Seismic isolation structure

Abstract

To provide a seismic isolation structure capable of lengthening the natural period without lengthening tension members.SOLUTION: A seismic isolation structure 1 provided between a lower structure 2 and an upper structure 3 includes a fixed structure 10 fixed to one of the lower structure 2 and the upper structure 3, a movable structure 20 horizontally movably supported by the other of the lower structure 2 and the upper structure 3, a tension member 30 connected to a fixed structure end 10b of the fixed structure 10 and to a movable structure end 20c of the movable structure 20, and a tilting member 40 that is tiltably connected to each of the lower structure 2, the upper structure 3, and the movable structure 20.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a seismic isolation structure provided between a lower structure and a superstructure. [Background technology]

[0002] 2. Description of the Related Art In structures such as buildings, it is known that a seismic isolation structure is provided between a substructure, such as a foundation, and a superstructure in order to reduce vibrations transmitted from the ground during an earthquake.

[0003] A known example of such a seismic isolation structure has been one which has a number of diagonal bars fixed to a lower structure, a number of inverted diagonal bars fixed to an upper structure, and tension members (connecting members) connected to an upper casing provided at the upper ends of the diagonal bars and a lower casing provided at the lower ends of the inverted diagonal bars and positioned lower than the upper casing, in which the upper structure is supported by the tension members in a simple pendulum manner relative to the lower structure (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2-35141 Summary of the Invention [Problem to be solved by the invention]

[0005] In general, the seismic isolation performance of a seismic isolation structure can be improved by lengthening the natural period. In the above-mentioned conventional seismic isolation structure, the natural period is determined by the length of the pendulum formed by the tension member, so in order to obtain higher seismic isolation performance, it is necessary to make the tension member longer.

[0006] However, in order to lengthen the tensile members in the above-mentioned conventional seismic isolation structure, it is necessary to increase the vertical space between the substructure and the superstructure. This requires increasing the height of the first floor of the building and deepening the base of the foundation, which increases the cost of installing the seismic isolation structure.

[0007] An object of the present invention is to provide a seismic isolation structure that can lengthen the natural period without lengthening the tension members. [Means for solving the problem]

[0008] The seismic isolation structure of the present invention is a seismic isolation structure provided between a lower structure and an upper structure, and is characterized in having a fixed structure fixed to either the lower structure or the upper structure, a movable structure supported on the other of the lower structure or the upper structure so as to be freely movable in the horizontal direction, a tension member connected to a fixed structure end of the fixed structure and a movable structure end of the movable structure, and a tilting member connected to each of the lower structure, the upper structure, and the movable structure so as to be freely tiltable.

[0009] In the seismic isolation structure of the present invention, in the above-mentioned configuration, the tilting material may be connected to either the lower structure or the upper structure at one end so as to be freely tiltable, and connected to the other of the lower structure or the upper structure at the other end, and may be connected to the movable structure between the one end and the other end so as to be freely tiltable.

[0010] In the seismic isolation structure of the present invention, in the above-mentioned configuration, the tilting material may be tiltably connected at one end to either the lower structure or the upper structure, tiltably connected to the movable structure at the other end, and tiltably connected to a support material fixed to either the lower structure or the upper structure between the one end and the other end.

[0011] In the above-mentioned configuration, the seismic isolation structure of the present invention may be connected to either the lower structure or the upper structure at one end so as to be freely tiltable, connected to the movable structure at the other end so as to be freely tiltable, and connected to the fixed structure between the one end and the other end so as to be freely tiltable. Effect of the Invention

[0012] According to the present invention, it is possible to provide a seismic isolation structure that can lengthen the natural period without lengthening the tensile members. [Brief description of the drawings]

[0013] [Figure 1] 1 is a front view showing a schematic configuration of a seismic isolation structure according to a first embodiment of the present invention. [Diagram 2] 2 is a front view showing a state in which the seismic isolation structure shown in FIG. 1 is performing a seismic isolation operation. [Diagram 3] FIG. 6 is a front view showing a schematic configuration of a seismic isolation structure according to a second embodiment of the present invention. [Figure 4] 4 is a front view showing a state in which the seismic isolation structure shown in FIG. 3 is performing a seismic isolation operation. [Diagram 5] FIG. 11 is a front view showing a schematic configuration of a seismic isolation structure according to a third embodiment of the present invention. [Figure 6] 6 is a front view showing a state in which the seismic isolation structure shown in FIG. 5 is performing a seismic isolation operation. [Figure 7] 2 is a front view showing a schematic configuration of a modified example of the seismic isolation structure according to the first embodiment shown in FIG. 1, in which the structure is turned upside down. [Figure 8] 1. FIG. 4 is a front view showing a schematic configuration of a modified example of the seismic isolation structure according to the first embodiment shown in FIG. [Figure 9] FIG. 9 is a perspective view showing a schematic configuration of the seismic isolation structure shown in FIG. 8. [Figure 10] 1. FIG. 4 is a plan view that illustrates a schematic configuration of another modified example of the base isolation structure according to the first embodiment illustrated in FIG. [Figure 11] FIG. 11 is a front view of the seismic isolation structure shown in FIG. [Figure 12] FIG. 11 is a cross-sectional view taken along the line AA in FIG. [Figure 13] 11 is a front view showing a state in which the seismic isolation structure shown in FIG. 10 is performing a seismic isolation operation. FIG. [Figure 14] FIG. 11 is a diagram showing an example of an arrangement between a lower structure and an upper structure of the seismic isolation structure shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a seismic isolation structure according to the present invention will be described in detail with reference to the drawings.

[0015] As shown in Fig. 1, a seismic isolation structure 1 according to a first embodiment of the present invention is provided between a substructure 2 and an upper structure 3. The seismic isolation structure 1 can reduce horizontal vibrations transmitted from the ground to the upper structure 3 via the substructure 2.

[0016] A plurality of seismic isolation structures 1 can also be arranged between the lower structure 2 and the upper structure 3. The arrangement pattern and the number of arrangements when a plurality of seismic isolation structures 1 are arranged between the lower structure 2 and the upper structure 3 can be changed as appropriate.

[0017] The substructure 2 is a structure directly or indirectly fixed to the ground. The superstructure 3 is a structure constructed above the substructure 2. In this embodiment, the substructure 2 is the foundation of a building, and the superstructure 3 is a building such as a building, a warehouse, or a wooden structure.

[0018] In addition, the substructure 2 is not limited to the foundation of a building, and may be any other structure, such as a part constituting the lower floor of a building, as long as it is a structure fixed to the ground. When the substructure 2 is a part constituting the lower floor of a building, the superstructure 3 is a part constituting the upper floor of the building.

[0019] The seismic isolation structure 1 comprises a fixed structure 10, a movable structure 20, a tension member 30 and a tilting member 40.

[0020] The fixing structure 10 is fixed to either the lower structure 2 or the upper structure 3. In this embodiment, the fixing structure 10 is fixed to the lower structure 2.

[0021] The fixed structure 10 can be configured to include, for example, a column section 10a configured as a column extending in the vertical direction, and a fixed structure end section 10b provided at the upper end section of the column section 10a so as to protrude horizontally like a beam, and fixed to the upper surface of the lower structure 2 at the lower end of the column section 10a. The fixed structure 10 is configured, for example, using steel material or the like, so as to have a predetermined rigidity capable of supporting a combination of loads transmitted to the fixed structure 10, including the self-weight of the upper structure 3, live load, earthquake load, wind load, and the like.

[0022] As long as the fixing structure 10 has a fixing structure end 10b and is configured to be fixed to either the lower structure 2 or the upper structure 3, the shape or configuration is not limited to an L-shape in which the fixing structure end 10b is cantilevered from the end of a single pillar portion 10a, but can be variously modified, for example, to a truss structure or a gate-shaped structure.

[0023] The movable structure 20 is supported by the other of the lower structure 2 and the upper structure 3 (the one to which the fixed structure 10 is not fixed) so as to be freely movable in the horizontal direction. In this embodiment, the movable structure 20 is supported by the upper structure 3 so as to be freely movable in the horizontal direction. The movable structure 20 is freely movable in any horizontal direction relative to the upper structure 3, and supports a vertical force applied from the upper structure 3.

[0024] The movable structure 20 may be configured to include, for example, a column section 20a configured as a column extending in the vertical direction, a base section 20b provided at the upper end of the column section 20a, and a movable structure end section 20c provided at the lower end of the column section 20a in a beam-like manner on both sides in the horizontal direction, and may be configured to be supported on the lower surface of the upper structure 3 at the base section 20b so as to be freely movable in the horizontal direction. In this case, in order to support the movable structure 20 so as to be freely movable in any horizontal direction relative to the upper structure 3, a support mechanism 21 such as a linear rolling bearing (CLB) or a roller mechanism may be provided between the base section 20b and the lower surface of the upper structure 3. The support mechanism 21 that supports the movable structure 20 on the lower surface of the upper structure 3 so as to be freely movable in the horizontal direction is not limited to the linear rolling bearing (CLB) or roller mechanism described above, and may have various configurations as long as it can support the movable structure 20 so as to be freely movable in any horizontal direction relative to the upper structure 3.

[0025] The movable structure end 20c is disposed at a lower position than the fixed structure end 10b. The movable structure 20 is configured, for example, using a steel material or the like, so as to have a predetermined rigidity capable of supporting a combination of loads transmitted to the movable structure 20, including the weight of the upper structure 3 and the seismic isolation structure 1, live load, earthquake load, wind load, and the like.

[0026] As long as the movable structure 20 has a movable structure end portion 20c and is supported on either the lower structure 2 or the upper structure 3 so as to be freely movable in the horizontal direction, the shape or configuration can be modified in various ways, such as a truss structure, a gate structure, etc., rather than being limited to an inverted T-shape in which a base portion 20b is provided at the upper end of a single pillar portion 20a and movable structure ends 20c are provided at the lower end thereof so as to protrude on both sides.

[0027] The tension member 30 is disposed in a vertical position, and its upper end is connected to the fixed structure end 10b of the fixed structure 10, and its lower end is connected to the movable structure end 20c of the movable structure 20. In this way, the tension member 30 suspends and holds the movable structure 20 supported by the upper structure 3 relative to the fixed structure 10 fixed to the lower structure 2. The tension member 30 can be, for example, a rod-shaped member made of steel or the like, extending in the up-down direction (vertical direction), and having a tensile strength capable of supporting a combination of loads transmitted to the tension member 30, including the weights of the upper structure 3 and the movable structure 20, live loads, earthquake loads, wind loads, etc., but may also be a wire, chain, etc. having a tensile strength capable of supporting the loads.

[0028] The tension member 30 is connected to each of the fixed structure end 10b and the movable structure end 20c by, for example, a connection structure using a universal joint, a connection structure using a ring member, a pin connection, etc., so that the tension member 30 can tilt (rotate) freely in any horizontal direction. As a result, when the lower structure 2 vibrates horizontally relative to the upper structure 3 due to an earthquake or the like, the tension member 30 tilts in the vibration direction like a pendulum between the fixed structure end 10b and the movable structure end 20c due to the vibration.

[0029] The tilting member 40 is connected to each of the lower structure 2, the upper structure 3, and the movable structure 20 so as to be able to tilt freely. In this embodiment, the tilting member 40 is formed in a rod shape having a predetermined rigidity capable of transmitting a horizontal load generated when the lower structure 2 vibrates in the horizontal direction relative to the upper structure 3 to the movable structure 20. The tilting member 40 is connected at its lower end (one end side) to the lower structure 2 by a connecting mechanism 41 such as a connecting structure using a universal joint, a connecting structure using a ring member, or a pin connection, and is able to tilt (rotate) freely in any horizontal direction relative to the lower structure 2. Similarly, the tilting member 40 is connected at its upper end (the other end side) to the upper structure 3 by a connecting mechanism 42 such as a connecting structure using a universal joint, a connecting structure using a ring member, or a pin connection, and is able to tilt (rotate) freely in any horizontal direction relative to the upper structure 3. Furthermore, the tilting member 40 is connected between the upper end and the lower end (between one end side and the other end side) to the side end of the movable structure end 20c of the movable structure 20 opposite to the part to which the tension member 30 is connected by a connecting mechanism 43 such as a connecting structure using a universal joint, a connecting structure using a ring member, or a pin connection, and is freely tiltable (rotatable) in any direction horizontally relative to the movable structure 20. As a result, when the lower structure 2 vibrates horizontally relative to the upper structure 3 due to an earthquake or the like, the vibration causes the tilting member 40 to tilt in the vibration direction between the lower structure 2 and the upper structure 3, and the tilting can move the movable structure 20 horizontally relative to the upper structure 3 (in the same direction as the vibration). In addition, the connection portion of the tilting member 40 to the movable structure 20 is not limited to the side end portion opposite the portion to which the tensile member 30 is connected of the movable structure end portion 20c of the movable structure 20, but may be various portions of the movable structure 20, such as, for example, near the connection portion of the movable structure end portion 20c with the tensile member 30, the central portion of the movable structure end portion 20c, the column portion 20a, or other protruding portions provided on the column portion 20a.

[0030] In order to prevent an axial load from the tilting member 40 from being transmitted to the lower structure 2 and the upper structure 3 when the tilting member 40 tilts between the lower structure 2 and the upper structure 3, an appropriate configuration is provided, for example, by configuring some or all of the connecting mechanisms 41, 42 and 43 so that the tilting member 40 passes through them, thereby supporting the tilting member 40 so as to be freely tiltable relative to the lower structure 2, the upper structure 3 or the movable structure 20 while supporting it so as to be freely movable relative to the lower structure 2, the upper structure 3 or the movable structure 20 in the axial direction, or by configuring the tilting member 40 so as to be freely expandable and contractible, for example, like a double tube structure.

[0031] As shown in Figure 2, in the seismic isolation structure 1 of this embodiment having the above-mentioned configuration, when the lower structure 2 vibrates horizontally relative to the upper structure 3 due to an earthquake or the like, the tension member 30 performs seismic isolation operation by tilting in the vibration direction like a pendulum between the fixed structure end 10b and the movable structure end 20c due to the vibration, thereby suppressing the transmission of vibrations of the lower structure 2 to the upper structure 3.

[0032] In addition, in the seismic isolation structure 1 of this embodiment having the above-mentioned configuration, the movable structure 20 is supported so as to be freely movable in the horizontal direction relative to the superstructure 3, and the tilting member 40 is connected so as to be freely tiltable to each of the lower structure 2, the upper structure 3, and the movable structure 20. Therefore, when the lower structure 2 vibrates horizontally relative to the upper structure 3 due to an earthquake or the like, as shown in Fig. 2, the tilting member 40 tilts with the vibration, and the movable structure 20 moves horizontally in the vibration direction relative to the upper structure 3 with the tilting of the tilting member 40. At this time, if the vertical distance between the connecting mechanism 41 and the connecting mechanism 43 is 1, the vertical distance between the connecting mechanism 41 and the connecting mechanism 42 is α (α>1), and the amplitude of the horizontal vibration of the lower structure 2 relative to the upper structure 3 is x, the movable structure 20 moves horizontally by x / α, and the amplitude of the tension member 30 tilting in the vibration direction like a pendulum between the fixed structure end 10b and the movable structure end 20c is x / α. Therefore, if the pendulum length of the tension member 30 is L and the supporting weight of the tension member 30 is mg, the restoring force F of the tension member 30 is 1 is F 1= mgx / αL, and from the balance of the forces of the tilting member 40, the horizontal restoring force F of the lower structure 2 to the upper structure 3 is 2 F 2 =F 1 ×1 / α=mgx / α 2 L, and the horizontal stiffness k of the lower structure 2 relative to the upper structure 3 is k=F 2 / x=mg / α 2 Therefore, the horizontal period of the lower structure 2 relative to the upper structure 3 is T = 2π(m / k) 1 / 2 =2πα(L / g) 1 / 2 Therefore, the natural period of the seismic isolation structure 1 for horizontal vibration is α times (α>1) that of a conventional structure that vibrates only with the tension member 30 of length L without using the tilting member 40. The magnification of the period T can be changed by changing the vertical position of the connection part between the tilting member 40 and the movable structure 20.

[0033] In this way, in the seismic isolation structure 1 of this embodiment, the movable structure 20 is supported so as to be freely movable horizontally relative to the upper structure 3, and the tilting member 40 is connected to each of the lower structure 2, the upper structure 3, and the movable structure 20 so as to be freely tiltable, so that the natural period of the seismic isolation structure 1 during seismic isolation operation can be lengthened without lengthening the tension member 30.

[0034] Furthermore, in the seismic isolation structure 1 of this embodiment having the above-mentioned configuration, the natural period of the seismic isolation structure 1 during seismic isolation operation can be lengthened without lengthening the tension member 30, so there is no need to increase the first floor height of the building or deepen the position of the base of the foundation in order to expand the vertical space between the lower structure 2 and the upper structure 3, thereby reducing the cost of installing the seismic isolation structure 1.

[0035] In this way, according to the seismic isolation structure 1 of this embodiment, the natural period can be lengthened and the seismic isolation performance of the seismic isolation structure 1 can be improved without increasing installation costs.

[0036] As a second embodiment of the present invention, the seismic isolation structure 1 may be configured such that the tilting member 40 is tiltably connected at one end to either the lower structure 2 or the upper structure 3, tiltably connected at the other end to the movable structure 20, and tiltably connected to a support member 50 fixed to either the lower structure 2 or the upper structure 3 between the one end and the other end. Fig. 3 shows, as the second embodiment of the present invention, a seismic isolation structure 1 configured such that the tilting member 40 is tiltably connected at the upper end (one end side) to the underside of the upper structure 3 by a connecting mechanism 42, tiltably connected at the lower end (other end side) to the movable structure end 20c of the movable structure 20 by a connecting mechanism 41, and tiltably connected between the upper end and the lower end to a support member 50 fixed to the lower structure 2 by a connecting mechanism 43.

[0037] The support member 50 may be configured to include, for example, a column portion 50a configured in a columnar shape extending in the vertical direction, and a beam portion 50b provided at the upper end of the column portion 50a so as to protrude horizontally in a beam-like shape, and may be configured to be fixed to the upper surface of the substructure 2 at the lower end of the column portion 50a. The support member 50 is configured to have a predetermined rigidity capable of supporting the tilting member 40 that tilts, for example, by using a steel material or the like. The support member 50 may also be configured to be integral with the fixed structure 10, for example, by sharing the column portion 50a with the column portion 10a of the fixed structure 10 and having the beam portion 50b protruding from the column portion 10a of the fixed structure 10.

[0038] In the seismic isolation structure 1 of the second embodiment, when the lower structure 2 vibrates horizontally relative to the upper structure 3 due to an earthquake or the like, the tension member 30 performs seismic isolation by tilting in the vibration direction between the fixed structure end 10b and the movable structure end 20c like a pendulum due to the vibration, as shown in Fig. 4, and the tilting member 40 tilts with the vibration, and the movable structure 20 moves horizontally in the vibration direction relative to the upper structure 3, so that the natural period of the seismic isolation structure 1 during seismic isolation operation can be lengthened without lengthening the tension member 30. In the case of the second embodiment, the vertical distance between the connecting mechanism 41 and the connecting mechanism 43 is set to 1, and the vertical distance between the connecting mechanism 43 and the connecting mechanism 42 is set to α, so that the natural period of the seismic isolation structure 1 can be set to α times (α>1) the natural period of a conventional structure that vibrates only with the tension member 30 of length L without using the tilting member 40.

[0039] As a third embodiment of the present invention, the seismic isolation structure 1 may be configured such that the tilting member 40 is tiltably connected at one end to either the lower structure 2 or the upper structure 3, tiltably connected at the other end to the movable structure 20, and tiltably connected to the fixed structure 10 between the one end and the other end. Fig. 5 shows, as the third embodiment of the present invention, a seismic isolation structure 1 configured such that the tilting member 40 is tiltably connected at the upper end (one end side) to the underside of the upper structure 3 by a connecting mechanism 42, tiltably connected at the lower end (other end side) to the movable structure end 20c of the movable structure 20 by a connecting mechanism 41, and tiltably connected to the side end of the fixed structure end 10b of the fixed structure 10 by a connecting mechanism 43 between the upper end and the lower end.

[0040] In the seismic isolation structure 1 of the third embodiment, when the lower structure 2 vibrates horizontally relative to the upper structure 3 due to an earthquake or the like, the tension member 30 tilts in the vibration direction like a pendulum between the fixed structure end 10b and the movable structure end 20c due to the vibration, as shown in Fig. 6, and the tilting member 40 tilts with the vibration, and the movable structure 20 moves horizontally in the vibration direction relative to the upper structure 3, so that the natural period of the seismic isolation structure 1 during seismic isolation can be lengthened without lengthening the tension member 30. In the case of the third embodiment, the vertical distance between the connecting mechanism 41 and the connecting mechanism 43 is the length L of the tension member 30, so by setting the vertical distance between the connecting mechanism 43 and the connecting mechanism 42 to αL, the natural period of the seismic isolation structure 1 can be set to α times (α>1) the natural period of a conventional structure that vibrates only with the tension member 30 of length L without using the tilting member 40.

[0041] In the third embodiment, the connecting mechanism 41 and the connecting mechanism 43 may be configured to have a connecting structure using a universal joint, a connecting structure using a ring member, a pin connection, or the like, so that the tilting member 40 also serves as the tension member 30. In this case, the tension member 30 may be omitted.

[0042] The seismic isolation structures 1 shown in Figs. 1, 3, and 5 can all be configured upside down, that is, configured such that the fixed structure 10 is fixed to the lower surface of the upper structure 3, and the movable structure 20 is supported on the upper surface of the lower structure 2 so as to be freely movable in the horizontal direction. Fig. 7 shows a configuration in which the seismic isolation structure 1 according to the first embodiment shown in Fig. 1 is upside down. In the seismic isolation structure 1 shown in Fig. 7, the fixed structure 10 is fixed to the lower surface of the upper structure 3, and the movable structure 20 is supported on the upper surface of the lower structure 2 by a support mechanism 21 so as to be freely movable in the horizontal direction. In addition, the tension member 30 is connected at its lower end to the fixed structure end portion 10b at the lower end of the fixed structure 10 so as to be freely tiltable, and at its upper end to the movable structure end portion 20c at the upper end of the movable structure 20 so as to be freely tiltable. Furthermore, the tilting member 40 is tiltably connected at its lower end to the upper surface of the lower structure 2 by a connecting mechanism 41, tiltably connected at its upper end to the lower surface of the upper structure 3 by a connecting mechanism 42, and tiltably connected between its lower end and upper end to the side end of the movable structure end 20c of the movable structure 20 by a connecting mechanism 43. In the configuration shown in Fig. 7, which is upside down in this way, as in the case of the configuration shown in Fig. 1, by setting the vertical distance between the connecting mechanisms 42 and 43 to 1 and the vertical distance between the connecting mechanisms 41 and 42 to α, the natural period of the seismic isolation structure 1 can be set to α times (α>1) the natural period of a conventional structure that vibrates only with the tension member 30 of length L without using the tilting member 40.

[0043] Fig. 8 is a front view showing a schematic configuration of a modified example of the seismic isolation structure 1 according to the first embodiment shown in Fig. 1, and Fig. 9 is a perspective view showing a schematic configuration of the seismic isolation structure 1 shown in Fig. 8. In Fig. 8 and Fig. 9, the same reference numerals are used to designate members corresponding to the members described above.

[0044] The seismic isolation structures 1 shown in Figures 1, 3, and 5 are all minimum configurations that produce a seismic isolation effect, and are unstable as configurations that support the upper structure 3 relative to the lower structure 2 so that it can move freely in the horizontal direction. Therefore, a configuration is required that can stably support the upper structure 3 relative to the lower structure 2 so that it can move freely in the horizontal direction.

[0045] The seismic isolation structure 1 shown in Figures 8 and 9 uses a fixed structure 10 consisting of four pillar sections 10a connected by four fixed structure end sections 10b, and a movable structure 20 consisting of four pillar sections 20a connected to two movable structure end sections 20c connected perpendicular to each other. Tensile members 30 (four in total) are connected between each of the four fixed structure end sections 10b and the protruding portions of the movable structure end sections 20c. The tilting member 40 is supported at its lower end by a connecting mechanism 41 so as to be freely tiltable on the lower structure 2, and at its upper end by a connecting mechanism 42 so as to be freely tiltable on the upper structure 3, with the intermediate portion supported so as to be freely tiltable by a connecting mechanism 43 provided at the intersection of the movable structure end sections 20c. In this case, the connecting mechanism 42 and the connecting mechanism 43 are each configured as a through hole through which the tilting member 40 passes, and are configured to support the tilting member 40 so that it can be tilted in any horizontal direction, and also to support the tilting member 40 so that it can move freely relative to the tilting member 40 in the axial direction.

[0046] According to this configuration of the seismic isolation structure 1, the fixed structure 10 and the movable structure 20 are securely supported by the lower structure 2 and the upper structure 3, respectively, so that the upper structure 3 can be stably supported relative to the lower structure 2 and freely moved horizontally.

[0047] Fig. 10 is a plan view showing a schematic configuration of another modified example of the seismic isolation structure 1 according to the first embodiment shown in Fig. 1, Fig. 11 is a front view of the seismic isolation structure 1 shown in Fig. 10, Fig. 12 is a cross-sectional view taken along line AA in Fig. 10, and Fig. 13 is a front view showing the seismic isolation structure 1 shown in Fig. 10 in a state in which the seismic isolation operation is being performed. Note that in Figs. 8 and 9, the same reference numerals are used to designate members corresponding to those described above.

[0048] As a more preferable configuration for stably supporting the upper structure 3 relative to the lower structure 2 so as to be freely movable in the horizontal direction, the configurations shown in Figs. 10 to 12 can also be adopted.

[0049] The seismic isolation structure 1 shown in Figures 10 to 12 uses a fixed structure 10 in which the upper ends of four pillars 10a are connected by four fixed structure ends 10b, and a movable structure 20 in which the lower ends of four pillars 20a are connected by four movable structure ends 20c, and the upper ends of the four pillars 20a are connected by four bases 20b. The fixed structure 10 and the movable structure 20 each have a rectangular shape in a plan view, and are arranged with their long sides perpendicular to each other. A tension member 30 (four in total) is connected between each of the two fixed structure end portions 10b on the long side and each of the two movable structure end portions 20c on the long side, and the tilting member 40 is supported at its lower end by a connecting mechanism 41 so as to be freely tiltable on the lower structure 2, and at its upper end by a connecting mechanism 42 so as to be freely tiltable on the upper structure 3, while the intermediate portion is supported at its intermediate portion by a connecting mechanism 43 consisting of a sleeve supported between the two movable structure end portions 20c on the long side.

[0050] 10 to 12, a linear roller bearing (CLB) is used as the support mechanism 21. In this case, the support mechanism 21 has two lower guide rails 21a fixed parallel to each other on the upper surface of the base 20b, two upper guide rails 21b fixed to the lower surface of the upper structure 3 in an orientation perpendicular to the lower guide rails 21a, and two sliders 21c slidably attached to the corresponding lower guide rails 21a and upper guide rails 21b, and the movable structure 20 can move horizontally relative to the upper structure 3 by moving the sliders 21c along the lower guide rails 21a and upper guide rails 21b.

[0051] 10 to 12, a spherical bearing is used as the connecting mechanism 43 that connects the tilting member 40 to the movable structure 20 in a tiltable manner. Specifically, the connecting mechanism 43 is formed in a spherical shape with the tilting member 40 passing through and fixed to the axis of the connecting mechanism 43, and is supported on a spherical surface provided on the movable structure 20 in a rotatable manner.

[0052] Even in the configuration of the seismic isolation structure 1 shown in Figures 10 to 12, when the lower structure 2 vibrates horizontally relative to the upper structure 3 due to an earthquake or the like, the tension member 30 performs seismic isolation operation by tilting in the vibration direction like a pendulum between the fixed structure end 10b and the movable structure end 20c due to the vibration, as shown in Figure 13, and the tilting member 40 tilts in conjunction with the vibration, and the movable structure 20 moves horizontally in the direction of vibration relative to the upper structure 3, so that the natural period of the seismic isolation structure 1 during seismic isolation operation can be lengthened without lengthening the tension member 30.

[0053] 10 to 12, the fixed structure 10 and the movable structure 20 are reliably supported by the lower structure 2 and the upper structure 3, respectively, so that the upper structure 3 can be stably supported so as to be freely movable in the horizontal direction relative to the lower structure 2. Furthermore, according to the configuration of the seismic isolation structure 1 shown in Figs. 10 to 12, the movable structure 20 has a box-like configuration in which the upper and lower ends of the four pillars 20a are connected by four movable structure ends 20c and four bases 20b, respectively, so that the rigidity of the movable structure 20 can be increased and the movable structure 20 can be reliably supported by the support mechanism 21 on the upper structure 3 so as to be freely movable in the horizontal direction.

[0054] A configuration in which four of the seismic isolation structures 1 shown in Figures 10 to 12 are arranged in a set between the lower structure 2 and the upper structure 3. In this case, by arranging the four seismic isolation structures 1 in a rectangle of two rows and two columns in a plan view as shown in Figure 14, the four seismic isolation structures 1 can stably support the upper structure 3 relative to the lower structure 2 so that it can move freely in the horizontal direction.

[0055] The present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the spirit and scope of the present invention. [Explanation of symbols]

[0056] 1. Seismic isolation structure 2 Substructure 3 Superstructure 10 Fixed structure 10a Pillar 10b Fixed structure end 20 Movable structure 20a Pillar 20b base 20c Movable structure end 21 Support mechanism 21a Lower guide rail 21b Upper guide rail 21c slider 30 Tensile material 40 Tilting material 41 Connection mechanism 42 Connection mechanism 43 Connection mechanism 50 Support material 50a Pillar 50b Beam section

Claims

1. A seismic isolation structure provided between a lower structure and an upper structure, a fixed structure fixed to either the lower structure or the upper structure; a movable structure supported on the other of the lower structure and the upper structure so as to be movable in a horizontal direction; A tension member connected to a fixed structure end of the fixed structure and a movable structure end of the movable structure; a tilting member tiltably connected to each of the lower structure, the upper structure, and the movable structure; A seismic isolation structure comprising:

2. The tilting member is One end of the structure is connected to either the lower structure or the upper structure so as to be able to tilt freely, The other end side is connected to the other of the lower structure and the upper structure so as to be able to tilt freely, The seismic isolation structure according to claim 1 , wherein the movable structure is connected to the one end side and the other end side so as to be able to tilt freely.

3. The tilting member is One end of the lower structure is connected to the other of the upper structure so as to be able to tilt freely, The other end is connected to the movable structure so as to be tiltable, The seismic isolation structure according to claim 1 , wherein the structure is connected between the one end side and the other end side to a support member fixed to either the lower structure or the upper structure so as to be able to tilt freely.

4. The tilting member is One end of the lower structure is connected to the other of the upper structure so as to be able to tilt freely, The other end is connected to the movable structure so as to be tiltable, The seismic isolation structure according to claim 1 , wherein the seismic isolation structure is connected to the fixed structure between the one end side and the other end side so as to be able to tilt freely.

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