JPH08189092A - How to join steel columns with different cross-sectional shapes - Google Patents

Abstract

(57) [Summary] [Purpose] To provide an efficient joining method when joining an upper-floor steel column having a smaller cross section to a lower-floor steel column, which is a rectangular steel column. [Structure] A square steel pipe with the same cross section as the lower floor square steel column is welded to the lower end steel plate, reinforcing bars are arranged inside, and an upper end steel plate with a stud bolt with a head is attached to the upper end. Welded the lower floor rectangular steel column to the lower surface of the cube type joint that was welded
The upper floor steel column having a cross section smaller than that of the lower floor square steel column is welded to the upper surface thereof, and mortar is filled inside the cubic shaped fitting.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joining method for joining an upper portion of a rectangular steel column of a steel frame body to a steel column having a smaller cross section than that.

[0002]

2. Description of the Related Art With the increase in the height of steel-framed structures, there are increasing opportunities to join square-shaped, H-shaped, and T-shaped steel-framed columns having a smaller cross section than the square-shaped steel-framed columns. As the joining method in this case, since the upper and lower column cross sections do not match, as shown in FIG.
It is common to use special fittings such as thickened top-end joint steel plate, (b) top-end joint steel plate welded with rib steel plate, and (c) taper square steel pipe Is.

[0003]

In the conventional method (a), although the strength and rigidity of the steel plate having a top end is increased, it is necessary to use a considerably thick steel plate, and the use efficiency is deteriorated. In the method (b), it is necessary to weld the rib steel plate also to the upper end steel plate, and not only the workability is poor but also the deformation occurs at the time of welding.

In the method (c), not only the time and labor required to process the tapered rectangular steel pipe increase, but also the required machining accuracy (the upper end cross section corresponds to the upper story column cross section, and the lower end cross section corresponds to the lower story column cross section). It is not easy to satisfy the accuracy of tapering continuously. There are problems such as.

[0005]

The present invention provides a conventional method (b).
While following the above idea, a stud bolt with a head is installed on the lower surface of the steel plate at the top of the joint of the joint and the mortar is filled inside the joint of the joint to solve the problems of the conventional method.

That is, according to the present invention, a lower end steel plate is welded to the lower end of a rectangular steel pipe having the same cross-section as the lower floor rectangular steel column, reinforcing bars are arranged inside, and a stud with a head is provided at the upper end. Cube-shaped joint with welded upper-end steel plate with bolts Weld a lower-floor rectangular steel column to the lower surface of the object, weld an upper-floor steel column having a smaller cross section than the lower-floor rectangular steel column to the upper surface, and A method for joining steel columns having different cross-sectional shapes, which is characterized by filling mortar inside the mold part.

The point of the present invention is that
The point is to fill the mortar inside the fitting with the headed stud bolts attached to extend the upper steel columns to be welded later.

By adopting the joining method of the present invention, it is possible to increase the thickness of the steel plate at the upper end, manufacture a square steel pipe with a taper, and weld rib steel plates without taking special measures. It is possible to sufficiently transmit the column stress to the lower floor column and to form a joint portion having sufficient strength and rigidity.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings showing the embodiments of the present invention.

1A to 1D show steps for completing an example of a joint portion according to the present invention. FIGS. 1A to 1D are longitudinal sectional views, and FIG. Is. The present invention will be described while explaining an example of manufacturing a metal fitting used for the joint part of the present invention. In this example, a square steel column having a smaller cross section than that of the lower square steel column was used as the upper steel column.

(1) A rectangular steel pipe 2 having the same cross section as the lower floor rectangular steel column is cut into a predetermined length. (FIG. 1 (a)) (2) The lower end steel plate 4 is welded to the lower end of the rectangular steel pipe 2, and the reinforcing bar 5 is installed inside the rectangular steel pipe 2. On the other hand, a plurality of (7 in this example) headed stud bolts 3 are provided at predetermined positions on the upper end steel plate 6 having the mortar injection holes 7 (positions at which the lower ends of the upper-order square-shaped steel columns 9A to be welded later ride). Are arranged in an L shape and welded. (Fig. 1 (b), Fig. 1 (e)) When the cross-sectional shape of the upper steel column is H-shaped, it is arranged in a T-shape and welded, and when the cross-sectional shape is T-shaped, it is I-shaped. Placed in a mold and welded.

(3) The upper end steel plate 6 to which the headed stud bolt 3 is welded is welded to the upper end of the square steel pipe 2. (Figure 1
(C)) (4) The steel plate of the upper floor square type steel frame column 9A is located on the steel plate of the lower floor square type steel frame column 9B, and the other two side plates are located on the headed stud bolt 3. The upper end steel plate 6 is welded to the upper surface as described above. Lower floor rectangular steel column 9B to lower end steel plate 4
And weld the H-shaped steel beam 10 to the side surface of the fitting 1 such that the upper flange 10A is at the side surface position of the upper end steel plate 6 and the lower flange 10B is at the side surface position of the lower end steel plate 4. To do.

Thereafter, the non-shrink mortar 8 is injected into the rectangular steel pipe 2. Welding of columns and beams and non-shrink mortar 8
The order of injection may be reversed.

In this process, the upper-level square steel frame pillar 9A is usually used.
The welding of the lower floor rectangular steel column 9B to the joint fitting and the welding of the H-shaped steel beam 10 as the end beam are performed at the factory together with the injection of the non-shrink mortar 8 into the inside of the joint fitting 1. A bolt hole (not shown) is drilled at the end of the end beam of the H-shaped steel beam 10 and is joined to the intermediate beam of the H-shaped steel beam 10 with a high-strength bolt on site. However, depending on the circumstances, the process up to the step of injecting the non-shrink mortar 8 may be carried out in the factory to manufacture the joint fitting 1, and may be directly welded to the pillar or beam on site.
A method of directly welding a beam on-site by using the fitting 1 which has been subjected to the steps of welding the pillar and injecting the non-shrink mortar 8 in the factory may be adopted.

FIG. 2 shows a typical example of a conventional joint fitting,
Let me give you some supplementary explanation.

(A) is an example in which a thick steel plate is used as the upper end steel plate 6 of the fitting 1, (b) is an example in which a rib steel plate 11 is welded to the lower surface of the upper end steel plate 6 of the fitting 1, (C) is an example in which a tapered pipe 12 whose cross-sectional area is gradually changed is used as the rectangular steel pipe of the fitting 1.

[0017]

According to the present invention, a steel stud having a different upper and lower cross-sectional shape is attached to a fitting having a stud bolt with a head attached to the lower surface of a steel plate having a top end to extend an upper steel column to be welded later. To form a joint with sufficient strength and rigidity that can transmit the stress of the upper column to the lower column with a simple operation of welding and filling the mortar inside the joint. You can Therefore, the workability is improved and the construction cost is reduced.

[Brief description of drawings]

FIG. 1 shows a process until one example of a joint portion is completed according to the present invention, (a) to (d) are longitudinal sectional views, and (e) is a view as seen from an arrow A in (d). .

FIG. 2 is a vertical cross-sectional view showing a typical example of a conventional joint section.

[Explanation of symbols]

1 ・ ・ Metal fittings 2 ・ ・ Square steel pipes 3 ・ ・ Stud bolts with heads 4 ・ ・ Lower-end joint steel plates 5 ・ ・ Reinforcing bars 6 ・ ・
Top end steel plate, 7 ・ ・ Mortar injection hole, 8 ・ ・ No shrinkage mortar, 9A ・ ・ Upper column, 9B ・ ・ Lower column, 10 ・ ・ Steel beam, 10A ・ ・ Steel beam upper flange, 10B ・ ・Steel frame lower flange, 11 ... rib steel plate, 12 ... tapered pipe.

Claims (1)

[Claims] 1. A lower-end square steel pipe having the same cross section as that of a lower-order square steel column is welded to the lower end with a steel plate with a lower end, reinforcing bars are arranged inside, and an upper end with a headed stud bolt is attached to the upper end. The lower-sided rectangular steel-framed column is welded to the lower surface of the cube-shaped jointed product that is welded to the steel plate, and the upper-staged steel-framed column having a smaller cross-section than the lower-ordered rectangular steel-framed column is welded to the upper surface, and the cubical-typed fixture is also welded. A method of joining steel columns having different cross-sectional shapes, characterized by filling mortar inside.