JP7261377B2 - Seismic isolation structure - Google Patents

Description

Article 30, Paragraph 2 of the Patent Act applies July 28, 2018 Published by Steel Structure Publishing Co., Ltd. Steel structure technology Vol.

The present invention relates to a seismic isolation structure.

A seismic isolation structure such as an arena or a stadium is known in which a roof structure covering a stand portion is supported by laminated rubber bearings (see, for example, Non-Patent Document 1 and Patent Documents 1 and 2).

JP-A-8-326351 JP 2002-047827 A

Tatsuya Kataoka, Yasuhiko Asaoka, Kazuaki Abe, "Steel Structure Technology", August 2018 issue, VOL. 31, NO. 363, Steel Construction Publishing Co., Ltd., published in August 2018, p. 058-059

By the way, roof structures of arenas, stadiums, and the like are large in size and thus tend to be heavy. Therefore, there is a possibility that the cross-sectional area of the struts that support the roof frame will increase.

As a countermeasure against this, it is conceivable to support the roof structure not only by the struts but also by the stands via laminated rubber bearings.

However, if the stand section supports the roof frame via the laminated rubber bearing, horizontal force is transmitted from the roof frame to the stand section during an earthquake. Therefore, when designing the stand, it is necessary to take into account the horizontal force transmitted from the roof structure during an earthquake, which may complicate the design of the stand.

SUMMARY OF THE INVENTION In view of the above facts, it is an object of the present invention to reduce the horizontal force transmitted from the roof structure to the stand during an earthquake.

The seismic isolation structure according to claim 1 is arranged between a plurality of struts arranged on the outer periphery, a plurality of laminated rubber bearings respectively provided on top of the plurality of struts, and the adjacent struts. a slide bearing provided on the upper part of the stand; and a roof frame supported by the column via the laminated rubber bearing and supported by the stand via the slide bearing. , provided.

According to the seismic isolation structure of claim 1, a plurality of struts are arranged on the outer periphery of the seismic isolation structure. Laminated rubber bearings are provided on top of these struts, respectively. Also, a stand portion is arranged between the adjacent support portions. A slide bearing is provided in the upper part of this stand part.

Here, the roof frame is supported by the pillars via laminated rubber bearings and supported by the stand via sliding bearings. This makes the roof structure seismically isolated. Therefore, the seismic performance of the roof frame is improved.

Also, the weight (vertical load) of the roof frame is supported by a plurality of struts and stands. Therefore, in the present invention, the cross-sectional area of the struts can be reduced compared to the case where the weight of the roof load is supported only by the struts.

Furthermore, as described above, the roof frame is supported by the struts via the laminated rubber bearings and supported by the stand via the sliding bearings. Therefore, the horizontal force acting on the roof frame during an earthquake is mainly transmitted to the column via the laminated rubber bearing, and is basically not transmitted to the stand. Therefore, the horizontal force transmitted from the roof frame to the stand during an earthquake is reduced, thereby simplifying the design of the stand.

A seismic isolation structure according to claim 2 is the seismic isolation structure according to claim 1, in which the support columns are made of steel.

According to the seismic isolation structure according to claim 2, the column is made of steel. As a result, it is possible to shorten the construction period for erecting the pillars.

The base isolation structure according to claim 3 is the base isolation structure according to claim 2, wherein the stand section is made of concrete, and the pillar section and the stand section are structurally integrated. be.

According to the seismic isolation structure according to claim 3, the stand section is made of concrete. On the other hand, the strut part is made of steel. The strut portion and the stand portion are structurally integrated. As a result, for example, an expansion joint or the like provided between the stand portion and the strut portion can be omitted. In addition, it is possible to easily secure a waterproof property between the stand portion and the support portion.

The base isolation structure according to claim 4 is the base isolation structure according to any one of claims 1 to 3, wherein the support columns are arranged at the four corners.

According to the seismic isolation structure of claim 4, the support columns are arranged at the four corners of the seismic isolation structure. Here, the plurality of pillars bear not only the weight of the roof frame but also the horizontal force acting on the roof frame during an earthquake, so they are designed to have high rigidity and high yield strength. By arranging high-rigidity and high-yield-strength struts at the four corners of the seismic isolation structure in this way, it is possible to reduce the eccentricity of the seismic isolation structure while efficiently supporting the roof structure with multiple struts. can be done.

As described above, according to the present invention, it is possible to reduce the horizontal force transmitted from the roof structure to the stand during an earthquake.

1 is an elevation view showing a seismic isolation structure according to one embodiment; FIG. FIG. 2 is a plan view showing the seismic isolation structure shown in FIG. 1; 3 is a cross-sectional view taken along line 3-3 of FIG. 1; FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. 1; FIG.

Hereinafter, a seismic isolation structure according to one embodiment will be described with reference to the drawings.

(Seismic isolation structure)
FIG. 1 shows a seismic isolation structure 10 according to this embodiment. The seismic isolation structure 10 is, for example, a large space structure (large space building) such as an arena or a stadium. The seismic isolation structure 10 includes a plurality of core frame portions (core frame portions) 20 , a plurality of stand portions (stand portions) 30 and a roof structure 40 . Note that the core frame portion 20 is an example of a support portion.

(core frame part)
As shown in FIG. 2, the seismic isolation structure 10 is formed in a rectangular shape in plan view. At the four corners (corners) of the seismic isolation structure 10, core frame portions 20 made of steel are respectively provided. These core frame portions 20 support the weight (long-term load) of the roof frame 40 and bear the horizontal force (short-term load) acting on the roof frame 40 during an earthquake.

The core frame portion 20 is formed in a triangular shape in plan view by combining a plurality of frames 22 . Each frame 22 has adjacent steel columns 24 and steel beams 26 that span the adjacent steel columns 24 . In addition, the frame 22 is provided with braces (anti-earthquake braces) not shown. Thereby, the rigidity and strength of the core frame portion 20 are enhanced. Note that braces can be omitted.

(Stand part)
Stand portions 30 are provided between adjacent core frame portions 20, respectively. The plurality of stand portions 30 support the weight of the roof frame 40 together with the plurality of core frame portions 20 . Each stand portion 30 is made of reinforced concrete. Further, each stand portion 30 is arranged over the adjacent core frame portions 20 . Furthermore, each stand part 30 is arranged so as to surround the central space 12 of the seismic isolation structure 10 . The central space 12 is provided with, for example, a stadium, a stage, and the like.

The stand part 30 is formed in a rectangular shape in plan view by combining a plurality of frames 32 . The frame 32 has adjacent concrete pillars 34 and concrete beams 36 constructed over the adjacent concrete pillars 34 . Also, the stand portion 30 is formed in a stepped shape that rises toward the outer periphery of the seismic isolation structure 10 .

The frames 22 and 32 of the core frame portion 20 and the stand portion 30 that are adjacent to each other on the outer periphery of the seismic isolation structure 10 are structurally connected to form an integral frame. Specifically, the steel beams 26 of the frame 22 are joined (rigidly joined) to the beam-column joints of the concrete columns 34 of the frame 32 . A roof frame 40 (see FIG. 1) covering the central space 12 is provided above the stand portion 30 and the core frame portion 20 .

(roof frame)
As shown in FIG. 1, the roof structure 40 is of steel construction. Moreover, the roof frame 40 is formed in a rectangular shape in plan view. This roof frame 40 is formed by combining a plurality of truss frames 42 . The truss frame 42 has an upper chord member 42A and a lower chord member 42B that face each other in the vertical direction, and bundle members 42C and diagonal members 42D that connect the upper chord member 42A and the lower chord member 42B.

As shown in FIG. 3 , the roof frame 40 is supported by each core frame portion 20 via multiple laminated rubber bearings 60 . Specifically, a receiving portion 62 is provided on each of the steel columns 24 arranged on the outer periphery of the seismic isolation structure 10 .

The receiving portion 62 extends from the upper portion of the steel column 24 toward the inner side of the seismic isolation structure 10 . Also, the tip of the receiving portion 62 is supported by a diagonal member 64 . Laminated rubber bearings 60 are installed on the receiving portions 62 respectively.

The laminated rubber bearing 60 is made of, for example, laminated rubber containing a lead plug or natural rubber-based laminated rubber. The lower flange portion 60L of the laminated rubber bearing 60 is joined to the receiving portion 62 by bolts or the like (not shown).

On the other hand, on the upper flange portion 60U of the laminated rubber bearing 60, the bundle 42C of the roof frame 40 is placed. The bundle 42C is joined to the upper flange portion 60U of the laminated rubber bearing 60 by bolts (not shown) or the like. The laminated rubber bearing 60 supports the roof frame 40 so as to be horizontally displaceable with respect to the core frame portion 20 . Further, the horizontal force acting on the roof frame 40 during an earthquake is transmitted to the core frame portion 20 via the laminated rubber bearings 60 .

The core frame portion 20 is provided with a seismic isolation damper (not shown). The seismic isolation damper connects the core frame portion 20 and the roof frame 40 . This attenuates the horizontal displacement of the roof frame 40 during an earthquake. Note that the seismic isolation damper can be omitted.

As shown in FIG. 4 , the roof frame 40 is supported by the stand section 30 via a plurality of sliding bearings 70 . Specifically, the concrete pillars 34 arranged on the outer periphery of the seismic isolation structure 10 are each provided with a receiving portion 72 .

The receiving portion 72 extends from the upper portion of the concrete pillar 34 toward the inner side of the seismic isolation structure 10 . Further, the receiving portion 72 is supported from below by a rib-like wall portion 74 . A slide bearing 70 is mounted on each of these receiving portions 72 .

The sliding bearing 70 is, for example, a low-friction elastic sliding bearing. The sliding bearing 70 has a sliding plate 70A fixed to the receiving portion 72, and a sliding body 70B fixed to the lower end portion of the bundle 42C of the roof frame 40 and slidably mounted on the sliding plate 70A. are doing. The sliding bearing 70 supports the roof frame 40 so as to be horizontally displaceable with respect to the stand portion 30 .

Further, the slide bearing 70 cuts the horizontal edge between the roof frame 40 and the stand portion 30 . As a result, the horizontal force acting on the roof frame 40 during an earthquake is not transmitted to the stand portion 30 but is transmitted to the core frame portion 20 via the multiple laminated rubber bearings 60 .

Note that the stand portion 30 is provided with a rolling bearing (not shown) that resists the pull-out force acting on the roof frame 40 due to the wind load. The rolling bearing is, for example, a linear motion rolling bearing. This rolling bearing connects the stand portion 30 and the roof frame 40 . Note that the rolling bearings may be provided as necessary, and can be omitted as appropriate.

(action)
Next, the operation of this embodiment will be described.

As shown in FIG. 2 , a plurality of core frame parts 20 are arranged around the outer periphery of the base isolation structure 10 . Laminated rubber bearings 60 (see FIG. 3) are provided on the upper portions of these core frame portions 20, respectively. A stand portion 30 is arranged between adjacent core frame portions 20 . A slide bearing 70 (see FIG. 4) is provided on the upper portion of the stand portion 30 .

Here, the roof frame 40 is supported by the core frame portion 20 via the laminated rubber bearings 60 and supported by the stand portion 30 via the sliding bearings 70 . Thereby, the roof frame 40 is seismically isolated. Therefore, the seismic performance of the roof frame 40 is improved.

Also, the weight of the roof frame 40 is supported by a plurality of core frame portions 20 and stand portions 30 . Therefore, in this embodiment, the cross-sectional area of the core frame portion 20 can be reduced compared to the case where the weight of the roof frame 40 is supported only by the core frame portion 20 .

Further, as described above, the roof frame 40 is supported by the core frame portion 20 via the laminated rubber bearings 60 and supported by the stand portion 30 via the sliding bearings 70 . Therefore, the horizontal force acting on the roof frame 40 during an earthquake is mainly transmitted to the core frame portion 20 via the laminated rubber bearing 60 and is basically not transmitted to the stand portion 30 . Therefore, since the horizontal force transmitted from the roof frame 40 to the stand part 30 during an earthquake is reduced, the design of the stand part 30 is simplified.

Moreover, the core frame portions 20 are arranged at the four corners of the seismic isolation structure 10 . Here, as described above, the plurality of core frame portions 20 bear not only the weight of the roof frame 40 but also the horizontal force acting on the roof frame 40 during an earthquake, so they are designed to have high rigidity and high yield strength. By arranging the core frame portions 20 with high rigidity and high yield strength at the four corners of the seismic isolation structure 10 in this manner, the roof structure 40 is efficiently supported by the plurality of core frame portions 20, and the seismic isolation structure 10 eccentricity can be reduced.

Further, the core frame portion 20 is made of steel. As a result, in this embodiment, the deformation performance of the core frame portion 20 that bears the horizontal force of the roof frame 40 during an earthquake is enhanced compared to the case where the core frame portion 20 is made of reinforced concrete. Therefore, the seismic performance of the seismic isolation structure 10 is improved.

Furthermore, in this embodiment, the construction period for erecting the core frame portion 20 can be shortened compared to the case where the core frame portion 20 is made of reinforced concrete.

On the other hand, the stand part 30 is made of reinforced concrete. Thereby, in this embodiment, the vertical rigidity of the stand part 30 is increased compared with the case where the stand part 30 is steel-framed. Therefore, for example, when a concert is held in the seismic isolation structure 10, the vibration of the stand section 30 due to jumping of the audience or the like is reduced. As a result, the vibrations propagated to neighboring facilities of the seismic isolation structure 10 are reduced.

Also, the stand portion 30 and the core frame portion 20 are structurally integrated. Thereby, for example, an expansion joint or the like provided between the stand portion 30 and the core frame portion 20 can be omitted. In addition, it is possible to easily secure water stopping properties between the stand portion 30 and the core frame portion 20 .

(Modification)
Next, a modification of the above embodiment will be described.

In the above embodiment, the frames 22 and 32 of the adjacent core frame portion 20 and stand portion 30 are structurally connected to form an integral frame. However, the frames 22 and 32 of the core frame portion 20 and the stand portion 30 do not have to be integrally connected structurally. In this case, for example, the frames 22 and 32 of the core frame portion 20 and the stand portion 30 may be connected by vibration dampers to absorb seismic energy.

When the frames 22 and 32 of the adjacent core frame portion 20 and the stand portion 30 are not structurally connected integrally, the frames 22 and 32 are appropriately connected by an expansion joint or the like, for example.

Further, in the above embodiment, the core frame portions 20 are arranged at the four corners of the seismic isolation structure 10 . However, the core frame part 20 may be arranged on the outer peripheral part other than the four corners of the seismic isolation structure 10 . At this time, the stand portion 30 is appropriately arranged between the adjacent core frame portions 20 .

In addition, in the above-described embodiment, the seismic isolation structure 10 is formed in a rectangular shape in plan view. However, the shape of the seismic isolation structure may be triangular or more polygonal in plan view, or may be circular or elliptical in plan view.

Further, in the above-described embodiment, the core frame portion 20 as an example of the strut portion is made of steel. However, the supporting column may be made of reinforced concrete, steel-reinforced concrete, or the like. Also, the shape and arrangement of the support can be changed as appropriate.

Further, in the above embodiment, the stand portion 30 is made of reinforced concrete. However, the stand may be made of steel-reinforced concrete or steel. Also, the shape and arrangement of the stand portion 30 can be changed as appropriate.

Furthermore, the seismic isolation structure 10 according to the above embodiment is applicable not only to arenas, stadiums, etc., but also to various seismic isolation structures.

Although one embodiment of the present invention has been described above, the present invention is not limited to such an embodiment, and one embodiment and various modifications may be used in combination as appropriate. It goes without saying that various aspects can be implemented without departing from the scope.

10 Seismic isolation structure 20 Core frame part (strut part)
30 stand part 40 roof frame 60 laminated rubber bearing 70 sliding bearing

Claims (4)

a plurality of struts arranged on the outer periphery;
a plurality of laminated rubber bearings respectively provided on the upper portions of the plurality of support columns;
a stand portion arranged between the adjacent strut portions;
a sliding bearing provided on the upper part of the stand;
a roof frame that is supported by the support via the laminated rubber bearing and supported by the stand via the sliding bearing;
Seismic isolation structure with The strut part is made of steel,
The seismic isolation structure according to claim 1. The stand portion is made of concrete,
The strut portion and the stand portion are structurally integrated,
The seismic isolation structure according to claim 2. The struts are arranged at four corners,
A seismic isolation structure according to any one of claims 1 to 3.

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