JP2020041319A - Joint structure of main structure and brace - Google Patents

Abstract

A joint structure between a main structure and a brace that can increase the out-of-plane rigidity of a gusset plate even when a fin stiffener cannot be extended to the joint corner of a column and a beam on the gusset plate. A joint structure (100) between the main structure and the brace, which is composed of a main structure (30) formed by a column (10) and a beam (20) and a brace (60), and a gusset plate (40) is attached to the main structure (30). A fin stiffener 50 is attached to each side of the gusset plate 40 perpendicularly to the gusset plane. has a first fin stiffener 51 extending in the longitudinal direction of the brace 60, and a second fin stiffener 52 bent from an end portion 51a of the first fin stiffener 51 and extending toward the beam 20 side. [Selection drawing] Fig. 1

Description

  The present invention relates to a joint structure between a main structure formed by columns and beams and a brace.

  In a structure of a building, when pillars and beams forming a main structure are pin-coupled structures, a brace is generally arranged in a plane formed by the columns and beams. The brace is bolted or the like to the gusset plate attached to the joint between the column and the beam via the splice plate, thereby forming a joint structure between the main structure and the brace. For example, according to the steel structural joint design guideline (Architectural Institute of Japan), it is preferable to attach the brace to the gusset plate at a gradient where the axis of the brace coincides with the intersection of the axis of the column and the axis of the beam. It has been. By arranging the brace on the construction surface, the in-plane rigidity of the construction surface in the event of an earthquake or the like is increased, while the out-of-plane rigidity of the gusset plate and the brace attached to this gusset plate is low. In this case, there is a concern that the joint structure of the main structure and the brace may withstand vibrations in the out-of-plane direction and external force. That is, there is a concern that the joint structure between the main structure and the brace may be damaged before the brace exerts its performance against vibration during an earthquake.

  Therefore, in order to increase the out-of-plane rigidity of the gusset plate, a structure in which a fin stiffener is attached perpendicularly to a gusset plane of the gusset plate is applied. According to the guideline for steel structure buckling design (Architectural Institute of Japan), as a measure to increase the out-of-plane rigidity of the gusset plate to which the brace is attached, not only simply attaching the fin stiffener to the gusset plate, but also It has been proposed to attach a horizontal side stiffener to the part and to attach a vertical side stiffener to the vertical end of the gusset plate.

  On the other hand, according to the Steel Structure Vibration Suppression Design Guideline (Architectural Institute of Japan), the brace is attached to the gusset plate at a gradient where the axis of the brace coincides with the intersection of the axis of the column and the axis of the beam. It is said that the fin stiffener is preferably arranged on the slope and attached to the gusset plate. When the fin stiffener is attached to the gusset plate in this way, a brace having a cross-section at the end joined to the gusset plate may be applied. This brace is a buckling restrained brace composed of a core material and a pair of restraining members disposed along both surfaces of the core material. Reinforcing ribs are provided. The core and the gusset plate are bolted together via a splice plate, and the two reinforcing ribs and the fin stiffener are bolted together via a separate splice plate.

  By the way, when attaching the fin stiffener to the gusset plate attached to the joint between the column and the beam, various members protrude or are arranged at the joint between the column and the beam. As such, it is often not possible to extend the fin stiffener along the axis of the brace extending toward the intersection of the axis of the column and the beam to the joint corner of the column and beam. In particular, SRC columns (Steel) in which the column is a coated type (type in which the surroundings of a steel frame is covered with concrete) or a filled type (a type in which concrete is filled in the inside of a steel frame and the surroundings of the steel frame are covered with concrete) In the case of Reinforced Concrete (steel-framed reinforced concrete), column main reinforcement is arranged around a steel column made of square steel pipe or H-section steel, and shear reinforcement is arranged around the column main reinforcement, and concrete is poured. Is disposed on the outer periphery of the pillar. For this reason, the fin stiffener cannot be extended at least to the joint corner portion between the column and the beam from the position of the formwork, and the end of the fin stiffener may stop at an intermediate position of the gusset plate. Therefore, in such a case, the fin stiffeners not having a sufficient length do not sufficiently stiffen the out-of-plane rigidity of the gusset plate. In addition, an H-shaped cross-section bracket for column connection is extended laterally from a corner of a column and a beam, and a beam formed of H-shaped steel is bolted to the H-shaped cross-section bracket via a splice plate. In such a case, the vertical side stiffeners may separate the splice plate connecting the upper flanges of the bracket and the beam, and in such a case, the gusset plate can be stiffened by the vertical side stiffeners. Disappears.

  As described above, in order to increase the out-of-plane rigidity of the gusset plate by the fin stiffener, the fin stiffener must be sufficiently extended to the joint corner between the column and the beam due to the restriction due to the existence of various members at the joint between the column and the beam. Even in cases where it is not possible, it is desired to develop a technique for effectively increasing the out-of-plane rigidity of the gusset plate without applying a side stiffener or the like, thereby increasing the out-of-plane rigidity in the joint structure between the main structure and the brace. .

  Here, a joint structure of a gusset plate and a vibration damping brace provided at a corner where a column and a beam of a steel frame including a brace intersect is proposed. In this joining structure, a cylindrical rod having a diameter smaller than the inner diameter of the sleeve pipe is provided on both ends of a cylindrical sleeve pipe having an open end and a closed end and fixed to a gusset plate so that the open end faces diagonally. The damping brace rod provided in the above is inserted and fitted, and a gap in the sleeve tube formed by the sleeve tube and the rod fitted therein is filled with a joining material for damping brace joining (for example, And Patent Document 1).

JP 2018-109276 A

  Patent Document 1 describes a fin stiffener. However, there is no description on how to increase the out-of-plane rigidity of the gusset plate when the fin stiffener cannot be extended to the joint corner between the column and the beam on the gusset plate.

  The present invention has been made in view of the above-described problem, and can improve the out-of-plane rigidity of a gusset plate even when a fin stiffener cannot be extended to a joint corner of a column and a beam on a gusset plate. It is intended to provide a joint structure between the structure and the brace.

In order to achieve the above object, one embodiment of the joining structure of the main structure and the brace according to the present invention is:
A main structure formed by columns and beams, and a brace, which is a joint structure of the main structure and the brace,
A gusset plate is attached to the main structure, and fin stiffeners are attached to both sides of the gusset plate perpendicularly to the gusset plane, respectively.
The brace and the gusset plate are bolted via a splice plate,
The fin stiffener has a first fin stiffener extending in a longitudinal direction of the brace, and a second fin stiffener bent from an end of the first fin stiffener and extended to the beam side. And

  According to this aspect, the first fin stiffener extending in the longitudinal direction of the brace is formed by bending the fin stiffener extending in the longitudinal direction of the brace and extending toward the beam side forming the main structure. Even if it does not extend to the joint corner of the column and the beam, it has a second fin stiffener that bends from the first fin stiffener and extends to the beam side, without increasing the thickness of the gusset plate. Out-of-plane rigidity can be effectively increased. Further, even when there are various projections (studs with heads, etc.) provided at the joint corners of the column and the beam, and there are interferences such as a formwork for SRC column construction, the first fin stiffener is not supported. By moving to the second fin stiffener that is bent at the beam side and extends to the beam side, these interferences can be effectively avoided. Here, regarding the “second fin stiffener bent from the end of the first fin stiffener and extending to the beam side”, the form in which the second fin stiffener extends to the beam and, for example, the side from the column core constituting the column And extending to a bracket joined to the beam.

  As described above, the guideline for steel structure buckling design (Architectural Institute of Japan) proposes a structure in which a side stiffener is provided at a position independent of a fin stiffener as a measure for increasing the out-of-plane rigidity of the gusset plate. On the other hand, in this aspect, since the second fin stiffener bent so as to be continuous with the first fin stiffener extending in the longitudinal direction (axial direction) of the brace is provided, the first fin stiffener and the second fin stiffener are provided. In the case where the fin stiffener is not divided and therefore the fin stiffener is divided, a problem that the dividing portion (the portion where the fin stiffener does not exist) becomes a low rigidity portion and becomes a stress concentration portion does not occur. In addition, when the side stiffener is provided, the side stiffener may divide the splice plate connecting the bracket and the upper flange of the beam, but in this embodiment, the second fin stiffener extending toward the beam is located above the beam. By setting the axis of the second fin stiffener so that the splice plate connecting the flanges is not divided, such a problem does not occur. The brace is preferably arranged such that its longitudinal direction is arranged at the intersection of the axis of the column and the axis of the beam, but the width of the construction surface (the distance between the left and right columns where the brace is arranged) Depending on the height and height, there is also a form in which the longitudinal direction of the brace is arranged at a position shifted from the intersection of the axis of the column and the axis of the beam.

In another aspect of the joint structure between the main structure and the brace according to the present invention, the beam is formed of an H-shaped steel,
The second fin stiffener is bent from an end of the first fin stiffener in a direction orthogonal to an upper flange of the beam or a bracket connecting the beam and the column, and intersects at an intersection with the upper flange, A web stiffener is provided on the side of the beam or the web of the bracket, connecting the upper flange and the lower flange from the intersection.

  According to this aspect, in addition to the first fin stiffener and the second fin stiffener that enhance the out-of-plane stiffness of the gusset plate, the H-shaped cross section connecting the beam or the column made of the H-shaped steel crossed by the second fin stiffener or the beam A web stiffener connecting the upper and lower flanges of the bracket is provided on the side of the beam or the web of the bracket. Therefore, a joint structure of the main structure and the brace having higher out-of-plane rigidity is formed.

Further, in another aspect of the joining structure of the main structure and the brace according to the present invention, the first fin stiffener and the gusset plate are welded and joined,
The length of the first fin stiffener satisfies a welding length at which a shear strength at a welding portion between the first fin stiffener and the gusset plate is equal to or greater than an axial force acting on the first fin stiffener from the brace. It is characterized by length.

  According to this aspect, the axial force (brace axial force) transmitted from the brace to the splice plate via the bolt is transmitted from the splice plate to the first fin stiffener via the bolt, and the welded portion is transmitted from the first fin stiffener. Through the gusset plate and flow to the main structure. In addition, since the first fin stiffener and the second fin stiffener, which is bent and continuous to the fin stiffener, are also joined to the gusset plate via the welding portion, the welding for transmitting the axial force from the first fin stiffener to the gusset plate is performed. The portion includes not only a welded portion for joining the gusset plate and the first fin stiffener, but also a welded portion for joining the gusset plate and the second fin stiffener. However, the first fin stiffener has a high safety factor by setting the length of the first fin stiffener so that the shear strength at the welded portion between the first fin stiffener and the gusset plate satisfies the welding length at which the axial strength is equal to or more than the axial force. A welded structure between the fin stiffener and the gusset plate can be formed. The axial force of the brace when setting the length of the first fin stiffener is the distribution axial force distributed to the first fin stiffener because the brace axial force is distributed to both the gusset plate and the first fin stiffener. , The length of the first fin stiffener is set.

In another aspect of the joint structure between the main structure and the brace according to the present invention, the brace has a core and a pair of restraining members disposed along both surfaces of the core,
The pair of restraining members are each formed of a channel steel whose core material side is open, and a cement-based material filled in the channel steel,
On both surfaces of the core, reinforcing ribs projecting perpendicular to the surface and extending in the longitudinal direction of the core from both ends of the restraining member are provided, and the end of the brace is A buckling-restrained brace having a cross-sectional shape formed by a core material and two of the reinforcing ribs,
The core and the gusset plate are bolted together via a first splice plate, and the two reinforcing ribs and the first fin stiffener are bolted together via a second splice plate. .

  According to this aspect, the buckling restrained brace formed by the core material and the pair of restraining materials has two reinforcing ribs at the ends of the core material, so that the cross-sectional shape is a cross shape, and the core material and the gusset plate And the two reinforcing ribs and the first fin stiffener are bolted to each other via their own splice plates, so that the main structure and the brace have a higher out-of-plane rigidity. Here, the “cement-based material” filled in the channel steel includes mortar and concrete.

  Further, another aspect of the joining structure of the main structure and the brace according to the present invention includes a number of bolts for joining the core member and the first splice plate, and a number of bolts for joining the reinforcing rib and the second splice plate. Is set according to the ratio of the thickness of the core material to the thickness of the reinforcing rib.

  According to this aspect, in a mode in which the end of the brace has a cross-shaped cross section with the reinforcing rib, while the axial force of the brace is distributed according to the thickness of the core material and the thickness of the reinforcing rib, It is possible to set the number of bolts appropriately reflecting the transmission to the first fin stiffener and the gusset plate via the corresponding splice plate. For example, when the ratio of the thickness of the core member to the reinforcing rib is 1: 1 or 3: 2, the number of bolts for connecting the core member to the first splice plate and the number of bolts for connecting the reinforcing rib to the second splice plate are different. The number ratio is also preferably 1: 1 or 3: 2.

  Another aspect of the joint structure of the main structure and the brace according to the present invention is that, when the pillar is an SRC pillar, the end of the first fin stiffener that bends and shifts to the second fin stiffener is the SRC pillar. It is characterized by being in a position that does not interfere with the pillar.

  According to this aspect, since the second fin stiffener is bent from the end of the first fin stiffener and extends to the beam side, when the pillar is an SRC pillar, the surface of the SRC pillar or during construction By bending the second fin stiffener from the first fin stiffener to the beam side at the position avoiding the formwork, the interference between the fin stiffener and the SRC column can be eliminated.

  As can be understood from the above description, according to the joint structure of the main structure and the brace of the present invention, even if the fin stiffener cannot be extended to the joint corner of the column and the beam on the gusset plate, The rigidity can be increased.

It is a front view of an example of the joining structure of a main structure and a brace concerning an embodiment. It is a perspective view of an example of the buckling restrained brace which comprises a joining structure. It is a perspective view which shows only the gusset plate to which the fin stiffener was welded. It is a perspective view which shows the joining part of a buckling restraint brace, a fin stiffener, and a gusset plate.

  Hereinafter, a joining structure of a main structure and a brace according to an embodiment of the present invention will be described with reference to the accompanying drawings. In the specification and the drawings, substantially the same components are denoted by the same reference numerals, and redundant description may be omitted.

[Joint structure of main structure and brace according to embodiment]
The joint structure between the main structure and the brace according to the embodiment will be described with reference to FIGS. Here, FIG. 1 is a front view of an example of a joint structure of the main structure and the brace according to the embodiment, and is a diagram in which the concrete of the pillar is omitted in the region of the connection structure so that the inside is visible. FIG. 2 is a perspective view of an example of a buckling restrained brace forming a joint structure, and FIG. 3 is a perspective view showing only a gusset plate to which a fin stiffener is welded. FIG. 4 is a perspective view showing a joint between the buckling restrained brace, the fin stiffener, and the gusset plate. Note that any one of fillet welding and butt welding is applied to “welding” described below, and a suitable welding mode is selected according to a welding location.

  As shown in FIG. 1, the joint structure 100 of the main structure and the brace is a joint structure including the main structure 30 formed by the columns 10 and the beams 20 and the brace 60. More specifically, the present invention is characterized in a connection structure between the gusset plate 40 and the brace 60 which are joined to the main structure 30 by welding.

  The column 10 in the illustrated example is an SRC column, and is a coated SRC column in which a steel column 13 formed of a square steel pipe or the like is covered with a surrounding concrete body 14, but a concrete body is also provided in the square steel pipe. The formed filling-coated SRC pillar may be used. More specifically, the upper and lower through-diaphragms 12 are joined by welding above and below the column core 11 (panel zone), and the upper and lower floor steel columns 13 are joined to the upper and lower through-diaphragms 12 by welding. A main reinforcing bar (not shown) extending in the longitudinal direction of the column is arranged around these, and a shear reinforcing bar (not shown) surrounding the plurality of main reinforcing bars has a predetermined pitch in the longitudinal direction of the column. Placed and arranged. Further, the pillar 10 is formed by forming a concrete body 14 burying the main reinforcing bars and the shear reinforcing bars around the steel column 13. In FIG. 1, the axis of the column 10 is indicated by L1. Note that the column 10 is not limited to the SRC column in the illustrated example, and may be a steel column made only of a shaped steel material such as a square steel pipe or an H-shaped steel.

  On the other hand, an H-shaped bracket 15 is welded to the side surfaces of the upper and lower through diaphragms 12 and the column core 11 by welding. More specifically, an upper flange 15b and a lower flange 15c constituting the bracket 15 are respectively joined to the upper and lower through-diaphragms 12, and a web 15a constituting the bracket 15 is joined to a side surface of the column core 11. Although the illustrated example shows a form in which the bracket 15 is joined to the left side of the column core 11, the same applies to any one or all of the right side of the column core 11, the near side of the sheet, and the back side of the sheet. The bracket 15 may be welded. Actually, it is transported on site with the bracket 15 joined to the column core 11.

  A beam 20 formed of an H-shaped steel having the same dimensions is joined to the bracket 15. More specifically, the upper flange 15b of the bracket 15 and the upper flange 20b of the beam 20 are joined by a bolt 90 via a splice plate 82. Similarly, the lower flange 15c of the bracket 15 and the lower flange 20c of the beam 20 Are joined by a bolt 90 via a splice plate 82. Further, the web 15 a of the bracket 15 and the web 20 a of the beam 20 are joined by bolts 90 via a splice plate 81. These bolts 90 are, for example, high tension bolts. In FIG. 1, the axis of the beam 20 is indicated by L2, and the axis L2 and the axis L1 of the column 10 intersect at an axis intersection O.

  A gusset plate 40 formed of a steel plate is joined to the steel column 13 and the upper flange 15b of the bracket 15 by welding. That is, the gusset plate 40 is joined to the main structure 30.

  The gusset plate 40 has a brace 60 extending diagonally to a face formed by left and right pillars 10 (only the right pillar 10 is shown in the drawing) and upper and lower beams 20 (only the lower beam 20 is shown in the drawing). Are joined at one end.

  As shown in FIG. 2, the brace 60 is a buckling restrained brace having a core material 61 and a pair of restraining members 64 disposed along both surfaces of the core material 61. The pair of restraining members 64 are each formed by a channel steel 62 having an opening on the core material 61 side, and a cement-based member 63 formed by hardening a cement-based material filled in the channel steel 62. In addition, this cement-based material includes mortar and concrete.

  The core material 61 is formed of a strip-shaped elongated flat steel plate, and the flat steel plate is made of a steel material having a low yield point such as an SN material (rolled steel material for building structure) or an LY material (extremely low yield point steel material). An unbond material (not shown) may be attached to a surface of the core material 61 facing the restraining material 64, and the unbond material is formed of a plate-like or sheet-like butyl rubber, another viscoelastic body, or the like. Is done.

  Further, both ends of the core member 61 protrude from both ends of the restraining member 64, and serve as joints to be joined to the gusset plate 40 and the like. At the center position of the upper and lower wide surfaces of the core material 61 forming this joint, while projecting perpendicularly to the wide surface, while projecting outward from the slits 62 a formed at both ends of the restraining member 64. Further, reinforcing ribs 65 extending in the longitudinal direction of the core material 61 are joined by welding. The end of the buckling restrained brace 60 has a cross-section formed by the core member 61 and the two reinforcing ribs 65. The thickness of both the core material 61 and the reinforcing rib 65 may be the same or different, but when the thickness is different, the thickness of the core material 61 is set to be relatively large. Based on the design concept that the brace axial force is distributed according to the thickness of both the core material 61 and the reinforcing rib 65, a number of bolt holes 61a and 65a corresponding to both thicknesses are opened. I have. In the illustrated example, based on the thickness t3 of the core member 61 and the thickness of the reinforcing rib 65 being set to, for example, 3: 2, the ratio of the number of the bolt holes 61a and 65a is also set to 3: 2. I have.

  Returning to FIG. 1, the buckling restrained brace 60 is disposed in the plane at an angle where the axis L <b> 3 intersects the axis intersection point O, and is joined to the gusset plate 40. A fin stiffener 50 is welded to both gusset planes of the gusset plate 40 by welding, and the fin stiffener 50 enhances the out-of-plane rigidity of the gusset plate 40 outside the construction surface. More specifically, as shown in FIGS. 1 and 3, the fin stiffener 50 is bent from a first fin stiffener 51 extending in the longitudinal direction of the buckling restrained brace 60 and an end 51 a of the first fin stiffener 51. And a second fin stiffener 52 extending toward the beam 20 constituting the main structure 30.

  As is clear from FIG. 1, if the first fin stiffener 51 is extended to the joint corner between the column and the beam without bending, the surface 14 a of the concrete body 14 and the first fin stiffener 51 interfere with each other. , Cannot be extended to the joint corner of the column and the beam. Also, at the construction stage of the concrete body 14, since the formwork (not shown) is attached to the inside of the construction surface from the surface 14a, the first fin stiffener 51 also interferes with this formwork.

  If the end of the first fin stiffener 51 does not extend to the joint corner between the column and the beam and stops at an intermediate position of the gusset plate 40, the first fin stiffener 51 does not have a sufficient length. Also, since the entire gusset plate 40 is not covered with the first fin stiffener 51, the stiffening of the out-of-plane rigidity of the gusset plate 40 becomes insufficient.

  Therefore, as shown in FIGS. 1 and 3, the end 51 a of the first fin stiffener 51 is connected to an interference member (concrete body 14 shown, formwork not shown, or the like) existing at the joint corner between the column and the beam. The first fin stiffener 51 is bent at a position that does not interfere with the first fin stiffener 51, and a second fin stiffener 52 is provided to extend to the beam 20 side continuously to the end 51 a of the first fin stiffener 51. As shown in FIG. 1, the second fin stiffener 52 abuts on the upper flange 15b of the bracket 15 joined to the beam 20 in a manner orthogonal to the upper flange 15b, and is joined to the upper surface of the upper flange 15b by welding. The intersection between the second fin stiffener 52 and the upper flange 15b is defined as an intersection P.

  The core material 61 and the gusset plate 40 constituting the buckling restrained brace 60 are joined by bolts 90 via a first splice plate 71 made of steel. The two reinforcing ribs 65 and the first fin stiffener 51 constituting the buckling restrained brace 60 are joined by bolts 90 via a second splice plate 72 made of steel. The first splice plate 71 and the second splice plate 72 are collectively referred to as a splice plate 70.

  As shown in FIG. 1, the intersection point P between the second fin stiffener 52 and the upper flange 15 b does not divide (do not intersect) the splice plate 82 connecting the upper flange 15 b of the bracket 15 and the upper flange 20 b of the beam 20. The second fin stiffener 52 is disposed such that That is, the fin stiffener 50 is bent at a position where the first fin stiffener 51 does not interfere with the concrete body 14 and shifts to the second fin stiffener 52, and the upper fin stiffener 52 is positioned at a position where the second fin stiffener 52 does not divide the splice plate 82. 15b.

  Since the fin stiffener 50 is joined to the gusset plate 40 as described above, the fin stiffener 50 has the second fin stiffener 52 that is bent from the first fin stiffener 51 and extends to the beam 20 side. , The out-of-plane rigidity of the gusset plate 40 can be effectively increased. Also, since the second fin stiffener 52 is continuous by bending from the end 51a of the first fin stiffener 51, the first fin stiffener and the second fin stiffener are not separated, and thus the fin stiffener is separated. In this case, there is no problem that the divided portion becomes a low-rigidity portion and becomes a stress concentration portion (a weak portion of the structure of the gusset plate 40).

  As shown in FIG. 1, the second fin stiffener 52 is bent from the end 51 a of the first fin stiffener 51 on the beam 20 side to the upper flange of the bracket 15 having an H-shaped cross section in a direction orthogonal to 15 b, It intersects with the upper flange 15b at the intersection P and is joined to the upper flange 15b by welding. At a position corresponding to the intersection P, a web stiffener 53 connecting the upper flange 15b and the lower flange 15c is welded to the side of the web 15a of the bracket 15 having the H-shaped cross section.

  As described above, the position (intersection P) of the upper flange 15b to which the component force of the brace axial force flowing through the second fin stiffener 52 is directly transmitted via the first fin stiffener 51 is changed from the web stiffener 53 from below. By stiffening at, local breakage of the bracket 15 due to the component force of the brace axial force can be suppressed, and a highly rigid joint structure 100 can be formed.

  Next, a method of setting the length of the first fin stiffener 51 will be described. As shown in FIG. 3, when the length of the first fin stiffener 51 is t1 and the length of the second fin stiffener 52 is t2, both of them are welded to the gusset plate 40 via the welds Y1 and Y2. Are joined. In particular, the length t1 of the first fin stiffener 51 is set based on the welding length required for design at the corresponding welded portion Y1, in addition to the length for avoiding the interference member as described above. Is done.

  Specifically, the axial force N (brace axial force) acting from the buckling restrained brace 60 is a component force N1, N2 corresponding to the thickness of the core material 61 constituting the buckling restrained brace 60 and the thickness of the reinforcing rib 65. And transmitted to the gusset plate 40 and the first fin stiffener 51, respectively. Therefore, the first fin stiffener 51 is designed such that the shear strength at the two welds Y1 joining the first fin stiffener 51 and the gusset plate 40 is equal to or more than the component N2 of the axial force transmitted to the first fin stiffener 51. The length t1 may be set.

  In addition, not only the first fin stiffener 51 but also the second fin stiffener 52 connected thereto are joined to the gusset plate 40 via the welded portion Y2. Therefore, the welded portion transmitting the component force N2 of the axial force N from the first fin stiffener 51 to the gusset plate 40 is not only the welded portion Y1 joining the gusset plate 40 and the first fin stiffener 51, but also the gusset plate 40 and the gusset plate 40. There is also a weld Y2 that joins the two fin stiffeners 52. However, the length t1 of the first fin stiffener 51 is set such that the shear strength at the weld Y1 between the first fin stiffener 51 and the gusset plate 40 satisfies the welding length at which the axial force N has a component force N2 or more. By doing so, a welded structure between the first fin stiffener 51 and the gusset plate 40 having a high safety factor can be formed.

  Next, the number of bolts 90 for joining the core material 61 and the gusset plate 40 via the first splice plate 71 and the number of bolts 90 for joining the reinforcing rib 65 and the first fin stiffener 51 via the second splice plate 72 are shown. A method for setting the number will be described. As shown in FIG. 4, the thickness of the core member 61 and the gusset plate 40 constituting the buckling restrained brace 60 are both t3, and the thickness of the reinforcing rib 65 and the first fin stiffener 51 constituting the buckling restrained brace 60 are Both are t4, and in the illustrated example, t3: t4 = 3: 2, for example. In this case, the axial force N acting from the buckling restrained brace 60 becomes component forces N1 and N2 corresponding to the ratio of the thickness of the core member 61 to the reinforcing rib 65 at the end thereof, and becomes the gusset plate 40 and the first fin stiffener. It is rational in design that it is transmitted to 51. That is, in the illustrated example, N1: N2 = 3: 2. Therefore, the number of bolts 90 for joining the core material 61 and the gusset plate 40 via the first splice plate 71 and the bolt 90 for joining the two reinforcing ribs 65 and the first fin stiffener 51 via the second splice plate 72 are provided. The number of bolts is set such that the ratio of the number of bolts is 3: 2. For example, when t3: t4 = 1: 1, the ratio of the number of both bolts 90 is preferably 1: 1.

  It should be noted that other embodiments in which other components are combined with the configuration and the like described in the above embodiment may be adopted, and the present invention is not limited to the configuration shown here. This can be changed without departing from the spirit of the present invention, and can be appropriately determined according to the application form.

  10: Column, 11: Column core, 12: Through diaphragm, 13: Steel column, 14: Concrete body, 15: Bracket, 20: Beam, 30: Main structure, 40: Gusset plate, 50: Fin stiffener, 51: No. One fin stiffener, 52: Second fin stiffener, 53: Web stiffener, 60: Buckling restrained brace (brace), 61: Core material, 62: Channel steel, 63: Cement-based member, 64: Restraining material, 65: Reinforcing rib, 70: splice plate, 71: first splice plate, 72: second splice plate, 81, 82: splice plate, 90: bolt, 100: joint structure (joint structure) of main structure and brace, L1: pillar , L2: beam center, L3: brace axis, O: axis intersection, P: intersection (intersection of second fin stiffener and upper flange)

Claims (6)

A main structure formed by columns and beams, and a brace, which is a joint structure of the main structure and the brace,
A gusset plate is attached to the main structure, and fin stiffeners are attached to both sides of the gusset plate perpendicularly to the gusset plane, respectively.
The brace and the gusset plate are bolted via a splice plate,
The fin stiffener has a first fin stiffener extending in a longitudinal direction of the brace, and a second fin stiffener bent from an end of the first fin stiffener and extended to the beam side. The joint structure of the main structure and the brace. The beam is formed of H-section steel,
The second fin stiffener is bent from an end of the first fin stiffener in a direction orthogonal to an upper flange of the beam or a bracket connecting the beam and the column, and intersects at an intersection with the upper flange, The joint structure between a main structure and a brace according to claim 1, wherein a web stiffener connecting the upper flange and the lower flange from the intersection is provided on a side of the beam or the web of the bracket. The first fin stiffener and the gusset plate are welded,
The length of the first fin stiffener satisfies a welding length at which a shear strength at a welding portion between the first fin stiffener and the gusset plate is equal to or greater than an axial force acting on the first fin stiffener from the brace. The joint structure of a main structure and a brace according to claim 1 or 2, wherein the structure is a length. The brace is
Having a core material and a pair of restraining members disposed along both surfaces of the core material,
The pair of restraining members are each formed of a channel steel whose core material side is open, and a cement-based material filled in the channel steel,
On both surfaces of the core, reinforcing ribs projecting perpendicular to the surface and extending in the longitudinal direction of the core from both ends of the restraining member are provided, and the end of the brace is A buckling-restrained brace having a cross-sectional shape formed by a core material and two of the reinforcing ribs,
The core and the gusset plate are bolted together via a first splice plate, and the two reinforcing ribs and the first fin stiffener are bolted together via a second splice plate. A joint structure between the main structure and the brace according to any one of claims 1 to 3.   The number of bolts that join the core and the first splice plate, and the ratio of the number of bolts that join the reinforcing rib and the second splice plate, depending on the ratio of the thickness of the core and the reinforcing ribs The joint structure of the main structure and the brace according to claim 4, wherein the structure is set.   6. The end of the first fin stiffener that bends and shifts to the second fin stiffener when the pillar is an SRC pillar, is located at a position that does not interfere with the SRC pillar. 7. The joining structure of the main structure and the brace according to any one of the above.

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