Buckling-restrained brace

Abstract

To provide a buckling-restrained brace that can suppress interference between the core material, the outer spacer, and the stiffening material when relative displacement occurs between the core material and the outer spacer and stiffening material during an earthquake. [Solution] The system comprises a core material 10 made of a steel plate, a pair of steel restraining members 30 arranged to face the two wide surfaces 11 of the core material 10, a pair of stiffening members 40 joined to both sides of the pair of restraining members 30 on the side of the core material 10 and extending in the longitudinal direction of the core material 10, and a pair of outer spacers 45 extending in the longitudinal direction of the stiffening members 40, with the length of the outer spacers 45 being shorter than the length of the stiffening members 40 in the longitudinal direction, and a first gap G1 being provided between the inner surface 41 of the end 43 of the stiffening member 40 and the narrow surface 12 of the core material 10.

Description

Technical Field

[0001] The present invention relates to a buckling restraint brace.

Background Art

[0002] Conventionally, as braces for forming building structures (column-beam structures, roof structures, etc.), buckling restraint braces with buckling prevention measures have been applied. As buckling restraint braces, there are various bracing forms, such as a form in which the periphery of a steel core material is braced only with steel plates, a form in which the periphery of a steel core material is braced with RC (Reinforced Concrete), and a form in which the periphery of a steel core material is coated with steel and mortar.

[0003] For example, in the buckling restraint brace described in Patent Document 1, an intermediate slit for strength adjustment is provided in the core material, and an internal deformation prevention material made of steel material serving as a spacer is inserted into the intermediate slit so as to be relatively movable in the longitudinal direction. The spacer inserted into the slit provided inside the core material in this way can be called a so-called internal spacer.

[0004] In the core material of the above form, laser cutting is applied when providing a slit into which the internal spacer is inserted in the core material, but there is a problem that the manufacturing yield of the core material is reduced by the laser cutting. Therefore, instead of the form in which a slit is provided in the core material and the internal spacer is inserted, a buckling restraint brace in which a so-called external spacer is disposed on the side surface of the core material has been proposed in Patent Document 2. By installing the external spacer, the gap (clearance) between the width in the strong axis direction of the core material and the width of the restraint material that restrains the core material can be managed to a predetermined value.

[0005] The buckling-restrained brace (here, buckling-restrained building material) described in Patent Document 2 is a buckling-restrained building material in which a core material is sandwiched between two buckling-restrained members. A gap-holding member is interposed between the two buckling-restrained members on the longitudinal side of the core material to secure a predetermined amount of gap between the core material and the core material-facing surfaces of the two buckling-restrained members. A displacement-suppressing member is positioned on the longitudinal side of the core material to suppress lateral displacement of the core material. The gap-holding member consists of a displacement-suppressing member and a gap-adjusting member interposed between the gap-holding member-facing surface of at least one of the two buckling-restrained members and the displacement-suppressing member. The gap-adjusting member is a low-strength member with lower strength than the core material. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Patent No. 6445862 [Patent Document 2] Patent No. 6644370 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] In the buckling-restrained brace (buckling-restrained building material) described in Patent Document 2, a gap-holding member equivalent to an external spacer is provided inside the buckling-restrained member, and the longitudinal lengths of both are set to be the same. Therefore, when the structural surface to which the buckling-restrained brace is attached deforms during an earthquake, and the core material constituting the buckling-restrained brace expands and contracts or compresses in its longitudinal direction, a relative displacement occurs between the buckling-restrained member and the gap-holding member, and there is a risk that the two will interfere with each other.

[0008] The present invention has been made in view of the above problems, and relates to a buckling-restrained brace in which a pair of stiffening members are joined to a pair of restraining members facing the wide surface of a core member, and an external spacer is provided between the core member and the stiffening members, with the objective of providing a buckling-restrained brace that can suppress interference between the core member, the external spacer and the stiffening members when relative displacement occurs between the core member and the external spacer and the stiffening members during an earthquake. [Means for solving the problem]

[0009] To achieve the above objective, one embodiment of the buckling-restrained brace according to the present invention is: A core made of steel plate, A pair of steel restraining members are arranged to face the two wide surfaces of the aforementioned core material, On the side of the core material, a pair of stiffening members are joined to both sides of the pair of restraining members and extend in the longitudinal direction of the core material, The stiffening member comprises a pair of outer spacers extending in the longitudinal direction, located on the narrow side of the core material. The longitudinal length of the outer spacer is set to be shorter than the longitudinal length of the stiffening material. A first gap is provided between the inner surface of the end of the stiffening material and the narrow surface of the core material.

[0010] According to this embodiment, in a buckling-restrained brace in which a pair of stiffening members are joined to a pair of restraining members facing the wide surface of a core member, and an outer spacer is provided between the core member and the stiffening members, the longitudinal length of the outer spacer is set to be shorter than the longitudinal length of the stiffening member, and a first gap is provided between the inner surface of the end of the stiffening member and the narrow surface of the core member. As a result, when relative displacement occurs between the core member and the outer spacer and stiffening member during an earthquake, interference between the core member and the stiffening member can be suppressed by the first gap, and interference between the core member and the outer spacer can be suppressed because the outer spacer is shorter than the stiffening member.

[0011] Furthermore, since there is no need for slits to accommodate internal spacers within the core material, it is no longer necessary to process the core material with laser cutting or other methods, which significantly improves the manufacturing yield of the core material and thus improves the manufacturability of the buckling-restrained brace.

[0012] Here, the extent to which the longitudinal length of the outer spacer should be shortened relative to the longitudinal length of the stiffener, and the extent to which the first gap should be set, will be determined based on the amount of deformation (compression and elongation) of the core material when the frame deforms due to the set seismic force, and the relative displacement between the ends of the core material and the outer spacer and stiffener, respectively. The first gap and the distance between the ends of the stiffener and the outer spacer (relative distance between the ends) will be set accordingly. For example, the first gap can be set after setting the relative distance between the ends of the stiffener and the ends of the outer spacer to about half of the design elongation of the core material.

[0013] Furthermore, the core material to be applied may be formed from a steel plate with a constant width in the longitudinal direction, or it may be formed from a constricted steel plate having a narrow section in the center and wider sections at both ends of the narrow section.

[0014] Furthermore, other embodiments of the buckling-restrained brace according to the present invention include: The stiffening material and the outer spacer are characterized by being integrally molded.

[0015] According to this embodiment, since the stiffener and the outer spacer are integrally molded, the manufacturing efficiency of both the stiffener and the outer spacer can be increased. Furthermore, because the stiffener and the outer spacer are integrally molded, there is no risk of them separating due to displacement or other reasons when an external force is applied, which could lead to problems such as both becoming ineffective.

[0016] Furthermore, other embodiments of the buckling-restrained brace according to the present invention include: The stiffening material and the outer spacer are formed separately and joined together by welding.

[0017] According to this embodiment, since the stiffening material and the outer spacer are molded separately and firmly joined by welding, there is no risk of them separating due to displacement or other reasons when an external force is applied, resulting in both becoming unable to function properly.

[0018] In addition, another aspect of the buckling restraint brace according to the present invention is that a second gap is set between the restraint member and the wide surface of the core material, a third gap is set between the narrow surface of the core material and the outer spacer, and the outer spacer abuts against the ends of the pair of restraint members, thereby ensuring the second gap and the third gap.

[0019] According to this aspect, since a second gap is set between the restraint member and the wide surface of the core material, and a third gap is set between the narrow surface of the core material and the outer spacer, it is possible to prevent the deformation of the core material in the weak axis direction from being suppressed while preventing the buckling of the core material in the weak axis direction by the second gap, and to prevent the deformation of the core material in the strong axis direction from being suppressed while preventing the buckling of the core material in the strong axis direction by the third gap. Further, since the outer spacer abuts against the ends of the pair of restraint members, both the second gap and the third gap can be ensured, and it can be ensured that the above effects by the second gap and the third gap are achieved.

[0020] In addition, another aspect of the buckling restraint brace according to the present invention is that on two wide surfaces of the core material, reinforcing fins extending in a direction orthogonal to the wide surface are welded and joined over a predetermined range in the longitudinal direction of the core material from their respective ends.

[0021] According to this aspect, since reinforcing fins are provided over a predetermined range in the longitudinal direction of the core material from their respective ends on two wide surfaces of the core material, the ends of the core material joined to brackets or the like of the structure can be effectively reinforced. Here, an end plate extending in a direction orthogonal to the longitudinal direction is welded and joined to the longitudinal end of the core material, and the bracket of the structure and the end plate can be bolted or the like to each other.

[0022] In addition, another aspect of the buckling restraint brace according to the present invention is that At a position corresponding to the core material of the supplementary stiffening material, a first slit is provided over a predetermined range in the longitudinal direction from the end of the supplementary stiffening material, and a closing plate for closing the first slit is attached to the outer surface of the supplementary stiffening material. A fourth gap is provided between the narrow-width surface of the core material and the inner surface of the closing plate.

[0023] According to this aspect, a first slit is provided at a position corresponding to the core material of the supplementary stiffening material, a closing plate for closing the first slit is attached to the outer surface of the supplementary stiffening material, and a fourth gap larger than the first gap described above is provided between the narrow-width surface of the core material and the inner surface of the closing plate, so that interference between the core material and the supplementary stiffening material can be suppressed by the fourth gap.

[0024] Here, "a first slit is provided over a predetermined range in the longitudinal direction from the end of the supplementary stiffening material" means, for example, setting a predetermined range as the range within which the deformed core material can contact the supplementary stiffening material based on the deformation mode in the plane of the end of the core material during a major earthquake, and providing the first slit within this range.

[0025] Another aspect of the buckling restraint brace according to the present invention is At a position corresponding to the core material of the supplementary stiffening material, a convex portion protruding outward is provided over a predetermined range in the longitudinal direction from the end of the supplementary stiffening material. A fourth gap is provided between the narrow-width surface of the core material and the inner surface of the convex portion.

[0026] According to this aspect, a convex portion protruding outward is provided at a position corresponding to the core material of the supplementary stiffening material, and a fourth gap larger than the first gap described above is provided between the narrow-width surface of the core material and the inner surface of the convex portion, so that interference between the core material and the supplementary stiffening material can be suppressed by the fourth gap.

[0027] Another aspect of the buckling restraint brace according to the present invention is The restraining member is characterized in that a second slit is provided at a position corresponding to the reinforcing fin to prevent interference with the reinforcing fin, with a fifth gap between it and the reinforcing fin.

[0028] According to this embodiment, a second slit is provided in the restraining member at a position corresponding to the reinforcing fin, with a fifth gap between the slit and the reinforcing fin, thereby effectively preventing interference between the reinforcing fin and the end region of the restraining member when the reinforcing fin is long and interference between the reinforcing fin and the end region of the restraining member is possible. Here, the fifth gap between the reinforcing fin and the end face of the second slit is set to a width such that the reinforcing fin and the second slit do not come into contact when the core material deforms, for example, during a major earthquake. [Effects of the Invention]

[0029] As can be understood from the above explanation, the buckling-restrained brace of the present invention is characterized in that a pair of stiffening members are joined to a pair of restraining members facing the wide surface of the core member, and an external spacer is provided between the core member and the stiffening members. In this buckling-restrained brace, interference between the core member, the external spacer and the stiffening members can be suppressed when relative displacement occurs between the core member and the external spacer and the stiffening members during an earthquake. [Brief explanation of the drawing]

[0030] [Figure 1] This is an exploded perspective view of an example of a buckling-restrained brace according to an embodiment. [Figure 2] This is a perspective view of an example of a buckling-restrained brace according to an embodiment. [Figure 3] This is a view along the line III-III in Figure 2. [Figure 4] This is a view from arrow IV-IV in Figure 2. [Figure 5] This is a perspective view of another example of a buckling-restrained brace according to the embodiment. [Figure 6] This is a view from the line VI-VI in Figure 5. [Modes for carrying out the invention]

[0031] The buckling-restrained brace according to the embodiment will be described below with reference to the attached drawings. In this specification and drawings, substantially identical components may be denoted by the same reference numerals to avoid redundant explanations.

[0032] [Buckling-restrained brace according to an embodiment] An example of a buckling-restrained brace according to the embodiment will be described with reference to Figures 1 to 6. Here, Figure 1 is an exploded perspective view of an example of a buckling-restrained brace according to the embodiment, and Figure 2 is a perspective view of an example of a buckling-restrained brace according to the embodiment. Figures 3 and 4 are views taken along arrows III-III and IV-IV in Figure 2, respectively. Furthermore, Figure 5 is a perspective view of another example of a buckling-restrained brace according to the embodiment, and Figure 6 is a view taken along arrow VI-VI in Figure 5.

[0033] As shown in Figure 1, the buckling-restrained brace 100 comprises a core material 10, a pair of steel restraint members 30 arranged opposite to the two wide surfaces 11 of the core material 10, a pair of longitudinally extending stiffeners 40 welded to the upper and lower side surfaces 32 of the pair of restraint members 30 on the side of the core material 10, and a pair of longitudinally extending outer spacers 45 interposed between the narrow surface 12 of the core material 10 and the inner surface 41 of the stiffeners 40.

[0034] The core material 10 is preferably made of steel with a low yield point, such as SN material (rolled steel for building structures) or LYP material (ultra-low yield point steel). By applying a core material 10 made of these materials, the seismic energy absorption performance due to yielding of the core material 10 is improved.

[0035] The core material 10 in the illustrated example has a slender rectangle in plan view, where the width of its wide surface 11 is the same throughout its entire length. However, it may also have a constricted shape with a narrow section in the center and wide sections at both ends.

[0036] At the center of the width direction of the two wide surfaces 11 of the core material 10, reinforcing fins 15 made of steel plates are welded in a direction perpendicular to the wide surfaces 11, extending from the longitudinal ends 13 of each surface to a predetermined range L4 in the longitudinal direction of the core material 10. In the illustrated example, the reinforcing fins 15 have a plan view shape in which the width changes in a stepped manner midway, but they may also have a form with a constant width or a form in which the width changes in two or more steps.

[0037] Reinforcement fins 15 are provided on the two wide surfaces 11 of the end 13 of the core material 10, making the end cross-shaped, thereby ensuring the rigidity of the longitudinal end of the core material 10 (especially the rigidity in the weak axis direction). Therefore, the length of the reinforcement fins 15 (a predetermined range L4) is set to a length that provides the required strength (bending rigidity and shear rigidity) to withstand the sectional forces generated at the end of the core material 10 when the core material 10 deforms during a major earthquake.

[0038] An end plate 17 is welded to the longitudinal end 13 of the core material 10 shown in Figure 1. Here, "welding" in this specification refers to a type of welding that is appropriate for the strength required at the joint and the type of joint, such as groove welding (full penetration welding, partial penetration welding), fillet welding, or laser welding.

[0039] A cylindrical projection 14 made of steel protrudes from the center of the wide surface 11 of the core material 10 in the longitudinal direction. The projection 14 is joined to the wide surface 11 by welding or the like.

[0040] In fabricating the buckling-restrained brace, a steel end plate 17 extending perpendicular to the longitudinal direction is welded to the longitudinal end 13 of the core material 10. The end plate 17 has multiple (two in the illustrated example) bolt holes 17a through which bolts are inserted when the buckling-restrained brace is bolted to a bracket (not shown) attached to the side of a column forming the building frame when the buckling-restrained brace is incorporated into a building frame (not shown).

[0041] The restraining member 30 is formed from a rectangular steel pipe with a rectangular cross-section, and the opposing surface 31 facing the wide surface 11 of the core material 10 is provided with a projection hole 31a into which the projection 14 of the core material 10 fits. Here, the restraining member may be formed from materials other than rectangular steel pipes, such as channel steel or a shaped steel unit formed by assembling two angle steels into a rectangular frame.

[0042] In the restraining member 30, a second slit 33 is provided in a position corresponding to the reinforcing fin 15 attached to the core material 10, extending from the end 34 to a predetermined length L5 to prevent interference with the reinforcing fin 15 when assembling the restraining member 30.

[0043] Furthermore, a gap G0 of a predetermined width is provided between the second slit 33 and the end face of the reinforcing fin 15.

[0044] The width of this gap G0 is set such that, for example, when the core material 10 deforms in the strong axis direction during a major earthquake, the reinforcing fins 15 and the end face of the second slit 33 do not come into contact. This prevents the reinforcing fins 15 from pressing against the end face of the second slit 33 and damaging the end of the restraining member 30 during a major earthquake.

[0045] Furthermore, a fifth gap (not shown) is provided between the tip of the reinforcing fin 15 and the end of the second slit 33. The length L5 of the second slit 33 is set such that, for example, when the core material 10 is compressed by a compressive force during a major earthquake and shrinks in the longitudinal direction, the tip of the reinforcing fin 15 does not come into contact with the second slit 33. This fifth gap also prevents the reinforcing fin 15 from pressing against the end face of the second slit 33 and damaging the end of the restraining member 30 during a major earthquake.

[0046] On each of the opposing surfaces 41 of the pair of stiffeners 40, a steel outer spacer 45 with a length L2 shorter than the longitudinal length L1 of the stiffener 40 is provided at a position facing the narrow surface 12 of the core material 10.

[0047] In this example, the outer spacer 45 is integrally molded with the stiffener 40. By integrally molding the outer spacer 45 and the stiffener 40 in this way, the manufacturing efficiency of both the stiffener 40 and the outer spacer 45 can be increased. Furthermore, because the stiffener 40 and the outer spacer 45 are integrally molded, problems such as them shifting or separating when an external force is applied, causing both to malfunction, do not occur.

[0048] Furthermore, instead of the configuration shown in the illustration in which the outer spacer 45 and the stiffener 40 are integrally molded, the stiffener and the outer spacer may be molded separately and firmly joined together by welding. In this configuration, although the manufacturing efficiency is lower compared to the integrally molded configuration, the problem of the two parts shifting and separating when an external force is applied can be eliminated.

[0049] Furthermore, although the cross-sectional shape of the outer spacer 45 perpendicular to the longitudinal direction in the illustrated example is rectangular (square or rectangle), a polygon or other shape other than a rectangle may be applied to the cross-sectional shape.

[0050] Compared to a configuration in which a slit is provided in the core material and an internal spacer is inserted, the configuration in which an external spacer 45 is arranged on the side of the narrow surface 12 of the core material 10, as shown in the illustrated example, increases the cross-sectional rigidity of the core material 10 in the strong axis direction (because the height of the core material in the strong axis direction decreases by the width of the slit provided in the core material, thus reducing the cross-sectional rigidity), which allows for a larger buckling wavelength in the strong axis direction. This is preferable because it can suppress the increase in load on the compression side during deformation of the narrow surface 12 of the core material 10.

[0051] In the illustrated example, the distance between the end 43 of the stiffener 40 and the end 46 of the outer spacer 45 is half the difference between the longitudinal length L1 of the stiffener 40 and the length L2 of the outer spacer 45 attached to its center, L3.

[0052] The cross-sectional view shown in Figure 3 shows a cross-section perpendicular to the longitudinal direction of the general section on the central side of the buckling-restrained brace 100, and a third gap G3 with length (width) L8 is provided between the narrow surface 12 of the core material 10 and the outer spacer 45.

[0053] On the other hand, as shown in Figures 3 and 4, a second gap G2 with length (width) L7 is provided between the wide surface 11 of the core material 10 and the opposing surface 31 of the restraining material 30.

[0054] The length (width) L7 of the second gap G2 provided between the opposing surface 31 of the restraining member 30 and the wide surface 11 of the core material 10 is set to a width that prevents buckling of the core material 10 in the weak axis direction during a major earthquake, prevents suppression of deformation of the core material 10 in the weak axis direction during a major earthquake, and effectively absorbs earthquake energy.

[0055] On the other hand, the length (width) L8 of the third gap G3 provided between the outer spacer 45 and the narrow surface 12 of the core material 10 is set to a width that prevents buckling of the core material 10 in the strong axis direction during a major earthquake, prevents the deformation of the core material 10 in the strong axis direction during a major earthquake, and effectively absorbs earthquake energy.

[0056] Furthermore, because the length L2 of the outer spacer 45 is set shorter than the longitudinal length L1 of the stiffener 40, as shown in Figure 4, the outer spacer 45 is absent at the end 43 of the stiffener 40, and a first gap G1 with length (width) L6 is provided between the inner surface 41 of the stiffener 40 and the narrow surface 12 of the core material 10.

[0057] In this way, the longitudinal length L2 of the outer spacer 45 is set to be shorter than the longitudinal length L1 of the stiffener 40, and a first gap G1 of length (width) L6 is provided between the inner surface 41 of the end 43 of the stiffener 40 and the narrow surface 12 of the core material 10. As a result, when relative displacement occurs between the core material 10 and the outer spacer 45 and the stiffener 40 during a major earthquake, interference between the narrow surface 12 of the core material 10 and the inner surface 41 of the stiffener 40 can be suppressed by the first gap G1. Furthermore, since the outer spacer 45 is shorter in length than the stiffener 40, as shown in Figure 4, the outer spacer 45 does not exist in the area of ​​the end 43 of the stiffener 40, and interference between the narrow surface 12 of the core material 10 and the outer spacer 45 can also be suppressed.

[0058] Furthermore, as shown in Figure 3, the outer spacer 45 fits into and contacts the ends of the pair of restraining members 30, automatically forming the second gap G2 and the third gap G3, and ensuring the width of these gaps.

[0059] The buckling-restrained brace 100A shown in Figures 5 and 6 differs from the buckling-restrained brace 100 in that a first slit 47 is provided at a position corresponding to the narrow surface 12 of the core material 10 of the stiffener 40A, extending from the end of the stiffener 40A over a predetermined range in its longitudinal direction, and a closing plate 48 that closes the first slit 47 is attached to the outer surface 42 of the stiffener 40A.

[0060] A fourth gap G4 with length (width) L7 is provided between the narrow surface 12 of the core material 10 and the inner surface 49 of the closing plate 48. As is clear when compared with the first gap G1 with length (width) L6 shown in Figure 4, a larger gap can be provided between the narrow surface 12 of the core material 10 and the stiffener 40A (and the closing plate 48 joined to it). Therefore, when relative displacement occurs between the core material 10 and the outer spacer 45 and the stiffener 40A during a major earthquake, interference between the narrow surface 12 of the core material 10 and the closing plate 48 located outside the first slit 47 of the stiffener 40A can be suppressed by the fourth gap G4. Furthermore, since the outer spacer 45 is shorter in length than the stiffener 40A, as shown in Figure 6, the outer spacer 45 does not exist in the area at the end of the stiffener 40A, and interference between the narrow surface 12 of the core material 10 and the outer spacer 45 can also be suppressed.

[0061] Here, although not shown in the diagram, in addition to the configuration in which a first slit is provided in the stiffening member and a closing plate that closes the first slit is attached to the outside, there may also be a configuration in which a protrusion is provided in the stiffening member at a position corresponding to the core material, extending outward from the end of the stiffening member over a predetermined range in the longitudinal direction, and a fourth gap is provided between the narrow surface 12 of the core material 10 and the inner surface of the protrusion.

[0062] Furthermore, other embodiments may be used in which other components are combined with the configurations listed in the above embodiments, and the present invention is not limited in any way to the configurations shown herein. In this regard, modifications can be made without departing from the spirit of the present invention, and can be appropriately determined according to the application form. [Explanation of symbols]

[0063] 10: Core material 11: Wide surface 12: Narrow surface 13: End 14: Protrusion 15: Reinforcement fins 17: End plate 17a: Bolt hole 30: Retaining material (square steel pipe) 31: Opposing surface 32: Side view 33: Second Slit 34: End 40, 40A: Stiffener 41: Inner surface (opposite surface) 42:Outer surface 43: End 45: External spacer 46: End 47: First Slit 48: Occlusion plate 49: Inner surface 100,100A: Buckling-restrained brace G0: Gap G1: First gap G2: Second gap G3: Third gap G4: Fourth gap

Claims

1. A core made of steel plate, A pair of steel restraining members are arranged to face the two wide surfaces of the aforementioned core material, On the side of the core material, a pair of stiffening members are joined to both sides of the pair of restraining members and extend in the longitudinal direction of the core material, The stiffening member comprises a pair of outer spacers extending in the longitudinal direction, located on the narrow side of the core material. The longitudinal length of the outer spacer is set to be shorter than the longitudinal length of the stiffening material. A buckling-restrained brace characterized in that a first gap is provided between the inner surface of the end of the stiffening member and the narrow surface of the core member.

2. The buckling-restrained brace according to claim 1, characterized in that the stiffening member and the outer spacer are integrally molded.

3. The buckling-restrained brace according to claim 1, characterized in that the stiffening member and the outer spacer are molded separately and joined by welding.

4. A second gap is provided between the restraining material and the wide surface of the core material. A third gap is provided between the narrow surface of the core material and the outer spacer. The buckling-restrained brace according to claim 1, characterized in that the external spacer contacts the ends of the pair of restraining members, thereby ensuring the second gap and the third gap.

5. The buckling-restrained brace according to claim 1, characterized in that reinforcing fins are welded to the two wide surfaces of the core material, extending from each end over a predetermined range in the longitudinal direction of the core material in a direction perpendicular to the wide surfaces.

6. A first slit is provided in the stiffener at a position corresponding to the core material, extending from the end of the stiffener over a predetermined range in its longitudinal direction, and a closing plate is attached to the outer surface of the stiffener to close the first slit. The buckling-restrained brace according to claim 1, characterized in that a fourth gap is provided between the narrow surface of the core material and the inner surface of the closing plate.

7. At a position corresponding to the core material of the stiffening material, a protrusion is provided that extends outward from the end of the stiffening material over a predetermined range in its longitudinal direction. The buckling-restrained brace according to claim 1, characterized in that a fourth gap is provided between the narrow surface of the core material and the inner surface of the protrusion.

8. The buckling restraint brace according to claim 5, characterized in that, among the restraint members, a second slit is provided at a position corresponding to the reinforcing fin to prevent interference with the reinforcing fin, with a fifth gap between it and the reinforcing fin.

Images