JP4649611B2 - Energy absorbing member provided with metal thin plate and manufacturing method thereof - Google Patents

Description

  The present invention relates to an energy absorbing member provided with a thin metal plate laid on a construction structure in which repeated characteristics are stabilized without exhibiting unstable behavior due to buckling under the action of repeated shearing force due to typhoons or earthquakes, and energy The present invention relates to a method of manufacturing an energy absorbing member provided with a thin metal plate that stabilizes repeated behavior after occurrence of buckling of the thin metal plate included in the absorbing member.

  The shear type energy absorbing member installed in a conventional structure or the like increases the thickness-thickness ratio of the energy absorbing member by increasing the thickness of the energy absorbing member or by reinforcing the energy absorbing member with a rib or the like. Basically, local buckling is prevented from occurring in the shear type energy absorbing member.

  The shear type energy absorbing member as described above is a member that depends on the energy absorbing ability of the material itself used as the metal thin plate, and the energy absorbing capability required of the energy absorbing member depends greatly on the material characteristics of the metal thin plate. is there. Therefore, in the conventional method, this stable in-plane deformation relies on the use of a material having a deformability, and usually a low yield point steel is used as the material, so that local buckling does not occur. Even large deformations are possible.

  As described above, the conventional material used for the energy absorbing member (shear panel) that enables energy absorption is a low yield point steel, and a building using such a low yield point steel as an energy absorbing member is also available. Many have been built. Recently, various devices have been tried for these energy absorbing members in order to improve the performance related to energy absorption and to improve the operability related to the installation of structures and the like.

  For example, JP-A No. 2004-150188 and JP-A No. 2002-013227 are examples of conventional techniques relating to improvement of energy absorption performance and improvement of installation efficiency. However, all of these prior arts use low yield point steel. Therefore, the basic characteristics of the repetition characteristics of the energy absorbing member (shear panel) are technologies that depend on the material properties of the low-yield point steel. It is not a technology that utilizes structural characteristics determined by the shape and stress state of the energy absorbing member for modification.

  On the other hand, Japanese Patent Application Laid-Open No. 2004-042423 is intended to stabilize the load displacement relationship of the thin metal plate. In this prior art, by reinforcing a thin metal plate with a strip, the load-displacement relationship during monotonic loading is stabilized and the plastic deformation capacity is improved, but is this method effective even under repeated loads? It is unknown.

Japanese Patent Laid-Open No. 2004-150188 Japanese Patent Laid-Open No. 2002-013227 Japanese Unexamined Patent Publication No. 2004-042423

  An object of the present invention is to allow a shear-type energy absorbing member installed in a structure or the like to stably absorb energy while being buckled under a repeated history of shearing force action.

  In the prior art, on the premise that buckling does not occur in the energy absorbing member, the width-thickness ratio is reduced by increasing the plate thickness of the energy absorbing member or reinforcing the energy absorbing member with ribs. Through such means, out-of-plane deformation (buckling deformation) does not occur in the energy absorbing member, and in-plane deformation is absorbed by shear deformation of the thin metal plate of the energy absorbing member, in other words, expansion and contraction. Like to do. Therefore, the conventional energy absorbing member has a small plastic deformation ability of the metal thin plate and leads to early breakage.

  On the other hand, the energy absorbing member of the present invention allows out-of-plane deformation due to buckling and increases in-plane deformation as a whole while keeping in-plane deformation small. That is, the energy absorbing member of the present invention allows for out-of-plane deformation at the same time while preventing unstable buckling, and stabilizes the in-plane deformation of the energy absorbing member of the present invention as a whole until large deformation. Objective.

  Further, in the present invention, for example, ordinary steel, aluminum, copper, and alloys thereof, which have not been used as energy absorbing members such as conventional shear panels, are used as energy absorbing members (shear panels). The purpose is to allow absorption. That is, the present invention reduces the weight of the web panel or wall by reducing the weight by using ordinary steel having higher strength than conventional metal thin plates, and the product cost by using inexpensive ordinary steel. It aims at reducing.

  Moreover, it aims at enabling simplification of the enforcement effort accompanying installation of the shear type energy absorption member of this invention by reducing the weight of the shear type energy absorption member of this invention.

  The energy absorption characteristics of the energy absorbing member of the present invention do not depend on the material property values of the metal thin plate itself forming the energy absorbing member, but the structural characteristics (width-thickness ratio, frame shape of the metal thin plate forming the energy absorbing member) , Rib shape, boundary conditions, and stress state), the energy absorption characteristics can be grasped.

  In the load-displacement relationship of the energy absorbing member, buckling defines a state where the stress shown in FIG. 6 is substantially constant and deformation proceeds, that is, a pseudo yield point. Therefore, clarifying the pseudo yield point appearing in the load-displacement relationship of the energy absorbing member clearly evaluates the hysteresis characteristics of the energy absorbing member as shown in FIG. The buckling stress degree is given by the following equation 1.

τ _cr = (kπ ² E / 12 (1-ν ² )) (t / b) ² 1
Here, τ _cr : shear buckling stress, k: buckling coefficient, t: plate thickness, b: plate width, E: Young's modulus, ν: Poisson's ratio, π: circularity.

  Furthermore, the buckling that occurs in the thin metal plate that forms the energy absorbing member can be considered as the initial elastic buckling behavior, so the stress during buckling of the thin metal plate can be quantified as the proof stress using the above formula. It is.

If the set 1 is changed to the shear strength acting on the thin plate,
Q _cr = τ _cr A 2
Here, Q _cr : shear strength, A: cross-sectional area of the thin plate.

  The buckling coefficient k varies depending on the shape of the thin plate (for example, the side length ratio a / b in FIGS. 1 and 2), the peripheral boundary condition of the thin plate, and the stress state. In the case of the thin plate used in the present invention, the buckling coefficient k is given by the following approximate expressions 3 to 6 in consideration that the stress acting on the thin plate is substantially close to a pure shear stress state. This is illustrated in FIG. The points indicated by circles in FIG. 21 indicate the values in the case of 4 peripheral simple support and 4 peripheral fixed support when the side length ratio is 1, 2, and 3.

1) When 4 surroundings are simply supported k = 4.00 + (5.34 / (a / b) ² ) a / b ≦ 1 3
k = 5.34 + (4.00 / (a / b) ² ) a / b ≧ 1 4
2) When the periphery of 4 is fixedly supported k = 5.60 + (8.98 / (a / b) ² ) a / b ≦ 1 5
k = 8.98 + (5.60 / (a / b) ² ) a / b ≧ 16

The value of the buckling coefficient k varies depending on the peripheral boundary conditions (frame rigidity, mounting method) of the thin plate. In the present invention, the value of k varies from the value of k of the four peripheral simple supports to the value of k of the four peripheral fixed supports. Think of it between the values. The buckling coefficient k obtained from FIG. 21 is shown below.
a / b = 1, k = 9.3 to 14.6
a / b = 2, k = 6.3 to 10.4
a / b = 3, k = 7.9 to 9.6

  The side length ratio a / b is restricted by the installation location of the energy absorbing member. When the energy absorbing member is installed on a wall of a general building, the side length ratio a / b is in the range of 0.8 to 2, and thus the value of the buckling coefficient k is in the range of 8 to 14.

  In an energy absorbing member using a conventional low yield point steel, the load-displacement relationship during repeated deformation of the energy absorbing member must be largely dependent on the stress-strain relationship of the material used. However, according to the method of the present invention, the load-displacement relationship at the time of repeated deformation of the energy absorbing member is grasped by the shape of the energy absorbing member without greatly depending on the material characteristics of the thin metal plate of the energy absorbing member. It is possible.

  In order to stabilize the repeated history of the energy absorbing member of the present invention, a large deformation is applied in advance to the metal thin plate constituting the energy absorbing member. When the large deformation is given, detailed data (repetitive load-displacement curve) of the member is collected and arranged, and the performance as the energy absorbing member can be grasped in advance. When installing an energy absorbing member that grasps such performance data in advance in a structure, etc., it is possible to design a detailed structure based on that data, making it possible to design a safer and more stable overall structure. To do.

  An energy absorbing member provided with a metal thin plate to be laid on the structure of the present invention includes a metal thin plate and a frame provided around the metal thin plate, and is preset in the energy absorbing member before the energy absorbing member is installed in the structure. When the energy absorbing member is subjected to repeated deformation after the energy absorbing member is installed on the structure, the energy absorbing member is stably and repeatedly deformed. Further, the two opposite frames form an end plate.

  Moreover, the energy absorbing member of the present invention is laid between each of the beams, columns, and studs of the structure, or as a part of the beams, columns, and studs of the structure.

  Moreover, the energy absorbing member of the present invention is characterized in that the metal thin plate is formed of steel, copper, aluminum and alloys thereof.

  Furthermore, the manufacturing method of the energy absorbing member provided with the metal thin plate laid on the structure of the present invention is repeatedly deformed after the energy absorbing member including the metal thin plate and the frame provided around the metal thin plate is installed in the structure. The energy absorbing member is subjected to a predetermined deformation before the energy absorbing member is installed in a structure so that the energy absorbing member is stably and repeatedly deformed. .

  Further, the energy absorbing member manufacturing method of the present invention is configured such that the preset deformation is larger than the maximum deformation so that a discontinuous portion does not occur in the rigidity of the load displacement relation during an earthquake and a typhoon, and the energy absorbing member Is within the range of three times the maximum deformation so as not to break. Preferably, it is larger than twice the maximum deformation and within a range within three times the maximum deformation so as to have a stable spindle-type load displacement relationship.

  Moreover, the manufacturing method of the energy absorbing member of the present invention is characterized in that the preset deformation is applied by at least one of tension, compression or shear.

  The effect of the energy absorbing member of the present invention will be described in comparison with an energy absorbing member using low yield point steel, which is currently common. The effect of a shear panel type energy absorbing member as shown in FIG. 2 is compared with the result of numerical analysis using a numerical analysis model. The metal thin plate used as a constituent material of the energy absorbing member is, for example, two types of steel materials as shown in FIG. The metal thin plate used for the energy absorbing member of the present invention was JIS SS400. The result is shown in FIG. When the energy absorbing member of the present invention vibrates due to an earthquake or a typhoon, as shown in FIG. 5, the stress Q (kN) tends to increase as the deformation amount γ increases. Since the stress Q (kN) tends to decrease with the decrease, the structure in which the energy absorbing member of the present invention is laid can attenuate the vibration together with the stable vibration.

  In the energy absorbing member that has not been subjected to large deformation in advance as shown in FIG. 6, the stress Q (kN) rapidly decreases or the deformation increases with a constant stress as the deformation γ increases in the load-displacement relationship. Or a sudden change in stiffness. By applying a large deformation in advance to the thin metal plate having such a tendency as shown in FIG. 3 based on the concept of FIG. 4, the repeated load-displacement relationship changes as shown in FIG. This load-displacement relationship is very stable and is sufficiently effective as an energy absorbing member laid on the structure. Furthermore, this load-displacement relationship is a hysteresis curve that is the same as or more stable than the repeated load-displacement relationship of the energy absorbing member using the low yield point steel, which is the prior art shown in FIG.

  The flange shapes used for the energy absorbing members of the present invention and the prior art are the same, but the web shapes used for the energy absorbing members are different from each other. The web shape shown in FIG. 5 of the present invention is a square plate having a thickness of 2 mm and a square of 500 mm, and the web shape shown in FIG. 7 of the prior art is a square plate having a thickness of 6 mm and a square of 350 mm. Therefore, the web shape according to the present invention can be reduced to about 60% by weight.

  Further, the ordinary steel (SS400 in the embodiment) used in the present invention is very cheap compared to the low yield point steel used in the prior art, and the assembly labor and transportation costs due to welding and the like are also low. It was. Moreover, giving large deformation to the ordinary steel used as in the present invention in advance makes it possible to collect and organize detailed data of the member when applying large deformation, so that the energy absorbing member can be structured. When installing in a location, etc., detailed structural design was possible based on the data, enabling safer and more stable structural design.

  In order to make the energy absorbing member provided with the thin metal plate laid on the construction structure of the present invention an energy absorbing member having a stable repeated history, buckling is accompanied by a decrease in yield strength or rigidity during the repeated history. It is to eliminate the occurrence of deformation. For this purpose, it is necessary to eliminate the balance between the load and displacement that leads to load reduction and constant deformation (the state in which buckling occurs). In order to eliminate the occurrence of the buckling deformation, a tension field that induces a large out-of-plane deformation is generated in advance in the thin metal plate constituting the energy absorbing member, and the out-of-plane deformation is generated in the thin metal sheet. If repeated displacement can be suppressed to such an extent that sudden balance branching does not occur within the deformation range, the energy absorption member has a stable repeated history.

  In other words, in the present invention, the amount of repeated displacement applied to the energy absorbing member that is expected to occur due to a typhoon or an earthquake is defined in advance. In the present invention, based on the defined displacement amount, a large displacement amount that is equal to or greater than the defined displacement amount is given to the energy absorbing member in advance. As a result, the energy absorbing member of the present invention does not exhibit unstable deformation behavior during repeated typhoons or earthquakes.

Further, preferably, before installing the energy absorbing member of the present invention in the structure, it is about three times the maximum displacement amount from the maximum displacement amount due to the disturbance predicted or assumed after installation in the structure, preferably the maximum displacement amount. By giving the energy absorbing member a deformation of about twice the maximum displacement to about three times the maximum displacement in advance, after the energy absorbing member is installed in the structure, it will exhibit stable energy absorbing ability against disturbance become. In order for the energy absorbing member of the present invention to obtain such an effect, as shown in FIG. 3, as shown in FIG. 1 and FIG. 2, a load-displacement relationship is exhibited in the case of repeated deformation accompanied by large deformation. A shear load must be applied to the energy absorbing member shown. The range of the thickness of the thin plate of the energy absorbing member ranges from about the elastic buckling limit width-thickness ratio (b / t) _e when subjected to a shear load to about three times that.

Elastic buckling limit width / thickness ratio (b / t) _e is obtained by substituting τcr in Equation 1 with τ _y as the shear yield stress of the thin plate and taking Poisson's ratio as 0.3 and taking the width / thickness ratio b / t. Can be sought. That is, the elastic buckling limit width-thickness ratio (b / t) _e is expressed by the following formula 7.
(B / t) _e = (kE / τy) ^1/2 7
In the energy absorbing member of the present invention, the range of the width-thickness ratio b / t that effectively acts as the energy absorbing member is expressed by the following equation using the elastic buckling limit width-thickness ratio (b / t) _e obtained by Equation 7. 8 can be expressed.
(B / t) = (b / t) _e -3 (b / t) _e 8

  An example of the energy absorbing member of the present invention is a rectangular thin plate made of a metal thin plate as shown in FIGS. 1 and 2, and a frame arranged so as to maintain a rectangular thin plate shape around the rectangular thin plate. , Is composed of. In the energy absorbing member of the present invention, a load acts in the arrow direction shown in FIGS. At this time, the rectangular thin plate of the energy absorbing member of the present invention undergoes shear deformation. As shown in FIG. 4, the shear deformation applied in advance to the rectangular thin plate is a large deformation of about three times from the maximum response displacement assumed by the disturbance acting after the energy absorbing member of the present invention is installed on the structure. By experiencing in advance, the history behavior of the energy absorbing member after installation is stabilized as shown in FIG.

Example 1
The metal thin plate (web) forming the energy absorbing member is a square flat plate having a plate thickness of 2 mm and a length of four sides of 500 mm. A flange plate (frame) having a thickness of 12 mm and a width of 200 mm is attached to the left and right side surfaces of the square flat plate, and end plates (frames) are attached to the upper and lower sides of the square flat plate. The energy absorbing member having the above-described shape (shown in FIG. 2) is subjected to a shear stress that gives a deformation of about 3 times from the maximum response displacement. The results of numerical analysis of the energy absorbing member to which shear stress is applied are shown in FIGS. In each figure, the vertical axis represents the magnitude of the acting shear force, and the horizontal axis represents the shear deformation angle.

The metal sheet used for this numerical analysis is SS400 plain steel. FIG. 8 shows the stress-strain relationship in the plastic region of SS400 plain steel. Young's modulus is 205000 N / mm ² and Poisson's ratio is 0.3.

  When the energy absorbing member is made of a thin metal plate and a disturbance is applied without experiencing large deformation, the energy absorbing member does not have the spindle-type load-displacement relationship shown in FIG. It exhibits a repeated load-displacement relationship that exhibits unstable deformation behavior. On the other hand, like the energy absorbing member of the present invention, the deformation behavior after the large deformation as shown in FIG. 3 is extremely stable as shown in FIG. The mold exhibits a repeated load-displacement relationship.

Example 2
The preferable example which attached the energy absorption member 1 comprised from the metal thin plate of this invention to various structures is illustrated in FIGS. In the method of attaching the energy absorbing member 1 composed of the thin metal plate 2 of the present invention, when the beam 5 and the column 6 of the building structure are formed of steel and concrete, the energy absorbing member 1 is changed to the beam 5 and the column 6. Fasten with bolts (not shown). Moreover, when the beam 5 and the column 6 of the building structure are formed of wood, the energy absorbing member 1 is fastened to the beam 5 and the column 6 with nails and screws (not shown).

  The time when the energy absorbing member 1 is attached to the structure may be any time during new construction, during seismic reinforcement, and during seismic retrofit. Moreover, the attachment position to the structure of the energy absorption member 1 of this invention can be attached as a part of the structure pillar 4 shown in FIG. FIG. 10 shows an example in which the energy absorbing member 1 is attached as an intermediate member between both the intermediate pillar 4 and the wall member 7 of the structure. Moreover, as shown in FIG. 11, the energy absorption member 1 can also be attached as the wall member 7 of a structure. Furthermore, as shown in FIG. 12, the energy absorbing member 1 is arranged at the joint position of the beam 5 and the column 6 of the structure, and as shown in FIG. 13, the energy absorbing member 1 is attached to the structure diagonal member 8 (beam link member). ) And as a part of the beam 5, and as shown in FIG. 14, the energy absorbing member 1 is arranged as a boundary beam of a part of the beam 5 between the columns 6 and 6 of the structure. You can also.

Example 3
In the present invention, the deformation can be applied in advance by the diagonal deformation of the thin metal plate, and the energy absorbing member can be formed by laying the thin metal plate directly on the structure. On the other hand, in this invention, in order to maintain the periphery shape of an energy absorption member, a frame (flange board) can be attached to the upper and lower sides and right and left of a thin metal plate as shown in FIGS.

  As shown in FIGS. 15 and 16, the energy absorbing member 1 of the present invention is formed from a rectangular thin metal plate 1 and a frame 3 (flange) surrounding the thin metal plate in order to maintain its shape. . In addition, as shown in FIG. 16, the upper and lower two sides facing each other can be used as an end plate 3 ′, and the left and right two sides can be used as the frame 3. In addition to the above configuration, the following energy absorbing member can be formed.

a) Energy absorbing member (not shown) provided with a mounting hole or mounting screw in the frame
b) Energy absorbing member provided with a plurality of metal thin plates in parallel (FIG. 17)
c) Energy absorbing member provided with a plurality of metal thin plates in series (FIG. 18)
d) Energy absorbing member (not shown) combining the above a) and b)
e) Energy absorbing member provided with an attachment plate 9 covering the surface of the thin metal plate (FIG. 19)
f) Energy absorbing member provided with a thin metal plate subjected to surface treatment such as a coating film, a heat insulating material, and a fireproof coating 10 (FIG. 20).

  The energy absorbing member of the present invention is a member that stabilizes energy absorption under a repetitive history such as an earthquake and a typhoon, and this energy absorbing member is attached to an existing structure as well as a new structure. be able to.

  In addition, the energy absorbing member of the present invention can be stabilized by a very inexpensive method for stabilizing the cyclic history characteristics of the thin metal plate, so that the structure is subjected to repeated history such as earthquakes and typhoons. This greatly contributes to stabilization.

The conceptual diagram of the shear wall of an energy absorption member is shown. The conceptual diagram of the shear panel of an energy absorption member is shown. The large deformation repetition process of an energy absorption member is shown. The conceptual diagram of the empirical deformation that was loaded and the deformation caused by the disturbance during the earthquake is shown. It is a figure which shows the repeated load-displacement relationship by the disturbance at the time of an earthquake, etc. of the energy absorption member after loading the large deformation of this invention, and shows the step where repeated displacement increases gradually. It is a figure which shows the repeated load-displacement relationship by the disturbance at the time of an earthquake of the energy absorption member of the comparative example which does not load a large deformation | transformation, and shows the step which a repeated displacement increases gradually. It is a figure which shows the repetitive load-displacement relationship at the time of using the low yield point steel (LY100) for the conventional energy absorption member, and shows the step where repetitive displacement increases gradually. It is a figure which shows the plastic region material characteristic of SS400 of JIS used for the energy absorption member of this invention, and the low yield point steel (LY100) used for the conventional energy absorption member. The example which attached the energy absorption member comprised from the metal thin plate of this invention as a part of the pillar 4 of a structure is shown, (a) shows a front, (b) is a figure which shows a cross section. The example which attached the energy absorption member comprised from the metal thin plate of this invention as an intermediate member of both the pillar 4 of a structure and the wall member 7 is shown, (a) shows a front, (b) is a cross section. FIG. The example which attached the energy absorption member comprised from the metal thin plate of this invention as a wall member of a structure is shown, (a) shows a front, (b) is a figure which shows a cross section. The example which has arrange | positioned the energy absorption member comprised from the metal thin plate of this invention in the junction position of the pillar and beam of a structure is shown, (a) shows a front, (b) is a figure which shows a cross section. The example which arrange | positions the energy absorption member comprised from the metal thin plate of this invention as a part of the beam 5 between the diagonal members 8 (beam link member) of a structure is shown, (a) shows a front, (B) is a figure which shows a cross section. The example which has arrange | positioned the energy absorption member comprised from the metal thin plate of this invention as a boundary beam as a part of beam between the pillars of a structure is shown, (a) shows a front, (b) It is a figure which shows a cross section. The energy absorption member of this invention formed from the thin metal plate and the frame (flange) surrounding the thin metal plate in order to maintain the shape is shown, (a) shows the front, (b) shows the aa cross section. FIG. In order to maintain the shape of the metal thin plate, the energy absorbing member of the present invention in which a part of the frame surrounding the metal thin plate is formed from the end plate, (a) shows the front, (b) shows It is a figure which shows the aa cross section. The energy absorption member of this invention provided with two or more metal thin plates (web) in parallel is shown, (a) shows a front, (b) shows an aa cross section, (c) shows a bb cross section. It is. The energy absorption member of this invention provided with two or more metal thin plates in series is shown, (a) shows a front, (b) shows an aa cross section, (c) is a figure which shows a bb cross section. The energy absorption member of this invention provided with the attached board which covers the surface of a metal thin plate is shown, (a) shows a front, (b) shows an aa cross section, (c) shows a bb cross section. It is. The energy absorption member of this invention provided with the metal thin plate by which surface treatments, such as a paint film, a heat insulating material, and a fireproof film, were shown, (a) shows a front, (b) shows an aa section, (c ) Is a diagram showing a bb cross section. The relationship between the buckling coefficient k and the side length ratio of the thin plate used for the energy absorbing member of the present invention is shown, and the curves for 4 peripheral simple support and 4 peripheral fixed support are shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Energy absorption member 2 Thin plate, Web 3 Frame, flange 3 'End plate 4 Inter-column 5 Beam 6 Column 7 Wall member 8 Diagonal material 9 Attached plate 10 Paint, heat insulating material, fireproof coating

Claims (7)

An energy absorbing member comprising a thin metal plate laid on a structure,
The energy absorbing member includes a metal thin plate and a frame provided around the metal thin plate,
Before installing the energy absorbing member on the structure, the energy absorbing member is stabilized when subjected to repeated deformation after the energy absorbing member is installed on the structure by applying a predetermined deformation to the energy absorbing member. Repeatedly deform,
An energy absorbing member provided with a thin metal plate.   The energy absorbing member according to claim 1, wherein the two opposite frames form an end plate.   The energy absorbing member according to claim 1, wherein the energy absorbing member is laid between a beam, a column, and a stud of each of the structures, or as a part of a beam, a column, and a stud of the structure.   The energy absorbing member according to claim 1, wherein the metal thin plate is formed of steel, copper, aluminum, and an alloy thereof. A method for manufacturing an energy absorbing member comprising a thin metal plate laid on a structure,
When the energy absorbing member including a metal thin plate and a frame provided around the metal thin plate is repeatedly deformed after being installed in a structure, the energy absorbing member is configured to stably deform repeatedly. Before the member is installed in the structure, a predetermined deformation is applied to the energy absorbing member.
The manufacturing method of the energy absorption member provided with the metal thin plate characterized by the above-mentioned.   6. The method of manufacturing an energy absorbing member according to claim 5, wherein the preset deformation is larger than a maximum deformation caused by an earthquake and a typhoon and within a range not more than three times the maximum deformation.   The method of manufacturing an energy absorbing member according to claim 6, wherein the preset deformation is applied by at least one of tension, compression, and shear.

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