JPH1193999A - Elasto-plastic damper and its maintenance method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To precisely estimate the period to perform a maintenance with a simple method by including one index connecting means for taking the broken state as the index for remaining life of the other connecting means. SOLUTION: When a piping system is vibrated to the wall surface of a building or a fixed structure by an earthquake, the relative displacement is transmitted to elasto-plastic members 6a, 6b through first and second connecting means 4, 5, and the elasto-plastic members 6a, 6b are elasto-plastically deformed to absorb the vibration energy of the piping system, whereby the vibration of the piping system is suppressed. Since the elasto-plastic members 6a, 6b have the property of being fatigue broken and ruptured when the elasto-plastic deformation is repeated, it is necessary to perform a maintenance before all the elasto-plastic members 6a, 6b are ruptured. In an elasto-plastic damper 3, all the elasto-plastic members 6 are replaced when the rupture of the index elasto- plastic member 6a is found, so that the maintenance time of the whole damper can be precisely estimated with a simple method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an elasto-plastic damper that absorbs vibration energy by utilizing elasto-plastic characteristics of an elasto-plastic member made of metal or the like, and a maintenance method thereof.

[0002]

2. Description of the Related Art Conventionally, in order to absorb vibration energy generated at the time of an earthquake or the like and suppress vibration, conventionally, elasto-plastic characteristics, visco-elastic characteristics, plastic flow characteristics, or friction between members of materials have been conventionally used. Various dampers utilizing such methods have been proposed.

[0003] Among them, the elasto-plastic damper utilizes the elasto-plastic characteristic of an elasto-plastic member made of metal or the like.
This elasto-plastic member is disposed between two members that are relatively displaced,
Vibration energy is absorbed by deforming according to the relative displacement. Known techniques relating to the elasto-plastic damper include, for example, JP-A-7-279777, JP-A-6-17557, and JP-A-5-93475.

First, JP-A-7-279777 and JP-A-6-17557 disclose that a single damper device is formed by combining two elasto-plastic dampers having different vibration absorption characteristics. A technical idea for appropriately adjusting the absorption characteristics is disclosed. JP-A-7-279
No. 477 discloses a structural member using two dampers, one elasto-plastic damper (lead damper) that yields with a low stress and the other elasto-plastic damper (plate-shaped steel damper) yielding with a higher stress. When the relative displacement of the steel damper occurs, the steel damper yields while the elastic damping of the lead damper occurs, and furthermore, the steel damper yields when a shear force exceeding the yield stress is applied, thereby causing a wide range of external forces from a low level to a high level. There is disclosed a concept for reducing the response to the problem. Japanese Patent Application Laid-Open No. Hei 6-17557 discloses a concept in which the same concept as described above is applied to a structural earthquake-resistant wall. That is,
One elasto-plastic damper yielding at low stress (low yield point steel plate) and the other elasto-plastic damper yielding at higher stress (high yield point steel plate) are joined side by side or overlapped on the same vertical plane Disclosed the concept of improving the durability and vibration damping properties of the earthquake-resistant wall by forming a steel earthquake-resistant wall for the structure by joining together and fixing the periphery of the steel earthquake-resistant wall to the steel frame of the structure. Have been.

On the other hand, JP-A-5-93475 discloses that
A technical idea for adjusting the vibration absorption characteristics of one elasto-plastic damper is disclosed. That is, one elasto-plastic damper is
Two base plates respectively connected to the two members which are relatively displaced, and a plurality of elasto-plastic members (energy absorbers) which are detachably mounted between these base plates.
And the shape of each elastic-plastic member,
The width of the plate at the center in the vertical direction is smaller than that at the end in the vertical direction. Then, the vibration absorption characteristics of the elasto-plastic damper are adjusted by appropriately adjusting the plate width at the center in the vertical direction of each elasto-plastic member and adjusting the rigidity of each elasto-plastic member.

[0006]

As described above, the elasto-plastic damper utilizes the elasto-plastic characteristics of an elasto-plastic member made of metal or the like. The plastic members are sequentially fractured by fatigue. Therefore, before the entire elasto-plastic damper is destroyed, maintenance such as replacing all elasto-plastic members of the elasto-plastic damper must be performed. At this time, for example, even when a plurality of elasto-plastic dampers are provided in the same structure, the fatigue state of the elasto-plastic member in each elasto-plastic damper differs depending on the mode and scale of vibration applied to each elasto-plastic damper. Also, the maintenance time is different for each elasto-plastic damper. Therefore, in order to eliminate unnecessary parts replacement and reduce costs, it is necessary to accurately estimate the maintenance time of each elasto-plastic damper.

[0007] However, Japanese Patent Application Laid-Open Nos. Hei 7-279777 and Hei 6-1 using two elasto-plastic dampers.
In the concept of JP-A No. 7557, no particular consideration is given to the estimation of the maintenance time of each elasto-plastic damper, and in order to estimate the maintenance time, the history of the elasto-plastic behavior of each elasto-plastic damper is measured by a displacement meter or the like. Therefore, it is inevitably a complicated method of constantly monitoring or measuring a crack or the like of the elasto-plastic member of each elasto-plastic damper. Also, Japanese Patent Application Laid-Open
In JP-A-93475, similar to the above, no particular consideration is given to the estimation of the maintenance time of the elasto-plastic damper. Although the concept of providing a difference in the rigidity of each elasto-plastic member is disclosed, there is no suggestion that the concept may be used for estimating the time when the elasto-plastic damper should be maintained.

An object of the present invention is to provide an elasto-plastic damper capable of accurately estimating a time to be maintained by a simple method and with high accuracy, and a maintenance method thereof.

[0009]

[Means for Solving the Problems]

(1) In order to achieve the above object, the present invention provides a first connecting means and a second connecting means which are respectively connected to two members which are displaced relative to each other, and the first connecting means and the second connecting means. A plurality of connecting means for connecting between means and elastically and plastically deforming in accordance with the relative displacement between the two members, wherein the plurality of connecting means are ruptured when fatigue fracture occurs. And the number of repetitions is smaller than that of the other connecting means, and includes at least one indicator connecting means for setting the broken state as an indicator of the remaining life of the other connecting means. When the two members are displaced relative to each other,
This relative displacement is transmitted to the plurality of connecting means via the first and second connecting means, and each of the plurality of connecting means undergoes elasto-plastic deformation. These plurality of connecting means are fatigue-ruptured and broken when elasto-plastic deformation is repeated a predetermined number of times, but in the present invention, the number of repetitions until breakage of the indicator connecting means is smaller than other connecting means. Is configured.
As a result, the index connecting means breaks down due to fatigue before the other connecting means, so that the other connecting means does not break at least until the index connecting means breaks. Therefore, whether or not the indicator connecting means has been broken can be used as an indicator of the remaining life of the other connecting means, and the remaining life can be estimated to estimate the time for maintenance. In this way, it is possible to estimate the time for maintenance of the entire elastic-plastic damper with a simple method and with high accuracy. Further, at this time, if the amount of energy that can be absorbed by the other connecting means after the breakage of the index connecting means is appropriately set in advance, it is possible to estimate the timing of maintenance with higher accuracy.

(2) In the above (1), preferably,
The indicator connecting means is configured such that when the two members are displaced relative to each other, the maximum stress generated by deformation corresponding to the displacement is greater than that of the other connecting means.
Generally, when a material having the same property undergoes elasto-plastic deformation, the greater the stress applied thereto, the smaller the number of repetitions until fracture in fatigue fracture. Therefore, by configuring the maximum stress generated in the indicator connecting means to be larger than that of the other connecting means, the number of repetitions until the indicator connecting means is broken can be made smaller than that of the other connecting means.

(3) In (1) above, preferably, the indicator connecting means has a rougher surface roughness than the other connecting means, a pre-deformation larger than the other connecting means, and the other connecting means. At least one of a lower yield force and a lower fatigue limit than said other coupling means. In general, the characteristics of a material having the same properties when it undergoes elasto-plastic deformation are represented by a single fatigue curve. As the stress applied to the material decreases, the number of repetitions until fracture in fatigue fracture increases. When the stress is reduced to some extent and the fatigue limit is reached, the number of repetitions up to the fracture becomes almost infinite, and the fracture is hardly caused by the finite number of elastic-plastic deformations. At this time, when the surface roughness of the material becomes rough, a predetermined amount of deformation is given to the material in advance, the yield force of the material becomes small, or the fatigue limit of the material becomes small, the fatigue curve becomes smaller. At least the portion before the fatigue limit is shifted to the low stress side. That is, in order to maintain the same number of repetitions until breakage, the applied stress must be reduced, and when the same stress is applied, the number of repetitions until breakage decreases. Therefore, by increasing the surface roughness of the connecting means for the indicator, increasing the amount of deformation given in advance, reducing the yield force, and reducing the fatigue limit than other connecting means, The number of repetitions until the connection means is broken can be smaller than that of other connection means.

(4) In order to achieve the above object, the present invention provides a first connecting means and a second connecting means which are respectively connected to two members which are displaced relative to each other, and the first connecting means. And a second connecting means, and a plurality of connecting means for performing elasto-plastic deformation in accordance with a relative displacement between the two members, wherein a part of the plurality of connecting means Only the connecting means is configured to be fractured by fatigue before the most other connecting means for a predetermined period.

(5) In order to further achieve the above object,
The present invention relates to a first connecting means and a second connecting means which are respectively connected to two members which are displaced relative to each other, and to connect between the first connecting means and the second connecting means,
A maintenance method for an elasto-plastic damper comprising a plurality of coupling means that undergoes elasto-plastic deformation in accordance with the relative displacement between the two members, wherein, of the plurality of coupling means, only a part of the The connection means is configured to be broken by fatigue failure only for a predetermined period of time before the connection means, and if a breakage of the part of the connection means is found, all of the connection means including most of the connection means which has not been broken Replace the connecting means.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. The embodiment described below is an embodiment of an elasto-plastic damper that supports a piping system of a power plant or a chemical plant. FIG. 1 shows a first embodiment of the present invention.
This will be described with reference to FIG. FIG. 2 is a schematic layout diagram illustrating an example of a piping system of a power plant, a chemical plant, or the like in which the elasto-plastic damper according to the present embodiment is arranged.

In FIG. 2, a piping system 1 for a predetermined process in a plant is routed.
Are supported on the wall surfaces of the building, fixed structures, and the like (both are not shown) via the supporting devices 2a to 2e.
At this time, these support devices 2a to 2e have a function of simply supporting the own weight of the piping system 1 or a function of restraining vibration by restraining the vibration of the piping during an earthquake or the like. And the layout of the piping system 1 in accordance with the layout and the like.

The piping system 1 is provided with the support devices 2a to 2e.
In addition, for example, in order to absorb vibration energy generated at the time of an earthquake or the like and to suppress vibration, it is supported by elastic-plastic dampers 3 and 3 against a wall surface or a fixed structure (not shown).

The present embodiment relates to the structure of the elastic-plastic damper 3. FIG. 1 is a perspective view showing the entire structure of the elasto-plastic damper 3 according to the present embodiment, FIG. 3 is a perspective view showing the detailed structure of an index elasto-plastic member 6a (described later) in FIG. 1, and FIG. FIG. 4 is a perspective view showing the detailed structure of (described later).
Shown in In FIG. 1, an elasto-plastic damper 3 according to the present embodiment includes two members that are relatively displaced from each other, in this case, joint connection members 7a and 7b (FIG. 2) fixed to the piping system 1 and the wall / fixed structure, respectively. ) Connected to the first connection means 4 and the second connection means 5 and connected between the first connection means 4 and the second connection means 5 so that the relative displacement between the two members can be reduced. And a plurality of connecting means 6 that undergo elasto-plastic deformation in response.

The first connecting means 4 includes a spherical joint 8, a length adjusting member 9, a fastening member 10, a connecting member 11, and a clearance member 1.
2, a connection member 13, and a break prevention member 14. The second connection means includes a spherical joint 15, a length adjustment member 16, a fastening member 18, a connection member 19, and a clearance member 2.
0, a connection member 21 and a break prevention member 22. The connecting means 6 includes an index elastic-plastic member 6a as an index connecting means and an elastic-plastic member 6b other than the index elastic-plastic member, and their respective shapes are as shown in FIGS. These elastic-plastic members 6a and 6b are made of the same material.

In the first connection means 4, the spherical joint 8
Is rotatably connected to a length adjusting member 9 whose axial length can be extended and contracted. A portion of the length adjusting member 9 opposite to the spherical joint 8 is connected to a plate-like portion 11 a of the connecting member 11. Fixed. Through holes (not shown) for passing the fastening members 10 are formed in the block-shaped portion 11b of the connection member 11, the three clearance members 12, and the block-shaped portion 13b of the opposite connection member 13, respectively. 3 and 4, through holes 6aa and 6ba for passing the fastening member 10 are formed in the upper portions of the elasto-plastic members 6a and 6b, respectively. These are, as shown in FIG. 1, a block-shaped portion 11b, an elasto-plastic member 6b, and a clearance member 1b.
2, the elasto-plastic member 6b, the clearance member 12, the index elasto-plastic member 6a, the clearance member 12, the elasto-plastic member 6b, and the fastening member 10,
10 skewers, and the fastening members 10 and 10 are firmly fixed to each other by being fastened.

On the other hand, the second connecting means 5 has substantially the same configuration as that of the first connecting means.
The spherical joint 15 is rotatably connected to the length adjusting member 16 fixed to the lower end of the elastic member 6a, 6b. Holes 6ab and 6bb are formed respectively, and the block-shaped portion 19b of the connecting member 19, the elasto-plastic member 6b, the clearance member 20, the index elasto-plastic member 6a, the clearance member 20, the elasto-plastic member 6b, the clearance member 20, the elasto-plastic The member 6b and the block-shaped portion 21b of the connecting member 13 on the opposite side are skewered by the fastening members 18 and 18 and are firmly fixed to each other.

In the first and second connecting means 4 and 5, the plate-like portions 13 a and 13 a of the connecting member 13 of the first connecting means 4 and the connecting member 19 of the second connecting means 5 are connected. Are formed with through holes (not shown) through which the break prevention member 14 penetrates, and the break prevention members 14 are passed through these through holes to form the plate portions 13a and 13a. The plate-shaped portion 19a is engaged. However, at this time, the size of the through hole of the plate portion 19a is larger than the diameter of the break prevention member 14,
Is formed between them. Thereby, when the relative displacement between the plate-shaped portion 19a and the plate-shaped portion 13a is smaller than the gap, the break prevention member 14 does not affect the relative displacement, but when the relative displacement is larger than the gap. The break prevention member 14 hits the edge of the through hole and limits the relative displacement. This is to ensure that the elasto-plastic damper 3 does not separate into two even if it is supposed that all the elasto-plastic members 6a and 6b break. Similarly, through-holes through which the break prevention member 22 penetrates also into the plate-like portions 21a of the connection member 21 of the second connection means 5 and the plate-like portion 11a of the connection member 11 of the first connection means 4 are provided. (Not shown) is formed,
These plate-like portions 21a, 21a are engaged with the plate-like portion 21b. With such a structure, roughly speaking,
While the upper member in FIG. 1 and the left member in FIG. 1 border on the constricted portions 6ac and 6bc of the elasto-plastic members 6a and 6b, vibrate with the piping system 1 connected via the joint connecting member 7a, Constricted portions 6ac, 6bc of elasto-plastic members 6a, 6b
The lower member in FIG. 1 and the right member in FIG.
It vibrates together with a wall surface, a fixed structure, and the like connected via the joint connection member 7b.

Here, the main part of this embodiment is that the index elasto-plastic member 6a, which is the index connecting means, has a larger number of repetitions until rupture at the time of fatigue failure than the elasto-plastic member 6b, which is another connecting means. That is, it is configured to reduce the number. That is, as can be seen by comparing FIGS. 3 and 4, the difference between the index elasto-plastic member 6a and the elasto-plastic member 6b is due to the relative displacement between the piping system 1 and the wall or fixed structure of the building. The only difference is that a hole 6ad is formed in the lower part of the constricted portion 6ac of the index elastic-plastic member 6a, which is the main part to be deformed. When the hole 6ad is formed, when the piping system 1 is relatively displaced by a certain amount between the piping system 1 and the wall / fixed structure, etc., the maximum stress generated in the index elastic-plastic member 6a by the deformation corresponding to the displacement is increased. And the maximum stress generated in the elastic-plastic member 6b. In addition,
The hole 6ad may or may not penetrate the index elastic-plastic member 6a.

Next, the operation and operation of the present embodiment having the above configuration will be described. When the piping system 1 vibrates with respect to a building wall or a fixed structure due to an earthquake or the like, the relative displacement of the piping system 1 is changed via the first and second connection means 4 and 5 to the elasto-plastic member 6.
a, 6b, the elasto-plastic members 6a, 6b undergo elasto-plastic deformation, respectively, and absorb the vibration energy of the piping system 1 to suppress the vibration of the piping system 1. However, these elasto-plastic members 6
Since a and 6b have the property of being fractured by fatigue when they undergo elastoplastic deformation a predetermined number of times, maintenance must be performed before all the elastoplastic members 6a and 6b break.

In general, when a material having the same properties undergoes elasto-plastic deformation, the stress applied thereto and the number of repetitions up to the fracture in fatigue fracture are represented by one fatigue curve. FIG. 5 shows a fatigue curve a for the material constituting the elasto-plastic members 6a and 6b. As shown in FIG. 5, as the stress σ applied to the material decreases, the number of repetitions n until fracture increases. Then, when the stress σ is reduced to some extent and reaches the fatigue limit, the number of repetitions n until the fracture becomes almost infinite, and the fracture is hardly caused by the finite number of elastic-plastic deformations.

Here, in the present embodiment, the holes 6ad are formed only in the index elasto-plastic member 6a as the index connecting means of the elasto-plastic members 6a and 6b, and the stress is concentrated, so that the same deformation condition is obtained. Even if there is, the index elastic-plastic member 6
The maximum stress σ _a1 (= the stress generated around the hole 6ad) is larger than the maximum stress σ _b1 of the other elasto-plastic member 6b. As a result, the number of repetitions n _a1 until fracture of the index elasto-plastic member 6a is equal to the number of repetitions n of the other elasto-plastic member 6b.
_Since it is less than _b1 , if the deformation history experienced by both is the same, the index elasto-plastic member 6a will necessarily fail and break before the other elasto-plastic members 6b. Therefore, at least until the index elasto-plastic member 6a breaks, the other elasto-plastic members 6b do not break, and at least the function of the elasto-plastic damper 3 is guaranteed until the index elasto-plastic member 6a breaks. Whether or not the index elastic-plastic member 6a has broken can be used as an index of the remaining life of the other elastic-plastic member 6b. Therefore, only monitoring whether or not the index elasto-plastic member 6a is broken is performed at all times. When the index elasto-plastic member 6a is found to be broken, the remaining life of the other elasto-plastic members 6b is not long and the time for maintenance should be long. Since it can be estimated that there is no elasto-plastic member 6b, all the elasto-plastic members 6 including the other elasto-plastic member 6b that has not been broken may be replaced. Here, the breakage of the index elasto-plastic member 6a at this time may be confirmed visually, but an electrical detection means may be used. FIG. 6 shows the detection by this electrical detection means. That is, as shown in FIG. 6, a conductive wire 2 deforming together with the index elasto-plastic member 6 a is provided on the side surface of the index elasto-plastic member 6 a.
3 is fixed, and the resistance of the conductor 23 is measured by the electric resistance measuring device 2.
Measure according to 4. At the same time that the index elastic-plastic member 6a breaks, the conductor 23 breaks, and the resistance measured by the electric resistance measuring device 24 becomes infinite. Thereby, the fracture of the index elastic-plastic member 6a can be confirmed even from a distant place.
Therefore, when the measured value of the electric resistance measuring device 24 indicates infinity, all the elasto-plastic members 6 may be replaced. Note that the conductor 23 and the electric resistance measuring device 24 are an example of a unit for detecting the breakage of the index elastic-plastic member 6a,
The breakage of the index elastic-plastic member 6a may be detected by using another electric detection unit or another non-electrical detection unit. In Japanese Unexamined Patent Publication No. Hei 5-93475, although no particular consideration is given to the estimation of the time at which the elasto-plastic damper should be maintained, the width of the central portion of each energy absorber in the vertical direction is appropriately adjusted to adjust each energy absorber. There is disclosed a configuration for adjusting the rigidity. Therefore, it is not impossible to consider a configuration in which this configuration is applied and the rigidity of one energy absorber is made smaller than that of the other energy absorber when the rigidity is adjusted. However, the stiffness and the yield point do not always correspond clearly, and the weakest stiffness does not always result in the first fatigue failure. Therefore, even with the configuration applied in this way, it cannot be used as an index for maintenance as in the present embodiment, and the above-described operation of the present embodiment cannot be obtained.

Here, by appropriately setting the shape and position of the hole 6ad of the index elasto-plastic member 6a, it is possible to more accurately estimate the time for maintenance. This will be described below. That is, in the present embodiment, the presence or absence of the hole 6ad causes stress concentration in the index elasto-plastic member 6a, thereby making the index elasto-plastic member 6a and the elasto-plastic member 6b different easily.
By appropriately setting the shape and position of the hole 6ad of the index elasto-plastic member 6a, the degree of stress concentration and the maximum stress value can be controlled to adjust the difference in rupture easiness. This means that by setting the hole 6ad, the fatigue state of the other elastoplastic member 6b when the index elastoplastic member 6a breaks can be set in advance. In other words, the index elastoplastic member 6a breaks. After this, the amount of vibration energy that can be absorbed by the elastic-plastic member 6b can be set in advance. Thus, only monitoring whether or not the index elasto-plastic member 6a has broken is performed, and when a rupture of the index elasto-plastic member 6a is found, the other elasto-plastic member 6b
Since the vibration energy that can be absorbed thereafter has already been clarified, the period until it is considered that disturbance exceeding the vibration energy is generated can be set as the remaining life of the other elasto-plastic member 6b. Therefore, the index elastic-plastic member 6a
It is possible to more accurately estimate the length of the period until the time when maintenance is required after the fracture.

Further, if the vibration energy to be set is set on the basis of the relationship with the cycle at which the fracture inspection is performed, more reasonable maintenance can be performed. This will be described below. That is, the amount of vibration energy that can be absorbed by the elasto-plastic member 6b after the rupture of the index elasto-plastic member 6a is larger than the maximum amount of vibration energy generated by a vibration disturbance such as an earthquake that can be considered in a cycle of performing the rupture inspection of the index elasto-plastic member 6a. Just set it. In this way, even if the index elasto-plastic member 6a breaks immediately after the previous inspection and remains in the broken state until the current inspection, the remaining elasto-plastic member 6b that has not broken remains the maximum Since the vibration energy can be absorbed, the function of the elasto-plastic damper 3 is maintained. Therefore, it is only necessary to check whether or not the index elasto-plastic member 6a is broken at each inspection cycle, and to replace all the elasto-plastic members 6a and 6b when a break is found. Function will always be maintained. Thereby, the index elastic-plastic member 6a
With the hole 6ad, it is possible to simultaneously control the inspection time and the maintenance time of the elasto-plastic damper 3.

As described above, according to the present embodiment, all elasto-plastic members 6 are replaced when a breakage of the index elasto-plastic member 6a is found. The maintenance time of the entire elasto-plastic damper 3 can be well estimated. Therefore, it is possible to eliminate unnecessary component replacement and reduce costs.

In the first embodiment, the stress concentration is generated by providing the hole 6ad in the index elastic-plastic member 6a. However, the present invention is not limited to such a structure. That is, the maximum stress generated in the index elasto-plastic member 6a is larger than the maximum stress generated in the elasto-plastic member 6b in the shape of the portion where the deformation corresponding to the relative displacement of the piping system 1 and the wall / fixed structure is generated. It suffices if it is configured as follows. Such modifications will be sequentially described below. (1) When Using Stress Concentration Due to Grooves or Recesses That is, as shown in FIGS. 7 and 8, not the hole 6ad but the groove 6ae or the groove 6af is formed in the narrow portion 6ac of the index elastic-plastic member 6a. Even with such a structure, stress concentration occurs in the groove 6ae or the groove 6af, and the maximum stress is larger than that of the other elasto-plastic member 6b. Therefore, the same effect as in the first embodiment is obtained. The grooves do not have to have a constant depth as shown in FIGS. 7 and 8 or have a linear shape, and may have a shape in which the depth is gradually increased or a curved shape. Also, in FIG.
ae is provided so as to cross the side surface of the constricted portion 6ac in the width direction, and in FIG. 8, the groove 6af is provided so as to cross the front surface of the constricted portion 6ac in the width direction. It is not limited to forming to
It may be provided only on a part of a certain surface (for example, in a cut shape of a predetermined length from one end surface). Further, the groove does not necessarily need to be formed in the constricted portion 6ac, and may be formed on any surface as long as the surface of the piping system 1, the wall surface, the fixed structure, and the like is deformed according to the relative displacement. . In these cases as well, the maximum stress is greater than without grooves,
A similar effect is obtained. Further, the grooves need not necessarily be formed. That is, even if the groove is not formed, the index elasto-plastic member 6a is deformed with respect to the concave portion where the stress concentration occurs.
May be smaller than the minimum curvature of a similar concave portion of the elasto-plastic member 6b. Also in these cases, the same effect is obtained because the maximum stress of the index elastic-plastic member 6a is larger than that of the index elastic-plastic member 6a.

(2) Method using inner / outer stress difference in bending deformation In other words, as shown in FIG. 9, an index elasto-plastic member 6aA having no holes or grooves as index connecting means (ie, FIG. The same elastic-plastic member 6b as that of FIG. 4) is used, and another elastic member 6bA that is slightly thicker than the elastic-plastic member 6b of FIG. 4 is used as another connecting means. The structure sandwiches the member 6bA. In this case, when bending deformation corresponding to the relative displacement of the piping system 1 and the wall surface / fixed structure, etc. occurs, the stress becomes larger on the outside of the member. The maximum stress of the member 6aA becomes larger than the maximum stress of the elasto-plastic member 6bA, and the index elasto-plastic member 6aA is quickly broken. Thereby, the same effect as in the first embodiment can be obtained.

In FIG. 9, the thickness of the elasto-plastic member 6bA is made larger than the thickness of the index elasto-plastic member 6aA in order to increase the difference between the maximum stresses. However, this is not always necessary. It may be thick.

The index elastic-plastic member 6aA as the index connecting means in FIG. 9 may be replaced by a thin film, for example, a metal plating. In this case, the following effects are obtained. That is, in the first embodiment and the like, the index elastic-plastic member 6 serving as the index connecting means is used.
Since a and 6aA constitute one support structure that provides rigidity to the entire elasto-plastic damper 3, after the index elasto-plastic member 6a breaks, the stiffness of the entire elasto-plastic damper 3 decreases accordingly. Therefore, at the time of initial design, the index elasto-plastic member 6a
It is necessary to calculate both the total stiffness before the rupture and the total stiffness after the rupture, and to study so that the vibration characteristics of the piping system 1 are not adversely affected even after the rupture. On the other hand, when the connecting means for index is a thin film, the rigidity of the entire elasto-plastic damper 3 is almost the same as before the fracture even if the fracture occurs, since the structure does not originally contribute to the rigidity.
The vibration characteristics of the piping system 1 after breakage do not change. Therefore, at the time of initial design, it is sufficient to calculate and study only the overall stiffness before the index elastic-plastic member 6a breaks, which facilitates the design.

(3) Others In addition to the above (1) and (2), there is a method of simply varying the thickness of the elasto-plastic member. That is, in this case, as the index connecting means, the index elasto-plastic member 6aA having no holes or grooves (that is, the elasto-plastic member 6b in FIG.
This is a method in which an elastic-plastic member 6bA slightly thicker than the elastic-plastic member 6b in FIG. 4 is used as another connecting means, and these are arranged as shown in FIG.

FIGS. 10 to 14 show a second embodiment of the present invention.
This will be described below. In the present embodiment, the fracture at the time of fatigue failure by shifting the fatigue curve between the index elastic-plastic member 206a as the index coupling means provided in the elastic-plastic damper and the elastic-plastic member 206b as the other coupling means is described. This is an embodiment in which the number of repetitions up to is different.

The index elastic-plastic member 2 which is a main part of the present embodiment
FIG. 10 is a perspective view showing the detailed structure of the 06a. In FIG. 10, the index elasto-plastic member 206a is substantially the same in material and appearance as the elasto-plastic member 6b as another connecting means in the first embodiment shown in FIG. That is,
On the upper part of the index elastic-plastic member 206a, the fastening members 10, 1
0 (see FIG. 1) through holes 206aa, 206
ba is formed, and fastening members 18, 18
Through holes 206ab, 206ab are formed to pass through, and a constricted portion 206ac is formed at the center in the vertical direction. However, at this time, the index elastic-plastic member 20
6a, a point in which a predetermined bending stress is applied in advance and deformed into, for example, a substantially square shape around the constricted portion 206ac, and then the bending stress is removed to return to the original shape. This is different from the elasto-plastic member 6b of the first embodiment. On the other hand, the elasto-plastic member 206b as another connecting means provided in the elasto-plastic damper of the present embodiment has exactly the same configuration as the elasto-plastic member 6b of the first embodiment, and is not deformed in advance. That is, thereby, the pre-deformation amount of the index elastic-plastic member 206a is made larger than the pre-deformation amount of the elastic-plastic member 206b.

The structure of the elasto-plastic damper according to the present embodiment other than the index elasto-plastic members 206a and 206b is as follows.
This is almost the same as the elasto-plastic damper 3 of the first embodiment.

As described above with reference to FIG. 5, in general, the characteristics when an identical material undergoes elasto-plastic deformation are represented by a single fatigue curve. The number of repetitions gradually increases. However, if the amount of deformation is previously given to the material, the larger the amount of deformation, the more the portion of the fatigue curve before the fatigue limit is shifted to a lower stress side. That is, in order to maintain the same number of repetitions until breakage, the applied stress must be reduced, and when the same stress is applied, the number of repetitions until breakage decreases. Here, in the present embodiment, since the pre-deformation amount of the elastic-plastic member 206b as another connecting means is 0, FIG.
As shown in FIG. 1, the fatigue curve B is the same as the fatigue curve A of the first embodiment (see FIG. 5), but the index elastic-plastic member 206a serving as the index connecting means is given a pre-deformation amount. Therefore, the fatigue curve C shifts downward from the fatigue curve B.

Accordingly, even if the maximum stress σ _a2 generated in the index elasto-plastic member 206a is equal to the maximum stress σ _b2 generated in the other elasto-plastic member 206b under the same deformation condition, the index elasto-plastic member Number of repetitions n until breakage of 206a
_{Since a2} is smaller than the number of repetitions n _b2 of the other elasto-plastic member 206b, the index elasto-plastic member 206a is larger than the other elasto-plastic member 206b if the deformation history experienced by both is the same as in the first embodiment. However, it also causes fatigue fracture and fracture first. Therefore, at least the index elastic-plastic member 206
Since the other elasto-plastic member 206b does not break until a breaks, the function of the elasto-plastic damper 3 is at least guaranteed until the index elasto-plastic member 206a breaks, and the index elasto-plastic member 206a is Whether the rupture has occurred can be used as an index of the remaining life of the other elastic-plastic member 206b. Therefore, as in the first embodiment, only monitoring whether or not the index elasto-plastic member 206a has broken is performed, and when a rupture of the index elasto-plastic member 206a is found, another elasto-plastic member 206b that has not broken is removed. All the elasto-plastic members 206 may be replaced.

That is, according to the present embodiment, the same effect as that of the first embodiment can be obtained.

In the first and second embodiments, the elasto-plastic members 6a, 6b and the like are substantially flat.
The present invention is not limited to this, and may be, for example, a member having a non-uniform thickness, a rod-shaped member, or the like.

It goes without saying that the first and second embodiments may be combined, for example, the index elasto-plastic member 6a shown in FIG. 3 may be deformed before being disposed.

Further, in the second embodiment,
The index elasto-plastic member 206a was given a predetermined amount of deformation in advance, while the elasto-plastic member 206b was not pre-deformed. However, the present invention is not limited thereto. You may make it smaller than the member 206a. In this case, a similar effect is obtained.

In the second embodiment, the fatigue curve is shifted downward by giving a deformation amount in advance. However, the present invention is not limited to this, and the fatigue curve can be shifted downward by other methods. Thus, a similar effect can be obtained. Such modifications will be sequentially described below.

(A) Method Utilizing Difference in Surface Roughness That is, the index elastic-plastic member 206 of the second embodiment is used.
a and the elasto-plastic member 206b are replaced with the index elasto-plastic member 3 having substantially the same outer diameter and relatively coarse surface roughness.
06a and an elasto-plastic member 306b having a relatively fine surface roughness
Is used. In this case, as the surface roughness increases, the fatigue curve shifts to a lower stress side as a whole. As shown in FIG. 12, the fatigue curve d of the index elasto-plastic member 306a is better than the fatigue curve of the elasto-plastic member 306b. It shifts below curve E. Accordingly, under the same deformation condition, the maximum stress σ generated in the index elastic-plastic member 306a
_{Even if a3} and the maximum stress σ _b3 generated in the other elastoplastic member 306b are equal, the number of repetitions n _a3 until the index elastoplastic member 306a breaks is the number of repetitions n of the other elastoplastic member 306b.
_b3 , as in the second embodiment, if the deformation history experienced by both is the same, the index elastic-plastic member 3
06a always undergoes fatigue fracture and breaks before other elastoplastic members 306b.

Therefore, according to the present modification, the same effect as in the second embodiment can be obtained.

The method of manufacturing the elasto-plastic member having the different surface roughness can be implemented without increasing the number of new manufacturing steps. That is, in general, this type of elasto-plastic member gradually reduces the surface roughness gradually from the rough cutting of the surface roughness in the surface finishing step, so that the surface roughness of the plurality of elasto-plastic members substantially match. To produce. On the other hand, in the present modified example, it suffices that the surface finishing operation of the index elastic-plastic member 306a is stopped during the process. Then, for the elasto-plastic member 306b, the surface finishing operation may be performed to the end as usual. Therefore, it can be implemented without increasing the number of new manufacturing steps.

(B) Method Utilizing Difference in Yield Force That is, the index elastic-plastic member 206 of the second embodiment is used.
Instead of a and the elasto-plastic member 206b, an index elasto-plastic member 406a formed by selecting a material having the same outer diameter and a relatively small yield force, and a material having a relatively large yield force are selected. The elasto-plastic member 406b thus configured is used. Also in this case, similarly to the above (A), as the material having a lower yield force shifts its fatigue curve to the lower stress side as a whole, as shown in FIG.
The fatigue curve of 06a shifts downward from the fatigue curve of the elasto-plastic member 406b. Thereby, even if the maximum stress σ _a4 generated in the index elasto-plastic member 406a is equal to the maximum stress σ _b4 generated in the other elasto-plastic members 406b under the same deformation condition, the fracture of the index elasto-plastic member 406a Since the number of repetitions n _{a4 up to} is smaller than the number of repetitions n _b4 of the other elasto-plastic member 406b, the index elasto-plastic member 406a must always be fatigue-ruptured and fractured earlier than the other elasto-plastic members 406b, as described above. Becomes

Therefore, a similar effect can be obtained by this modification.

The two types of fatigue curves shown in FIG. 13 are examples in which materials having different yield forces and different fatigue limits are selected. However, the present invention is not limited to this. Materials having different yield forces but the same fatigue limit are used. You may choose. In this case, the horizontal portion of the fatigue curve coincides with the fatigue curve, but the same effect is obtained in this case as well.

(C) Method Utilizing Difference in Fatigue Limit That is, the index elastic-plastic member 206 of the second embodiment is used.
Instead of a and the elasto-plastic member 206b, an index elasto-plastic member 506a formed by selecting a material having the same outer diameter and a relatively small fatigue limit, and a material having a relatively large fatigue limit are selected. And the configured elastic-plastic member 506b. Also in this case, similarly to the above (B), as the material having a smaller fatigue limit shifts its fatigue curve to a lower stress side as a whole, as shown in FIG. 14, the fatigue curve H of the index elasto-plastic member 506a is better. , Elasto-plastic member 450
The shift is lower than the fatigue curve 6b. Thereby, even if the maximum stresses σ _a5 and σ _b5 of the index elastic-plastic member 506a and the other elastic-plastic members 506b are equal under the same deformation condition, the index elastic-plastic member 506a and the other elastic-plastic members 50
The number of repetitions n _a5 and n _b5 until the break of 6b is given by n _a5 <n _b5
Therefore, as described above, the index elastic-plastic member 506a always breaks before the other elastic-plastic members 506b. Therefore, a similar effect can be obtained by this modification.

A third embodiment of the present invention will be described with reference to FIG. This embodiment is an embodiment in which a plurality of connecting means and members around the connecting means are integrally formed.

Elasto-plastic unit 6 which is a main part of this embodiment
FIG. 15 is a perspective view showing the structure of the 00. In FIG. 15, the elastic-plastic unit 600 includes a block-shaped portion 11b of the connection member 11, a block-shaped portion 13b of the connection member 13, a block-shaped portion 19b of the connection member 19, and a connection member 21 in the first embodiment. Block-shaped part 21 of
b, three clearance members 12 and three clearance members 20
And the index elastic-plastic member 6a and the three elastic-plastic members 6b (see FIG. 1) are integrally formed. That is, the elasto-plastic unit 600 is substantially equivalent to the block-shaped portion 11b, the three clearance members 12, and the block-shaped portion 13b in the first embodiment, and an upper block portion 600a that performs the same function as these, and a block-shaped portion. 19b, a lower block portion 600b substantially equivalent to the three clearance members 20 and the block-shaped portion 21b and performing the same function, and an index connecting means substantially corresponding to the index elasto-plastic member 6a and performing the same function. , And three connecting portions 600d as other connecting means which substantially correspond to the elasto-plastic member 6b and perform the same function as the index connecting portion 600c.

The index connecting portion 600c has a groove 600ca substantially corresponding to the hole 6ad of the index elasto-plastic member 6a of the first embodiment and having the same function. Of the upper block portion 600a, an end portion 600aa on the left front side in the figure.
Are fixed to the plate-like portion 11a (see FIG. 1) of the connecting member 11 by fixing means (not shown), and the end 600ab on the right rear side in the drawing is also connected to the connecting member 1 by fixing means (not shown).
3 is fixed to the plate-shaped portion 13a (the same). Further, of the lower block portion 600b, an end portion 60 on the right rear side in the drawing is shown.
Oba is fixed to the plate-like portion 19a (same) of the connecting member 19 by fixing means (not shown), and the left end 600bb on the front left side of the drawing is also fixed to the plate-like portion 21a (same) of the connecting member 21 by fixing means (not shown). Have been.

The structure other than the above is almost the same as the elastic-plastic damper 3 of the first embodiment.

In the above configuration, the spherical joint 8, the length adjusting member 9, the plate-like portion 11a of the connecting member 11, and the upper block portion 600a constitute a first connecting means, and the spherical joint 15, the length adjusting member The member 16, the plate-like portion 19a of the connecting member 19, and the lower block portion 600b constitute a second connecting means.

In this embodiment configured as described above, the first embodiment is performed based on the functional correspondence clarified above.
The operation is substantially the same as that of the embodiment. That is, when the piping system 1 vibrates with respect to the wall surface or the fixed structure of the building due to an earthquake or the like, the relative displacement is transmitted to the index connecting portion 600c and the connecting portion 600d via the first and second connecting means, Each of them undergoes elasto-plastic deformation, absorbs vibration energy of the piping system 1 and suppresses vibration of the piping system 1. At this time, by forming the groove 600ca in the index connecting portion 600c and concentrating the stress, even under the same deformation condition, the maximum stress of the index connecting portion 600c (= the stress generated in the groove 600ca) is changed to another connecting portion. It is larger than the maximum stress of 600d. As a result, the number of repetitions until breakage of the index connecting portion 600c is smaller than the number of repetitions of the other connecting portion 600d. Therefore, if the deformation history experienced by both is the same, the index connecting portion 600c is higher than the other connecting portion 600d. However, it also causes fatigue fracture and fracture first. Therefore, at least until the index connecting portion 600c breaks, the other connecting portions 600
Since d does not break, the function of the elasto-plastic unit 600, that is, the elasto-plastic damper is at least guaranteed until the index connecting portion 600c breaks, and the index connecting portion 6c is not broken.
Whether or not 00c is broken can be used as an index of the remaining life of the other connecting portion 600d. Therefore, it is only necessary to monitor whether or not the index connecting portion 600c is broken, and when the index connecting portion 600c is found to be broken, the entire elastic-plastic unit 600 may be replaced.

As described above, according to the present embodiment, similarly to the first and second embodiments, it is possible to estimate the time to perform the maintenance of the entire elasto-plastic damper with a simpler method and more accurately than in the past. Therefore, it is possible to eliminate unnecessary component replacement and reduce costs.

In the first to third embodiments, the case where the present invention is applied to an elasto-plastic damper for supporting a piping system of a power plant or a chemical plant is described as an example. However, the present invention is not limited to this. However, it is needless to say that the present invention can be applied between two members that are relatively displaced from each other.

[0059]

According to the present invention, whether or not the indicator connecting means has been broken can be used as an index of the remaining life of the other connecting means, and the remaining life can be estimated to estimate the time for maintenance. In this way, it is possible to estimate the time for maintenance of the entire elastic-plastic damper with a simple method and with high accuracy. Therefore, it is possible to eliminate unnecessary component replacement and reduce costs.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating an entire structure of an elastic-plastic damper according to a first embodiment of the present invention.

FIG. 2 is a schematic layout diagram illustrating an example of a piping system of a power plant, a chemical plant, or the like in which the elasto-plastic damper of FIG. 1 is arranged.

FIG. 3 is a perspective view illustrating a detailed structure of an index elastic-plastic member in FIG.

FIG. 4 is a perspective view illustrating a detailed structure of an index elastic-plastic member in FIG.

FIG. 5 is a diagram showing a fatigue curve for a material constituting the elasto-plastic member.

FIG. 6 is a diagram illustrating detection by an electrical detection unit.

FIG. 7 is a view showing a modified example utilizing stress concentration by a groove.

FIG. 8 is a view showing a modified example utilizing stress concentration by a groove.

FIG. 9 is a diagram showing a modified example utilizing a difference in stress between inside and outside in bending deformation.

FIG. 10 is a perspective view illustrating a detailed structure of an index elastic-plastic member that is a main part of a second embodiment of the present invention.

FIG. 11 is a diagram showing a fatigue curve for an elasto-plastic member.

FIG. 12 is a diagram showing a fatigue curve in a modified example utilizing a difference in surface roughness.

FIG. 13 is a diagram showing a fatigue curve in a modification using a difference in yield force.

FIG. 14 is a diagram showing a fatigue curve in a modification using a difference in fatigue limit.

FIG. 15 is a perspective view illustrating a structure of an elastic-plastic unit that is a main part of a third embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Piping system (member which relatively displaces) 3 Elasto-plastic damper 4 1st connection means 5 2nd connection means 6 Connection means 6a Index elasto-plastic member (index connection means, some connection means) 6b Elasto-plastic member ( 8 Spherical joint 9 Length adjusting member 10 Fastening member 11 Connecting member 12 Clearance member 13 Connecting member 14 Break prevention member 15 Spherical joint 16 Length adjusting member 18 Fastening member 19 Connection Member 20 Clearance member 21 Connection member 22 Break prevention member 206a Index elastic-plastic member (index connecting means, part of connecting means) 206b Elastic-plastic member (other connecting means, most other connecting means) 306a Index elastic-plastic Member (connecting means for index, some connecting means) 306b Elasto-plastic member (other connecting means, most other connecting means) 406a Elasto-plastic member for index (connecting means for index) 406b Elasto-plastic member (other connection means, most other connection means) 506a Index elasto-plastic member (index connection means, some connection means) 506b Elasto-plastic member (other connection means) Means, most other connecting means) 600 Elasto-plastic unit 600a Upper block part (first connecting means) 600b Lower block part (second connecting means) 600c Index connecting part (index connecting means, partial connection) Means) 600d connecting part (other connecting means, most other connecting means)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI F16L 55/02 F16L 55/02

Claims (5)

[Claims] A first connecting means and a second connecting means respectively connected to two members which are displaced relative to each other; and connecting the first connecting means and the second connecting means to each other. An elastic-plastic damper comprising a plurality of connecting means that undergoes elasto-plastic deformation in accordance with the relative displacement between the two members, wherein the plurality of connecting means has a greater number of repetitions until breakage at the time of fatigue failure than other connecting means. An elasto-plastic damper characterized in that it comprises at least one indicator connecting means for reducing the destruction condition as an indicator of the remaining life of the other connecting means. 2. The elasto-plastic damper according to claim 1, wherein, when the two members are displaced relative to each other, the maximum stress generated by the deformation corresponding to the displacement is larger than that of the other coupling means. An elasto-plastic damper characterized in that it is configured to be an elastic plastic damper. 3. The elasto-plastic damper according to claim 1, wherein the connecting means for the indicator has a rougher surface roughness than the other connecting means, a pre-deformation larger than the other connecting means, and a larger amount of deformation than the other connecting means. An elasto-plastic damper having at least one of a low yield force and a fatigue limit smaller than said other connecting means. 4. A first connecting means and a second connecting means which are respectively connected to two members which are relatively displaced from each other, and the first connecting means and the second connecting means are connected to each other. An elastic-plastic damper comprising a plurality of connecting means that undergoes elasto-plastic deformation in accordance with the relative displacement between the two members, wherein only a part of the plurality of connecting means is more than other most connecting means. An elasto-plastic damper characterized in that it is also configured to break due to fatigue failure first for a predetermined period. 5. A first connecting means and a second connecting means which are respectively connected to two members which are displaced relative to each other, and the first connecting means and the second connecting means are connected to each other, In a maintenance method for an elasto-plastic damper comprising a plurality of connecting means that undergoes elasto-plastic deformation according to a relative displacement between the two members, of the plurality of connecting means, only some of the connecting means are replaced with most of the other parts. It is configured so that it is broken by fatigue failure earlier than the connection means only for a predetermined period, and if a breakage of the part of the connection means is found, all of the connection means including most of the connection means which has not been broken A maintenance method for the elasto-plastic damper, characterized in that the connecting means is replaced.