JPS62188834A - Vibration damping supporter - Google Patents

Abstract

PURPOSE:To effectively attenuate propagation of the earthquake to an upper construction by engaging the convex spherical part on the upper face of a support element in the concave spherical part on the lower face of an upper platform to make sliding contact with each other and placing the convex spherical face on the lower face of the support element on the upper face of a lower flat platform to make rolling contact with each other. CONSTITUTION:A concave spherical face if formed on the lower face of an upper platform 1 and a support element 2 has on the an upper and a lower face thereof convex spherical parts A and B having the same center point O. The curvature radius R of the convex spherical part B is greater than the curvature radius (r) of said concave spherical part A. The convex spherical part A is engaged in the lower concave spherical part to make sliding contact therewith. The upper face C of a lower platform 3 is flat and the convex spheri cal part B of the support element 2 makes contact with said upper face C to slide thereon. The curvature radius (r) of the convex spherical part A is determined according to weight W and the kind of material using Herz's formu la.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention is directed to a system that is installed between a foundation that is a source of vibration, such as a foundation ground during an earthquake, and structures, important machines, etc. that do not want to transmit this vibration. , relates to a vibration damping support device for preventing vibrations of a foundation from being transmitted to these structures.

[Prior art]

Conventionally, vibration-damping bearing devices have two structures: (1) a structure in which a support with an elliptical curved surface is placed between flat upper and lower shoes, and (2) a spherical body is placed between upper and lower shoes with a curved surface. There are things that have a built-in structure. However, all of these systems have drawbacks such as the fact that during an earthquake, the fulcrum changes due to the displacement of the foundation and the upper shoe is lifted up, giving rise to vertical vibrations to the structure above.

[Purpose of the invention]

The present invention has been made in consideration of such circumstances, and an object of the present invention is to provide a vibration damping bearing device that can sufficiently prevent earthquake motion from being transmitted to a superstructure.

[Structure of the Invention] Therefore, the present invention provides an upper shoe having a concave spherical surface formed on the lower surface;
It consists of a support in which convex spherical surfaces with the same center are formed on both the upper and lower surfaces, and the radius of curvature of the convex spherical surface on the lower surface is larger than the radius of curvature of the convex spherical surface on the upper surface, and a lower shoe with a flat upper surface. The convex spherical surface of the upper surface of the support is fitted onto the concave spherical surface of the lower surface of the shoe so as to bring them into sliding contact, and the convex spherical surface of the lower surface of the support is brought into rolling contact with the upper surface of the lower shoe. The gist is the bearing device.

Hereinafter, the configuration of the present invention will be explained in detail with reference to the drawings.

FIG. 1 is an explanatory cross-sectional view showing an example of the source vibration support device of the present invention. In FIG. 1, l is an upper shoe, and a concave spherical surface is formed on the lower surface of the shoe. Kamikutsu 1 is a house,
It can be installed on the underside of structures that you want to deplete, such as buildings, various tanks, important machinery, etc.

Reference numeral 2 denotes a support, and convex spherical surfaces A and B with O as the center point (the centers are the same) are formed on both the upper and lower surfaces, respectively. The radius of curvature R of the convex spherical surface B is larger than the radius of curvature r of the convex spherical surface A. The convex spherical surface A fits into the concave spherical surface on the lower surface of the upper shoe l, and is in sliding contact with the concave spherical surface.

3 is the lower shoe. The upper surface C of this lower shoe 3 is flat. The convex spherical surface B of the support 2 is in contact with the upper surface C, and is in rolling contact. In addition, in FIG. 1, the rising portions 4 are provided on both sides of the lower shoe 3, but the rising portions 4 may be omitted.

The radius of curvature r forming the convex spherical surface A is generally determined by Hertz's formula depending on the load W and the material. Also,
The radius of curvature R forming the convex spherical surface B is determined as follows. That is, when the sliding friction coefficient μ of the convex spherical surface A is measured and determined, the sliding friction resistance force f becomes r = wxμ. On the other hand, force F acting on convex spherical surface B, for example, due to earthquake acceleration α
is F= (W/g)Xα (g is gravitational acceleration)
, so rXf=RXF. From these equations α
The relational expression /g=(rXμ)/R is established, and the seismic acceleration α
R is determined by determining . That is, the curvature iR of the convex spherical surface B is determined by the minimum seismic acceleration that can cause impairment.

Also, the length of the arc of the convex spherical surface B is determined as the maximum amplitude of the earthquake,
From this, determine the required arc length EC and determine the distance GE'' on the upper surface C of the lower shoe 3 that is equal to this arc length EG, then this distance GE' becomes the movable distance on the upper surface C of the convex spherical surface B. Therefore, a braking wall (side wall of the rising part 4) can be created at point E.The braking surface of the support 2 is located on the OE cotton line Dr and at right angles to this OE line from the 0 point, as shown in Figure 2. D2 on the drawn line. Fig. 2 is an explanatory diagram showing the operating situation of the source vibration support device of the present invention. In Fig. 2, the lower shoe 3 moves to the maximum due to an earthquake and causes a braking action. In this case, D2 is in contact with the lower surface of the upper shoe 1, and D1 is in contact with the braking wall at point E' of the lower shoe 3.

The materials of each of the upper shoe 1, the support 2, and the lower shoe 3 may be appropriately selected depending on the load W, and are, for example, rolled steel, forged steel, cast steel, alloy steel, etc.

Examples are shown below.

EXAMPLE The source vibration effect was evaluated using a source vibration support device having a shape not shown in FIG.

The results are shown in Table 1 below.

(Margins below this page) Note) (11 Minimum seismic acceleration 19.6 gal, 19.8 gal
1 corresponds to seismic intensity scale 3 (8.0 to 25 gal).

(2) The maximum allowable amplitude is the limit amplitude, and if a larger amplitude is required, R must be increased.

As is clear from Table 1 above, the relationship between the minimum seismic acceleration and R for which impairment is desired can be obtained.

Furthermore, the maximum seismic acceleration that can cause impairment can be dealt with by determining the arc length of the convex spherical surface B as the maximum displacement amplitude.

This shows that the vibration damping bearing device of the present invention has a large original vibration effect.

〔Effect of the invention〕

As explained above, since the vibration-reducing support device of the present invention includes an upper shoe, a support, and a lower shoe of a specific shape, the present invention can achieve the following effects.

■ At the minimum seismic acceleration, the bearing begins to roll, causing an impairment effect, and is impaired up to the maximum earthquake amplitude.

When the amplitude becomes abnormal, a braking action occurs, and it is possible to prevent the collapse of the upper structure.

■ The vibration displacement of the foundation is absorbed by the horizontal rolling of the support.

■ When the bearing rolls, the fulcrum of the upper structure does not change because the convex spherical surface A rotates due to sliding, and the convex spherical surface B
are in rolling contact and the point of contact, that is, the fulcrum is on a perpendicular line to the fulcrum of the convex spherical surface A, so it is possible to sufficiently prevent the upper structure from collapsing.

(2) Since the radius of curvature R of the convex spherical surface B is larger than the radius of curvature r of the convex spherical surface A, the force for rolling the support from the lower shoe side that is in contact with the convex spherical surface B may be small.

Note that by using this force, the radius of curvature R of the convex spherical surface B can be selected to determine the seismic acceleration that can be impaired. on the other hand,
The force of rolling the support from the upper shoe side due to the movement of the superstructure becomes large.

[Brief explanation of drawings]

FIG. 1 is an explanatory cross-sectional view showing an example of the vibration damping bearing device of the present invention, and FIG. 2 is an explanatory diagram showing the operating status of the vibration damping bearing device of the invention. 1... Upper shoe, 2... Support, 3... Lower shoe, 4...
Standing part.

Claims (1)

[Claims] An upper shoe with a concave spherical surface formed on the lower surface, a support in which convex spherical surfaces with the same center are formed on both the upper and lower surfaces, and the radius of curvature of the convex spherical surface on the lower surface is larger than the radius of curvature of the convex spherical surface on the upper surface, and the upper surface. a flat lower shoe, the convex spherical surface of the upper surface of the support is fitted onto the concave spherical surface of the lower surface of the upper shoe so as to make sliding contact, and the convex spherical surface of the lower surface of the support is fitted onto the upper surface of the lower shoe. A vibration damping bearing device that makes rolling contact.