JP2005240422A - Beam-column joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a joint structure having excellent earthquake resistance by which square steel pipe columns of various sizes are fabricated with high processing accuracy by simple processing works at a low cost. <P>SOLUTION: A plurality of square steel pipes 11, 12, 13, 14 are unified by fixing their pipe walls together to form a square pipe-shaped body 1 which constitutes a column. A web 21 of a beam 2 having an H-shaped cross section is joined to an outer surface of a pipe wall of the square pipe-shaped body at the part where the pipe walls of the square steel pipes abut on each other. The pipe walls of the square steel pipes are fixed together by means of a fastening member 4 like a bolt and of welding, and the insides of the square steel pipes are filled with a concrete when needed. The welding is carried out in a manner that the gaps, which are formed at the abutting sections of the square steel pipes by abutting round corners of the square steel pipes, are filled with a weld metal, whereby fitting of the beam is facilitated. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a steel beam-structured column-beam joint provided with a column member made of a square steel pipe and a beam member made of an H-shaped cross-section member, and more particularly to a structure suitable for a building structure requiring earthquake resistance.

  Square steel pipe columns can secure large rigidity even when the plate thickness is thin, and it is easy to mount fireproof coverings and crosspiece brackets. Therefore, H-steel and BOX columns can be used as steel structure columns for medium- and low-rise buildings. It is often used for.

  In the column-beam joint where an H-shaped beam is combined with a square steel pipe column, the position facing the H-shaped web is hollow, so the out-of-plane rigidity of the column tube wall (also called the column flange) is low, As a result, the joint efficiency of the attachment portion is reduced.

  In the present invention, the joint efficiency means “a ratio of actual stress transmission with respect to a case where the stress transmission capability of the beam-column joint is perfect”. To be exact, it is the “web joint efficiency” of the H-shaped steel beam, and “the total plasticity of the web when the entire cross-section of the web is valid for the moment that the web actually bears when the beam is sufficiently plasticized. It is defined as “ratio to moment”.

  That is, it is an index that expresses that the web is not necessarily in a completely plastic state due to the out-of-plane deformation of the column wall of the column or the presence of scallops in the column-beam joint portion with a hollow cross-section column that is often used in practice.

  Web joint efficiency is approximately 1/2 of the inverse of the column width / thickness ratio (column outer diameter / column tube thickness) when the yield point of the column and beam web are equal and the beam height is equal. It is known that it is proportional to the power (Non-patent Document 1). Accordingly, if the column width thickness ratio is reduced to increase the out-of-plane rigidity, the joint efficiency is also improved.

  FIG. 5 shows an example of a column beam joint. The figure shows a partial cross-sectional view of a joined portion in which a beam 200 made of H-shaped steel is joined to a square steel tube column 400. The square steel tube column 400 at the beam-to-column joint is formed by upper and lower square steel tube columns 100a via diaphragms 300a and 300b. , 100b.

  In order to improve the joint strength and earthquake resistance in the column beam joint that attaches the H-shaped beam to the square steel pipe column, the joint part is a method to increase the out-of-plane rigidity of the column pipe wall in order to increase the joint efficiency of the attachment part. It has been proposed to use a thick square steel pipe or to provide an inner diaphragm inside the steel pipe and to arrange a vertical stiffener or the like at a position facing the web.

  Patent Document 1 relates to a column-to-beam joint of a square steel pipe column. A thick seamless steel pipe is hot-rolled into the steel pipe column to be a joint, and the thickness is higher than the upper and lower columns of the column-beam joint. A beam-to-column joint that has a simple structure and high strength is described by using a thick one that has rounded corners on the four corners.

  Patent Document 2 relates to a square steel pipe having a beam-column joint having excellent joint efficiency. When two groove steels 500a and 500b are made into a square steel pipe by butt welding, a backing material 600 for welding is formed on a portion to be a joint. A rectangular steel pipe is described in which an inner diaphragm 700 is attached and a vertical stiffener is attached at a position opposite to the H-shaped steel web to be a beam to improve joint efficiency (FIG. 6).

  Patent Document 3 relates to a method of manufacturing a rectangular steel pipe in which an inner diaphragm is provided at a joint portion in order to reinforce a column beam joint and the like, and when the inner diaphragm 700 and the channel steel 100 are welded by electroslag welding. It is described that an inner diaphragm is formed so as to prevent the molten metal from flowing out of the weld hole (FIG. 7).

Patent Document 4 relates to a structure of a joint portion between a concrete-filled steel pipe column and a beam member. In order to increase the rigidity of the joint portion, a reinforcing member provided in a portion where the steel pipe column serves as a joint position with the beam member is applied to concrete. A concrete-filled steel pipe that is fixed in an embedded state is described.
JP-A-8-302899 JP-A-11-124907 JP 2002-54231 A JP-A-9-125518 Published by the Architectural Institute of Japan, “Current Status of Research on Mechanical Properties of Steel Structure Joints”, 1993, p. 80

  However, since the square steel pipe described in Patent Document 1 is manufactured by hot-rolling a thick seamless steel pipe, its dimensions are restricted by the product dimensions of the thick seamless steel pipe, and the applied building structure is limited. . In the methods described in Patent Documents 2 and 3, since the inner diaphragm is provided inside the steel pipe, the manufacturing process of the square steel pipe is complicated, the product cost is high, and labor for securing the processing accuracy is required.

  Therefore, an object of the present invention is to provide a structure of a joint portion that can manufacture square steel pipe columns having various dimensions with high processing accuracy at low cost by simple processing, and is excellent in earthquake resistance.

The object of the present invention can be achieved by the following means.
1 Column-beam joint used in a building structure, wherein a column is a rectangular tubular body in which a plurality of rectangular steel pipes are integrated by fixing their tube walls, and the beam of the beam is A beam-to-column connection part characterized by being joined along a contact part of the square steel pipe in a pipe wall of the square tubular body.

  According to the present invention, since a column beam joint having excellent joint efficiency when a beam is attached can be obtained, the earthquake resistance of the building can be improved, which is extremely useful industrially.

  The present invention is characterized in that a rectangular tubular body formed by combining a plurality of rectangular steel pipes is used as a steel pipe column to which a beam of a column beam joint is attached.

  FIG. 1 is a schematic cross-sectional view illustrating the structure of a beam-column joint according to an embodiment of the present invention. In the figure, 1 is a rectangular tubular body, and 11, 12, 13, and 14 constitute a rectangular tubular body 1. 2 is a beam, 21 is a web portion of 2 beams, 3 is a welded portion for joining 11, 12, 13, and 14 square steel tubes, and 4 is a fastener for 11, 12, 13, and 14 square steel tubes. A fastening member is shown.

  When the rectangular tubular body 1 is constituted by a plurality of rectangular steel pipes 11 to 14, a portion where the web portion 21 of the beam 2 is attached to the rectangular tubular body 1 is a butt portion of the rectangular steel pipes 11 to 14 (in FIG. 1, a welded portion 3). ) To determine the dimensions of the square steel pipes 11-14.

  When using what is marketed as a square steel pipe, a hot-formed square steel pipe having a side length of 150 to 250 mm or less can be used (for example, JFE Steel trade name JFE Kaku Hot), and the side length of the square tubular body 1 is set to 300 mm or more. be able to.

  After fixing the square steel pipes 11 to 14 with the fastening members 4 such as bolts, the butt portions are welded. In order to facilitate the attachment of the beam, the welding is performed so that the gap formed by the butting of the corner R portions of the square steel pipes 11 to 14 is filled with the weld metal.

  FIG. 2 is a perspective view showing the structure of a beam-column joint according to another embodiment of the present invention, in which 5a is an upper column of a building structure, 5b is a lower column of the building structure, and 6a is a rectangular tubular body. A through-diaphragm attached to the upper surface, 6b denotes a through-diaphragm attached to the lower surface of the joint, and t denotes a plate thickness of the square steel pipe. The other reference numerals are the same as those in FIG.

  FIG. 3 shows the structure of the rectangular tubular body 1 used for the beam-column joint of FIG. 2, and slits for welding the square steel pipe are machined in the through diaphragms attached to the upper and lower parts of the square steel pipe. . The slit is preferably a cruciform shape so that four square steel pipes can be welded to the diaphragm, and the width b of the slit is preferably about 1.5 times the thickness of the square steel pipe. The slit length is preferably a length obtained by subtracting twice the plate thickness of the rectangular steel pipe from the side length B of the rectangular tubular body 1.

In the case of constructing the joint 1 in FIG. 2, the following steps are preferable.
1. Combination process of square steel pipes Four square steel pipes 11 to 14 having a side length of 250 mm are combined so as to form a square and welded to form a square tubular body 1. When a hot-formed square steel pipe (for example, JFE Steel product name JFE Kaku Hot) is used as the square steel pipes 11 to 14, the corner R portion is smaller than that of the cold-formed square steel pipe, so that the welding operation can be simplified.

The length of the square steel pipe is the length obtained by subtracting the diaphragm thickness from the beam when the beam flange outer surface is aligned with the diaphragm outer surface.
2. Groove processing of a rectangular tubular body The groove processing for attaching a diaphragm to the upper and lower ends of a rectangular tubular body is performed.
3. Diaphragm attachment process to a rectangular tubular body After welding by aligning the ends of the rectangular steel pipe with slits provided in the diaphragm, the upper and lower ends of the rectangular tubular body are welded to the diaphragm.

4. Mounting process of beam to square tubular body H-shaped cross section beam is attached to the rectangular tubular body by welding and bolt connection. The flange and diaphragm of the H-shaped cross section beam are welded, and the web and the rectangular tubular body are welded or bolted together.

  FIG. 4 is an external view showing the structure of a beam-column joint according to another embodiment of the present invention. FIG. 4A shows the total length of a column of a building structure with a rectangular tubular body 5 made of four rectangular steel pipes. Shows the case. The column-beam joint according to the present invention has a high moment of inertia in section compared with a case where a single square steel pipe is used as a column. Therefore, when the rectangular tubular body 5 of the column-beam joint is extended to the full length of the column. It becomes possible to reduce the cross-sectional dimension of the column.

  FIG. 4B shows a case in which concrete 7 is filled in the rectangular steel pipe constituting the rectangular tubular body 5. When filling the concrete 7, it is preferable to provide a hole for communicating a plurality of rectangular steel pipes because a rectangular tubular body with higher rigidity can be obtained. In the inner diaphragm type, a perforated inner diaphragm is used, and the filling property is excellent as compared with the case of filling concrete.

  In the present invention, the number of rectangular steel pipes constituting the rectangular tubular body of the column beam joint is not particularly limited. The number of rectangular steel pipes can be selected as appropriate so that the moment from the web of the H-shaped cross-section beam can be efficiently transmitted to the rectangular tubular body. For example, the side length of the rectangular tubular body is four rectangular steel pipes. It is also possible to form a square tubular body with 16 square steel pipes.

  Moreover, it is also possible to make the shape of a square steel pipe into a rectangular cross section according to the attachment direction of the beam in a junction part. For example, when two beams are attached only in the horizontal direction, a rectangular tubular body is constituted by two rectangular steel pipes having a rectangular cross section.

The figure which shows the column beam junction which concerns on one Embodiment of this invention. The figure which shows the column beam junction which concerns on one Embodiment of this invention. The figure which shows the structure of the square tubular body of the column beam junction part which concerns on one Embodiment of this invention. The figure which shows the column beam junction part structure which concerns on other embodiment of this invention. Conventional example Conventional example Conventional example

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Square tubular body 11, 12, 13, 14 Square steel pipe 2 Beam 21 Web part 3 Welded part 4 Fastening member 5a Upper pillar 5b Lower pillar 6a Through diaphragm 6b Through diaphragm 7 Concrete 100a, 100b Square steel pipe pillar 200 Beam 300a, 300b Diaphragm 400 Square steel pipe column 500, 500a Channel steel 600 Backing material for welding 700 Inner diaphragm

Claims (1)

A column-beam joint used for a building structure, wherein the column is a rectangular tubular body in which a plurality of rectangular steel pipes are integrated by fixing their tube walls, and the beam of the beam is the above-mentioned A beam-to-column connecting portion characterized by being joined along the abutting portion of the rectangular steel pipe in the tube wall of the rectangular tubular body.

Images