JPH11303455A - Mounting structure of base isolation device for light-weight steel frame structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To install a base isolation device for a light-weight steel frame structure easily among steel-framed columns constituting the upper structure of the light-weight steel frame structure and extended in the vertical direction and a foundation stably. SOLUTION: The mounting structure of the base isolation device for the light-weight steel frame structure has an upper flange plate 35 and a lower flange plate 36, which are fixed at upper-lower both end sections of the base isolation device 20 and in which outer circumferential sections are projected from the upper end section and lower end section of the base isolation device 20 in the horizontal direction respectively, and a mounting plate 23, which is fixed at the lower end section of a steel-framed column 22 and an outer circumferential section is projected from a lower end section in the horizontal direction. The mounting plate 23 and the upper flange plate 35 are fixed by first bolts 26 under the state, in which the mounting plate 23 and the upper flange plate 35 are superposed, while a foundation 30 and the lower flange plate 36 are fastened by second bolts 31 buried to the foundation 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lightweight steel structure which is mounted between a vertically extending steel column constituting an upper structure of a lightweight steel structure and a foundation provided corresponding to the steel structure. It belongs to the technical field related to the mounting structure of a seismic isolation device for goods.

[0002]

2. Description of the Related Art Conventionally, seismic isolation bearings in which rubber and steel plates are alternately laminated between a vertically extending steel column and a foundation constituting a superstructure of a large steel structure such as a building or an apartment. It is well known that rubber-type seismic isolation devices are provided to reduce the vibration of superstructures due to earthquakes. The upper end of this seismic isolation device is fixed to a steel column with bolts and the like, while the lower end is fixed to a dedicated foundation fixed to the ground with anchor bolts and the like corresponding to the steel column. .

[0003]

By the way, in recent years, a seismic isolation device has been applied to a lightweight steel structure such as a steel-framed private house or a small warehouse, so that the structure itself or an installation in the structure can be installed. It is required to prevent collapse.

[0004] However, in the above lightweight steel structure, since the steel column and the seismic isolation device are smaller than the large steel structure, the contact area of the seismic isolation device with the steel column and the foundation is reduced, and the seismic isolation device is stabilized. It will be difficult to install. Further, even if the seismic isolation device is to be mounted on the steel column and the foundation with bolts that can be easily mounted, the space for fixing the bolts is small, and it is difficult to mount the seismic isolation device easily and securely.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an easy and stable seismic isolation device for a lightweight steel structure by devising a mounting structure of the seismic isolation device. To be attached to

[0006]

In order to achieve the above object, according to the present invention, the seismic isolation device is fixed to both upper and lower ends, and the outer peripheral portions of the seismic isolation device protrude more horizontally than the upper and lower ends. An upper flange plate and a lower flange plate,
A mounting plate fixed to a lower end portion of the steel column and having an outer peripheral portion protruding in a horizontal direction from the lower end portion, wherein the mounting plate and the upper flange plate are fixed by first bolts, while the foundation and the lower flange are fixed. The plate was fixed with a second bolt embedded in the foundation.

More specifically, according to the first aspect of the present invention, a vertically extending steel column constituting an upper structure of a lightweight steel structure is attached to a foundation provided corresponding to the steel column. For the mounting structure of seismic isolation devices for lightweight steel structures.

An upper flange plate fixed to the upper end of the seismic isolation device and having an outer peripheral portion protruding in a horizontal direction from the upper end, and fixed to a lower end of the seismic isolator and lower than the lower end. A lower flange plate having an outer peripheral portion projecting horizontally, and a mounting plate fixed to a lower end portion of the steel column and having an outer peripheral portion projecting horizontally from the lower end portion, and the mounting plate and the upper flange plate; Are fixed by a first bolt in a state of being overlapped, and the base and the lower flange plate are fixed by a second bolt having a lower part embedded so that an upper part protrudes from an upper surface of the base with respect to the base. Shall be

With the above structure, even if the steel column and the seismic isolation device are small, the contact area of the seismic isolation device with the steel column and the foundation can be increased by providing the upper flange plate, the lower flange plate, and the mounting plate. It is possible to secure a space for fixing the bolts. For this reason,
The seismic isolation device can be securely and stably attached. On the other hand, since the seismic isolation device can be attached to the steel column and the foundation with bolts, no special tools or techniques are required, and the attachment can be easily performed. Also,
It is easy to fix the upper and lower flange plates to the seismic isolation device. Therefore, the seismic isolation device can be easily and stably attached to the lightweight steel building by the bolt.

According to a second aspect of the present invention, in the first aspect of the present invention, the seismic isolation device is characterized in that the horizontal swing of the upper structure is caused by the rotation of the ball or the sliding of the sliding member or the magnetic members repelling each other. It is configured to be made smaller by sliding and to attenuate the horizontal displacement of the upper structure by the deformation resistance of the elastic body.

According to the present invention, the shock in the horizontal direction is reduced by the horizontal slide caused by the rotation of the ball or the like, and the frictional resistance of the ball and the deformation resistance (restoring force) of the elastic body at this time acts as a damping force. . Therefore, the swing of the upper structure can be suppressed smoothly, and the upper structure can be returned to the position before the movement after the convergence of the earthquake. In addition, the seismic isolation bearing rubber type used in large buildings, etc., exhibits seismic isolation performance due to the shearing force and shear deformation of the laminated rubber layer, so the movement distance due to horizontal shaking In order to earn more, it is necessary to increase the height by increasing the number of stacked layers, and it is necessary to increase the diameter to increase the height and stably support the upper structure, and the device becomes larger However, in the seismic isolation device of the present invention, the height is substantially determined by the size of the ball, the sliding member, and the magnetic body, and it is sufficient that these can support a lightweight upper structure. And the planar size can be considerably smaller than that of the base-isolated bearing rubber type. Further, since the restoring force of the elastic body and the frictional force of the rollers and the like can be adjusted, the restoring force can be set to an optimum value according to the weight of the upper structure. Therefore, a compact and lightweight seismic isolation device optimal for a lightweight steel structure can be obtained.

According to a third aspect of the present invention, in the first or second aspect of the present invention, 3 to 16 first bolts surround the steel column and the seismic isolation device at the outer peripheral portions of the mounting plate and the upper flange plate. Provided at substantially equal intervals on the circumference,
It is assumed that ~ 16 second bolts are provided at substantially equal intervals on the same circumference surrounding the seismic isolation device on the outer peripheral portion of the lower flange plate. This makes it possible to securely and stably mount the seismic isolation device while minimizing the time and effort required for mounting the seismic isolation device.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 and 2 show a mounting structure of a seismic isolation device for a lightweight steel building according to an embodiment of the present invention, and a vertically extending steel column 22 and an upper column 21 constituting an upper structure 21 of the lightweight steel building. A seismic isolation device 20 having a substantially cylindrical cross section along the horizontal direction is mounted between a base 30 provided corresponding to the base 22.

The above-mentioned steel column 22 has an H-shaped cross section and is connected to an adjacent steel column (not shown) by a beam 24 extending in the horizontal direction. A circular mounting plate 23 whose outer peripheral portion protrudes in the horizontal direction from the lower end is fixed to the lower end of the steel column 22. A plurality of (preferably 3 to 16) bolt insertion holes 23 a and 23 for inserting respective first bolts 26 described later are provided in the outer peripheral portion of the mounting plate 23.
are formed on the same circumference surrounding the steel column 22 at substantially equal intervals.

The lower portions of a plurality (preferably 3 to 16) of second bolts 31 made of T bolts are embedded on the same base 30 at substantially equal intervals on the same circumference. The upper portions (tip portions) of the second bolts 31, 31,... Protrude from the upper surface.

At the upper end of the seismic isolation device 20, an upper flange plate 35 whose outer peripheral portion projects horizontally from the upper end and has substantially the same shape as the mounting plate 23 is fixed. A plurality of bolt insertion holes 35a, 35a,... Are formed on the outer peripheral portion of the mounting plate 23 so as to correspond to the respective bolt insertion holes 23a of the mounting plate 23 in the vertical direction. The upper flange plate 35 and the mounting plate 23 are fixed by the first bolts 26 in a state of being overlapped. That is, the mounting plate 23 and the upper flange plate 35 are
The first bolts 26 are inserted through the upper flange plate 35 from the lower side of the upper bolts 35a and 35a, and the nuts 27 are fixed to the distal ends of the first bolts 26 by tightening. The first bolts 26 are provided at substantially equal intervals on the same circumference surrounding the steel column 22 and the seismic isolation device 20 at the outer peripheral portions of the mounting plate 23 and the upper flange plate 35. Will be.

At the lower end of the seismic isolation device 20, a lower flange plate 36 whose outer peripheral portion projects horizontally from the lower end and has substantially the same shape as the upper flange plate 35 is fixed.
In the outer peripheral portion of the lower flange plate 36, the bolt insertion holes 3 through which the second bolts 31 embedded in the foundation 30 are inserted.
6a, 36a,... Are formed. The base 30 and the lower flange plate 36 are fixed by the respective second bolts 31 and the respective nuts 32 fastened to the end portions of the respective second bolts 31. Note that the second bolts 31 are provided at substantially equal intervals on the same circumference surrounding the seismic isolation device 20 on the outer peripheral portion of the lower flange plate 36.

The seismic isolation device 20 is shown in FIGS.
As shown in (1), the horizontal swing of the upper structure 21 is reduced by the rotation of the spherical roller 5 (ball) or the lateral slide caused by the sliding of the sliding member 7, and the horizontal displacement of the upper structure 21 is reduced by rubber. It is configured to be attenuated by the deformation resistance of the members 8, 18 (elastic body) and returned. Usually, the height of each seismic isolation device 20 is 20 to 60 mm.
The outer diameter is 100 to 300 mm, and the ratio of the outer diameter to the height is set to 2 to 10. Even in a small installation space allowed for a lightweight steel structure, the support stability and seismic isolation It is made to show performance.

More specifically, the first embodiment shown in FIG. 3A has a circular steel upper plate 1 on which the upper flange plate 35 is fixed on the upper surface and a lower flange plate 36 on the lower surface. And a circular steel lower plate 2 to which is fixed. The upper plate 1 and the lower plate 2 are composed of outer members 1a and 2a constituting an outer peripheral portion.
And inner members 1b and 2b constituting an inner peripheral portion. The outer and inner members 1a, 1b, 2a and 2b are firmly connected to each other at a step portion by screws or the like.

At the center of the lower surface of the inner member 1b of the upper plate 1, the upper end of a roller holder 6 having a circular concave roller holding portion 6a opening on the lower surface is fixedly mounted. In the roller holder 6a of the roller holder 6, one or more spherical rollers 5, 5,... Having the same diameter are rollably held. In the case of a plurality of rollers, a plurality of rollers 5, 5,... May be arranged at substantially equal intervals on the same circumference, and one roller 5 may be arranged at the center.

The outer peripheral portions of the upper plate 1 and the lower plate 2 are resiliently connected by a cylindrical rubber member 8. The rubber member 8 is extended so as to generate a restoring force for returning the upper plate 1 to the position before the movement when the upper plate 1 moves in any direction in the horizontal direction relative to the lower plate 2. Has become. The rubber member 8 is made of a rubber compound mainly composed of natural rubber or synthetic rubber, or a composite material in which either rubber compound is reinforced with fibers. The rubber member 8 also has thickness changing portions 8a, 8a near the upper and lower ends, which become thicker in a circular arc having a smoother thickness toward the opposite side from the center in the vertical direction. , 2 alleviate stress concentration when they relatively move in the horizontal direction. Further, inside the upper and lower end surfaces of the rubber member 8, bonding portions 8b, 8b having a horizontal surface and a vertical surface are formed, and the horizontal surface and the vertical surface are formed by the outer members 1a,
2a is adhered over the entire circumference. This allows the upper plate 1
The space between the lower plate 2 and the lower plate 2 is substantially closed.

The space between the upper plate 1 and the lower plate 2 covered with the rubber member 8 is filled with an attenuator 10 made of a liquid viscous material or a powdery or granular polymer material.

When the seismic isolation device 20 of the first embodiment is used, the upper plate 1 smoothly moves relative to the lower plate 2 due to the rolling of each roller 5 when an earthquake occurs, and the sudden vibration is extended to a longer period. Soften. That is, the horizontal swing of the upper structure 21 is reduced by the horizontal slide caused by the rotation of the roller 5. At this time, since the rubber member 8 is deformed and expanded, the rubber member 8 generates a restoring force for returning the upper plate 1 to the position before the movement due to the deformation resistance. This rubber member 8
The restoring force acts as a damping force together with the flow resistance force of the damping agent 10, and attenuates the horizontal displacement of the upper structure 21. As a result, it is possible to prevent horizontal movement of the upper structure 21 without moving the upper structure 21 up and down, thereby preventing the object installed inside the structure from falling down. Can be returned to the position.

In the seismic isolation device 20 of the first embodiment,
The space between the upper plate 1 and the lower plate 2 covered with the rubber member 8 was filled with the attenuating agent 10, but it is not always necessary, and the material and the surface roughness of each roller 5 make the roller holder 6 or the lower plate 2 (The same applies to the second and third embodiments described later).

Next, a seismic isolation device 20 according to a second embodiment shown in FIG. 3B will be described. In the second embodiment, the method of holding the rollers 15 and the arrangement of the rubber members 18 are described in the first embodiment. It is different from that of the form described above. That is,
The seismic isolation device 20 is provided with a circular steel first plate member 11 to which an upper flange plate 35 is fixed on an upper surface, and is provided opposite the lower side of the first plate member 11 and has a lower flange on a lower surface. The second circular plate member 12 made of the same circular steel to which the plate 36 is fixed.
And The first and second plate members 11, 12
Is formed by one member, and circular concave portions 11a and 12a are formed in the center of the opposing surface, respectively.

The second plate member 12 is attached or fixed to the second plate member 12 with adhesive or bolts so that the base end (lower end) of the cylindrical side plate 13 is disposed on the outer periphery of the second plate member 12. The side plate 13 extends toward the first plate member 11 and covers a space between the first and second plate members 11 and 12. At the tip (upper end) of the side plate 13, four roller holders 1 each having a hemispherically concave shape at substantially equal intervals in the circumferential direction are provided.
3a, 13a,... Are formed. In addition, the top end of the side plate 13 and the first plate member 11
A sealing member 19 that seals a gap between the first and second members is attached or fixed with an adhesive or bolts.
The space between the plate members 11 and 12 is substantially closed.

The four roller holders 13a, 13a,... At the upper end of the side plate 13 have four spherical rollers 15,
Are held so as to be rollable. The first plate member 11 is placed on the upper side of each roller 15, and each roller 15 horizontally moves the first plate member 11 to the second plate member 1.
2 and the first plate member 11 is moved in a horizontal direction relative to the second plate member 12 by rolling when an earthquake occurs.

The central portion of the second plate member 12 (the central portion inside the side plate 3) and the central portion of the first plate member 11 are:
They are elastically connected by a substantially cylindrical rubber member 18 as an elastic body. The upper and lower ends of the rubber member 18 are larger in diameter than the columnar portion, and are fitted and adhered to the concave portions 1a and 2a of the opposing surfaces of the first and second plate members 11 and 12, respectively. . The rubber member 18 is made of the same material as that of the first embodiment, and extends when the first plate member 11 moves horizontally relative to the second plate member 12 so that the first member 11 extends. A restoring force for returning the plate member 11 to the position before the movement is generated.

The space between the first and second plate members 11 and 12 covered by the side plate 13 and the seal member 19 is filled with an attenuator 10 made of the same material as that of the first embodiment. ing.

Therefore, the seismic isolation device 2 of the second embodiment
0, the first plate member 11 is smoothly moved in the horizontal direction with respect to the second plate member 12 by the respective rollers 5 at the time of the occurrence of an earthquake, as in the first embodiment. Can be suppressed, and the horizontal displacement of the upper structure 21 can be attenuated by the restoring force of the rubber member 18 and the flow resistance force of the damping agent 10.

In the seismic isolation device 20 of the second embodiment,
The lower flange 36 may be fixed to the first plate member 11 upside down, and the upper flange 35 may be fixed to the second plate member 12.

Next, the seismic isolation device 20 of the third embodiment shown in FIG. 3C will be described. In the third embodiment, each roller 5 in the seismic isolation device 20 of the first embodiment is used instead of each roller 5. The sliding member 7 is made of a resin having a high compressive strength and a self-lubricating property (for example, a fluororesin) or a lubricating resin having a low friction coefficient made of a solid lubricant or a reinforcing fiber. That is, a substantially cylindrical steel support column 3 projecting downward is provided at the center of the lower surface of the inner member 1b of the upper plate 1.
Is fixedly attached to the upper end with adhesive or bolts. Between the lower end of the support column 3 and the upper surface of the lower plate 2,
A sliding member 7 for supporting the upper plate 1 slidably in a horizontal direction relative to the lower plate 2 together with the support columns 3 is provided. The sliding member 7 has a disk shape having substantially the same diameter as the support column 3, and is concentrically attached and fixed to the lower end of the support column 3 with an adhesive or a bolt.

Therefore, the seismic isolation device 2 of the third embodiment
0, the upper plate 1
Can smoothly slide with respect to the lower plate 2 to suppress the swing of the upper structure 21.

A first magnet (magnetic body) is provided instead of the sliding member 7 in the seismic isolation device 20 of the third embodiment.
A second member that repels the inner member 2b of the lower plate 2 with its first magnet
The same seismic isolation effect as described above can also be obtained by supporting the upper plate 1 in a state in which it is half-floated with respect to the lower plate 2 and lifting and sliding the magnet when the earthquake occurs.

As in the case of the seismic isolation device 20 of the second embodiment, a sliding member or a first magnet (in the case of the first magnet, the first magnet is used instead of the rollers 15 at the upper end of the side plate 13). The plate member 11 may be a magnet that repels the first magnet).

Further, in the above embodiment, the mounting plate 23 fixed to the lower end of the steel column 22 is circular. However, the mounting plate 23 is not limited to this shape, and may be formed in a rectangular shape or another polygonal shape shown in FIG. Good. In addition, the upper flange plate 35 and the lower flange plate 36 fixed to the upper and lower ends of the seismic isolation device 20 may have any shape, similarly to the mounting plate 23.

[0037]

As described above, according to the first aspect of the present invention, the mounting structure of the seismic isolation device between the steel column and the foundation is fixed to the upper and lower ends of the seismic isolation device, and the outer peripheral portion is formed. An upper flange plate and a lower flange plate respectively protruding in the horizontal direction are provided, and the mounting plate fixed to the lower end portion of the steel column and having an outer peripheral portion protruding in the horizontal direction is overlapped with the upper flange plate and bolted, and the lower flange is fixed. By fixing the plate with bolts embedded in the foundation, even if the cross-sectional area of the steel column and the seismic isolation device is small, the contact area is increased by the upper and lower flange plates and the mounting plate, and Space can be secured. Therefore, the seismic isolation device can be easily and stably attached to the lightweight steel building by the bolt.

According to the second aspect of the present invention, the horizontal vibration of the upper structure can be reduced by the horizontal sliding of the ball or the sliding members or the sliding of the magnetic members repelling each other. The structure is designed so that the horizontal displacement of the structure is attenuated by the deformation resistance of the elastic body, eliminating the need for height unlike the rubber-laminated seismic isolation device, and making it a lightweight seismic isolation device for steel-framed buildings. It is possible to obtain a small and flat optimal shape.

According to the third aspect of the present invention, since the mounting plate and the upper flange plate can be fixed on the same circumference at substantially equal intervals by using 3 to 16 bolts, the seismic isolation device can be mounted. Work can be simplified, and reliable and stable mounting can be performed.

[Brief description of the drawings]

FIG. 1 is a side view of the vicinity of a seismic isolation device showing an attachment structure of a lightweight steel frame seismic isolation device according to an embodiment of the present invention.

FIG. 2 is a perspective view of the same part as FIG.

FIG. 3 is a sectional view showing a specific configuration of the seismic isolation device.

FIG. 4 is a view corresponding to FIG. 2, showing another example of the shape of the mounting plate.

[Explanation of symbols]

 Reference Signs List 20 seismic isolation device 21 upper structure 22 steel column 23 mounting plate 26 first bolt 30 foundation 31 second bolt 35 upper flange plate 36 lower flange plate

Claims (3)

[Claims] 1. A seismic isolation device for a lightweight steel building attached between a vertically extending steel column constituting an upper structure of the lightweight steel building and a foundation provided corresponding to the steel pillar. An upper flange plate fixed to an upper end of the seismic isolation device and having an outer peripheral portion projecting horizontally from the upper end, and fixed to a lower end of the seismic isolation device; A lower flange plate having an outer peripheral portion projecting horizontally, and a mounting plate fixed to a lower end portion of the steel column and having an outer peripheral portion projecting horizontally from the lower end portion. The mounting plate and the upper flange plate And the lower flange plate is fixed to the base by a second bolt having a lower part embedded so that an upper part protrudes from an upper surface of the base. For lightweight steel structures characterized by the following: Mounting structure of seismic equipment. 2. The mounting structure of a seismic isolation device for a lightweight steel building according to claim 1, wherein the seismic isolation device rotates a ball in a horizontal direction of an upper structure or a sliding member or a magnetic material that repels each other. A structure for mounting a lightweight seismic isolation device for a steel structure, characterized in that the structure is configured to be reduced by horizontal sliding caused by sliding between each other and to attenuate horizontal displacement of an upper structure by deformation resistance of an elastic body. . 3. The mounting structure for a seismic isolation device for a lightweight steel building according to claim 1, wherein 3 to 16 first bolts are provided on the outer periphery of the mounting plate and the upper flange plate. Are provided at substantially equal intervals on the same circumference surrounding the seismic device, and 3 to 16 second bolts are provided on the same circumference surrounding the seismic isolation device on the outer periphery of the lower flange plate. A mounting structure for a seismic isolation device for a lightweight steel structure, which is provided at substantially equal intervals.