JPH061505U - Joint structure of reinforced concrete columns and steel beams - Google Patents

Abstract

(57) [Summary] [Purpose] To ensure the stress transmission between columns and beams,
In addition, a joint structure with good mechanical properties is provided. [Structure] Diaphragms 32, 32 are joined in parallel to the upper and lower ends of a rectangular steel pipe 30, and each diaphragm 32,
32 is made of a substantially square flat steel having a square opening 34 in the center, and the four corners of the square steel pipe 30 are almost inscribed at the midpoints of the respective sides, and the four corners of the opening 34 are square steel pipes. It is almost inscribed at the midpoint of each side of 30. Since the four corners 36 of the diaphragm 32 project outward from the outer peripheral surface of the rectangular steel pipe 30, the four corners 36 are fixed to the steel beam 20.
Can be connected to the flange 22 of the. Further, since the diaphragm 32 also projects inside the rectangular steel tube 30, the diaphragm 32 sufficiently functions as a stress transmitting member between the pillar and the beam.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a structure of a column-beam joint portion of a composite structure having a reinforced concrete column and a steel frame beam.

[0002]

[Prior art and its problems]

 Buildings such as office buildings, shopping centers, and warehouses have a structural type consisting of reinforced concrete columns and steel beams. This structural type is excellent in that it can have a long span and can streamline construction, but since it is used to assemble dissimilar structural members such as reinforced concrete and steel frames, these members are used. The stress transmission at the joint of is an important issue.

In Japanese Laid-Open Patent Publication No. 2-252832, there is provided a horizontal diaphragm and a beam bracket on the outer surface of a steel pipe covering a joint between a reinforced concrete column and a steel beam, and the steel beam is attached to the bracket. A joining structure is disclosed. On the other hand, in Japanese Patent Laid-Open No. 2-266036, etc., a pair of upper and lower diaphragms is provided on the inner peripheral surface of a steel pipe covering a joint between a reinforced concrete column and a steel frame beam, and a beam perpendicular to the outer peripheral surface of the steel pipe. A structure is disclosed in which a joint plate is provided so as to project and a steel frame beam is joined through the joint plate.

The joint structure of the reinforced concrete column and the steel frame beam is excellent in that the joint effect is large because the joint portion is covered with the steel pipe. However, in the former case, the diameter of the diaphragm is significantly larger than the column size, and since a tapered steel pipe is used at the joint, there are problems in terms of production and transportation. There is. On the other hand, in the latter case, the projection of the horizontal diaphragm is limited to the inner peripheral surface of the steel pipe that covers the joint, so when constructing with cast-in-place reinforced concrete columns, the method of supporting the column-beam joint is inconvenient. The construction method is limited, such as occurrence.

Further, in Japanese Unexamined Patent Publication No. 1-290844, a cross-shaped horizontal diaphragm, which covers a joint between a reinforced concrete column and a steel frame beam with a steel plate and is connected to upper and lower flanges of the steel frame beam, is formed from the above steel plate. A joint structure provided so as to project outward is disclosed. However, this joining structure complicates the working and assembling work of the steel plates, such as the horizontal diaphragm protruding from the steel plates covering the joints.

[0006]

[The purpose of the device]

 The object of the present invention is to ensure that the stress transmission between columns and beams is ensured at the joints between reinforced concrete columns and steel beams, and that the required yield strength can be secured, and that the joint structure has good mechanical properties. To provide.

[0007]

[Constitution of device]

 The present invention relates to a joint structure of a reinforced concrete column and a steel beam in which a reinforced concrete column and a steel beam are joined via a pair of upper and lower horizontal diaphragms, and the diaphragms are covered with a steel pipe or a steel plate. The part connected to the flange projects outward from the column outer peripheral surface, and these adjacent connecting parts project at least inwardly from the column outer peripheral surface at the intermediate part, and the diaphragm is It is characterized in that concrete filling holes and column reinforcing bar through holes are provided.

Further, the present invention is characterized in that vertical ribs are provided on both the flange connecting portions of the upper and lower diaphragms and the steel pipe or the steel plate.

[0009]

[Action]

 In the joint structure of the reinforced concrete column and the steel frame beam, the stress generated in the column or the steel frame beam is mutually and surely transmitted through the upper and lower diaphragms and the steel pipe or the steel plate surrounding the joint part. Further, the outer steel pipe or steel plate accurately restrains the concrete in the panel zone.

[0010]

【Example】

 Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a plan view of a joint between a reinforced concrete column and a steel beam according to the present invention, and FIG. 2 is a vertical side view taken along line II-II of FIG.

At the joint between the precast reinforced concrete column 10 containing the column main bar 12 and the steel beam 20, the height is equal to the length of the web 24 of the steel beam 20, and the cross section shape of the column 10 is made. Equal square steel pipes 30 are installed. The rectangular steel pipe 30 may be formed by welding a plurality of steel plates, and the shape thereof is not limited to the rectangular shape and is formed into a shape corresponding to the cross section of the column 10.

Diaphragms 32, 32 are joined in parallel at the upper and lower ends of the rectangular steel pipe 30, that is, at the positions where the upper and lower flanges 22 of the steel beam 20 are connected. Each diaphragm 32 is made of a substantially square flat steel having a square opening 34 at the center, and the four corners of the square steel pipe 30 are almost inscribed at the midpoints of the sides of the substantially square, and the opening is The four corners of 34 are almost inscribed at the midpoint of each side of the rectangular steel pipe 30.

As described above, since the four corners 36 of the diaphragm 32 project outward from the outer peripheral surface of the rectangular steel pipe 30, the four corners 36 can be connected to the flange 22 of the steel beam 20. Further, since the diaphragm 32 also projects inside the rectangular steel pipe 30, the diaphragm 32 sufficiently functions as a stress transmitting member between columns and beams.

The size of the diaphragm 32 is determined by the size of the reinforced concrete column 10 and the steel beam 20, etc. However, if each side of the diaphragm 32 is not small enough to circumscribe the four corners of the rectangular steel pipe 30, the size of the diaphragm 32 will be small. The diameter is too large and inappropriate.

On the other hand, the four corners of the opening 34 of the diaphragm 32 do not necessarily have to be inscribed in each side of the rectangular steel pipe 30, and the size as a concrete filling hole formed by each side of the opening 34 is ensured. It is sufficient that the diaphragm 32 can secure a lateral width that functions as a stress transmitting member. Generally, as long as the four corners of the opening 34 are inscribed in each side of the rectangular steel pipe 30, the stress between the columns and the beams is sufficiently transmitted.

The diaphragm 32 is formed with a small hole for inserting the column main bar 12. Further, ribs 40 are vertically welded between the four corner portions 36, 36 of the upper and lower diaphragms 32, 32, which face each other in the vertical direction, in contact with the outer peripheral portion of the steel pipe 30.

The steel beam 20 made of H-shaped steel is joined to the sides of the square steel pipe 30 from four sides of the column 10. In this embodiment, the four corners 36 of the upper and lower diaphragms 32 and the upper and lower flanges 22 of the steel beam 20 are butted. It is bolted through the flange plate 42. Further, the web 24 of the steel beam 20 is bolted to the rib 40 via the web plate 44.

For joining the steel beam 20 to the square steel pipe 30 and the upper and lower diaphragms 32, various forms can be adopted. For example, the upper and lower diaphragms 32, 32 are provided separately at a height position that allows for a construction clearance when constructing the steel beam 20, and the steel beam 20 is placed between the four corners 36, 36 of both die diaphragms 32, 32. It may be fitted and bolted. In this case, the rib 40 is unnecessary.

In the present invention, the steel part is manufactured in advance in a factory or the like. That is, after joining the rectangular steel pipe 30 and the upper and lower diaphragms 32, the ribs 40 are welded. Then, in the case of the full PC material, the pillar 10 and the steel portion are integrally cast into concrete. At the site, after the reinforced concrete columns 10 have been installed at a predetermined position, the ends of the steel beam 20 may be brought in from four directions and joined to the upper and lower diaphragms 32.

On the other hand, when the pillar 10 is made of half PC material, the steel portion including the upper and lower diaphragms 32 is placed on the pillar head of the reinforced concrete pillar 10 that has been built, and then the steel beam 20 is mounted. After joining the upper and lower diaphragms 32 and the ribs 40, concrete is poured from the opening 34 of the diaphragm 32 into the panel zone. In the panel zone, since the column main bars 12 and the like are only buried, the concrete is smoothly filled.

In the joint structure of the reinforced concrete column and the steel frame beam, the stress of the column 10 and the steel frame beam 20 which are joined together is accurately transmitted to each other through the upper and lower diaphragms 32 and the rectangular steel pipes 30. Further, the rectangular steel pipe 30 surrounding the column outer periphery accurately restrains the concrete in the panel zone.

That is, the bending moment of the steel beam 20 is transmitted to the column 10 through the upper and lower diaphragms 32. At this time, the shearing force generated in the panel zone is not limited by the concrete inside the panel zone but also by the square steel pipe 30. resist. Further, the shearing force of the steel frame beam 20 can be reliably transmitted as an axial force to the column 10 at the inner portion of the rectangular steel pipe 30 of the upper and lower diaphragms 32.

[0023]

[Effect of device]

 The joint structure of a reinforced concrete column and a steel beam according to the present invention uses a so-called outer diaphragm type and an inner diaphragm type together to form a taper or rib on the inner peripheral portion of the steel pipe covering the column / beam joint. Without providing it, the mechanical properties are good, the stress transmission between columns and beams can be ensured, and the required yield strength can be secured at the joint.

Further, according to the present invention, since the outer diaphragm portion is joined to the steel frame beam, a beam bracket is not required, and it is compact and has a good transportation efficiency, and the steel frame in the panel zone portion can be easily and inexpensively constructed and constructed. It is a joint structure that is extremely excellent in terms of workability at the time, and it has remarkable effects such as significant labor saving of work and shortening of construction period.

[Brief description of drawings]

FIG. 1 is a plan view showing a joint portion between a reinforced concrete column and a steel frame beam.

FIG. 2 is a vertical sectional side view taken along the line II-II in FIG.

[Explanation of symbols]

 10 Reinforced concrete columns 20 Steel beams 30 Rectangular steel pipes 32 Diaphragms 36 Four corners 40 Ribs

Claims (2)

[Scope of utility model registration request] 1. A joint structure of a reinforced concrete column and a steel beam, wherein a reinforced concrete column and a steel beam are joined together through a pair of upper and lower horizontal diaphragms, and the diaphragms are covered with a steel pipe or a steel plate, wherein the diaphragm is at least a steel beam. The portion connected to the flange of the column protrudes outward from the column outer peripheral surface, and these adjacent connecting portions protrude inward from the column outer peripheral surface at least at the intermediate portion, and the diaphragm is made of concrete. A joint structure between a reinforced concrete column and a steel beam, which is characterized in that a filling hole and a column reinforcing bar through hole are formed. 2. The joint structure according to claim 1, wherein vertical ribs are provided on both the flange connecting portions of the upper and lower diaphragms and the steel pipe or the steel plate.