Buckling Restrained Brace

Abstract

To provide a buckling restriction brace capable of demonstrating a vibration control action as designed, by avoiding the occurrence of a part with the thickness of an unbonded material being different from the designed thickness.SOLUTION: A buckling restriction brace 1 comprises a core material 11 having a joint part 11b at both ends of a plate-like part 11a for jointing with another member, restriction materials 12 arranged facing each face orthogonal to the weak axis direction of the plate-like part 11a, and an unbonded material arranged between the core material 11 and the restriction materials 12. The unbonded material comprises multiple tape-like unbonded materials 14. The multiple tape-like unbonded materials 14 are bonded in the short side direction of the core material 11 with gaps G with each other.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] This invention relates to a buckling restraint brace that is incorporated into a structure to absorb vibration energy and dampen vibration during an earthquake or the like. [Background technology]

[0002] Patent Document 1 discloses a buckling restrained brace that includes a core material having joints at both ends of a plate-shaped portion for joining to other members, and restraining materials arranged opposite each face of the plate-shaped portion perpendicular to the weak axis direction, in which an insert plate is provided between the plate-shaped portion and the restraining material in contact with the restraining material, and an unbonded material is positioned between the insert plate and the core material. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-117995 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, in such a buckling restraint brace, the process of providing the unbonded material to, for example, the core material involves attaching a plurality of unbonded materials narrower than the core material.

[0005] However, when the multiple unbonded materials are bonded together, if the multiple unbonded materials overlap, the thickness of the unbonded material at the overlapping portion will be different from that at other portions, and the manufactured buckling restrained brace may not perform as designed. Here, the unbonded material functions as a clearance that allows the core material to deform in a wavy manner when an impact is applied to the buckling restrained brace, and also has the function of reducing friction with the restraining material during this deformation.

[0006] In view of the above circumstances, an object of the present invention is to prevent the occurrence of locations where the thickness of the unbonded material differs from the designed thickness, and to enable the buckling restraint brace to exert the vibration control effect as designed. [Means for solving the problem]

[0007] The buckling restraint brace of the present invention is a buckling restraint brace comprising a core material having joints at both ends of a plate-shaped portion for joining to other members, restraint materials arranged opposite each face perpendicular to the weak axis direction of the plate-shaped portion, and unbonded materials arranged between the core material and the restraint materials, characterized in that the unbonded materials are made up of a plurality of unbonded materials, and the plurality of unbonded materials are affixed with gaps between them in the short side direction of the core material.

[0008] With the above configuration, even if the unbonded material is not attached linearly in the process of attaching it to the core material, causing some distortion, the unbonded material is attached with a gap between them in the short side direction of the core material, so that overlapping of the unbonded material can be avoided. This prevents the thickness of the unbonded material from differing from the design thickness in places, and allows the buckling restraint brace to exert the vibration control effect as designed.

[0009] In addition, even if there is a gap, the unbonded material can function as a clearance that allows the core material to undergo wavy deformation when an impact is applied to the buckling restraint brace, so that the performance can be comparable to that of a configuration without a gap. Furthermore, when the impact causes wavy deformation in the core material, the unbonded material is pushed by the peak of the wavy deformation of the core material and partially pushed out toward the gap, so that friction between the members at the gap is reduced and deformation of the core material can be promoted.

[0010] The unbonded material may be located at the end of the core material in the short side direction. If the unbonded material is attached only to the center of the core material, for example, when the restraining material is placed on the unbonded material in a subsequent process, the restraining material may become unstable like a balance, and the clearance to be secured by the unbonded material may not be the designed value. By positioning the unbonded material at the end of the short side direction of the core material, such clearance problems can be avoided.

[0011] The unbonded material may be attached to the restraining material so as to occupy an area of ​​20% to 95% of the effective width in the short side direction of the restraining material. By reducing the ratio of the unbonded material to the effective width in the short side direction of the restraining material, the amount of the unbonded material used can be reduced, thereby reducing costs.

[0012] An insert plate may be disposed between the core material and the restraining material, and the unbonded material may be located between the insert plate and the core material. Effect of the Invention

[0013] The present invention has the effect of preventing the occurrence of locations where the thickness of the unbonded material differs from the designed thickness, and enabling the buckling restraint brace to exert the vibration control effect as designed. [Brief description of the drawings]

[0014] [Figure 1] 1A and 1B are schematic longitudinal cross-sectional views showing a buckling restraint brace according to an embodiment, in which FIG. 1A shows the completed state and FIG. 1B shows the disassembled state. [Diagram 2] 2A is a perspective view showing the buckling restraint brace of FIG. 1, and FIG. 2B is a perspective view showing the core material. [Diagram 3] Figure 3(A) is an explanatory diagram showing how the stiffening force of the core material in the buckling restraint brace of Figure 1 is received by the restraint material and the inner plate, and Figure 3(B) is an explanatory diagram showing the relationship between the deformation of the core material in the weak axis direction and the stiffening force. [Figure 4] 1 is an explanatory diagram showing an effective attachment length of a tape-shaped unbonded material to a restraint material. FIG. [Diagram 5] FIG. 13 is a schematic longitudinal cross-sectional view of an embodiment of a buckling restraint brace with an insert plate in an exploded state. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. As shown in Figures 1(A), 1(B), 2(A), and 2(B), the buckling restrained brace 1 of this embodiment includes a core material 11, restraining materials 12, unbonded materials 14, 14, width-direction stiffeners 15, and a reinforcing plate 16. In this embodiment, the unbonded material 14 is in the form of a tape, but a sheet-like or plate-like unbonded material can also be used.

[0016] The core material 11 is made of, for example, a steel plate, and has joints 11b at both ends of the plate-shaped portion 11a. The plate-shaped portion 11a has a constant width, and the joints 11b at both ends are wider than the plate-shaped portion 11a. The joints 11b have a cross section perpendicular to the longitudinal direction of the plate-shaped portion 11a that is made to be substantially H-shaped, and a splice plate can be placed on the joints 11b to join them to other members. Holes through which bolts for the above-mentioned joining are inserted are formed in the portions of the joints 11b that will become the flanges and webs. In the boundary region from the plate-shaped portion 11a to the joints 11b, the width of the plate-shaped portion 11a gradually widens in a curved shape, changing in shape to form the webs of the joints 11b.

[0017] The restraining member 12 is made of a square steel pipe with a rectangular cross section. This square steel pipe has a first surface portion which is the long side of the rectangle, and a second surface portion which is the short side. The first surface portion of the restraining member 12 is arranged so as to face each surface perpendicular to the weak axis direction (thickness direction of the core material 11) of the plate-shaped portion 11a of the core material 11. Both longitudinal ends of the restraining member 12 extend beyond the curved spreading portion to reach the web portion at the joint portion 11b. The square steel pipe also has corners with radiused regions (curved regions) at the intersections of the respective surfaces.

[0018] Furthermore, pin-shaped anti-slip projections 11c protruding from both sides of core material 11 are provided at the center of the long side direction and the center of the short side direction of core material 11. These anti-slip projections 11c are inserted into holes provided in the first surface portion that is the inside of restraint material 12 when assembling the buckling restrained brace 1. The anti-slip projections 11c are made of steel such as steel rods, and are joined by being inserted into holes provided in core material 11, for example.

[0019] The width-direction stiffener 15 is made of a steel plate and restrains deformation in the width direction (within the structural plane) of the core material 11. This width-direction stiffener 15 is suspended between the second surface portions of the restraining materials 12, 12 and is fixed to the restraining materials 12, 12 by a welded portion 15a. Furthermore, a U-shaped cut portion 15b having an opening on the end side is formed at the end of the width-direction stiffener 15, and an area where the width of the plate-shaped portion 11a gradually widens in a curved shape is located within this cut portion 15b.

[0020] The reinforcing plate 16 is made of a steel plate, and is placed between the flange portions of the joint portion 11b of the core material 11 and is fixed to the flange portions by welding. The reinforcing plate 16 is provided so as to overlap the unstiffened section (the cut portion 15b).

[0021] As shown in Fig. 3(A) and Fig. 3(B), the tape-shaped unbond material 14 is provided between the plate-shaped portion 11a of the core material 11 and the restraining material 12, and when the plate-shaped portion 11a receives a compressive force with the thickness of the unbond material 14 as a clearance, a wavy deformation occurs. The unbond material 14 is made of, for example, butyl rubber. In this embodiment, two tape-shaped unbond materials 14 are arranged. The tape-shaped unbond material 14 may have a length extending to a position just before the portion where the width of the plate-shaped portion 11a gradually widens in a curved shape.

[0022] The two tape-shaped unbonded materials 14, 14 are attached to the core material 11 in the short side direction with a gap G therebetween. The tape-shaped unbonded material 14 is located on the end side of the core material 11 in the short side direction.

[0023] When the tape-shaped unbond material 14 is attached to the restraining material 12, for example, as shown in FIG. 4, the tape-shaped unbond material 14 may be attached so that a part of the tape-shaped unbond material 14 overlaps the rounded area (horizontal length R) of the corner of the restraining material 12. However, the effective width of the attachment is the X-length portion on the flat plate portion excluding the rounded area. Here, the unbond material 14 that overlaps the above-mentioned rounded area is not included in the effective length of the attachment, so the attachment width ratio of the two sheets of unbond material 14 to the effective width of the restraining material 12 of width A (the length of the flat plate portion (A-2R)) is expressed as 2X / (A-2R). The tape-shaped unbond material 14 may also be attached to the core material 11 side. In this case, the above-mentioned X-length portion that is somewhat separated from the end of the core material 11 becomes the effective length of the unbond material 14. Note that the tape-shaped unbond material 14 with release paper attached on one side may be attached to the other side, and the release paper may be left attached.

[0024] In the above-mentioned buckling restrained brace 1, the tape-like unbonded material 14 is attached to occupy an area of ​​20% or more and 95% or less of the effective width in the short side direction of the restraint material 12. In other words, 20%≦2X / (A-2R)≦95%. There may be three or more pieces of tape-like unbonded material 14, and in such a configuration, two or more gaps G are formed. When there are three pieces of tape-like unbonded material 14, the above-mentioned "2X" should be "3X". It should be noted that the effective width of attachment of the three tape-like unbonded materials 14 is not limited to being the same for all three pieces.

[0025] With the above configuration, even if the tape-like unbonded material 14 is not attached with good linearity and some distortion occurs in the process of attaching the tape-like unbonded material 14 to the core material 11 or the restraining material 12, the tape-like unbonded materials 14 are attached in the short side direction of the core material 11 with gaps G between them, so it is possible to avoid overlapping of the tape-like unbonded materials 14. This makes it possible to prevent the thickness of the unbonded region from differing from the design thickness in places, and allows the buckling restrained brace 1 to exert the vibration control effect as designed.

[0026] Even though the tape-like unbonded material 14 has the above-mentioned gap G, it can function as a clearance that allows the core material 11 to undergo wavy deformation when an impact is applied to the buckling restrained brace 1, and therefore can exhibit performance comparable to that of a configuration without gap G. Note that when two pieces of tape-like unbonded material 14 were positioned on the ends of the core material 11 and a gap G was formed between them, and a test was conducted with 2X / (A-2R) = 20%, performance (hysteresis curve) comparable to that of a configuration without gap G was confirmed, and it can be inferred that performance comparable to that of a configuration without gap G exists even when 20% < 2X / (A-2R).

[0027] In addition, when the core material 11 is deformed in a wavy manner by the impact, the tape-shaped unbond material 14 is pushed by the peaks of the wavy deformation of the core material 11 and is partially pushed out toward the gap G, thereby reducing friction between the members at the gap G and promoting the deformation of the core material 11. The pushing out of the tape-shaped unbond material 14 toward the gap G was also confirmed by testing.

[0028] Here, if the tape-shaped unbond material 14 is attached only to the center of the core material 11, for example, when the restraining material 12 is placed on the tape-shaped unbond material 14 as a subsequent process, the restraining material 12 placed thereon may become unstable like a balance, and the clearance that the unbond material 14 is intended to secure may not be the designed value. In contrast, if the tape-shaped unbond material 14 is positioned on the end side of the short side direction of the core material 11, such a problem can be avoided. Note that even in a structure in which the tape-shaped unbond material 14 is attached only to the center of the core material 11, it is possible to secure the designed clearance by welding the restraining material 12 and the width-direction stiffener 15 to each other via a removable spacer on the end side of the core material 11.

[0029] Furthermore, as described above, the tape-like unbonded material 14 can be reduced to 20% of the effective width in the short side direction of the restraint material 12, thereby reducing the cost of the buckling restraint brace 1.

[0030] The tape-shaped unbonded material 14 does not necessarily have to be disposed between the core material 11 and the restraining material 12. In another embodiment of a buckling restrained brace 1A shown in Fig. 5, an insert plate 13 is disposed between the core material 11 and the restraining material 12, and a tape-shaped unbonded material 14 is located between the insert plate 13 and the core material 11. The tape-shaped unbonded material 14 is attached to the surface of the core material 11 or the insert plate 13 that faces the core material 11. The insert plate 13 is fixed to the restraining material 12 by welding.

[0031] Furthermore, the restraining material 12 is not limited to steel pipes, but may be, for example, a channel steel material filled with mortar or concrete. Furthermore, the joint 11b of the core material 11 is not limited to an H-shape, but may be a cross shape or the like.

[0032] Although the embodiment of the present invention has been described above with reference to the drawings, the present invention is not limited to the illustrated embodiment. Various modifications and variations can be made to the illustrated embodiment within the same scope as the present invention or within an equivalent scope. [Explanation of symbols]

[0033] 1: Buckling restraint brace 1A: Buckling restraint brace 11: Core material 11a: Plate-shaped part 11b: Joint 11c: Anti-slip protrusion 12:Restraint material 13: Interpolation board 14: Unbonded material 15: Width stiffener 15a: Welded section 15b: Cutting section 16: Reinforcement plate G: Gap

Claims

1. A buckling restraint brace comprising a core material having joints at both ends of a plate-shaped portion for joining to other members, restraint materials arranged opposite planar regions which are each surface perpendicular to the weak axis direction of the plate-shaped portion, and unbonded materials arranged between the planar regions and the restraint materials, wherein a plurality of unbonded materials are affixed to the planar region where a single piece of unbonded material can be affixed with gaps between them in the short side direction of the planar region.

2. 2. The buckling restrained brace according to claim 1, wherein the unbonded material is located on an end side of the core material in a short side direction.

3. 3. A buckling restraint brace as described in claim 1 or claim 2, characterized in that the unbonded material is attached to occupy an area of ​​20% or more and 95% or less of the effective width of the restraint material in the short side direction.

4. A buckling restraint brace as described in any one of claims 1 to 3, characterized in that an insert plate is arranged between the core material and the restraint material, and the unbonded material is located between the insert plate and the core material.

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