JP7168855B2 - Welding Assembled H-Shaped Section Beam - Google Patents

Description

The present invention relates to a welded assembled H-section beam that is joined to a column.

In steel-framed buildings in which beams, columns, and the like are made of steel-framed members, beams and columns are sometimes joined at a construction site during construction. In particular, when an H-section beam is used as the beam, the ends of the web of the H-section beam and the column are welded or bolted at the construction site, and the ends of the upper and lower flanges of the H-section beam and the diaphragm of the column are connected. Beam end joints are often formed by welding. At this time, in order to weld the end of the lower flange of the H-section beam to the column, the end of the web of the H-section beam is provided with a welding hole, usually called a scallop. The scallop is formed by partially notching the end of the web of the H-section beam near the lower flange of the H-section beam, and the weld between the lower flange of the H-section beam and the column. are formed across the web of the H-section beam through this scallop.

As the H-shaped cross-section beam, a welded H-shaped cross-section beam may be used. The welded assembled H-section beam is formed by welding the intersections of a pair of upper and lower flanges and a web. For this reason, at the intersections of the pair of upper and lower flanges and the web, connecting portions are formed by the weld metal so as to be wide in the thickness direction of the web.

By the way, there is a possibility that the lower flange of the H-shaped cross-section beam may break during an earthquake due to the concentration of strain on the scallops of the beam end joints as described above, and measures to prevent this are required. For this reason, conventionally, measures have been taken to reinforce the shape of the scallops and to reinforce the scallops so as to reduce the concentration of strain on the scallops.

For example, in Non-Patent Document 1, as a scallop shape that can alleviate the concentration of strain on the scallop, a shape that combines arcs with two curvature radii, and the curvature radius of the arc of the portion connected to the flange is A compound circular scallop is disclosed having a shape of 10 mm and an arc radius of curvature remote from the flange of 35 mm. Furthermore, in Non-Patent Document 1, as a scallop shape that can alleviate the concentration of strain on the scallop, the radius of curvature of the 1/4 circular arc of the portion connected to the flange is 10 mm, and the A modified B-type scallop is disclosed which is shaped with an extending straight portion. In addition, in Non-Patent Documents 2 and 3, as a scallop shape that can alleviate the concentration of strain on the scallop, a circular arc portion and a flange that extends linearly from the circular arc portion and is connected to the scallop A scalloped shape is disclosed.

On the other hand, in Patent Document 1, as a measure to reinforce the scallops, a steel frame column beam flange weld joint is a groove consisting of a beam flange, a plate-shaped member joined to the outside of the flange, and a through diaphragm of the steel frame column. A structure is disclosed in which the joint is formed by full penetration welding, the plate member is a tapered plate whose thickness linearly decreases from the thick portion to the thin portion, and the web of the beam is provided with scallops.
Further, Patent Document 2 discloses a structure in which the scallops are filled by welding or the like as a countermeasure for reinforcing the scallops.

JP 2013-7194 A JP 2015-224427 A

Architectural Institute of Japan: Technical Guideline for Steel Construction, Factory Production Edition, 5th Edition, February 2007 Tadao Nakagome, Tetsuya Fujita: Mechanical Performance of Ends of Rolled H-beams Welded and Joined to Square Steel Pipe Columns by Diaphragm Type. Proceedings No. 455, January 1994 J. M. Rickles, JW. Fisher, Le-Wu Lu, E.M. J. Kaufmann; Development of improved welded moment connections for earthquake resistant design, Journal of Constructional Steel Research, 58 (2002), 565-604

However, the scallops disclosed in Non-Patent Documents 1 to 3 have the problem that strain is concentrated in the vicinity of the portion where the scallop and the lower flange of the H-section beam are connected, which is usually called the scallop bottom. That is, there is a problem that strain is concentrated on the scalloped bottom, and cracks are generated in this portion during an earthquake, and the cracks propagate to the outer surface of the lower flange of the H-shaped cross-section beam. If this crack progresses to the outer surface of the lower flange of the H-shaped cross-section beam, the lower flange of the H-shaped cross-section beam will be fractured starting from this crack, which may impair the seismic performance of the steel frame building. For this reason, a scallop shape capable of alleviating the concentration of strain on the scallop bottom is currently in demand. In addition, if strain is concentrated on the scalloped bottom and cracks occur in this part during an earthquake, the cracks that have occurred are difficult to see because there are other steel frames such as columns to which the H-shaped cross-section beams are joined. , there is a problem that diagnosis of damage after an earthquake becomes difficult.
In addition, in the structure as disclosed in Patent Document 1, although it is possible to reduce the stress at the ends of the beams, there is the problem that it takes time and effort to prepare and connect tapered plates for reinforcement. Similarly, even in the structure of Patent Document 2, there is a problem that it takes time and effort to fill the scallops by welding or the like for reinforcement.

On the other hand, in the weld assembled H-section beam, since a pair of the connecting portions are provided with the web sandwiched in the thickness direction thereof, there may be an unwelded portion between the pair of connecting portions. That is, since a pair of connecting portions are provided sandwiching the web in its thickness direction, the weld metal does not completely melt at the inner surface of the flange that is in contact with the web at the center in the thickness direction of the web or in the vicinity thereof, that is, at the root portion, It may have unwelded parts.
In addition, since the scallop bottom is almost flush with the inner surface of the flange, the non-welding portion described above is exposed on the scallop bottom, and a crack occurs and propagates from the tip of the non-welding portion during an earthquake, leading to fracture of the steel beam. Sometimes.
In order to prevent such scallop rupture, it is necessary to deepen the penetration of the weld metal in the connecting portion and eliminate the unwelded portion. However, if the amount of heat input is increased to deepen the penetration, the toughness of the connection deteriorates and the risk of fracture increases.

The present invention has been made in view of the above circumstances, and can suppress the occurrence of cracks in the scalloped bottom, and can avoid early breakage of the beam end joint when the beam end is joined to the column. It is an object of the present invention to provide a weld assembled H-section beam.

To achieve the above object, a welded assembly H-section beam according to the present invention includes a web, a pair of upper and lower flanges provided at both ends of the web in the web width direction, the web and the pair of upper and lower flanges. A welded assembled H-section beam comprising a connection that welds and joins a
A scallop is provided at an end of the web in the web width direction,
The scallops are
a first open end located on the lower flange side of the pair of upper and lower flanges;
a second open end located on a side opposite to the first open end;
a first open edge extending from the first open end away from the end of the web;
a second open edge extending from the second open end and away from the end of the web;
a third opening edge connecting the first opening edge and the second opening edge;
The first opening edge is formed in an arc shape so as to intersect with a toe on the web side of the connecting portion provided at a portion where the web and the lower flange intersect. has a first arc portion at one end on the open end side of the lower flange, the tangent of which is parallel to the inner surface of the lower flange;
The third opening edge has a second circular arc portion formed in an arc shape connecting the first opening edge and the second opening edge,
The radius of curvature of the first arc portion is larger than the radius of curvature of the second arc portion.

Since one of the objects of the present invention is to reduce the concentration of strain on the bottom of the scallops, the scallops may of course be provided on the upper flange side at the end of the web.

In the present invention, with respect to the radius of curvature of the second arc portion in the third opening edge connecting the first opening edge and the second opening edge, on the lower flange side By increasing the curvature radius of the first circular arc portion at the first opening edge located, shear deformation of the web can be easily caused around the scallop. As a result, it is possible to alleviate the concentration of strain on the scalloped bottom, and suppress the occurrence of cracks in the scalloped bottom. Here, the scalloped bottom in the present invention means the vicinity of one end of the first circular arc portion on the first opening end side. Furthermore, since the first opening edge is formed in an arc shape so as to intersect the web-side toe portion of the connecting portion, the thickness of the H-shaped cross section in the width direction is relatively increased. A ductile crack can be intentionally initiated at the web-side toe of the small joint. Since this ductile crack does not propagate to the flange and stably propagates in the axial direction along the toe portion on the web side of the connection portion, which has a smaller tensile stress than the flange, the lower It is possible to prevent the flange from breaking and impairing the seismic performance of the steel frame building.

Further, in the above configuration of the present invention, a pair of the connecting portions are provided with the web sandwiched therebetween in the thickness direction thereof, and a non-welding portion is provided between the pair of connecting portions, and the width of the non-welding portion is set to the width of the web. The first open end of the scallop may be 0.94 times or less of the plate thickness, and the first open end of the scallop may be on the surface of the connecting portion and the web at a position closer to the web side than the inner surface of the lower flange.
Furthermore, the width of the unwelded portion may be 1.0 times or less the thickness of the web, that is, the width of the unwelded portion may be suppressed within the range of the thickness of the web.

Here, the reason why the width of the unwelded portion is set to 0.94 times or less of the thickness of the web is that if the width of the unwelded portion exceeds 0.94 times the thickness of the web, the distortion of the scalloped bottom during an earthquake is abrupt. This is because Furthermore, since welding with an excessively large unwelded portion tends to cause welding defects such as poor penetration and weld cracks, the width of the unwelded portion should be 0.94 times or less the thickness of the web plate. is desirable.

According to such a configuration, the first open end of the scallop is located closer to the web side than the inner surface of the lower flange, so the unwelded portion of the connecting portion does not appear at the first open end. Therefore, stress concentration at the open end of the unwelded portion during an earthquake can be avoided, and the presence of the unwelded portion in the connecting portion is permissible. On the other hand, by limiting the width of the unwelded portion to 0.94 times or less of the web plate thickness, it is possible to prevent the width of the unwelded portion from becoming too large, reduce the distortion of the scalloped bottom, and avoid welding defects. . Therefore, by using the scallop according to the present invention to allow the existence of the non-welded part under certain conditions, the welding heat input when welding the flange and the web can be reduced, and the weld toughness of the connecting part can be reduced. can be increased, the risk of early rupture during an earthquake is reduced. In addition, since the size of the connecting portion can be reduced by configuring the connecting portion by low heat input welding, the restraint by the connecting portion of the scallop bottom is reduced, and furthermore, the position of the web side toe of the first opening end and the connecting portion can be reduced. , the shear strain at the toe on the web side tends to increase, and cracks occur at the toe on the web side. Furthermore, during an earthquake, a ductile crack that occurs at the scallop bottom may grow under repeated loads and reach the unwelded portion, exposing the unwelded portion at the tip of the crack. According to the method, the ductile crack in the scallop can be stably propagated in the axial direction along the toe on the web side, so the initiation and propagation of the crack at the scallop bottom are suppressed. As a result, it is possible to prevent cracks from occurring and propagating from the unwelded portion during an earthquake.

Further, in the configuration of the present invention, the first circular arc portion and the second circular arc portion are tangent to a common arc formed by the first circular arc portion and the second circular arc portion. may be connected at any part.
According to such a configuration, the first circular arc portion and the second circular arc portion are continuously connected, so that the concentration of strain on the scallop bottom can be further alleviated, and the scallop It is possible to further suppress the occurrence of cracks in the bottom.

Further, in the configuration of the present invention, the first opening edge has a straight portion arranged in parallel with the inner surface of the lower flange that includes the first opening end and is closest to the first opening edge. may be connected to the linear portion at one end on the first opening end side of the circular arc portion.
According to such a configuration, a sufficient space for welding the lower flange and the column can be secured, the welding between the flange and the column can be stably performed, and welding defects can be prevented. can do.

Moreover, in the configuration of the present invention, the radius of curvature of the first circular arc portion may be 2.5 times or more the radius of curvature of the second circular arc portion.
According to such a configuration, it is possible to alleviate the strain concentration on the lower flange side of the scallops and stably suppress the occurrence of cracks from the scallops.

In addition, it is desirable that the size of the scallop is as small as possible in order to stably secure the strength of the beam end joint when the beam end of the welded H-shaped cross-section beam of the present invention is joined to a column or the like. However, from the viewpoint of welding workability between the flange and the column, the dimension of the scallop in the direction from the lower flange side to the upper flange side may be 15 mm or more.

The scallops are usually formed by cutting a portion of the web by cutting. In order to smooth the cutting surface of the circular arc portion and suppress the occurrence of cracks, it is necessary to make the radius of curvature as large as possible in terms of cutting. preferably. Therefore, the radius of curvature of the second arc portion may be 6 mm or more.

Effect of the Invention According to the present invention, it is possible to suppress the initiation and propagation of cracks to the scallop bottom in a welded assembled H-section beam, thereby preventing the fracture of the lower flange originating from the scallop bottom. In addition, when the beam end is joined to the column, breakage of the lower flange originating from the scallop bottom is prevented, so early breakage of the beam end joint can be avoided.

It is a perspective view which shows the outline|summary of the beam-end joint part of embodiment. FIG. 2 is a detailed view of part A in FIG. 1; FIG. 2 is a cross-sectional view cut along the cutting line BB in FIG. 1; FIG. 3 is a side view showing details of the scallops that are the first aspect of the embodiment; FIG. 11 is a side view showing details of the scallops that are the second aspect of the embodiment; (a) is a side view showing details of a scallop that is a third aspect of the embodiment, and (b) is a cross-sectional view taken along line CC in (a). (a) is a side view showing details of a scallop that is the fourth aspect of the embodiment, and (b) is a sectional view taken along line CC in (a). FIG. 3 is a model diagram showing the entire analytical model used in the examples. It is an explanatory view for explaining a bending angle. Analysis model No. 12 is a distribution diagram showing the equivalent plastic strain distribution in No. 12. FIG. Analysis model No. 45 is a distribution diagram showing the equivalent plastic strain distribution at 45. FIG. Analysis model No. 12 is a distribution diagram showing the plastic shear strain distribution in No. 12. FIG. Analysis model No. 24 is a distribution diagram showing the plastic shear strain distribution at 24. FIG. 7 is a graph showing the relationship between the ratio of the radius of curvature of the first circular arc portion to the radius of curvature of the second circular arc portion based on analysis results and the maximum equivalent plastic strain. It is a graph which shows the result of having analyzed the test body of the welding assembled H-shaped cross-section beam, and shows the relationship between the beam tip deformation amount and the equivalent plastic strain of the scalloped bottom. It is a graph showing the results of analysis of an analytical model of a welded assembly H-section beam with a small leg length in the height direction of the joint, and showing the relationship between the beam tip deformation amount and the maximum value of the equivalent plastic strain of the scalloped bottom. . This is a graph showing the results of analysis of an analytical model of a welded assembly H-section beam with a medium leg length in the height direction of the connecting part, showing the relationship between the amount of deformation at the tip of the beam and the maximum value of equivalent plastic strain at the scalloped bottom. is. This shows the results of analysis using an analytical model of a welded assembled H-section beam with a small joint and a welded assembled H-section beam with a medium leg length in the height direction of the joint. It is a graph which shows the relationship with the maximum value of the equivalent plastic strain of the scalloped bottom when the amount of deformation is 80 mm.

An embodiment according to the present invention will be described below.
In FIG. 1, a beam end of a weld assembled H-section beam 1 (hereinafter sometimes abbreviated as beam 1) is welded to a box-shaped cross section pillar 110 (hereinafter sometimes abbreviated as pillar 110). FIG. 2 is an enlarged view of the A circle portion in FIG. 1. FIG.
The beam end joint 100 is formed at a construction site, for example, and includes a column 110 and a beam 1 joined to the column 110 . The column 110 is configured by axially connecting a plurality of box-shaped column members 111 made of steel and column-to-beam joints 110a to which the beams 1 are connected. In addition, in this embodiment, the example which used the square steel pipe as the column material 111 is shown.
The column-to-beam joint portion 110a includes a column member 111A and a pair of diaphragms 112, 112 provided on both upper and lower end sides of the column member 111A and used for connection with the beam 1. As shown in FIG. The height dimension of the column member 111A used in the column-to-beam joint 110a is determined by the peripheral edges of the pair of diaphragms 112 and 112 and the axial ends of the pair of flanges 20 and 20 of the beam 1 to be connected, which will be described later. are large enough to face each other.
Each diaphragm 112 is a so-called through-diaphragm formed in a substantially rectangular plate shape. It is sandwiched by the material 111B. Each diaphragm 112 is integrated with the beam-to-column joint 110a and the pillar 111 by welding or the like in a state where the peripheral portion protrudes outward (horizontally) from the peripheral surface 111a of each pillar 111 .
The column-to-beam joint is not limited to a through-diaphragm type structure as in the present embodiment. The steel beam 1 may be connected via a column 110 or a diaphragm.

The beam 1 extends in one direction (horizontal direction) as a whole, and extends between the web 10 and both ends in the height direction perpendicular to the axial direction of the web 10 (hereinafter referred to as the web (10) in the direction perpendicular to the axial direction). The ends are sometimes called "rims".) It has a pair of upper and lower flanges 20, 20 connected to 10b.
The web 10 extends in the axial direction of the beam 1 with the direction orthogonal to the axial direction of the web 10 , that is, the web width direction as the height direction of the beam 1 . A pair of flanges 20 , 20 extend in the axial direction of the beam 1 and are connected to both upper and lower ends of the web 10 , that is, both edges 10 b , 10 b of the web 10 . Moreover, the pair of flanges 20 , 20 protrude from the web 10 at substantially right angles to the thickness direction of the web 10 at both upper and lower end portions of the web 10 . An axial end of the beam 1 is connected to the peripheral surface of the column 110 . Of the pair of flanges 20, 20, the lower flange 20 is called a lower flange, and the upper flange 20 is called an upper flange.
Here, in the present embodiment, the axial end of the beam 1 connected to the column 110 is referred to as an axial end (1a), and the web 10 and the flange 20 are connected to the column 110 at the axial end of the beam. The portions to be formed are referred to as shaft ends (10a, 20a), respectively.

As shown in FIG. 3, the welded assembled H-section beam 1 in this embodiment connects the web 10 and the pair of flanges 20, 20 at the intersections of the web 10 and the pair of flanges 20, 20. The connection part 30 which carries out is provided respectively. The connecting portion 30 welds and joins the web 10 and the pair of flanges 20, 20, respectively, and is formed by melting the welding material or the welding material and the base material. The connecting portions 30 are provided at both edges 10b, 10b of the web 10 between both web surfaces 11, 11 of the web 10 and the inner surfaces 21, 21 of the pair of flanges 20, 20, which are inner surfaces facing each other. formed. In other words, the connecting portions 30 are provided in pairs at the upper and lower edges of the web 10 so as to sandwich the web 10 in the thickness direction of the web 10 and sandwich the web 10 between the edges 10b, 10b of the web 10. It is provided on the surfaces 11,11.
Further, as shown in FIG. 3 , in this embodiment, the connecting portion 30 extends from the web toe portion 31 connected to the web surface 11 of the web 10 to the inner surface 21 of the flange 20 in the axial cross section of the beam 1 . It is formed in a triangular shape having a linear inclined surface connecting up to the flange toe portion 32 to be connected, and is further formed in an isosceles triangular cross section in this embodiment. The size of each side along the web surface 11 of the web 10 and the inner surface 21 of the flange 20 at the connecting portion 30, that is, the height direction (beam length direction) that is the distance from the inner surface 21 of the flange 20 to the web toe portion 31 The leg length s _w of the web 10 and the leg length s _f in the horizontal direction (flange width direction), which is the distance from the web surface 11 of the web 10 to the flange toe 32, are, for example, about 3 to 30 mm.

Note that the cross section of the connecting portion 30 is not limited to a triangular shape. The web toe 31 to the flange toe 32 may be connected by an arc-shaped concave curved surface, and the tangent to the concave curved surface at the web toe 31 and the flange toe 32 is the web surface 11 of the web 10 and the flange 20 . may be connected so as to be parallel to the inner surface 21 of the . Also, the web toe portion 31 and the flange toe portion 32 may be connected by a convex curved surface.
In this embodiment, as described above, the connecting portion 30 is formed by performing fillet welding, for example, between the web 10 and the flange 20. A welded portion is formed by each portion of and.

The beam 1 is connected to the pillar 110 by the end connection structure 200 . That is, as shown in FIG. 1, the end connection structure 200 includes a flange weld portion 40 for welding the axial end 20a of the flange 20 of the beam 1 to the column 110, and the axial end 10a of the web 10 of the beam 1 to the column 110. and a web weld 50 to be welded. In addition, on the lower surface side of the flange welded portion 40, a backing metal 45 is provided to prevent the molten metal forming the flange welded portion 40 from falling out from between the groove surface 40a of the flange 20 and the column 110. there is
Further, in this embodiment, the axial end 20a of the flange 20 is welded to the diaphragm 112 of the column 110, and the axial end 10a of the web 10 is welded to the peripheral surface 111a of the column material 111A forming the column-to-beam joint 110a. ing. In this manner, the beam end of the beam 1 is welded to the column 110 .

A scallop 60 is provided at the axial end 10a of the web 10 in the beam 1. As shown in FIG. The scallops 60 are formed on the axial end 10a side of the web 10 at both edges 10b, 10b on the side of the pair of flanges 20, 20, toward the axial end 20a side of the nearest flange 20 and the axial end 10a side of the web 10. , and are provided to penetrate through the web 10 in the thickness direction. Thereby, the flange welded portion 40 is formed from one end in the width direction of the flange 20 to the other end in the width direction across the web 10 through the scallop 60 . In addition, the web welded portion 50 is formed up to scallops 60 provided on both edges 10b, 10b of the web 10. As shown in FIG.
In this embodiment, the web 10 of the beam 1 is connected to the column 110 by welding its axial end 10a to the column 110, but the method of joining the axial ends of the web of the beam is limited to welding. It may be, for example, bolted.

As shown in FIG. 4, since the scallop 60 has an opening that opens toward the axial end 20a side of the nearest flange 20 and the axial end 10a side of the nearest web 10 as described above, two Includes an open end. That is, the first opening end 60a located on the nearest flange 20 side and the side opposite to the first opening end 60a, in other words, the center of the web 10 sandwiched between the pair of flanges 20, 20 in the web width direction and a flanking second open end 60b. More specifically, the first open end 60a is formed on the inner surface 21 side of the flange 20, and the second open end 60b is formed on the axial end 10a of the web 10, respectively.

The scallop 60 also has a first opening edge 61 , a second opening edge 62 and a third opening edge 63 . The first opening edge 61 includes a first opening end 60a and extends from the first opening end 60a in the axial direction of the beam 1 in a direction away from the axial end 1a. The second opening edge 62 includes a second opening end 60b and extends from the second opening end 60b in a direction away from the axial end 1a of the beam 1, that is, toward the axial center of the beam 1. . The third opening edge 63 connects the first opening edge 61 and the second opening edge 62 .

Specifically, the first opening edge portion 61 is formed in an arc shape so as to intersect the web toe portion 31 of the connecting portion 30, and the tangent line is the flange portion at one end 71a on the side of the first opening end 60a. It has a first arcuate portion 71 that is parallel to the inner surface 21 of 20 .
The shape of the second opening edge 62 is not particularly limited, but in the case of the present embodiment, it extends linearly from the second opening end 60b.
Also, the third opening edge 63 has a second circular arc portion 72 that curves from the first opening edge 61 toward the second opening edge 62 .
Here, it is desirable that the curvature radius R1 of the first circular arc portion 71 is 2.5 times or more the curvature radius R2 of the second circular arc portion 72. As shown in FIG. The reason why the radius of curvature R1 of the first arc portion 71 is set to 2.5 times or more the radius of curvature R2 of the second arc portion 72 is that the concentration of strain on the flange 20 side of the scallop 60 is alleviated. Therefore, it is possible to more stably suppress the occurrence of cracks from the scallops 60 .

In the scallop 60 formed by the first opening edge 61, the second opening edge 62 and the third opening edge 63, the direction in which the pair of flanges 20, 20 separate from each other (the height of the beam 1 It is desirable that the height dimension _Srh of the scallop 60 in the direction) be as small as possible in order to stably secure the proof stress of the beam end joint 100, but from the viewpoint of welding workability between the flange 20 and the column 110 , The dimension of the scallop 60 in the direction from the lower flange 20 side to the upper flange 20 side is preferably 15 mm or more. Further, the height dimension _Srh of the scallops 60 may be 35 mm or less in order to more efficiently transmit the moment to the web 10 as well and further reduce the strain concentration on the flange 20 side of the scallops 60 .
Further, the radius of curvature R2 of the second circular arc portion 72 may be 6 mm or more in consideration of cutting with a cutter when forming the scallops and ensuring workability.

More detailed aspects of the scallop 60 are described below.
FIG. 4 shows the scallop 60 of the first embodiment. As shown in FIG. 4, in the scallop 60 of the first aspect, the first opening edge 61 is disposed at a position on the nearest flange 20 side, and includes a first opening end 60a. It has a straight portion 73 and a first arc portion 71 connected to the first straight portion 73 .
The first straight portion 73 corresponds to the portion where the web 10 is cut out by the scallop 60 on the inner surface 21 of the nearest flange 20, and is included in the inner surface 21 of the nearest flange 20 in this embodiment. there is In addition, the first open end 60a is provided at the axial end 20a of the flange 20 that is closest thereto, and more specifically, the groove surface used when forming the flange weld portion 40 that is welded to the column 110. The end of 40a on the web 10 side is the first open end 60a.
The first circular arc portion 71 has a tangent line parallel to the inner surface 21 of the flange 20 at the position where it connects to the first straight portion 73, and gradually moves away from the flange 20 as the distance from the axial end portion 1a of the beam 1 increases. It is formed in a curved concave shape. The first arcuate portion 71 is connected to the first straight portion 73 and crosses the connecting portion 30, and a crossing portion 71c crosses the connecting portion 30, and from one end of the crossing portion 71c on the side opposite to the nearest flange 20, the web of the web 10 is formed. and a web forming portion 71 d formed along the surface 11 .

On the other hand, the second opening edge 62 has a second straight portion 74 that is formed in a straight line including the second opening end 60 b and extends along the axial direction of the beam 1 .
The third opening edge 63 has a second arc portion 72, and one end 72a of the second arc portion 72 is connected to the first arc portion 71 of the first opening edge 61. The other end 72b is connected to the second linear portion 74 of the second opening edge portion 62. As shown in FIG.
Here, the first arc portion 71 and the second arc portion 72 are connected at a portion where the arc formed by the first arc portion 71 and the arc formed by the second arc portion 72 are a common tangent line. there is Also, at the connecting portion between the second arc portion 72 and the second straight portion 74 , the tangent line of the arc forming the second arc portion 72 and the second straight portion 74 match. Thereby, the shape of the edge of the scallop 60 composed of the first opening edge 61, the second opening edge 62 and the third opening edge 63 is continuous.
In this embodiment, the height dimension _Srh of the scallop 60 is determined by the distance between the first straight portion 73 and the second straight portion 74 .

Also, FIG. 5 shows a scallop 60A of the second embodiment. In addition, after giving the same code|symbol about the structure same as a 1st aspect, description is abbreviate|omitted.
As shown in FIG. 5, the first opening edge 61 in the scallop 60A of the second aspect does not have a portion corresponding to the first linear portion 73 in the first aspect, and the first arc portion 71 One end 71a on the nearest flange 20 side is the first open end 60a. One end 71 a of the first circular arc portion 71 serving as the first open end 60 a is located on the inner surface 21 of the flange 20 , and the tangent line at the one end 71 a is parallel to the inner surface 21 of the flange 20 .
In this embodiment, the height dimension _Srh of the scallop 60 is determined by the distance between the one end 71 a of the first circular arc portion 71 and the second linear portion 74 .

Also, FIG. 6 shows a scallop 60B of the third embodiment. Similarly, the same reference numerals are assigned to the same configurations as in the first mode, and the description thereof is omitted.
As shown in FIG. 6( a ), in this embodiment, the groove surface 40 a used for forming the flange welded portion 40 gradually extends upward (strictly speaking, the shaft end portion 1 a of the beam 1 gradually increases upward). ), and one end of the groove surface 40a is located closer to the center in the web width direction than the inner surface of the nearest flange 20. One end of the groove surface 40a serves as a first open end 60a. That is, the first open end 60a of the scallop 60B is located on the surface of the connecting portion 30 and the web 10 at a position closer to the web 10 side than the inner surface of the lower flange 20. As shown in FIG.
Specifically, the scallop 60B is configured such that the first opening edge 61 includes a first straight portion 75 including the first opening end 60a and a first arc portion 71 connected to the first straight portion 75. , and the first straight portion 75 is separated from the inner surface 21 of the flange 20 by the amount that the first opening end 60a is located on the center side in the web width direction than the inner surface of the nearest flange 20 and is formed parallel to the inner surface 21 of the flange 20 .
Here, the scallop separation distance _Srf represented by the distance between the first straight portion 75 and the inner surface 21 of the flange 20 is at least the distance from the web toe 31 of the connecting portion 30 to the inner surface 21 of the flange 20. It is smaller than the leg length _sw in the lateral direction. Thereby, the first arc portion 71 connected to the first straight portion 75 intersects the web toe portion 31 .
In this embodiment, the height dimension _Srh of the scallop 60 is determined by the separation distance between the first straight portion 75 and the second straight portion 74 .

In the third aspect, as shown in FIG. 6(b), the welded assembled H-section beam 1 may have an unwelded portion 30a between the pair of connecting portions 30,30. That is, since the connecting portions 30, 30 are provided to sandwich the web 10 in the thickness direction, the inner surface of the lower flange 20 or the vicinity thereof, that is, the root portion, which is in contact with the web 10 at the center portion in the thickness direction of the web 10. The weld metal (welding material) may not be completely melted and may have an unwelded portion 30a.

The non-welded portion 30a is formed by the weld metal not completely melting into the connection portions 30, 30 provided with the web 10 interposed therebetween and the flange 20, which is the base material of the connection portions 30, 30. A part of the gap is in a so-called metal touch state or a slight gap is generated. As shown in FIG. 6(a), such a non-welding portion 30a may extend in the longitudinal direction (horizontal direction) of the flange 20, and the tip portion may open to the groove surface 40a. Such a non-welding portion 30a is likely to occur at the root portion of the connecting portion 30 when the web 10 and the flange 20 are welded together. At this time, the width W of the unwelded portion 30a is preferably kept within the plate thickness of the web 10, but the width W of the unwelded portion 30a is 0.94 times or less the plate thickness of the web 10 (web plate thickness). It is more preferable that

Also, FIG. 7 shows a scallop 60C of a fourth embodiment. In addition, after giving the same code|symbol about the structure same as a 3rd aspect, description is abbreviate|omitted.
As shown in FIG. 7( a ), the first opening edge 61 in the scallop 60C of the fourth aspect does not have a portion corresponding to the first linear portion 75 in the third aspect, and the first circular arc One end 71a of the portion 71 is the first open end 60a. One end 71a of the first circular arc portion 71 that becomes the first open end 60a is separated from the inner surface 21 of the flange 20 as in the third aspect, and the tangent line at the one end 71a is parallel to the inner surface 21 of the flange 20. It has become. That is, the first open end 60a of the scallop 60C is on the surface of the connecting portion 30 and the web 10 at a position closer to the web 10 side than the inner surface of the lower flange 20 is.
Here, the scallop separation distance _Srf represented by the distance between one end 71a of the first circular arc portion 71 and the inner surface 21 of the flange 20 is at least the distance from the web toe portion 31 of the connecting portion 30 to the inner surface 21 of the flange 20. is smaller than the leg length _sw in the height direction. Thereby, the first arc portion 71 connected to the first straight portion 73 intersects the web toe portion 31 .
In this embodiment, the height dimension _Srh of the scallop 60 is determined by the distance between the one end 71 a of the first circular arc portion 71 and the second linear portion 74 .

Further, as shown in FIG. 7(b), in the fourth aspect, as in the third aspect, the welded assembled H-section beam 1 has a non-welded portion 30a between the pair of connecting portions 30, 30. may have. The width W of the unwelded portion 30a is also 0.94 times or less the thickness of the web 10 (web thickness), as in the third aspect.

In the above first to fourth aspects, the first arc portion 71 of the first opening edge portion 61 and the second arc portion 72 of the third opening edge portion 63 are the same as the first arc portion 71 and the arc formed by the second arc portion 72 are connected at a common tangent line. However, the first arcuate portion 71 and the second arcuate portion 72 may not be connected at a common tangent portion, that is, they may be connected with an angle forming a boundary. Further, a linear portion is provided between the first circular arc portion 71 and the second circular arc portion 72, and the first circular arc portion 71 and the second circular arc portion 72 are indirectly connected. There may be.
Furthermore, although the second opening edge 62 is a linear portion in the present embodiment, it may be of any shape, such as an arc shape.

In the welded assembly H-shaped cross-section beam 1 as described above, the second arc portion 72 is provided in the third opening edge portion 63 connecting the first opening edge portion 61 and the second opening edge portion 62, A first arc portion 71 may be provided in the first opening edge portion 61 located on the side of the flange 20, and the first arc portion 71 may have a radius of curvature 2.5 times or more larger than that of the second arc portion 72. .
As a result, concentration of strain on the flange 20 side of the scallops 60 can be alleviated, and cracking from the scallops 60 can be suppressed. Since the first circular arc portion 71 is formed so as to intersect the web toe portion 31 of the connecting portion 30, even if a ductile crack occurs, the width is relatively narrow. Cracks can occur near the web toe 31 where the cross-section changes from the web 10 . In addition, even if a ductile crack occurs near the toe on the web 10 side, the generated crack is stably axially along the web toe 31 having a lower tensile stress than the flange 20. can propagate cracks. Therefore, the welded assembly H-shaped cross-section beam 1 as in this embodiment delays the initiation of initial cracks from the scallops without providing a separate structure for reinforcement, and in the unlikely event that an initial crack occurs. The ductile crack can be propagated so as not to lead to premature fracture even if the beam end joint 100 is joined to the column 1, and the safety of the beam end joint 100 can be increased.

Moreover, by setting the height dimension of the scallop 60 to 15 mm or more, workability of welding between the flange 20 and the column 110 can be improved.
In addition, by setting the height dimension of the scallop 60 to 35 mm or less, the moment can be transmitted more efficiently even in the web 10, so that the yield bending strength of the joint between the column 110 and the beam 1 can be improved. can. In addition, by keeping the height of the scallop 60 low, the moment can be transmitted more efficiently by the web 10, so that the strain concentration on the flange 20 side of the scallop 60 can be further alleviated.
Furthermore, since the first arc portion 71 and the second arc portion 72 are connected by a common tangent line, the first arc portion 71 and the second arc portion 72 are smoothly connected without unevenness. Therefore, the concentration of strain can be further alleviated, and the occurrence of cracks can be suppressed more stably.
In addition, by setting the radius of curvature R2 of the second arc portion 72 to 6 mm or more, the concentration of distortion in the second arc portion 72 can be alleviated, and the scallops can be easily cut and formed with a cutter. can be done.

Furthermore, the end connection structure 200 of the welded assembly H-section beam 1 has the first opening edge 61 having the first opening end 60a and the flange 20 having the first opening end 60a, as in the third embodiment. A linear portion 75 may be provided parallel to the inner surface 21, and one end 71a of the first arc portion 71 may be connected to the linear portion 75, thereby welding the axial end 20a of the flange 20. A sufficient space for welding can be secured, and the welding between the flange 20 and the column 110 can be stably performed, and welding defects can be prevented from occurring.

Further, according to the weld assembled H-section beam 1 according to the third aspect and the fourth aspect, the width W of the non-welding portion 30a between the pair of connecting portions 30, 30 is 0.94 of the thickness of the web. The first open ends 60a of the scallops 60B and 60C are located on the surface of the connecting portion 30 and the web 10 at a position closer to the web 10 side than the inner surface of the lower flange 20, and the scallop bottom is the inner surface of the lower flange 20. , the non-welding portion 30a can be prevented from being exposed to the scalloped bottom. Furthermore, since the web side toe portion 31 of the connecting portion 30 and the scalloped bottom are close to each other, the shear strain of the web toe portion 31 of the connecting portion 30 can be increased, and the web toe portion 31 of the connecting portion 30 can be stretched along the web side toe portion 31 . Cracks can be generated and propagated. Therefore, it is possible to prevent cracks from occurring and propagating from the tip of the unwelded portion during an earthquake.

In order to demonstrate the effect of the present invention, numerical analysis was performed on a specific example of the beam end joint 100 as in the above embodiment.
The finite element method was used as an analysis method, and ANSYS. Ver16 was used. FIG. 8 shows the entire model of the beam end joint 100, which is an analysis model for analysis in this embodiment. As shown in FIG. 8, the analysis model is a cantilever beam type, and the width direction of the beam 1 is 1/2 in consideration of symmetry. The analytical model was created with three-dimensional solid elements using 8-node hexahedral elements. The material properties of the steel materials used for the column 110 and the beam 1 are the same material and the same material properties for both the column 110 and the beam 1, and the stress-strain curve obtained from the SN490B material test results was modeled with multiple linear components. used things.
The cross section of the _{welded assembled} H-shaped cross-section beam used as the beam 1 is as shown in _FIG . used things. Here, the cross-sectional shape of the connecting portion 30 (the shape of the portion excluding the cross sections of the original web and flange from the weld metal portion) is the leg length s in the height direction from the inner surface 21 of the flange 20 to the web toe portion 31 It is an isosceles triangle in which _w and the horizontal leg length s _f from the web surface 11 of the web 10 to the flange toe 32 are equal, and s _w =s _f =18 mm. Also, the length _Lb from the side surface of the column 110 to the end of the beam 1 in the axial direction was set to 3500 mm. The thickness t _d (see FIG. 2) of the diaphragm 112 on the column 110 side to which the shaft end 20a of the flange 20 is welded was 32 mm. Although not shown, the column 110 had an outer diameter Bc of 500 mm and a plate thickness _tcf of 16 mm.

For the analysis, 53 types of models were analyzed by changing parameters relating to the shape of the scallop 60 . The shape of the scallop 60 used as an analysis model includes those shown in FIGS. The second opening edge portion 62 is composed only of the second linear portion 74, and the first circular arc portion 71 and the second circular arc portion 72 are continuously connected by a common tangent line. Parameters related to the shape of the scallop 60 include the radius of curvature R1 (mm) of the first arc portion 71, the radius of curvature R2 (mm) of the second arc portion 72, and the length of the first straight portion 73 (75). a height L, a scallop separation distance S _rf (mm), and a height dimension S _rh of the scallops 60 . Arc portion termination height Hc, which is the height from the inner surface 21 of the flange 20 of the other end _71b of the first arc portion 71 on the side away from the shaft end portion 1a, is the radius of curvature R1 of the first arc portion 71. (mm), the radius of curvature R2 (mm) of the second circular arc portion 72, the scallop separation distance _{Srf, and the height dimension Srh of} the scallop 60. As shown in FIG. Tables 1 and 2 show the parameter values of each analysis model.

As shown in Tables 1 and 2, NO. In 1 to 25, while changing the above parameters, the curvature radius R1 of the first arc portion 71 is made larger than 1.0 times the curvature radius R2 of the second arc portion 72, and the first arc portion 71 is The web toe portion 31 intersects, that is, the arc portion terminal height Hc is set to be _equal to or greater than the leg length _sw in the height direction.
On the other hand, NO. In 26 to 39, while changing the above parameters, the curvature radius R1 of the first arc portion 71 is made larger than 1.0 times the curvature radius R2 of the second arc portion 72, and the arc portion end height H _c is less than the leg length _sw in the height direction.
Also, NO. In 40 to 44, while changing the above parameters, the radius of curvature R1 of the first arc portion 71 is set to be less than 1.0 times the radius of curvature R2 of the second arc portion 72, and the arc portion end height H _c is greater than or equal to the height _sw .
Furthermore, NO. In 45 to 53, while changing the above parameters, the radius of curvature R1 of the first arc portion 71 is set to be less than 1.0 times the radius of curvature R2 of the second arc portion 72, and the arc portion end height H _c is less than the leg length _sw in the height direction.

A load was applied to the ends of the beam 1 in the axial direction to deform the beam 1 in these analytical models. Then, as shown in FIG. 9, the rotation angle θ at the loading point of the beam 1 (the angle formed by the axis _Lb0 of the beam 1 before deformation and the axis Lb1 of the beam 1 after deformation is calculated from the angle formed by the axis _Lb1 of the beam 1 at the beam end joint). The rotation angle component φ of the side surface 111a of the beam 1 (the angle formed by the axis _Lc0 of the side surface 111a of the column 110 before deformation and the axis _Lc1 of the side surface 111a of the column 110 after deformation) is subtracted from The rotation angle when the entire cross section of the shaft end portion 1a is plasticized is _θp , and the beam 1 is deformed until the angle becomes 3· _θp , which is three times this angle. Then, the equivalent plastic strain distribution and the plastic shear strain distribution at θ=3·θ _p were determined by the finite element method. As an example, NO. 12 equivalent plastic strain distributions are shown in FIG. 45 shows the equivalent plastic strain distribution. Also, as an example, NO. 12 plastic shear strain distributions are shown in FIG. 24 shows the plastic shear strain distribution of 24. Further, the maximum equivalent plastic strain εmax (%) at the scallop bottom of the scallop 60 was obtained based on the analysis results by the finite element method. Tables 1 and 2 show the maximum equivalent plastic strain εmax in each analysis model. FIG. 14 shows a graph plotting the relationship between the ratio R1/R2 of the curvature radius R1 of the first arc portion 71 to the curvature radius R2 of the second arc portion 72 and the corresponding maximum equivalent plastic strain εmax. The triangular plots in the figure indicate NO. 45 results, the other plots are no. Analysis results other than 45 are shown. A dotted line P1 parallel to the horizontal axis indicates εmax=20%, and a dotted line Q1 parallel to the vertical axis indicates the ratio R1/R2=1.0.

From Tables 1 and 2 and FIG. 14, it can be seen that the maximum equivalent plastic strain εmax tends to decrease as the ratio R1/R2 of the radius of the first arc portion 71 to the radius of the second arc portion 72 increases. I understand. In particular, in analysis cases where R1/R2 exceeds 1.0, εmax stays at a low value of about 20% or less regardless of the numerical values of individual analysis parameters. That is, when R1/R2 exceeds 1.0, strain concentration on the scalloped bottom is relaxed compared to when R1/R2 is 1.0 or less. In addition, it is desirable to increase R1/R2 in order to more stably alleviate the concentration of strain on the scallop bottom. 0.5 or more is desirable. As shown in FIG. 10, in the analysis model where R1/R2>1.0, for example, the analysis model NO. 12, the maximum equivalent plastic strain εmax at the scallop bottom is suppressed, and in particular, the equivalent plastic strain near the one end 71a where the tangent line is parallel to the inner surface 21 of the flange 20 in the first circular arc portion 71 can be suppressed. It is accepted that there are That is, by setting R1/R2>1.0, it is possible to suppress the occurrence of cracks in the vicinity of the intersection between the web 10 and the flange 20 . Therefore, by adopting a structure similar to that of an analysis model in which R1/R2>1.0, cracks are suppressed from being generated in the first circular arc portion 71 during a maximum earthquake, and cracks occur in the flange 20. Extension toward the outer surface 22 (see FIG. 3) can be suppressed. On the other hand, in the analysis model with the ratio R1/R2≦1.0, the analysis model NO. As shown in 45, the maximum equivalent plastic strain εmax at the scalloped bottom increases, and the equivalent plastic strain near the one end 71a where the tangent line is parallel to the inner surface 21 of the flange 20 in the first arc portion 71 can be suppressed. It is accepted that the
In this way, it is not possible to suppress the occurrence of cracks near the intersections of the web 10 and the flanges 20 . Therefore, in a structure such as the analysis model in which R1/R2 ≤ 1.0, a crack occurs in the first circular arc portion 71 at the time of a maximum earthquake, and the crack propagates toward the outer surface 22 of the flange 20. It is likely to progress. When the crack propagates toward the outer surface 22 of the flange 20, the high tensile stress acting on the flange 20 promotes brittle fracture of the flange.

Further, in the analysis model satisfying H _c ≧s _w , the analysis model No. shown in FIG. As shown in 12, the distribution of plastic shear strain along the vicinity of the web toe 31 in the connecting portion 30 is widely formed in the axial direction of the beam 1, and the strain value is also high. That is, in the shape of the scallop 60 in which the first arc portion 71 intersects the web toe portion 31 because of H _c ≧s _w , the ductile crack occurs in the vicinity of the web toe portion 31 and the generated crack can be stably extended axially along the web toe portion 31 of the connecting portion 30 having an H-shaped cross section and a relatively small thickness in the width direction. That is, it is possible to suppress rupture due to cracks directed toward the outer surface 22 of the flange 20, and furthermore, clarify the location where the crack occurs, making it easy to visually recognize the crack after a large earthquake, and repair it quickly. It is also possible to do it easily. On the other hand, the _analytical model _NO . 24, as shown in FIG. 13, the first arc portion 71 does not intersect the web toe portion 31 of the connecting portion 30, and the second arc portion 72 is also included in the connecting portion 30. A distribution of plastic shear strain along the axial direction of is not formed. Therefore, cracks occur at the first arc portion 71 . Since this crack propagates inside the connecting portion 30, it is difficult to detect the occurrence of the crack, and the crack propagates toward the outer surface 22 of the flange 20, thereby promoting brittle fracture of the flange.

As described above, in order to alleviate the strain concentration at the scallop bottom, (1) the radius of curvature R1 of the first arc portion 71 on the flange side should be larger than the radius of curvature R2 of the second arc portion 72, and (2) It is important that the web toe 31 of the submerged arc weld (connection 30) and the first arc 71 of the scallops 60, 60A, 60B, 60C intersect and shear deformation at the intersection is dominant. . The distance from the inner surface 21 of the flange 20 to the web toe 31 at the connection 30 is determined by intersecting the web toe 31 of the connection 30 with the first arc 71 of the scallops 60, 60A, 60B, 60C. is smaller than the total height of the height dimension _Srh of the _scallop 60 and the scallop separation distance _Srf .
In (1), for example, the radius of curvature R1 of the first arc portion 71 is 35 mm, and the radius of curvature R2 of the second arc portion 72 is 6 mm. The effects of the leg length _sw in the height direction of 30 and the non-welded portion 30a on the distortion of the scalloped bottom were numerically analyzed.

Analysis parameters are shown in Table 3. The parameters were the leg length sw in the height direction of the connecting portion 30 and the width _W of the unwelded portion. The beam (welded assembled H-section beam) was BH-700×200×16×22, and the column (steel pipe column) was □500×16.
In addition, among the specimens used in the full-scale experiments, the specimen was set based on a specimen of a thick-web beam with high distortion at the bottom of the scallop. For SW2, SW3, MW2, and MW3, the width of the unwelded portion exceeds the thickness of the web, but the analysis was performed as a reference.

Analysis Results FIG. 15 shows the analysis results of the S, SW1, M, MW1, and L specimens. The vertical axis indicates the maximum equivalent plastic strain (εmax (%)) at the position of the highest strain on the scalloped bottom, and the horizontal axis indicates the amount of deformation (mm) at the tip of the beam. The greater the value of the maximum equivalent plastic strain on the vertical axis, the higher the risk of scallop rupture.
As shown in FIG. 15, it is considered that the size of the leg length sw in the height direction has a greater effect on the equivalent plastic strain of the scalloped bottom than the width _W of the unwelded portion.

FIG. 16 shows analysis results of small leg length analysis models (S, SW1 to SW3 specimens), and FIG. 17 shows analysis results of medium leg length analysis models (M, MW1 to MW3). 16 and 17, the vertical axis indicates the maximum equivalent plastic strain (εmax (%)), and the horizontal axis indicates the deformation amount (mm) of the tip of the beam.
As shown in FIGS. 16 and 17, although it can be said that the size of the unwelded portion width W affects the equivalent plastic strain of the scalloped bottom, the unwelded portion width W falls within the web plate thickness range (within 16 mm). As long as the width W of the unwelded portion is 0, the difference in the maximum equivalent plastic strain from the test specimen is small, so the effect is considered to be small (see SW1 in FIG. 16 and NM1 in FIG. 17, respectively) ).

FIG. 18 shows the maximum equivalent plastic strain at the bottom of the scallops when the amount of deformation at the beam tip of the S, SW1 to SW3, M, and MW1 to MW3 specimens is 80 mm. Here, the vertical axis indicates the value obtained by dividing the maximum equivalent plastic strain value of each analysis model by the analysis model (S or M) with the same leg length size and the non-welded portion W of 0 mm, and the horizontal axis indicates the non-welded portion W of each analysis model. The value obtained by dividing the weld width W by the web thickness _tbw is shown.
As shown in FIG. 18, the equivalent plastic strain sharply increases with respect to the analysis model without the unwelded portion at MW1, where the width of the _unwelded portion is 0.94 times the thickness of the web (line Lw in FIG. 18). It can be confirmed that the Therefore, it is considered important to suppress the width of the unwelded portion to 0.94 times or less of the thickness of the web.

As described above, in the scalloped shape of the present invention, when the width of the unwelded portion is within 0.94 times the thickness of the web, the influence of the unwelded portion width W on the distortion of the scalloped bottom is very large. It can be said that it can be kept small. However, since the width of the unwelded portion and the distortion of the scalloped bottom are somewhat correlated, it is desirable to reduce the width of the unwelded portion.
Moreover, the leg length in the height direction of the connecting portion has a large effect on the distortion of the scalloped bottom. The reason for this is thought to be that when the leg length is large at the strain concentration point of the scalloped bottom (≈the size of the weld metal at the joint), the surrounding constraint increases.
In addition, in order to promote shear deformation at the weld toe of the connecting part and alleviate strain concentration at the scallop bottom, it is minimum to cross the first arc part of the scallop bottom and the weld toe of the connecting part. limited. It is also considered important to bring the apex of the remaining fillet and the weld toe of the joint as close as possible by keeping the leg length in the height direction of the joint low or increasing the distance between the scallops.
Thus, it is important to keep the leg length in the height direction of the connecting portion as low as possible. As long as the width of the unwelded portion is 0.94 times or less the thickness of the web, the width of the unwelded portion has little effect on the equivalent plastic strain of the scalloped bottom, but it is desirable to reduce the width of the unwelded portion.

As described above, the embodiments and examples of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to these embodiments and examples. etc. are also included.

1 beam (welded assembled H-shaped cross-section beam)
1a Shaft end 10 Web 20 Flange 30 Connecting portion 30a Non-welding portions 60, 60A, 60B, 60C Scallop 60a First opening end 60b Second opening end 61 First opening edge 62 Second opening edge 63 Third opening edge portion 71 First arc portion 72 Second arc portion 73 First straight portion (straight portion)
R1 Curvature radius of the first circular arc portion R2 Curvature radius of the second circular arc portion S _Rh Scallop height dimension 100 Beam end joint 110 Column (welded assembly H-shaped cross-section beam)
End connection structure of 200 H-section beam

Claims (7)

A welded assembled H-section beam comprising a web, a pair of upper and lower flanges provided at both ends of the web in the web width direction, and a connecting portion for joining the web and the pair of upper and lower flanges by welding, ,
A scallop is provided at an end of the web in the web width direction,
The scallops are
a first open end located on the lower flange side of the pair of upper and lower flanges;
a second open end located on a side opposite to the first open end;
a first open edge extending from the first open end away from the end of the web;
a second open edge extending from the second open end and away from the end of the web;
a third opening edge connecting the first opening edge and the second opening edge;
The first opening edge is formed in an arc shape so as to intersect with a toe on the web side of the connecting portion provided at a portion where the web and the lower flange intersect. has a first arc portion at one end on the open end side of the lower flange, the tangent of which is parallel to the inner surface of the lower flange;
The third opening edge has a second circular arc portion formed in an arc shape connecting the first opening edge and the second opening edge,
The weld assembled H-section beam, wherein the radius of curvature of the first arc portion is greater than the radius of curvature of the second arc portion. A pair of the connecting portions are provided with the web sandwiched in the thickness direction thereof,
An unwelded portion is provided between the pair of connecting portions, the width of the unwelded portion is 0.94 times or less the thickness of the web plate, and the first open end of the scallop extends from the inner surface of the lower flange to the web. 2. A welded assembled H-section beam according to claim 1, on the surface of said joint and said web in a lateral position. The first arc portion and the second arc portion are connected at a portion where the arc formed by the first arc portion and the arc formed by the second arc portion are a common tangent line. A welded assembled H-section beam according to claim 1 or 2. The first opening edge includes the first opening end and has a linear portion arranged parallel to the inner surface of the nearest lower flange, and the first opening of the first arc portion. The welded assembled H-section beam according to any one of claims 1 to 3, wherein one end on the end side is connected to the straight portion. The weld assembly H-shaped cross section according to any one of claims 1 to 4, wherein the radius of curvature of the first arc portion is 2.5 times or more the radius of curvature of the second arc portion. beam. The weld assembled H-section beam according to any one of claims 1 to 5, wherein the dimension of the scallop in the direction from the lower flange side to the upper flange side is 15 mm or more. The welded assembled H-section beam according to any one of claims 1 to 6, wherein the radius of curvature of the second arc portion is 6 mm or more.

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