding plate, guides for guiding the laminated rubber bearing member are provided on both sides in the sliding direction in order to surely slide the laminated rubber bearing member along the sliding plate. Is preferred.

In the seismic isolation device of the first aspect, when an upper structure is relatively displaced in the longitudinal direction of the slide plate when an earthquake occurs, the laminated rubber bearing member slides along the slide plate. On the other hand, when the upper structure is relatively displaced in a direction intersecting with the longitudinal direction of the slide plate, this is absorbed by the elastic force of the laminated rubber bearing member.

Therefore, in order for the seismic isolation device installed in one place to function as a sliding bearing and a laminated rubber bearing depending on the direction of relative displacement of the upper and lower structures, a plurality of the seismic isolation devices are connected to each other. By changing the longitudinal direction of the slide plate and installing it at multiple locations, one type of seismic isolation device
The seismic isolation effect of the laminated rubber bearing and the sliding bearing can be obtained.

By appropriately adjusting the number of the sliding plates in the longitudinal direction, it is possible to easily construct a seismic isolation structure whose seismic isolation performance changes depending on the direction. Further, according to the above seismic isolation device, since the slide plate is formed in a strip shape allowing the movement of the laminated rubber bearing member in only one direction, the mounting portion of the structure for fixing the slide plate is also reduced. Becomes possible. As a result, it is possible to easily apply the present invention to a structure having a narrow attachment portion such as a cloth foundation.

[0015]

1 to 3 show one embodiment of a seismic isolation device according to the present invention, and FIG. 4 shows an example of the arrangement of the seismic isolation device in a seismic isolation structure. It is. 1 to 3, this seismic isolation device includes a laminated rubber bearing member 2 fixed to a cloth foundation (lower structure) 1 and a building wall (upper structure) 3 extending in a direction orthogonal to the cloth foundation 1. And a slide plate 4 fixed to the lower surface.
Here, the laminated rubber bearing 2 has a sliding material 5 such as Teflon, fluororesin (PTFE) material, polyacetal or the like on its upper surface.
Are slidably provided on the surface of the slide plate 4 by being integrally attached.

On the other hand, the sliding plate 4 is a belt-shaped member, and its surface is made of stainless steel, chrome plating, or the like so that a desired friction damping force is obtained when the sliding member 5 slides. . As shown in FIG. 2, a frame guide 4a for guiding the sliding of the laminated rubber bearing member 2 in the longitudinal direction is integrally fixed to the peripheral portion of the slide plate 4.

FIG. 4 shows an arrangement example of the seismic isolation device in the seismic isolation structure 10. In this seismic isolation structure 10, six of the eight sets of seismic isolation devices are attached to the building wall 3 with the longitudinal direction of the sliding plate 4 pointing up and down in the figure. Two sets of seismic isolation devices are mounted so that the longitudinal direction of the slide plate 4 is oriented in the horizontal direction in the figure.

Next, the operation of the seismic isolation device having the above configuration will be described. In the above building, when an earthquake occurs, first, when the upper structure is relatively displaced in the longitudinal direction of the slide plate 4, the laminated rubber bearing member 2 is moved to the frame guide 4a.
The slider slides along the longitudinal direction of the slide plate 4 between them. On the other hand, when the upper structure is relatively displaced in a direction intersecting with the longitudinal direction of the slide plate 4, the laminated rubber bearing member does not slip but absorbs the elastic force.

Accordingly, for example, in the case of the seismic isolation structure 10 shown in FIG. 4, when the upper structure is displaced vertically in the figure during an earthquake, six sets of seismic isolation devices reduce the seismic force by sliding bearings. At the same time, two sets of seismic isolation devices absorb this with laminated rubber bearings. As a result, slip bearings predominate as seismic isolation performance. On the other hand, when the upper structure is relatively displaced in the horizontal direction in the figure, two sets of seismic isolation devices reduce the seismic force by sliding bearings, and six sets of seismic isolation devices reduce this by laminated rubber bearings. Absorb. As a result, laminated rubber bearings become dominant in seismic isolation performance.

As described above, according to the seismic isolation device having the above-described structure, the seismic isolation device installed at one location exerts the function of the sliding bearing and the laminated rubber bearing depending on the relative displacement direction. By installing a plurality of the above-mentioned seismic isolation devices at a plurality of locations by changing the longitudinal direction of the slide plate with each other, the seismic isolation effect of the laminated rubber bearing and the slip bearing can be obtained by one type of seismic isolation device. As shown in FIG. 4, by appropriately adjusting the number of slide plates in the longitudinal direction, it is possible to easily construct the seismic isolation structure 10 whose seismic isolation performance changes depending on the direction of the seismic force.

According to the above seismic isolation device, the sliding plate 4
Is formed in the shape of a strip that allows the movement of the laminated rubber bearing member 2 only in one direction, so that the mounting portion of the structure for fixing the same can be made small. As a result, it is possible to easily apply the present invention to a structure having a narrow attachment portion such as a cloth foundation.

[0022]

As described above, according to the first aspect of the present invention, a strip-shaped sliding plate is fixed to one of the upper and lower structures, and the laminated rubber bearing member is mounted to the other of the upper and lower structures. In addition to being fixed, a sliding member is provided on the tip end surface of the laminated rubber bearing member and is slidably disposed along the sliding plate. Therefore, by arranging this seismic isolation device in an appropriate direction, the laminated rubber bearing is provided. Has the advantage of combining with a sliding bearing,
In addition to being able to change the seismic isolation performance in the horizontal direction, it is also possible to easily install the device in a narrow portion such as a structure based on a cloth foundation.

[Brief description of the drawings]

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

FIG. 2 is a cross-sectional view in a direction orthogonal to the slide plate of FIG.

FIG. 3 is a perspective view showing a state where the seismic isolation device of FIG. 1 is attached to a foundation of a building.

4 is a diagram showing an example of the arrangement of the seismic isolation device of FIG. 1 in a seismic isolation structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cloth foundation (substructure) 2 Laminated rubber bearing member 3 Building wall (superstructure) 4 Slip board 5 Slip material

Claims (1)

[Claims] 1. A belt-shaped slide plate fixed to one of the upper and lower structures, and a laminated rubber bearing member fixed to the other of the upper and lower structures, and the laminated rubber bearing member comprises: A seismic isolation device, characterized in that a slip member is provided on a tip end surface thereof and is slidably disposed along the slip plate.