JP2004278157A - Base isolating device, and base isolating structure of building - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a base isolating device and the base isolating structure of a building using the base isolating device suitable for a lightweight building and capable of attaining efficient base isolation with simple structure without making a large change in the usual construction process of the building. <P>SOLUTION: This base isolating device 1 is provided with a columnar elastic body 2 extending in a vertical direction, and a coil spring 3 built therein. A reinforcement AA with the lower end embedded and fixed in foundation concrete AC and with the upper end fixed to a sill AB is allowed to vertically pass through the elastic body 2 and the coil spring 3. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a seismic isolation device for seismic isolation of a building and a seismic isolation structure to which the device is applied.
[0002]
[Prior art]
Conventionally, as a seismic isolation device that absorbs vibrations caused by earthquakes and protects buildings, a structure in which steel sheets and seismic isolation rubber are alternately laminated has been applied to relatively high-rise and heavy buildings such as concrete buildings. However, they were extremely expensive and large, and were not suitable for low-rise, lightweight buildings such as wooden houses.
[0003]
Therefore, a seismic isolation device suitable for a wooden house or the like has been considered (for example, see Patent Document 1). This seismic isolation device has an elastic body made of a columnar rubber having a metal disk provided at an upper end and a lower end, a rod-like body embedded in a vertical posture inside the elastic body, and an upper part of the rod-like body. It is composed of a shaft screwed to the upper disk and fixed to the wooden base, and an anchor bolt screwed to the lower disk below the pest control and buried in the foundation concrete.
[0004]
[Patent Document 1]
JP-A-11-62309
[Non-patent document 1]
[0006]
[Problems to be solved by the invention]
However, the seismic isolation device having such a configuration can certainly be manufactured at a low cost with a simple configuration.However, since the rod-shaped body, the shaft body, and the anchor bolt are separated from each other, an earthquake-induced When the roll is extremely large, if the elastic body is not only elastically deformed obliquely but also ruptured, there is a possibility that the foundation concrete and the building structure above the base are separated and the building collapses. In addition, usually, at the time of foundation work at the time of construction of a building, a reinforcing bar (anchor) is erected after the foundation concrete is cast and before hardening, and the upper end of this reinforcing bar is fixed to a wooden base. Each of the divided rods, shafts and anchor bolts used in seismic isolation devices such as the above are different from ordinary rebars and are special ones. Instead, it is expensive.
[0007]
Accordingly, the present invention has been made in view of the above-described problems, and has been made in consideration of the above-described problems. It is an object of the present invention to provide a seismic device and a seismic isolation structure for a building using the device.
[0008]
[Means for Solving the Problems]
That is, the seismic isolation device of the present invention is attached to a foundation concrete of a building and a base arranged above the seismic isolation device to achieve seismic isolation of the building, and has a columnar elastic body extending in a vertical direction. And a coil spring built in the elastic body, and vertically penetrates a reinforcing bar having a lower end buried and fixed in the foundation concrete and an upper end fixed to the base through the elastic body and the coil spring. The feature is that it is.
[0009]
With such a seismic isolation device, the vibration received by the foundation concrete due to an earthquake or the like is first converted into the elastic deformation motion of the elastic body, and the deformation motion of the elastic body is converted into the expansion and contraction motion of the coil spring. It is possible to achieve effective seismic isolation without transmitting large shaking to the building structure. Also, since this seismic isolation device can be placed by inserting a reinforcing bar buried in the foundation concrete in an upright posture and fixed at the upper end to the base, there is no need to make major changes to the normal construction procedure, The arrangement work can be performed easily and in a short time.
[0010]
In particular, when the coil spring is arranged to be able to expand and contract in the vertical direction inside the elastic body, if the elastic body is distorted horizontally and obliquely in response to the roll, In order to accumulate force, the elastic body and the coil spring move to draw a figure of eight as a whole to achieve seismic isolation. Therefore, before the elastic body is deformed to the point where the elastic body is torn, the "eight-shaped" movement is immediately started in cooperation with the coil spring to absorb the shaking, and the building like the conventional product may collapse. Can be eliminated.
[0011]
Specifically, as the elastic body, it is preferable to use a synthetic rubber bush having a through hole formed at the center thereof so that the reinforcing bar can be inserted. In this case, an integral spring bush may be formed by the elastic body and the coil spring. Note that such a spring bush is applied to a wheel portion of an automobile, and the extension direction of a rubber elastic body having a columnar shape and the expansion and contraction direction of a coil spring are matched to apply an external force received by the wheel to the spring bush “8”. By converting the motion into a "?" Motion, the body sway is reduced, but the same effect is achieved in the spring bush according to the present invention.
[0012]
In addition, in order to realize a stable arrangement of the seismic isolation device with respect to the foundation concrete, the seismic isolation device is inserted into the upward hole opened on the top surface of the foundation concrete, and the reinforcing steel is inserted vertically and the elastic It is desirable to further provide a lower housing member that surrounds and houses the lower end. On the other hand, in order to realize a stable arrangement with respect to the base, this seismic isolation device is inserted into the downward hole opened on the lower surface of the base so that the rebar is inserted vertically, and the upper end of the elastic body is enclosed and housed. It is preferable to further provide an upper housing member.
[0013]
Furthermore, to reduce the frictional resistance by reducing the area of direct contact between the elastic body and the rebar, in order to ensure smooth elastic deformation of the elastic body, it is necessary to set the elasticity between the elastic body and the rebar inserted through it. It is preferable to further provide a guide member housed in the body and through which a reinforcing bar is inserted.
[0014]
The seismic isolation structure of the building of the present invention using the seismic isolation device as described above, the base concrete of the building, between the base placed above, between the columnar elastic body extending in the vertical direction and A seismic isolation device having a coil spring incorporated in the elastic body, and a lower end vertically embedded in the elastic body and the coil spring in the seismic isolator and fixed in the foundation concrete. This means that the reinforcing bar whose part is fixed to the base is penetrated. Therefore, an effective seismic isolation function can be provided at a low cost to a general house such as a relatively lightweight wooden building. Also, since there is no need to make a significant change to the construction procedure of the building, there is no need for a great deal of labor and time for construction. In particular, as the seismic isolation device of the seismic isolation device, a spring bush in which a coil spring is integrally incorporated in the elastic body made of a synthetic rubber bush and the extension direction of the elastic body matches the expansion and contraction direction of the coil spring is applied. It is desirable to do.
[0015]
In order to stably place the seismic isolation device in such a seismic isolation structure of a building, an upward hole that opens upward on the upper surface of the foundation concrete, while the lower end of the elastic body is formed at the lower end of the seismic isolation device. Providing a lower accommodating member material for surrounding and accommodating the portion, and inserting the lower accommodating member while inserting a reinforcing bar in the upward hole, or forming a downward hole that opens downward on the lower surface of the base, It is preferable that an upper accommodating member that surrounds and accommodates the upper end of the elastic body be provided at an upper end of the seismic isolation device, and a reinforcing bar be inserted into the downward hole and the upper accommodating member be inserted. Further, in order to realize smooth deformation of the elastic body, the seismic isolation device further includes a guide member housed in the elastic body and through which the reinforcing bar is inserted, between the elastic body and the reinforcing bar inserted through the elastic body. It is desirable to reduce the area of direct contact between the body and the rebar.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[0017]
This embodiment shows a seismic isolation device 1 applied to a relatively light wooden building such as a general house as an example. As shown in FIG. 1, this seismic isolation device 1 includes a plurality of reinforcing bars AA which are buried in a base concrete AC and a base AB made of a wooden prism, specifically, embedded in the base concrete AC and penetrate the base AB. Are intermittently arranged corresponding to the bar arrangement positions.
[0018]
The configuration of the seismic isolation device 1 will be specifically described. This seismic isolation device 1 includes an elastic body 2 serving as a main body of a seismic isolation function, a coil spring 3 built in the elastic body 2, and a lower housing member for stably disposing the elastic body 2 on a foundation concrete AC and a base AB. 4 and an upper housing member 5 and a guide member 6 for reducing frictional resistance between the elastic body 2 and the reinforcing bar AA.
[0019]
The elastic body 2 has a columnar shape with a diameter of about 10 to 12 cm and a height of about 15 cm or less having a through hole 21 extending in the vertical direction at the center, and is specifically a bush made of synthetic rubber. In addition, the diameter of the through hole 21 is slightly larger than the diameter of the reinforcing bar AA, and particularly, the diameters at the upper end and the lower end of the through hole 21 are further increased. The coil spring 3 is formed by spirally forming a metal wire, and may be a suitable one such as a pressing spring (compression spring) or a pulling spring. In the present embodiment, a straight type pressing spring is used. I have. The elastic body 2 and the coil spring 3 form an integral spring bush SB. This spring bush SB is provided in a predetermined formwork similarly to a spring bush used around a vehicle. After the spring 3 is arranged, a rubber material in a heated and molten state is injected, and the rubber is cooled and cured to be molded. The through-hole 21 is formed at the time of this molding.
[0020]
The lower housing member 4 is a plate-shaped member integrally having a disk-shaped horizontal wall 41 and a peripheral wall 42 standing up along the peripheral edge of the horizontal wall 41, and is formed by pressing or welding a metal plate. It was done. The diameter of the horizontal wall 41 is slightly larger than the diameter of the elastic body 2, and the inner circumference of the peripheral wall 42 is substantially equal to the diameter of the elastic body 2. In the center of the horizontal wall 41, a through hole 43 corresponding to the through hole 21 formed in the elastic body 2 is formed. On the other hand, the upper housing member 5 is obtained by turning the lower housing member 4 upside down, and includes a horizontal wall 51 and a peripheral wall 52 similarly to the lower housing member 4, and a through hole 53 is formed in the center of the horizontal wall 51. Is formed.
[0021]
The guide member 6 is formed of a small round pipe inserted into an upper end and a lower end of the through hole 21 of the elastic body 2 having a large diameter. , And the inner diameter substantially matches the diameter at the center of the through hole 21.
[0022]
With respect to the seismic isolation device 1 having such a configuration, the foundation concrete AC is a general solid foundation or cloth foundation, and includes a base concrete part AC1 and a rising concrete part AC2. In addition, the reinforcing concrete AA is intermittently buried in the upright posture in the foundation concrete AC so as to protrude upward from the upper surface of the rising concrete portion AC2. The upper end of the reinforcing bar AA is a screw shaft AA1. Then, a concave portion AC3 which is depressed in a circular shape in plan view is formed on the upper surface of the rising concrete portion AC2 around a plurality of reinforcing bars AA as appropriate. The inner diameter and the depth of the concave portion AC3 are such that the lower housing member 4 can just fit.
[0023]
The base AB is a general one that stands upright with the wooden prism laid down and is arranged along the concrete part AC2, and forms a through hole AB1 through which the upper end of the reinforcing bar AA is inserted. In addition, a concave portion AB2 is formed on the lower surface of the base AB, and the concave portion AB2 is formed in a circular shape and has a bottom surface centered on the through hole AB1. The inner diameter and the depth of the recess AB2 are such that the upper housing member 5 can be exactly accommodated.
[0024]
Then, the lower accommodating member 4 was inserted into the recess AC3 of the foundation concrete AC while inserting the reinforcing bar AA into the through hole 43, and the lower guide member 6 was inserted into the through hole 21 from above the lower accommodating member 4. The spring bush SB is accommodated. At that time, the reinforcing bar AA is inserted into the through hole 21 of the elastic body 2. Further, the upper guide member 6 is inserted into the through hole 21, and the upper housing member 5 is covered on the elastic body 2 while the reinforcing bar AA is inserted into the through hole 53 from above. Then, the reinforcing bar AA is inserted into the through hole AB of the base AB while maintaining the level, the base AB is placed on the upper surface of the upper housing member 5, and the reinforcing bar AA is tightened with the nut AD from above the base AB. Thus, the arrangement of the seismic isolation device 1 is completed, and the seismic isolation structure AX of the building is configured.
[0025]
In the building A to which the above-described seismic isolation device 1 is applied, when there is a roll due to an earthquake as shown by an arrow in FIG. 4A, the foundation concrete AC moves in the same direction as the ground shake. In response to the above, the elastic body 2 is elastically deformed and inclined and distorted in the direction opposite to the foundation concrete AC, but the coil spring 3 which extends obliquely with the deformation of the elastic body 2 deforms the elastic body 2 to its original shape. Use force to pull back to. Therefore, as shown in FIGS. 4A to 4F, the spring bush SB as a whole moves to draw the shape of the numeral “8” to absorb the vibration caused by the earthquake, and Swaying of the structure can be reduced to prevent damage and collapse. At this time, at the upper end and the lower end of the through hole 21 of the elastic body 2, the direct contact between the elastic body 2 and the reinforcing bar AA is prevented by the guide member 6, so that the entire spring bush SB operates smoothly. Is secured. Further, the spring bush SB is accommodated in the lower accommodating member 4 accommodated in the concave portion AC3 of the foundation concrete AC and the upper accommodating member 5 accommodated in the concave portion AB2 of the base AB, respectively, so that it is extremely stably arranged. Since the seismic isolation device 1 is entirely inserted through the reinforcing bar AA, the seismic isolation device 1 does not come off the foundation concrete AC or the base AB. And since such a seismic isolation device 1 and the seismic isolation structure AX have a simple configuration and do not significantly change the construction procedure in a conventional building, they can be provided at an extremely low price. The effective seismic isolation device 1 and the seismic isolation structure AX can be introduced into a light-weight wooden building such as a general house where it has been difficult to introduce the seismic isolation device because of price and size problems.
[0026]
Note that the seismic isolation device and the seismic isolation structure of the present invention are not limited to the above-described embodiment. For example, it is possible to apply other elastic materials such as hard urethane other than the rubber bush as the elastic body, or to change the shape of the elastic body to a square column or a polygonal column other than the column. Further, a tension spring or a conical pressing spring can be used as the coil spring. In addition, the specific configuration of each unit is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.
[0027]
【The invention's effect】
As described in detail above, the present invention uses two different elastic members, an elastic body and a coil spring incorporated therein, and inserts this between a foundation concrete and a base to insert a reinforcing bar therein. This is a seismic isolation device and a seismic isolation structure of a building to which it is applied. Therefore, effective seismic isolation can be achieved with a simple structure, and the seismic isolation of relatively lightweight wooden buildings, such as ordinary houses, which were difficult to apply until now, without making significant changes in the construction procedure. The introduction of a structure is possible.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view showing an embodiment of the present invention.
FIG. 2 is a side view of the same.
FIG. 3 is a sectional view taken along line II-II in FIG. 2;
FIG. 4 is an explanatory view showing the operation of the embodiment in a sectional view.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Seismic isolation device 2 ... Elastic body 3 ... Coil spring 4 ... Lower housing member 5 ... Upper housing member 6 ... Guide member AA ... Reinforcing bar AB ... Base AC ... Foundation concrete SB ... Spring bush

Claims (12)

It is attached to the foundation concrete of the building and the base placed above it, and aims at seismic isolation of the building,
An elastic body having a columnar elastic body extending in the vertical direction and a coil spring built in the elastic body, a reinforcing bar having a lower end buried and fixed in foundation concrete and an upper end fixed to a base, A seismic isolation device characterized by being vertically penetrated by a body and a coil spring. The seismic isolation device according to claim 1, wherein the coil spring is arranged so as to be able to expand and contract in the vertical direction. 3. The seismic isolation device according to claim 1, wherein the elastic body is a synthetic rubber bush having a through hole formed at a central portion thereof, through which the reinforcing bar can be inserted. 4. 4. The seismic isolation device according to claim 3, wherein the elastic body and the coil spring form an integral spring bush. 3. A lower housing member which is inserted into an upward hole formed in the upper surface of the foundation concrete to insert a reinforcing bar in a vertical direction and surrounds and houses a lower end portion of the elastic body. 5. The seismic isolation device according to 3 or 4. 3. An upper housing member which is inserted into a downward hole formed on the lower surface of the base to insert a reinforcing bar in a vertical direction and surrounds and houses an upper end portion of the elastic body. The seismic isolation device according to 3, 4, or 5. 7. The seismic isolation device according to claim 1, further comprising a guide member housed in the elastic body and through which the reinforcing bar is inserted, between the elastic body and the reinforcing bar inserted therethrough. A seismic isolation device including a vertically extending columnar elastic body and a coil spring built in the elastic body is disposed between a foundation concrete of a building and a base arranged above the foundation concrete. The seismic isolation of a building is characterized in that the lower end is vertically buried in the foundation concrete and fixed to the elastic body and the coil spring in this seismic isolation device, and a reinforcing bar whose upper end is fixed to the base is penetrated. Construction. 9. A spring bush in which a coil spring is integrally incorporated in the elastic body made of a synthetic rubber bush, and a direction in which the elastic body extends and a direction in which the coil spring expands and contracts is applied as the seismic isolation device. The seismic isolation structure of the listed building. An upward hole opening upward is formed on the upper surface of the foundation concrete, and a lower housing member for surrounding and housing the lower end of the elastic body is provided at the lower end of the seismic isolation device, and a reinforcing bar is inserted through the upward hole. The seismic isolation structure of a building according to claim 8 or 9, wherein the lower housing member is inserted. A downward hole opening downward is formed on the lower surface of the base, and an upper housing member that surrounds and houses the upper end of the elastic body is provided at the upper end of the seismic isolation device, and a reinforcing bar is inserted through the downward hole. The seismic isolation structure of a building according to claim 8, 9 or 10, wherein the upper housing member is inserted together with the upper housing member. 12. The building isolation system according to claim 8, 9, 10 or 11, wherein the seismic isolation device further includes a guide member housed in the elastic body and through which the reinforcing bar is inserted between the elastic body and the reinforcing bar inserted therethrough. Seismic structure.

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