JPH0660665B2 - Vibration energy absorber - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a vibration energy absorbing device used for vibration isolation or seismic isolation of a structure, and in particular, it absorbs vibration energy by utilizing plastic deformation of a material. The present invention relates to the improvement of the vibration energy absorbing device.

[Technical background of the invention and its problems]

Conventionally, in order to prevent the structure from being destroyed by seismic force, for example, various vibration energy absorbing devices are interposed between the foundation and the structure body.

Such vibration energy absorbing devices are classified according to the mechanism of energy absorption, viscous type using the viscosity of fluid or viscoelastic body, friction type using the friction of materials, and plastic type of materials. It is roughly classified into the plastic type utilizing deformation.

Of these, many of which adopt the plastic method utilize plastic deformation of a metal material, and have the advantages that the structure is simpler and the cost is lower than those of other methods. Lead, lead-based alloy materials, or iron materials are usually used as the elasto-plastic members that are directly used for energy absorption. In particular, lead-based materials have excellent plasticity and have sufficient tracking characteristics even with vibration accompanied by large displacement.

By the way, the conventional vibration energy absorbing device utilizing the elasto-plastic property due to the shear deformation of the material is generally configured as shown in FIGS. 10, 11 and 15. That is, as shown in FIG. 10, the end plates 3 and 4 are fixed to the members 1 and 2 of the two target structures so that they face each other. The structure is such that an elasto-plastic member 5 formed by processing the material into a cylindrical shape is interposed. The end plates 3 and 4 and the elasto-plastic member 5 are joined by brazing or the like. Further, in the structure shown in FIG. 11, the end plates 3 and 4 are provided with recesses 6 and 7 having the same diameter as that of the elastic-plastic member 5, and the both ends of the elastic-plastic member 5 are simply inserted and fitted into these recesses 6 and 7. The elasto-plastic member 5 and the respective end plates 3 and 4 are joined by joining or inserting and adhering. Further, in the structure shown in FIG. 15, an elastic support for supporting the member 2 with respect to the member 1, for example, a rubber bearing 8 is interposed between the end plates 3 and 4, and the rubber bearing 8 extends in the axial direction. A through hole 9 is provided,
An elastic-plastic member 5 wound with a spiral coil 10 having a rectangular cross section is accommodated in the through hole 9. The rubber bearing 8 is formed by alternately stacking metal plates 11 and rubber plates 12.

In these vibration energy absorbing devices, when a structure vibrates due to an earthquake or the like to cause relative displacement between the members 1 and 2, the elasto-plastic member 5 existing between the members 1 and 2 undergoes forced displacement. . When the elasto-plastic member 5 is plastically deformed, an energy loss equal to the amount of work required for the plastic deformation is generated. As a result, the vibration energy between the members 1 and 2 is absorbed, and 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, when the elasto-plastic member 5 is repeatedly deformed in the lateral direction due to an earthquake or the like, the joint surface between the elasto-plastic member 5 and the end plates 3 and 4 shown in P in FIG. There was a possibility of peeling. In the structure shown in FIG. 11, as shown by Q in FIG. 13, cracks are formed at the boundary R between the both ends of the elasto-plastic member 5 and the parts inserted into the recesses 6 and 7, and the joined state is obtained. There was a possibility that he would be released. When the joint surface is broken or cracked in this way, the state becomes the same as the break of the elasto-plastic member 5, and the function as the energy absorbing device is lost. Also, the elasto-plastic member 5 and the end plates 3, 4
Even if the joints with and are strengthened, in the case shown in FIGS. 10 and 11, when the elasto-plastic member 5 is repeatedly deformed in the lateral direction, the parts close to the end plates 3 and 4 and the central part are Due to the difference in the bending and tension states between the two, a constricted portion is formed in the portion X close to the end plates 3 and 4 and a bulging portion is formed in the central portion Y with a relatively small number of repetitions. For this reason, the resistance required for plastic deformation gradually decreases, and the energy absorption capacity decreases. Finally, there was a problem that the elasto-plastic member 5 was broken at the constricted portion and the function as the energy absorbing device was lost. On the other hand, in the structure shown in FIG. 15, the spiral coil 1 is attached to the outer periphery of the elasto-plastic member 5.
Since 0 is wound, there are few problems as described in FIG. However, with such a structure,
Since the elasto-plastic member 5 is housed in the rubber bearing 8 which is a support material for the structure, maintenance or replacement of the elasto-plastic member 5 becomes very troublesome and seismic resistance due to deterioration of energy absorption performance of the elasto-plastic member 5 is caused. There was a problem that we could not respond promptly to the weakening of sex. That is, when the elasto-plastic member 5 repeatedly undergoes plastic deformation due to several earthquakes or vibrations, the structure of the elasto-plastic member 5 changes and the energy absorption capacity decreases.
Therefore, in general, it is necessary to inspect the elasto-plastic member 5 and replace it if it has a predetermined characteristic or less. Without such replacement, the specified seismic resistance and reliability will not be obtained at the next earthquake, which will seriously affect the safety of the structure. However, in the structure shown in FIG. 15, since the elastoplastic member 5 is located inside the rubber bearing 8, the characteristics of the elastoplastic member 5 cannot be easily inspected. Therefore, there is a possibility that the replacement timing may be wrong. Further, in order to restrain the radial deformation of the elasto-plastic member 5 and allow the shear deformation, the spiral coil 10 is attached to the elasto-plastic member 5.
When the elasto-plastic member 5 is deformed by a relative deformation force due to the relative displacement between the members 1 and 2, the spiral coil 10 is also wound around the outer periphery of the spiral coil 10. Each coil undergoes relative deformation. In this case, since the spiral coil 10 is continuous, the spiral coil 1
Torsional force acts on 0. As described above, since the spiral coil 10 receives the radial deformation force of the elasto-plastic member 5, an excessive force, which is the sum of this force and the above-mentioned twisting force, eventually acts on the spiral coil 10. As a result, the spiral coil 10 may be broken. If it breaks, the restraining force against the radial deformation becomes small, and the same problems as those of the device shown in FIGS. 10 and 11 occur.

[Object of the Invention]

The present invention has been made in view of such circumstances, and an object thereof is to maintain the energy absorbing function of an elasto-plastic member provided for energy absorption for a longer period of time and to perform maintenance. Another object is to provide a vibration energy absorbing device that can be easily replaced.

[Outline of Invention]

According to the present invention, the first and second end plates are supported by the two members that move relative to each other at the time of an earthquake, and the both ends are inserted and joined into the recesses provided in the first and second end plates. In the vibration energy absorbing device provided with an elasto-plastic member having plasticity in the above-mentioned relation,
The first reinforcing member group embedded in the recess of the end plate over the recess of the second end plate, and at least the portion inserted into the recess in the elasto-plastic member and not inserted. There is provided a vibration energy absorbing device including a second reinforcing member group embedded across a boundary portion with the portion.

〔The invention's effect〕

When an oscillating force that causes relative displacement between two members is applied as in an earthquake, the elasto-plastic member repeats plastic deformation according to the amount of relative deformation between the two members. When subjected to such cyclic deformation, a force that causes a crack at the joint between the elasto-plastic member and each end plate, especially at the boundary between the portion inserted into the recess and the portion not inserted, is applied. To work. That is, a force that causes breakage acts at the joint between the elasto-plastic member and the end plate. However, since the first and second reinforcing member groups are embedded in the elasto-plastic member in the above relation, the strength of the above-mentioned boundary portion having the largest deformation strain in each part of the elasto-plastic member can be significantly strengthened, It is possible to prevent cracks and fractures from occurring in this portion. When the elasto-plastic member is repeatedly deformed, a force acts on the elasto-plastic member to form a constricted portion at both ends and a bulge portion at the center. However, since the first and second reinforcing member groups are embedded in the elasto-plastic member in the above relationship, the presence of these reinforcing member groups can prevent the occurrence of the constricted portion and the bulging portion. Therefore, it is possible to prevent the elasto-plastic member from breaking with a small number of repetitions due to the occurrence of the constriction.

In this way, the joint strength between the elasto-plastic member and the end plate can be greatly increased and the occurrence of a constriction in the elasto-plastic member can be prevented, so that a stable energy absorption function can be exhibited over a long period of time. be able to.

Further, since it is not necessary to dispose the elasto-plastic member in association with another device, the surface of the elasto-plastic member may be exposed or covered only with a cover or a rustproof film for preventing corrosion. it can. Therefore, it becomes easy to inspect the current state and characteristics of elasto-plastic members after the earthquake.
As a result, it is possible to contribute to incorrect exchange timing. Further, since it can be installed independently of other devices, for example, a load bearing device such as a rubber bearing, it can contribute to facilitating the replacement of the device.

Example of Invention

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows members 22 and 2 of two structures which are actually intended for a vibration energy absorbing device 21 according to an embodiment of the present invention.
It is a side view of the example installed in between 3.

This vibration energy absorbing device 21 is roughly divided into members 2
End plates 24 and 25 supported by bolts and the like (not shown) so as to face each other and end plates 24 and 2
5 and an energy absorber 26 inserted between the five.

As shown in FIG. 2, the end plates 24 and 25 are provided with recesses 27 formed by hollowing out the end plates 24 and 25. In the case of this embodiment, each of these recesses 27 is provided in the form of a through hole. Then, these recesses 27
Is a small-diameter portion 28 formed at a position opposite to the members 22 and 23, and a large-diameter portion that once spreads from the small-diameter portion 28 in a stepped shape and then gradually widens as it approaches the members 22 and 23. And 29.

On the other hand, the energy absorber 26 includes, for example, a lead-cylindrical elasto-plastic member 30 and a plurality of reinforcing member groups 31 a, 31 b, 31 embedded in the elasto-plastic member 30 in the axial direction.
It is composed of c and. The elasto-plastic member 30 is formed in a shape such that both ends thereof match the recesses 27 of the end plates 24 and 25,
The central portion is formed in a cylindrical shape having a diameter equal to the diameter of the small diameter portion 28. The both ends are the recesses 2 of the end plates 24, 25.
7 is inserted and joined. That is, this elasto-plastic member 3
0 is formed by casting with the inner surfaces of the recesses 27 of the end plates 24 and 25 as part of the mold surface. Then, the outer surface of the portion of the elasto-plastic member 30 inserted into each of the recesses 27 and the inner surface of the recess 27 are joined by fitting or brazing. The reinforcing member groups 31a, 31b, 31c
In the case of this embodiment, the reinforcing members 32, 33, and 34 constituting the above are iron having a higher tensile strength than the lead constituting the elasto-plastic member 30, and do not greatly affect the rigidity of the structure. In addition, the elasto-plastic member 30 having a thickness that can resist the radial deformation is used. Reinforcement member group 3
The reinforcing member 32 constituting 1a has the same length as the elasto-plastic member 30, that is, both ends are the recesses 27 of the end plates 24, 25.
It has such a length that it can be located inside, and as shown in FIG. 3 and FIG. 4, it is embedded in the elasto-plastic member 30 at a position closer to the outside at equal intervals in the circumferential direction. Further, the reinforcing member 33 forming the reinforcing member group 31b is formed to have a length about twice the thickness of the end plate 24, and the reinforcing member group 3
Inside the position where 1a is embedded, one end side is located in the recess 27 of the end plate 24 and the other end side is the end plate 2
It is located between Nos. 4 and 25, and is embedded at equal intervals in the circumferential direction as shown in FIG. The reinforcing member 34 that constitutes the reinforcing member group 31c is also formed to have a length that is about twice the thickness of the end plate 25, and one end side is located inside the position where the reinforcing member group 31a is embedded. The plate 25 is located in the recess 2 and the other end is located between the end plates 24 and 25, and is embedded at equal intervals in the circumferential direction as shown in FIG.

With such a structure, the members 22 and 2 are damaged due to an earthquake or the like.
When a relative displacement in the lateral direction in FIG. 1 occurs in 3, the elasto-plastic member 30 is repeatedly deformed as shown in FIG. Therefore, energy consumption necessary for plastic deformation occurs in the elasto-plastic member 30, and the energy consumption causes the function as a vibration energy absorbing device to be exerted.

In this case, when the elasto-plastic member 30 is repeatedly deformed, a crack is generated at the joint between the elasto-plastic member 30 and the end plates 24, 25, especially at the boundary R with the recess 27 at both ends of the elasto-plastic member 30. Such a force acts. However, the elastic-plastic member 30
At the boundary portion R between the portion inserted into the recess 27 of each end plate 24, 25 and the portion not inserted at both end portions of the end plate 24, the reinforcing member groups 31a, 31 are arranged so as to cross the boundary portion R.
b and 31c are embedded. Therefore, the strength of the boundary portion R having the largest deformation strain can be made much larger than that of the conventional one, and as a result, the occurrence of cracks in the boundary portion R can be prevented. Further, even if a constricted portion or a bulged portion is generated in the elasto-plastic member 30 due to repeated deformation, this generated force is suppressed by the reinforcing member group 31a and the reinforcing member groups 31b, 31c embedded over the entire axial length. As a result, the occurrence of necked parts and bulging parts is also suppressed.
In this way, the mechanical strength of the joint between the elasto-plastic member 30 and each of the end plates 24, 25 can be greatly increased, and the constriction and the bulge can be prevented from occurring. Therefore, a stable energy absorption function can be exhibited. Further, with the above configuration, the elasto-plastic member 30
Need not be provided in association with other devices. Therefore, it is possible to expose the surface of the elasto-plastic member 30 or only cover the surface with a cover or a film for preventing corrosion. Therefore, after the earthquake, the elasto-plastic member 3
It becomes easy to inspect the current state and characteristics of 0, and as a result, it is possible to contribute to prevention of error in the timing of replacement.
Moreover, as described above, since it can be installed independently of other devices, for example, load bearing devices such as rubber bearings,
It can also contribute to facilitating the replacement of the device, and in the end, the above-mentioned effects can be exhibited.

It should be noted that the present invention is not limited to the above-described embodiments, but can be variously modified. For example, as shown in FIG. 6, inside the reinforcing member group 31a, each end plate 24, 25
The reinforcing member group 31d including the reinforcing member 35 having a length equal to the length connecting the central portions of the concave portions 27 is embedded, and both ends of the reinforcing member group 31d and the reinforcing member group 31a.
And the connecting members 36a and 36b,
You may make it perform the position holding function at the time of casting with 6a and 36b. In addition, as shown in FIG.
The reinforcing member groups 31b and 31c may be embedded on the outer side of 1a. In addition, as shown in FIG.
Reinforcing members 32, 3 constituting 1a, 31b, 31c
You may make it curve 3 and 34 and embed it. Further, a plurality of annular reinforcing members that connect the reinforcing members of each reinforcing member group embedded in the axial direction in the circumferential direction may be embedded in the axial direction. Further, in the embodiment shown in FIG. 1, the end plates 24 and 25 are fixed to the members 22 and 23 with bolts or the like, but as shown in FIG.
The support recesses 41 and 42 are provided in the recesses 41 and 42, and the end plates 24 and 25 are fitted into the recesses 41 and 42 to such an extent that no resistance is generated in the axial direction, whereby the end plates 24 and 25 are restrained only in the relative movement direction. May be supported. With this configuration, even if the distance between the members 22 and 23 varies due to a load, for example, the axial compression or tensile load does not act on the energy absorbing device, so that the variation does not affect the energy absorbing characteristics. Can absorb minutes. Further, the shape of the elasto-plastic member is not limited to the cylindrical shape, and may be a prismatic shape, and the diameter and length thereof are the total number when the energy absorbing device is actually installed, the mass of the target structure, and the rigidity of the structure. ， Determined by the required energy absorption and the plastic characteristics of the elasto-plastic member used. Further, the material for forming the elasto-plastic member is not limited to lead, and lead-based alloys and iron can also be used.

[Brief description of drawings]

FIG. 1 is a side view of a vibration energy absorbing device according to an embodiment of the present invention when it is actually installed between two members, FIG. 2 is a longitudinal sectional view of the vibration energy absorbing device, and FIG. FIG. 4 is a view of the vibration energy absorbing device taken along the line AA in FIG. 1 and viewed in the direction of the arrow. FIG. 4 is a view of the vibration energy absorbing device cut along the line BB of FIG. 5 is a vertical sectional view when the vibration energy absorbing device is performing an energy absorbing operation, and FIG. 6 is a vertical sectional view of a vibration energy absorbing device according to another embodiment of the present invention.
7 and 8 are longitudinal sectional views showing a vibration energy absorbing device according to a further different embodiment of the present invention, respectively.
The figure is a view for explaining another example of the installation mode of the vibration energy absorbing device, and FIGS. 10 and 11 are vertical sectional views of the conventional vibration energy absorbing device, respectively, and FIGS.
FIG. 15 is a diagram for explaining the problems of the above conventional device,
The figure is a longitudinal sectional view of still another example of the conventional vibration energy absorbing device. 21 ... Vibration energy absorption device, 22, 23 ... Members that move relative to each other in the event of an earthquake, etc., 24, 25 ... End plates, 26 ...
Energy absorber, 27 ... Recess, 30 ... Elasto-plastic member,
31a, 31b, 31c, 31d ... Reinforcing member group, 3
2, 33, 34, 35 ... Reinforcing member.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Chiaki Tsuruya 413-4, Amama, Akigawa, Tokyo

Claims (4)

[Claims] 1. A first end plate and a second end plate for absorbing kinetic energy during relative movement between two members, the first and second end plates being supported by the respective members and having recesses respectively. , Both ends of which are inserted and joined to the recesses of the first and second end plates and are inserted between the first end plate and the second end plate, and have a plastic elastic-plastic member. A vibration energy absorbing device comprising: a first reinforcing member group embedded in the elasto-plastic member from a position inside the recess of the first end plate to a position inside the recess of the second end plate. And a second reinforcing member group embedded in the elasto-plastic member across at least a boundary between a portion inserted into the recess and a portion not inserted into the recess. Energy absorber. 2. The vibration energy absorbing device according to claim 1, wherein the elasto-plastic member is formed of one kind selected from lead, lead-based alloys and iron. 3. The first and second reinforcing member groups are each composed of a plurality of reinforcing members formed of a material having a material strength higher than that of the elasto-plastic member. The vibration energy absorbing device according to item 1. 4. The vibration energy according to claim 1, wherein the plurality of reinforcing members forming the first and second reinforcing member groups are arranged in the circumferential direction. Absorber.