JPS61294231A - Vibration energy absorbing device - Google Patents

Abstract

PURPOSE:To maintain an energy absorbing function for a long period of time by alternately stacking elastic/plastic plate members and reinforcing plate members which respectively have a satisfactory small ratio of thickness to each diameter, and joining and interposing same between two fixed plates. CONSTITUTION:Fixed plates 23, 24 are fixed to members 21, 22 in such a manner as to face each other, and discoidal elastic/plastic members 25 and discoidal reinforcing members 26 are alternately stacked and interposed between the fixed plates 23, 24. Every elastic/plastic member 25 and every reinforcing member 26, and every member and every fixed plate 23, 24 are joined to each other by brazing and joining. As the elastic/plastic members 25, for example, lead is used, and as the reinforcing members 26, for example, iron is used. Each of the members has a satisfactory small ratio of thickness to diameter.

Description

Detailed Description of the Invention (Technical Field of the Invention) The present invention relates to a vibration energy absorption device used for vibration isolation or seismic isolation of structures, and in particular to a vibration energy absorption device that uses plastic deformation of a material to absorb vibration energy. The present invention relates to an improvement in a vibration energy absorbing device.

[Technical background of the invention and its problems]

Conventionally, in order to prevent structures from being destroyed by seismic forces, various vibration energy absorbing devices have been inserted between, for example, the foundation and the structure body.

Such vibration energy absorption devices are classified based on the energy absorption mechanism: viscous type devices that utilize the viscosity of a fluid or viscoelastic body, and I type devices that utilize friction between materials.
l! It is broadly divided into the friction method and the plastic method, which utilizes plastic deformation of the material.

Among the above-mentioned vibration energy absorption devices, most of the ones that adopt the plastic method utilize plastic deformation of metal materials, and have the advantage of being simpler in structure and lower in price than those of other methods. It is equipped with Iron, lead, or a lead-based alloy is usually used as the elastoplastic member that directly absorbs energy. Among these materials, lead-based materials have particularly excellent plasticity and have sufficient tracking characteristics even in imaging involving large displacements.

By the way, conventional vibration energy absorbing devices that utilize the elastic-plastic properties of materials due to shear deformation generally do not.

It is constructed as shown in FIG. 5, FIG. 6, or FIG. 8. That is, in the structure shown in FIG. 5, fixing plates 3.4 are fixed to the members 1.2 of the two target structures in such a manner that they face each other, and between these fixing plates 3.4, for example, lead-based It has a structure in which an elastic-plastic member 5 made of a material processed into a cylindrical shape is inserted. Note that each fixed plate 3.4 and the elastic-plastic member 5 are joined by soldering or the like. Also.

In the case shown in FIG. 6, both ends of one elastic-plastic member 5 are fitted into recesses 6.7 formed in each fixing plate 3.4.

Through this fitting, the elastic-plastic member 5 and each fixing plate 3.4 are coupled together. Furthermore, in the structure shown in FIG. 8, an elastic support, for example, a rubber bearing 8, for supporting the member 2 with respect to the member 1 is interposed between the fixing plates 3.4, and the rubber bearing 8 extends in the axial direction. A through hole 9 is provided.

This through hole 9 accommodates an elastoplastic member 5 wound with a helical coil 10 having a rectangular cross section. Note that the rubber bearing 8 is made by laminating and bonding metal plates 11 and rubber plates 12 alternately.

In these vibration energy absorption devices, when a structure is photographed due to an earthquake or the like and a relative displacement occurs between one member 1 and 2, the elastic-plastic member 5 existing between one member 1 and 2 is forcibly displaced. receive. At this time, when the first elastic-plastic member 5 is plastically deformed,
An energy loss equal to the amount of work required for its plastic deformation occurs, resulting in absorption of the vibrational energy between the parts 1, 2.

The vibration response of the entire structure is reduced.

However, the conventional vibration energy absorbing device configured as described above has the following problems.

That is, in the case shown in FIGS. 5 and 6, when the elastic-plastic member 5 is repeatedly deformed in the lateral direction due to the relative displacement of one member 1.2 in the lateral direction in the drawing, the fixing plates 3, 4
Fixing plates 3, 4 due to local restraint between and elastic-plastic member 5
Due to the difference in bending and tensile conditions between the near part and the central part.

After a relatively small number of repetitions, the elastic-plastic member 5 assumes a shape in which the portion X near the fixed plate 3.4 is constricted and the central portion Y is bulged, as shown in FIG. For this reason.

The resistance force required for plastic deformation becomes smaller and the energy absorption capacity decreases. Then, there is a problem in that the elastic-plastic member 5 eventually breaks at the constriction part 1 and loses its function as an energy absorbing device.

On the other hand, in the case shown in FIG. 8, the spiral coil 10 is wound around the outer periphery of one elastoplastic member 5, so the problem described in FIG. 7 is less likely to occur. However, with such a structure, the elastoplastic member 5 is housed within the rubber bearing 8 that is the support material for the structure, making maintenance or replacement of the entire energy absorption device extremely troublesome. 1
There is a problem in that it is not possible to promptly respond to weakening of the earthquake resistance due to a decrease in the energy absorption performance of the elastic-plastic member 5. Namely.

When the elastic-plastic member 5 undergoes repeated plastic deformation due to several earthquakes or vibrations, the structure of the second elastic-plastic member 5 changes and the energy absorption capacity decreases. therefore.

Generally, the entire energy absorbing device must be inspected and replaced if its characteristics are below a predetermined value.

If such replacement is not performed, the required seismic resistance and reliability will not be obtained in the case of the first earthquake, which will seriously affect the safety of the structure. However, with the structure shown in FIG. 8, the entire energy absorbing device is located within the rubber bearing 8, making it impossible to easily inspect the characteristics of the energy absorbing device. For this reason, there was a high possibility that the timing of replacement would be incorrect. In addition, in order to restrain the radial deformation of the elastoplastic member 9 and allow shear deformation, a helical coil 10 with a rectangular cross section is wound around the outer periphery of the elastoplastic member 5. 1 member 1, 2
When the elastic-plastic member 5 is deformed by receiving a relative deformation force due to relative displacement between the coils, the helical coil 10 also undergoes relative deformation between the respective coils. In this case, since the helical coil 10 is continuous, a twisting force will act on the helical coil 10. As mentioned above, since the helical coil 10 is in charge of the radial deformation force of the elastic-plastic member 5, an excessive force including this force and the above-mentioned torsion force acts on the helical coil 10. As a result, there is a risk that the helical coil 10 may break.

If it breaks, there will be no restraining force against radial deformation, resulting in the same problem as in the devices shown in FIGS. 5 and 6.

[Purpose of the invention]

The present invention has been made in view of the above circumstances, and its purpose is to be able to maintain the energy absorption function of an elastic-plastic member used for energy absorption for a longer period of time, and to facilitate maintenance. It is an object of the present invention to provide a vibration energy absorbing device that is easy to inspect or replace.

(Summary of the Invention) According to the present invention, the first and second fixed plates are each supported by two members capable of relative displacement, and each is formed into a plate shape having a sufficiently small ratio of thickness to diameter. A vibration energy absorbing device is provided that includes a plurality of elastoplastic members that are alternately stacked and inserted between first and second fixed plates and a plurality of reinforcing members that have greater material strength and rigidity than the elastoplastic members. .

〔Effect of the invention〕

When a vibration force that causes relative displacement between two members is applied, such as during an earthquake, each elastoplastic member repeatedly undergoes plastic deformation according to the amount of relative displacement between the two members. Specifically, a force acts on each elastic-plastic member to form a constriction at both ends and a bulge in the center.However, in the present invention, the elastic-plastic member is formed into a plate-like material whose thickness is sufficiently small relative to its diameter. In addition, this elastoplastic member is sandwiched and joined by reinforcing plates with high material strength and rigidity, so each elastoplastic member has a large resistance to bending and tension, and has a strong resistance in the thickness direction. It exhibits a characteristic that it has a relatively small resistance force against shear deformation in the direction perpendicular to the thickness direction.For this reason, when a deformation force in the direction perpendicular to the thickness direction is applied, only shear deformation occurs, and the resistance force in the direction perpendicular to the thickness direction There is almost no occurrence of constrictions at both ends or a bulge in the center.In this way, it is possible to prevent constrictions from occurring at both ends of one elastic-plastic member.
Due to the generation of this constriction, the elastoplastic member can be prevented from breaking even after a small number of repetitions.

As a result, each elastic-plastic member can exhibit a good energy absorption function over a long period of time. Also.

Because it can be installed independently from other elements.

It becomes easy to inspect the current state and characteristics of the elastoplastic member after an earthquake, and as a result, it can also contribute to preventing mistakes in the timing of replacement. Furthermore, since it can be installed independently of other devices, such as load supporting devices such as rubber bearings, it can also contribute to facilitating device replacement.

(Example of the invention) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a partially cutaway side view showing an example in which an imaging energy absorbing device according to an embodiment of the present invention is actually installed between members 21 and 22 of two target structures. That is, in this energy absorbing device, fixing plates 23, 24 are fixed to one member 21, 22 so as to face each other with bolts (not shown), and an elastic-plastic member is formed in a disk shape between the fixing plates 23, 24. 25 and reinforcing members 26, which are also formed in a disk shape, are alternately stacked and inserted. and,
Each elastic-plastic member 25 and each reinforcing member 26 and each fixing plate 23, 24 are joined by, for example, soldering or the like.

In this embodiment, each elastic-plastic member 25 is made of lead and has a sufficiently small ratio of thickness to diameter. Further, in this embodiment, the reinforcing member 26 is made of iron which has a higher tensile strength than the lead constituting each elastic-plastic member 25, and which has a sufficiently small ratio of thickness to diameter. Note that 27 and 28 in Figure 9 indicate reinforcing plates.

With such a configuration, members 21.2 may be damaged due to earthquakes, etc.
If a relative displacement occurs between the two in the lateral direction in the figure.

Each elastic-plastic member 25 is repeatedly subjected to deformation as shown in FIG. Therefore, energy consumption necessary for plastic deformation occurs within each elastic-plastic member 25, and this energy consumption provides the function as a vibration energy absorbing device.

At this time, generally, each elastic-plastic member 25 tends to develop a constriction or a bulge due to repeated deformation. However, in this case, each elastic-plastic member 25 is formed into a plate shape with a sufficiently small ratio of thickness to diameter, and the elastic-plastic members 25 are sandwiched between reinforcing members 26. Each elastoplastic member 25 has one of the forces transmitted from between the reinforcing members 26, that is, the force that deforms one elastoplastic member 25.
It exhibits a large resistance to bending and tension, and is difficult to cause deformation other than shear deformation. For this reason.

Shear deformation of each elastic-plastic member 25 is performed smoothly.

As a result, the occurrence of constrictions and bulges in each elastic-plastic member 25 is suppressed. In this way, it is possible to prevent the occurrence of constrictions that are likely to occur particularly at both ends of the elastic-plastic member 25, thereby preventing the elastic-plastic member 25 from breaking with a small number of repetitions, and maintaining good energy absorption function over a long period of time. can be demonstrated.

Furthermore, when actually installing this energy absorbing device, it can be installed independently of other elements. Therefore, inspections, characteristic tests, etc. can be carried out promptly after the earthquake has subsided, which can also contribute to preventing mistakes in the timing of replacement. moreover.

Because it can be installed independently from other elements.

This can also contribute to facilitating exchange, and in the end, the above-mentioned effects can be achieved.

Note that the present invention is not limited to the embodiments described above, and can be modified in nine different ways. That is, if a large earthquake or the like occurs and the relative displacement between the members 21 and 22 becomes extremely large, each elastic-plastic member 25 may be displaced beyond the allowable displacement layer, and each elastic-plastic member 25 may be destroyed. . Such destruction could pose a serious danger to the structure. Therefore, some kind of countermeasure is required, but as a countermeasure, it may be constructed as shown in FIG. That is,
Projected peripheral walls 2 with different radii on the upper and lower surfaces of the peripheral edge of each reinforcing member 26
9, 30 are provided, and each reinforcing plate 27, 28 is also provided with a similar projecting peripheral wall. and.

Each reinforcing member 26 is aligned with the protruding direction of the corresponding projecting peripheral wall.
is interposed between the elastic-plastic members 25. In this way,
A state is formed in which the peripheral wall 30 of the reinforcing member located at the upper stage is fitted into the space surrounded by the peripheral wall 29 of the reinforcing member 26 located at the lower stage, and the space between the peripheral wall 30 and the peripheral wall 29 is formed. An annular gap 31 is formed therein. Now, assuming that this gap 31 is set to a value equal to the allowable displacement amount of each elastic-plastic member 25, if the displacement between the two members 21 and 22 attempts to exceed a certain value, as shown in FIG. The protruding circumferential wall 29 and the protruding circumferential wall 30 engage with each other to restrain their displacement. Therefore, destruction of each elastic-plastic member 25 can be prevented. Of course, this configuration may also be used. Further, the shape of the first elastic-plastic member 25 is not limited to a disk shape, but may be a square plate shape, and its diameter and thickness are 2.
The number of sheets is determined by the quality of the target structure, the rigidity of the structure, the required amount of energy absorption, and the plastic properties of the elastic-plastic member used. Of course.

Furthermore, the material forming the first elastic-plastic member is not limited to lead.

Lead-based alloys, iron, etc. can be used, and it is desirable that the reinforcing member has a material strength sufficiently greater than that of the elastoplastic member. Furthermore, although the above-mentioned embodiments do not specifically mention load supporting means, when using a load supporting mechanism such as a rubber bearing that contracts when supporting a load, including during vibration deformation, two
Should a means for absorbing shrinkage, such as an elastic mechanism, be interposed between one of the two fixed plates and the member on which it is supported?

A gap corresponding to the shrinkage may be provided.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway side view showing an example of a vibration energy absorbing device according to an embodiment of the present invention actually installed between two members, and Fig. 2 is a partially cutaway side view showing an example in which the vibration energy absorbing device according to an embodiment of the present invention is actually installed between two members. Fig. 3 is a side view with a partial cutaway showing an example when the vibration energy absorbing device according to another overwhelming aspect of the present invention is actually installed between two members. Figure 4 is a cross-sectional view when the device is performing a displacement restraint operation, Figures 5 and 6 are longitudinal cross-sectional views of conventional vibration energy absorbing devices, and Figure 7 explains the problems with the above conventional device. FIG. 8 is a longitudinal sectional view of yet another example of a conventional vibration energy absorbing device. 21.22... Member, 23.24... Fixed plate, 25
... Elastoplastic member, 26... Reinforcement member, 29.30.
...Protruding peripheral wall that functions as an engagement part that restricts displacement. Applicant's agent Patent attorney Takehiko Suzue 1m7

Claims (2)

[Claims] (1) It is for absorbing kinetic energy during relative motion between two members, and the first and second fixed plates each supported by each member have a sufficient ratio of thickness to diameter. The first and second parts are formed in a small plate shape.
A vibration energy absorbing device comprising: a plurality of elastoplastic members alternately laminated and inserted between fixed plates; and a plurality of reinforcing members having greater material strength and rigidity than the elastoplastic members. (2) The vibration energy absorbing device according to claim 1, wherein the elastic-plastic member is made of one selected from lead, a lead-based alloy, and iron.