JPH10205166A - Antiseismic structure for building - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antiseismic structure for a building, in which shocks generated when a ball runs through the center part of an inclined surface so as to enhance the effect of reducing acceleration transmitted to the structure upon earthquake and to prevent damage to the ball or a support member so as to enhance the durability. SOLUTION: An antiseismic structure for a building, includes a rolling bearing means 6 intervening between a footing 2 and a building 4, for supporting the building 4 which is therefore movable in a horizontal direction. The rolling bearing means 6 is mainly composed of a lower support panel 8 secured to the footing 2 and having a substantially conical shape inclined surface 8a, and a ball 12 which rolls on the inclined surface 8a of the lower support panel 8 when the footing 2 and the building 4 are horizontally moved, relative to each other. The center part of the inclined surface 8 is formed therein a spherical surface 8a1 having a radius greater than that of the ball 12, and the inclined surface has a straight line-like longitudinally sectional shape, outside of the spherical surface 8a1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a seismic isolation structure for a structure.

[0002]

2. Description of the Related Art In a seismic isolation structure of a structure, a vibration of the structure caused by an earthquake is interposed between a foundation and the structure by interposing a seismic isolation support that supports the structure movably in a horizontal direction. Reduced. Rolling bearings using balls and sliding bearings using sliding bodies are known as this seismic isolation support, and by using these seismic isolation supports such as rolling bearings in combination with spring means and damper means. The desired seismic isolation effect is obtained.

FIG. 3 shows an example of a conventional rolling bearing means. The rolling bearing means a includes a main body case c fixed to the base of the building b, a ball receiving seat d housed in the main body case c and having a spherical seat surface directed downward, and a ball receiving seat d. d, a large number of small-diameter balls e rotatably disposed around the ball e, and a ball receiving seat d via the large number of balls e.
And a large-diameter ball f rotatable on the seat surface. On the other hand, a support plate h for rolling the ball f on the upper surface during an earthquake is fixed to the foundation g.

The support plate h has a substantially circular shape in plan view.
Further, it has a substantially mortar-shaped slope h1 approaching the bottom of the building b as going outward from the center. Accordingly, the ball f is normally positioned at the lowest center portion of the support plate h, and the ball f attempts to return to the center position of the support plate h during an earthquake, so that a restoring force required for seismic isolation is obtained.

According to the rolling bearing means a, when an earthquake occurs and the building b and the foundation g are relatively displaced in the horizontal direction,
The ball f rolls on the slope h1 of the support plate h while being held by the main body case c, and the building b is movably supported on the foundation g. Thereby, the effect of reducing the acceleration propagating to the building b during an earthquake is obtained.

[0006]

However, in the conventional rolling bearing means a, as shown in FIG. 4, the ball f rolls on the slope h1 and passes through the center of the slope h1, which is the lowest point. In this case, the vehicle crosses the center part in a form that collides with the uphill slope (point P) on the opposite side, which affects the effect of reducing the acceleration, damages the ball f and the support plate h, and generates a collision sound. There is also a risk of doing so.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and eliminates an impact when a ball passes through a central portion of a slope, thereby improving an effect of reducing an acceleration propagating to a structure. It is another object of the present invention to provide a seismic isolation structure for a structure capable of preventing damage to a ball and a support member, improving durability, and preventing occurrence of a collision sound.

[0008]

The present invention has the following configuration to achieve the above object. The invention according to claim 1 is a seismic isolation structure for a structure including a rolling support means interposed between a foundation and a structure to support the structure movably in a horizontal direction, wherein the rolling support means comprises: A support member fixed to a foundation or structure and having a substantially mortar-shaped slope, and a ball rolling on the slope of the support member when the foundation and the structure are relatively displaced in the horizontal direction. The center of the slope is a spherical surface having a radius larger than the radius of the ball, and the slope outside the spherical surface is formed to have a straight vertical cross section.

According to the first aspect of the present invention, the center of the slope is a spherical surface having a radius larger than the radius of the ball,
Since the slope outside the spherical surface is formed in a linear shape in the vertical section, the ball rolling on the slope is smoothly rolled on the spherical surface when passing through the center of the slope which is the lowest point. The transition from the down slope to the up slope does not impact the ball. Therefore, the effect of reducing the acceleration that propagates to the structure during an earthquake is improved, and there is no problem such as damage to the ball and the support member, so that the durability can be increased. In addition, it is possible to prevent occurrence of a collision sound.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. The seismic isolation structure according to the present embodiment is obtained by applying the present invention to a building for a general house.
As shown in FIG. 2, rolling support means 6 interposed between the foundation 2 and the building 4 to support the building 4 movably in the horizontal direction.
Is provided.

The rolling bearing means 6 is, as shown in FIG.
A lower support plate 8 fixed to the foundation 2, an upper support plate 10 fixed to the foundation of the building 4 opposite to the lower support plate 8, and between the upper support plate 10 and the lower support plate 8; A ball 12 is provided and rolls with respect to the upper support plate 10 and the lower support plate 8 when the foundation 2 and the building 4 are relatively displaced in the horizontal direction.

The upper support plate 10 has a lower surface 1 along a horizontal plane.
It is substantially circular in plan view having 0a. The lower support plate 8 has a substantially circular shape in a plan view, and has an upper surface formed with a generally mortar-shaped slope 8a approaching the upper support plate 10 from the center outward. Further, an annular flat portion 8b extending along a horizontal plane is formed on a portion of the upper surface outside the slope 8a, and the lower support plate 8 is fixed to the foundation 2 through the anchor bolt 14 in the flat portion 8b.

In this embodiment, as shown in FIG. 2, a spherical surface 8a1 having a radius R larger than the radius r of the ball 12 is provided at the center of the inclined surface 8a, and the spherical surface 8a1 is located outside the spherical surface 8a1. The slope is formed in a vertical section in a straight line. That is, a concave spherical surface 8a1 is formed in the range of the diameter D near the center, and the spherical surface 8a is formed.
In the range from the outer peripheral edge of 1 to the outer peripheral edge of the slope 8a, a frustoconical slope is formed smoothly and continuously with the spherical surface 8a1.

The ball 12 is usually located at the lowest center of the lower support plate 8 as shown in FIG. 1, and the center of the ball 12, the center of the upper support plate 10, and the center of the lower support plate 8 coincide. ing.

According to the present embodiment thus constructed, an earthquake occurs from the normal state shown in FIG.
When the base and the base 2 are relatively displaced in the horizontal direction, the ball 1
2 rolls on the slope 8a of the lower support plate 8 and the lower surface 10a of the upper support plate 10, respectively. At this time, the slope 8
Since the spherical surface 8a1 is formed on the a, the ball 12 rolling on the inclined surface 8a is smoothly rolled on the spherical surface 8a1 when passing through the center portion which is the lowest point, and moves from the downward inclined surface to the upward inclined surface. There is no impact due to the transition. Therefore, the effect of reducing the acceleration is improved, and there is no trouble such as damage to the ball 12 and the lower support plate 8, so that the durability can be increased. Further, the generation of collision noise can be prevented.

Since the slope 8a other than the spherical surface 8a1 has a straight vertical section, the ball 12 rolls mainly on the straight slope during an earthquake. Therefore, the restoring force of the ball 12 becomes constant without depending on the displacement of the ball 12 from the center portion, and therefore, there is no resonance point as in the spring mass point system.

This embodiment is a preferred embodiment of the present invention, and the technical scope of the present invention is not limited to this embodiment. For example, in the present embodiment, a mortar-shaped slope 8a
Is provided on the lower support plate 8, but the present invention is not limited to this, and a slope may be formed on the lower surface 10 a of the upper support plate 10. Further, in the present embodiment, the present invention is applied to the rolling bearing means 6 for rolling the ball 12 on both the upper support plate 10 and the lower support plate 8, but the present invention is not limited to this, and the present invention is not limited to this. Rolling bearing means (for example, a so-called free-bearing type bearing means) in which a ball is rotatably held on one of the objects and a supporting member is provided only on the other, and the ball is rolled only by the other supporting member. 3)) is also applicable. In addition, the present invention is not limited to a general house, and can be applied to a floor seismic isolation device for buildings and the like, and a seismic isolation device for valuables and works of art.

[0018]

As described above, according to the present invention, since the ball smoothly passes through the center, no impact is applied to the ball. Therefore, the acceleration reduction effect is improved, the durability of the ball and the support member is eliminated without damage, and the generation of collision noise can be prevented.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a rolling bearing unit according to the present embodiment.

FIG. 2 is a sectional view of a peripheral structure of a spherical surface according to the embodiment.

FIG. 3 is a sectional view of a rolling bearing means according to a conventional example.

FIG. 4 is a cross-sectional view of a peripheral structure around a central portion of a slope according to a conventional example.

[Explanation of symbols]

 2 Foundation 4 Building (example of structure) 6 Rolling bearing means 8 Lower support plate (corresponding to support member) 8a Slope 8a1 Spherical surface 12 Ball r Ball radius R Radius of spherical surface

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Motoharu Yabashi 1-5-1, Kiba, Koto-ku, Tokyo Inside Fujikura Co., Ltd.

Claims (1)

[Claims] 1. A seismic isolation structure for a structure having rolling bearing means interposed between a foundation and a structure for movably supporting the structure in a horizontal direction, wherein the rolling bearing means comprises a foundation or A support member fixed to the structure and having a substantially mortar-shaped slope, mainly comprising a ball rolling on the slope of the support member when the foundation and the structure are relatively displaced in the horizontal direction, A seismic isolation structure for a structure, wherein a center portion of the slope is a spherical surface having a radius larger than a radius of a ball, and a slope outside the spherical surface is formed in a vertical straight line.