JP7333334B2 - Seismic isolation device - Google Patents

Description

The present invention relates to a seismic isolation device.

A conventional seismic isolation device includes a laminated structure in which hard materials and soft materials are alternately arranged in the vertical direction, and an end portion disposed in at least one of the upper and lower end regions of the laminated structure. There is one in which the widthwise outer edge of the hard material is extended to the outside in the widthwise direction from the central hard material arranged in the central region of the laminate structure (see, for example, Patent Document 1). According to the seismic isolation device described in Patent Document 1, even when the laminated structure is elastically deformed in the horizontal direction, the terminal hard material supports the central hard material, which causes buckling of the laminated structure. It is possible to suppress the local stress concentration that occurs in the portion on the compression side (the end region).

JP 2014-47926 A

On the other hand, the seismic isolation device increases the seismic isolation performance and protects the structure by lengthening the natural vibration period.

According to the seismic isolation device described in Patent Document 1, the greater the width of the terminal hard material, the greater the buckling improvement effect. However, if the width of the terminal hard material is too large, when the laminated structure undergoes large elastic deformation, the width direction outer edge of the terminal hard material is likely to separate from the soft material due to stress concentration, resulting in poor durability. There was room for improvement. Furthermore, the buckling improvement effect greatly depends on the width of the hard material at the upper and lower ends, but in the seismic isolation device described in Patent Document 1, there is a possibility that the natural vibration period of the structure is shortened.

SUMMARY OF THE INVENTION An object of the present invention is to provide a seismic isolation device that is excellent in buckling resistance and durability without impairing the required seismic isolation performance.

A seismic isolation device according to the present invention is a seismic isolation device provided with a laminated structure formed by alternately arranging hard materials and soft materials in a vertical direction, wherein the laminated structures are provided on an upper side and a lower side, respectively. a central region located between said two terminal regions and located between said central region and said terminal region and adjacent to said central region and said terminal region; two intermediate regions, wherein the hard material located in the end regions is at least one terminal hard material, and the hard material located in the central region is at least one central hard material. and the hard material arranged in the intermediate region is at least one intermediate hard material, and the widthwise outer edge of the terminal hard material is positioned outside the widthwise outer edge of the central hard material. and the widthwise outer edge of the intermediate hard material is positioned widthwise outside the widthwise outer edge of the central hard material and widthwise inside the widthwise outer edge of the terminal hard material; The ratio (W2/W1) of the width W2 between the widthwise outer edges of the central hard material to the width W1 between the widthwise outer edges of the hard material (W2/W1) is 0.6≦(W2/W1)≦0.97. According to the seismic isolation device according to the present invention, the seismic isolation device is excellent in buckling resistance and durability without impairing the required seismic isolation performance.

In the seismic isolation device according to the present invention, the plurality of intermediate hard materials are arranged in the intermediate region, and the width of the plurality of intermediate hard materials decreases from the terminal region side toward the central region side. It is preferable to be In this case, local stress concentration occurring in the end region can be further suppressed, and durability can be further improved.

In the seismic isolation device according to the present invention, it is preferable that a plurality of central hard materials are arranged in the central region, and widths of the plurality of central hard materials are the same. In this case, even if there are a plurality of central hard materials, the required seismic isolation performance can be exhibited more reliably.

In the seismic isolation device according to the present invention, a plurality of terminal hard materials are arranged in the terminal region, and the widths of the plurality of terminal hard materials are the same . In this case, the local stress concentration occurring in the end region can be further suppressed, and the buckling resistance and durability can be further improved.

In the seismic isolation device as a reference example , a plurality of terminal hard materials are arranged in the terminal region, and the width of the plurality of terminal hard materials increases from the central region side toward the terminal region side. can be

In the seismic isolation device according to the present invention, in a vertical cross-sectional view of the seismic isolation device, the end hard material adjacent to the intermediate hard material, the intermediate hard material, and the central hard material adjacent to the intermediate hard material , and an imaginary ridge formed by connecting the respective widthwise outer edges, the acute angle A formed with respect to the vertical direction can be 45° to 80°. In this case, buckling can be made difficult to occur.

In the seismic isolation device according to the present invention, the imaginary ridge line can be linear in a vertical cross-sectional view of the seismic isolation device. In this case, buckling can be made more difficult to occur.

In the seismic isolation device according to the present invention, the ratio (H3/H0) of the vertical height H3 of the intermediate region to the vertical height H0 of the laminated structure is 0.01 to 0.1. can do. In this case, the widthwise outer edge of the terminal hard material is less likely to separate from the soft material due to stress concentration, and durability is improved.

In the seismic isolation device according to the present invention, the outer surface shape of the laminated structure may be a combination of linear shapes in a vertical cross-sectional view of the seismic isolation device. In this case, the ratio of the soft material can be reduced compared to when the outer surface has a curved shape, so the seismic isolation performance can be improved.

ADVANTAGE OF THE INVENTION According to this invention, the seismic isolation apparatus excellent in buckling-resistant performance and durability can be provided, without impairing the required seismic isolation performance.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows roughly the seismic isolation apparatus which concerns on 1st Embodiment of this invention in a cross section containing an up-down direction. It is sectional drawing which shows roughly the seismic isolation apparatus which concerns on 2nd Embodiment of this invention in a cross section containing an up-down direction.

Hereinafter, seismic isolation devices according to various embodiments of the present invention will be described with reference to the drawings. In the following description, substantially the same items will be omitted by using the same reference numerals.

In FIG. 1, reference numeral 1A denotes a seismic isolation device according to the first embodiment of the present invention. A seismic isolation device 1A includes a laminated structure 10 . The laminated structure 10 is formed by arranging hard materials 11 and soft materials 12 alternately in the vertical direction. The seismic isolation device 1A has a central axis O extending in the vertical direction, and the central axis O can be erected along the vertical axis.

A lower plate 20 is fixed to the lower end of the laminated structure 10 . The lower plate 20 can be fixed to a foundation (not shown) that supports a structure (not shown) such as a building, bridge, house, or the like. An upper plate 30 is fixed to the upper end of the laminated structure 10 . The top plate 30 can be fixed to the structure, for example. In this embodiment, the lower plate 20 and the upper plate 30 are made of circular steel plates.

The hard material 11 is a rigid layer. In this embodiment, the hard material 11 consists of a circular metal plate, specifically a circular steel plate. In this embodiment, the soft material 12 is a circular elastic plate, specifically a circular rubber plate. In this embodiment, hard material 11 and soft material 12 have the same thickness. However, the thicknesses of the hard material 11 and the soft material 12 can be changed as appropriate. Furthermore, in this embodiment, the widthwise outer edge 11 e of the hard material 11 is covered with the outer layer 13 together with the soft material 12 . The outer layer 13 is a cylindrical rubber plate. However, the outer layer 13 can be omitted.

As shown in the dashed area in FIG. 1, the laminated structure 10 includes two end regions R1 located on the upper side and the lower side, a central region R2 located between the two end regions R1, and the central Between the region R2 and the terminal region R1, it is partitioned into the central region R2 and two intermediate regions R3 located adjacent to the terminal region R1. Here, the end region R1 is at least one of a virtual region continuing downward from the upper end of the laminated structure 10 and a virtual region continuing upward from the lower end of the laminated structure 10. area. Also, the central region R2 is a virtual region located in the center of the laminated structure 10 in the vertical direction. Furthermore, the intermediate region R3 is at least one of a virtual region continuing downward from the lower end of the upper terminal region R1 and a virtual region continuing upward from the upper end of the lower terminal region R1. A virtual area that does not include the central area R2.

For example, the terminal region R1, the central region R2, and the intermediate region R3 are respectively the vertical height H1 on one side of the terminal region R1 and the vertical height H1′ on the other side, the vertical height H2 of the central region R2, and the intermediate region It is defined by one vertical height H3 and the other vertical height H3' of R3. In this case, the vertical height H0 of the laminated structure 10 is defined by H0=H1+H1'+H2+H3+H3'. Specific examples are H1/H0 = 0.01 to 0.24, H1'/H0 = 0.01 to 0.24, H2/H0 = 0.5 to 0.96, H3/H0 = 0.01 to 0.24, and H3'/H0=0.01 to 0.24.

Furthermore, in the laminated structure 10 , the rigid material located in the terminal region R<b>1 is at least one terminal rigid material 111 . Further, in the laminated structure 10, the hard material arranged in the central region R2 is at least one central hard material 112. As shown in FIG. Furthermore, in the laminated structure 10 , the hard material arranged in the intermediate region R3 is at least one intermediate hard material 113 . The seismic isolation device 1A according to this embodiment has one end hard material as the end hard material 111 . Also, the seismic isolation device 1A has a plurality of (ten in this embodiment) central hard materials as the central hard materials 112 . In this embodiment, central rigid material 112 is the same central rigid material. Furthermore, the seismic isolation device 1A has one intermediate hard material as the intermediate hard material 113 .

In the laminated structure 10, the widthwise positional relationship among the widthwise outer edge 111e of the terminal hard material 111, the widthwise outer edge 113e of the middle hard material 113, and the widthwise outer edge 112e of the central hard material 112 is as follows. satisfies the relationship (1).

Widthwise outer edge 111e of terminal hard material 111>widthwise outer edge 113e of intermediate hard material 113>widthwise outer edge 112e of central hard material 112 (1)

In particular, the terminal rigid material 111 has a widthwise outer edge 111e which is located widthwise outwardly of the widthwise outer edge 112e of the central rigid material 112 in any case. For example, when there are a plurality of terminal hard materials 111, the widthwise outer edge 111e of the terminal hard material 111 located on the innermost widthwise side of the widthwise outer edge 111e is positioned on the widthwise outer side of the widthwise outer edge 112e of the central hard material 112. position. Furthermore, when there are a plurality of central hard materials 112, the widthwise outer edge 111e of the terminal hard material 111 located on the innermost widthwise side of the widthwise outer edges 111e is wider than the widthwise outer edge 112e of any of the central hard materials 112. direction outside. In addition, the intermediate hard material 113 has a widthwise outer edge 113e positioned widthwise outside the widthwise outer edge 112e of the central hard material 112 and widthwise inside the widthwise outer edge 111e of the terminal hard material 111 in any case. ing. For example, when there are a plurality of intermediate hard materials 113, the widthwise outer edge 113e of the intermediate hard material 113 whose widthwise outer edge 113e is positioned innermost in the widthwise direction is positioned outside the widthwise outer edge 112e of the central hard material 112 in the widthwise direction. position. Furthermore, when there are a plurality of central hard materials 112, the widthwise outer edge 113e of the intermediate hard material 113 located on the innermost side in the widthwise direction of the widthwise outer edges 113e is wider than the widthwise outer edge 112e of any of the central hard materials 112. direction outside. In addition, when there are a plurality of intermediate hard materials 113, the widthwise outer edge 113e of the intermediate hard material 113 located on the outermost widthwise outer side of the widthwise outer edge 113e is located widthwise inwardly of the widthwise outer edge 111e of the terminal hard material 111. position. Furthermore, when there are a plurality of terminal hard materials 111, the widthwise outer edge 113e of the intermediate hard material 113 located on the outermost widthwise outer side of the widthwise outer edge 113e is wider than the widthwise outer edge 111e of any of the terminal hard materials 111. direction inside.

Further, the width between the widthwise outer edges 111e of the terminal hard material 111 is W1 (hereinafter also referred to as "the width W1 of the terminal hard material 111"), and the width between the widthwise outer edges 112e of the central hard material 112 is W2. (hereinafter also referred to as “the width W2 of the central hard material 112”), the ratio α (=W2/W1) of the width W2 of the central hard material 112 to the width W1 of the terminal hard material 111 has the following relationship: (2) is satisfied.

0.6≦(W2/W1)≦0.97 (2)

In this embodiment, the hard material 11 is a circular plate. Further, in this embodiment, the terminal hard material 111, the intermediate hard material 113, and the central hard material 112 are coaxially arranged on the central axis O. In this embodiment, the width W1 of the terminal hard material 111, the width W2 of the central hard material 112, and the width W3 between the widthwise outer edges 113e of the intermediate hard material 113 (hereinafter also referred to as "the width W3 of the intermediate hard material 113"). is the diameter of the hard material 11; That is, in this embodiment, the ratio α of the width W2 of the central hard material 112 to the width W1 of the terminal hard material 111 is the ratio of the diameter φ2 of the central hard material 112 to the diameter φ1 of the terminal hard material 111 (φ2/φ1 ) can be replaced with

In addition, the hard material 11 is not limited to a circular plate, and a polygonal plate or the like may be employed. In this case, the width W1 of the terminal hard material 111, the width W2 of the central hard material 112, and the width W3 of the intermediate hard material 113 can be the diameter of the circumscribed circle of the hard material 11. FIG. Also, the ratio α (=W2/W1) is preferably 0.6 or more. More preferably, α=0.7 to 0.92. In this case, sufficient seismic isolation performance can be ensured. If there is more than one hard material, W1 is the maximum width of terminal hard material 111 and W2 is the minimum width of central hard material 112 .

Specific examples of the width W1 of the terminal hard material 111, the width W2 of the central hard material 112, and the width W3 of the intermediate hard material 113 are W2/W1=0.6 to 0.97 and W3/W1=0.61. ~0.96.

According to the seismic isolation device according to the present embodiment, since the terminal hard material 111 has the widthwise outer edge 111e located on the widthwise outer side of the widthwise outer edge 112e of the central hard material 112, the laminated structure 10 Even when the terminal hard material 111 supports the central hard material 112, the local hard material 111 supports the central hard material 112 and causes buckling of the laminated structure 10, which occurs in the compression side portion (terminal region R1). Stress concentration can be suppressed.

On the other hand, the inventors of the present application have confirmed that the buckling characteristic is improved when only the width W1 of the terminal hard material 111 is simply ensured to be large. However, simply increasing W1 shortens the natural vibration period of a structure such as a building. Therefore, as a result of diligent testing and research, the inventors of the present application found that when the width W1 of the terminal hard material 111 is secured large, the natural vibration period of the structure can be shortened by reducing the width W2 of the central hard material 112. I came to recognize that the phenomenon can be suppressed. Specifically, when the ratio α of the width W2 of the central hard material 112 to the width W1 of the terminal hard material 111 is 0.97 or less, the buckling characteristic is improved while maintaining a long natural vibration period of the structure. Confirmed to improve. Therefore, according to the seismic isolation device 1A according to the present embodiment, the ratio α of the width W2 of the central hard material 112 to the width W1 of the terminal hard material 111 is 0.97 or less, so the buckling performance is improved. However, the required seismic isolation performance is not impaired. Also, if the ratio α of the width W2 of the center hard material 112 to the width W1 of the terminal hard material 111 is less than 0.6, the width of the center hard material 112 becomes small, resulting in a decrease in buckling performance and load bearing capacity. On the other hand, if the ratio α of the width W2 of the central hard material 112 to the width W1 of the terminal hard material 111 is set to 0.6 or more, the effect of improving the buckling performance is obtained and the load bearing capacity is not lowered.

In addition, according to the seismic isolation device 1A according to the present embodiment, the intermediate hard material is added to the two intermediate regions R3 located adjacent to the central region R2 and the terminal region R1 between the central region R2 and the terminal region R1. 113 is arranged, and the intermediate hard material 113 has a widthwise outer edge 113e positioned widthwise outside the widthwise outer edge 112e of the central hard material 112 and widthwise inside the widthwise outer edge 111e of the terminal hard material 111. Therefore, even when the laminated structure 10 is largely elastically deformed, local peeling does not occur on the compressed side of the widthwise outer edge 111e of the terminal hard material 111 adjacent to the intermediate hard material 113 .

In short, the buckling resistance performance of the seismic isolation device 1A according to the present embodiment is improved when compared with a seismic isolation device having the same horizontal rigidity and α exceeding 0.97. Further, when compared with a seismic isolation device having the same width W1 of the terminal hard material 111 and α exceeding 0.97, the seismic isolation device 1A according to the present embodiment can have a longer natural vibration period. Furthermore, when compared with a seismic isolation device in which the width W2 of the central hard material 112 is the same and α exceeds 0.97, the seismic isolation device 1A according to the present embodiment has the width direction outer edge 111e of the end hard material 111 compressed. It is possible to suppress local peeling that occurs on the side.

Therefore, according to the seismic isolation device 1A according to the present embodiment, the seismic isolation device is excellent in buckling resistance and durability while maintaining the load bearing capacity without impairing the required seismic isolation performance.

By the way, as described above, in this embodiment, one terminal hard material 111 is included in the terminal region R1. Central region R2 includes a plurality of central hard materials 112 . In this embodiment, the widths W2 of the central rigid materials 112 are each the same. Intermediate region R3 includes one intermediate hard material 113 .

However, according to the invention, the isolation device 1 can have at least one terminal hard material as the terminal hard material 111 in the terminal region R1. In this case, the widthwise outer edge 111e of each terminal hard material 111 is located on the widthwise outer side of the widthwise outer edge 112e of the central hard material 112 . Furthermore, it is preferable that the width W1 of each terminal hard material 111 becomes smaller toward the middle region R3 side.

Also, the seismic isolation device 1 can have at least one central hard material as the central hard material 112 in the central region R2. In this case, each central rigid material 112 is preferably the same central rigid material.

Furthermore, the seismic isolation device 1 can have at least one intermediate hard material as the intermediate hard material 113 in the intermediate region R3. In this case, each intermediate hard material 113 is preferably positioned widthwise outside the widthwise outer edge 112e of the central hard material 112 and widthwise inside the widthwise outer edge 111e of the terminal hard material 111 . Further, it is preferable that the intermediate hard material 113 has a width W3 that decreases from the terminal region R1 side toward the central region R2 side.

Specific examples of the number N1 of terminal hard materials 111, the number N2 of central hard materials 112, and the number N3 of intermediate hard materials 113 include 1 to 10 for N1 and 1 to 3 for N3.

Here, referring to FIG. 1 , imaginary partition lines in a vertical cross-sectional view (a cross section including the central axis of the seismic isolation device) of each of the end region R1, the central region R2, and the intermediate region R3. Description will be made using L1A to L3A and virtual partition lines L1B to L3B.

The demarcation line L1A is a demarcation line that passes through the fixed surfaces of the lower plate 20 and the soft material 12 adjacent to the lower plate 20 . The dividing line L3A passes through the soft material 12 between the lower terminal hard material 111 and the intermediate hard material 113 adjacent to the terminal hard material 111, and divides the soft material 12 into upper and lower parts. . A demarcation line L2A is a demarcation line passing through the lower end surface of the central hard material 112 on the lowermost side.

The demarcation line L1B is a demarcation line passing through the fixing surface between the upper plate 30 and the soft material 12 adjacent to the upper plate 30 . The dividing line L3B is a dividing line passing through the soft material 12 between the upper terminal hard material 111 and the intermediate hard material 113 adjacent to the terminal hard material 111 and dividing the soft material 12 into upper and lower parts. A demarcation line L2B is a demarcation line passing through the upper end surface of the uppermost central hard material 112 .

The two terminal regions R1 are partitioned as follows. The lower end region R1 is demarcated by a demarcation line L1A and a demarcation line L3A. The upper end region R1 is demarcated by a demarcation line L1B and a demarcation line L3B.

Central region R2 is demarcated by demarcation line L2A and demarcation line L2B.

The two intermediate regions R3 are partitioned as follows. The lower intermediate region R3 is demarcated by demarcation lines L3A and L2A. The upper intermediate region R3 is demarcated by demarcation lines L3B and L2B.

In the seismic isolation device 1A according to this embodiment, a plurality of central hard materials 112 are arranged in the central region R2, and the width W2 of the plurality of central hard materials 112 is preferably the same. In this embodiment, as described above, the widths W2 of the plurality of central hard materials 112 are the same. In this case, even if there are a plurality of central hard materials 112, the required seismic isolation performance can be exhibited more reliably.

Further, in the seismic isolation device 1A according to the present embodiment, the ratio β (=H3/H0) of the vertical height H3 of the intermediate region R3 to the vertical height H0 of the laminated structure 10 is 0.01 to 0. .1. If β is less than 0.01, or if β exceeds 0.1, the effect of suppressing buckling is small. In this embodiment, β is a numerical value in the range of 0.01 to 0.1. Therefore, according to the present embodiment, it is possible to make it more difficult for buckling to occur.

The vertical height H2 of the central region R2 is preferably H2/H0=0.5 to 0.96. In this case, a sufficient seismic isolation function can be achieved. Further, in this case, in the laminated structure 10, H2 is (0.5 to 0.96)×H0 in the central region R2, and the vertical height H3 (H3′) of the intermediate region R3 is (0.5 to 0.96)×H0. 01 to 0.1)×H0 is defined as an intermediate region R3, and the region outside these regions is defined as a terminal region R1, and terminal hard materials 111, central hard materials 112 and intermediate hard materials 113 are arranged in these regions R1 to R3, respectively. It is preferable to let More preferably, H2 is 0.5 to 0.96×H0 in the middle region R2, H3 (H3′) is 0.01 to 0.1×H0 in the middle region R3, H1 (H1′) ), the region from 0.01 to 0.24×H0 is defined as the terminal region R1.

Next, in FIG. 2, reference numeral 1B denotes a seismic isolation device according to a second embodiment of the present invention. In this embodiment, the terminal region R1 includes a plurality of (two in this embodiment) terminal hard materials 111 . In this embodiment, the terminal hard material 111 is the same terminal hard material, and the width W1 of the terminal hard material 111 is the same. The central region R2 includes a plurality of (ten in this embodiment) central hard materials 112 . In this embodiment, the central rigid materials 112 are identical central rigid materials and the widths W2 of the central rigid materials 112 are each identical. The intermediate region R3 includes a plurality of (two in this embodiment) intermediate hard materials 113 . In this embodiment, the width W3 of the intermediate hard material 113 becomes smaller from the terminal region R1 side toward the central region R2 side. In this embodiment, the widthwise outer edge 113e of each intermediate hard material 113 is located widthwise outside the widthwise outer edge 112e of the central hard material 112 and widthwise inside the widthwise outer edge 111e of the terminal hard material 111 .

In the seismic isolation device 1B according to this embodiment, a plurality of intermediate hard materials 113 are arranged in the intermediate region R3, and the width W3 of the plurality of intermediate hard materials 113 extends from the terminal region R1 side to the central region R2 side. It is preferable that it becomes smaller toward . In the present embodiment, the width W3 of the plurality of intermediate hard materials 113 decreases from the terminal region R1 side toward the central region R2 side. In this case, the local stress concentration occurring in the end region R1 can be further suppressed, and the durability can be further improved.

In the base isolation device 1B according to this embodiment, a plurality of terminal hard materials 111 are arranged in the terminal region R1, and the width W1 of the plurality of terminal hard materials 111 is preferably the same. In this embodiment, the widths W1 of the plurality of terminal hard materials 111 are the same. In this case, since a plurality of terminal hard materials 111 are provided, local stress concentration occurring in the terminal region R1 can be further suppressed, and buckling resistance and durability can be further improved.

In the seismic isolation device 1B according to this embodiment, the widthwise outer edges of the terminal hard material 111 adjacent to the intermediate hard material 113, the two intermediate hard materials 113, and the central hard material 112 adjacent to the intermediate hard material 113 The imaginary ridgeline L formed by connecting 111e, 113e, and 112e shall have an acute angle A with respect to the vertical direction of 45° to 80° in a vertical cross-sectional view of the seismic isolation device 1B. can be done. If the angle A is less than 45°, the effect of suppressing buckling is small. If the angle A exceeds 80°, the effect of suppressing buckling is small, and local peeling tends to occur on the compression side of the widthwise outer edge 111e of the terminal hard material 111 . According to the present embodiment, the virtual ridge line L has an acute angle A with respect to the vertical direction of 45° to 80° in the vertical cross-sectional view of the seismic isolation device 1B. In this embodiment, the angle A is a numerical value in the range of 45° to 80°. Therefore, according to this embodiment, the effect of improving buckling is particularly high.

In particular, in the seismic isolation device 1B according to the present embodiment, the imaginary ridge line L is linear in the vertical cross-sectional view of the seismic isolation device 1B. In this case, buckling can be made more difficult to occur.

As described above, according to each embodiment of the present invention, a seismic isolation device excellent in buckling performance and durability can be provided without impairing the required seismic isolation performance.

In the present embodiment, the outer surface shape (contour shape) of the laminated structure 10 is a combination of linear shapes in a vertical cross-sectional view of the seismic isolation device. In this case, in a vertical cross-sectional view, the contour shape of the laminated structure 10 is a shape in which there is a large difference between the widthwise outer edge 111e of the terminal hard material 111 and the widthwise outer edge 112e of the central hard material 112, that is, as shown in FIG. , the shape is hollowed out toward the central axis O. Therefore, according to the present embodiment, the proportion of the soft material can be reduced as compared with the case where the outer surface has a curved shape, so that the seismic isolation performance can be improved. However, as another seismic isolation device according to the present invention, the width direction outer edge 111e of the terminal hard material 111 adjacent to the intermediate hard material 113 and the width direction outer edge of the intermediate hard material 113 in the vertical cross-sectional view of the seismic isolation device 113e and an imaginary ridge line connecting the widthwise outer edge 112e of the central hard material 112 adjacent to the intermediate hard material 113 has a curved convex shape toward the central axis O. That is, according to the present invention, in the vertical cross-sectional view of the seismic isolation device, the outer surface shape of the laminated structure 10 has a curved shape convex toward the central axis O, such as an arc-like cross-section or a similar arc-like shape. is also included.

The natural vibration period becomes shorter as the ratio of the soft material 12 increases. Therefore, it is preferable to suppress the proportion of the soft material 12 . According to the seismic isolation device according to the present invention, in a cross-sectional view of the seismic isolation device in the vertical direction, the contour shape of the laminated structure 10 is simply a curved shape that is convex toward the central axis O. The proportion occupied by the soft material 12 is reduced. Therefore, according to the seismic isolation device according to the present invention, it is possible to exhibit more seismic isolation performance than a seismic isolation device having a curved outer surface.

The foregoing merely discloses some embodiments of the present invention, and various modifications are possible within the scope of the claims. For example, according to the invention, the seismic isolation device may comprise a plug (core). Specifically, in each embodiment, a plug extending along the central axis O can penetrate through the central portion of the laminated structure 10 . The plug is preferably made of metal such as lead or tin. The various configurations employed in the respective embodiments described above can be replaced with each other as appropriate. For example, in the seismic isolation device 1B according to the second embodiment, the width W1 of the plurality of terminal hard materials 111 is the same, but the width W1 of the plurality of terminal hard materials 111 is different from that of the second embodiment. Similar to the intermediate hard material 113, it can be reduced from the terminal region R1 side toward the central region R2 side. That is, according to the reference example of the present invention, when a plurality of terminal hard materials 111 are arranged in the terminal region R1, the width W1 of the plurality of terminal hard materials 111 extends from the central region R2 side to the terminal region R1 side. It can also be made to increase as it goes to .

(analysis)
In order to confirm the effect of the seismic isolation device according to the present invention, FEM (Finite Element Method) analysis based on W2/W1 (hereinafter also referred to as "FEM analysis based on width ratio") and the angle A of the virtual ridgeline L Two types of analysis were performed: FEM analysis based on angle (hereinafter also referred to as "FEM analysis based on angle"). In the FEM analysis, buckling strain, breaking strain and natural vibration period were verified. Marc analysis software manufactured by MSC Software was used for the FEM analysis.

In the FEM analysis, an analysis model that reproduces the contour shape of the laminated structure 10 according to the first embodiment of the present invention was used. In the FEM analysis based on the width ratio, six analysis models were created. Also, in the FEM analysis based on the angle, five analysis models were created. The input load used in these FEM analyzes is 1300 kN.

The mesh of the hard material was a tetrahedron with a side of about 50 to 120 mm per layer, and 54 meshes. The meshes of the soft material were tetrahedrons with sides of 50 to 120 mm per layer, and the number of meshes was 54. [Table 1] below shows the parameters of the analysis model.

[Table 2] below shows the buckling performance, durability performance (breaking performance), and seismic isolation performance evaluated based on the results of the FEM analysis based on the width ratio. Here, the "buckling strain" is the strain (%) when buckling occurs in the analysis model, and the strain mainly occurs in the terminal region. In addition, "improved buckling strain" refers to the buckling strain of a conventional laminated structure (in this analysis, a laminated structure with a related performance of R = 1) that does not include the numerical range of the seismic isolation device according to the present invention. is the ratio of the buckling strain (%) of the analytical model to be analyzed when is set to 100. Therefore, in this evaluation, the larger the value of the improved buckling strain, the less buckling occurs and the better the buckling performance. Also, the "breaking strain" is the strain (%) when the soft material breaks, and the strain mainly occurs in the end region. Therefore, in this evaluation, the larger the value of the breaking strain, the more difficult it was to break, and the better the breaking performance. Note that "NA" is an unusable value. Also, the "100% equivalent period" T is obtained as follows. When a displacement (x)-load (y) graph of a laminated structure is drawn, it usually forms a loop. Here, when the position of the most + (plus) displacement x on the loop and the position of the most - (minus) displacement x are connected by a straight line, let the slope of this straight line be k. Then, it is obtained by T=2π√(m/k) (m is the mass of the laminated structure). Therefore, in this evaluation, the larger the value of the 100% equivalent period, the better the seismic isolation performance. In [Table 2], when the buckling strain is 400% or more, it is evaluated as ⊚ and good. In addition, when it is improved by 15% or more from the conventional structure, it is evaluated as ◯, which is generally good. In addition, x is an evaluation that there is room for improvement other than the above.

Referring to Table 2, in the analysis model with W2/W1 = 0.55, there is room for improvement in the evaluation of durability performance and seismic isolation performance. Performance and seismic isolation performance were found to be good. In addition, in the analysis model with W2/W1 = 0.98 or more, there is room for improvement in the evaluation of buckling performance, while in the analysis model with W2/W1 ≤ 0.97, the buckling performance is good. One thing was recognized. Therefore, from these evaluation results, if the analysis model is in the range of 0.6≦W2/W1≦0.97, all of buckling performance, durability performance (breaking performance) and seismic isolation performance are good. One thing is clear.

[Table 3] below shows the buckling performance evaluated based on the results of the FEM analysis based on the angle. Here, "buckling strain" and "improved buckling strain" are the same as in [Table 2]. The term "end tensile strain" refers to the strain applied to the soft material in contact with the end of the hard material on the outermost side (opposite to the center). The smaller this value, the better. Furthermore, in [Table 3], the evaluations indicated by ⊚, ◯ and × are also the same as in [Table 2].

Referring to Table 3, in the analysis model in which the angle A of the imaginary ridge line L is 40° or less and the analysis model in which the angle A is 85°, there is room for improvement in the evaluation of the buckling performance and the curling performance. It was confirmed that the analytical model in which the angle A of the imaginary ridge line L was 45° to 80° had good buckling performance and rolling-up performance. Therefore, from these evaluation results, it is clear that an analysis model in which the angle A of the imaginary ridgeline L is in the range of 40° to 85° has good buckling performance.

1A: seismic isolation device (first embodiment), 1B: seismic isolation device (second embodiment), 10: laminated structure, 11: hard material, 111: end hard material, 112: central hard material, 113 : Intermediate hard material 111e: Width direction outer edge of terminal hard material 112e: Width direction outer edge of central hard material 113e: Width direction outer edge of intermediate hard material 12: Soft material A: Angle H0: Laminated structure Vertical height H3: Vertical height of intermediate region L: Virtual ridgeline ΔL1: Difference between widthwise outer edge of terminal hard material and widthwise outer edge of intermediate hard material ΔL2: Intermediate hard material Difference between the widthwise outer edge and the widthwise outer edge of the central rigid material, R1: terminal region, R2: central region, R3: intermediate region, W1: width between the transversely outer edges of the terminal rigid material, W2: central rigid Width between widthwise outer edges of material

Claims (7)

A seismic isolation device comprising a laminated structure in which hard materials and soft materials are alternately arranged in the vertical direction,
The laminated structure comprises two end regions located respectively on the upper side and the lower side, a central region located between the two end regions, and the central region between the central region and the end regions. and two intermediate regions located adjacent to said terminal regions,
the rigid material disposed in the terminal region is at least one terminal rigid material;
the hard material disposed in the central region is at least one central hard material;
the hard material disposed in the intermediate region is at least one intermediate hard material;
The widthwise outer edges of the terminal hard materials are located on the widthwise outer side of the widthwise outer edges of the central hard material, and the widthwise outer edges of the intermediate hard materials are positioned further than the widthwise outer edges of the central hard material. is located on the widthwise outer side and on the widthwise inner side of the widthwise outer edge of the terminal hard material, and
The ratio (W2/W1) of the width W2 between the widthwise outer edges of the central hard material to the width W1 between the widthwise outer edges of the terminal hard materials is
0.6≦(W2/W1)≦0.97 ,
A seismic isolation device, wherein a plurality of terminal hard materials are arranged in the terminal region, and the widths of the plurality of terminal hard materials are the same. 2. The immunity according to claim 1, wherein a plurality of said intermediate hard materials are arranged in said intermediate region, and widths of said plurality of intermediate hard materials decrease from said terminal region side toward said central region side. seismic device. The seismic isolation device according to claim 1 or 2, wherein a plurality of said central hard materials are arranged in said central region, and widths of said plurality of central hard materials are the same. Width direction outer edges of the terminal hard material adjacent to the intermediate hard material, the intermediate hard material, and the central hard material adjacent to the intermediate hard material in a vertical cross-sectional view of the seismic isolation device The seismic isolation device according to any one of claims 1 to 3 , wherein the acute angle A formed by the imaginary ridgeline with respect to the vertical direction is 45° to 80° . 5. The seismic isolation device according to claim 4 , wherein said imaginary ridgeline is linear in a vertical cross-sectional view of said seismic isolation device. 6. The ratio (H3/H0) of the vertical height H3 of the intermediate region to the vertical height H0 of the laminated structure is 0.01 to 0.1 . The seismic isolation device described in . The seismic isolation device according to any one of claims 1 to 6 , wherein the outer surface shape of said laminated structure is a combination of linear shapes in a vertical cross-sectional view of the seismic isolation device.

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