JP6260554B2 - Column and beam joint structure - Google Patents

Description

  The present invention relates to a column-to-beam joint structure, and more particularly to a column-to-beam joint structure in which a column and an H-shaped steel beam are joined using a bracket.

In general, when the span of adjacent columns increases, in order to ensure the rigidity of the beam, the cross section of the H-shaped steel beam increases the web web thickness and reduces the web plate thickness (increases the web width-thickness ratio). Becomes efficient.
However, when the web width / thickness ratio is increased, the web may be buckled out of plane before the flange, and a predetermined yield strength or deformation performance may not be obtained. As means for preventing this, for example, as shown in Patent Document 1, a reinforcing method is proposed in which a horizontal stiffener parallel to the flange or a vertical stiffener orthogonal to the flange is installed.

  Patent Document 2 proposes an H-shaped steel with a protrusion formed by rolling a portion corresponding to a horizontal stiffener.

  On the other hand, Patent Document 3 proposes H-shaped steel in which the thickness of the web is different between the central portion of the web and the flange connecting portion for the purpose of reinforcing through holes such as equipment piping provided in the H-shaped steel beam. ing.

JP 2002-220873 A JP 61-162658 A JP 2011-202423 A

  It is considered that there is an effect of preventing out-of-plane buckling by installing a horizontal stiffener, a vertical stiffener, or a combination thereof as the buckling stiffening of the web. However, when welding horizontal stiffeners or vertical stiffeners to the web, bending or warping occurs due to the thermal effect during welding, and correction is necessary to ensure accuracy, and stress concentration due to welding residual strain becomes a problem. .

  Further, as disclosed in Patent Document 2, when a protrusion is attached to the central portion of the web, the gusset plate of the web portion is divided into two in the height direction in the bolt connection with the column or the adjacent beam, or in the plate thickness direction. However, there is a problem in that the steel plate is curved and is not sufficient in terms of yield strength and is difficult to manufacture.

  The H-shaped steel beam disclosed in Patent Document 3 is for the purpose of stiffening the beam through-hole, and is a web when an excellent bending moment is generated at the column-beam junction targeted by the present invention. No consideration has been given to out-of-plane buckling.

  The present invention has been made in order to solve the above-mentioned problems, and it is possible to provide a column-to-beam junction structure that can be joined with a simple structure and has no problems due to welding residual strain or problems in terms of strength. The purpose is to get.

(1) The column-beam joint structure according to the present invention is a column-beam joint structure that joins a column and an H-shaped steel beam using a bracket, and the bracket has an H-shaped steel having a web and a flange. The H-shaped steel has at least the web formed integrally by rolling, and has a thick web portion thicker than the thickness of the central portion in the height direction of the web at the connection portion of the web with the flange. It is characterized by having.

(2) Further, in the above (1), the H-shaped steel beam has a constant web thickness, and the thickness of the central portion of the bracket is the same as the web thickness of the H-shaped steel beam. It is characterized by being set to.

(3) Further, in the above-described (1) or (2), the bracket has a lower plate thickness t _{w1 at} the center in the web height direction and a lower plate thickness t _{w2 at the} web thick portion. It is characterized by satisfying the formula.
t _w2 / t _w1 ≧ 0.7φ + 2.5
Where φ = d ₁ / d
Where d _{1 is} the height of the web center
d: Web height

(4) Further, in any of the above-described (1) to (3), the joint portion between the pillar and the bracket is continuously attached by attaching a contact plate to a central portion in the web height direction of the bracket. Partial penetration welding, and correspondingly, the plate and the center of the web are fillet welded.

  In the joining structure of a column and a beam in the present invention, when the column and the H-shaped steel beam are joined using a bracket, the bracket is made of H-shaped steel having a web integrally formed by rolling, and the H-shaped steel Since the steel has a thick web portion thicker than the thickness of the central portion in the height direction of the web at the connection portion of the web with the flange, it effectively prevents out-of-plane buckling occurring in the web. Is possible. Since the thick portion and the thin portion, which are the web portions of the bracket, are integrally formed by rolling, there are no manufacturing problems such as welding work such as stiffeners, materials, and warpage or bending due to welding.

It is explanatory drawing of the junction structure of the pillar which concerns on one embodiment of this invention, and a beam. It is explanatory drawing of the bracket used for the joining structure of the pillar which concerns on one embodiment of this invention, and a beam. It is arrow AA 'sectional drawing of FIG. It is explanatory drawing of the joining method of the bracket and a prism in the joining structure of the pillar which concerns on one embodiment of this invention, and the prism (the 1). It is explanatory drawing of the joining method of the bracket and the prism in the joining structure of the pillar which concerns on one embodiment of this invention, and a prism (the 2). FIG. 6 is a cross-sectional view taken along the line CC ′ in FIG. 5. FIG. 6 is a cross-sectional view taken along the line DD ′ in FIG. 5. It is arrow BB 'sectional drawing of FIG. It is explanatory drawing of the joining method of the bracket and H-shaped beam in the joining structure of the pillar and beam which concerns on one embodiment of this invention. FIG. 10 is a cross-sectional view taken along the line EE ′ of FIG. 9. It is explanatory drawing of the calculation method of buckling strength in the conventional stiffener stiffening method. It is explanatory drawing of the calculation method of the buckling strength in the joining method of the column and beam using the bracket of this invention.

As shown in FIG. 1, the column-beam junction structure according to the present embodiment is a column-beam junction structure in which a prism 1 and an H-shaped steel beam 3 are joined using a bracket 5, and the bracket 5 is rolled. It consists of the H-section steel integrally formed by. As shown in FIG. 2, the H-shaped steel constituting the bracket 5 has a web thick portion 7 b that is thicker than the thickness of the central portion 7 a in the height direction of the web 7 at the connection portion of the web 7 with the flange 9. ing.
The H-shaped steel in which the thickness of the web 7 differs between the central portion 7a in the height direction and the thick web portion 7b is the same as the stiffening by the lateral stiffener 23 in the conventional example by sufficiently increasing the thickness of the flange connecting portion. It is thought that the effect of can be obtained.
Details of this point will be described later.

The prism 1 and the bracket 5 are joined by welding, and the bracket 5 and the H-shaped steel beam 3 are joined by bolts.
As shown in FIG. 4, the welding of the prism 1 and the bracket 5 corresponds to the height of the web center portion 7 a, has the same width as the backing metal used in assembly welding, and has the same shape as the web 7. The patch plate 11 having the groove is welded to the web 7 side by fillet welding. With the contact plate 11 welded, the end of the bracket 5 is brought into contact with the prism 1 as shown in FIG. 5, and as a result, as shown in FIG. 6 and FIG. Partial penetration welding is possible.

  As shown in FIG. 5, the welding of the flange 9 and the diaphragm 13 of the prism 1 can be a normal complete penetration welding by providing a scallop 15 on the web 7 at the connection portion with the flange 9. Or it is also possible to employ | adopt the non-scallop method which does not provide a scallop.

  As shown in FIG. 8, the H-shaped steel beam 3 includes a beam web 3a and a beam flange 3b. The thickness of the beam web 3 a is constant, and the thickness of the beam web 3 a is set to be the same as the thickness of the central portion 7 a in the bracket 5. Such joining of the H-shaped steel beam 3 and the bracket 5 is connected using a gusset plate 19. When the shearing force is small, the same joining method as usual can be performed using only the web center portion 7a.

  In addition, when the shearing force is large and the height of the joining portion is required, as shown in FIGS. 9 and 10, the T-shaped filler plate 17 is used, and the vertical side of the T-shape is the central portion 7 a of the bracket 5. The gusset plate 19 is inserted so as to be disposed, and the gusset plate 19 is disposed on the filler plate 17 so as to include the web thick portion 7b of the bracket 5 and joined by the bolts 21, so that the gusset plate 19 is connected without being divided. It becomes possible to do.

Next, a preferable relationship between the plate thickness t _w1 of the central portion 7a in the height direction of the web 7 and the plate thickness t _w2 of the web thick portion 7b in the bracket 5 will be described.
Although bending and shearing force are generated at the end of the H-shaped steel beam 3, the bending is excellent in general beam length, and the influence of bending stress is closer to the flange connection part of the web 7. Here, the buckling strength due to bending is simply considered here.

FIG. 11 is an explanatory view of a method for calculating the buckling strength in the conventional stiffener stiffening method. FIG. 11 (a) is a side view of the column beam joint, and the H-shaped steel beam 3 is joined to the prism 1. The beam web 3 a of the H-shaped steel beam 3 is stiffened by a lateral stiffener 23. FIG. 11B is a cross-sectional view of the vicinity of the beam-column joint, with the thickness and length of each part added, and FIG. 11C shows the boundary condition of the part indicated by the broken line in FIG. It is explanatory drawing.
As shown in FIG. 11 (b), the height of the beam web 3a d, the distance from the beam flange 3b to the horizontal stiffener 23 of d _2, the transverse stiffener 23 and beam web 3a sandwiched by horizontal stiffener 23 Height D ₁ and the thickness of the beam web 3a as t _w1 and assuming that the lateral stiffener 23 has sufficient rigidity in the range of the length d from the column, the panel portion on the flange side of the lateral stiffener 23 (FIG. 11 (a The buckling strength in FIG. 11 (c) can be approximated by the following equation (1) as a compression + bending buckling strength formula with a four-turn rotation end.

FIG. 12 is an explanatory diagram of a method for calculating the buckling strength in the method of joining the prism 1 and the beam using the bracket 5 of the present invention. FIG. 12 (a) is a side view of the beam-column joint, and FIG. ) Is a cross-sectional view of the bracket 5 and is a diagram in which the thickness and length of each part are added, and FIG. 12C is an explanatory diagram of the boundary condition of the part indicated by the broken line in FIG.
As shown in FIG. 12 (b), the height of the web 7 d, d ₂ the length of the web the thick portion 7b, d ₁ the length of the central portion 7a, the thickness of the central portion 7a t _w1, web Assuming that the thickness of the thick portion 7b is t _w2 and the portion corresponding to the panel portion is a thick panel portion as in the case of the conventional example shown in FIG. 11, the buckling strength is three-side rotation. The buckling strength formula of the end and free side can be approximated by the following formula (2).

Assuming that the buckling strength of the portion corresponding to the panel portion of the present invention shown in FIG. 12 is more than the buckling strength of the stiffener-installed panel portion shown in FIG. The thickness ratio (t _w2 / t _w1 ) of the central portion 7a can be expressed as follows from the above equations (1) and (2).
σ _cr2 ≧ σ _cr1
t _w2 / t _w1 ≧ (k ₁ / k ₂ ) ^1/2 ≒ 0.7φ + 2.5
Where φ = d ₁ / d
Where d _{1 is} the height of the central portion 7a
d: Web height

Therefore, for example, assuming that the height of the central portion 7a in the bracket 5 is 1/3 of the total height, by setting t _w2 > 2.73 _tw1 , it is possible to obtain a buckling strength equivalent to that of the conventional stiffener installation.

In the above embodiment, the joining portion between the prism 1 and the bracket 5 is the continuous partial penetration welding by attaching the contact plate 11 to the central portion 7a in the height direction of the web 7 of the bracket 5. A shear plate that protrudes toward the bracket 5 may be attached to the column side, and the shear plate and the bracket 5 may be bolted together.
Moreover, in said embodiment, although the example which bolt-joins the bracket 5 and the H-shaped steel beam 3 using the gusset plate 19 was shown, you may join both by welding.

  In the present embodiment, when the prism 1 and the H-shaped steel beam 3 are joined using the bracket 5, an H-shaped steel integrally formed by rolling is used as the bracket 5, and the H-shaped steel is a flange in the web 7. Since the web thick portion 7b is thicker than the thickness of the central portion 7a in the height direction of the web 7 at the connection portion with the web 9, it is possible to efficiently prevent out-of-plane buckling occurring in the web 7. It becomes possible. Since the thick part and thin part which are the webs of the bracket 5 are integrally formed by rolling, there are no manufacturing problems such as welding work such as stiffeners, materials, and warping or bending due to welding.

In addition, the H-section steel having the web thick portion 7b is used for the bracket 5 and a method for determining the cross-sectional shape of the bracket 5 from the buckling strength formula corresponding to the generated bending stress distribution is proposed. Sheet thickness can be calculated.
Furthermore, since the contact plate 11 is attached to the central portion 7a of the bracket 5 at the joint portion of the bracket 5 made of H-shaped steel having the pillars and the web thick portion 7b, the bracket 5 is continuous in the height direction. Partial penetration welding can be performed, and efficient construction becomes possible.
In addition, the joint portion with the bracket is a continuous partial penetration welding by attaching a contact plate to the central portion of the bracket in the web height direction, and the corresponding plate and web central portion are fillet welded, An efficient shearing force can be transmitted from the thick part to the thin part.

In the above description, the prism 1 is exemplified as the pillar. However, the pillar is not limited to the prism, and includes a cylinder. In this case, a shear plate that protrudes toward the bracket 5 is attached to the pillar. You may do it.
In the above-described embodiment, the H-shaped steel constituting the bracket 5 is exemplified by one integrally formed by rolling. However, the bracket of the present invention is not limited to this, and at least the web is integrally formed by rolling. It may be a welded and assembled H-section steel formed by welding the flange to the web.

DESCRIPTION OF SYMBOLS 1 Square column 3 H-shaped steel beam 3a Beam web 3b Beam flange 5 Bracket 7 Web 7a Center part 7b Web thick part 9 Flange 11 Pad 13 Diaphragm 15 Scallop 17 Filler plate 19 Gusset plate 21 Bolt 23 Horizontal stiffener

Claims (5)

A column-to-beam joint structure that joins a column and an H-shaped steel beam using a bracket,
The H-shaped steel beam has a constant web thickness,
The bracket is made of an H-section steel having a web and a flange. At least the web is integrally formed by rolling, and the H-section steel is centered in the height direction of the web at a connection portion of the web with the flange. It has a thick web thick portion than the thickness of the parts, the junction structure of columns and beams, wherein the thickness of the central portion is set to the same thickness and web thickness of the H-shaped steel beam. A column-to-beam joint structure that joins a column and an H-shaped steel beam using a bracket,
The bracket is made of an H-section steel having a web and a flange. At least the web is integrally formed by rolling, and the H-section steel is centered in the height direction of the web at a connection portion of the web with the flange. have a thick web thick portion than the thickness of the part,
The bracket has a column-beam joint structure in which the plate thickness t _w1 of the center portion in the height direction of the web and the plate thickness t _w2 of the web thick portion satisfy the following formula .
t _w2 / t _w1 ≧ 0.7φ + 2.5
Where φ = d ₁ / d
Where d _{1 is} the height of the web center
d: Web height A column-to-beam joint structure that joins a column and an H-shaped steel beam using a bracket,
The bracket is made of an H-section steel having a web and a flange. At least the web is integrally formed by rolling, and the H-section steel is centered in the height direction of the web at a connection portion of the web with the flange. have a thick web thick portion than the thickness of the part,
The joint between the column and the bracket is a continuous partial penetration welding by attaching a contact plate to the central portion of the bracket in the web height direction, and the corresponding plate and web central portion are fillet welded. Column-beam joint structure characterized by 2. The column-to-beam joint according to claim 1, wherein the bracket has a thickness t _{w1 at} a center portion in the height direction of the web and a thickness t _{w2 at the} web thick portion satisfying the following expression. Construction.
t _w2 / t _w1 ≧ 0.7φ + 2.5
Where φ = d ₁ / d
Where d _{1 is} the height of the web center
d: Web height   The joint between the column and the bracket is a continuous partial penetration welding by attaching a contact plate to the central portion of the bracket in the web height direction, and the corresponding plate and web central portion are fillet welded. The column-beam junction structure according to any one of claims 1, 2, and 4.