JPH0635404U - Joint structure of reinforced concrete columns and steel beams - Google Patents

Abstract

(57) [Summary] [Purpose] To adopt a structure that facilitates the working of steel sheets and to secure the required rigidity and proof stress. [Structure] The bracket 20 is partially inserted into a column / beam joint at an end opposite to a connecting end with a steel beam, and is installed horizontally with the upper and lower flanges 22A and 22B of the bracket 20 and the joint. A pair of upper and lower diaphragms 30A,
It is welded by abutting with 30B. The diaphragms 30A and 30B are made of an octagonal steel plate having a circular opening 32 for concrete pouring in the center, and the web 21 of the bracket 20 is extended in the central axis direction of the reinforced concrete column 10 to form the upper and lower diaphragms. 30A, 30
It is a rib plate that vertically connects between B. The stress of the column 10 and the steel beam is transmitted smoothly and surely to each other via the bracket 20 and the upper and lower diaphragms 30A and 30B. Further, the enclosure 24 on the outer circumference of the column properly restrains the concrete in the panel zone.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a column-beam joint structure of a composite structure in which columns are reinforced concrete structures and beams are steel frames.

[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 different 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, a pair of upper and lower horizontal diaphragms and a beam bracket are provided on the outer peripheral surface of a steel pipe covering a joint between a reinforced concrete column and a steel frame 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 are provided on the inner peripheral surface of a steel pipe that covers the 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 covering the joint, so when constructing with reinforced concrete columns cast in place, there is a problem in the method of supporting the column-beam joint. 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]

 An object of the present invention is to provide a column-beam joint structure capable of ensuring required rigidity and yield strength while adopting a structure in which a steel plate can be easily worked in a joint portion between a reinforced concrete column and a steel beam. Especially.

[0007]

[Constitution of device]

 The present invention relates to a structure in which a joint between a reinforced concrete column and a steel beam is surrounded by a steel plate or a steel pipe, and a pair of upper and lower horizontal diaphragms are installed in the enclosure to join the reinforced concrete column and the steel beam to each other. Is in a non-contact state with the enclosure, and the upper and lower diaphragms and the upper and lower flanges of the steel beam are joined in the enclosure.

Further, in the joint structure according to the present invention, the outer peripheral portion of the diaphragm is not in contact with the enclosure, and the upper and lower diaphragms are joined to the upper and lower flanges of a bracket connected to the steel beam. It is characterized by that.

[0009]

[Action]

 In the joint structure of the reinforced concrete column and the steel beam, the stress of the joined column and the steel beam is smoothly and surely transmitted to each other via the bracket and the upper and lower diaphragms. Also, the enclosure on the outer periphery of the column properly 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. 1 is a plan view of a joint portion between a reinforced concrete column and a steel frame beam according to the present invention, and FIG. 2 is a vertical side view taken along line II-II of FIG. Reference numeral 10 is a reinforced concrete column, which is installed by a precast member or cast-in-place concrete. Reference numerals 12 and 14 are a column main muscle and a hoop muscle, respectively.

Reference numeral 20 is a bracket that is connected to a steel frame beam (not shown) and is made of H-shaped steel. The bracket 20 is partially inserted into the column / beam joint at the end opposite to the connection end with the steel beam, and the upper and lower flanges 22A and 22B of the bracket 20 and the upper and lower pair horizontally installed in the joint. The diaphragms 30A and 30B are butt-welded and welded.

In the present invention, the size of the diaphragms 30 A and 30 B can be smaller than the horizontal cross section of the reinforced concrete column 10. Further, the thickness of the diaphragms 30A and 30B is determined in consideration of the size of the pillar 10 and the steel beam. In this embodiment, the diaphragms 30A and 30B are made of octagonal steel plates having a circular opening 32 for concrete pouring in the center.

An enclosure 24 made of a steel plate or a steel pipe is provided on the outer peripheral surface of the joint portion of the reinforced concrete column 10. The height (length) of the enclosure 24 extends slightly above and below the positions of the upper and lower flanges 22A and 22B of the bracket 20 so as to prevent the concrete from being crushed and peeled off at the stigma and pedestal. The shape of the enclosure 24 is not limited to the rectangular shape, but is shaped into a shape corresponding to the cross section of the column 10 and plays a role of a mold.

As shown in the drawing, the bracket 20 is a rib that extends its web 21 in the direction of the central axis of the reinforced concrete column 10 to vertically connect the upper and lower diaphragms 30A and 30B, as required for strength. It may be a plate. Of course, vertical ribs may be provided separately from the bracket 20.

In this embodiment, the steel part is manufactured in advance in a factory or the like. That is, after the upper and lower diaphragms 30A and 30B and the bracket 20 are welded, the enclosure 24 which also serves as a mold is welded around the diaphragms 30A and 30B. Then, in the case of the full PC material, the pillar 10 and the steel portion are integrally cast into concrete.

After this reinforced concrete column 10 is carried into a construction site and installed at a predetermined position, the ends of the steel beam are brought in from four directions and welded or bolted to each bracket 20 to form a column / column. Beams are assembled.

On the other hand, when the pillar 10 is made of a half PC material, a steel portion in which the upper and lower diaphragms 30A and 30B and the bracket 20 are welded is placed on the pillar head of the reinforced concrete pillar 10 that has been built. Then, after joining the steel frame beam to the bracket 20, concrete is poured into the panel zone through the openings 32 of the diaphragms 30A and 30B. Since the column main bars 12 and the like are only buried in the panel zone, the concrete is filled smoothly.

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 which are joined is transmitted smoothly and surely to each other via the bracket 20 and the upper and lower diaphragms 30A and 30B.

Further, the enclosure 24 at the outer peripheral portion of the column accurately restrains the concrete in the panel zone. Further, the extended web 21 or rib plate of the bracket 20 reinforces the panel zone, and the mechanical properties of the column-beam joint are improved.

Subsequently, a joint structure of a reinforced concrete column and a steel beam without the bracket 20 will be described with reference to FIGS. 3 to 5. 3 is a horizontal sectional view of the joint portion, and FIG. 4 is a vertical cross-sectional side view taken along the line IV-IV of FIG. In these figures, the pillar main bar 12 and the hoop bar 14 are not shown, and the same members as those in the embodiment shown in FIGS. 1 and 2 are designated by the same reference numerals and their description is omitted. .

FIG. 5 shows a side view before assembling the joint portion. In the steel frame beam 40, the tips of the upper and lower flanges 42 A and 42 B project slightly from the web 41, and also the enclosure 24 is formed. Notch holes 26, 26 through which the front end portions of the upper and lower flanges 42A, 42B of the steel beam 40 are formed are formed at upper and lower side surfaces of the steel pipe.

To assemble this joint, the upper and lower flanges 42 A and 42 B of the steel beam 40 are inserted into the notch holes 26 and 26, and the inside of the steel pipe 24 is inserted as shown in FIGS. 3 and 4. Butt welding the abutting portions 31 with the upper and lower diaphragms 30A and 30B. The intersection 43 between the steel pipe 24 and the web 41 of the beam 40 and the intersection 44 between the steel pipe 24 and the upper and lower flanges 42A and 42B of the beam 40 are fillet welded.

[0023]

[Effect of device]

 Since the present invention adopts the above-mentioned structure as the joint between the reinforced concrete column and the steel beam, it not only prevents the crushing and peeling off of concrete at the column head and column pedestal but also smooths the stress of the steel beam. Moreover, it can be reliably transmitted to the reinforced concrete column, and the required rigidity and proof stress can be secured at the joint.

Further, since the diaphragm disposed at the joint portion is small and has a simple structure, it is extremely easy to process and assemble the steel portion, and in combination with the prefabricated PC member in the factory. Thus, it becomes possible to construct high-quality structures at low cost in a short period of time.

[Brief description of drawings]

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

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

FIG. 3 is a horizontal sectional view of a joint portion in another embodiment.

FIG. 4 is a vertical sectional side view taken along line IV-IV in FIG.

5 is a side view before assembling the joint shown in FIGS. 3 and 4. FIG.

[Explanation of symbols]

 10 Reinforced Concrete Column 20 Bracket 24 Enclosure (Steel Pipe) 26 Notch Hole 30A, B Diaphragm 40 Steel Beam

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Makoto Hamada 1043-1, Shimoyama, Onigakubo, Tsukuba City, Ibaraki Prefecture Kumagai Gumi Technical Research Institute Co., Ltd. Shimoyama 1043-1 Inside Kumagaya Gumi Research Laboratory (72) Inventor Hiroshi Matsuzaki 1043-1, Shimoyama Onigakubo, Tsukuba, Ibaraki Prefecture Kumagaya Gumi Research Laboratory

Claims (1)

[Scope of utility model registration request] 1. A structure in which a joint between a reinforced concrete column and a steel beam is surrounded by a steel plate or a steel pipe, and a pair of upper and lower horizontal diaphragms are installed in the enclosure to join the reinforced concrete column and the steel beam to each other. Is not in contact with the enclosure, and, in the enclosure, the upper and lower diaphragms, and the upper and lower flanges of the steel frame beam or the upper and lower flanges of a bracket connected to the beam are joined to each other. Junction structure.