Seismic isolation stopper and seismic isolation structure

Abstract

To provide a seismic base isolation stopper that saves space and is easy to install and replace, and a seismic base isolation structure equipped with the seismic base isolation stopper.SOLUTION: A seismic base isolation stopper 1 according to the present invention, which prevents excessive deformation of seismic base isolation devices provided in a seismic base isolation layer 2 of a building, has a first steel bar 5 installed so as to extend downward from the structure above the seismic base isolation layer 2, a second steel bar 7 installed so as to extend upward from the structure below the seismic base isolation layer 2, a first steel plate 9 whose one end is rotatably attached to the lower end of the first steel bar 5, a second steel plate 11 whose one end is rotatably attached to the upper end of the second steel bar 7 and a connecting mechanism 13 rotatably connecting the other end of the first steel plate 9 and the other end of the second steel plate 11.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a seismic stopper for preventing excessive deformation of a seismic isolation device provided in a seismic isolation layer of a building and a seismic isolation structure including the seismic stopper.

Background Art

[0002] In recent years, due to concerns about increasingly severe earthquake damage, the spread of seismic isolation structures has been progressing, mainly in super high-rise buildings. A seismic isolation structure is a structure that significantly reduces the sway of a building during an earthquake by providing a seismic isolation layer at a predetermined floor of the building.

[0003] The seismic isolation device provided in the seismic isolation layer mainly includes an isolator (bearing) with a small horizontal rigidity relative to the vertical rigidity and a damper that absorbs seismic energy input to the building.

[0004] On the other hand, with the increase in the magnitude of recent earthquakes, it has been pointed out that there is a possibility that the building and the surrounding retaining walls will collide due to displacements of the seismic isolation layer exceeding the assumptions during an earthquake, and research to prevent this has been underway.

[0005] As a technology for this, a seismic stopper has been devised as a device for preventing excessive deformation of the seismic isolation layer when an earthquake exceeding the assumptions occurs. The seismic stopper is a mechanism that operates when a predetermined deformation occurs in the seismic isolation layer to generate a reaction force and suppress the displacement of the seismic isolation layer.

[0006] Patent Document 1 is a mechanism that generates a reaction force when a predetermined deformation occurs by providing a tensile load transmission member and an interference portion between the peripheral structure and the seismic isolation structure.

[0007] Patent Document 2 is a seismic stopper using steel materials, which is a mechanism combining a steel bar and a circular steel pipe covering it. When a predetermined displacement of the seismic isolation layer occurs, the steel bar and the steel pipe come into contact to generate a reaction force.

[0008] In addition, Patent Document 3 discloses a seismic isolation device that is not a seismic isolation stopper but is for protecting precision instruments and other structures, i.e., the supported body, from shaking during an earthquake and ensuring safety for humans. The seismic isolation device of Patent Document 3 "comprises a base installed on the floor surface, a first link portion rotatably provided on a first support portion of the base and having a first arm, a second link portion rotatably provided on a second support portion provided at the tip of the first arm and having a second arm, and a support plate rotatably provided on a third support portion provided at the tip of the second arm and supporting the supported body" (see paragraph 0005).

Prior Art Documents

Patent Documents

[0009]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0010] While the mechanism of Patent Document 1 is a simple mechanism, since the mechanisms for resisting compression and tension are separate, it is necessary to create a tension load transmission member and an interference portion respectively, which makes the construction troublesome. In addition, the device of Patent Document 2 has a simple mechanism, but on the other hand, the installation of the steel pipe is troublesome, and since it is necessary to provide clearances in all directions between the steel bar and the steel pipe, there is a problem that a large installation space is required.

[0011] In addition to Patent Documents 1 and 2, numerous shapes and mechanisms have been proposed as seismic isolation stoppers, but there are problems such as the need for labor in manufacturing the seismic isolation stopper and the peripheral structure, the need for a large space for installation, and the difficulty in replacing the damaged seismic isolation stopper after an earthquake.

[0012] Note that the device in Patent Document 3 is not a seismic isolation stopper provided in the seismic isolation layer in the first place. Instead, it supports a supported body such as precision machinery with a support plate so as not to transmit the shaking of an earthquake to the supported body, and its place of use and purpose of use are completely different from those of the present invention.

[0013] The present invention has been made to solve such problems, and an object thereof is to provide a seismic isolation stopper that can be installed and replaced easily with less space, and a seismic isolation structure including the seismic isolation stopper.

Means for Solving the Problems

[0014] (1) The seismic isolation stopper according to the present invention prevents excessive deformation of a seismic isolation device provided in a seismic isolation layer of a building, and a first steel bar installed so as to extend downward from a structure above the seismic isolation layer, a second steel bar installed so as to extend upward from a structure below the seismic isolation layer, a first steel plate having one end rotatably attached to the lower end of the first steel bar, a second steel plate having one end rotatably attached to the upper end of the second steel bar, and a connecting mechanism that rotatably connects the other end of the first steel plate and the other end of the second steel plate.

[0015] (2) Further, in the above (1), the connecting mechanism is characterized in that it is constituted by a steel bar rotatably disposed between the other end of the first steel plate and the other end of the second steel plate.

[0016] (3) Further, in the above (1), the connecting mechanism includes a first connecting steel bar having one end rotatably attached to the other end of the first steel plate, a second connecting steel bar having one end rotatably attached to the other end of the second steel plate, and a connecting steel plate that rotatably connects the other end of the first connecting steel bar and the other end of the second connecting steel bar.

[0017] (4) Also, a seismic isolation stopper for preventing excessive deformation of a seismic isolation device provided in a seismic isolation layer of a building, a first steel bar installed so as to extend downward from a structure above the seismic isolation layer, a second steel bar installed so as to extend upward from a structure below the seismic isolation layer, and a steel plate disposed between a lower end portion of the first steel bar and an upper end portion of the second steel bar, wherein the steel plate has a long hole into which the lower end portion of the first steel bar and the upper end portion of the second steel bar are inserted and which allows relative movement of separation and contact.

[0018] (5) The seismic isolation structure according to the present invention includes the seismic isolation stopper according to any one of (1) to (4) above and a seismic isolation device provided in the seismic isolation layer.

Effect of the Invention

[0019] The seismic isolation stopper of the present invention includes a first steel bar installed so as to extend downward from a structure above the seismic isolation layer, a second steel bar installed so as to extend upward from a structure below the seismic isolation layer, a first steel plate having one end rotatably attached to the lower end portion of the first steel bar, a second steel plate having one end rotatably attached to the upper end portion of the second steel bar, and a connecting mechanism for rotatably connecting the other end portion of the first steel plate and the other end portion of the second steel plate. Therefore, it saves space and is easy to install and replace.

Brief Description of the Drawings

[0020]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Figure 18

Modes for Carrying Out the Invention

[0021] [Embodiment 1] The configuration of the seismic isolation stopper 1 according to this embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 shows a state in which the superstructure 3a (hereinafter, "upper structure 3a") above the seismic isolation layer 2 and the substructure 3b (hereinafter, "lower structure 3b") below the seismic isolation layer 2 are not horizontally displaced, and FIG. 2 shows a state in which the upper structure 3a and the lower structure 3b are horizontally displaced until immediately before the seismic isolation stopper 1 functions as a stopper.

[0022] The seismic isolation stopper 1 according to this embodiment is for preventing excessive deformation of a seismic isolation device (not shown) provided in the seismic isolation layer 2 of a building. As shown in FIGS. 1 and 2, it includes a first steel bar 5 installed so as to extend downward from the upper structure 3a, and a second steel bar 7 installed so as to extend upward from the lower structure 3b. Further, it includes a first steel plate 9 whose one end is rotatably attached to the lower end of the first steel bar 5, a second steel plate 11 whose one end is rotatably attached to the upper end of the second steel plate 11, and a connecting mechanism 13 that rotatably connects the other end of the first steel plate 9 and the other end of the second steel plate 11. Hereinafter, each configuration will be described in detail.

[0023] <Seismic isolation layer> A seismic isolation device (not shown) is provided in the seismic isolation layer 2. Examples of the seismic isolation device include those composed of an isolator (bearing) and a damper, and examples of the bearing include a laminated rubber bearing, a sliding bearing, a rolling bearing, etc. The seismic isolation layer 2 serves to separate (insulate) the ground and the structure in a building, and a seismic isolation device for absorbing energy is provided here. The seismic isolation device supports the load of the structure, but the seismic isolation stopper 1 does not support the load of the structure.

[0024] <First steel bar> The first steel bar 5 is installed so as to extend downward from the upper structure 3a. As shown in FIGS. 1 and 2, the proximal end side of the first steel bar 5 is embedded and fixed in the upper structure 3a. However, the fixing method of the first steel bar 5 is not limited to this, and a threaded portion may be provided on the proximal end side and screwed into a threaded hole provided in a steel plate 15 (see FIG. 3) fixed to the upper structure 3a for fixing. It is preferable to provide a nut for preventing loosening at the fixing portion. Thus, if the proximal end side of the first steel bar 5 is fixed by screwing, it can be easily replaced, which is preferable.

[0025] The position of the lower end of the first steel bar 5 is slightly higher than the middle in the height direction of the seismic isolation layer 2. And a first steel plate 9 is rotatably attached to the lower end portion of the first steel bar 5. The attachment method of the first steel plate 9 is to provide a hole in the first steel plate 9 through which the first steel bar 5 can be inserted, and with the lower end portion of the first steel bar 5 inserted into the hole, the up and down movement of the first steel plate 9 is restricted by nuts 17. Thus, the first steel plate 9 is attached to the lower end portion of the first steel bar 5 in a state where it can rotate and the axial movement of the first steel bar 5 is restricted.

[0026] <Second steel bar> The second steel bar 7 is installed so as to extend upward from the lower structure 3b. The attachment method of the second steel bar 7 to the structure is the same as the attachment method of the first steel bar 5 described above. The position of the upper end of the second steel bar 7 is slightly lower than the middle in the height direction of the seismic isolation layer 2. And a second steel plate 11 is rotatably attached to the upper end portion of the second steel bar 7. The attachment method of the second steel plate 11 is the same as the attachment method of the first steel plate 9 to the first steel bar 5 described above.

[0027] <First steel plate> One end of the first steel plate 9 is rotatably attached to the lower end portion of the first steel bar 5. The attachment method of the first steel plate 9 to the first steel bar 5 is as described above. The shape, thickness, etc. of the first steel plate 9 may be appropriately set based on the specifications of the seismic isolation device installed in the seismic isolation layer 2 so as to have a strength that exhibits the function as a seismic isolation stopper.

[0028] <Second steel plate> One end of the second steel plate 11 is rotatably attached to the upper end of the second steel plate 11. The method of attaching the second steel plate 11 to the second steel bar 7 is the same as the method of attaching the first steel plate 9 to the first steel bar 5 described above. The shape, thickness, etc. of the second steel plate 11 are preferably the same as those of the first steel plate 9.

[0029] <Connecting mechanism> The connecting mechanism 13 rotatably connects the other end of the first steel plate 9 and the other end of the second steel plate 11. As shown in FIGS. 1 and 2, the connecting mechanism 13 of the present embodiment is constituted by a connecting steel bar 19 rotatably disposed between the other end of the first steel plate 9 and the other end of the second steel plate 11. More specifically, nuts 17 for preventing disengagement and washers (not shown) are provided on the upper end side and the lower end side of the connecting steel bar 19.

[0030] The operation of the seismic isolation stopper 1 of the present embodiment configured as described above will be described with reference to FIGS. 3 to 5. When the upper and lower structures 3a and 3b of the seismic isolation layer 2 are horizontally displaced due to an earthquake from the state shown in FIG. 3 before the earthquake, as shown in FIG. 4, the first steel plate 9 and the second steel plate 11 rotate, and the first steel bar 5 and the second steel bar 7 move horizontally without being restricted and do not function as stoppers. During this period, a seismic isolation effect is exerted by a seismic isolation device (not shown). When the horizontal displacement of the upper structure 3a and the lower structure 3b occurs beyond the state where the first steel plate 9 and the second steel plate 11 are in a straight line (see FIG. 2), as shown in FIG. 5, a load acts on the first steel bar 5, the second steel bar 7, the first steel plate 9, and the second steel plate 11, and functions to suppress the horizontal displacement.

[0031] Here, let the sum of the clearances between the first steel bar 5, the second steel bar 7, and the connecting steel bar 19 and the holes into which they are inserted be Δb, and let the length obtained by subtracting the horizontal distance between the first steel bar 5 and the second steel bar 7 from the total length of the intervals of the bolt holes provided in the first steel plate 9 and the second steel plate 11 be Δh. During an earthquake, when the displacement of the seismic isolation layer 2 is less than or equal to Δb + Δh, the steel plates rotate or the first steel bar 5, the second steel bar 7, and the connecting steel bar 19 move within the clearance between the steel plates and the holes. However, when the displacement of the seismic isolation layer 2 exceeds Δb + Δh, only the deformation of the first steel bar 5, the second steel bar 7, the first steel plate 9, and the second steel plate 11 progresses to prevent excessive displacement of the seismic isolation layer 2. The holes provided in the first steel plate 9 and the second steel plate 11 are made larger than ordinary bolt holes, so that the horizontal movement amount until the seismic isolation stopper 1 acts can be adjusted.

[0032] In addition, when the superstructure 3a moves to the left side in the figure from the state shown in FIG. 5 to the state shown in FIG. 4, and further moves to the left side in the figure to the state shown in FIG. 3, and moves to the left side in the figure beyond the state shown in FIG. 3, it can move to the state shown in FIG. 6.

[0033] When a large displacement occurs in the seismic isolation layer, the deflection of the first steel bar 5 and the second steel bar 7 increases, thereby exerting a restoring force to return the seismic isolation layer to its original position.

[0034] The seismic isolation stopper 1 according to the present embodiment configured as described above is mainly composed of only steel bars and steel plates, so it is easy to manufacture. In addition, since the seismic isolation stopper 1 can be disassembled into each part, it can be easily replaced even when the seismic isolation stopper 1 is damaged after an earthquake.

[0035] The strength of the steel materials of the first steel bar 5, the second steel bar 7, the first steel plate 9, and the second steel plate 11 may be set according to the usage range required at the time of design. By increasing the strength, the elastic range of the seismic isolation stopper 1 can be increased, and damage to the seismic isolation stopper 1 during an earthquake can be reduced. It is desirable that the strength of the nut 17 and the washer is equal to or greater than the strength of the steel bar to which the nut 17 and the washer are attached. Note that the tightening torque of the nut 17 when installing the seismic isolation stopper 1 absorbs energy due to friction during deformation as it increases, and functions as a stopper together with the first steel bar 5, the second steel bar 7, the first steel plate 9, and the second steel plate 11. The nut 17 is provided with a locknut as needed.

[0036] The above-described connecting mechanism 13 was constituted by a connecting steel bar 19 rotatably disposed between the other end of the first steel plate 9 and the other end of the second steel plate 11. However, the connecting mechanism 13 of the present invention is not limited to this. As shown in FIGS. 7 and 8, as a main configuration, it may be constituted by a link composed of a combination of two steel bars, a first connecting steel bar 19a and a second connecting steel bar 19b, and one connecting steel plate 21. That is, it includes a first connecting steel bar 19a having one end rotatably attached to the other end of the first steel plate 9, and a second connecting steel bar 19b having one end rotatably attached to the other end of the second steel plate 11. And it is configured to include a connecting steel plate 21 that rotatably connects the other end of the first connecting steel bar 19a and the other end of the second connecting steel bar 19b.

[0037] By configuring the connecting mechanism 13 as described above, it can be folded smaller than the one constituted only by the connecting steel bar 19 shown in FIGS. 1 and 2, and the space required for installation can be reduced (see FIG. 7). Note that, the more the number of connecting steel plates 21 constituting the connecting mechanism 13, the smaller the size of the seismic isolation stopper 1 at the time of installation can be made. In that sense, the number of connecting steel plates 21 is not limited to one, but when the number of connecting steel plates 21 increases, the number of parts of the seismic isolation stopper 1 increases and the assembly work becomes larger, so one is preferable.

[0038] Further, the first steel plate 9, the second steel plate 11, and the connecting steel plate 21 are not limited to rectangular shapes as shown in FIGS. 1, 7, and 8, and may be arc-shaped, for example, a U-shaped steel plate 23 as shown in FIG. 9. By making the connecting steel plate 21 arc-shaped, the elastic range of the seismic isolation stopper 1 can be increased, and damage to the seismic isolation stopper 1 during an earthquake can be reduced.

[0039] Note that, for some nuts 17, for example, as shown in Fig. 10, the nut 17 provided between the first steel plate 9 and the connecting rod steel 19 does not introduce torque, but provides a predetermined space S between the nut 17 and the first steel plate 9, so that it is not affected by the up and down movement during an earthquake and can show stable mechanical behavior, which is preferable.

[0040] In the above description, the seismic isolation stopper 1 was installed at a location different from the seismic isolation devices such as isolators and dampers within the seismic isolation layer 2. However, as shown in Fig. 11, it is also possible to install it at the same location as the seismic isolation device 25.

[0041] [Embodiment 2] The seismic isolation stopper 26 of this embodiment has a first steel bar 5 installed so as to extend downward from the superstructure 3a and a second steel bar 7 installed so as to extend upward from the substructure 3b, as shown in Figs. 12 and 13. In addition, between the lower end of the first steel bar 5 and the upper end of the second steel bar 7, there is a long hole steel plate 29 provided with a long hole 27.

[0042] Regarding the seismic isolation layer 2, the superstructure 3a, the substructure 3b, the first steel bar 5, and the second steel bar 7, they are the same as those in Embodiment 1, so the description is omitted and the long hole steel plate 29 will be described. The long hole steel plate 29 has a long hole 27 into which the lower end of the first steel bar 5 and the upper end of the second steel bar 7 are inserted and can move relative to each other by separating and contacting. The lower end of the first steel bar 5 is inserted into the long hole 27, as shown in Figs. 12 and 13. And, for anti - pull - out, a pair of nuts 17 are provided so as to sandwich the long hole steel plate 29. The upper end of the second steel plate 11 is rotatably connected to a hole different from the long hole 27 provided in the long hole steel plate 29.

[0043] In the seismic isolation stopper 26 of this embodiment configured as described above, in the installed state before an earthquake, as shown in Fig. 12, the horizontal distance between the first steel bar 5 and the second steel bar 7 is in a close state. In this state, when an earthquake occurs and the superstructure 3a and the substructure 3b undergo horizontal displacement, as shown in Fig. 13, the lower end of the first steel bar 5 moves within the long hole 27, and the first steel bar 5 and the second steel bar 7 are not restricted and do not function as stoppers. During this period, the seismic isolation effect is exerted by a seismic isolation device (not shown). When the horizontal displacement of the superstructure 3a and the substructure 3b occurs beyond the state where the lower end of the first steel bar 5 has moved to the end of the long hole 27 (see Fig. 13), a load acts on the first steel bar 5, the second steel bar 7, and the long hole steel plate 29, and it functions to suppress the horizontal displacement.

[0044] When the superstructure 3a moves to the left side in the figure from the state shown in Fig. 2 to the state shown in Fig. 12 and further moves to the left side in the figure, the long hole steel plate 29 can rotate around the second steel bar 7 and move to the state shown in Fig. 14.

[0045] The seismic isolation structure is constituted by the seismic isolation stoppers 1 and 26 of Embodiments 1 and 2 and the seismic isolation device provided in the seismic isolation layer 2.

Example

[0046] As examples, specific design examples 1 and 2 are shown. <Design Example 1> As Design Example 1, assume that the height of the seismic isolation layer 2 where the seismic isolation stopper 1 is installed is 500 mm, and consider the case where the seismic isolation stopper 1 starts to act after the displacement of the seismic isolation layer 2 reaches 400 mm. The form of the seismic isolation stopper 1 is mainly composed of the first steel bar 5, the second steel bar 7, the first steel plate 9, the second steel plate 11, and the connecting steel bar 19 shown in Fig. 1.

[0047] The first steel bar 5, the second steel bar 7, and the connecting steel bar 19 are made of ABR400 anchor bolts M48 of JIS B 1220. The first steel bar 5, the second steel bar 7, the connecting steel bar 19, the first steel plate 9, and the second steel plate 11 are made of steel with a tensile strength of 400 N / mm 2 grade. The nut 17 and washer are made of steel materials with a strength of the first bar steel 5, the second bar steel 7, and the connecting bar steel 19 or more. The first steel plate 9 and the second steel plate 11 have a plate thickness of 32 mm and a width of 100 mm in order to ensure rigidity and endurance. The first steel plate 9 and the second steel plate 11 are provided with holes having a diameter of 50 mm, and the intervals between the holes provided in the first steel plate 9 and the second steel plate 11 are both 198 mm. In order to ensure the influence of vertical movement during an earthquake and the clearance during stopper deformation, a space S of about 50 mm is provided between the nuts 17 provided between the first steel plate 9 and the connecting bar steel 19, and a shock absorber is attached, as shown in FIG. 10.

[0048] According to the above Design Example 1, the total clearance Δb between the first bar steel 5, the second bar steel 7, the connecting bar steel 19, and the holes into which they are inserted is (50 - 48) / 2×4 = 4 mm. Also, the length obtained by subtracting the horizontal distance between the first bar steel 5 and the second bar steel 7 from the total length of the intervals between the bolt holes provided in the first steel plate 9 and the second steel plate 11 is Δh = 198×2 mm. Therefore, the seismic isolation stopper 1 starts to act after the displacement amount of the seismic isolation layer 2 reaches Δb + Δh = 400 mm.

[0049] <Design Example 2> As Design Example 2, assume a case where the height of the seismic isolation layer 2 where the seismic isolation stopper 1 is installed is 400 mm, and consider a case where the seismic isolation stopper 1 starts to act after the displacement of the seismic isolation layer 2 reaches 300 mm. The bar steel is an ABR400 anchor bolt M48 of JIS B 1220. The form of the seismic isolation stopper 1 is the same as that shown in FIG. 1 in Design Example 1, and the main components are the first bar steel 5, the second bar steel 7, the connecting bar steel 19, the first steel plate 9, and the second steel plate 11.

[0050] In this design example, the height of the seismic isolation layer 2 is smaller compared to Design Example 1. In this case, in order to ensure the elastic deformation amount of the seismic isolation stopper 1 when the first bar steel 5 and the second bar steel 7 become shorter, the tensile strength is 490 N / mm, which is higher than that of Design Example 1. 2Grade steel is used for the first steel bar 5, the second steel bar 7, the connecting steel bar 19, the first steel plate 9 and the second steel plate 11. The first steel plate 9 and the second steel plate 11 shall have a plate thickness of 32 mm and a width of 100 mm to ensure rigidity and bearing capacity. The nut 17 and the washer are made of steel with a strength higher than that of the steel bar. The first steel plate 9 and the second steel plate 11 are provided with oversize holes with a diameter of 60 mm, and the spacing between the holes to be processed is 138 mm for both. Similar to Design Example 1, in order to ensure the influence of vertical movement during an earthquake and the clearance during the deformation of the stopper, a space S of about 50 mm is provided between the nuts 17 provided between the first steel plate 9 and the connecting steel bar 19, and a shock absorber is installed.

[0051] According to the above Design Example 2, Δb = (60 - 48) / 2 × 4 = 24, Δh = 138 × 2, Δb + Δh = 300 mm. The seismic isolation stopper 1 starts to act after the displacement of the seismic isolation layer 2 reaches 300 mm.

Explanation of Symbols

[0052] 1 Seismic isolation stopper (Embodiment 1) 2 Seismic isolation layer 3a Superstructure 3b Substructure 5 First steel bar 7 Second steel bar 9 First steel plate 11 Second steel plate 13 Connecting mechanism 15 Steel plate 17 Nut 19 Connecting steel bar 19a First connecting steel bar 19b Second connecting steel bar 21 Connecting steel plate 23 U-shaped steel plate 25 Seismic isolation device 26 Seismic isolation stopper (Embodiment 2) 27 Long hole 29 Long hole steel plate

Claims

1. A seismic stopper for preventing excessive deformation of a seismic isolation device provided in a seismic isolation layer of a building, comprising: a first steel bar installed to extend downward from a structure above the seismic isolation layer; a second steel bar installed to extend upward from a structure below the seismic isolation layer; a first steel plate having one end rotatably attached to the lower end of the first steel bar about the first steel bar as a rotation axis; a second steel plate having one end rotatably attached to the upper end of the second steel bar about the second steel bar as a rotation axis; and a connecting mechanism for rotatably connecting the other end of the first steel plate and the other end of the second steel plate; wherein the first steel plate and the second steel plate are U-shaped steel plates, and are attached such that their plate surfaces face vertically; the connecting mechanism is constituted by a connecting steel bar disposed between the other end of the first steel plate and the other end of the second steel plate, and the first steel plate and the second steel plate are rotatable about the connecting steel bar as a rotation axis; when the displacement amount of the seismic isolation layer exceeds a predetermined amount, deformation of the first steel bar, the second steel bar, the first steel plate, and the second steel plate progresses to prevent excessive displacement of the seismic isolation layer. The seismic stopper is characterized by this.

2. A seismic stopper for preventing excessive deformation of a seismic isolation device provided in a seismic isolation layer of a building, comprising: a first steel bar installed to extend downward from a structure above the seismic isolation layer; a second steel bar installed to extend upward from a structure below the seismic isolation layer; a first steel plate having one end rotatably attached to the lower end of the first steel bar about the first steel bar as a rotation axis; a second steel plate having one end rotatably attached to the upper end of the second steel bar about the second steel bar as a rotation axis; and a connecting mechanism for rotatably connecting the other end of the first steel plate and the other end of the second steel plate; wherein the first steel plate and the second steel plate are U-shaped steel plates, and are attached such that their plate surfaces face vertically; The connecting mechanism includes a first connecting steel bar with one end rotatably attached to the other end of the first steel plate, a second connecting steel bar with one end rotatably attached to the other end of the second steel plate, and a connecting steel plate connecting the other end of the first connecting steel bar and the other end of the second connecting steel bar. The first steel plate is rotatable about an axis with the first connecting steel bar as the rotation axis, the second steel plate is rotatable about an axis with the second connecting steel bar as the rotation axis, and the connecting steel plate is rotatable about an axis with the first connecting steel bar and the second connecting steel bar as the rotation axes. The connecting steel plate is a U-shaped U-steel plate, and is attached so that the plate surface faces up and down. When the displacement amount of the seismic isolation layer exceeds a predetermined amount, the first steel bar, the second steel bar, the first steel plate, and the second steel plate are deformed to prevent excessive displacement of the seismic isolation layer. A seismic isolation stopper characterized by this.

3. A seismic isolation structure characterized by including the seismic isolation stopper according to claim 1 or 2 and a seismic isolation device provided in the seismic isolation layer.

Images