Beam members, column-beam joint structures, and methods for controlling the performance of welded joints in beam members.

Abstract

In the joint structure formed between beam members and column members, the size of the column members transported to the construction site is reduced. [Solution] A beam member is provided, comprising a web and a pair of flanges, wherein the web comprises a first web in a first section including the longitudinal end of the beam member and a second web in a second longitudinal section, and a first web weld is formed between the first web and the second web; each of the pair of flanges comprises a first flange in the first section and a second flange in the second section, and a first flange weld is formed between the first flange and the second flange; a scallop is formed on the first web or the second web at the boundary between the first section and the second section; and the first flange weld is formed using a backing plate extending through the scallop.

Description

[Technical Field]

[0001] The present invention relates to a beam member, a column-beam joint structure, and a method for managing the performance of welded joints in a beam member. [Background technology]

[0002] In joint structures formed between beam members and column members, it is common practice to pre-attach brackets having the same cross-section as the beam member to the column member at a factory or similar facility, and then join the brackets to the beam member at the construction site using high-strength bolts or the like. Examples of such techniques are described, for example, in Patent Documents 1 and 2. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2015-098720 [Patent Document 2] Japanese Patent Publication No. 2016-160581 [Overview of the project] [Problems that the invention aims to solve]

[0004] The bracket-based joint structure described above has advantages such as being able to widen the flange at the bracket portion or making the plate thickness of the bracket portion different from that of the beam member, as described in Patent Documents 1 and 2, for example. On the other hand, the size of the column member increases due to the addition of the bracket, which can make transportation difficult.

[0005] Therefore, the present invention aims to provide a beam member, a column-beam joint structure, and a method for managing the performance of welded joints in a beam member, which can reduce the size of the column member that is brought to the construction site in a joint structure formed between a beam member and a column member. [Means for solving the problem]

[0006] [1]A beam member including a web and a pair of flanges, wherein the web includes a first web in a first section including the longitudinal ends of the beam member and a second web in a second longitudinal section, a first web weld is formed between the first web and the second web, each of the pair of flanges includes a first flange in the first section and a second flange in the second section, a first flange weld is formed between the first flange and the second flange, a scallop is formed in the first web or the second web at the boundary between the first section and the second section, and the first flange weld is formed using a backing plate extending through the scallop. [2]The beam member according to [1], wherein the backing plate abuts against a side end of the first web weld across the scallop in the height direction of the beam member. [3]The beam member according to [1], wherein the width of the first flange widens toward the longitudinal ends of the beam member. [4]The beam member according to [1], wherein the width of the first flange is wider than the width of the second flange. [5]The beam member according to [1], wherein the plate thickness of the first flange is thicker than the plate thickness of the second flange. [6]The beam member according to [1], wherein the portion including the first web and the first flange is a fabricated H-shaped steel, and the portion including the second web and the second flange is a rolled H-shaped steel. [7]The beam member according to [1], wherein the portion including the first web and the first flange and the portion including the second web and the second flange are rolled H-shaped steels. [8]A column-beam joint structure including the beam member according to any one of [1] to [7] and a column member, wherein the ends of the first web and the first flange are joined to the column member. A method for managing the performance of a welded joint in a beam member as described in any one of items [9], [1] to [7], wherein the length of the first section is longer than either 1 / 10 the length of the beam member or the beam depth, and the Charpy absorption energy of the first flange weld is 27 J or more. A method for managing the performance of a welded joint in a beam member as described in any one of items [1] to [7], wherein the length of the first section is 1 / 10 times or less the length of the beam member or less than or equal to the beam depth, and the Charpy absorption energy of the first flange weld is 70 J or more. [Effects of the Invention]

[0007] According to the above configuration, the beam member is divided into a section including the end and an intermediate section, and the divided sections are joined together in advance by welding, for example, in a factory. This makes it easy to widen the flange, increase the plate thickness, or use different types of steel in the section including the end of the beam member, without using brackets. Since brackets do not need to be attached to the column member in advance, the size of the column member to be transported to the construction site can be reduced. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic perspective view of a beam member according to one embodiment of the present invention. [Figure 2] This figure shows a column-beam joint structure including the beam member shown in Figure 1. [Figure 3] This diagram illustrates a method for cutting a flange with varying width from a steel plate. [Figure 4] This diagram illustrates a method for cutting a flange with varying width from a steel plate. [Figure 5] A perspective view showing a part of a beam member according to another embodiment of the present invention. [Figure 6] A perspective view showing a part of a beam member according to another embodiment of the present invention. [Figure 7]This figure shows an example of the configuration of the welded joints of the web and flange in the beam member shown in Figure 1. [Figure 8] This figure shows another example of the configuration of the web and flange welds in the beam member shown in Figure 1. [Figure 9] This is a diagram illustrating the dimensions of the backing plate and scallops. [Figure 10] This figure shows an example where the scallop height is minimized in the configuration shown in Figure 8. [Figure 11] This figure shows an example where the height of the backing plate has been increased in the configuration shown in Figure 8. [Figure 12] This figure shows an example where the height of the backing plate is increased only in the center, and decreased on the end faces, in the configuration shown in Figure 8. [Figure 13] This diagram shows the sample sampling locations for the Charpy impact test on the groove side. [Figure 14] This diagram shows the specimen sampling locations for the Charpy impact test on the dorsal side of the groove. [Modes for carrying out the invention]

[0009] Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings. In this specification and drawings, components having substantially the same functional configuration are denoted by the same reference numerals, and redundant descriptions will be omitted.

[0010] Figure 1 is a schematic perspective view of a beam member according to one embodiment of the present invention. The beam member 10 is an H-shaped cross section beam including a web 11 and a pair of flanges, specifically an upper flange 12 and a lower flange 13. The beam member 10 is divided into a first section S1, a second section S2, and a third section S3 in the longitudinal direction of the beam member 10, and each section is joined by welding. The first section S1 is the section including one end of the beam member 10 in the longitudinal direction, the third section S3 is the section including the other end of the beam member 10 in the longitudinal direction, and the second section S2 is the section in between them.

[0011] More specifically, the web 11 includes web 11A in the first section S1, web 11B in the second section S2, and web 11C in the third section S3, with a web weld 21A formed between web 11A and web 11B, and a web weld 21B formed between web 11B and web 11C. The upper flange 12 also includes upper flange 12A in the first section S1, upper flange 12B in the second section S2, and upper flange 12C in the third section S3, with an upper flange weld 22A formed between upper flange 12A and upper flange 12B, and an upper flange weld 22B formed between upper flange 12B and upper flange 12C. Similarly, the lower flange 13 includes the lower flange 13A in the first section S1, the lower flange 13B in the second section S2, and the lower flange 13C in the third section S3, with a lower flange weld 23A formed between the lower flange 13A and the lower flange 13B, and a lower flange weld 23B formed between the lower flange 13B and the lower flange 13C.

[0012] Of the welds formed on the web and flange between the first section S1 and the second section S2 of the beam member 10, and between the second section S2 and the third section S3, the upper flange welds 22A, 22B formed on the upper flange 12 and the lower flange welds 23A, 23B formed on the lower flange 13 are full penetration welds formed using backing plates 32A, 32B, 33A, 33B. As will be described later, the backing plates 32A, 32B, 33A, 33B extend through the scallops formed on the web 11 at the boundary between the first section S1 and the second section S2, and at the boundary between the second section S2 and the third section S3, and are arranged over almost the entire width of the upper flange 12 and the lower flange 13. Therefore, the upper flange welds 22A, 22B and the lower flange welds 23A, 23B are also formed over almost the entire width of the upper flange 12 and the lower flange 13. With this configuration, the beam member 10 can adequately transmit the stress between the first section S1 and the third section S3 at the end and the intermediate section S2.

[0013] Also, in the illustrated example, in the first section S1 and the third section S3, the widths of the upper flange 12 and the lower flange 13 become wider toward the ends of the beam member 10. More specifically, the first section S1 includes a section S 32 ,

[0014] , , 33 , 31 , where the width B 11 of the upper flange 12A and the lower flange 13A is wide on the one end side of the beam member 10, a section S 12 where the width B 12 of the upper flange 12A and the lower flange 13A is narrow on the intermediate part side, and a section S 13 where the widths of the upper flange 12A and the lower flange 13A change therebetween. Similarly, the third section S3 includes a section S 31 where the width B 31 of the upper flange 12C and the lower flange 13C is wide on the other end side of the beam member 10, a section S 32 where the width B 32 of the upper flange 12C and the lower flange 13C is narrow on the intermediate part side, and a section S 33 where the widths of the upper flange 12C and the lower flange 13C change therebetween. Here, the length of the section S 31 or the section S 32 may be 0 mm without any problem.

[0014] Figure 2 shows a column-beam joint structure including the beam member shown in Figure 1. In the joint structure 100, one end of the beam member 10 is joined to the column member 40. More specifically, the column member 40 includes square steel pipe columns 41A, 41B, 41C, and diaphragms 42A, 42B interposed between them. The ends of the upper flange 12 and lower flange 13 of the beam member 10 are joined to the diaphragms 42A, 42B by welds 43A, 43B, respectively, and the end of the web 11 is bolted to a gusset plate 44 welded to the side of the square steel pipe column 41B. Note that the bolts are not shown in the illustration. As described above, the width of the upper flange 12 and lower flange 13 is wider at the end of the beam member 10, so that the welds 43A, 43B between the beam member 10 and the column member 40 are less likely to deform plastically during an earthquake, and failure at the welds 43A, 43B is suppressed, thereby improving the seismic performance of the joint structure 100. On the other hand, in the middle section of the beam member 10, which does not affect the seismic performance of the joint structure, the width of the upper flange 12 and the lower flange 13 is narrowed, thus reducing the overall steel weight of the beam member 10.

[0015] The joining structure is not limited to the example shown in Figure 2, and various configurations are possible. The column members are not limited to square steel pipe columns; for example, they may be welded box-section columns. For example, when using an internal diaphragm or core member, the upper and lower flanges of the beam member may be welded to the sides of the column or core member. The beam members do not necessarily have to be joined to the column from four directions as in the example in Figure 2; they may be joined from one, two, or three directions. Also, the web and column members may be joined by welding instead of bolts.

[0016] Figures 3 and 4 illustrate a method for cutting flanges with varying widths from a steel plate. Figure 3 shows the method for cutting the flanges of a beam member from a steel plate in the example shown in Figure 1, while Figure 4 shows a method that differs from the example in Figure 1, where the flanges are not formed and welded in sections along the longitudinal direction, but rather cut from a steel plate with the flanges integrally formed over the entire length of the beam member. In the example in Figure 1, for the upper flange 12A and lower flange 13A in the first section S1, and the upper flange 12C and lower flange 13C in the third section S3, the wide and narrow sections of the flanges are of roughly equal length. Therefore, as shown in Figure 3, by arranging multiple flanges so that the wide and narrow sections alternate, the flanges can be cut from the steel plate without waste. On the other hand, when the flanges are integrally formed over the entire length of the beam member, as shown in Figure 4, the narrow section of the flange is longer than the wide section, resulting in processing loss P when cutting multiple flanges from a steel plate. L This happens frequently.

[0017] As described above, in one embodiment of the present invention, the entire beam member 10, including the web 11, upper flange 12, and lower flange 13, is divided between a first section S1 including one end of the beam member 10, an intermediate second section S2, and a third section S3 including the other end, and the divided parts are joined together by welding. This makes it possible to cut the flanges from the steel plate without waste when, for example, as described with reference to Figures 3 and 4, the width of the upper flange 12 and lower flange 13 at the end of the beam member 10 is widened to improve the seismic performance of the joint structure 100.

[0018] Furthermore, the embodiments of the present invention are not limited to cases where the flange width changes at the end of the beam member, as illustrated in Figure 1. For example, in other embodiments, the flange width changes in the section S shown in Figure 1. 13 ,S 33 This continues to the end of the beam member, and the flange width is wide in section S. 11 ,S 31It is not necessary for it to exist. Also, as shown in the example in Figure 5, the flange width B1 may be wider than the flange width B2 in the intermediate section over the entire section including the end of the beam member (B1>B2). Alternatively, as shown in the example in Figure 6, the flange thickness t1 in the section including the end of the beam member may be thicker than the flange thickness t2 in the intermediate section (t1>t2). The configurations in which the flange width is wider, as illustrated in Figures 1 and 5, and the example in which the flange thickness is thicker, as illustrated in Figure 6, can be combined. In the illustrated examples, the web thickness does not change, but the web thickness may also be thicker in the section including the end of the beam member. Even if the cross-sectional shape is the same between the section including the end of the beam member and the intermediate section, the materials of the steel constituting the flange and web may be different.

[0019] Furthermore, the beam member according to the embodiment of the present invention is not limited to assembled H-shaped steel in which the flange and web are joined by welding, but may also be rolled H-shaped steel in which the flange and web are integrally formed by rolling. For example, the portion of the first section S1 including the web 11A and flanges 12A, 13A, and the portion of the third section S3 including the web 11C and flanges 12C, 13C may be assembled H-shaped steel, and the portion of the second section S2 including the web 11B and flanges 12B, 13B may be rolled H-shaped steel. Alternatively, if the plate thickness of the flange and web, or the material of the steel constituting them, differs between the sections S1, S3 including the ends of the beam member and the intermediate section S2, the first section S1, the second section S2, and the third section S3 may all be rolled H-shaped steel. Alternatively, the first section S1 and the second section S2 may be rolled H-shaped steel, and the third section S3 may be assembled H-shaped steel. For example, as shown in the example in Figure 1, if the width of the first section S1 changes within the section and the first section S1 is made of rolled H-beam steel, a wing plate may be attached to the side of the flange to create a wider section, or a narrower section may be formed by cutting a part of the wider flange.

[0020] As described above, a configuration similar to dividing the beam member into a section including the end and an intermediate section can also be achieved by pre-attaching the section including the end to the column member as a bracket in a factory or elsewhere, and then joining the bracket to the beam member corresponding to the intermediate section at the construction site. However, as already mentioned, in that case the size of the column member becomes larger, making it difficult to transport. In the embodiment of the present invention, by pre-attaching the divided parts of the beam member by welding, for example, in a factory or elsewhere, it is possible to reduce the size of the column member that is brought to the construction site, while adopting configurations such as widening the flange at the end of the beam member or increasing the plate thickness.

[0021] Figure 7 shows an example of the configuration of the welds on the web and flanges of the beam member shown in Figure 1. Referring to Figure 7, the configuration of the welds and their surroundings formed on the web and flanges between the first section S1 and the second section S2 of the beam member 10 will be further explained. The same applies between the second section S2 and the third section S3. Between the first section S1 and the second section S2, an upper flange weld 22A is formed on the upper flange 12, and a lower flange weld 23A is formed on the lower flange 13. On the web 11B on the second section S2 side, scallops 14A and 14B are formed in contact with the upper flange 12B and the lower flange 13B to allow the backing plates 32A and 33A to pass through. As already mentioned, by having the backing plates 32A and 32B extend through the scallops 14A and 14B, a full penetration weld using the backing plates 32A and 33A can be formed over almost the entire width of the upper flange 12 and the lower flange 13. Because not only the upper flange 12 and the lower flange 13 but also the web 11 is divided between the first section S1 and the second section S2, beveling and scalloping only need to be performed on either the first section S1 or the second section S2, making it easier to process scallops 14A and 14B as described above. The scallop may be formed on the web 11A on the first section S1 side, but if, for example, the web 11A on the end side of the beam member 10 has a thicker plate, it is easier to form it on the web 11B on the second section S2 side.

[0022] Meanwhile, a web weld 21A is formed on the web 11 between the first section S1 and the second section S2. The configuration of the web weld 21A is not particularly limited, and welding using a backing plate (not shown) may be used. End tabs 15A and 15B are placed at the side ends of the web weld 21A to hold the side ends of the bead during welding. When flux tabs are used for the end tabs 15A and 15B, they are removed after welding as shown in the illustrated example, but when steel end tabs are used for the end tabs 15A and 15B, they may be removed by cutting or other means after welding, or they may be left in place. In addition, although not shown in Figures 1 and 7, end tabs may also be placed at the side ends of the upper flange weld 22A and the lower flange weld 23A.

[0023] Figure 8 shows another example of the configuration of the web and flange welds in the beam member shown in Figure 1. In the weld configuration shown in Figure 8, the backing plates 32A and 33A for forming the welds 22A and 23A of the upper flange 12 and lower flange 13 also function as end tabs positioned at the side ends of the web weld 21A. In this case, the backing plates 32A and 33A traverse the scallops 14A and 14B in the height direction of the beam member 10, i.e., in the width direction of the web 11, and abut against the side ends of the web weld 21A. In this case, the dimensions of the backing plates 32A and 33A in the height direction of the beam member 10 are approximately equal to the dimensions of the scallops 14A and 14B. The backing plates 32A and 33A of the flange welds 22A and 23A also function as end tabs for the web weld 21A, resulting in fewer parts and simplified construction. The rest of the configuration is the same as that of the example in Figure 7. A similar configuration can be applied between the second section S2 and the third section S3. Furthermore, the height dimensions of the backing plates 32A and 33A do not necessarily have to be constant in the width direction; for example, as shown in the example described later, backing plates with a higher height can be used only around the area directly below the beam web.

[0024] Below, we will further explain an example of how to construct the backing plate and scallop, as shown in Figure 8. Figure 9 is a diagram illustrating the dimensions of the backing plate and scallop. In Figure 9, the backing plate center height H is shown as the dimension of the backing plate and scallop in the beam member height direction, i.e., in the web width direction. B and scallop height H S This is shown. Also, Figure 9 shows the length L of the backing plate as the longitudinal dimension of the beam member for the backing plate and scallop. B , Scalloped bottom length L S1 and scallop top length L S2 This is shown. Here, the bottom of the scallop is the part where the scallop is in contact with the flange, and the top of the scallop is the opposite side of the bottom where the scallop shape is parallel to the flange. Figure 9 also shows the root gap length RG of the groove formed in the flange.

[0025] As mentioned above, in the example in Figure 8, the scallop height H S and backing metal center height H B (H S ≒H B To achieve this, it is possible to either minimize the scallop height or increase the central height of the backing plate to match the scallop height, compared to the dimensions of a normal scallop and backing plate as shown in the example in Figure 7. Examples of each will be explained below with reference to Figures 10 and 11. Although the backing plate 33A and scallop 14B between the lower flanges 13A and 13B are shown as examples, the same applies to other welds. Also, in Figures 9, 10, 11 and 12, the illustration of the weld metal of the weld is omitted, and the state before welding is shown.

[0026] Figure 10 shows an example in which the scallop height is minimized to match the backing plate, using a backing plate with a constant height in the width direction, as in the configuration of Figure 8. In this example, for example, the size of backing plate 33A is a typical H B ×L B If the dimensions are 9mm x 25mm, then the height of the scallop 14B is H S Approximately 9mm, scalloped bottom length LS1 and scallop top length L S2 All of these will be 25mm or longer. Scallop length L S1 ,L S2 There is no particular upper limit, but the deeper the scallop, the more likely the flange 13B is to bend, so the scallop length L S1 ,L S2 It is desirable to keep the flange width or less.

[0027] Figure 11 shows an example where, using the configuration of Figure 8, the height of the backing plate is constant in the width direction, but the height of the backing plate is increased to match the scallop height. In this example, for example, the scallop height H S If the standard is 35mm, then the center height of the backing plate H B This will be approximately 35mm. On the other hand, the length of the backing plate L B The root gap length is greater than or equal to RG, and the typical bottom length is L. S1 In the case of a scallop with a longer shape, the scallop top length L S2 The following applies: Top length L S2 In the case of a scalloped edge with a longer shape, the length of the backing metal L B The scalloped bottom length is L S1 The following applies:

[0028] Figure 12 shows an example of the configuration in Figure 8, where the height of the backing plate is increased only in the center and decreased on the end faces. In this example, a portion of the rolled H-beam (flange and part of the web) is cut out and used as the backing plate 33A. For example, scallop height H S If the standard is 35mm, the height of the center of the backing plate H B The height is approximately 35mm. The height H is at the end face of the backing plate. BE is H B A smaller size is preferable, for example, 9mm or more, which is the typical height of a backing plate. The width W of the center of the backing plate. BCThis is greater than or equal to the thickness of the web of the beveled and scalloped beam (if beveling and scalloping is done in section S2 as in the example in Figure 8, the thickness of the web 11B; if beveling and scalloping is done in section S1 in other examples, the thickness of the web 11A). The bottom length L as illustrated in Figure 9. S1 In the case of a typical scallop with a longer shape, the length of the backing metal L B The length of the scalloped top is L. S2 The following applies: Top length L S2 In the case of a scalloped edge with a longer shape, the length of the backing metal L B The scalloped bottom length is L S1 The following applies:

[0029] Any of the examples in Figures 10, 11, and 12 above may be used. In the example in Figure 10, a general backing plate can be used, but a special processing machine may be required because the scallop is smaller than usual. In the examples in Figures 11 and 12, a backing plate of special dimensions is required, but the scallop size is the same as usual, so an existing beveling machine can be used, for example.

[0030] Next, an example of a method for managing the performance of welded joints in a beam member according to an embodiment of the present invention will be further described. In a beam member constituting a column-beam joint structure, if the length of the beam member is L and the beam depth is H, plastic deformation of the beam member is predicted during an earthquake in the range where the distance from the end of the beam member is L / 10 or less, or H or less. Therefore, if the length of the section including the end of the beam member (the first section S1 and the third section S3 in the above example) is longer than either L / 10 or H, the welded joint between these sections and the intermediate section (the second section S2 in the above example) is outside the range where plastic deformation is predicted during an earthquake. In this case, the Charpy absorption energy, which indicates the toughness of the welded joint, should be within a range that can withstand deformation in the elastic range, for example, 27 J or more. On the other hand, if the length of the section including the end of the beam member is L / 10 or less, or H or less, the welded joints of the flange and web are within the range where plastic deformation is predicted during an earthquake. In this case, it is desirable that the Charpy absorption energy, which indicates the toughness of the welded joint, be within a range that can withstand deformation in the plastic range, for example, 70 J or more. Furthermore, as the beam length L increases relative to the beam depth H, the range of plastic deformation during an earthquake becomes relatively longer relative to the beam depth H. Therefore, if necessary, the Charpy absorption energy may be set to 70 J or more even when the length of the section including the end of the beam member is 2 H or less.

[0031] The Charpy impact energy of the weld, as described above, is measured, for example, in a welding test conducted before the manufacture of the beam member. In the welding test, a Charpy impact test is performed in accordance with JIS Z2242 using a test material that simulates the joint of the beam member. The test piece for the Charpy impact test shall be taken from at least one of the groove side shown in Figure 13 and the groove back side shown in Figure 14. The Charpy impact energy, which indicates the toughness of the weld, is the average value of the test results at each of the three notch positions of the test piece: the weld fusion line (BOND), a position at least 1 mm away from the weld fusion line towards the base metal (HAZ), and a position at least 1 mm away from the weld fusion line towards the weld metal (DEPO). The larger the Charpy impact energy, the higher the toughness of the weld. For example, by selecting the shape and material of the weld so that the above conditions are met, and by managing the welding quality at the factory and on site, sufficient performance can be ensured for beam members that constitute a column-beam joint structure. [Explanation of Symbols]

[0032] 10...Beam member, 11,11A,11B,11C...Web, 12,12A,12B,12C...Upper flange, 13,13A,13B,13C...Lower flange, 14A,14B...Scallop, 15A,15B...End tab, 21A,21B...Web weld, 22A,22B...Upper flange weld, 23A,23B...Lower flange weld, 32A,32B,33A,33B...Backing plate, 40...Column member, 41A,41B,41C...Square steel pipe column, 42A,42B...Diaphragm, 43A,43B...Weld, 44...Gusset plate, 100...Joint structure, S1...First section, S2...Second section, S3...Third section.

Claims

1. A beam member including a web and a pair of flanges, The web includes a first web in a first section including the longitudinal end of the beam member and a second web in a second section in the longitudinal direction, and a first web weld is formed between the first web and the second web. Each of the pair of flanges includes a first flange in the first section and a second flange in the second section, and a first flange weld is formed between the first flange and the second flange. A scallop is formed on the first web or the second web at the boundary between the first section and the second section. The first flange weld is formed using a backing plate that extends through the scallop, and is a beam member.

2. The beam member according to claim 1, wherein the backing plate crosses the scallop in the height direction of the beam member and abuts against the side end of the first web weld.

3. The beam member according to claim 1, wherein the width of the first flange widens toward the longitudinal end of the beam member.

4. The beam member according to claim 1, wherein the width of the first flange is wider than the width of the second flange.

5. The beam member according to claim 1, wherein the thickness of the first flange is greater than the thickness of the second flange.

6. The portion including the first web and the first flange is an assembled H-beam, The beam member according to claim 1, wherein the portion including the second web and the second flange is made of rolled H-shaped steel.

7. The beam member according to claim 1, wherein the portion including the first web and the first flange, and the portion including the second web and the second flange, are made of rolled H-shaped steel.

8. A column-beam joint structure comprising a beam member and a column member according to any one of claims 1 to 7, A column-beam joint structure in which the ends of the first web and the first flange are joined to the column member.

9. A method for controlling the performance of a welded joint in a beam member according to any one of claims 1 to 7, The length of the first section is longer than either 1 / 10 the length of the beam member or the depth of the beam. A method for controlling the performance of a welded joint in a beam member, wherein the Charpy absorption energy of the first flange welded joint is 27 J or more.

10. A method for controlling the performance of a welded joint in a beam member according to any one of claims 1 to 7, The length of the first section is 1 / 10 times or less the length of the beam member or less than or equal to the beam depth. A method for controlling the performance of a welded joint in a beam member, wherein the Charpy absorption energy of the first flange welded joint is 70 J or more.

Images