JPH0660666B2 - 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 characteristic due to the shear deformation of the material is generally configured as shown in FIGS. 14, 15, and 19. That is, as shown in FIG. 14, the end plates 3 and 4 are fixed to the members 1 and 2 of the two target structures, respectively, 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, as shown in FIG. 15, the end plates 3 and 4 are provided with recesses 6 and 7 having the same diameter as 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. 19, 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 is changed as shown by P in FIG. There was a possibility of peeling. Also in the case shown in FIG. 15, the joint surfaces between the inner surfaces of the recesses 6 and 7 and the elasto-plastic member 5 are peeled off as shown by Q in FIG. There was a possibility that the bonded state might be released by coming out of the recesses 6 and 7. When the joint surface is ruptured or the joint state is released in this way, the elasto-plastic member 5 is in the same state as the rupture, and the function as the energy absorbing device is lost. Even if the joint between the elasto-plastic member 5 and the end plates 3 and 4 is strengthened, in the case shown in FIGS. 14 and 15, when the elasto-plastic member 5 is repeatedly deformed in the lateral direction,
Due to the difference in bending and tension between the parts near the end plates 3 and 4 and the central part,
As shown in the figure, the constricted part is at the part X near the end plates 3 and 4.
Further, a bulge portion is generated in the central portion Y. 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. 19, since the spiral upper coil 10 is wound around the outer circumference of the elasto-plastic member 5, 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 supporting member of the structure, maintenance or replacement of the elasto-plastic member 5 becomes very troublesome, and There is a problem that it is not possible to promptly deal with the weakening of the earthquake resistance due to the deterioration of the energy absorption performance of the plastic member 5. 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. 19, since the elasto-plastic member 5 is located inside the rubber bearing 8, the elasto-plastic member 5 is
The characteristics of can't be tested easily. 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 wound around the outer periphery of the elasto-plastic member 5. With such a structure, When the elasto-plastic member 5 is deformed by the relative displacement between the members 1 and 2, the helical coil 10 is also relatively deformed between the respective coils. In this case, since the spiral coil 10 is continuous, a twisting force acts on the spiral coil 10. 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 overheated. If it breaks, the restraining force against radial deformation becomes smaller.
Problems similar to those of the apparatus shown in FIGS. 4 and 15 will 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 relationship, at least a part of a portion of the elasto-plastic member which is inserted and joined to the recess is formed on the first and second ends of the elasto-plastic member. A vibration energy absorbing device which is formed to have a diameter larger than the diameter of the portion located between the plates, and which has a plurality of small-diameter reinforcing members embedded in the elasto-plastic member and having a material strength higher than that of the elasto-plastic member at least in the axial direction. Will be provided.

〔The invention's effect〕

When an oscillating force that causes relative deformation 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 repeated deformation in this manner, a force acts on the joint between the elasto-plastic member and each end plate so as to remove the jointed state or to facilitate the removal from the recess. That is, a force that causes breakage at the joint portion acts. However, since at least a part of the part that is inserted and joined to the recess at both ends of the elasto-plastic member is formed to have a larger diameter than the part located between the end plates, the joining area is much smaller than that of the conventional one. Can be widely used. As a result, the joint strength can be greatly enhanced and breakage can be prevented at this joint. When the elasto-plastic member is repeatedly deformed, the elasto-plastic member has constrictions at both ends.
A force that forms an expanded portion acts on the central portion. However, since the reinforcing member is embedded in the elasto-plastic member in the above relationship, the presence of the reinforcing member 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 diameter d formed at a position opposite to the members 22 and 23.
_It is composed of a small-diameter portion 28 and a large-diameter portion 29, which once expands in a stepwise manner from the small-diameter portion 28 and then gradually expands as it approaches the members 22 and 23.

On the other hand, the energy absorber 26 includes an elasto-plastic member 30 formed of, for example, lead in a cylindrical shape, and a plurality of reinforcing members 31 embedded in the elasto-plastic member 30 in the axial direction. Both ends of the elasto-plastic member 30 are formed in a shape matching the recesses 27 of the end plates 24, 25, and the central portion is formed in a cylindrical shape having a diameter d ₁ . And both ends are each end plate 2
It is inserted and joined to the recesses 27 of 4, 25. That is,
The elasto-plastic member 30 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 31 is
In the case of this embodiment, it is possible to resist the radial deformation of the elasto-plastic member 30 to the extent that it is iron having a higher tensile strength than lead constituting the elasto-plastic member 30 and does not significantly affect the rigidity of the structure. It has a thickness that can be used. These reinforcing members 31 have the same length as the elasto-plastic member 30, that is, the lengths at which both ends can be located in the recesses 27 of the end plates 24 and 25. As shown, they are embedded at equal intervals in the circumferential direction.

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, the joint portion between the elasto-plastic member 30 and the end plates 24, 25 is pulled out from the both ends 27 of the elasto-plastic member 30 or the force for peeling the joint portion. The force to exert it acts. However, both ends of the elasto-plastic member 30 are inserted into the recesses 27 of the end plates 24 and 25 and joined to the inner surface of the recess 27, and the recess 2
The diameter d ₂ of the portion located inside 7 is formed larger than the other portions. Therefore, the joint strength between the inner surface of the recess 27 and the both ends of the elasto-plastic member 30 can be made extremely large as compared with the conventional one, and as a result, peeling or disconnection at the joint,
That is, breakage at the joint can be prevented. Also,
Even if the elastic-plastic member 30 has a constricted portion or a bulged portion due to repeated deformation, the generated force is suppressed by the plurality of reinforcing members 31 embedded in the axial direction, and eventually the constricted portion or the bulged portion is generated. 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, it is not necessary to provide the elastoplastic member 30 in association with another device. 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, it becomes easy to inspect the current state and characteristics of the elasto-plastic member 30 after the end of the earthquake, and as a result, it is possible to contribute to the prevention of error in the replacement timing. Further, as described above, since it can be installed independently of other devices, for example, a load bearing device such as a rubber bearing, it can also contribute to facilitating the replacement of the device and, in the end, exhibit the effects described above. .

It should be noted that the present invention is not limited to the above-described embodiments, but can be variously modified. That is, in the above-mentioned embodiment, the recesses provided in the end plates 24, 25 have a through hole structure, but as shown in FIG. 6, they may have a bottomed hole structure recess 27a. Further, as shown in FIG. 7, a smooth curved surface portion 41 may be formed at the boundary between the portion inserted into the recess 27 and the portion exposed to the outside on the outer peripheral surface of the elasto-plastic member 30, or As shown in the drawing, a smooth curved surface portion 42 may be provided at the end of the small diameter portion 28 on the side opposite to the member, and as shown in FIG. 9, a step existing between the small diameter portion 28 and the large diameter portion 29. Parts may be omitted. Further, as shown in FIG. 10, the diameters of the large diameter portion 29a in the recess 27b may be made equal in the axial direction. Further, as shown in FIG. 11, annular members 43 for connecting the ends of the respective reinforcing members 31 in the circumferential direction are embedded in the portions located in the recesses 27 of the end plates 24, 25 at both ends of the elastic-plastic member 30. You may do it. Also, the 12th
As shown in the drawing, each reinforcing member 31 may be curved and embedded in the elastic-plastic member 30 so that the central portions thereof approach each other. Furthermore, the reinforcing member 3 embedded in the axial direction
A plurality of annular reinforcing members that connect 1 in the circumferential direction may be embedded in the axial direction. Further, in the embodiment shown in FIG. 1, the end plates 24, 25 are fixed to the members 22, 23 with bolts or the like, but as shown in FIG.
The support recesses 44 and 45 are provided in the respective recesses, and the end plates 24 and 25 are fitted into the recesses 44 and 45 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 changes due to a load or the like, the compression or tensile load acts on the energy absorbing device in the axial direction, so that the fluctuation does not affect the energy absorbing characteristics. Can absorb minutes. further,
The shape of the elasto-plastic member is not limited to a cylindrical shape and may be a prismatic shape. The diameter and length of the elastic absorption member are the total number when the energy absorber is actually installed, the mass of the target structure, the rigidity of the structure, Is determined by the amount of energy absorbed 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.
FIG. 7 to FIG. 11 are views for explaining a modified example, first.
FIG. 2 is a vertical cross-sectional view of a vibration energy absorbing device according to still another embodiment of the present invention, and FIG. 13 is a view for explaining another example of the installation form of the vibration energy absorbing device, FIGS. 14 and 15. FIG. 16 is a vertical sectional view of a conventional vibration energy absorbing device, FIGS. 16 to 18 are views for explaining the problems of the conventional device, and FIG. 19 is still another example of the conventional vibration energy absorbing device. FIG. 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, 27a ... Recess, 30 ... Elasto-plastic member, 31 ... Reinforcing member.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigeru Fujimoto 1 Komukai Toshiba-cho, Sachi-ku, Kawasaki-shi, Kanagawa Inside the Toshiba Research Institute Co., Ltd. (72) Inventor Noboru Narukawa Komukai-Toshiba, Kawasaki, Kanagawa No. 1 Incorporated company Toshiba Research Institute (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. In the vibration energy absorbing device provided, at least a portion of a portion of the elasto-plastic member inserted and joined to the recess is larger than a diameter of a portion of the elasto-plastic member located between the first and second end plates. The vibration energy absorbing device is characterized in that a plurality of reinforcing members each having a smaller diameter and having a material strength higher than that of the elastoplastic member are embedded in the elastoplastic member. 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 vibration energy absorbing device according to claim 1, wherein the plurality of reinforcing members embedded in the axial direction are arranged in the circumferential direction. 4. A portion of the elasto-plastic member which is inserted and joined to the recess is formed in a shape in which a diameter increases as the distance from the central portion of the elasto-plastic member increases. The vibration energy absorbing device according to item 1.