Buckling-restrained brace

Abstract

To provide a buckling restraint brace which is suitable for use by being incorporated into a frame of a wooden building etc., and which can reduce the number of parts.SOLUTION: A buckling restraint brace 100 includes: a steel plate-shaped core material 10; and a restraint material 20 formed by a pair of wooden restraint plates 21 arranged to face two wide surfaces 11a of the core material 10 and a pair of spacers 25 arranged to face two narrow surfaces 11b of the core material 10 and connected to the pair of restraint plates 21.SELECTED DRAWING: Figure 6

Description

Technical Field

[0005]

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

Background Art

[0002] Conventionally, as braces for forming building frameworks (column-beam frameworks, roof frameworks, 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 covered with steel and mortar.

[0003] By the way, recently, efforts have been made to improve the fire resistance and seismic resistance of wooden buildings (wooden houses, wooden warehouses, wooden stadiums, etc.). Wooden houses inherently have advantages such as a high degree of freedom in floor plans and designs, a soothing effect due to natural wood, a humidity control effect of wood, and generally lower construction costs compared to steel-frame or RC structures depending on the building use such as houses. However, the improvement of the above-mentioned fire resistance and seismic resistance is one of the factors increasing the attention of wooden buildings including wooden houses. When incorporating the above-mentioned conventional buckling restraint braces into the framework of such a wooden house, it is inevitable that wooden columns and beams and buckling restraint braces having metal or concrete bracing materials will coexist, resulting in an unbalanced appearance.

[0004] Therefore, a measure of covering the entire buckling restraint brace with a wooden or paper panel or the like so that the metal or concrete bracing material cannot be visually recognized from the outside can be considered. However, this measure requires a great deal of labor, so an increase in construction costs is a concern. In addition, since conventional buckling restraint braces use a lot of metal, concrete, mortar, etc., they tend to be heavy, and it is structurally unbalanced to attach a heavy buckling restraint brace to lightweight wooden beams and columns that make up a wooden house.

[0005] Here, Patent Document 1 proposes a buckling-restrained brace suitable for use incorporated into the frame of wooden buildings, including wooden houses. Specifically, it is a buckling-restrained brace having a core material and a pair of restraining members arranged along both sides of the core material, in which the core material is made of steel and the pair of restraining members are made of wood, and laminated timber is applied to these restraining members, and the laminated timber has laminations stacked parallel to the core material. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Patent No. 4901491 [Overview of the project] [Problems that the invention aims to solve]

[0007] Conventional buckling-restrained braces consist of a steel core surrounded by a restraining material comprising a pair of restraining plates facing the two wide surfaces of the core, and a pair of side plates connecting the ends of the pair of restraining plates. Furthermore, within the restraining material, a pair of spacers are provided between the core and the pair of side plates. Due to the large number of parts, there is room for improvement in terms of manufacturing effort and cost.

[0008] This invention has been made in view of the above problems, and aims to provide a buckling-restrained brace that is suitable for use incorporated into the frame of wooden buildings and the like, and that can reduce the number of parts. [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 steel, plate-shaped core material, The restraining member is characterized by comprising: a pair of wooden restraining plates arranged to face the two wide surfaces of the core material; and a pair of spacers arranged to face the two narrow surfaces of the core material and connected to the pair of restraining plates.

[0010] According to this embodiment, by configuring the restraint member with a pair of restraint plates and a pair of spacers, the conventional side plates can be eliminated, and the number of parts can be reduced. In addition, the spacers that make up the restraint member also have the function of restraining the core material inside and preventing buckling of the core material in the strong axis direction.

[0011] In this embodiment, most of the restraining material, excluding the spacers, is made of wood and formed by a pair of restraining plates, and a steel core is surrounded by this restraining material. Therefore, even when the buckling-restrained brace of this embodiment is applied to the frame of a wooden building, there is no risk of it appearing inconsistent with the structural members. Here, the restraining plates may be made of solid wood or of laminated timber with laminated laminas. There are no limitations on the material of the spacers, but for example, wooden spacers may be used. In this embodiment, the entire area of ​​the restraining material is made of wood (it becomes a wooden restraining material), which increases the unity of the restraining material and further enhances its appearance and design.

[0012] Furthermore, in this embodiment, since the restraint material is formed by, for example, a pair of plate-shaped restraint plates, the processing of the wooden restraint material becomes easier. For example, the buckling restraint brace described in Patent Document 1 requires processing laminated timber to produce two L-shaped wooden restraint materials, and then connecting them with a core material in between by inverting them. In contrast, the buckling restraint brace of this embodiment can be manufactured by, for example, interposing a core material between a pair of plate-shaped restraint plates and connecting the restraint plates via a pair of spacers, thereby manufacturing the restraint material and the buckling restraint brace at the same time. Therefore, the manufacturing of the buckling restraint brace becomes even easier.

[0013] Furthermore, in other embodiments of the buckling-restrained brace according to the present invention, The core material has a narrow section at its longitudinal center where the width of the wide surface is relatively narrow, and a wide section at its longitudinal end where the width of the wide surface is relatively wide. The pair of spacers are characterized in that they abut against the narrow surface of the narrow portion and have a gap between them and the narrow surface of the wide portion.

[0014] In this embodiment, the core material has a narrow section with a relatively narrow width on the central side in its longitudinal direction, and a wide section with a relatively wide width on the end side in its longitudinal direction. This makes the narrow section on the central side a region that is easily plasticized, and furthermore, the plasticization region can be limited to the narrow section on the central side. In addition, since the boundary region between the wide section and the narrow section is a change region in which the planar area and cross-sectional area of ​​the core material change, the additional bending moment acting on the core material can be absorbed in this change region. An additional bending moment (or simply additional bending) is a bending moment that can act on a restraining member as a result of deformation when the frame and buckling-restrained brace deform significantly, for example, during a major earthquake. Thus, in this embodiment, the additional bending moment acting on the core material can be effectively absorbed in the boundary region between the wide section and the narrow section of the core material.

[0015] While the core material has a wide section and a narrow section, a pair of spacers abut against the narrow surface of the narrow section on the central side of the core material to restrain it, and there is a gap between the spacers and the narrow surface of the wide section on the end side of the core material. This prevents the core material from abutting and being pressed against the ends of the restraining members when the structural surface deforms during an earthquake, thus preventing cracks or damage to the spacers.

[0016] Furthermore, in other embodiments of the buckling-restrained brace according to the present invention, The restraint plate and the spacer are connected by either an adhesive or a axial fixing means.

[0017] According to this embodiment, since the restraint plate and the spacer are connected by either an adhesive or a axial fixing means, a restraint material with high connection strength can be formed with good manufacturability. Here, the axial fixing means includes screws, nails, etc.

[0018] Furthermore, in other embodiments of the buckling-restrained brace according to the present invention, The spacer comprises a plurality of divided spacers, wherein the divided spacers consist of a first divided spacer corresponding to the narrow portion and a second divided spacer corresponding to the wide portion.

[0019] According to this embodiment, the spacer is composed of a first divided spacer corresponding to the narrow portion of the core material and a second divided spacer corresponding to the wide portion of the core material. This eliminates the manufacturing effort of producing spacers while changing their shape to correspond to the narrow and wide portions of the core material. For example, both the first divided spacer and the second divided spacer can be simple rectangular parallelepiped spacers with a rectangular cross-sectional shape (rectangle or square) and different cross-sectional dimensions and lengths.

[0020] Furthermore, in other embodiments of the buckling-restrained brace according to the present invention, The spacer comprises a plurality of divided spacers, characterized in that the divided spacers include a third divided spacer extending from the wide portion to the middle of the narrow portion and a fourth divided spacer corresponding to the central region of the narrow portion.

[0021] According to this embodiment, the spacer is composed of a third divided spacer extending from the wide section to the middle of the narrow section and a fourth divided spacer corresponding to the central region of the wide section, thereby enabling the installation of a continuous spacer from the wide section to the middle of the narrow section of the core material while minimizing the length of the spacer. In the region of the third divided spacer corresponding to the wide section of the core material, there is a gap between it and the core material, and in the region corresponding to the narrow section of the core material, it abuts against the core material and restrains it.

[0022] Another aspect of the buckling restraint brace according to the present invention is that there is a gap between the split spacers.

[0023] According to this aspect, by having a gap between the split spacers, the length and volume of the spacers can be reduced. This gap can be set, for example, near the boundary region between the narrow-width part and the wide-width part of the core material, or in a region within the narrow-width part of the core material where there is no concern about a decrease in the yield strength of the core material even without installing a spacer.

[0024] In another aspect of the buckling restraint brace according to the present invention, the ends of the split spacers are fixed to the restraint plate by axial fixing means.

[0025] According to this aspect, since the ends of the split spacers are fixed to the restraint plate by axial fixing means, for example, when a wooden restraint plate may be locally damaged at the ends of the split spacers, local damage to the restraint plate can be suppressed by the axial fixing means that fixes the restraint plate and the spacer. Here, the axial fixing means includes bolts and the like.

[0026] Another aspect of the buckling restraint brace according to the present invention is that the thickness of the spacer is thinner than the thickness of the core material.

[0027] According to this aspect, since the thickness of the spacer is thinner than the thickness of the core material, in other words, since the thickness of the spacer and the thickness of the core material are not strictly aligned (eliminating the need for strict alignment during manufacturing), the manufacturing time of the spacer can be shortened. Even if the thickness of the spacer is slightly thinner than that of the core material, for example, when the restraint plate and the spacer are fixed by axial fixing means, a pair of wooden restraint plates are displaced relative to each other and joined to the spacer.

[0028] Another aspect of the buckling restraint brace according to the invention is that The spacer is characterized by being formed from one of the following: wood, metal, or fiber reinforcement.

[0029] According to this embodiment, in the case of a spacer made of wood, the entire restraining material is made of wood, forming a restraining material with excellent appearance and design, and in the case of a spacer made of metal or fiber reinforcement material, the rigidity and load-bearing capacity of the spacer can be improved compared to a wooden spacer, and failure of the spacer can be further suppressed. [Effects of the Invention]

[0030] As can be understood from the above explanation, the buckling-restrained brace of the present invention is suitable for use by being incorporated into the frame of wooden buildings and the like, and the number of parts can be reduced. [Brief explanation of the drawing]

[0031] [Figure 1] This is a perspective view of an example of a core material forming a buckling-restrained brace according to the embodiment. [Figure 2] This is an exploded perspective view of an example of a restraint material forming a buckling-restrained brace according to the embodiment. [Figure 3] This is a perspective view of an example of a buckling-restrained brace according to an embodiment. [Figure 4] Figure 3 is a view taken along the line IV-IV, and is a cross-sectional view of an example of the end of a buckling-restrained brace according to the embodiment. [Figure 5] Figure 3 is a view taken along the VV direction arrow, and is a cross-sectional view of an example of the central part of a buckling-restrained brace according to the embodiment. [Figure 6] Figure 3 is a view in the direction of arrow VI, and is a plan view of the buckling-restrained brace according to the embodiment. [Figure 7] This is a plan view of another example of a buckling-restrained brace according to the embodiment. [Figure 8] This is a plan view of yet another example of a buckling-restrained brace according to the embodiment. [Figure 9] This figure shows the buckling-restrained brace according to the embodiment incorporated into the frame of a wooden building or the like. [Figure 10] This figure illustrates the deformation patterns of the frame during a major earthquake and the additional bending moment at the buckling-restrained brace joints caused by the deformation of the frame. [Figure 11] This figure shows the overall buckling curve of the buckling-restrained brace.

[0032] 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. [Modes for carrying out the invention]

[0033] [Buckling-restrained brace according to an embodiment] First, 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 a perspective view of an example of a core material forming a buckling-restrained brace according to the embodiment, and Figure 2 is an exploded perspective view of an example of a restraint material forming a buckling-restrained brace according to the embodiment. Figure 3 is a perspective view of an example of a buckling-restrained brace according to the embodiment, Figure 4 is a cross-sectional view of an example of an end of the buckling-restrained brace, viewed from the direction IV-IV in Figure 3, and Figure 5 is a cross-sectional view of an example of the central part of the buckling-restrained brace, viewed from the direction VV in Figure 3. Furthermore, Figure 6 is a plan view of the buckling-restrained brace according to the embodiment, viewed from the direction VI in Figure 3.

[0034] As shown in Figure 1, the core material 10 is formed from a long, slender, plate-shaped flat steel, and has a narrow section 13 at the center of its longitudinal direction where the width of the wide surface 11a is relatively narrow, and two wide sections 12A and 12B at the ends in the longitudinal direction where the width of the wide surface 11a is relatively wide (the wide section 12B at the end is wider than the wide section 12A). In addition, reinforcing ribs 14 perpendicular to the wide surface 11a are welded to the wide surface 11a at the longitudinal end of the core material 10, giving it a cross-shaped cross section.

[0035] The core material 10 has a narrow section 13 on its longitudinal central side and a wide section 12 on its longitudinal end side. This allows the narrow section 13 on the central side to be made into a region that is easily plasticized (plasticization region A), and furthermore, the plasticization region A can be limited to the narrow section 13 on the central side.

[0036] In the core material 10, in the boundary region between the wide portion 12A and the narrow portion 13, the region on the narrow portion 13 side is a change region in which both the planar area and cross-sectional area of ​​the core material 10 change and become smaller, thus forming a plastic deformation region A that is easily plasticized.

[0037] Furthermore, in the illustrated example, reinforcing ribs 14 are attached to the wide section 12, and the rigidity of the wide section 12 is further increased, which makes it easier for a plastic deformation region A to form in the boundary region on the narrow section 13 side. The additional bending moment acting on the core material 10 is effectively absorbed in this plastic deformation region A.

[0038] Furthermore, bolt holes 12a and 14a are provided in the wide section 12 and the reinforcing rib 14, respectively, for bolt connection via splice plates to gusset plates provided on the structural surface and fin stiffeners (see Figure 9) attached to the gusset plates, as will be explained below.

[0039] When the buckling-restrained brace 100 is attached to the gusset plate such that the wide surface 11a of the core material 10 is arranged parallel to the structural plane of the building, the core material 10 has reinforcing ribs 14 perpendicular to the wide surface 11a that is parallel to the structural plane, thereby increasing the rigidity of the end of the core material 10 in the direction outward of the structural plane.

[0040] The core material 10 is preferably made of a steel material with a low yield point, such as SN material (rolled steel for building structures) or LYP material (ultra-low yield point steel), which improves the seismic energy absorption due to the yielding of the core material 10.

[0041] As shown in Figure 2, the restraint member 20 is formed by a pair of restraint plates 21 and a pair of spacers 25.

[0042] A pair of restraint plates 21 are arranged to face the two wide surfaces 11a of the core material 10. A recess 23 is provided at the end of the contact surface 22 of the restraint plate 21 with respect to the core material 10, so that when the contact surface 22 comes into contact with the wide surface 11a of the core material 10, a portion of the reinforcing rib 14 at the end of the core material 10 is accommodated in the recess 23.

[0043] The dimensions of the recess 23 are set so that a portion of the reinforcing rib 14 is accommodated with a gap between them, thereby preventing interference between the reinforcing rib 14 and the end of the restraining plate 21.

[0044] On the other hand, the spacer 25 is positioned so as to be sandwiched between the ends of the pair of restraint plates 21, and is fixed to the restraint plates 21 with an adhesive such as a urethane-based adhesive or an epoxy-based adhesive, or with axial fixing means such as screws, nails, or bolts.

[0045] The spacer 25 has a central portion 26 that corresponds to the narrow central portion 13 of the core material 10 and end portions 27 that correspond to the wide portions 12 at both ends of the core material 10, with the central portion 26 being relatively wider in a plan view.

[0046] The restraint plate 21 is a laminated timber formed by laminating and bonding multiple laminae together. As will be explained in detail below, the cross-sectional area, sectional stiffness, Young's modulus, etc., of the restraint member 20 are set so as to prevent overall buckling of the buckling-restrained brace. This Young's modulus is determined by the type of wood. Examples of wood types include cypress, Japanese red pine, Japanese larch, fir, and Yezo spruce.

[0047] On the other hand, the spacer 25 is formed from one of the following materials: wood, metal, or fiber reinforcement. In the illustrated example, the spacer 25 is made of wood, for example, wood of the same material as the restraint plate 21, and therefore the restraint material 20 is a wooden restraint material.

[0048] By forming the spacer 25 from wood as shown in the illustration, the entire restraint material 20 becomes made of wood, resulting in a restraint material with excellent aesthetic design.

[0049] On the other hand, if the spacer is made of metal materials such as iron or aluminum, or fiber-reinforced materials such as carbon fiber reinforced plastics (CFRP) or glass fiber reinforced plastics (GFRP), the rigidity and load-bearing capacity of the spacer can be improved compared to a wooden spacer, and failure of the spacer can be further suppressed.

[0050] The thickness of the spacer 25 may be the same as that of the core material 10, or it may be made thinner than the core material 10. In other words, when processing the spacer 25, it is not necessary to process it so that its thickness is exactly the same as that of the core material 10, and it may be made, for example, relatively slightly thinner.

[0051] In this way, by not strictly controlling the thickness of the spacer 25 during its manufacture, the manufacturing time for the spacer 25 can be shortened. Even if the thickness of the spacer 25 is slightly thinner than the thickness of the core material 10, for example, when the restraint plate 21 and the spacer 25 are fixed by the axial fixing means, the pair of wooden restraint plates 21 will displace from each other and join with the spacer 25.

[0052] As shown in Figure 3, a buckling-restrained brace 100 is formed by surrounding the core material 10 with a restraining material 20 (wooden restraining material in the illustrated example). Here, although not shown in the illustration, the core material 10 may have protrusions on both wide surfaces 11a, and the restraining plate 21 may have grooves at positions corresponding to the protrusions on the contact surface 22, so that the protrusions fit into the grooves on both sides, thereby preventing the core material 10 from shifting relative to the restraining material 20.

[0053] In the buckling-restrained brace 100, the restraining member 20 is formed by a pair of restraining plates 21 and a pair of spacers 25, eliminating the need for conventional side plates. This reduces the number of parts and thus lowers manufacturing costs.

[0054] As shown in Figures 4 and 6, at the end of the buckling-restrained brace 100, the wide surface 11a of the wide portion 12 of the core material 10 abuts against the contact surface 22 of the restraint plate 21, and the core material 10 is restrained by the restraint plate 21. A gap 28 is formed between the spacer 25 and the narrow surface 11b of the core material 10. Furthermore, a gap is also formed between the reinforcing rib 14 and the recess 23 of the restraint plate 21.

[0055] Thus, at the end of the buckling-restrained brace 100, there is a gap 28 between the spacer 25 and the core material 10, and there is also a gap between the recess 23 of the restraint plate 21 and the reinforcing rib 14. As a result, when the buckling-restrained brace 100 incorporated into the frame deforms in the strong axis direction or weak axis direction during an earthquake, the wide section 12 and the reinforcing rib 14 come into contact with the spacer 25 and the restraint plate 21, preventing damage to the ends of the spacer 25 and the restraint plate 21 due to the pressure on their wall surfaces.

[0056] On the other hand, as shown in Figures 5 and 6, in the central part of the buckling-restrained brace 100, a pair of restraint plates 21 contact the wide surface 11a of the core material 10, thereby preventing buckling of the core material 10 in the weak axis direction. In addition, a pair of spacers 25 contact the narrow surface 11b of the core material 10, thereby preventing displacement and buckling of the core material 10 in the strong axis direction.

[0057] Next, with reference to Figures 7 and 8, a modified example of the buckling-restrained brace will be described. Here, both Figures 7 and 8 are plan views of other examples of the buckling-restrained brace according to the embodiment.

[0058] The buckling-restrained brace 100A shown in Figure 7 has a configuration in which the spacer constituting the restraining member 20A is equipped with multiple segmented spacers 31 and 32.

[0059] Specifically, it has a first divided spacer 31 corresponding to the narrow portion 13 of the core material 10 and a second divided spacer 32 corresponding to the wide portion 12 of the core material 10, with a gap 33 provided between the first divided spacer 31 and the second divided spacer 32.

[0060] The first divided spacer 31 and the second divided spacer 32 are rectangular parallelepiped spacers with different cross-sectional dimensions and lengths, and their shape is simpler compared to the spacer 25 shown in Figure 2.

[0061] In other words, by arranging each divided spacer 31, 32 in a position corresponding to the narrow portion 13 and the wide portion 12 of the core material 10, the manufacturing effort of producing spacers while changing their shape to correspond to the narrow portion 13 and the wide portion 12 of the core material 10 can be eliminated.

[0062] Furthermore, by eliminating the placement of spacers in areas where problems such as local buckling of the core material 10 are not expected (in the illustrated example, the gap 33 in the transition region between the wide portion 12 and the narrow portion 13 of the core material 10), it becomes possible to reduce the material cost of the spacers.

[0063] On the other hand, the buckling-restrained brace 100B shown in Figure 8 is a configuration in which the spacers constituting the restraining material 20B are provided with a separate set of divided spacers 35 and 36.

[0064] Specifically, the core material 10 has a third divided spacer 35 that extends from the wide section 12 to the middle of the narrow section 13, and a fourth divided spacer 36 that corresponds to the central region of the narrow section 13, with a gap 37 provided between the third divided spacer 35 and the fourth divided spacer 36.

[0065] By having a third-part spacer 35 and a fourth-part spacer 36, for example, compared to the spacer 25 shown in Figure 2, it is possible to install a continuous spacer from the wide section 12 to partway through the narrow section 13 of the core material 10 while keeping the length of the spacer as short as possible.

[0066] Furthermore, similar to the buckling-restrained brace 100A, by eliminating the placement of spacers in areas where local buckling of the core material 10 is not expected to occur (in the illustrated example, the gaps 37 are located midway between the left and right sides of the narrow section 13 of the core material 10), it becomes possible to reduce the material cost of the spacers.

[0067] In this illustrated example, the ends of the third divided spacer 35 and the fourth divided spacer 36 are fixed to the restraint plate 21 by axial fixing means 40 such as bolts.

[0068] In this way, since the ends of the divided spacers 35 and 36 are fixed to the restraint plate 21 by the axial fixing means 40, if there is a risk of localized damage to the wooden restraint plate 21 at the ends of the divided spacers 35 and 36, the axial fixing means 40 that fixes the restraint plate 21 to the spacers 35 and 36 can suppress localized damage to the restraint plate 21.

[0069] [Framework incorporating buckling-restrained braces] Next, with reference to Figures 9 and 10, an example of a building frame incorporating the buckling-restrained brace of the embodiment will be described. Here, Figure 9 shows the buckling-restrained brace according to the embodiment incorporated into the frame of a wooden building or the like. Figure 10 is a diagram illustrating the deformation of the frame during a major earthquake and the additional bending moment at the buckling-restrained brace joint caused by the deformation of the frame. Note that the buckling-restrained brace in the illustrated example may be incorporated not only into the frame of a wooden building, but also into the frame of a steel (S) building, a reinforced concrete (RC) building, or a steel-reinforced concrete (SRC) building.

[0070] The frame S shown in Figure 9 is formed by wooden columns C and beams B that make up a wooden building. Gusset plates GP made of flat steel are attached to the two diagonal corners. Fin stiffeners FS are welded to the surface of the gusset plates GP so as to be perpendicular to the surface. The fin stiffeners FS are joined to the gusset plates GP such that their center L3 intersects the intersection point O of the column center L1 of column C and the beam center L2 of beam B. The buckling-restrained braces 100 are also arranged linearly, passing through the intersection points O of both diagonally opposite positions.

[0071] The gusset plate GP and the wide portion 12 of the core material 10 are joined via a splice plate SP by high-tension bolts, and the fin stiffener FS and the reinforcing rib 14 are joined via a splice plate SP by high-tension bolts.

[0072] As shown in Figure 10, during a major earthquake, the structural plane deforms, and in the buckling-restrained brace joint, an additional bending moment shown in equation (1) below may act, assuming the joint is rigid.

[0073]

number

[0074] With the buckling-restrained brace 100, a gap 28 is provided between the narrow surface 11b of the wide portion 12 of the core material 10 and the spacer 25 (27), and a gap is provided between the reinforcing rib 14 of the core material 10 and the recess 23 of the restraint plate 21. As a result, when the structural surface to which the buckling-restrained brace 100 is attached undergoes a large deformation, these gaps absorb the deformation of the core material 10, preventing additional bending moments from acting on the wooden restraint material 20. This prevents the core material 10 from contacting and further pressing against the wall surface of the wooden restraint material 20, thereby preventing damage to the wooden restraint material 20.

[0075] [Consideration of overall buckling] Next, we will explain a design method for preventing overall buckling of a buckling-restrained brace.

[0076] In designing buckling-restrained braces, the following equation (2) should be satisfied so that overall buckling of the buckling-restrained brace does not occur.

[0077]

number

[0078] Here, the bending moment acting at the center of the restraint plate can be expressed by the following equation (3).

[0079]

number

[0080] The condition for preventing overall buckling of the wooden restraint material is that the following equation (4) is satisfied.

[0081]

number

[0082] Equation (4) is shown in Figure 9 as the overall buckling curve of the buckling-restrained brace. In Figure 9, the area above the overall buckling curve is the safety zone, and the area below is the danger zone. The design axial force of the wooden restraint, Euler load, length of the general part of the core material, and yield bending strength of the wooden restraint are set so that the brace falls within the safety zone. Note that the overall buckling curve of the buckling-restrained brace shown in Figure 9 is valid for both overall buckling in the weak axis direction and overall buckling in the strong axis direction of the core material.

[0083] In addition to examining the relationship between the yield bending strength of the wooden restraint material and the bending moment acting on it, it is also advisable to examine that the short-term allowable bending strength of the wooden restraint material is greater than the bending moment acting on it when the core material yields (formulas omitted).

[0084] <Investigation of failure due to indentation of wooden restraint materials> Next, we will explain how to examine the failure of wooden restraints due to indentation. In order to prevent the wooden restraint from failing due to the core material indenting into it, use the following equation (5) Verify that you are satisfied.

[0085]

number

[0086] Here, in addition to checking the relationship between the indentation resistance of the restraint plate and the acting stiffening force, it is also advisable to check that the short-term allowable indentation resistance of the restraint plate is greater than the stiffening force acting at the time of core material yielding (formulas omitted).

[0087] 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]

[0088] 10: Core material 11a: Wide surface 11b:Narrow side 12, 12A, 12B: Wide section 12a: Bolt hole 13: Narrow section 14: Reinforcement Ribs 14a: Bolt hole 20, 20A, 20B: Retaining material (wooden retaining material) 21: Restraint board (laminated wood) 22: Contact surface 23: Recess 25: Spacer 26: Central part 27: End 28: Gap 31: First split spacer (split spacer) 32: Second split spacer (split spacer) 33: Gap 35: Third-part spacer (split spacer) 36: Fourth split spacer (split spacer) 37: Gap 40: Axial fixing means 100, 100A, 100B: Buckling-restrained brace A: Plasticization region S: Frame (composition) C: Pillar B: Beam GP: Gusset Plate FS: Finstiffna SP: Splice Plate

Claims

1. A steel, plate-shaped core material, The restraining member comprises a pair of wooden restraining plates arranged to face the two wide surfaces of the core material, and a pair of spacers arranged to face the two narrow surfaces of the core material and connected to the pair of restraining plates, The core material has a narrow section at its longitudinal center where the width of the wide surface is relatively narrow, and a wide section at its longitudinal end where the width of the wide surface is relatively wide. The pair of spacers abut against the narrow surface of the narrow portion and have a gap between them and the narrow surface of the wide portion. A buckling-restrained brace characterized in that the spacer comprises a plurality of divided spacers, the divided spacers being a first divided spacer corresponding to the narrow portion and a second divided spacer corresponding to the wide portion.

2. A steel, plate-shaped core material, The restraining member comprises a pair of wooden restraining plates arranged to face the two wide surfaces of the core material, and a pair of spacers arranged to face the two narrow surfaces of the core material and connected to the pair of restraining plates, The core material has a narrow section at its longitudinal center where the width of the wide surface is relatively narrow, and a wide section at its longitudinal end where the width of the wide surface is relatively wide. The pair of spacers abut against the narrow surface of the narrow portion and have a gap between them and the narrow surface of the wide portion. A buckling-restrained brace characterized in that the spacer comprises a plurality of segmented spacers, the segmented spacers being a third segmented spacer extending from the wide portion to the middle of the narrow portion, and a fourth segmented spacer corresponding to the central region of the narrow portion.

3. The buckling-restrained brace according to claim 1 or 2, characterized in that there is a gap between the divided spacers.

4. The buckling-restrained brace according to any one of claims 1 to 3, characterized in that the end of the divided spacer is fixed to the restraint plate by an axial fixing means.

5. A steel, plate-shaped core material, The restraining member comprises a pair of wooden restraining plates arranged to face the two wide surfaces of the core material, and a pair of spacers arranged to face the two narrow surfaces of the core material and connected to the pair of restraining plates, A buckling-restrained brace characterized in that the thickness of the spacer is thinner than the thickness of the core material.

6. The buckling restraint brace according to any one of claims 1 to 5, characterized in that the restraint plate and the spacer are connected by an adhesive or an axial fixing means.

7. The buckling-restrained brace according to any one of claims 1 to 6, characterized in that the spacer is formed of one of wood, metal, or fiber reinforcement.

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