JP2025018243A - Beam-column joint structure - Google Patents

Abstract

To provide a column-beam connection structure suitable for a column-beam connection structure between a steel beam and a reinforced concrete column.SOLUTION: A column-beam connection structure 1 is a column-beam connection structure for connecting a composite structure beam 30 consisting of a central part steel beam of a material end reinforced concrete beam 33, a steel beam 20 disposed in a direction intersecting with the steel beam, and a reinforced concrete column. The column-beam connection structure comprises: a reinforced concrete column member having a steel beam end 21 of the steel beam 20 supported on the reinforced concrete column among the steel beams 20 and a beam intersection 40 that covers the steel beam end 21 and is connected with the composite structure beam 30; and a composite structure beam end precast concrete member 31 constituting an end of the composite structure beam 30 at which one end in a long axis direction of a steel beam end 32 is disposed so as to be spaced a predetermined distance D1 away from the steel beam end 21 through the beam intersection 40.SELECTED DRAWING: Figure 1

Description

The present invention relates to a beam-column joint structure, and in particular to a composite structural beam consisting of a reinforced concrete beam at the end and a steel beam in the middle, and to a beam-column joint structure between a steel beam and a reinforced concrete column.

In order to ensure a large beam span for buildings and to shorten construction time, a composite structure may be used that combines H-shaped steel beams with good cross-sectional performance and reinforced concrete columns that are resistant to compressive forces.

Furthermore, to reduce on-site construction work, the ends of composite structural beams may be made of precast concrete, as shown in Patent Document 1, for example.

Japanese Patent Application Publication No. 3-066852

In the column-beam joint structure described in Patent Document 1, the intersections of steel beams 3, 3 are rigidly joined by welding or the like at a steel frame factory to create a rigid frame structure in both the X and Y directions. However, this column-beam joint structure requires a lot of effort in welding because the cross-sectional shape near where the steel beams intersect is complex, and the work requires the services of experienced welders, resulting in significant costs and time. In addition, because the beams are composite structures in both the X and Y directions, the overall dimensions of the precast members are large, making it difficult to load them onto the beds of transport trucks, which have width limitations.

The object of the present invention is to provide a column-beam joint structure suitable for a column-beam joint structure between a steel beam and a reinforced concrete column.

In order to achieve the above object, the present invention provides a column-beam joint structure between a first composite structural beam consisting of a first steel beam at the center of a reinforced concrete beam at the end of the member, a second steel beam erected in a direction intersecting the first steel beam, and a reinforced concrete column, the column-beam joint structure being characterized in that it comprises a reinforced concrete column member having a steel beam end of the second steel beam supported on the top of the reinforced concrete column, a beam intersection portion covering the steel beam end of the second steel beam and to which the first composite structural beam is joined, and a first composite structural beam end precast concrete member constituting the end of the first composite structural beam, in which one end of the steel beam end of the first steel beam in the longitudinal direction is positioned at a predetermined interval from the steel beam end of the second steel beam via the beam intersection portion.

It is preferable that the reinforced concrete column member further has a second composite structural beam end portion constituting the end portion of a second composite structural beam, in which one end portion in the longitudinal direction of the steel beam end portion of a third steel beam that faces the first steel beam across the beam intersection portion is positioned at a predetermined distance from the steel beam end portion of the second steel beam via the beam intersection portion.

It is preferable that the other first steel beam further includes another composite structural beam end, the longitudinal end of which faces the first composite structural beam across the beam intersection and is positioned at the predetermined distance from the steel beam end of the second steel beam.

It is preferable that the steel beam end of the second steel beam is covered with reinforced concrete, and that the reinforced concrete is formed integrally with the beam intersection.

The beam intersection is preferably formed with an insertion hole for inserting the column main reinforcement of the reinforced concrete column or a mechanical joint for connecting the column main reinforcement, and the column main reinforcement is inserted into the insertion hole or connected to the mechanical joint, and the beam intersection is preferably placed on the body of the reinforced concrete column to integrate the beam intersection with the reinforced concrete column.

It is preferable that the floor slab supported by the first composite structural beam and the second steel beam has a structural slit along the boundary between the end and center of the first composite structural beam.

The present invention provides a column-beam joint structure suitable for a column-beam joint structure between a steel beam and a reinforced concrete column.

FIG. 1A is a front cross-sectional view showing a column-beam joint structure between a steel beam and a composite structural beam and a reinforced concrete column according to the first embodiment of the present invention, and FIG. 1B is a plan cross-sectional view taken along the Ib-Ib cross-sectional line in FIG. 1A is a front cross-sectional view of a composite structural beam end precast concrete member and a precast reinforced concrete column member in the first embodiment, and FIG. 1B is a plan cross-sectional view taken along the IIb-IIb section line in FIG. 1A. FIG. 1 is a plan view showing a column-beam structure including a column-beam joint structure between a steel beam and a composite structural beam and a reinforced concrete column in the first embodiment. (a) is a plan cross-sectional view of a composite structural beam end precast concrete member and a precast reinforced concrete column member used in a column beam joint where a steel beam is spanned in only one direction; (b) is a plan cross-sectional view of a composite structural beam end precast concrete member and a precast reinforced concrete column member used in a column beam joint where a composite structural beam is spanned in only one direction; and (c) is a plan cross-sectional view of a composite structural beam end precast concrete member and a precast reinforced concrete column member used in a column beam joint where a steel beam and a composite structural beam are spanned in only one direction, respectively. FIG. 2 is a plan view showing a column-beam joint structure between a steel beam and a composite structural beam and a reinforced concrete column, and a floor slab, in the first embodiment. FIG. 6A is a front cross-sectional view showing the column-beam joint structure between a steel beam and a composite structural beam and a reinforced concrete column according to the second embodiment of the present invention, and FIG. 6B is a plan cross-sectional view taken along the VIb-VIb cross-sectional line in FIG. 6A. 7A is a front cross-sectional view of a composite structural beam end precast concrete member and a precast reinforced concrete column member in the second embodiment, and FIG. 7B is a plan cross-sectional view taken along the VIIb-VIIb cross-sectional line in FIG. 7A. 8A is a front cross-sectional view showing a column-beam joint structure between a steel beam and a composite structural beam and a reinforced concrete column according to a modified example, and FIG. 8B is a plan cross-sectional view taken along the VIIIb-VIIIb cross-sectional line in FIG. 8A. FIG. 1A is a plan view showing a column-beam structure including a column-beam joint structure between a steel beam and a composite structural beam and a reinforced concrete column according to another modified example, and FIG. 1B is a plan view showing a column-beam structure including a column-beam joint structure according to yet another modified example.

The composite structural beam end precast concrete member and precast reinforced concrete column member and beam-column joint structure according to an embodiment of the present invention will be described below with reference to the attached drawings. Note that identical or equivalent components are given the same reference numerals.

[First embodiment]
1(a) and (b) show a column-beam joint structure 1 according to a first embodiment of the present invention. The column-beam joint structure 1 is composed of a precast reinforced concrete column member 10, a steel beam 20 penetrating the precast reinforced concrete column member 10, and a composite structural beam 30 erected in a direction intersecting the steel beam 20. The column-beam joint structure 1 uses the precast reinforced concrete column member 10 shown in Figs. 2(a) and (b) and a composite structural beam end precast concrete member 31 connected to a beam intersection portion 40 (described later) of the precast reinforced concrete column member 10.

The precast reinforced concrete column member 10 (hereinafter referred to as column 10) is a column made of reinforced concrete with a cross section of 1050 mm x 1050 mm, which is manufactured in advance at a specified factory. As shown in Figures 1(a), (b) and 2(a), (b), a beam intersection 40 is provided at the top of the column body 11 to which a steel beam 20 and a composite structural beam 30 are connected. Composite structural beam ends 31 are connected to two parallel faces of the beam intersection 40, which has the same planar dimensions as the column cross section of the column 10, and steel beam ends 21 extend from the other two parallel faces, and the composite structural beam ends 31 and the steel beam ends 21 are connected via the beam intersection 40. In the beam intersection 40, the tie bars 13 are arranged by penetrating the webs 23 of the steel beam ends 21 at the height where the steel beam ends 21 are arranged. The column main reinforcement 12 protruding from the upper end of the beam intersection 40 is arranged in a position that does not interfere with the steel beam end 21 of the steel beam 20. In addition, the beam intersection 40 is provided with upper end reinforcement 16 and lower end reinforcement 17 that are connected to the upper end reinforcement 34 and lower end reinforcement 35 of the composite structural beam end 31.

1(a) and (b), the steel beam 20 is an H-shaped steel, and is installed so as to penetrate the column body 11 of the column 10. In this embodiment, the steel beam 20 has a beam depth and beam width of 900 mm x 300 mm. The steel beam 20 is composed of a steel beam end 21 that constitutes part of the column 10, and a steel beam center 22 that is connected to the steel beam end 21. The steel beam 20 has a longer-term allowable strength than the composite structural beam 30. For this reason, as shown in FIG. 3, a small beam 50 is arranged at a predetermined interval between the steel beams 20, 20. Note that in FIG. 3, the beam spans of the steel beam 20 and the composite structural beam 30 are shown to be the same, but in this embodiment, the beam span of the steel beam 20 is 10.5 m, and the beam span of the composite structural beam 30 is 9.5 m.

As shown in Figures 1(a), (b) and 3, the composite structural beam 30 consists of a composite structural beam end precast concrete member 31 (hereinafter referred to as the composite structural beam end 31) and a steel beam central portion 39 connected to the composite structural beam end 31.

The composite beam end 31 constituting the end of the composite beam 30 is composed of the steel beam end 32 of the H-shaped steel arranged in a direction intersecting with the steel beam 20, and the reinforced concrete beam 33 formed by surrounding the beam intersection 40 side of the steel beam end 32 with the upper end reinforcement 34, the lower end reinforcement 35 and the stirrup reinforcement 36 and pouring concrete to ensure a sufficient cover thickness. The beam intersection 40 side of the steel beam end 32 does not contact the column 10 in a plan view, and is joined to the steel beam 20 and the column 10 via the reinforced concrete beam 33 and the beam intersection 40. In this embodiment, the beam intersection 40 side of the steel beam end 32 is arranged with a distance D1 of about 500 mm from the steel beam 20 and a distance D2 of about 200 mm from the column 10. The steel beam end 32 and the steel beam center 39 have a beam depth and beam width of 800 mm x 300 mm. The reinforced concrete beam 33 has a beam depth and width of 1200 mm x 600 mm, and a beam length of 2000 mm. The upper end reinforcement 34 and the lower end reinforcement 35 are arranged in the reinforced concrete beam 33. An anchoring metal fitting 38 is attached to the end 37 of one end (at the center of the composite structural beam) of the upper end reinforcement 34 and the lower end reinforcement 35, and a known mechanical joint 70 is provided at the other end (at the end of the composite structural beam) to connect to the upper end reinforcement 16 and the lower end reinforcement 17 of the beam penetrating the column 10. Stirrup reinforcements 36 are arranged to surround the upper end reinforcement 34 and the lower end reinforcement 35 at a predetermined interval, and at the end 37, the stirrup reinforcements 36 are arranged at close intervals to reinforce the reinforced concrete beam 33 near the end 37. In addition, it is preferable that the length of the reinforced concrete beam 33 is 1.5 to 3 times the length of the steel beam whose longitudinal ends are covered with reinforced concrete.

(Configuration of column-beam joint structure 1-4)
1(a) and 1(b), in the beam-column joint structure 1, the longitudinal ends of composite structural beams 30, 30 are connected to the beam width direction end of a steel beam 20 via a beam intersection 40 placed on a column body 11 of a column 10. Upper end reinforcements 34 and lower end reinforcements 35 are arranged at predetermined intervals from the inside of the reinforced concrete beam 33 at the longitudinal end of one composite structural beam 30 through the upper end reinforcements 16 and lower end reinforcements 17 that penetrate the beam intersection 40 at the top of the column body 11 to the inside of the reinforced concrete beam 33 at the longitudinal end of the other composite structural beam 30.

The composite beam end precast concrete member 31 and the precast reinforced concrete column member 10 are used in the column beam joint structure 1 of the interior column in which the steel beam end 21 and the composite beam end 31 extend in two directions. The composite beam end precast concrete member 31 and the precast reinforced concrete column member 10A shown in Figure 4 (a) are used in the column beam joint structure 2 of the outer periphery column in which the steel beam end 21 extends in only one direction (the steel beam end does not extend from end face A) (Figure 3). The composite beam end precast concrete member 31 and the precast reinforced concrete column member 10B shown in Figure 4 (b) are used in the column beam joint structure 3 of the outer periphery column in which the composite beam end 31 extends in only one direction (the composite beam end does not extend from end face B). The composite structural beam end precast concrete member 31 and precast reinforced concrete column member 10C shown in FIG. 4(c) are used in the column-beam joint structure 4 of a corner column in which the steel beam end 21 and the composite structural beam end 31 each extend in only one direction (the steel beam end does not extend from end face A, and the composite structural beam end does not extend from end face B).

As shown in FIG. 5, the floor slab 60 supported by the composite structural beam 30 and the steel beam 20 has a structural slit 61 along the boundary between the composite structural beam end 31 and the central part 39 of the steel beam. The length L of the structural slit 61 is equivalent to the effective width of the floor slab 60 relative to the central part 39 of the steel beam.

According to the column-beam joint structure 1 of this embodiment, the steel beam central part 22 is bolted to the beam intersection part 40 of the column 10, and the upper end reinforcement 16 and the lower end reinforcement 17 of the beam intersection part 40 are inserted into the mechanical joint 70 of the composite structural beam end part 31, and then grout is injected, and the steel beam central part 39 is bolted to the steel beam end part 32, so that a rigid frame structure can be easily constructed. In addition, by using precast concrete members, large-scale temporary members, reinforcement work, formwork work, concrete pouring work, etc. are not required, and construction time and costs can be reduced. In the column-beam joint structure 1, since there is no steel beam at the end in the longitudinal direction of the composite structural beam 30 where the bending moment is large, the design moment of the central steel part is reduced, and the cross section of the steel beam end part 32 and the steel beam central part 39 can be reduced, thereby reducing costs. Furthermore, the construction method can be used to reduce the size of heavy machinery and significantly shorten the construction period. In addition, both the column 10 and the composite beam end 31 are straight members, and therefore even if they are precast, they can be easily transported to the site, improving transportation efficiency. Since welding is not required between the mutually perpendicular steel beam 20 (steel beam end 21) and the steel beam end 32, it is possible to process steel materials without fabricating S grade or H grade steel, which requires advanced technology, and costs can be reduced. In addition, by providing the yield hinge at the steel beam end 32, the Ds value (structural characteristic coefficient) can be reduced, enabling rational structural design. By moving the yield hinge to the steel beam end 32, a plastic hinge is not formed at the end of the composite beam, so that an A-class joint can be provided for the mechanical joint 70 at the composite beam end 31. Furthermore, since the steel beam end 32 is not embedded in the column 10 in plan view, when arranging the column main reinforcement 12, it is only necessary to arrange it around the steel beam end 21 without considering the arrangement of the steel beam end 32. This increases the degree of freedom in arranging the column main reinforcement 12 compared to a structure in which steel beams in both directions are joined on the column, allowing for a reduction in the column cross section, improved workability, and shortened construction time. In addition, since the structural slit 61 is provided in the floor slab 60, it is possible to suppress an increase in the bending strength of the hinge part between the steel beam end 32 and the steel beam central part 39, and to alleviate the stress generated in the reinforced concrete near the joint part. This makes it possible to reduce the upper end reinforcement 34, lower end reinforcement 35, and stirrup reinforcement 36 of the reinforced concrete beam 33. In this way, the column beam joint structure 1 is a column beam joint structure suitable for a column beam joint structure between a steel beam and a reinforced concrete column.

[Second embodiment]
6(a) and (b) show a beam-column joint structure 5 according to a second embodiment of the present invention. This embodiment differs from the first embodiment in that the column 10D constituting the beam-column joint structure 5 is a precast member that is manufactured in a factory by integrating a precast reinforced concrete column 10 and one composite structural beam end 31.

(Configuration of column-beam joint structure 5)
As shown in Figures 6(a), 6(b), 7(a), and 7(b), in the column 10D, upper end reinforcement 16 and lower end reinforcement 17 are arranged from the composite beam end 31A to the beam intersection 40, and are connected to the upper end reinforcement 34 and lower end reinforcement 35 of the composite beam end 31 via mechanical joints 70, respectively. Therefore, the column-beam joint structure 5 in which the composite beam 30 and the steel beam 20 cross is constructed by connecting one composite beam end 31 and two steel beam central parts 39 to the column 10D. The composite beam end 31A has the same configuration as the composite beam end 31, except that it does not have a mechanical joint 70.

According to the column-beam joint structure 5 of this embodiment, the column 10D is equipped with a composite beam end 31A, so the transportation and joining work of the composite beam end 31 can be reduced by one. This shortens the construction period and reduces the number of transportations, resulting in cost reduction. In addition, costs can be reduced by reducing the number of mechanical joints 70 to less than half. Therefore, the column-beam joint structure 5 can provide an ideal column-beam joint structure.

[Modification]
In the first and second embodiments, the upper end reinforcement 16 and the lower end reinforcement 17 protrude from the beam intersection 40 of the column 10, and the mechanical joint 70 connecting them is provided to the composite structure beam end precast concrete member 31, but as shown in Figures 8 (a) and (b), the upper end reinforcement 34 and the lower end reinforcement 35 may protrude from the composite structure beam end precast concrete member 31B, and the mechanical joint 70 connecting them may be provided to the beam intersection 40 of the column 10V. Alternatively, a column in which the upper end reinforcement 16 and the lower end reinforcement 17 protrude from one side of the beam intersection 40 and the mechanical joint 70 is provided on the other side of the beam intersection 40, a composite structure beam end provided with the mechanical joint 70 connected to one side of the beam intersection 40, and a composite structure beam end in which the upper end reinforcement 34 and the lower end reinforcement 35 protrude and are connected to the mechanical joint 70 on the other side of the beam intersection 40 may form a column beam joint structure. Alternatively, at least one of the members may be a half-precast member, and the reinforcing bars may be joined to each other using lap joints, gas pressure welding joints, welded joints, etc.

In the first and second embodiments, the steel beam end 21 is covered with reinforced concrete at the beam intersection 40, but as shown in FIG. 9(a), the steel beam end 21 may be covered with a precast reinforced concrete beam 24, like the steel beam end 32. Alternatively, the beam intersecting the composite structural beam 30 may not be a steel beam, but may be a reinforced concrete beam 80 (constituting reinforced concrete 81), as shown in FIG. 9(b).

In the first and second embodiments, one end of the steel beam end 32 is spaced a distance D1 from the column 10, but the distance D2 between the steel beam end 32 and the column 10 may be set to 0, so that the steel beam end 32 is in contact with the column 10 in a plan view.

In addition, in the first and second embodiments, the pillar 10 is a precast reinforced concrete pillar, but it may be a reinforced concrete pillar such as a half-precast concrete pillar. Alternatively, in the first embodiment, it may be a cast-in-place reinforced concrete pillar.

In the first and second embodiments, the composite structural beam end 31, 31 and the steel beam end 21, 21 were connected via one steel beam central portion 39, 22, respectively, but they may be connected via two or more steel beam central portions, respectively.

In addition, in each of the above embodiments, the composite structural beam ends 31, 31A, and 31B were precast concrete members, but they may be half precast members when it is necessary to reduce the weight of the members.

In the first embodiment, the column body 11 and the beam intersection 40 are integrated into the precast reinforced concrete column member 10, but the column body 11 and the beam intersection 40 may be separated, with only the column body 11 being made of cast-in-place reinforced concrete or precast concrete, and the beam intersection 40 being made of precast concrete. In this case, it is preferable to incorporate a sheath tube or reinforcing bar joint into the beam intersection 40 for inserting the column main reinforcement.

In the second embodiment, the column 11, the beam intersection 40, and one of the composite structural beam ends 31A are integrated into a precast reinforced concrete member 10D. However, it is also possible to integrate only the beam intersection 40 and the composite structural beam end 31A, divide the column 11, and use cast-in-place reinforced concrete or precast concrete for the column 11 alone, and use precast concrete for the integrated beam intersection 40 and composite structural beam end 31A. In this case, it is preferable to incorporate a sheath tube (insertion hole) or a reinforcing bar joint into the beam intersection 40 for inserting the column main reinforcement.

The present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the claims. In other words, embodiments obtained by combining technical means that are appropriately modified within the scope of the claims are also included in the technical scope of the present invention.

1, 2, 3, 4, 5 Beam-column joint structure 10, 10A, 10B, 10C, 10D, 10H, 10I, 10J, 10K, 10O, 10P, 10Q, 10R, 10V Precast reinforced concrete column member (column)
11 Column body 12 Column main reinforcement 13 Hoop reinforcement 16, 34 Upper end reinforcement 17, 35 Lower end reinforcement 20 Steel beam 21, 32 Steel beam end 22, 39 Steel beam center 30 Composite structural beam 31, 31A, 31B Composite structural beam end precast concrete member (composite structural beam end)
24, 33, 80 Reinforced concrete beam 36 Stirrup bar 40 Beam intersection 50 Sub-beam 60 Floor slab 61 Structural slit 70 Mechanical joint D1, D2 Spacing

Claims (6)

A column-beam joint structure between a first composite structural beam consisting of a first steel beam at the center of a reinforced concrete beam at the end of the material, a second steel beam erected in a direction intersecting the first steel beam, and a reinforced concrete column,
Among the second steel beams, a reinforced concrete column member having a steel beam end of the second steel beam supported on an upper portion of the reinforced concrete column and a beam intersection portion covering the steel beam end of the second steel beam and to which the first composite structural beam is joined;
A first composite structural beam end precast concrete member constituting an end of the first composite structural beam, in which one end of the steel beam end of the first steel beam in the longitudinal direction is arranged at a predetermined interval from the steel beam end of the second steel beam via the beam intersection portion;
Equipped with
A column-beam joint structure characterized by the above. The reinforced concrete column member further has a second composite structural beam end portion constituting an end portion of a second composite structural beam, in which one end portion of a steel beam end portion of a third steel beam facing the first steel beam across the beam intersection portion is arranged at a predetermined interval from the steel beam end portion of the second steel beam through the beam intersection portion.
The column-beam joint structure according to claim 1 . Further, one end of the steel beam end of the other first steel beam in the longitudinal direction faces the first composite structural beam across the beam intersection and is arranged at a predetermined interval from the steel beam end of the second steel beam.
The column-beam joint structure according to claim 1 . The steel beam end of the second steel beam is covered with reinforced concrete, and the reinforced concrete is integrally formed with the beam intersection.
The column-beam joint structure according to claim 1 . At the beam intersection, an insertion hole for inserting the column main reinforcement of the reinforced concrete column or a mechanical joint for connecting the column main reinforcement is formed,
The column main reinforcement is inserted into the insertion hole or the column main reinforcement is connected to the mechanical joint, and the beam intersection is placed on the column body of the reinforced concrete column to integrate the beam intersection with the reinforced concrete column.
The column-beam joint structure according to claim 1 . A floor slab supported by the first composite structural beam and the second steel beam has a structural slit along the boundary between the end and center of the first composite structural beam.
The column-beam joint structure according to claim 1 .