JPH0449384A - Oscillation-proof device for lightweight structure - Google Patents

Abstract

PURPOSE:To lower a manufacturing and setting cost with simple composition by filling the central hole of an oscillation-proof device main-body with laminated elastic members having reinforcing plates between a pair of fitting plates and a specific static shearing elastic modulus, with the low elastic member of low hardness. CONSTITUTION:Reinforcing plates 2, and the elastic members 3 of the rubber or the like of the static shearing elastic modulus of about 2 - 20 kg/cm<2> are alternately laminated, and the elastic member layers 3 at both the end sections are firmly fitted on fitting plates 1, 1, and an oscillation attenuating hole (h) penetrating in the central axis direction is formed, and an oscillation-proof device main-body S is composed. Besides, the hole (h) is filled up with the low elastic member 4 of the low hardness of the rubber or the like of an elastic modulus equal to or lower than the half of the static shearing elastic modulus of the elastic members 3. As a result, when the elastic coefficient of the lower elastic member 4 is changed, then a compression spring constant is not almost changed and a shearing spring constant is changed, and regardless of the dimension of the hole (h), the ratio of the shearing spring constant to the compression spring constant can be easily set to be a proper value.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The invention of this application relates to a seismic isolation device, particularly to a seismic isolation device for lightweight buildings.

[Prior Art] Conventional seismic isolation devices for buildings consist of an isolator that is installed between the ground and the building and that supports the building and acts to absorb seismic waves, and a damper that dampens the vibrations of the building. It is configured. The isolator is usually made of a rubber body with a reinforcing plate embedded therein, and the damper is usually made of a copper rod, coil spring, oil damper, or the like.

WJ The isolators and dampers are manufactured as separate products, and when installed, the building is supported by an appropriate number of isolators, and a separate damper is installed between each isolator.

However, since the isolator and damper are installed separately, the installation work becomes complicated, and in the case of a light-weight building, the equipment becomes excessive and the cost becomes high.

Therefore, in order to solve the above-mentioned conventional problems, our company has developed a seismic isolation device equipped with holes for vibration damping that penetrate in the vertical direction.

In this type of rubber body, vibration energy applied to the rubber body is absorbed within the rubber body, and vibrations are attenuated to a greater extent than in conventional rubber bodies.

Therefore, unlike conventional seismic isolation devices, there is no need to separately provide a damper for damping, and the structure is simple.
This means that it can be manufactured and installed at low cost.

However, in designing an isolator, the optimal ratio of the shear spring constant to the compression spring constant (shear spring constant/compression spring constant) is about 1/1000; The above ratio changes greatly, making it difficult to obtain a seismic isolation device having an appropriate ratio [Problem to be solved by the invention] Therefore, in the invention of this application, the size of the vibration damping hole is Regardless of the above, it is an object of the present invention to provide a seismic isolation device for lightweight buildings in which the ratio of the shear spring constant to the compression spring constant can be easily set to an appropriate value.

[Means to solve problems]

The invention described in claim 1 of this application relates to a seismic isolation device for lightweight buildings, and the reinforcement plate (2) and the elastic member layer are alternately laminated between a pair of mounting plates (1) (1) to provide seismic isolation. The device constitutes the main body (S), and is provided with a vibration damping hole (h) that penetrates at least the reinforcing plate (2) and the elastic member layer, and the hole (h) is filled with a low-hardness, low-elasticity member. ing.

In the invention set forth in claim 2 of this application, regarding the invention set forth in claim 1, the static shear modulus of the low elastic member is less than half that of the elastic member constituting the main body (S) of the seismic isolation device. .

In the invention set forth in claim 3 of this application, regarding the invention set forth in claim 2, the static shear modulus of the elastic member constituting the main body (S) of the seismic isolation device is approximately 2 to 20 kg/cta2.

[Effect]

The invention of this application operates as follows.

In this seismic isolation device, the building is supported by the main body of the seismic isolation device (S) and a low elastic member filled in the vibration damping hole (h).

In the above supported state, an external force that causes the low elastic member to expand outward due to the weight of the building acts on the low elastic member, but this expansion is caused by the elastic member layer forming the main body (S) of the seismic isolation This will be prevented by the reinforcing plate (2). Since there is no change in the volume of the low elastic member, the amount of compression of the low elastic member in the vertical direction due to the weight of the building does not become large. That is, in this seismic isolation device, even if the material of the low-elasticity member is changed (changed to one with a different elastic modulus), the change in the compression spring constant can be suppressed.

Further, when an external force is applied in the horizontal direction due to an earthquake or the like, since the hole (h) is filled with a low elastic material, the deformation prevention force against horizontal deformation will not be large. In this seismic isolation device, the material of the low-elasticity member is changed (changed to one with a different elastic modulus).
The shear spring constant changes depending on the material.

As mentioned above, in the seismic isolation device of the invention of this application, when the material of the low elastic member is changed (changed to one with a different elastic modulus), the shear spring constant changes with almost no change in the compression spring constant. becomes.

[Example] Hereinafter, the structure of the invention of this application will be described with reference to drawings showing one example.

In this embodiment, as shown in FIGS. 1 and 2, reinforcing plates (2) and elastic member layers (3) are alternately laminated, and the elastic member layers (3) at both ends are The mounting plates (1) are fixed to each other, and a vibration damping hole (h) penetrating in the direction of the central axis is formed to form the main body (S) of the seismic isolation device.

As shown in FIGS. 1 and 2, the mounting plate (1) has a thick-walled annular shape and is made of rope material.

The reinforcing plate (2) is a thin annular plate made of steel, and as shown in the figure, is set to have the same outer diameter as the mounting plate (1).

The elastic member layer (3) is made of rubber or the like and has a thin annular shape, and as shown in the figure, has an outer diameter slightly larger than the mounting plate (1).

On the other hand, the diameter of the hole (h) is about 275 (usually 215 to 215) the diameter of the main body (S) of the seismic isolation device, as shown in Figure 1.
475 (often used) as 1. This hole (h) is filled with a low-hardness, low-elasticity member (4). Incidentally, as the low elasticity member (4), for example, polybutadiene rubber or the like can be employed.

As a result of the experiment, the static shear modulus of the elastic member constituting the main body (S) of the seismic isolation device was set to about 2 to 20 kg/cm2, and the static shear modulus of the low elastic member (4) was set to about 2 to 20 kg/cm2. It has been found that when the elastic member layer (3) constituting the main body (S) of the seismic device is less than half of that, it is easiest to manufacture and has a sufficient function as a seismic isolation device.

Since this seismic isolation device has the above-described configuration, when a building is placed on top of it, the state changes from the state shown in FIG. 3 to the state shown in FIG. 4 depending on the weight of the structure. That is, as shown in FIG.
When the structure (a) is placed, the above-mentioned low elastic member (
The outer circumferential surface of the elastic member layer (3) spreads outward, but this is prevented by the reinforcing plate (2) as shown in section A of the figure.
) to the extent that the inner circumferential surface of the hole is pushed in slightly. and,
Since the volume of the low elastic member (4) does not change, the amount of vertical compression of the low elastic member (4) due to the weight of the building does not become large. Therefore, in this seismic isolation device, even if the material of the low elastic member (4) is changed (changed to one with a different elastic modulus), the change in the compression spring constant can be suppressed.

Furthermore, as shown in Figure 5, when an external force acts in the horizontal direction due to an earthquake, etc., the hole (h) is filled with a low elastic member (4), so the horizontal deformation occurs. The deformation prevention force is not large. and,
In this seismic isolation device, the material of the low elastic member (4) is changed (
If the elastic modulus is changed to one with a different elastic modulus, the shear spring constant will change accordingly.

As described above, in the seismic isolation device of the invention of this application, when the material of the low-elastic member (4) is changed (changed to one with a different elastic modulus), the shear spring constant changes with almost no change in the compression spring constant. Therefore, it is possible to provide a lightweight building seismic isolation device in which the ratio of the shear spring constant to the compression spring constant can be easily set to an appropriate value.

On the other hand, as shown in FIG. 6, the filling portion of the low elastic member (4) may be only a portion consisting of the elastic member layer (3) and the reinforcing plate (2) that constitute the hole (h). In this case as well, it will have substantially the same actions and effects as those described above.

[Effects of the invention] Since the invention of this application has the above-described configuration, it has the following effects.

If the material of the low-elasticity member is changed (changed to one with a different elastic modulus), the shear spring constant will change with almost no change in the compression spring constant. Therefore, regardless of the size of the vibration damping holes, Therefore, it is possible to provide a lightweight building seismic isolation device in which the ratio of the shear spring constant to the compression spring constant can be easily set to an appropriate value.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the seismic isolation device according to the invention of this application. Figure 2 is a perspective view of the external appearance of the seismic isolation device. FIG. 3 and FIG. 4 are explanatory diagrams of main parts of the seismic isolation device. FIG. 5 is a diagram showing a state in which the seismic isolation device is deformed. FIG. 6 is a sectional view of a seismic isolation device according to another embodiment of the invention of this application.

Claims (1)

[Claims] 1. The main body (S) of the seismic isolation device is constructed by alternately laminating reinforcing plates (2) and elastic member layers between a pair of mounting plates (1) (1), and at least the reinforcing plates (2) A seismic isolation device for a lightweight building, characterized in that it is provided with a hole (h) for vibration damping that penetrates the elastic member layer, and the hole (h) is filled with a low-hardness, low-elasticity member. . 2. The static shear modulus of the low-elasticity member is based on the seismic isolation device (S
) is less than half of that of the elastic member constituting the structure. 3. A seismic isolation device for a lightweight building, characterized in that the static shear modulus of the elastic member constituting the main body (S) of the seismic isolation device is about 2 to 20 kg/cm^2.