JP2015161148A - Buckling restraining brace joint structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a buckling restraining brace joint structure that enables a brace core of a buckling restraining brace to correspond to a structural core of a structural skeleton, without complication of detailing of a column-beam-brace joint.SOLUTION: In a buckling restraining brace joint structure, a buckling restraining brace 20 is joined to a brace joint metal 3 that is joined to a steel column 1 and a steel beam 2. A joint between the steel column 1 and the steel beam 2, which is a corner part for joining the buckling restraining brace 20, is pin-joined in such a manner that the beam 2 is bolt-joined to a gusset plate 4 protruding from the column 1. An intersection point, at which a brace core of the buckling restraining brace 20 and a column core of the column 1 cross each other, corresponds to an intersection point at which the column core and a beam core cross each other.

Description

  The present invention relates to a joint structure of a buckling-restrained brace in a house, an apartment house, or other steel structure building.

  Conventionally, when a brace that bears compressive force and tensile force, such as a buckling-restrained brace, is joined to the structural frame, the buckling-restraining brace intersects the pin joint between the steel column and the beam. The bolt joint position is greatly decentered from the column core. Further, since the buckling-restraining brace also acts on the compression side, the joint portion to the structural housing has a complicated structure for reinforcement.

Japanese Patent No. 04044483 Japanese Patent Laid-Open No. 10-266337 JP 2010-281165 A JP 2012-172490 A

In general, in consideration of the influence on the structural housing, it is desirable to join the members without decentering from the structural core as much as possible.
In addition, the buckling-restrained brace bears not only the tensile force but also the compressive force, so if a buckling-restraining brace is joined to the joint to the column / beam with a normal gusset plate, buckling may occur in the out-of-plane direction. There is sex. In order to prevent this, a reinforcing plate such as a rib plate is required, and the accommodation of the column / beam / brace joint is complicated. In particular, in the case of a bi-directional brace frame, there is a case where it is necessary to increase the column size in the above-described conventional technique in which the bolt joint position at the beam end is greatly decentered.

  An object of the present invention is to provide a buckling-restrained brace joint structure in which the brace core of the buckling-restrained brace can be matched with the structural core of the structure without complicating the fitting of the joints of the columns, beams, and braces. Is to provide.

The joint structure of the buckling restraint brace of the present invention is a joint structure of a buckling restraint brace in which a buckle restraint brace is joined to a brace joint hardware joined to a steel column and beam.
A brace of the buckling restrained brace is a joint between a steel column and a beam that serves as a corner for joining the buckling restrained brace and a pin joint that bolts the beam to a gusset plate protruding from the pillar. The intersection of the core and the column core of the column is made to coincide with the intersection of the column core and the beam core of the beam.

  In this configuration, the junction between the column and the beam, which is the corner to join the buckling-restrained brace, is a pin connection, but by pulling the gusset plate out of the column and shifting the bolt connection position at the beam end, -It is possible to match the intersection where the brace core of the buckling restrained brace and the column core of the column intersect with the intersection where the column core and the beam core intersect without being obstructed by the bolt joint portion of the beam. This makes it possible to match the brace core of the buckling-restrained brace with the structural core of the structural frame without complicating the accommodation of the column / beam / brace joint.

In the present invention, the gusset plate may be provided with a reinforcing plate inclined along the inclination of the buckling restraint brace.
In the joint structure in which the beam is bolted to the gusset plate protruding from the column as described above, the shearing force at the beam end acts eccentrically from the column core, and the effect of this effect is the calculation of the column cross section. It is necessary to evaluate appropriately. However, when a reinforcing plate inclined along the inclination of the buckling-restraining brace is provided on the gusset plate, the amount of protrusion of the gusset plate is smaller than that of a general configuration in which a reinforcing plate is provided vertically. it can. That is, the distance from the column of the joint portion of the beam can be made as small as possible. Therefore, the additional bending moment accompanying the eccentricity can be minimized, and an increase in the size of the column can be avoided.

In this invention, the brace joint hardware has an inclined brace joint portion having a cross-sectional shape extending along the inclination direction of the buckling restraint brace and having a web and a flange, and the buckling restraint brace has a cross section at an end portion. An H-shaped H-shaped joint is provided, and the slanted brace joint of the brace joint hardware and the H-shaped joint of the buckling-restrained brace are joined together by a flange of the slanted brace joint and a flange of the H-shaped joint. It is also possible to use a splice plate disposed across the two webs for the joining, and this splice plate may have reinforcing ribs.
In the case of this configuration, since the splice plate has the reinforcing rib, it is possible to increase the reinforcing effect against the out-of-plane buckling at the joint portion of the buckling restrained brace.

In this invention, the beam may be wider than the column, the gusset plate may have a cross-sectional H shape having reinforcing plates at upper and lower ends, and the width of the reinforcing plate may be narrower than the width of the beam. .
In the case of a bi-directional brace frame in which the brace bears loads in both the compressive direction and the tensile direction, there are places where the beam width dimension is larger than the column size. Even when the beam width dimension is large as described above, since the reinforcing plate of the gusset plate is usually set to the same width as the beam width dimension, it becomes difficult to weld the column of the gusset plate to the column. However, even if the beam is wider than the column as described above, and the gusset plate has a cross-sectional H shape having reinforcing plates at the upper and lower ends, the width of the reinforcing plate is narrower than the width of the beam, For example, by setting the same dimensions as the pillar, welding of the gusset plate to the pillar can be easily performed.

  The buckling restrained brace joining structure of the present invention is the buckling restrained brace joining structure in which the buckling restrained brace is joined to the brace joint hardware joined to the steel column and beam. The joint between the steel column and the beam, which is a corner, is a pin joint that bolts the beam to a gusset plate protruding from the column, and the brace core of the buckling-restrained brace and the column core of the column Since the intersection point of the column and the beam core of the beam intersects with each other, the brace core of the buckling-restrained brace is attached to the structural frame without complicating the fitting of the column / beam / brace joint. Can match the structure core.

It is a perspective view of the junction structure of a buckling restraint brace concerning one embodiment of this invention. FIG. 2 is a horizontal sectional view of a column / beam joint in FIG. 1. (A) is the partial front view of the structural housing to which the joining structure is applied, (B) is the partial plan view. It is a partial front view of an example of the other structural housing to which the joint structure is applied. (A) is a front view of the brace joint part in the joint structure, and (B) is a plan view taken along the a-a ′ arrow in (A). 5A is a cross-sectional view taken along the line b-b ′ in FIG. 5A, FIG. 5B is a cross-sectional view taken along the line c-c ′, and FIG. 5C is a cross-sectional view taken along the line d-d ′. (A) is a plan view of the core material in the buckling restraint brace, (B) is a side view of the core material, (C) is a plan view of the width direction reinforcing steel material in the buckling restraint brace, and (D) is the seat. The front view of the restraint material in a bending restraint brace, (E) is sectional drawing of the restraint material.

  An embodiment of the present invention will be described with reference to FIGS. As shown in the perspective view of FIG. 1, the buckling-restrained brace joining structure is formed by joining a buckling-restraining brace 20 in an inclined posture to a brace joint hardware 3 joined to a steel column 1 and a beam 2. It is a junction structure.

  FIG. 3A shows a partial front view of a structural frame of a steel building to which this joining structure is applied, and FIG. 3B shows a plan view thereof. The steel structure building is, for example, a low-rise multi-storey apartment house. In this structural housing, a pair of buckling restraint braces 20 and 20 are arranged in a C shape, and the lower end of each buckling restraint brace 20 is joined to the brace fitting 3, and the upper end of each buckling restraint brace 20 is the beam 2. It is joined to the middle part. In addition, even if it is a structural housing | casing by which a pair of buckling restraint braces 20 and 20 are arrange | positioned in reverse C shape like FIG. 4, and the upper end of each buckling restraint brace 20 was joined to the said brace joining metal fitting 3, The first embodiment can be applied by adopting a configuration that is upside down.

  In FIG. 1, a joint portion between a steel column 1 and a beam 2 that serves as a corner portion for joining a buckling-restraining brace 20 is a pin joint in which the beam 2 is joined to a gusset plate 4 projecting from the column 1 with a bolt 5. It is said that. The gusset plate 4 is joined to the side of the column 1 by welding. The brace fitting 3 is also joined to the column 1 by welding. The gusset plate 4 and the brace fitting 3 are separate parts in the manufacturing process, but are combined parts welded to each other, and the combined parts are joined to the column 1 by welding.

  The intersection point where the brace core of the buckling restraint brace 20 and the column core of the column 1 intersect is made to coincide with the intersection point where the column core and the beam core of the beam 2 intersect. The column 1 is formed of a square steel pipe, and the beam 2 is installed with an H-shaped steel so that the flange portion is positioned up and down. As shown in a horizontal sectional view in FIG. 2, the beam 2 is wider than the column 1.

  The gusset plate 4 has an H-shaped cross section having reinforcing plates 4a and 4a at the upper and lower ends, and the width of the reinforcing plate 4a is set narrower than the width of the beam 2 as shown in FIG. Specifically, the width of the reinforcing plate 4a is set to be substantially the same as that of the pillar 1. The bolt 2 of the beam 2 to the gusset plate 4 extends from the web 4b of the gusset plate 4 to the web 2b of the beam 2, and a pair of splice plates 6 that sandwich the webs 4b and 2b from both sides are disposed. The two webs 4b and 2b are joined by a plurality of bolts 5 penetrating both the splice plates 6 and the webs 4b and 2b. Further, on both surfaces of the web 4 b of the gusset plate 4, reinforcing plates 7 inclined along the inclination of the buckling restrained brace 20 are provided by welding.

  The brace joint hardware 3 has an inclined brace joint portion 8 extending along the inclination direction of the buckling restrained brace 20. In FIG. 1, the inclined brace joint 8 has an inverted T-shaped cross section composed of a web 8a and a flange 8a below the web 8a. However, as shown in FIG. It may have a cross section.

  5A shows a front view of the joint between the inclined brace joint 8 and the buckling restrained brace 20, and FIG. 5B is a plan view taken along the line aa ′ in FIG. 5A. Indicates. At the end of the buckling restrained brace 20, an H-shaped joint 25 having an H-shaped cross section is formed. The inclined brace joint 8 on the side of the brace joint 3 and the buckling restrained brace 20 are joined to the flange 8a of the inclined brace joint 8 on the brace joint 3 side and the H-shaped joint 25 on the buckling restraint brace 20 side. The flange 8 is not joined, and is joined only between the web 8b of the inclined brace joint 8 and the web 25b of the H-shaped joint 25.

  That is, a pair of splice plates 9 and 9 are disposed to extend from the web 8b of the inclined brace joint 8 to the web 25b of the H-shaped joint 25 and sandwich the webs 8b and 25b from both sides. 9 and the webs 8b and 25b are joined to each other with a plurality of bolts 10 passing through the webs 8b and 25b, whereby the web 8b of the inclined brace joint 8 and the web 25b of the H-shaped joint 25 are obtained. It is joined. The splice plate 9 has reinforcing ribs 9a extending in the inclination direction of the buckling restrained brace 20, and the entire cross section is T-shaped. As described above, the reinforcing rib 9a extending in the inclination direction of the buckling restrained brace 20 is provided on the splice plate 9 that joins the inclined brace joint 8 and the buckling restraining brace 20 on the brace joint metal 3 side, thereby buckling. The reinforcement effect with respect to the buckling of the restraining brace 20 can be increased.

  6A, 6B, and 6C show a cross-sectional view taken along the line bb ′, a cross-sectional view taken along the line cc ′, and a cross-sectional view taken along the line dd ′ in FIG. . As shown in FIGS. 7A, 7B, 7C, 7D, the buckling-restraining brace 20 is formed along a plate-shaped core material 21 and both surfaces of the core material 21. It has a pair of constraining materials 22 and 22 arranged opposite to each other. The restraining material 22 is composed of a square steel pipe. The rectangular steel pipe of the restraining material 22 may be filled with a curable filler such as concrete. Both end portions of the core material 21 are widened portions that become the webs 25b of the H-shaped joint portion 25, and reinforcing plates 26 that serve as flanges of the H-shaped joint portion 25 are provided on both sides of the widened portion. Protrusions 24 for restraining displacement of the restraining material 22 are provided in the longitudinal intermediate portions of both surfaces of the core material 21, and engaging holes 28 for engaging the projections 24 are provided in the longitudinal intermediate portion of the restraining material 22. The upper and lower ends of the pair of restraining materials 22, 22 are connected by a width direction reinforcing steel material 23 extending in the brace longitudinal direction as shown in FIG. 6C. A plan view of the width direction reinforcing steel member 23 is shown in FIG. As shown in FIG. 6B, another reinforcing plate 27 straddling between both reinforcing plates 26 serving as a flange is joined to the H-shaped joint portion 25 of the buckling restrained brace 20.

  According to the joining structure of the buckling restrained brace having this configuration, the steel column 1 and the beam 2 which are the corners to join the buckling restrained brace 20 are pin joined by bolt joining. , And the beam 2 is bolted to the gusset plate 4 so that the bolted position at the beam end is separated from the column core. Thereby, the intersection where the brace core of the buckling restraint brace 20 and the column core of the column 1 intersect is made coincident with the intersection where the column core and the beam core intersect without being hindered by the bolt joint portion of the column / beam. . For this reason, the brace core of the buckling-restraining brace 20 can be made to coincide with the structural core of the structural frame without complicating the accommodation of the column 1, the beam 2, and the brace joint hardware 3.

  In the joint structure according to the present invention, the shearing force at the beam end acts eccentrically from the column core, but the effect of the effect depends on the cross section of the column 1. In this embodiment, the gusset plate 4 is provided with the reinforcing plate 7 that is inclined along the inclination of the buckling-restraining brace 20, so that the protruding amount of the gusset plate 4 is reduced, that is, the column of the joint portion of the beam 2. By reducing the distance from 1 as much as possible, the additional bending moment accompanying the eccentricity can be minimized, and an increase in the size of the column 1 can be avoided.

  In the case of a two-way braced frame in which a load in both the compression direction and the tensile direction is applied to the brace, there are places where the beam width dimension is larger than the column size. In this embodiment, the beam 2 is larger than the column 1 as described above. Since it is wide and the gusset plate 4 has a cross-sectional H shape with reinforcing plates 4a at the upper and lower ends, the width of the reinforcing plate 4a is narrower than the width of the beam 2, for example, approximately the same dimensions as the pillar 1, It is possible to easily weld the gusset plate 4 to the column 1.

DESCRIPTION OF SYMBOLS 1 ... Column 2 ... Beam 3 ... Brace metal fitting 4 ... Gusset plate 4a ... Reinforcement plate 4b ... Web 5 ... Bolt 7 ... Inclined reinforcement plate 8 ... Inclined brace junction 8b ... Web 9 ... Splice plate 9a ... Reinforcement rib 20 ... Buckling restrained brace 25 ... H-shaped joint 25b ... Web

Claims (4)

In the junction structure of buckling-restrained braces where a brace-restraining brace is joined to a brace joint hardware joined to a steel column and beam,
A brace of the buckling restrained brace is a joint between a steel column and a beam that serves as a corner for joining the buckling restrained brace and a pin joint that bolts the beam to a gusset plate protruding from the pillar. A junction structure for a buckling-restrained brace, characterized in that an intersection point between a core and a column core of the column is made to coincide with an intersection point between the column core and a beam core of the beam.   The joint structure of the buckling restraint brace according to claim 1, wherein the gusset plate is provided with a reinforcing plate that is inclined along the slope of the buckle restraint brace.   3. The buckling constrained brace joint structure according to claim 1, wherein the brace joint hardware extends along an inclination direction of the buckling constrained brace and has a cross-sectional shape having a web and a flange. The buckling-restraining brace has an H-shaped joint having an H-shaped cross section at an end, and joins the inclined brace joint of the brace joint hardware and the H-joint of the buckling-restrained brace. The flange of the inclined brace joint and the flange of the H-shaped joint are not joined with only the webs of both joints, and a splice plate disposed across the two webs is used for the joint. Bonding structure of buckling restrained brace in which splice plate has reinforcing ribs.   The junction structure of the buckling restrained brace according to any one of claims 1 to 3, wherein the beam is wider than the column, and the gusset plate has reinforcing plates at upper and lower ends. And a buckling-restrained brace joint structure in which the width of the reinforcing plate is narrower than the width of the beam.

Images