JP2023124221A - Base isolation device - Google Patents

Abstract

To provide a base isolation device capable of equalizing bearing pressure and preventing an allowable load from being reduced.SOLUTION: A base isolation device comprises: a sliding plate installed on one of a superstructure and a substructure; and a bearing body which is on the other of the superstructure and the substructure and slides on the sliding plate. The bearing body is provided with a sliding material which has a concave shape with a central section thereof recessed from a peripheral section thereof in a direction away from the sliding plate and is arranged so as to slide on the sliding plate. When being subject to a vertical load, the sliding material deforms from the concave shape to a flat shape.SELECTED DRAWING: Figure 2

Description

TECHNICAL FIELD The present invention relates to a seismic isolation device used in a seismic isolation structure for structures including structures such as buildings, detached houses, and bridges, and machinery devices.

A seismic isolation device is installed between the ground and the building in order to protect structures such as buildings from vibrations caused by dynamic loads caused by earthquakes, typhoons, etc., such as seismic motions caused by earthquakes. It is known that

Various types of laminated rubber, sliding bearings, rolling bearings, etc. are known as seismic isolation devices. As sliding bearings, elastic sliding bearings, such as laminated rubber bearings having laminated rubber or the like, which are used together with seismic isolation support devices capable of elastic displacement in the horizontal direction, are becoming popular.

The elastic sliding bearing device has a smooth stainless steel sliding plate provided on the ground side, and an elastic sliding bearing body slidably disposed on the sliding plate.

An elastic sliding bearing generally has a circular or rectangular sliding member on the lower surface of a laminate made of metal plates and soft plates such as rubber. slides on the slide plate. The elastic slide bearing is tightly connected to an upper structure such as a building via a flange fixed to the upper surface of the laminate.

In such a sliding bearing device, when an earthquake or vibration occurs, the sliding member in the elastic sliding bearing body slides on the sliding plate, which is the mating member, and absorbs the displacement caused by the earthquake or vibration. This greatly reduces the vibrations transmitted to superstructures such as buildings.

By the way, in the structure of a conventional sliding bearing, it is installed between a lower structure such as a foundation and an upper structure such as a building, and a vertical load from the upper structure is applied to the elastic sliding bearing.

The sliding member is designed so that the entire sliding surface that slides on the sliding plate is uniform. The vertical load is concentrated in the center of

In particular, it is known that if the sliding member has a large diameter, bending deformation or the like occurs in the peripheral portion of the sliding member, and the degree of bearing stress of the sliding member becomes uneven between the central portion and the peripheral portion. . As a result, even when the elastic sliding bearing slides on the sliding plate, the surface pressure is concentrated on the central portion of the sliding member, and there is a possibility that only the central portion where the surface pressure is concentrated is worn.

For example, in Cited Document 1, in a normal state in which a vertical load from an upper structure such as a building is not significantly applied, when a horizontal force due to shaking acts, the distribution of compressive stress changes to that of the sliding layer at the bottom of the sliding bearing. It is disclosed that it is larger at the center and smaller at the outer periphery. In other words, compressive stress acts in a wide distribution around the center of the sliding layer, and in this state, when the horizontal force increases and the bearing vibrates, the central part of the sliding layer where the compressive stress is large wears. However, it becomes non-uniform between the central portion and the peripheral portion.

On the other hand, in the sliding bearing of Patent Document 2, a structure is disclosed in which a concave portion is provided in the central portion of the lower surface of the sliding member so that the central portion of the lower surface of the sliding member does not come into contact with the sliding member. With this configuration, even if the elastic sliding bearing slides on the sliding plate and even if the surface pressure concentrates on the central portion, the central portion does not contact the sliding plate, so the elastic sliding bearing can slide without wear. It has a seismic isolation effect.

JP-A-2003-113896 JP 2004-169715 A

However, in the sliding bearing of Patent Document 2, the sliding member has a recess in the central portion where the vertical load concentrates, and the central portion does not come into contact with the sliding plate. Although it can be avoided, this part cannot receive a vertical load.
In other words, although this sliding bearing can prevent central wear due to concentration of surface pressure on the central portion of the sliding member, it cannot secure the central portion of the surface pressure (compressive stress), and the sliding member is divided into concave areas. There was a problem that the allowable load of the

SUMMARY OF THE INVENTION It is an object of the present invention to provide a seismic isolation device capable of uniformizing surface pressure and preventing reduction of allowable load.

a slide plate provided on one of the upper structure and the lower structure;
a bearing body provided on the other of the upper structure and the lower structure and sliding on the slide plate;
has
The bearing body is
a sliding member held in a concave shape in which a center portion is spaced apart from the slide plate more than an outer peripheral portion, and is disposed slidably with respect to the slide plate;
The sliding member adopts a configuration that receives a vertical load and deforms from the concave shape to a flat shape.

ADVANTAGE OF THE INVENTION According to this invention, while being able to equalize contact pressure, the seismic isolation apparatus which can prevent reduction in an allowable load is realizable.

BRIEF DESCRIPTION OF THE DRAWINGS It is a whole perspective view which shows an example of the seismic isolation apparatus of one embodiment of this invention. 1 is a vertical cross-sectional view showing a main configuration of a seismic isolation device according to an embodiment of the present invention; FIG. FIG. 4 is a vertical cross-sectional view showing the main configuration of a seismic isolation device arranged between an upper structure and a lower structure; 1 is a perspective view showing an example of a deformed hard plate according to one embodiment of the present invention; FIG. FIG. 4 is a perspective view showing a modification of the modified hard plate according to one embodiment of the present invention; It is a longitudinal section showing modification 1 of a seismic isolation device of one embodiment of the present invention. It is a longitudinal section showing modification 2 of a seismic isolation device of one embodiment of the present invention. It is a longitudinal section showing modification 3 of a seismic isolation device of one embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is an overall perspective view showing an example of a seismic isolation device according to one embodiment of the present invention. In the present embodiment, expressions indicating directions such as up and down used to describe the configuration and operation of each part of the seismic isolation device are not absolute but relative. It is appropriate when each part of is in the posture shown in the figure, but if the posture changes, it should be interpreted according to the change in posture. The top and bottom may be reversed.

A seismic isolation device 1 shown in FIG. 1 is an elastic sliding bearing that is arranged between an upper structure and a lower structure to provide a seismic isolation bearing for the upper structure.

FIG. 2 is a vertical cross-sectional view showing the main structure of the seismic isolation device, and FIG. 3 is a longitudinal cross-sectional view showing the main structure of the base isolation device arranged between the upper structure and the lower structure. is.

The seismic isolation device 1 has a slide bearing main body 4 and a slide plate 5 .

In this embodiment, as shown in FIG. 2, the seismic isolation device 1 has a sliding bearing main body 4 fixed to a building (upper structure) 20 and a sliding plate 5 fixed to a foundation (lower structure) 30 side. be done.

The basic performance of the seismic isolation device 1 is that, in the event of a small or medium-sized earthquake, the laminate 7 of the slide bearing main body 4 undergoes horizontal shear deformation to mitigate the seismic force, and in the event of a large earthquake, the sliding member of the slide bearing main body 4 8 slides on the slide plate 5 to absorb and reduce the seismic force with frictional energy.

The seismic isolation device 1 is arranged, for example, between a building 20 as an upper structure and a foundation 30 as a lower structure together with a plurality of laminated rubber bearing bodies as other seismic isolation members. The seismic isolation device 1, together with other seismic isolation members, has a support (bearing) function that stably supports the building 20, a damping function that absorbs seismic energy to reduce shaking of the building 20, and a It functions as a vibration isolation system with a restoration function that restores the horizontal position of the

As other seismic isolation members, in addition to the laminated rubber bearing, for example, a laminated rubber with a plug, a high-damping laminated rubber, a rolling bearing, or the like may be used. As the seismic isolation member, a damper without a support function such as an oil damper, a steel damper, a lead damper, or other seismic isolation member such as a displacement suppression device that has only a horizontal displacement suppression function without a load bearing function. A device may be used.

Note that the seismic isolation device 1 may be placed directly below the pillars of the building 20 as the upper structure and between the foundation 30 as the lower structure, or between the four corners of the building 20 and the foundation 30. good.

The seismic isolation device 1 has a seismic isolation function and a support function of supporting a vertical load (which may be a column load) from the building 20 in normal times.

Even when the sliding member 8 and the sliding plate 5 slide and move relative to each other, the seismic isolation device 1 receives and supports the vertical load of the building 20 evenly over the entire surface of the sliding member 8. 20 can be moved in the horizontal direction (horizontal direction in FIG. 3) relative to the foundation (lower structure) 30 .

<Sliding bearing body 4>
The sliding bearing main body 4 is an elastic sliding bearing, and includes a laminate 7 having a laminated rubber portion 6, a connecting steel plate 72, and an end steel plate (holding member) 74, and a sliding member 8, each of which deforms in the height direction. formed as possible. The laminated rubber portion 6 has a plurality of deformed hard plates 76 in multiple layers.

In the sliding bearing main body 4, the sliding members 8, the end steel plates 74, and the deformation are arranged so that the contact pressure distribution on the sliding members 8 at the bottom of the sliding bearing main body 4 becomes uniform when a vertical load is applied from the upper structure. A hard plate 76 is formed.
Of the sliding member 8, the end steel plates 74, and the deformed hard plate 76, at least the sliding member 8 and the end steel plates 74 are formed in a concave shape in which the central portion is more distant from the sliding plate 5 than the outer peripheral portion. At least the sliding member 8 and the end steel plate 74 are formed in a deformable lower concave shape and also formed in a deformable convex shape projecting upward (may also be referred to as an “upper convex shape”). It can be said that it is.

In the sliding bearing main body 4, in addition to the sliding member 8 and the end steel plate 74, the deformable hard plate 76 is also formed in a deformable concave shape (or "convex shape"). The sliding member 8, the end steel plate 74, and the deformable hard plate 76 are formed so that the central portion (central portion) side is positioned higher than the outer peripheral portion, and deforms when subjected to a vertical load to absorb the vertical load from the outer peripheral portion. It is a shape that disperses to the side. That is, the deformable hard plate 76 together with the sliding member 8 and the end steel plates 74 are formed, for example, in an upward convex shape that is deformable. The sliding member 8, the end steel plate 74, and the deformable hard plate 76 are formed in a concave shape in which the central portion (central portion) side is separated from the sliding plate 5 rather than the outer peripheral portion. Distributes the vertical load to the outer peripheral side.

The sliding member 8, the end steel plate 74, and the deformable hard plate 76 are arranged so that the center portion side of the sliding plate 5 is closer to the stacking direction side than the outer peripheral portion side in a state where the sliding bearing main body 4 does not receive a load along the stacking direction. It is formed to form a concave shape spaced apart (for example, downward).
Specifically, the sliding member 8, the end steel plate 74, and the deformed hard plate 76 are formed in a shape in which the height level gradually increases upward from the outer peripheral portion toward the axial center.

The load along the stacking direction is the vertical load applied to the slide bearing main body 4 when installed in a structure (between upper and lower structures).

Also, the concave shape may be curved or conical. When the sliding bearing main body 4 receives a vertical load, the concavely formed elements such as the sliding member 8, the end steel plate 74, and the deformation hard plate 76 are deformed into a flat shape by the vertical load. are distributed from the center side to the outer peripheral side. Specifically, when the concave end steel plate 74 and the deformed hard plate 76 receive a vertical load including the load from the upper structure, they are deformed so as to receive the received load on their entire surfaces perpendicular to each other and become a sliding member. Distribute the load so that the surface pressure distribution at 8 is uniform.

The sliding member 8, the end steel plate 74, and the deformed hard plate 76 are formed in a hemispherical dome shape. That is, in addition to the sliding member 8 and the end steel plate 74, the deformed hard plate 76 is curved downward toward the central portion to form a concave shape. As a result, in addition to the sliding member 8 and the end steel plate 74, the deformed hard plate 76 has the highest surface pressure in the sliding bearing main body 4 and is less likely to wear when the sliding bearing main body 4 receives a load along the stacking direction. The intense central surface pressure (contact surface pressure) is reduced to even out wear.

In the present embodiment, the sliding bearing main body 4 deforms the deformable hard plate 76 in addition to at least the lower surfaces of the sliding member 8 and the end steel plates 74 to flatten the sliding member 8 when subjected to a vertical load. is formed to

In the laminate 7 , connecting steel plates 72 and end steel plates 74 are joined to both ends fixed to the upper and lower ends of the laminated rubber portion 6 .

The laminated rubber portion 6 is joined to the flange portion 42 via a connecting steel plate 72 , and the sliding member 8 is joined to the end steel plate 74 . The connecting steel plate 72 and the flange portion 42 may be configured integrally. In the sliding bearing main body 4 , the sliding members 8 are fitted to the end steel plates 74 with their lower surfaces protruding from the end steel plates 74 .

The laminated rubber portion 6 has a columnar body in which a plurality of deformable elastic plates 62 and deformable hard plates 76 are alternately laminated and integrated. covered with The covering portion 66 is made of a rubber material or the like having excellent weather resistance, and protects the elastic plate 62 and the deformed hard plate 76 from the external environment. They may be integrated by sulfur bonding.

Also, the covering portion 66 may be formed by applying an adhesive to the outer peripheral surfaces of the elastic plate 62 and the deformable hard plate 76 and pasting them together, or may be formed by a wound self-bonding tape. . The outer peripheral edge portions of the upper and lower ends of the laminated rubber portion 6 respectively protrude in the vertical direction and cover the outer periphery of each of the connecting steel plate 72 and the end steel plate 74 . The laminated rubber portion 6 is integrally bonded to connecting steel plates 72 and end steel plates 74 disposed at its upper and lower ends.

FIG. 4 is a perspective view showing an example of the modified hard plate 76 of the present invention.
The deformable hard plate 76 is a deformable plate-like body and corresponds to a so-called intermediate steel plate. The deformed hard plate 76, together with the sliding member 8 and the end steel plates 74, has, for example, a dome shape in which the lower surface side of the plate material is concave downward, in other words, a dome shape in which the upper surface side of the plate material is convex upward. , and has an opening serving as a positioning hole 78 in the center. The dome-shaped deformed hard plate 76 shown in FIG. 4 is deformed by receiving a vertical load and becomes flat.

The deformed hard plate 76 has an inner peripheral portion 76b positioned higher than an outer peripheral portion 76a and has a higher height level. The deformable hard plate 76 is deformed by a load applied from above, and deforms into a flat shape in the horizontal direction. When deformed, the deformable hard plate 76 is deformed so that a uniform load is applied to the entire surface of the sliding member 8 below.

The deformed hard plate 76 is arranged such that the central portion of the deformed hard plate 76 is positioned away from the sliding plate 5 in the lamination direction of the elastic plate 62 and the deformed hard plate 76 rather than the outer peripheral portion when the slide bearing main body 4 is not subjected to a vertical load. is formed to have a curved shape. Then, the deformable hard plate 76 deforms into a flat shape while the slide bearing main body 4 receives a vertical load, and disperses the vertical load from the central portion side to the outer peripheral portion side. With this configuration, the deformable hard plate 76 deforms under a vertical load to reduce the load transmitted downward. When the slide plate 5 is located above the deformed hard plate 76 , the deformed hard plate 76 is used upside down so that the outer peripheral portion 76 a contacts the slide plate 5 .

The deformed hard plate 76 has a non-flat shape, for example, a conical shape as shown in FIG. It may be formed to have a shape. In the seismic isolation device having this configuration, the sliding member 8 and the end steel plate 74 may also be formed in a non-flat shape, for example, in a conical shape, and the surface pressure distribution in the sliding member 8 is such that the deformed hard plate 76A, the end steel plate 74 Due to the deformation of the central steel plate 74, the stress is distributed uniformly over the entire surface without concentrating on the central portion.

The deformed hard plate 76 may be, for example, a steel plate, a metal plate such as a ceramic, a plastic, a fiber-reinforced plastic, or a non-metal plate. In the case of a steel plate, it may be formed by pressing or the like so that the steel plate is curved into a dome shape, and when it is made of a resin such as plastic, it may be formed by molding.

The elastic plate 62 is an annular plate material formed corresponding to the shape of the deformed hard plate 76 , and follows the shape of the deformed hard plate 76 and has the same shape as the deformed hard plate 76 .

Examples of the elastic plate 62 include, but are not limited to, rubber materials such as natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber, ethylene-propylene rubber, butyl rubber, halogenated butyl rubber, and chloroprene rubber. These synthetic resins, a mixture of rubber and synthetic resin, or the like may be used.

A positioning hole 78 is provided through the central portion of the laminated rubber portion 6 (the elastic plate 62, the deformable hard plate 76, and the covering portion 66) to be used during manufacturing. are provided as necessary, and may be omitted. The positioning holes 78 may be left empty, filled with an elastic material, or may be inserted with damping plugs such as lead plugs. An end steel plate 74 is attached to the lower end of the central portion of the laminated rubber portion 6 .

The connecting steel plates 72 are arranged together with the end steel plates 74 so as to sandwich the laminated portion of the elastic plate 62 and the deformed hard plate 76 . The connecting steel plate 72 fixes the laminate 7 to the flange portion 42 . It is preferable that the connecting steel plate 72 and the flange portion 42 are formed in a flat shape in a state where the slide bearing main body 4 is not subjected to a vertical load.
The connecting steel plate 72 and the flange portion 42 are formed in a plate shape or columnar shape with flat upper and lower surfaces. The connecting steel plate 72 is formed in a disk shape or an annular shape, and the flange portion 42 is formed in a disk shape, a polygonal plate shape, a columnar shape, or a polygonal columnar shape. The connecting steel plates 72 are fixed so as to be laminated in close contact with the flange portion 42 .

The end steel plate 74 is arranged on the sliding member 8 which is a low-friction material, and positions and holds the sliding member 8 in the sliding bearing main body 4 . One of the upper and lower surfaces of the end steel plate 74, here both the upper and lower surfaces are formed to correspond to the shape of the sliding member 8, that is, the lower concave shape. In this embodiment, the end steel plate 74 attaches the sliding member 8 to the laminate 7, and may be called a mounting bracket.

The end steel plate 74 constitutes the lower portion of the laminate 7 . The end steel plate 74 has the sliding member 8 attached to its lower surface. The end steel plate 74 abuts the sliding plate 5 fixed to one of the upper structure (building 20) and the lower structure (foundation 30) (foundation 30) via the sliding member 8. and is slidably arranged on the slide plate 5 .

In the end steel plate 74 , at least a lower surface 74 a disposed on the sliding member 8 of the upper and lower surfaces has a shape corresponding to the shape of the sliding member, that is, the surface shape, and deforms as the sliding member 8 deforms.

Both the lower surface 74 a and the upper surface 74 b of the end steel plate 74 may have a shape corresponding to the shape of the sliding member 8 . As a result, the central portion of the entire end steel plate 74 bends downward due to the load applied to the end steel plate 74 from above, and the deformation is transmitted to the sliding member 8 on the lower surface. That is, the end steel plate 74 receives a load from above and deforms from a lower concave shape to a flat shape, thereby deforming the sliding member 8 from a lower concave shape to a flat shape.

The end steel plate 74 has a recess 742 on its lower surface, and the sliding material 8 is arranged on the bottom surface (lower surface of the end steel plate) 74a in the recess 742 .

A sliding member 8 is fitted in the concave portion 742 of the end steel plate 74 and is fitted with an adhesive, a bolt, or the like.

In the sliding bearing main body 4 , the sliding member 8 is fitted into the end steel plates 74 , so that when the sliding bearing main body 4 is horizontally deformed during an earthquake, the horizontal force generated in the sliding member 8 is transferred to the end steel plates 74 . I can tell you. At the same time, it prevents the creep phenomenon (cold flow) in which the sliding material 8 spreads in the recessed portion 742 and becomes thin under load support.

A bottom surface 74 a of the concave portion 742 (the bottom surface of the end steel plate 74 ) has a shape corresponding to the curved surface of the top surface of the sliding member 8 .
The end steel plate 74 and the sliding member 8 are deformed by a load from above (mainly a vertical load, but a horizontal load may also be applied), and the sliding member 8 is also deformed. As long as they deform into a flat shape, they do not have to be adhered to each other.

A cap plate 79 is attached to the bottom surface 74 a of the concave portion 742 of the end steel plate 74 to close the central positioning hole 78 . The cap plate 79 is attached by fitting into a recess provided in the bottom surface 74a. This cap plate 79 closes the positioning hole 78, makes the bottom surface 74a a continuous surface, and increases the area of the bottom surface 74a to which the sliding member 8 adheres. can be attached to Also, the cap plate 79 can prevent cold flow of the sliding material 8 from entering the positioning hole 79 .

In the present embodiment, the end steel plate 74 has a shape corresponding to the shape of the sliding member 8 and deforms similarly to the deformation of the sliding member 8 .

If the sliding member 8 is dome-shaped, the end steel plate 74 is also formed dome-shaped. The end steel plate 74 has the same shape as the sliding member 8, and is preferably deformed into a flat shape by a load from above (mainly a vertical load). When a vertical load is applied, both are similarly deformed into a flat shape. It is more preferable if it has a shape with the same radius of curvature as the sliding member 8 .

Also, when a load including a vertical load (for example, the vertical load itself) is applied, the end steel plate 74 is deformed by being received by the entire surface extending in the horizontal direction, and the sliding member 8 is also deformed along with this deformation. As a result, the central portion bends downward and forms a flat shape together with the sliding member 8 . At this time, the sliding member 8 has a uniform surface pressure distribution.

Further, the connecting steel plate 72, the end steel plate 74, and the deformed hard plate 76 are usually made of steel plate due to adhesion to the rubber portion of the laminated rubber portion 6, but a nickel plate, a copper plate, a brass plate, or a nickel plated plate is used. , copper-plated, and brass-plated steel sheets can be used.

The flange portion 42 may have any cross-sectional shape such as a rectangular shape, a disk shape, an elliptical shape, or a polygonal shape in a plane cross section. In the present embodiment, an example will be described in which the flange portion 42 is formed in a disc shape and has a larger outer diameter than the laminated rubber portion 6 together with the connecting steel plate 72 and the end steel plate 74 .

The flange portion 42 fixes the laminate 7 to the other structure (the building 20 ) of the building (upper structure) 20 and the foundation (lower structure) 30 via the connecting steel plates 72 . The flange portion 42 is joined to the building 20 via bolts inserted into bolt holes provided on the outer peripheral side, and is inserted into bolt holes provided on the inner peripheral side at predetermined intervals in the circumferential direction. The laminate 7 is joined via bolts.

When the seismic isolation device 1 is arranged between the building 20 and the foundation 30 and receives a vertical load, the sliding member 8 disperses the vertical load and completely disperses the vertical load on the bottom surface 81 that is the sliding surface. is provided so as to have a uniform surface pressure distribution. The sliding member 8 uniformly contacts the sliding plate 5 over the entire surface.

The sliding member 8 is formed in a concave shape that is depressed downward in the stacking direction at the central portion. The sliding member 8 has lower concave upper and lower surfaces that are recessed downward, in other words, the sliding member 8 has upper and lower convex upper and lower surfaces that protrude upward. It can be said that it has The sliding member 8 has a dome shape and is provided integrally with an end steel plate 74 having a shape matching the shape of the sliding member 8 .

In the present embodiment, the sliding member 8 may be made of resin such as fluororesin such as PTFE (polytetrafluoroethylene), or may be made of nylon. Also, the sliding material 8 may be configured by coating the bottom surface of the end steel plate 74 with a fluororesin, or by attaching a polyacetal plate.

The sliding member 8 preferably has a thickness (for example, a resin thickness) t of about 3 to 6 mm, and may be formed in a dome shape with a thickness of 4 mm or 5 mm. If the sliding member 8 is formed in a dome shape with a thickness t larger than 6 mm, the shape becomes excessively thick and costly. Also, if the dome-shaped sliding member 8 is thicker, the degree of protrusion of the outer peripheral portion of the sliding member 8 from the recess 742 is greater than that of the central portion. In the seismic isolation device 1, if the building supported above is lighter than initially set, or if it moves up and down due to an earthquake or the like, the outer peripheral portion of the sliding member 8 may wear first.

As a result, the outer peripheral portion (portion indicated by w) of the end steel plate 74 located on the outer peripheral side of the sliding member 8 approaches the sliding plate 5 side and may come into contact with the sliding plate 5 . If it is 6 mm or less, even if the outer peripheral portion of the sliding member 8 wears, the central portion contacts the sliding plate 5 before the end steel plate 74 contacts the sliding plate 5 to transmit the vertical load. Even in such an extremely rare condition that the outer peripheral portion of the sliding member 8 wears earlier than the central portion, the outer peripheral portion of the end steel plate 74 does not come into contact with the sliding plate 5 . On the other hand, if the thickness of the sliding member 8 is less than 3 mm, there is a possibility that the sliding member 8 is too thin and wears out early, resulting in a problem of lack of durability. For example, if the thickness of the sliding member 8 is 3 mm to 6 mm, even if the length w of the outer peripheral portion of the end steel plate 74 is 10 mm, it will be deformed by a vertical load and the central portion will contact the sliding plate 5 to form a flat shape. become.

The sliding member 8 may be formed in any manner as long as it is a member that has a small coefficient of friction and is suitably slidable when it contacts and slides on the sliding plate 5 . The sliding member 8 may be formed of one piece, or may be formed integrally by laminating a plurality of thin plate-like members into a dome shape and attached to the bottom surface of the end steel plate 74 .

Moreover, the sliding member 8 may be held in a concave shape in the bearing body 4 so that the central portion is spaced apart from the sliding plate 5 rather than the outer peripheral portion, and the sliding member 8 may be arranged so as to be slidable with respect to the sliding plate 5 . The sliding material 8 may be made of synthetic resin such as PTFE, nylon, or the like in the form of a flexible flat sheet, attached to the end steel plate 74 or the like, and configured to be held in a concave shape. . In this configuration, the sliding member 8 deforms from a concave shape to a flat shape by receiving a vertical load and deforming the end steel plates 74 and the like. According to this configuration, it is not necessary to process the sliding member 8 itself into a concave shape or the like, and the manufacturing cost of the sliding member itself can be reduced.

<Sliding plate 5>
The sliding plate 5 is fixed to the foundation 30 and slidably contacts the sliding bearing main body 4 fixed to the building 20 .

The sliding plate 5 has a sliding surface portion 51 against which the sliding material 8 of the sliding bearing body 4 is slidably abutted. The sliding surface portion 51 has an outer diameter larger than the outer diameter of the sliding bearing main body 4 . The sliding plate 5 is laid on the upper surface of the reinforcing plate 53 and is provided integrally with the reinforcing plate 53 .

The sliding plate 5 (sliding surface portion 51) is fixed on the reinforcing plate 53 with a fixing member such as a bolt. As the sliding plate 5, a stainless steel plate is used in consideration of rusting due to moisture and the like, and in particular, a plate whose surface is mirror-finished by buffing or the like (for example, #400 finish) is often used. , but not limited to this. The slide plate 5 may be coated with a fluorine resin or the like having a low sliding resistance, or clad steel may be used. Here, the clad steel is a clad made of a steel material as a base material, in which a certain metal is entirely coated with another metal, and the interface between the metals is metallographically bonded. The sliding plate 5 may be made of engineering plastics, non-ferrous metals, etc., as long as the rigidity can be maintained.

In addition, although the reinforcing plate 53 is formed in a rectangular shape in this embodiment, it is not limited thereto, and may be in the shape of a disk, an ellipse, or a polygonal plate. The reinforcing plate 53 is fixed to the upper surface of the foundation 30 . The reinforcing plate 53 is fixed integrally with a base plate (not shown) embedded in the foundation 30 by inserting bolts (not shown) into bolt holes formed at four corners where the sliding plate 5 is not arranged. ing. The base plate may, for example, be embedded in the concrete of the foundation 30 with the top exposed.

<Operation of seismic isolation device 1>
In the seismic isolation device 1, the deformed hard plate 76 and the end steel plate 74 in the laminate 7 and the sliding member 8 are formed so as to deform into a flat shape.

The seismic isolation device 1 is arranged between an upper structure (building 20) and a lower structure (foundation 30), and is subjected to a vertical load.

By applying a vertical load, in the laminated body 7, the deformed hard plate 76 and the end steel plates 74 are deformed such that the central portion thereof is bent downward. For example, the deformed hard plate 76 and the end steel plate 74 are deformed into a flat shape. When the deformed hard plate 76 and the end steel plate 74 are deformed, the deformed bulging portion 66 a protrudes from the outer periphery of the laminated rubber portion 6 in the laminated rubber portion 6 , thereby deforming the deformed hard plate 76 and/or the end steel plate 74 . is absorbed, the vertical load is distributed horizontally and applied to the sliding member 8, and the sliding member 8 is also deformed into a flat shape.

As a result, when a vertical load is applied to the sliding member in the conventional elastic sliding bearing, the stress concentrated in the central portion of the surface pressure distribution of the sliding member is dispersed according to the surface pressure distribution of the laminate.

Therefore, the surface pressure distribution in the sliding member 8 is uniform without being concentrated in the central portion, and the coefficient of friction can be stabilized. That is, in the sliding member 8, the contact surface pressure at the central portion, which has the highest surface pressure and is the most worn, is reduced, and the entire surface of the sliding member 8 including the central portion and the outer peripheral portion can be uniformly worn.

In the present embodiment, the sliding member 8 has a thickness of 3 to 6 mm, and is formed in a dome-shaped concave curved surface with both upper and lower surfaces recessed downward. By using a dome-shaped sliding member with a thickness of 3 to 6 mm, when the sliding member 8 is deformed, the surface pressure can be applied to the entire sliding surface of the sliding member 8, and the surface pressure is distributed uniformly. be able to.

Further, the slide bearing main body 4 can be suitably used repeatedly without the central portion of the slide member 8 being worn out due to temperature rise caused by sliding with the slide plate 5, thereby preventing deterioration of repeated performance. It can improve performance.

The lower surface of the slide bearing main body 4 is formed of a sliding member 8 having a concave shape and a thickness of 3 mm to 6 mm. They are arranged in a state of protruding 1.5 mm to 3 mm along the radius of the sphere. By defining the thickness of the sliding member 8, it is possible to form the sliding member 8 that becomes flat when a predetermined load is applied from above.

In a seismic isolation device 1 installed between a building 20 and a foundation 30, the sliding member 8 is not completely flat and slides on the sliding plate 5 while being in contact with the sliding plate 5 at the outer peripheral portion. Suppose there was a case. In this case, even if the outer peripheral portion of the sliding member 8 wears earlier than the central portion due to sliding with the sliding plate 5 , the sliding member 8 is removed before the end portion of the end steel plate 74 contacts the sliding plate 5 . The central portion of the contacts the sliding plate 8 and slides thereon.

Therefore, the end steel plate 74 does not slide on the slide plate 5 , and damage to the slide plate 5 or the end steel plate 74 due to sliding between the end steel plate 74 and the slide plate 5 can be prevented.

According to the seismic isolation device 1 of the present embodiment, the contact surface pressure received by the sliding member 8 in the sliding bearing main body 4 can be made uniform, and the allowable load corresponding to the outer shape of the sliding member 8 is Reduction of allowable load can be prevented. In addition, the sliding member 8 is prevented from being locally worn, resulting in a seismic isolation device with excellent durability.

In the seismic isolation device 1 of the present embodiment, the deformable hard plate 76, the end steel plate 74, and the sliding member 8 are configured to have a dome shape that deforms into a flat shape upon receiving a load from above. It suffices that the surface pressure distribution in the sliding member 8 becomes uniform when it receives the stress. Therefore, at least one of the deformed hard plate 76, the end steel plate 74, and the sliding member 8 is formed in a dome shape (curved shape) so that when a vertical load is applied, the stress is not concentrated in the center, and the stress is uniformly distributed. can do.

A seismic isolation device 1A shown in FIG. 6 has a configuration in which the deformation hard plate 76A is changed to a flat shape in the configuration of the seismic isolation device 1. FIG. The seismic isolation device 1A has a flat deformed hard plate 76A, a curved sliding member 8, and a curved end steel plate 74 (protruding upward). That is, the outer peripheral portion 761a and the inner peripheral portion (central portion) 761b of the deformed hard plate 76A have the same height level, and the outer peripheral portion and the inner peripheral portion of the sliding member 8 and the end steel plate 74 have the same height level. The peripheral portion has a shape that protrudes toward the side away from the slide plate 5 . With this configuration, in the seismic isolation device 1A, the surface pressure distribution in the sliding member 8 may be made uniform when a load along the stacking direction, for example, a vertical load is received.

Further, in the seismic isolation device 1B shown in FIG. 7, in the configuration of the seismic isolation device 1, some of the deformed hard plates 76 are flat hard plates. Thereby, in the seismic isolation device 1B, when a vertical load is applied as a load along the stacking direction, the load may be transmitted downward to make the surface pressure distribution in the sliding member 8 uniform.

The seismic isolation device 1B has both a curved deformed hard plate 76 and a flat deformed hard plate 76B as a plurality of deformed hard plates laminated to form a laminate 7B in the slide bearing main body 4B. The seismic isolation device 1B further includes a curved sliding member (for example, a dome-shaped sliding member) 8 and a curved end steel plate (a convex shape, for example, a dome shape) provided curvedly. 74 and has a complex shape. In the structure of the plurality of deformed hard plates in the seismic isolation device 1B, in the laminated rubber portion 6, a flat deformed hard plate 76B is laminated on the upper part (three in the figure), and a concave deformed hard plate 76B is laminated on the lower part. 76 are stacked (three sheets in the figure).

As a result, when the seismic isolation device 1B is arranged between the building 20 and the foundation 30 and the sliding bearing main body 4 receives a vertical load as a load along the stacking direction from above, the load is applied to the laminated rubber portion. 6 is received by a flat deformed hard plate 76B. When the load is transmitted downward, it is transmitted from the deformed hard plate 76B to the deformed hard plate 76 below and deformed, and the surface pressure distribution in the sliding member 8 becomes uniform. can play.

Further, in the embodiment and Modifications 1 and 2, the sliding plate 5 is provided on the foundation side and the bearing main body 4 is provided on the building side. As shown in the device 1C, the sliding plate 5 may be provided on the building side and the bearing body 4C may be provided on the foundation side. In FIG. 8, the same configurations as those of the seismic isolation device of the present embodiment shown in FIG.

In FIG. 8, in the seismic isolation device 1C, the sliding plate 5 is provided integrally with the reinforcing plate 53 and fixed to the building (lower structure) 20 side. A slide bearing main body 4</b>C that slides on the slide plate 5 is fixed to a foundation (lower structure) 30 .

Note that the support body 4C has a configuration in which the support body 4 is turned upside down, and like the support body 4, it has a laminate 7C and a sliding member 8C. In the laminated body 7C, end steel plates 74 and connecting steel plates 72 are joined to both ends fixed to the upper and lower ends of the laminated rubber portion 6, respectively. The laminated rubber portion 6 is joined to the flange portion 42 via a connecting steel plate 72 , and the end steel plate 74 is joined to the sliding member 8</b>C.

In the sliding bearing main body 4C, for example, the sliding member 8C, the end steel plate 74, and the deformable hard plate 76C are also formed in a deformable concave shape (or "convex shape").
The sliding member 8</b>C is held in a recessed shape in which the central portion is more distant from the sliding plate 5 than the outer peripheral portion, and is arranged slidably with respect to the sliding plate 5 .

The sliding member 8C configured in this manner is formed in a concave shape that is depressed downward so that the central portion (central portion) side is positioned lower than the outer peripheral portion together with the end steel plate 74 and the deformed hard plate 76C. . The sliding member 8C, the end steel plate 74, and the deformable hard plate 76C are shaped to deform when receiving a vertical load and distribute the vertical load to the outer peripheral side. A sliding member 8 is arranged on a surface 74 a (upper surface of the end steel plate 74 ) inside the recess 742 on the upper surface of the end steel plate 74 .

The bearing main body 4C has a sliding member 8C which is held in a concave shape in which the central portion is spaced apart from the slide plate 5 more than the outer peripheral portion, and which is arranged slidably with respect to the slide plate 5 . The sliding member 8C receives a vertical load and deforms from a concave shape to a flat shape. For example, in the bearing main body 4C, the load is evenly dispersed from the central portion side to the outer peripheral portion side through the upper surface 81C of the sliding member 8C. Thereby, the same effect as each embodiment can be obtained.

In this embodiment, the recessed shapes of the sliding members 8, 8C, the end steel plates 74, and the deformed hard plates 76, 76A, 76C deform the sliding members 8, 8C subjected to a vertical load into flat shapes. If so, they may be formed with different curvatures instead of a uniform shape.

It should be considered that the embodiments disclosed this time are illustrative in all respects and not restrictive. The scope of the present invention is indicated by the scope of the claims rather than the above description, and is intended to include all modifications within the scope and meaning equivalent to the scope of the claims.

The above descriptions are illustrative of preferred embodiments of the invention, and the scope of the invention is not limited thereto. In other words, the description of the configuration of the seismic isolation devices 1, 1A, 1B, and 1C and the shape of each part is an example, and it is clear that various modifications and additions to these examples are possible within the scope of the present invention. be.

The seismic isolation device according to the present invention has the function of an elastic sliding bearing, and can have a seismic isolation effect against seismic motions larger than an unexpected large earthquake. It is useful as a seismic isolation device that can be arranged in layers.

1, 1A, 1B, 1C Seismic isolation device 4 Slide bearing main body (bearing main body)
5 Slide Plate 6 Laminated Rubber Section 7 Laminate 8, 8C Slide Material 20 Building (Superstructure)
30 foundation (substructure)
42 flange portion 51 sliding surface portion 53 reinforcing plate 62 elastic plate 66 coating portion 66a deformed swelling portion 72 connecting steel plate 74 end steel plate (holding member)
74a Lower surface 76, 76A, 76B, 76C Deformed hard plate (hard plate)
76a outer peripheral portion 76b inner peripheral portion (central portion)
78 Positioning hole 79 Cap plate

Claims (8)

a slide plate provided on one of the upper structure and the lower structure;
a bearing body provided on the other of the upper structure and the lower structure and sliding on the slide plate;
has
The bearing body is
a sliding member held in a concave shape in which a center portion is spaced apart from the slide plate more than an outer peripheral portion, and is disposed slidably with respect to the slide plate;
The sliding material receives a vertical load and deforms from the concave shape to a flat shape.
Seismic isolation device. The sliding material is formed in the concave shape,
The seismic isolation device according to claim 1. The bearing body is
a holding member having one of the upper and lower surfaces formed in a concave shape, the holding member contacting the sliding member to position and hold the sliding member;
The holding member receives the vertical load and deforms from a concave shape to a flat shape, thereby deforming the sliding member into a flat shape.
A seismic isolation device according to claim 1 or 2. The support body has the holding member on one of the upper and lower parts, is formed by alternately laminating a plurality of elastic plates and hard plates, and is shear deformable in a horizontal direction orthogonal to the lamination direction. having a laminate,
A seismic isolation device according to claim 3. At least one of the plurality of hard plates is a concave hard plate that deforms into a flat shape upon receiving the vertical load.
The seismic isolation device according to claim 4. The concave shape is curved,
A seismic isolation device according to any one of claims 1 to 5. The concave shape is dome-shaped,
A seismic isolation device according to any one of claims 1 to 5. The sliding material is formed in a dome shape with a thickness of 3 mm to 6 mm,
The seismic isolation device according to claim 7.

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