Multi-layered sagging seismic isolation structure

Abstract

In the case of small-scale pressurized floating seismic isolation structures, resonance occurs over a wide area at low vibration levels, and the challenge lies in how to suppress this resonance. [Solution] Two pressurized floating slack seismic isolation structures are stacked vertically one above the other, forming a two-layered, multi-layered slack seismic isolation structure with the upper layer as the upper seismic isolation layer and the lower layer as the lower seismic isolation layer. The layer where the lower extension piece of the upper seismic isolation layer and the upper extension piece of the lower seismic isolation layer of the multi-layered slack seismic isolation structure meet is designated as the intermediate layer. A horizontal force is applied by an excitation device directly below the center of gravity of this intermediate layer in the opposite direction to the direction in which the support resonates in the low vibration range, thereby damping low vibrations from the support.

Description

Technical Field

[0001] The present invention relates to a multi-layer non-sagging seismic isolation structure that suppresses resonance in a wide range with low vibration.

Background Art

[0002] A pressurized floating type non-sagging seismic isolation structure in which sealing materials surrounding a seismic isolation layer for confining a fluid are installed with longitudinal and lateral slack has been proposed. (See Patent Document 1) On the other hand, an invention related to a tuned mass damper type vibration control device, which is a passive vibration control device that suppresses the excitation of a house including a multi-story building due to ground vibration, has been proposed. (See Patent Document 2)

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] The pressurized floating type non-sagging seismic isolation structure 1 (hereinafter referred to as the basic structure) aims at absolute seismic isolation due to the effect of installing the sealing materials with longitudinal and lateral slack. However, in the basic structure installed on the ground or a pedestal, when the ground or the pedestal vibrates in the low vibration range, resonance occurs in the floating structure body 2. The problem to be solved by the invention is to suppress and damp the resonance in this low vibration range.

Means for Solving the Problems

[0005] The present invention provides a multi-layered slack seismic isolation structure 11 (hereinafter referred to as "the structure"), which is a seismic isolation structure that supports the floating structure body 2, which is the object to be seismically isolated, and comprises an upper seismic isolation layer (upper layer) 13 and a lower seismic isolation layer (lower layer) 12 that are stacked one above the other, each forming a pressurized floating body using a slackened sealing material 5, and an intermediate layer (intermediate member) 14 interposed between the sealing material 5 of the upper layer 13 and the sealing material 5 of the lower layer 12, which is supported by a support 6 for buoyancy, and is characterized by comprising a sliding sphere 17 as a fulcrum in the transmission of force from the support 6 to the intermediate member 14, and a transmission member 18 provided on the sliding sphere 17 that forms the point of force application and the point of application in the transmission of force from the support 6 to the intermediate member 14.

[0006] In this structure, the lower layer 12 includes a lower support member 15 as an intermediate member 14 that is buoyantly supported by a support 6, and the upper layer 13 includes an upper support member 16 that is buoyantly supported by the intermediate member 14 and supports the object 2. The support 6 and the lower support member 15 each have lower extension pieces 9 and 10 that extend horizontally and face each other in the vertical direction, the intermediate member 14 and the upper support member 16 each have upper extension pieces 9 and 10 that extend horizontally and face each other in the vertical direction, the sealing material 5 of the lower layer 12 is interposed between the lower extension pieces 9 and 10, and the sealing material 5 of the upper layer 13 is interposed between the upper extension pieces 9 and 10.

[0007] This structure is characterized by having an excitation device 19 that applies a horizontal force from the support 6 to the intermediate member 14, and the transmission member 18 being able to tilt in any direction with respect to the horizontal plane with the sliding sphere 17 as the fulcrum, and being in contact directly below the center of gravity of the intermediate member 14.

[0008] In this structure, the vibration device 19 is characterized by including an actuator 20 that orients the rotating table 21 in a direction that enables vibration control, and an actuator 20 that applies a horizontal force to the intermediate member 14.

[0009] In this structure, the vibration exciter 19 is suspended from the transmission member 18 and includes a weight 32 configured to be synchronized with the natural vibration of the structure.

[0010] In this structure, a first layer 35 is provided as the lower layer 12, a second layer 36 as the upper layer 13, and a third layer 37 is provided as the upper layer 13 when the second layer 36 is the lower layer 12, and is stacked on top of the first and second layers 35 and 36, with a first intermediate member 38 interposed between the sealant 5 of the first layer 35 and the sealant 5 of the second layer 36, and a first intermediate member 38 interposed between the sealant 5 of the second layer 36 and the sealant 5 of the third layer 37, A second intermediate member 39 is interposed between a first intermediate member 38, which acts as a support, and a second intermediate member 39 is interposed between them. Of the first intermediate member 38 and the second intermediate member 39, at least the first intermediate member 38 is equipped with a vibration device 19 similar to that provided for the intermediate member 14, a sliding sphere 17 as a fulcrum in the transmission of force from the support to the intermediate member, and a transmission member 18 provided on the sliding sphere 17 that forms the point of force application and the point of load application in the transmission of force from the support to the intermediate member. [Effects of the Invention]

[0011] According to the present invention, by connecting the transmission member 18 and the vibration exciter 19 so that a horizontal force acting in the opposite direction to the direction of vibration from the support 6 is applied directly below the center of gravity 33 of the intermediate member of the two-layer structure, resonance in the low vibration range can be suppressed and seismic damping performance can be improved. Furthermore, vibrations exceeding the low-vibration range are transmitted from the ground or platform through the members to the intermediate member 14, but are blocked from the upper layers to the floating structure body 2 by the seismic isolation function of the basic structure.

[0012] According to the present invention, by connecting the transmission member 18 and the vibration exciter 19 to a position 33 directly below the center of gravity of the intermediate members in the first and second stages of the three-layer structure, a horizontal force acting in the opposite direction to the direction of vibration from the support 6 and the second stage intermediate member 39 can be applied, thereby suppressing resonance in the low vibration range and improving seismic damping performance. Vibrations exceeding the low-frequency range are blocked by the uppermost third layer 37, similar to the two-layer system.

[0013] Although the present invention can be created for a structure with four or more layers in the same manner as the three-layer structure, the cost accumulates by approximately the same amount for each layer, and there is a problem in terms of cost-effectiveness because the seismic isolation effect obtained is not very different from that of the three-layer structure.

Brief Description of the Drawings

[0014] [Figure 1] It is an explanatory diagram showing an overview of the basic structure in which the buoyancy support is installed inside the seismic isolation layer 3. [Figure 2] It is an explanatory diagram showing an overview of the basic structure in which the buoyancy support is installed outside the seismic isolation layer 3. [Figure 3] It is an explanatory diagram showing an installation example of the two-layer structure by vertically stacking two units of the basic structure of FIG. 1. (Example 1) [Figure 4] It is an explanatory diagram showing an installation example of the two-layer structure by vertically stacking two units of the basic structure of FIG. 2. (Example 1) [Figure 5] It is an explanatory diagram showing an installation example of the two-layer structure by vertically stacking the basic structure of FIG. 2 on top of the basic structure of FIG. 1. (Example 1) [Figure 6] It is an explanatory diagram showing an installation example of the two-layer structure by vertically stacking the basic structure of FIG. 1 on top of the basic structure of FIG. 2. (Example 1) [Figure 7] It is a simplified diagram of the two-layer structure and a conceptual diagram when the support 6 swings to the right. (Example 1) [Figure 8] It is a simplified diagram similar to FIG. 7 and a conceptual diagram when the support 6 swings to the left. (Example 1) [Figure 9] In FIG. 7, it is a conceptual diagram when the intermediate member 14 is vibrated and seismic-isolated in the left direction. (Example 1) [Figure 10] In FIG. 8, it is a conceptual diagram when the intermediate member 14 is vibrated and seismic-isolated in the right direction. (Example 1) [Figure 11] It is a plan view of the B-B cross-section when the actuator 20 is attached as the vibration device 19. (Example 2) [Figure 12]It is a front view of the A-A cross section when the actuator 20 is attached as the vibration exciter 19. (Example 2) [Figure 13] It is a front view of the A-A cross section when the tuned pendulum type mass damper 30 is attached as the vibration exciter 19. (Example 2) [Figure 14] It is an explanatory diagram when the vibration exciter 19 in FIG. 12 is installed in the lower layer 12 of the two-layer structure in FIG. 3. (Example 2) [Figure 15] It is an explanatory diagram when the vibration exciter 19 in FIG. 13 is installed in the lower layer 12 of the two-layer structure in FIG. 3. (Example 2) [Figure 16] It is an explanatory diagram when the actuator 20 is further attached to the vibration exciter 19 of the two-layer structure in FIG. 15. (Example 2) [Figure 17] It is an explanatory diagram when the basic structure is further stacked on top of the structure in FIG. 16, and a similar vibration exciter 19 is installed in the second layer 36 to form a three-layer structure. (Example 3)

Mode for Carrying Out the Invention

[0015] The present invention is based on the basic forms of FIGS. 1 or 2 which are the conventional basic structures, and the basic structure includes laying the support 6 on the ground or the base. FIG. 1 shows the case where the buoyancy support is installed outside the seismic isolation layer 3 in the basic structure. FIG. 2 shows the case where the buoyancy support is installed inside the seismic isolation layer 3 in the basic structure.

[0016] Before explaining the examples, the floating height of the basic structure will be explained. In the state where the pressurized fluid 4 is not injected into the basic structure, the floating structure body 2 does not float, the seismic isolation support 7 is in a state of landing on the most recessed part of the seismic isolation concave support 7a, and the buoyancy support 8 is in a state of hanging down from the buoyancy support plate 8a. In the hanging state at that time, the floating height is 0, and it is assumed that the distance from the tip of the buoyancy support 8 to the buoyancy support plate 8a is -h. Therefore, when pressurized fluid 4 is injected into the seismic isolation layer 3 from a non-pressurized state and pressurized, the floating structure body 2 will float, and the floating body will stop rising when the buoyancy support 8 and the buoyancy support plate 8a come into contact. At that time the floating body height is +h, and the floating body height is fixed by reducing the pressure of the pressurized fluid 4. With the float at this height +h under pressure, the basic structure achieves the effect of seismic isolation.

[0017] Next, Table 1 describes the resonance experiments of the basic structure in the low-vibration range. [Table 1]

[0018] Table 1 shows the vibration tests conducted on a vibration testing machine (F-1000BDH) using a 450mm x 600mm basic structure. The amplitude displacement was set to 30mm, and vibration tests were performed on the floating structure body 2 with masses of 20kg, 30kg, and 40kg, at sequential vibration frequencies of 1Hz, 2Hz, etc. The degree of vibration of the floating structure body 2 was summarized as the seismic isolation effect. "No seismic isolation effect (×)" means that the amplitude displacements of both parts of the shaking table and the vibration of the floating structure body 2 are of the same magnitude or greater, resulting in resonance and no seismic isolation effect whatsoever. A small seismic isolation effect (△) means that the vibration of the floating structure body 2 was suppressed to less than 15 mm, which is half of the amplitude displacement of the shaking table, indicating that it was slightly seismically isolated. A moderate seismic isolation effect (〇) indicates that the vibration of the floating structure body 2 is suppressed by more than half of the amplitude displacement of the shaking table, which is 15 mm or more, meaning that significant seismic isolation was achieved. A high seismic isolation effect (◎) means that most of the displacement of the shaking table was suppressed, and the vibration of the floating structure body 2 was less than 1 mm, indicating an absolute seismic isolation state.

[0019] According to Table 1, the basic structure, with a total amplitude displacement of 30 mm and a mass of 20 kg, resonates at a frequency of 1 Hz. However, resonance disappears at 2 Hz, indicating some seismic isolation effect. At 3 Hz, the seismic isolation effect is clearly confirmed, and at 4 Hz and above, absolute seismic isolation is achieved. During an experiment with a displacement of 30 mm, a mass of 40 kg, and a vibration frequency of 8 Hz, the ball roller bearing of the basic structural device broke, forcing the vibration testing machine to shut down and the experiment to be stopped. According to the vibration testing machine, the acceleration at 8 Hz was approximately 63,000 mm / sec. 2 (6.4G)

[0020] Table 1 shows that in a basic structure with a planar size of 450 mm x 600 mm and a floating structure body 2 mass of 20 kg or more, resonance occurs in the low vibration range of less than 2 Hz. The following are examples of methods for damping this resonance. [Examples]

[0021] Embodiment 1 of the present invention is a two-layer structure, which will be described below with reference to Figures 3 to 10. Example 1 is a configuration in which an intermediate member 14 is installed to dampen vibrations in the low vibration range, and the fact that a vibration damping effect can be obtained by the intermediate member 14 which is made up of multiple layers is an important point of the present invention.

[0022] Figures 3 to 6 are conceptual diagrams showing how to create a two-tiered structure by using two of the basic structures shown in either Figure 1 or Figure 2 and stacking them vertically in a first and second tier.

[0023] Figures 7 and 8 show a simplified representation of the structure consisting of a support 6, an intermediate member 14, an upper supported member 16, and a sealing material 5, divided into two layers, a lower layer 12 and an upper layer 13. These are conceptual diagrams illustrating the movement of the intermediate member 14 and the upper supported member 16 when the support 6 swings to the right or left. Figures 9 and 10 are conceptual diagrams showing that when the support 6 swings to the left or right in Figures 7 and 8, and the lower layer 12 moves simultaneously, causing the intermediate member 14 to be pulled, applying a force acting in the opposite direction to the swing (right or left) can result in a state where the intermediate member 14 and the upper layer supported member 16 are seismically damped. Note that the intermediate member 14 and the lower layer supported member 15 are the same member. [Examples]

[0024] Embodiment 2 of the present invention is an embodiment in which a vibration device 19 is provided in the two-layer structure, and will be described below with reference to Figures 11 to 16. Embodiment 2 is a two-layer structure in which an actuator 20 or a tuned pendulum-type mass damper 30 is installed as an excitation device 19 for suppressing resonance in the low vibration range and damping vibrations by applying a horizontal force 33 directly below the center of gravity of the intermediate member. The vibration device 19 consists of a sliding sphere 17 which acts as a fulcrum 40 in the transmission of force from the support 6 to the intermediate member 14, and a transmission member 18 which is provided on the sliding sphere 17 and forms the point of force application 41 and the point of application 42 in the transmission of force from the support 6 to the intermediate member 14. The sliding sphere 17 is installed so as to rest tightly on the concave surface of a sliding concave support 17a of the same size without any gaps, and the contact surfaces between them are smooth and have low friction. The sliding sphere 17 and the sliding concave support 17a can be replaced with spherical sliding bearings that can withstand the load of the weight 32.

[0025] Figure 11 is a cross-sectional plan view of the section of the vibration excitation device 19 when the actuator 20 is attached as a vibration excitation device 19 to the lower layer 12 of the structure in Figure 3.

[0026] Figure 12, like Figure 13, is a cross-sectional front view of the vibration excitation device 19 portion when a sliding sphere 17 is fitted into the lower layer 12 of the structure as an excitation device 19, a transmission member 18 is joined to the sliding sphere 17 by screwing it in, and an actuator 20 is attached. By using an actuator 20 with the vibration exciter 19, the degree of low vibration suppression can be adjusted, enabling active operation. The vibration device 19 is installed so that the center of the sliding sphere 17 is directly below the center of gravity 33 of the intermediate member. The actuator 20 is equipped with a directional motor 23, a vibration motor 22, and a slider-crank mechanism 24 on a rotating base 21 on which the motors are mounted. When the actuator 20 detects vibration, it rotates the turntable 21 in a direction that allows for amplitude control using the direction motor 23. Furthermore, the actuator 20 moves the transmission member 18 via the slider-crank mechanism 24 using the vibration motor 22 so that a force acts in the opposite direction to the vibration of the support 6, thereby applying a horizontal force to the point directly below the center of gravity 33 of the intermediate member. The sliding sphere 17 is the pivot point 40, the point of force application 41 is the point of contact between the slider 24c of the slider-crank mechanism 24 and the transmission member 18, and the point of application 42 is the point of contact between the point of contact between the center of gravity 33 of the intermediate member and the transmission member 18. Here, a slider-crank mechanism 24 is used, but any mechanism that can convert the rotational motion of the vibration motor 22 into linear motion is acceptable, not just the slider-crank mechanism 24.

[0027] Figure 13 is a cross-sectional front view of the vibration excitation device 19 portion, in which a sliding sphere 17 is fitted into the lower layer 12 of the two-layer structure as an excitation device 19, a transmission member 18 is passed through the sliding sphere 17, a weight 32 is suspended from the transmission member 18 to form a pendulum, and a synchronized pendulum type mass damper 30 that can synchronize with the natural vibration of the structure is attached to the pendulum. The transmission member 18 is tiltable in any direction on the horizontal plane with the sliding sphere 17 as the pivot point 40, like a mortar and pestle, and can therefore accommodate resonance in any direction. That is, although we have described it in a limited way to horizontal left-right vibrations as shown in Figures 7 to 10, this structure can accommodate resonance in any direction on the horizontal plane. The vibration device 19 is installed with the center of the sliding sphere 17 aligned directly below 33 the center of gravity of the intermediate member.

[0028] As shown in Figure 13, the upper end of the transmission member 18, which forms the point of application, is spherical, and the point of application 42 is the spherical center. A sheath 34 is installed in the portion 33 directly below the center of gravity of the intermediate member that receives the horizontal force from the upper end of the transmission member 18, so as to enclose the upper end of the transmission member 18. The horizontal force is transmitted from the point of application 42 at the upper end of the transmission member 18 through this sheath 34 to the portion directly below the center of gravity of the intermediate member 14. When the lower layer 12 is pressurized and the intermediate member 14 rises, the sheath 34 located directly below the center of gravity 33 of the intermediate member also rises, causing the upper end of the transmission member 18 to relatively descend within this sheath 34. In other words, the upper end of the transmission member 18 moves up and down within this sheath 34 by a distance h, in accordance with the up and down movement of the floating body height in the upper layer 13.

[0029] In Figure 13, the synchronized pendulum-type mass damper 30, which is attached as the excitation device 19 of the structure, is adjusted with a tuning spring 31 so that it resonates with the vibrations in the low vibration range of the basic structure as a synchronized pendulum, and the mass damper is the weight 32 of that pendulum. Here, a tuning spring 31 is used, but any spring that can be adjusted to tune to resonance in the low vibration range will work instead of the tuning spring 31.

[0030] In Figure 13, when the support 6 vibrates from side to side in the low vibration range, the synchronized pendulum-type mass damper 30 also vibrates from side to side in conjunction with it. The lower part of the transmission member 18 that contacts the weight 32 is the point of force application 41, and the spherical center of the upper end of the transmission member 18 that contacts the sheath 34 located directly below the center of gravity of the intermediate member 33 is the point of application 42. The direction of the vibration at the point of application 42 at the upper end of the transmission member 18 is opposite to the direction of the vibration at the point of force application 41 at the lower part of the transmission member 18, which is on the opposite side of the pivot point 40 of the sliding sphere 17. That is, when the support object 6 vibrates horizontally from side to side, the upper end of the transmission member 18 vibrates in the opposite direction, from right to left. As a result, the weight of the counterweight 32 acts as a mass damper that passively suppresses low vibrations.

[0031] Figures 14 to 16 show cases where a synchronized pendulum-type mass damper 30 or an actuator 20 is installed as the vibration excitation device 19 of the structure. In either case, when the support 6 vibrates from side to side in the low vibration range, the point of application 42, which is the upper end of the transmission member 18 that contacts the sheath 34 located directly below the center of gravity position 33 of the intermediate member, vibrates in the opposite direction, from left to right, and the upper part above the upper layer 13 is damped. [Examples]

[0032] Embodiment 3 of the present invention relates to a three-layer structure and will be described below with reference to Figure 17.

[0033] Example 3 is a three-layer structure in which either the basic structure shown in Figure 1 or Figure 2 is vertically stacked on top of the structure of Example 2. In this three-layered structure, as shown in Figure 17, vibration exciters 19 are provided on the first layer 35 and the second layer 36, along with the first intermediate member 38 and the second intermediate member 39. The function and form are the same as the intermediate member 14 in Embodiment 2, and by applying a horizontal force directly below the center of gravity 33 of the second intermediate member, it is possible to further dampen vibrations in the minute low-vibration range. However, even in the case of a three-layer structure, if the use is changed, such as when precise seismic damping is not required, the vibration excitation device 19 may not be installed on the second layer 36 of the three-layer structure. [Explanation of symbols]

[0034] 1: Pressurized floating type slack seismic isolation structure 2: Floating structure body (mass M) 3: Seismic isolation layer 4: Pressurized fluid 5: Sealant 6:Support 7: Seismic isolation bearing 7a: Seismic isolation concave bearing 8: Buoyancy bearing 8a: Buoyancy support plate 9: Bottom extension piece 10: Upper extension piece 11: Multi-layered sagging seismic isolation structure 12: Lower seismic isolation layer (lower layer) 13: Upper seismic isolation layer (upper layer) 14: Intermediate layer (intermediate member) 15: Lower layer supported member 16: Upper layer supported member 17: Sliding Sphere 17a: Sliding concave bearing 18: Transmission member 19: Vibration device 20: Actuator 21: Rotating stand 22: Vibration motor 23: Directional motor 24: Slider crank mechanism 24a: Crank Wheel 24b: Connecting rod 24c: Slider 25: Gear shift 26: Rack 27: Pinion 30: Synchronized pendulum-type mass damper 31: Synchronization spring 32: Weight (mass m1 or m2) 33: Directly below the center of gravity of the intermediate layer (intermediate member) 34: Sheath 35: 1st stage seismic isolation layer (1st layer) 36:Second-stage seismic isolation layer (second layer) 37: 3rd stage seismic isolation layer (3rd layer) 38: First stage intermediate layer (first stage intermediate member) 39: Second stage intermediate layer (second stage intermediate member) 40:Fulcrum 41: Effort 42: Point of action

Claims

1. A seismic isolation structure that supports the floating structure body (2), which is the object to be seismically isolated, Each of the loosened sealing material (5) forms a pressurized floating body, and the structure comprises an upper layer (13) and a lower layer (12) that can be stacked vertically. Between the upper layer (13) sealing material (5) and the lower layer (12) sealing material (5), an intermediate member (14) is interposed, which is buoyantly supported by a support (6). The device comprises a sliding sphere (17) which acts as a fulcrum in the transmission of force from the support (6) to the intermediate member (14), and a transmission member (18) provided on the sliding sphere (17) which forms the point of force application and the point of load application in the transmission of force from the support (6) to the intermediate member (14). Multi-layered sagging seismic isolation structure (11).

2. The lower layer (12) includes a lower layer supported member (15) as an intermediate member (14) that is supported by the support (6) through buoyancy. The upper layer (13) includes an upper support member (16) that is supported by buoyancy on the intermediate member (14) and supports the object (2), Each of the support structure (6) and the lower support member (15) is provided with lower extension pieces (9, 10) that extend horizontally and face each other in the vertical direction. The intermediate member (14) and the upper support member (16) each have upper extension pieces (9, 10) that extend horizontally and face each other in the vertical direction. The lower layer (12) sealing material (5) is interposed between the lower layer extension pieces (9, 10), The upper layer (13) sealing material (5) is interposed between the upper layer extension pieces (9, 10). The multi-layered sagging seismic isolation structure (11) according to claim 1.

3. The system includes a vibration device (19) that applies a horizontal force from the support (6) to the intermediate member (14), The transmission member (18) is tiltable in any direction relative to the horizontal plane with the sliding sphere (17) as a pivot point, and is in contact directly below the center of gravity of the intermediate member (14). The multi-layered sagging seismic isolation structure (11) according to claim 1 or 2.

4. The vibration excitation device (19) includes an actuator (20) that orients the rotating table (21) in a direction that allows vibration control, and an actuator (20) that applies a horizontal force to the intermediate member (14). The multi-layered sagging seismic isolation structure (11) according to claim 3.

5. The vibration exciter (19) includes a weight (32) suspended from the transmission member (18) and configured to synchronize with the natural vibration of the multi-layer slack seismic isolation structure (11), The multi-layered sagging seismic isolation structure (11) according to claim 3.

6. It comprises a first layer (35) as a lower layer (12), a second layer (36) as an upper layer (13), and a third layer (37) which is made into a pressurized floating body using a loosened sealing material (5) and is stacked on top of the first and second layers (35) and (36) as an upper layer (13) when the second layer (36) is the lower layer (12), Between the sealing material (5) of the first layer (35) and the sealing material (5) of the second layer (36), a first intermediate member (38) is interposed, which is buoyantly supported by the support (6). Between the sealing material (5) of the second layer (36) and the sealing material (5) of the third layer (37), a second intermediate member (39) is interposed, which is buoyantly supported by the first intermediate member (38) which acts as a support. Of the first intermediate member (38) and the second intermediate member (39), at least the first intermediate member (38) is provided with the vibration device (19) described in claims 3 to 5, a sliding sphere (17) as a fulcrum in the transmission of force from the support to the intermediate member, and a transmission member (18) provided on the sliding sphere (17) that forms the point of force application and the point of load application in the transmission of force from the support to the intermediate member. The multi-layered sagging seismic isolation structure (11) according to claim 1 or 2.

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