JPH1161994A - Column-beam joint of steel frame and connection method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent early breakage of a steel frame beam, by gradually reducing the sectional arera of the steel frame beam from the end to the central part of the span, in a steel frame column-beam joint formed by connecting the steel frame column and the steel beam. SOLUTION: A wide flange shaped-beam 1 is used for a steel frame beam and a reinforcing plate 11 is integrally connected along the upper face of the upper flange 1a and reinforcing plates 21, 21 are integrally connected along the upper face of the lower flange 1a. The sectional area of the reinforceing plates 11, 21 are gradually reduced from the beam end to the central part of the span. The sectional change narrowing the width is maximized in the range H from the end to the position X where the stress caused by an external force gets to the maximum value and the sectional change is moderated in the range H' to the central part of the span in the front side thereof. And a steel pipe column 2 provided with a diaphragm 3 at the position of the beam flange 1a, is used as the steel frame column. And hence, early breakage of the steel frame column can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel beam-column joint and a beam-to-column connection between a steel column such as a steel pipe column or an H-shaped steel column and a steel beam such as an H-shaped steel beam or an assembled beam. Belongs to the technical field of joining method.

[0002]

2. Description of the Related Art Various types of steel beam-to-column joints and beam-to-column joining methods are known in which steel columns such as steel pipe columns or H-shaped columns are joined to steel beams such as H-shaped beams or assembled beams. is there. For example, as shown in FIGS. 12A to 12C, a flange a ′ of an H-shaped steel beam a is used.
Is welded into the diaphragm c of the steel pipe column b by welding, and the beam web a ″ is fillet welded to the contact surface b ′ of the steel pipe column b to form a beam-to-column joint, as shown in FIGS. 13A to 13C. As described above, the flange a 'of the H-shaped steel beam a is melted and welded to the diaphragm c of the steel tube column b, and the beam web a "is connected to the contact surface b' of the steel tube column b with the high strength bolt j via the gusset plate h. There is a joint construction method of joining and then fillet welding to form a beam-column joint. In addition, the code | symbol d in a figure is a backing metal, e is a scallop, f is a welding line, g is an end tab.

However, the beam-to-column joint and the beam-to-column connection method have several problems as described below, and reduce the toughness of steel beams. The width of the diaphragm c to which the flange a ′ of the H-shaped steel beam a is joined is larger than the width of the beam flange a ′, and the welding line f of the beam flange a ′ is along the width direction of the diaphragm c. It is orthogonal to the material axis direction of a. Therefore, as shown in FIG. 11B, the welding line f exists at a position (range) α at which the distribution of the stress σ generated in the axial direction of the beam flange a ′ by the external force acting on the H-shaped steel beam a is maximized. Will be. Therefore, the occurrence of welding defects in the welded portion (joined portion) where the stress is maximum is higher than that of the base material, and the possibility that the welded portion is broken before the base material reaches the breaking strength is large. Incidentally, the symbol β indicating the stress distribution coincides with the projection size of the diaphragm c. In general, a scalloping method of providing a scalloped e on the beam web a ″ is adopted in order to avoid deterioration of the material of the beam-to-column joint. However, the provision of the scalloped e causes a cross-sectional defect in the beam web a ″. In addition, there is a problem that axial strain is concentrated on the beam flange a 'of the scallop portion, the portion concerned reaches the breaking strength early, and the breaking easily occurs. Also,
There is a possibility that the fracture may occur earlier due to a welding defect of the welding line f at the scallop portion or a stress concentration at the scallop bottom.

[0004]

In view of the above and other problems, a beam web as shown in FIGS. 14A and 14B has been proposed as a method of improving the toughness of a beam and preventing early fracture of a steel beam. 15A and 15B, a non-scallop construction method using no scallops is proposed.

However, in the construction method for improving the shape of the scallop e shown in FIGS. 14A and 14B, it is impossible to reduce the stress concentration generated on the beam flange a 'of the scallop part, and the plastic region hardly spreads. Steel beams fail with low toughness values because they reach rupture strength early. Therefore, the above problems cannot be solved. FIG.
The non-scallop construction method shown in FIGS. 5A and 5B eliminates stress concentration at the end of the beam flange a 'of the H-shaped steel beam, thereby expanding the plastic region and improving plasticity. I can. However, the welding line f is still present at the position where the stress generated in the direction of the material axis of the beam flange a ′ is maximum (FIG. 11B), and the above problem still remains.

Accordingly, an object of the present invention is to integrally connect a reinforcing plate to a flange of an H-shaped steel beam or to change the width of the H-shaped steel beam itself, thereby moving the beam from the end to the center of the beam span. By gradually reducing the cross-sectional area, the stress distribution caused by the external force acting on the beam is prevented from being maximized at the welded portion where the scallop, the backing metal, the end tab, etc. of the beam-column joint are present, and the early stage of the beam flange is prevented. An object of the present invention is to provide a steel beam-column joint and a beam-column joint construction method capable of minimizing fracture.

[0007]

Means for Solving the Problems As means for solving the problems of the prior art, a steel beam-to-column joint according to the first aspect of the present invention is a steel-framed joint formed by joining a steel column and a steel beam. In the beam-column joint, the steel beam is characterized in that the cross-sectional area is gradually reduced from the end to the center of the span.

[0008] The steel beam-column joint according to the second aspect of the present invention,
The steel beam according to claim 1 is an H-beam, and a reinforcing plate whose cross-sectional area gradually decreases from the beam end toward the center of the span is welded to the flange of the H-beam. It is characterized by the following. In the steel beam-to-column joint according to the third aspect of the invention, the steel beam according to the first aspect is an H-shaped steel beam, and the reinforcing plate whose cross-sectional area gradually decreases from the beam end toward the center of the span, It is characterized by being joined by welding along the flange and the web of the H-shaped steel beam.

The steel beam-column joint according to the invention of claim 4 is
The steel beam described in claim 1 is an H-shaped steel beam, and the flange thickness of the H-shaped steel beam is gradually reduced from the beam end toward the center of the span. According to a fifth aspect of the invention, there is provided a steel beam-to-column connection, wherein the steel beam described in the first aspect is an H-shaped steel beam, and the flange width of the H-shaped steel beam is from the beam end toward the center of the span. It is characterized by being gradually reduced.

[0010] The steel beam-column joint according to the invention of claim 6 is characterized in that:
The reinforcing plate according to claim 2 is characterized in that the reinforcing plate is welded along the upper surface of the upper flange and the lower surface of the lower flange of the steel beam. According to a seventh aspect of the present invention, there is provided a steel beam-to-column joint, wherein the reinforcing plate according to the second aspect is welded to a steel beam in a manner that the reinforcing plate stands perpendicular to a flange surface of the steel beam.

[0011] The steel beam-column joint according to the invention of claim 8 comprises:
The steel plate beam joint according to claim 2, wherein the reinforcing plate according to claim 2 is welded along both edges of the upper flange and the lower flange of the steel beam. The steel beam-column joint according to the invention of claim 9 is:
The shape of the steel beam according to any one of claims 1 to 8,
From the end to the center of the span, the change in the cross-sectional area is sharpened to the position where the stress generated by the external force acting on the steel beam is maximized, and the change in the cross-sectional area is made slower thereafter. And

According to a tenth aspect of the present invention, there is provided a beam-column joint construction method for connecting a steel column and a steel beam, wherein the steel column is cut from a beam end to a beam span central portion. It is characterized by joining steel beams whose area is gradually reduced. According to a eleventh aspect of the present invention, the steel beam according to the tenth aspect is an H-shaped steel beam, and the reinforcing plate whose cross-sectional area gradually decreases from the beam end toward the center of the span is the H-shaped steel beam. And the H-shaped steel beam is connected to a steel column by welding.

According to a twelfth aspect of the present invention, the steel beam described in the tenth aspect is an H-shaped steel beam, and the reinforcing plate whose cross-sectional area gradually decreases from the beam end toward the center of the span is provided by the H-beam. It is characterized by joining by welding along a flange and a web of a shaped steel beam, and joining the H-shaped steel beam to a steel column. In the beam-column joint construction method according to claim 13, the steel beam described in claim 10 is an H-shaped steel beam, and the H-shaped steel beam whose flange thickness is gradually reduced from the beam end toward the center of the span is a steel beam. It is characterized by joining to a pillar.

According to a fourteenth aspect of the present invention, the steel beam according to the tenth aspect is an H-shaped steel beam, and the flange width is gradually reduced from the end of the beam toward the center of the span.
It is characterized in that a shaped steel beam is joined to a steel column. Claim 1
According to a fifth aspect of the present invention, a reinforcing plate according to the eleventh aspect is characterized in that the reinforcing plate is welded along the upper surface of the upper flange and the lower surface of the lower flange of the steel beam.

According to a sixteenth aspect of the present invention, the reinforcing plate according to the eleventh aspect is characterized in that the reinforcing plate is welded to a steel beam by standing upright on a flange surface. According to a seventeenth aspect of the present invention, the reinforcing plate described in the eleventh aspect is joined by welding along both edges of the upper flange and the lower flange of the steel beam.

According to an eighteenth aspect of the present invention, there is provided a beam-to-column connection method, wherein the shape of the steel beam according to any one of the tenth to seventeenth aspects is changed by an external force acting on the steel beam from its end toward the center of the span. It is characterized in that the cross-sectional area change is sharply increased to a position where the generated stress becomes maximum, and thereafter, the cross-sectional area change is slow.

[0017]

Embodiments and examples of the present invention will be described below with reference to the drawings. 1A-
C shows a first embodiment of a steel beam-column joint which is formed by joining a steel column 2 and a steel beam 1. An H-shaped steel beam 1 is preferably used for the steel beam 1, and an upper flange 1a of the beam 1 is used.
The reinforcing plate 11 is integrally joined along the upper surface of
Along the upper surface of the lower flange 1a, reinforcing plates 21 and 21 are provided.
Are integrally joined. The reinforcing plates 11 and 12
No. 1 has a sectional area gradually reduced from the beam end toward the center of the span. The steel column 2 has a beam flange 1
The steel pipe column 2 provided with the diaphragm 3 at the position a is used. In addition, as for the said steel beam 1, assembling beams other than H-shaped steel beams are suitably implemented. The steel column 2 is suitably implemented as an H-shaped steel column in addition to a steel tube column. The reinforcing plate 1
A steel plate is preferably used for 1,21. The same idea is applied to the following embodiments. Reference numeral 6 in the figure is a backing money,
7 is scallops.

The reinforcing plates 11 and 21 are joined along the flange 1a so as to protrude by an amount corresponding to the projecting dimension of the diaphragm 3 so that the ends thereof are in direct contact with the outer surface of the steel pipe column 2. When the shape of the reinforcing plate 11 is viewed in a plan view, the range H from the end to the position X where the stress generated by the external force acting on the H-shaped steel beam 1 is maximized has the same width-determining edges. The change in the cross-sectional area, which narrows the width at the curvature, is made abrupt, and the range H ′ near the center of the span beyond that is made slow in the change in the cross-sectional area, and is formed in a so-called trumpet shape (FIG. 1B). Further, the reinforcing plate 11
Is slightly wider than the width of the flange 1a. On the other hand, when the shape of the reinforcing plate 21 is viewed in a plan view, as shown in FIG.
In the range H up to the position X where the stress generated by the external force acting on the section steel beam 1 is maximized, the cross-sectional area change in which only one edge is reduced in width is sharpened, and the range H ′ near the center of the span earlier than that is cut off. The area change is slow, and the reinforcing plate 11 is formed in a shape as if the reinforcing plate 11 is divided into two equal parts.
Thickness and length (H + H ′) of the reinforcing plates 11 and 21
Although it depends on the size of the flange 1a and the web 1b of the H-shaped steel beam 1, the thickness and the length are sufficient to form a large plasticized region at the end of the beam flange 1a. Although the cross-sectional area changes of the reinforcing plates 11 and 21 are formed in a curved shape, the cross-sectional area changes may be formed in a straight line as shown in FIGS. 2B and 2C. The same idea is applied to the following embodiments.

Therefore, in the joining method of the steel beam-to-column joint, the flanges 1a, 1a of the H-shaped steel beam 1 are brought into contact with the diaphragms 3, 3 of the steel pipe column 2, and first, the beam web 1b is connected. The gusset plate 4 of the steel pipe column 2 is joined to the gusset plate 4 with high-strength bolts 5, and then the contacted portions are joined by welding. Then, the reinforcing plate 11 is placed along the upper surface of the upper flange 1a so that the end thereof is in contact with the outer surface of the steel pipe column 2, and is welded to the contact surface of the upper flange 1a and the steel pipe column 2. Reinforcement plates 21, 21
Similarly, along the upper surfaces of the beam web 1b and the lower flange 1a, the ends thereof are placed so as to abut against the outer surface of the steel pipe column 2,
The beam web 1b, the lower flange 1a, and the contact surface of the steel pipe column 2 are welded and joined to complete the steel column beam joining method. Of course, the beam web 1b is connected to the gusset plate 4
And the high-strength bolts 5 are joined to form a temporary fixing state, and then the contact portions and the reinforcing plates 11 and 21 are welded and joined, and finally, the high-strength bolts 5 are fully tightened. The beam web 1b can be directly welded to the contact surface of the steel pipe column 2 without using the gusset plate 4 and the high-strength bolt 5. The same idea is applied to the following embodiments.

The steel column-to-column joint constructed as described above has a stress σ generated by an external force acting on the H-shaped steel beam 1.
11A, the distribution does not become maximum at the welding point α where the scallops 7 and the backing metal 6 are present, but becomes maximum at a position X slightly closer to the center of the span. This is because the cross-sectional area of the end of the H-shaped steel beam 1 was increased by integrally welding the reinforcing plates 11 and 21 to the flange 1a and the like. As a result, the plasticization of the H-shaped steel beam 1 greatly progresses, and the early fracture of the beam flange 1a can be suppressed as much as possible. Of course, the magnitude of the stress concentration generated in the scallop portion is also smaller than the maximum stress point generated in the H-shaped steel beam 1, so that the scallop portion does not break.

The jointing method of the steel beam-column joints may be carried out by welding the reinforcing plates 11 and 21 at a factory in advance in addition to the field welding as described above. in this case,
As shown in FIG. 3, a steel column protruding portion 22 having substantially the same shape as the H-shaped steel beam 1 is welded to a steel column 2 at a factory, and reinforcing plates 11 and 21 are explained on the steel column protruding portion 22 with reference to FIG. 1. Welding is performed in the same manner. Then, on the spot, the flanges 1a, 1a of the H-shaped steel beam 1 are brought into contact with the flange portions 22a, 22a of the steel column protruding portion 22,
The beam web 1b is joined to the gusset plate 4 of the steel pipe column protruding portion 22 with the high-strength bolt 5, and then the contacted portions are joined by welding to complete the steel beam-column joining method (second example). Example). According to this construction,
Since the reinforcing plate can be welded in a free welding position, for example, as shown in FIG.
2 along the lower surface of the lower flange 22a.
Can be carried out by welding (third embodiment).
In these steel beam-column joints, the stress σ generated by the external force acting on the H-shaped steel beam 1 is, as shown in FIG. 11A, the welding in which the scallop 7 and the backing metal 6 are present as in the first embodiment. Since it does not reach the maximum at the point α but reaches the maximum at the position X slightly closer to the center of the span, the same effect as the steel beam-column joint described in the first embodiment can be expected.

FIGS. 5A and 5B show a fourth embodiment of a steel beam-column joint. As the steel beam 1 and the steel column 2, an H-shaped steel beam 1 and a steel tube column 2 provided with a diaphragm 3 at a position of a beam flange 1a are used as in the first embodiment. Upper surface of upper flange 1a and lower flange 1 of H-shaped steel beam 1
a reinforcing plate 21 used in the first embodiment
And are integrally joined to the upper and lower flanges 1a, 1a by welding. The reinforcing plate 2
Reference numerals 1 are used for each of the upper flange 1a and the lower flange 1a, two in total, and four are arranged at substantially equal distances in parallel with respect to the beam web 1b in plan view. As in the first embodiment, the reinforcing plate 21 has its end protruded by the protrusion of the diaphragm 3 and is joined to the flange 1a by welding. The thickness and length (H + H ′) of the reinforcing plate 21 differ according to the size of the flange 1a and the web 1b of the H-shaped steel beam 1 as in the first embodiment, but at the end of the beam flange 1a. The plate thickness and length are sufficient to form a large plasticized region.

Therefore, in the joint construction method of the steel beam-column joint, the flanges 1a, 1a of the H-shaped steel beam 1 are brought into contact with the diaphragms 3, 3 of the steel pipe column 2, and first, the beam web 1b is attached. The gusset plate 4 of the steel pipe column 2 is joined to the gusset plate 4 with high-strength bolts 5, and then the contacted portions are joined by welding. Then, a reinforcing plate 21 is placed on the upper surface of the upper flange 1a and the upper surface of the lower flange 1a so that the end thereof is in contact with the outer surface of the steel pipe column 2 and is welded to the contact surface of the upper flange 1a and the steel pipe column 2 respectively. The joint is completed to complete the steel beam-column joint construction method.

The steel column-to-column joint thus constructed is subjected to a stress σ generated by an external force acting on the H-shaped steel beam 1.
However, as shown in FIG. 11A, as in the first embodiment, the maximum does not occur at the welded portion α where the scallop 7 and the backing metal 6 are present, but at the position X slightly closer to the center of the span. Therefore, the same effect as the steel beam-column joint described in the first embodiment can be expected.

FIG. 6 shows an embodiment in which the arrangement position of the reinforcing plate 21 used in the fourth embodiment is changed.
The reinforcing plate 21 as shown in FIGS.
Steel beam-to-column joints (No. 5) that are vertically welded to the upper surface of the upper flange 1a and the lower surface of the lower flange 1a
Example) As shown in FIGS. 7A and 7B, the reinforcing plate 21 is connected to the flange 1 a of the H-shaped steel beam 1 and the web 1.
Steel beam-to-column joint welded along b (sixth embodiment)
And the reinforcing plate 21 as shown in FIGS.
Are connected to the upper flange 1a and the lower flange 1a of the H-shaped steel beam 1.
There is a steel beam-to-column beam joint (seventh embodiment) welded along both edges of the column. As shown in FIG. 11A, in the fifth to seventh embodiments, as in the first embodiment, the maximum value is not obtained at the welded portion α where the scallop 7 and the backing metal 6 are present. Since the maximum value is obtained at the shifted position X, the same effect as that of the steel beam-column joint described in the first embodiment can be expected. Of these, the fifth and sixth embodiments are implemented by welding the reinforcing plate 21 at a factory in advance, as in the above-described second and third embodiments.

FIGS. 9A and 9B show an eighth embodiment of the steel beam-column joint. As the steel beam 1 and the steel column 2, an H-shaped steel beam 1 and a steel tube column 2 provided with a diaphragm 3 at a position of a beam flange 1a are used as in the first embodiment. The thickness of the flange 1a of the H-shaped steel beam 1 is gradually reduced in cross section from the end to the center of the span. Looking at the shape of the flange 1a from the front, the range H from the end to the position X where the stress generated by the external force acting on the H-shaped steel beam 1 is maximized is a cross-sectional area change in which only one side is reduced in width. In the area H ′ near the center of the span, the change in the cross-sectional area is made slow, and the area beyond the area H ′ is formed in a flange having a constant thickness. The length (H + H ') at which the thickness and the cross-sectional area change at the end of the flange 1a varies depending on the size of the H-shaped steel beam 1, but a large plasticized region is formed at the end of the flange 1a. It should be thick and long enough to And the steel pipe column 2
The thickness of the diaphragm 3 is determined by the determined flange 1
The thickness at the end of “a” is substantially the same.

Therefore, the joint construction method of the steel beam-column joint is the same as that of the conventional ordinary beam-column joint method by connecting the flanges 1a, 1a of the H-shaped steel beam 1 to the diaphragms 3, 3 of the steel pipe column 2.
First, the beam web 1b is joined to the gusset plate 4 of the steel pipe column 2 with high-strength bolts 5, and then the contacted portions are joined by welding to form a steel column beam. Complete the joining method.

In the steel beam-to-column joint constructed as described above, the stress generated by the external force acting on the H-shaped steel beam 1 also causes the welding in which the scallop 7 and the backing metal 6 are present as in the first embodiment. It does not become the maximum at the location, and it becomes the maximum at a position slightly closer to the center of the span, and there is no risk of welding defects between the flange and the reinforcing plate. You can expect more effects

FIGS. 10A and 10B show a ninth embodiment of a steel beam-column joint. As the steel beam 1 and the steel column 2, an H-shaped steel beam 1 and a steel tube column 2 provided with a diaphragm 3 at a position of a beam flange 1a are used as in the first embodiment.
The cross-sectional area of the width of the flange 1a of the H-shaped steel beam 1 is gradually reduced from the end to the center of the span. When the shape of the flange 1a is viewed in a plan view, the range H from the end to the position X where the stress generated by the external force acting on the H-shaped steel beam 1 is maximized is such that both edges determining the width are equal. The change in the cross-sectional area that narrows the width with the curvature is sharpened,
A range H ′ near the center of the span earlier has a slower change in cross-sectional area, and the end is formed on a flange having a constant width and thickness. The length (H + H ′) at which the width and the cross-sectional area change at the end of the flange 1a is H-shaped steel beam 1
Although it depends on the size, the width and the length are sufficient to form a large plasticized region at the end of the flange 1a. In this embodiment, the width of the end of the flange 1a is
The width is approximately the same as the width of the diaphragm 3 of the steel pipe column 2.

Therefore, the joint construction method of the steel beam-column joint is the same as the conventional joint method of the beam-column joint, by connecting the flanges 1a, 1a of the H-shaped steel beam 1 to the diaphragms 3, 3 of the steel pipe column 2.
First, the beam web 1b is joined to the gusset plate 4 of the steel pipe column 2 with high-strength bolts 5, and then the contacted portions are joined by welding to form a steel column beam. Complete the joining method.

In the steel beam-to-column joint constructed as described above, the stress generated by the external force acting on the H-shaped steel beam 1 also causes the welding in which the scallop 7 and the backing metal 6 are present as in the first embodiment. It does not become the maximum at the location, and it becomes the maximum at a position slightly closer to the center of the span, and there is no risk of welding defects between the flange and the reinforcing plate. You can expect more effects

[0032]

According to the steel beam-column joint and the beam-column connection method of the present invention, a reinforcing plate is welded to a flange of an H-shaped steel beam, or the thickness of the flange itself is changed. By gradually reducing the cross-sectional area from the beam end to the center of the beam span, if the stress generated by the external force acting on the beam is maximized at the welded portion where the scallop, backing metal, end tab, etc. exist at the beam-column joint In addition, since a large plasticized area can be formed at the end of the flange, the breaking strength and toughness value of the beam flange and thus the steel beam can be greatly improved compared to the conventional, and the early fracture of the flange can be minimized. Can be suppressed.

[Brief description of the drawings]

FIG. 1A is a front view showing a first embodiment, FIG. 1B is a plan view thereof, and FIG. 1C is a right side view of FIG.

FIGS. 2A to 2C are plan views each showing a shape of a reinforcing plate.

FIG. 3 is a front view showing a second embodiment.

FIG. 4 is a front view showing a third embodiment.

FIG. 5A is a front view showing a fourth embodiment, and FIG. 5B is a plan view thereof.

FIG. 6A is a front view showing a fifth embodiment, and FIG. 6B is a plan view thereof.

7A is a front view showing the sixth embodiment, FIG. 7B is a plan view of the same, and FIG. 7C is a right side view of A.

FIG. 8A is a front view showing a seventh embodiment, and FIG. 8B is a plan view thereof.

FIG. 9A is a front view showing an eighth embodiment, and FIG. 9B is a plan view thereof.

FIG. 10A is a front view showing a ninth embodiment, and FIG. 10B is a plan view thereof.

FIGS. 11A and 11B are stress distribution diagrams each showing a relationship between a stress generated by an external force acting on a steel beam and a distance from a beam end;

12A is a front view showing a conventional technique, FIG. 12B is a plan view of the same, and FIG. 12C is a right side view of A.

13A is a front view showing a conventional technique, FIG. 13B is a plan view of the same, and FIG. 13C is a right side view of A.

14A and 14B are front views in which the shape of the scallops is improved.

FIGS. 15A and 15B are front views each showing a beam-column joint formed by a non-scallop construction method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 H-beam 1a Beam flange 1b Beam web 2 Steel column 3 Diaphragm 4 Gazette plate 5 High-strength bolt 6 Backing metal 7 Scallop 11 Reinforcement plate 11 'Reinforcement plate 21 Reinforcement plate 21' Reinforcement plate 22 Steel column protrusion 22a Projection Part flange 22b Projection part web

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Hiroshi Une 1-5-1, Otsuka, Inzai City, Chiba Prefecture Inside Takenaka Corporation Technical Research Institute

Claims (18)

[Claims] 1. A steel beam-column joint comprising a steel column and a steel beam, wherein the cross section of the steel beam is gradually reduced from the end to the center of the span. The steel beam-column joint. 2. The steel beam is an H-shaped steel beam, and a reinforcing plate whose cross-sectional area is gradually reduced from an end of the beam toward the center of the span is welded to the flange of the H-shaped steel beam. The steel beam-column joint according to claim 1, wherein: 3. The steel beam is an H-beam, and a reinforcing plate whose sectional area gradually decreases from the beam end toward the center of the span is welded along the flange and the web of the H-beam. The steel beam-column joint according to claim 1, wherein: 4. The steel beam according to claim 1, wherein the steel beam is an H-shaped steel beam, and the flange thickness of the H-shaped steel beam is gradually reduced from the beam end toward the center of the span. Steel column beam joints described. 5. The steel beam according to claim 1, wherein the steel beam is an H-shaped steel beam, and the flange width of the H-shaped steel beam is gradually reduced from the beam end toward the center of the span. Steel column beam joints described. 6. The steel beam-column joint according to claim 2, wherein the reinforcing plate is welded along the upper surface of the upper flange and the lower surface of the lower flange of the steel beam. 7. The steel beam-column joint according to claim 2, wherein the reinforcing plate is vertically welded to the surface of the flange of the steel beam and welded. 8. The steel beam-column joint according to claim 2, wherein the reinforcing plate is joined by welding along both edges of the upper flange and the lower flange of the steel beam. 9. The shape of the steel beam is such that the cross-sectional area changes sharply from the end to the center of the span to the position where the stress generated by the external force acting on the steel beam is maximized, and the cross section is cut off further. The steel beam-column joint according to any one of claims 1 to 8, wherein an area change is slow. 10. A steel beam-column connection method comprising joining a steel column and a steel beam, wherein a steel beam having a sectional area gradually reduced from a beam end portion to a beam span center portion is provided on the steel column. A steel column-beam joint construction method characterized by joining. 11. A steel beam is an H-beam, and a reinforcing plate having a sectional area gradually reduced from an end of the beam toward the center of the span is welded to a flange of the H-beam and welded to the H-beam. 11. The beam is connected to a steel column.
Steel beam-to-column connection method described in 1. 12. An H-shaped steel beam is used as a steel beam, and a reinforcing plate whose cross-sectional area is gradually reduced from an end of the beam toward the center of the span is joined by welding along a flange and a web of the H-shaped steel beam. The method according to claim 10, wherein the H-shaped steel beam is joined to a steel column. 13. An H-shaped steel beam, wherein the thickness of the flange is gradually reduced from the end of the beam toward the center of the span.
2. The steel beam is joined to a steel column.
0. The steel column-beam joint construction method described in 0. 14. An H-shaped steel beam, wherein the flange width is gradually reduced from the end of the beam toward the center of the span.
2. The steel beam is joined to a steel column.
0. The steel column-beam joint construction method described in 0. 15. The method according to claim 11, wherein the reinforcing plate is welded along the upper surface of the upper flange and the lower surface of the lower flange of the steel beam. 16. The method according to claim 11, wherein the reinforcing plate is vertically welded to the surface of the flange of the steel beam and is joined by welding. 17. The method according to claim 11, wherein the reinforcing plate is welded along both edges of the upper flange and the lower flange of the steel beam. 18. The shape of a steel beam is changed sharply from its end toward the center of the span to a position where the stress generated by an external force acting on the steel beam is maximized. The steel beam-column connection method according to any one of claims 10 to 17, wherein the change is slow.