JP2013227769A - Base isolation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a base isolation device which can obtain a high base isolation effect with a simple structure.SOLUTION: A base isolation device includes: a lower member which is co-fastened to a foundation structure; an upper member which is co-fastened to a building body; an elastic body which is arranged under the upper member; and an intermediate member which is interposed between the elastic body and the lower member, has a plurality of steel balls, and includes a lower side support for supporting the steel balls from below and an upper side support for supporting the steel balls from above. The upper side support is formed with first recessed parts having a curvature radius approximately equal to or very slightly larger than that of the curved surface of the steel ball. The lower side support is formed with second recessed parts having a curvature radius larger than that of the curved surface of the steel ball and larger than that of the first recessed parts. The steel ball is mounted between the first recessed part and the second recessed part.

Description

  The present invention relates to a seismic isolation device.

  Since the Great East Japan Earthquake, earthquake countermeasures for building structures and civil structures have become urgent. Among them, it is installed between the foundation structure (support) fixed to the ground in buildings and bridges and the upper structure (supported body) to support the upper structure and reduce the input of seismic motion to the upper structure. Many proposals have been made regarding seismic isolation devices.

  For example, a rolling support structure using rolling elements has been proposed. This is fixed to the foundation and has a foundation-side plate having a base-side sphere housing part formed in a concave shape on the upper surface, and a concave shape fixed to the base that supports the house and arranged facing the base-side sphere housing part. A base-side plate having a base-side sphere housing portion formed, a steel sphere sandwiched between the base-side sphere housing portion and the base-side sphere housing portion, and supporting the base-side plate on the base-side plate, and an elastic member, A steel sphere is held at the approximate center of the base-side sphere housing portion and the base-side sphere housing portion (see, for example, Patent Document 1).

  In addition, it has been proposed that when an earthquake occurs, the steel balls roll between upper and lower flat plates, and the upper and lower flat plates move relative to each other in the horizontal direction to reduce the seismic motion input to the building. This is provided with a pair of upper and lower flat plates provided opposite to each other and fixed to the supported body and the support, a plurality of spheres interposed between the pair of flat plates, and a plurality of spheres between the pair of flat plates. And the annular member is disposed with a gap between one of the pair of flat plates, and the vertical load of the supported body is an upper flat plate, a plurality of spheres, And it is transmitted to a support body via a lower flat plate (see, for example, Patent Document 2).

JP 2005-264580 A JP 2006-241841 A

  However, there is concern about the occurrence of earthquakes greater than previously assumed seismic intensity, and there is a need for seismic isolation devices that can be applied to existing buildings as well as new buildings and that can provide a high seismic isolation effect.

  The problem to be solved by the present invention is to provide a seismic isolation device having a simple configuration and a high seismic isolation effect.

  In order to solve the above problems, a seismic isolation device according to the present invention includes a lower member fixed to a foundation structure by fastening, an upper member fixed to the building body by fastening, and a lower layer of the upper member. An elastic body arranged; a lower support body interposed between the elastic body and the lower member; having a plurality of steel spheres; supporting the steel sphere from below; and supporting the steel sphere from above An intermediate member having an upper support, and the upper support is formed with a first recess having a radius of curvature substantially equal to or slightly larger than the curved surface of the steel sphere, and the lower support has Forming a second recess having a curvature larger than the curved surface of the steel ball and greater than the curvature of the first recess, and mounting the steel ball between the first recess and the second recess It is characterized by that.

  In the seismic isolation device of the present invention, the upper member, the elastic body, and the intermediate member are fixed together.

  Moreover, the seismic isolation apparatus of this invention forms the L-shaped fastening part for fixing to a building main body on the surface at the side of the building main body of the said upper member, It is characterized by the above-mentioned.

  In the seismic isolation device of the present invention, the lower member and the lower support are formed with standing portions on the outer peripheral edge portions, and the second steel balls are formed on the opposing surfaces of the standing portions. A third recess, a fourth recess, and the third recess has a radius of curvature substantially equal to or slightly larger than the curved surface of the second steel ball, The concave portion is larger than the curved surface of the second steel sphere and has an elongated shape.

  The seismic isolation device of the present invention is characterized in that the lower member is formed with a flange for fixing to the foundation structure.

  Moreover, the seismic isolation device of the present invention is characterized in that an end of the standing portion of the lower support is formed in an L shape.

  The seismic isolation device of the present invention is characterized in that the elastic body is a vibration-proof synthetic rubber plate.

  In the seismic isolation device of the present invention, the lower member, the upper member, and the intermediate member are each made of a stainless steel plate, and the steel ball is made of stainless steel.

  According to the present invention, a high seismic isolation effect can be obtained with a simple configuration, and is particularly effective for seismic isolation of a detached building.

It is the figure which looked at the seismic isolation apparatus which concerns on embodiment of this invention from the top. FIG. 2 is a schematic cross-sectional view along the line AA in FIG. 1. It is a figure explaining operation | movement of a seismic isolation apparatus when a horizontal shake acts. It is a figure explaining operation | movement of a seismic isolation apparatus when the shaking of a vertical direction acts. It is the figure which looked at the seismic isolation apparatus which concerns on 2nd Embodiment from the top. It is explanatory drawing which shows the example of installation of a seismic isolation apparatus.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings, the same portions are denoted by the same reference numerals, and redundant description is omitted.

(First embodiment)
FIG. 1 is a top view of the seismic isolation device 100 according to the first embodiment of the present invention. 2 is a schematic cross-sectional view taken along the line AA in FIG.

  As shown in FIGS. 1 and 2, the seismic isolation device 100 according to the present embodiment is installed in a building such as a detached house, for example, and has a foundation structure fixed to the ground and above the foundation structure. It is installed between the supported building body.

  The seismic isolation device 100 is arranged in a lower member 1 fixed to a foundation structure (not shown) by fastening, an upper member 2 fixed to the building body (not shown) by fastening, and a lower layer of the upper member 2. An elastic body (anti-vibration rubber plate) 3 and an intermediate member 4 interposed between the elastic body (anti-vibration rubber plate) 3 and the lower member 1 are provided as main components.

  As shown in FIG. 2, the upper member 2, the elastic body (anti-vibration rubber plate) 3, and the intermediate member 4 are fixed together by, for example, screws 22. In FIG. 1, the screw 22 is not shown in order to avoid complication.

  An L-shaped fastening portion 21 is formed on the surface of the upper member 2 on the building side. As described above, for example, an elastic body (not shown) is interposed, and a bolt (not shown) is attached to the building body. Fixed.

  The lower member 1 is formed with a flange 12 and is fixed to the foundation structure with, for example, a bolt (not shown).

  As the lower member 1, the upper member 2, and the intermediate member 4, for example, a stainless steel plate is suitable.

  The elastic body 3 is preferably a vibration-proof rubber plate made of natural rubber or synthetic rubber, for example.

  The intermediate member 4 includes a plurality of steel spheres 5, a lower support 41 that supports the plurality of steel spheres 5 from below, and an upper support 42 that supports the plurality of steel spheres 5 from above. The upper support 42 is formed with a recess 42 a for accommodating the steel ball 5 on the surface facing the lower support 41. The recess 42 a is formed to have a radius of curvature that is substantially equal to or slightly larger than the curved surface of the steel ball 5. In a normal state, the steel ball body 5 is fitted into the recess 42a and holds its position.

  On the other hand, the lower support 41 is also formed with a recess 41 a for accommodating the steel ball 5 on the surface facing the upper support 42. The recess 41a is larger than the curved surface of the steel ball 5, and the curvature of the recess 41a is larger than the curvature of the recess 42a.

  The upper member 2 and the upper support 42 and the lower support 41 that are integrated by tightening are configured to be able to swing in the lateral direction (left and right in FIG. 2) with the steel ball 5 interposed therebetween. ing.

  The number of the steel spheres 5 is determined from the viewpoint of attenuation of the seismic energy, and is, for example, five as shown in FIG. If the number is too large, the processing of each member becomes complicated, which is not appropriate. If the number is too small, it is difficult to absorb seismic energy.

  The steel sphere 5 is preferably made of, for example, stainless steel, and it is preferable to apply grease or the like to the surface as a lubricant at the time of rocking, for example.

  A standing portion 11 is formed on the outer peripheral edge of the lower member 1. A standing portion 411 is also formed on the outer peripheral edge of the lower support 41.

  In the standing portion 11 of the lower member 1, a concave portion 11 a for accommodating the steel ball body 6 is formed on the surface of the lower support 41 that faces the standing portion 411. The concave portion 11a is formed to have a radius of curvature that is substantially equal to or slightly larger than the curved surface of the steel ball body 6. In a normal state, the steel ball body 6 is fitted into the recess 11a and holds its position.

  On the other hand, a recessed portion 411 a for accommodating the steel ball body 6 is also formed in the standing portion 411 of the lower support 41 on the surface facing the standing portion 11 of the lower member 1. The concave portion 411a is larger than the curved surface of the steel sphere 6 and has an elongated shape. A steel ball 6 is interposed between the recesses 11a and 411a.

  The lower member 1 and the lower support 41 are configured to be swingable in the vertical direction (vertical direction in FIG. 2) with the steel ball 6 interposed therebetween.

  The number of steel spheres 6 is determined from the viewpoint of attenuation of seismic energy. For example, as shown in FIG. 1 and FIG. If the number is too large, the processing of each member becomes complicated, which is not appropriate. If the number is too small, it is difficult to absorb seismic energy.

  The steel sphere 6 is preferably made of, for example, stainless steel, and it is preferable to apply grease or the like to the surface as a lubricant during swinging, for example.

  An end portion 411b of the standing portion 411 of the lower support body 41 is formed in an L shape. The L-shaped end portion 411b serves as a stopper for the upper member 2 that swings and rises more than usual during an earthquake.

  Next, the effect | action by the seismic isolation apparatus 100 comprised as mentioned above is demonstrated.

  FIG. 3 is a diagram for explaining the operation of the seismic isolation device 100 when a lateral vibration is applied to a building during an earthquake. In the seismic isolation device 100, since the upper member 2 and the upper support 42 are integrated together by tightening, the steel sphere 5 interposed between the lower support 41 and the lower support 41 in accordance with the lateral shaking is a recess. While rotating at 42a, it rolls on the curved surface of the recess 41a. Since the curved surface of the recess 41a is larger than the curvature of the steel ball 5, the steel ball 5 gradually rises while rolling along the curved surface of the recess 41a. As a result, the upper member 2 that competes more than usual collides with the end portion 411b of the standing portion 411 of the lower support 41. The impact at the time of the collision is reduced by the elastic body (anti-vibration rubber plate) 3.

  FIG. 4 is a diagram for explaining the operation of the seismic isolation device 100 when vertical shaking is applied to a building during an earthquake. In the seismic isolation device 100, the steel ball 6 interposed between the standing part 11 of the lower member 1 and the standing part 411 of the lower support 41 rotates in the recess 11 a with the vertical shaking. However, it rolls on the curved surface of the recess 411a. Since the curved surface of the recess 411a is larger than the curvature of the steel ball 6, the steel ball 6 gradually descends while rolling along the curved surface of the recess 411a.

  According to the present embodiment, the seismic energy acting on the building or the like in the event of an earthquake can be significantly attenuated, and a high seismic isolation effect can be obtained with a simple configuration, particularly effective for seismic isolation of a detached building. It is.

(Second Embodiment)
FIG. 5 is a view of the seismic isolation device 100a according to the second embodiment as viewed from above. The base isolation device 100a according to the second embodiment has the same basic configuration as the base isolation device 100 according to the first embodiment. On the surface of the upper member 2 on the building side, a flat plate-like fastening portion 23 is formed. For example, an elastic body (not shown) is interposed, and the upper member 2 is fixed to the building body with bolts (not shown).

  The seismic isolation device 100a thus formed is arranged as shown in FIG. 6, for example, and fixed to the foundation structure and the building body. The arrangement shown in FIG. 6 is an example, and the present invention is not limited to this. For example, when the seismic isolation devices 100 and 100a are installed at intervals of 2 m, according to the simulation, it is possible to attenuate the impact applied to the building during the earthquake by about 70%.

  According to this embodiment, since a fastening part is flat form, there exists an advantage that it is easy to arrange | position, without restricting to the four corners of a building main body.

  The embodiments of the present invention are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 ... Lower member 11 ... Standing part 2 ... Upper member 21 ... Fastening part 3 ... Elastic body 4 ... Intermediate member 41 ... Lower side support body 42 ... Upper side Support body 5, 6 ... Steel ball body 100, 100a ... Seismic isolation device

Claims (8)

A lower member fixed to the foundation structure by tightening;
An upper member fixed to the building body by fastening,
An elastic body disposed in a lower layer of the upper member;
An intermediate having a plurality of steel spheres interposed between the elastic body and the lower member, and having a lower support that supports the steel sphere from below and an upper support that supports the steel sphere from above With members,
The upper support is formed with a first recess having a radius of curvature substantially equal to or slightly larger than the curved surface of the steel sphere, and the lower support is larger than the curved surface of the steel sphere, A seismic isolation device, wherein a second concave portion having a curvature larger than a curvature of the first concave portion is formed, and the steel ball body is mounted between the first concave portion and the second concave portion.   The seismic isolation device according to claim 1, wherein the upper member, the elastic body, and the intermediate member are fixed together.   The seismic isolation device according to claim 1, wherein an L-shaped fastening portion for fixing to the building body is formed on a surface of the upper member on the building body side. On the outer peripheral edge of the lower member and the lower support, respectively, standing portions are formed,
On the facing surface of each of the standing portions, a third concave portion for accommodating the second steel ball body, a fourth concave portion are formed,
The third recess has a radius of curvature substantially equal to or slightly larger than the curved surface of the second steel sphere, and the fourth recess is larger than the curved surface of the second steel sphere and has an elongated shape. The seismic isolation device according to any one of claims 1 to 3, wherein the seismic isolation device is formed.   The seismic isolation device according to any one of claims 1 to 4, wherein the lower member is formed with a flange for fixing to the foundation structure.   The seismic isolation device according to claim 4, wherein an end of the standing portion of the lower support is formed in an L shape.   The seismic isolation device according to claim 1, wherein the elastic body is a vibration-proof synthetic rubber plate.   The said lower member, the said upper member, and the said intermediate member are respectively stainless steel steel plates, and the said steel ball body is stainless steel, The Claim 1 characterized by the above-mentioned. Seismic isolation device.

Images