JP7679251B2 - Brace structure - Google Patents

Description

The present invention relates to a brace structure.

For example, Patent Document 1 discloses a vibration suppression brace configuration that includes an outer brace component, a steel inner brace component disposed in a retaining hole of the outer brace component, and a viscoelastic layer interposed between the circumferential surface of the inner brace component and the inner circumferential surface of the outer brace component. Both sides of the vibration suppression brace configured in this way are connected to the framework of the building.
Patent Document 2 discloses a vibration damper that includes three or more steel plates and a viscoelastic body bonded between the steel plates, with at least one end of the steel plates being connected to a connecting member on the frame side of a building via a mounting member. In this vibration damper, at least one layer of the viscoelastic body adjacent to the mounting member or connecting member across the steel plate is extended toward the mounting member or connecting member to a position at least flush with the end face of the mounting member or connecting member on the viscoelastic body side.
Patent Document 3 discloses a vibration damper configuration including an inner member attached to one portion of a framework of a structure and on which an axial force acts, an outer member attached to the other portion of the framework and on which an axial force acts, and a viscoelastic body interposed between the inner member and the outer member. In this configuration, the inner member has a polygonal tubular portion. The outer member has a plurality of band plates arranged independently and facing each other on the outer circumferential surface of the tubular portion, a tube covering the inner member and the band plates from the outer surface side, and a filler that is injected and solidified along the inner surface of the tube to integrate the tube and the band plates. The viscoelastic body is a sheet-like viscoelastic body, and is interposed between the outer circumferential surface of the tubular portion and the band plates with both sides in close contact with each other.

The configurations disclosed in Patent Documents 1 to 3 are all brace structures equipped with vibration dampers using viscoelastic materials. In such configurations, in order to increase the damping force, the vibration dampers can be lengthened in the axial direction of the extension of the brace, but there is a limit to the range in which the vibration dampers (viscoelastic materials) can be provided on the brace, which creates problems with the fit of the vibration dampers. In addition, if the vibration dampers are made longer, there may be concerns about a reduction in the amount of energy absorbed due to elastic deformation of the steel parts, buckling, etc.
In addition, when ordinary rubber is used as the viscoelastic body, the damping performance may not be fully exhibited. This is because ordinary rubber is highly temperature-dependent, and mechanical properties such as rigidity and damping performance decrease as the temperature rises. The temperature of the viscoelastic body can easily rise due to external factors such as air temperature and direct sunlight, so the viscoelastic body may not be able to efficiently exhibit its damping performance depending on the installation environment of the vibration damper in which the viscoelastic body is installed. Alternatively, the temperature of the viscoelastic body may rise when the viscoelastic body absorbs vibration energy during an earthquake, so if the viscoelastic body repeatedly absorbs vibration during an earthquake, the temperature of the viscoelastic body may rise accordingly, and the damping performance may not be fully exhibited.
Therefore, there is a demand for a brace structure that can exert a high damping force while preventing the vibration damper from becoming too large.

Japanese Patent Application Publication No. 3-262881 JP 2016-56605 A Patent No. 4950913

The problem that this invention aims to solve is to provide a brace structure that can exert a high damping force while suppressing the increase in size.

In order to solve the above problems, the present invention employs the following means.
In other words, the brace structure of the present invention is a brace structure with a built-in vibration damper, comprising a core material, an outer steel pipe with a cement-based hardened body on the inside thereof which is arranged so as to be movable relative to the core material, and a vibration damper which is joined to the core material and the cement-based hardened body and has high-damping rubber that damps the relative movement between the core material and the outer steel pipe, and which is characterized in that the vibration damper and the core material are fastened with bolts.
According to this configuration, the vibration damper is formed to include high-damping rubber, which is a viscoelastic body and has high damping performance. This improves the damping performance of the vibration damper. Furthermore, high-damping rubber has low temperature dependency, and the damping performance is not likely to decrease even if the temperature rises due to external factors such as air temperature and direct sunlight, or due to the absorption of vibration energy. In this way, by using high-damping rubber as the viscoelastic body of the vibration damper realized as a so-called viscoelastic damper, it is possible to achieve a configuration that improves the damping performance and enables the damping performance to be stably exhibited.
Because the damping performance can be improved efficiently in this way, the total amount of viscoelastic body required to achieve the damping performance required of the vibration damper is reduced, which may reduce the length of the vibration damper in the axial direction of the brace structure and prevent it from becoming too large.
Here, while it is not easy to adhere such high-damping rubber to steel materials at construction sites, etc., in the above-mentioned brace structure, the vibration damper formed with high-damping rubber is constructed by fastening it to a core material with bolts, making assembly and construction at the construction site easy.
In this way, it is possible to provide a brace structure that is capable of exerting a high damping force while suppressing an increase in size.

In one aspect of the present invention, the brace structure of the present invention has a core material having a cross-shaped cross section or an H-shaped cross section, the core material having a plate-shaped portion, the vibration dampers being provided on both sides of the plate-shaped portion, and each of the vibration dampers being joined to the plate-shaped portion by a bolt that passes through them.
With this configuration, by making the core material have a cross-shaped or H-shaped cross-section, it becomes possible to provide multiple vibration dampers in a limited space, making it possible to exert a high damping force while preventing the brace structure from becoming too large.
Furthermore, when the core material is a steel pipe or the like and has a portion with an annular cross-sectional shape, when fastening the vibration damper to the surface of the core material with bolts, it is necessary to insert one's hand from the axial end of the core material into the inside of the annular portion, which makes assembly and construction difficult. In contrast, in the above-mentioned configuration, the core material does not have a portion with an annular cross-sectional shape and is structured so that all surfaces of the core material can be easily contacted from the outside, so that the vibration damper can be easily fastened to the surface of the core material with bolts.
Furthermore, vibration dampers are provided on both sides of the plate-like portion that constitutes the core material, and each vibration damper is joined to the plate-like portion by a bolt that penetrates them. In other words, since multiple vibration dampers can be fastened together to the core material with one bolt, the number of bolts used can be reduced and the size of the brace structure can be further prevented from increasing, compared to when each vibration damper is fastened to the core material with a bolt.

In one aspect of the present invention, the brace structure of the present invention comprises a vibration damper comprising a first outer steel plate and a second outer steel plate provided on opposite sides of the high-damping rubber, the first outer steel plate having an outer edge portion formed so that its outer dimension is larger than that of the high-damping rubber when the vibration damper is viewed in a plane, the outer edge portion being fastened to the core material by the bolts, and the second outer steel plate being joined to the cement-based hardened body.
According to this configuration, the first outer steel plate has a larger outer dimension than the high-damping rubber, so that the outer edge protrudes outward beyond the high-damping rubber. The vibration damper can be joined to the core material by fastening the outer edge to the core material with bolts. Furthermore, the vibration damper is joined to the cementitious hardened body by joining the second outer steel plate to the cementitious hardened body. In this way, it is possible to configure the high-damping rubber to damp the relative movement between the core material and the outer steel pipe.

The present invention makes it possible to provide a brace structure that can exert a high damping force while suppressing size increase.

FIG. 2 is a diagram showing a configuration of a brace structure according to an embodiment of the present invention. 2 is a cross-sectional view of the brace structure according to the first embodiment of the present invention as viewed from the axial direction, and is a cross-sectional view taken along the line II in FIG. 1. 2. FIG. 2 is a cross-sectional view taken along the line II-II of FIG. FIG. 11 is a cross-sectional view showing a configuration of a modified example of the brace structure according to the first embodiment of the present invention. FIG. 11 is a cross-sectional view showing the configuration of another modified example of the brace structure according to the first embodiment of the present invention. FIG. 5 is a cross-sectional view of a brace structure according to a second embodiment of the present invention, as viewed from the axial direction.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a brace structure according to the present invention will be described with reference to the accompanying drawings.
[First embodiment]
The configuration of a brace structure according to an embodiment of the present invention is shown in FIG.
As shown in Fig. 1, a brace structure 10A according to this embodiment is provided in a column-beam structure 2 that constitutes a skeleton 1 of a structure. The column-beam structure 2 includes a plurality of columns 3 and beams 4. The plurality of columns 3 are arranged at intervals in the horizontal direction. Each column 3 extends in the vertical direction. The beams 4 are arranged at intervals in the vertical direction. Each beam 4 extends in the horizontal direction and is installed between adjacent columns 3.

The brace structure 10A is provided between columns 3 adjacent to each other in the horizontal direction and beams 4 located above and below each other. The brace structure 10A is provided so as to extend diagonally between two columns 3 adjacent to each other and two beams 4 located above and below each other. Both ends of the brace structure 10A are joined to brackets 12 provided at a first joint J1 and a second joint J2, which are joints between the columns 3 and the beams 4.
Fig. 2 is a cross-sectional view of the brace structure according to the first embodiment of the present invention as viewed from the axial direction, taken along the line II-II of Fig. 1. Fig. 3 is a cross-sectional view taken along the line II-II of Fig. 2.
As shown in Figures 2 and 3, the brace structure 10A mainly includes a core material 21A, an outer steel pipe 22A, and a vibration damper 30A.
The core material 21A extends in the axial direction Da of the brace structure 10A. One end 21s of the core material 21A is joined to the bracket 12 of the second joint J2. The other end 22t side of the core material 21A is inserted into the outer steel pipe 22A. In the outer steel pipe 22A, a gap is formed between the other end 22t and the bracket 12 of the first joint J1. As shown in FIG. 2, in this embodiment, the core material 21A has a cross-shaped cross section perpendicular to the axial direction Da of the brace structure 10A (direction perpendicular to the paper surface in FIG. 2). The core material 21A has four plate-shaped portions 21p extending in all directions from a central portion 21c of the cross section of the core material 21A. The four plate-shaped portions 21p are joined to each other.

As shown in Fig. 3, the outer steel pipe 22A extends in the axial direction Da of the brace structure 10A. One end 22s of the outer steel pipe 22A is joined to the bracket 12 of the first joint J1. The other end 22t of the outer steel pipe 22A is spaced from the bracket 12 of the second joint J2 by a gap in the axial direction Da. As shown in Fig. 2, in this embodiment, the outer steel pipe 22A is, for example, a circular steel pipe having a circular cross-sectional shape perpendicular to the axial direction Da.
A cement-based hardened body 24 is provided on the inside of the outer steel pipe 22A. The cement-based hardened body 24 is made of, for example, mortar. The outer steel pipe 22A is fixed to the cement-based hardened body 24. The cement-based hardened body 24 is joined only to the second outer steel plate 32 of the vibration damper 30A described later, and is provided with a gap S1 between the core material 21A, the viscoelastic body 33 of the vibration damper 30A, and the first outer steel plate 31A.
With the above-described configuration, the outer steel pipe 22A is arranged to be movable relative to the core material 21A in the axial direction Da of the brace structure 10A toward the second joint J2 or away from the second joint J2.

The vibration dampers 30A damp the relative movement between the core material 21A and the outer steel pipe 22A. The vibration dampers 30A are joined to the core material 21A and the cement-based hardened body 24. In this embodiment, four vibration dampers 30A are provided in the circumferential direction around the cross-sectional center 21c of the core material 21A. In this embodiment, each vibration damper 30A is disposed between two adjacent plate-shaped portions 21p in the circumferential direction around the cross-sectional center 21c of the core material 21A. As a result, in each of the plate-shaped portions 21p constituting the core material 21A, a vibration damper 30A is provided on both sides of the plate-shaped portion 21p.
As shown in Fig. 3, in this embodiment, the vibration damper 30A is provided over the entire area (total length) where the core material 21A and the outer steel pipe 22A overlap in the axial direction Da. The vibration damper 30A includes a first outer steel plate 31A, a second outer steel plate 32, and a viscoelastic body 33. The vibration damper 30A is configured by stacking the first outer steel plate 31A, the second outer steel plate 32, and the viscoelastic body 33 in a direction perpendicular to the axial direction Da.
The first outer steel plate 31A and the second outer steel plate 32 are provided on both sides of the viscoelastic body 33. As shown in FIG. 2, the second outer steel plate 32 is provided at an inclination of, for example, 45 degrees with respect to the two plate-shaped portions 21p that are perpendicular to each other. The second outer steel plate 32 is provided with a plurality of stud bolts 34 integrally on a surface 32f opposite to the viscoelastic body 33. The surface 32f of the second outer steel plate 32 is in contact with the cement-based hardened body 24 and is fixed to the cement-based hardened body 24. The plurality of stud bolts 34 are embedded in the cement-based hardened body 24. In this way, the second outer steel plate 32 is joined to the cement-based hardened body 24.

The first outer steel plate 31A is formed so that the outer dimensions of the vibration damper 30A are larger than those of the viscoelastic body 33 when viewed in a plan view from the stacking direction Ds of the first outer steel plate 31A, the second outer steel plate 32, and the viscoelastic body 33. The first outer steel plate 31A integrally has a base plate portion 31a formed parallel to the second outer steel plate 32 and an outer edge portion 31b extending from both ends of the base plate portion 31a along the plate-like portions 21p on both sides. The outer edge portion 31b protrudes outward from the viscoelastic body 33 when viewed in a plan view from the stacking direction Ds. In this embodiment, the outer edge portion 31b extends at an angle of 45 degrees toward the second outer steel plate 32 with respect to the base plate portion 31a when viewed in the axial direction Da. The first outer steel plate 31A is provided with the outer edge portions 31b on both sides aligned along the two adjacent plate-like portions 21p. As a result, a gap S3 (see FIG. 2) is formed between two adjacent plate-shaped portions 21p and the first outer steel plate 31A.
The outer edge portion 31b is fastened to the core material 21A by bolts 40 and nuts 41. In this embodiment, the first outer steel plates 31A of the two vibration dampers 30A arranged on both sides of each plate-shaped portion 21p are fastened to each other by bolts 40 and nuts 41 that penetrate the outer edge portions 31b and plate-shaped portions 21p of both vibration dampers 30A. In other words, the bolts 40 and nuts 41 are shared between two vibration dampers 30A adjacent to each other in the circumferential direction.

The viscoelastic body 33 damps the relative movement between the core material 21A and the outer steel tube 22A in the axial direction Da perpendicular to the lamination direction Ds of the first outer steel plate 31A and the second outer steel plate 32. The viscoelastic body 33 is a high-damping rubber having a higher damping performance than normal rubber. The viscoelastic body 33 preferably contains at least one rubber material selected from the group consisting of acrylic, diene, styrene, and isoprene rubbers. In this embodiment, for example, a rubber material containing isoprene-based rubber is used as the viscoelastic body 33. Isoprene-based rubber has a high initial rigidity. In addition, isoprene-based rubber has a low temperature dependency. Therefore, even if the temperature rises due to external factors such as air temperature and direct sunlight, or due to the absorption of vibration energy, the damping performance is not easily reduced. Furthermore, isoprene-based rubber has a low frequency dependency. The viscoelastic body 33 is produced by mixing synthetic rubber, such as isoprene rubber, and natural rubber, to which a damping agent, an anti-aging agent, and the like are added.
The vibration damper 30A including such a viscoelastic body 33 is manufactured in a factory by vulcanizing and bonding the viscoelastic body 33, the first outer steel plate 31A, and the second outer steel plate 32 under predetermined high temperature and high pressure conditions. When assembling the brace structure 10A, the vibration damper 30A manufactured in advance is attached to the core material 21A with the bolts 40 and nuts 41.

In such a vibration damper 30A, the displacement of the core material 21A in the axial direction Da is transmitted to the first outer steel plate 31A via the bolt 40. Also, the displacement of the outer steel pipe 22A in the axial direction Da is transmitted to the second outer steel plate 32 via the cement-based hardened body 24 and the multiple stud bolts 34. The viscoelastic body 33 using high damping rubber attenuates the relative displacement between the first outer steel plate 31A and the second outer steel plate 32. As a result, the vibration damper 30A attenuates the relative movement between the core material 21A and the outer steel pipe 22A. Therefore, in the brace structure 10A, when a tensile force or a compressive force is applied, the core material 21A and the outer steel pipe 22A resist, and the core material 21A and the outer steel pipe 22A form a mechanism for transmitting forces to each other by the shear force of the viscoelastic body 33 and the cement-based hardened body 24 between them. Specifically, the core material 21A and the outer steel pipe 22A bear tensile and compressive forces. Shear forces are transmitted between the core material 21A and the viscoelastic body 33 via bolts 40, and between the viscoelastic body 33 and the cement-based hardened body 24 via stud bolts 34. Shear forces are transmitted between the cement-based hardened body 24 and the outer steel pipe 22A by adhesion. The cement-based hardened body 24 resists as a buckling restraint material for the core material 21A and the outer steel pipe 22A. This also works in the brace structures of the various modifications described in detail after this embodiment.

The brace structure 10A as described above has a built-in vibration damper 30A and comprises a core material 21A, an outer steel pipe 22A which is arranged to be able to move relative to the core material 21A and has a cement-based hardened body 24 on its inside side, and a vibration damper 30A which is joined to the core material 21A and the cement-based hardened body 24 and has a viscoelastic body (high damping rubber) 33 that damps the relative movement between the core material 21A and the outer steel pipe 22A, and the vibration damper 30A and core material 21A are fastened together with bolts 40.
According to this configuration, the viscoelastic body 33 of the vibration damper 30A is a high-damping rubber having high damping performance. Therefore, the damping performance of the vibration damper 30A is improved. Furthermore, high-damping rubber has a smaller temperature dependency than normal rubber, and the damping performance is less likely to decrease even if the temperature rises due to external factors such as air temperature and direct sunlight, or due to the absorption of vibration energy. In this way, by using high-damping rubber for the viscoelastic body 33 of the vibration damper 30A realized as a so-called viscoelastic damper, it is possible to improve the damping performance and achieve a configuration that can stably exhibit the damping performance.
Since the damping performance can be improved efficiently in this manner, the total amount of the viscoelastic body 33 required to realize the damping performance required of the vibration damper 30A is reduced. Therefore, it is possible to reduce the length of the vibration damper 30A in the axial direction Da of the brace structure 10A and suppress an increase in size.
Here, while it is not easy to adhere such high-damping rubber to steel materials at construction sites and the like, in the brace structure 10A described above, the vibration damper 30A formed with high-damping rubber is constructed by fastening it to the core material 21A with bolts 40, making it easy to assemble and install at the construction site.
In this way, it is possible to provide a brace structure 10A that is capable of exerting a high damping force while suppressing an increase in size.

Generally, high-damping rubber is manufactured and sold as a unit by vulcanizing and bonding it to steel plates under specified high temperature and pressure conditions in a factory. For this reason, it is difficult to procure it as a single unit that is not bonded to the steel plate, process it into any shape, and bond it to a core material to form a vibration control damper.
Even if the high damping rubber could be procured as a single unit, special equipment would be required to vulcanize and bond it to the core material 21A, for example, and therefore assembly at the construction site would not be easy.
In contrast, in the present embodiment, the vibration damper 30A and brace structure 10A can be constructed by fastening the high-damping rubber manufactured as a unit to the core material 21A with bolts, which makes assembly and construction at the construction site easier, as described above.

In addition, the core material 21A has a cross-shaped cross section, and has a plate-shaped portion 21p. Vibration dampers 30A are provided on both sides of the plate-shaped portion 21p, and each of the vibration dampers 30A and the plate-shaped portion 21p are joined by bolts 40 that pass through them.
According to this configuration, four vibration dampers 30A can be incorporated between the four plate-like portions 21p that make up the core material 21A. In this way, it is possible to provide multiple vibration dampers 30A in a limited space, and it is possible to exert a high damping force while suppressing an increase in the size of the brace structure 10A.
Furthermore, when the core material 21A is a steel pipe or the like and has a portion with an annular cross-sectional shape, assembly and construction are not easy because it is necessary to insert a hand from the end of the axial direction Da of the core material 21A into the inside of the annular portion when fastening the vibration damper 30A to the surface of the core material 21A with the bolt 40. In contrast, in the above-mentioned configuration, the core material 21A does not have a portion with an annular cross-sectional shape and is structured so that all surfaces of the core material 21A can be easily contacted from the outside, so that the vibration damper 30A can be easily fastened to the surface of the core material 21A with the bolt 40.
Furthermore, vibration dampers 30A are provided on both sides of plate-like portions 21p constituting the core material 21A, and each of the vibration dampers 30A and the plate-like portions 21p are joined by bolts 40 that penetrate them. In other words, since a plurality of vibration dampers 30A can be fastened together to the core material 21A with one bolt 40, the number of bolts 40 used can be reduced and the size of the brace structure 10A can be further prevented from increasing, compared to the case where each vibration damper 30A is fastened to the core material 21A with a bolt 40.

The vibration damper 30A also comprises a first outer steel plate 31A and a second outer steel plate 32 which are provided on opposite sides of the viscoelastic body (high damping rubber) 33, and the first outer steel plate 31A has an outer edge portion 31b formed so that its outer dimensions are larger than those of the viscoelastic body (high damping rubber) 33 when the vibration damper 30A is viewed in a plane, and the outer edge portion 31b is fastened to the core material 21A by bolts 40, and the second outer steel plate 32 is joined to the cement-based hardened body 24.
According to this configuration, the first outer steel plate 31A has an outer dimension larger than that of the viscoelastic body (high damping rubber) 33, so that the outer edge portion 31b protrudes outward from the viscoelastic body (high damping rubber) 33. The vibration damper 30A can be joined to the core material 21A by fastening the outer edge portion 31b to the core material 21A with the bolts 40. Moreover, the vibration damper 30A is joined to the cementitious hardened body 24 by joining the second outer steel plate 32 to the cementitious hardened body 24. In this way, it is possible to configure the viscoelastic body 33 to damp the relative movement between the core material 21A and the outer steel pipe 22A.

(Modification of the first embodiment)
The brace structure of the present invention is not limited to the first embodiment described above with reference to the drawings, and various modifications are possible within the technical scope of the present invention.
For example, in the above embodiment, the outer steel pipe 22A is made of a circular steel pipe having a circular cross-sectional shape perpendicular to the axial direction Da, but this is not limited to the above.
FIG. 4 is a cross-sectional view showing the configuration of a modified example of the brace structure according to the first embodiment of the present invention.
As shown in Fig. 4, the outer steel pipes 22B constituting the brace structure 10A may be made of, for example, square steel pipes having a rectangular cross-sectional shape perpendicular to the axial direction Da of the brace structure 10A. In this case, the outer steel pipes 22B are provided so that their corner portions 22p are located outside each plate-shaped portion 21p of the core material 21A having a cruciform cross section.
FIG. 5 is a cross-sectional view showing the configuration of another modified example of the brace structure according to the first embodiment of the present invention.
As shown in Figure 5, a brace structure 10A is formed by an outer steel pipe 22C made of a square steel pipe having a rectangular cross-sectional shape perpendicular to the axial direction Da, and the outer steel pipe 22C may be arranged so that its four flat portions 22q are located outside each plate-shaped portion 21p of a core material 21A having a cross-shaped cross section.

[Second embodiment]
Next, a brace structure according to a second embodiment of the present invention will be described.
The second embodiment described below differs from the first embodiment in that, whereas the core material 21A in the first embodiment has a cross-shaped cross section, the core material 21B in the second embodiment has a composite cross section (H-shaped cross section) in which C-shaped steel materials are placed back to back. In the following description, the same reference numerals are used in the drawings to designate components common to the first embodiment, and detailed description thereof will be omitted.

FIG. 6 is a cross-sectional view showing the configuration of a brace structure according to a second embodiment of the present invention.
As shown in FIG. 6, a brace structure 10B in this embodiment mainly includes a core material 21B, an outer steel pipe 22C, and a vibration damper 30B.
In this embodiment, the core material 21B has a cross-sectional shape perpendicular to the axial direction Da (see FIG. 1) of the brace structure 10B, which is a composite cross-section (H-shaped cross-section) in which the C-shaped steel materials 25 are placed back to back. Specifically, the C-shaped steel materials 25 constituting the core material 21B each have a web 25a and a pair of flanges 25b. The web 25a is formed along a plane including the axial direction Da (direction perpendicular to the paper surface of FIG. 6) and a first direction D1 perpendicular to the axial direction Da. The pair of flanges 25b extend from both ends of the web 25a in the first direction D1 in parallel to a second direction D2 perpendicular to the axial direction Da and the first direction D1. As a result, the C-shaped steel material 25 has a cross-sectional C-shape when viewed from the axial direction Da. In the core material 21B, the webs 25a of the pair of C-shaped steel materials 25 are arranged overlapping each other in the second direction D2. The core material 21B is configured such that the flanges 25b of a pair of C-shaped steel materials 25 protrude from the overlapping webs 25a on both sides in the second direction D2. In other words, the directions in which the pair of flanges 25b extend from the webs 25a of one C-shaped steel material 25 and the other C-shaped steel material 25 are different from each other. In this way, the core material 21B has a composite cross section in which the webs 25a of the C-shaped steel materials 25 are overlapped and placed back to back. As a result, the core material 21B is formed so that its cross-sectional shape is H-shaped overall.
The cement-based hardened body 24 provided on the inside of the outer steel pipe 22C is joined only to the second outer steel plate 32 in relation to the vibration damper 30B described later, and is provided with a gap S2 between it and the core material 21B, the viscoelastic body 33 of the vibration damper 30B, and the first outer steel plate 31B.

In this embodiment, the vibration dampers 30B are disposed on each of the pair of C-shaped steel materials 25 constituting the core material 21B. The vibration dampers 30B are disposed on both sides of the webs (plate-shaped portions) 25a of the pair of C-shaped steel materials 25. Each vibration damper 30B includes a first outer steel plate 31B, a second outer steel plate 32, and a viscoelastic body 33. The vibration dampers 30B are configured by laminating the first outer steel plate 31B, the second outer steel plate 32, and the viscoelastic body 33.
The vibration damper 30B is disposed with the first outer steel plate 31B aligned along the web 25a of the C-shaped steel material 25. The vibration damper 30B is housed between a pair of flanges 25b of the C-shaped steel material 25. In other words, the vibration damper 30B is disposed in a portion surrounded by the web 25a of the C-shaped steel material 25 and the pair of flanges 25b.

The first outer steel plate 31B is formed so as to have an outer dimension larger than that of the viscoelastic body 33 when the vibration damper 30B is viewed in a plan view from the stacking direction Ds of the first outer steel plate 31B, the second outer steel plate 32, and the viscoelastic body 33. The first outer steel plate 31B is integral with outer edge portions 31d extending beyond the viscoelastic body 33 on both sides in the first direction D1.
The outer edge portion 31d is fastened to the core material 21B by bolts 40 and nuts 41. In this embodiment, the first outer steel plates 31B of the two vibration dampers 30B arranged on both sides with the web 25a in between are fastened to each other by bolts 40 that penetrate the outer edge portions 31d and the webs 25a of both vibration dampers 30B and nuts 41. In other words, the bolts 40 and nuts 41 are shared by the two vibration dampers 30B arranged on both sides with the webs (plate-shaped portions) 25a of the pair of C-shaped steel materials 25 in between.
The second outer steel plate 32 is integrally provided with a plurality of stud bolts 34. The second outer steel plate 32 is in contact with the cement-based hardened body 24 and is fixed to the cement-based hardened body 24. The plurality of stud bolts 34 are embedded in the cement-based hardened body 24.
In this embodiment, the viscoelastic body 33 is a high-damping rubber having a higher damping performance than normal rubber, similarly to the first embodiment.

The brace structure 10B as described above has a built-in vibration damper 30B and comprises a core material 21B, an outer steel pipe 22C which is arranged to be able to move relative to the core material 21B and has a cement-based hardened body 24 on its inside side, and a vibration damper 30B which is joined to the core material 21B and the cement-based hardened body 24 and has a viscoelastic body (high damping rubber) 33 that damps the relative movement between the core material 21B and the outer steel pipe 22C, and the vibration damper 30B and core material 21B are fastened together with bolts 40.
According to this configuration, the viscoelastic body 33 of the vibration damper 30B is a high-damping rubber having high damping performance. This improves the damping performance of the vibration damper 30B. Furthermore, high-damping rubber has a smaller temperature dependency than normal rubber, and the damping performance is less likely to decrease even if the temperature rises due to external factors such as air temperature and direct sunlight, or due to the absorption of vibration energy. In this way, by using high-damping rubber for the viscoelastic body 33 of the vibration damper 30B realized as a so-called viscoelastic damper, it is possible to improve the damping performance and achieve a configuration that can stably exhibit the damping performance.
Since the damping performance can be improved efficiently in this manner, the total amount of the viscoelastic body 33 required to realize the damping performance required for the vibration damper 30B is reduced. Therefore, it is possible to reduce the length of the vibration damper 30B in the axial direction Da of the brace structure 10B and suppress an increase in size.
Here, while it is not easy to adhere such high-damping rubber to steel materials at construction sites and the like, in the brace structure 10B described above, the vibration damper 30B formed with high-damping rubber is constructed by fastening it to the core material 21B with bolts 40, making it easy to assemble and install at the construction site.
In this way, it is possible to provide a brace structure 10B that is capable of exerting a high damping force while suppressing an increase in size.

In addition, the core material 21B has an H-shaped cross-section, and has a plate-shaped portion 25a, with vibration dampers 30B provided on both sides of the plate-shaped portion 25a, and each of the vibration dampers 30B and the plate-shaped portion 25a are joined by bolts 40 that pass through them.
According to this configuration, the vibration dampers 30B can be incorporated on both sides of the plate-like portion 25a inside the C-shaped steel material 25 that constitutes the H-shaped cross section. In this way, it is possible to provide a plurality of vibration dampers 30B in a limited space, and it is possible to exert a high damping force while suppressing an increase in the size of the brace structure 10B.
Furthermore, when the core material 21B is a steel pipe or the like and has a portion with an annular cross-sectional shape, assembly and construction are not easy because it is necessary to insert a hand from the end of the core material 21B in the axial direction Da into the inside of the annular portion when fastening the vibration damper 30B to the surface of the core material 21B with the bolt 40. In contrast, in the above-mentioned configuration, the core material 21B does not have a portion with an annular cross-sectional shape and is structured so that all surfaces of the core material 21B can be easily contacted from the outside, so that the vibration damper 30B can be easily fastened to the surface of the core material 21B with the bolt 40.
Furthermore, vibration dampers 30B are provided on both sides of the plate-like portion 25a constituting the core material 21B, and each of the vibration dampers 30B and the plate-like portion 25a are joined by a bolt 40 that penetrates them. In other words, since a plurality of vibration dampers 30B can be fastened together to the core material 21B with one bolt 40, the number of bolts 40 used can be reduced and the size of the brace structure 10B can be further prevented from increasing, compared to the case where each vibration damper 30B is fastened to the core material 21B with a bolt 40.

In addition, the vibration damper 30B comprises a first outer steel plate 31B and a second outer steel plate 32 which are provided on opposite sides of the viscoelastic body (high damping rubber) 33, and the first outer steel plate 31B has an outer edge portion 31d formed so that its outer dimensions are larger than those of the viscoelastic body (high damping rubber) 33 when the vibration damper 30B is viewed in a plane, and the outer edge portion 31d is fastened to the core material 21B by bolts 40, and the second outer steel plate 32 is joined to the cement-based hardened body 24.
According to this configuration, the first outer steel plate 31B has a larger outer dimension than the viscoelastic body (high damping rubber) 33, so that the outer edge 31d protrudes outward from the viscoelastic body (high damping rubber) 33. The vibration damper 30B can be joined to the core material 21B by fastening the outer edge 31d to the core material 21B with the bolts 40. Moreover, the vibration damper 30B is joined to the cementitious hardened body 24 by joining the second outer steel plate 32 to the cementitious hardened body 24. In this way, it is possible to configure the viscoelastic body 33 to damp the relative movement between the core material 21B and the outer steel pipe 22B.

(Other Modifications)
In the first and second embodiments, the vibration dampers 30A, 30B are provided over the entire area (total length) where the core materials 21A, 21B and the outer steel pipes 22A to 22C overlap in the axial direction Da, but this is not limited to the above. The vibration dampers 30A, 30B may be provided only in a part of the area where the core materials 21A, 21B and the outer steel pipes 22A to 22C overlap in the axial direction Da. Furthermore, a plurality of vibration dampers 30A, 30B may be provided at intervals in the axial direction Da in the area where the core materials 21A, 21B and the outer steel pipes 22A to 22C overlap in the axial direction Da.
Furthermore, the brace structures 10A, 10B are provided with vibration dampers 30A, 30B between the core materials 21A, 21B and the outer steel pipes 22A to 22C to damp the relative movement between the core materials 21A, 21B and the outer steel pipes 22A to 22C, but other damping mechanisms may be provided in addition to the vibration dampers 30A, 30B. For example, in addition to the vibration dampers 30A, 30B, a configuration may be provided in which a sliding mechanism and an elastic spring are provided in series, and a buckling restraint member that restrains the buckling of the core materials 21A, 21B is further provided as an elastic-plastic damper.
In the second embodiment, the C-shaped steel members 25 are placed back to back to form the core member 21B having an overall H-shaped cross section, but this is not limited to the above. For example, when constructing the vibration damper 30B as described as the second embodiment, an H-shaped steel member may be used as the core member 21B.
Alternatively, the core material does not have to have a cross-shaped or H-shaped cross section, but only needs to have a cross-sectional shape that allows the vibration damper to be easily fastened with a bolt.
In addition, the configurations described in the above embodiments can be selected or changed as appropriate without departing from the spirit of the present invention.

10A, 10B Brace structure 30A, 30B Vibration damper 21A, 21B Core material 31A, 31B First outer steel plate 21p Plate-shaped portion 31b, 31d Outer edge portion 22A to 22C Outer steel pipe 32 Second outer steel plate 24 Cement-based hardened body 33 Viscoelastic body (high damping rubber)
25 C-shaped steel material 40 Bolt 25a Web (plate-shaped portion)

Claims (1)

A brace structure with a built-in vibration damper,
A core material;
An outer steel pipe having a cement-based hardened body provided on an inner side thereof, the outer steel pipe being provided so as to be movable relative to the core material;
a vibration damper which is joined to the core material and the cement-based hardened body and has high damping rubber that damps relative movement between the core material and the outer steel pipe;
The vibration damper includes a first outer steel plate and a second outer steel plate provided on opposite sides of the high damping rubber, and the high damping rubber, the first outer steel plate, and the second outer steel plate are laminated and vulcanized/bonded to each other to form a unit.
the first outer steel plate has an outer edge portion formed so as to protrude outward from the side surface of the high damping rubber, the outer edge portion and the core material are fastened with bolts, and the second outer steel plate is joined to the cement-based hardened body ,
The core material has a cross-shaped cross section,
The core material includes four plate-like portions extending in all directions from a central portion of the cross section when viewed in a cross section perpendicular to the axial direction,
A plurality of the vibration dampers are provided, and in each of the plurality of vibration dampers, a pair of the outer edge portions are provided with the high damping rubber therebetween, and each of the pair of the outer edge portions is provided so as to incline toward the second outer steel plate,
The vibration dampers are disposed between the adjacent plate-like portions in the circumferential direction around the central portion of the cross section of the core material such that each of the pair of outer edge portions is provided along each of the adjacent plate-like portions in the circumferential direction, so that the vibration dampers are provided on both sides of each of the plurality of plate-like portions,
A brace structure characterized in that, in each of the plate-shaped portions, the first outer steel plates of each of the vibration dampers arranged on both sides of the plate-shaped portion are fastened to each other by the bolts that penetrate the plate-shaped portion and each of the outer edge portions provided along the plate-shaped portion .

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