JP7256698B2 - Joint structure of stepped beam - Google Patents

Description

TECHNICAL FIELD The present invention relates to a joint structure between a column and a beam, and more particularly to a joint structure for beams when there is a difference in level between the left and right beams of the column (different floor levels).

Composite structures with reinforced concrete columns and steel beams are often used in shopping centers and large-scale distribution warehouses. In order to fix the beams perpendicular to each other in the joint, a structure has been developed in which the beams having various types of joints are joined via fixing hardware as disclosed in Patent Document 1, and experiments and analyses. Based on accumulated results, the column-to-beam joints are designed to be as rigid as normal earthquake-resistant structures.

In addition, as a joint structure for coping with differences in beam height and floor level differences, for example, Patent Document 2 and Patent Document 3 disclose providing a bracket for supporting the lower part of the beam. In the joint structure disclosed in Patent Document 2, anchors corresponding to the beam height are embedded in reinforced concrete columns, and steel brackets are fixed to the anchors. By fixing the beams to the upper surface of the steel bracket, the beams can be joined via the pillars to form a structure that can be adapted even when there is a step.

In addition, in the joint structure disclosed in Patent Document 2, a square steel pipe having a surface width equivalent to the width of the beam to be joined is arranged at the center of a reinforced concrete column, and the square steel pipe is The beam ends are welded and the beam ends containing square steel pipes are embedded in concrete.

JP-A-6-240759 JP 2005-126973 A JP 2019-7245 A

According to the joint structure disclosed in the above-mentioned patent document, it is considered possible to correspond to joints of beams having various types of joints and different arrangement heights. However, in a structure in which steel beams are joined via fixing hardware as disclosed in Patent Document 1, it is difficult to join steel beams extending in the same direction with a step. In addition, the fixation hardware tends to have a complicated shape depending on the shape of the joint of the beam, or is processed to have notches, etc., so that the degree of fixation tends to be low.

In addition, in the case of the joint structure disclosed in Patent Document 2, it is necessary to embed anchors in advance in the pillars for fixing the steel brackets. Furthermore, since steel brackets are always overhanging at the ends of beams, there are cases where the locations that can be handled are limited.

Furthermore, in the case of the joint structure disclosed in Patent Document 3, the degree of fixation of the joint changes depending on the fixing method to the steel pipe, and the formwork for the column-to-beam joint becomes complicated, making on-site work complicated. Become.

In the present invention, the above problems are solved, and regardless of the size (level difference) of the step of the beam attached to the column, the structure of the joint between the column and the beam is simple, and the step can be easily constructed. The object is to provide a joint structure for beams.

A step beam joint structure according to the present invention for achieving the above object is a step beam joint structure in which two steel beams attached to the left and right of a column have different heights, and a lower beam having a low height is , a high upper beam rigidly connected to one side surface of the column is connected to the upper surface of a bracket protruding from the other side surface of the column, and an end surface of the upper beam is connected to the side surface of the column. It is characterized by not

In the stepped beam joint structure having the above characteristics, the bracket is an end portion of the lower beam penetrating the column. With such features, the lower beam and the bracket can be fixed to the pillar at once.

Further, in the joint structure of the stepped beam having the characteristics as described above, the upper beam is joined to the bracket via an adjusting member. With such characteristics, even if the height of the step is greater than the height of the lower beam or the upper beam, the joint structure according to the invention can be applied.

Further, in the joint structure of the stepped beam having the above characteristics, the height of the end of the upper beam that is joined to the bracket is configured to be smaller than the height of the other than the end of the upper beam. Characterized by With such characteristics, even if the height of the step is smaller than the height of the lower beam or the upper beam, the joining structure according to the invention can be applied.

Furthermore, the column in the joint structure of stepped beams having the characteristics described above is characterized by being made of reinforced concrete.

According to the joint structure of the stepped beam having the above characteristics, construction can be easily performed regardless of the shape of the end face and the size of the step of the beam.

FIG. 4 is a diagram for explaining the joint structure of the stepped beam according to the basic form, and is a diagram showing the configuration of the side surface in the extension direction of the beam. FIG. 2 is a diagram showing a cross section taken along line AA in FIG. 1; It is a figure which shows the 1st application form in the joining structure of a step beam. It is a figure which shows the 2nd application form in the joining structure of a step beam.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of a joint structure for stepped beams of the present invention will be described in detail with reference to the drawings. First, with reference to FIG. 1 and FIG. 2, the basic form of the joint structure of the stepped beam according to the present invention will be described. FIG. 1 is a diagram showing a beam related to joining as viewed from the side in the extension direction, and FIG. 2 is a diagram showing a cross section taken along line AA in FIG.

[Basic form]
The beams to be joined in this embodiment are two beams installed on the left and right sides of the column 10, and the height of the beam located on one side of the column and the beam located on the other side are different. be. In the example shown in FIG. 1, the height of one beam extending to the right side (one side) of the pillar 10 is the height of the other beam extending to the left side (the other side) of the pillar 10. It is joined so that it is lower than the height. Therefore, in this embodiment, one beam is called the lower beam 12 and the other beam is called the upper beam 14 . In this embodiment, the lower beam 12 and the upper beam 14 are made of steel, and the drawing shows that the lower beam 12 and the upper beam 14 are made of H-shaped steel as an example.

In this embodiment, the lower beam 12 on one side of the column 10 and the bracket 16 on the other side are at the same height. In this embodiment, the lower beam 12 is arranged so as to pass through the column 10 , and the end portion of the lower beam 12 passing through the column 10 constitutes the bracket 16 . Compared with the case where the lower beam 12 and the bracket 16 are configured separately, the number of members can be reduced, and the need to fix both the lower beam 12 and the bracket 16 to the column 10 individually is eliminated.

The upper beam 14 is configured to be joined to the upper surface of the bracket 16, and the pillar 10 and the end face (connection) of the upper beam 14 are not joined to each other so that a slight gap is provided. When the step h1 between the lower beam 12 and the upper beam 14 is larger than the height h2 of the lower beam 12 (in the example shown in FIG. 1, the height h2 of the lower beam 12 and the height h2 of the upper beam 14 are height h4 is the same), and a gap h3 is created between them. Therefore, when the gap h3 occurs, the lower beam 12 and the upper beam 14 are joined via the adjusting member 18 . Here, the structure of the adjusting member 18 is not limited.

As a method for joining the lower beam 12 (bracket 16), the upper beam 14, and the adjustment member 18, a known joining method such as welding or bolting may be adopted.

[effect]
According to the joint structure of the stepped beam as described above, it is possible to cope with a large step by changing the height of the adjusting member 18 . In addition, since it is a simple structure in which the upper beam 14 is joined to the upper surface of the lower beam 12 through which the column 10 is passed, the necessity of processing the steel beam is low and the construction is easy. Further, by rigidly joining the lower beam 12 to the column 10, it is possible to cope with a long span and a large load.

In addition, when constructing the column 10, there is no need to construct a formwork having a complicated shape, and workability at the site can be maintained satisfactorily. Furthermore, it can be applied regardless of the end face shape of the beams (lower beam 12, upper beam 14). Moreover, since the workability is good, it can be constructed at a low cost.

Also, the upper beam 14 is not joined to the pillar 10 at the end located on the pillar 10 side. The upper beam 14 is joined to the upper surface of the bracket 16 formed by the end portion of the lower beam 12 (in the example shown in FIGS. 1 and 2, it is joined through the adjustment member 18). Therefore, construction is easier than when the upper beam 14 is joined to the side surface of the pillar 10 or fixed inside.

[First Application Mode]
In the basic configuration described above, when the step h1 between the lower beam 12 and the upper beam 14 is larger than the height h2 of the lower beam 12, the adjusting member is positioned between the upper surface of the lower beam 12 and the lower surface of the upper beam 14. It is described that the bonding is performed after 18 is arranged. However, when the step h1 between the lower beam 12 and the upper beam 14 is equal to the height h2 of the lower beam 12, the upper beam 14 is joined directly to the upper surface of the lower beam 12 as shown in FIG. It may be configured.

If the level difference is such that a gap does not occur between the lower beam 12 and the upper beam 14, the two can be directly joined, and the members required for joining can be reduced. Moreover, even in the case of such a joint structure, as in the basic form described above, since the structure is such that the joint is simple, the workability of the steel frame beam is low, and construction can be easily performed.

In addition, when constructing the columns, there is no need to construct a formwork with a complicated shape, and good workability can be maintained at the site. Furthermore, it can be applied regardless of the shape of the end surface of the beam. Moreover, since the workability is good, it can be constructed at a low cost.

[Second application mode]
In the basic mode and the first application mode described above, the relationship between the step h1 between the lower beam 12 and the upper beam 14 and the height h2 of the lower beam 12 is h1>h2 or h1=h2. I described a case.

Here, when the step h1 between the lower beam 12 and the upper beam 14 is smaller than the height h2 due to the lower beam 12 (h1<h2), as shown in FIG. By making the vertical height h5 smaller than the vertical height h4 of the other portion of the upper beam 14, the step can be adjusted.

By adopting such a structure, it is possible to cope with the case where the level difference h1 is small while maintaining the strength of the beam.

In the embodiment shown in FIG. 4, the lower flange of the upper beam 14 is brought closer to the upper flange so that the height h5 of the end portion is smaller than h4, and the step h1 is the height of the lower beam 12. It is intended to deal with the case where it is smaller than h2. However, in the joint structure of the stepped beam according to the present invention, the upper flange of the lower beam 12 is brought closer to the lower flange, and adjustment is performed to reduce the force of the bracket 16, thereby coping with the step h1. You can do it.

Reference numerals 10: pillar, 12: lower beam, 14: upper beam, 16: bracket, 18: adjustment member.

Claims (4)

A stepped beam joint structure in which two steel beams attached to the left and right of a column have different heights,
A lower beam having a low height penetrates the column and is rigidly connected to one side surface of the column ,
The upper beam having a high height is joined to the upper surface of the end of the lower beam that protrudes from the other side surface of the pillar and constitutes a bracket ,
The joint structure of the stepped beam, wherein the end face of the upper beam is not joined to the side surface of the column. The joining structure of the stepped beam according to claim 1 , wherein the upper beam is joined to the bracket via an adjusting member. 2. The joining structure of the stepped beam according to claim 1 , wherein the height of the end of the upper beam that is joined to the bracket is smaller than the height of the other than the end of the upper beam. The joint structure of the stepped beam according to any one of claims 1 to 3 , wherein the pillar is made of reinforced concrete.

Images