Welded assembly box-sectioned column and method of manufacturing the same

Abstract

To provide a welded assembly box-sectioned column and a method of manufacturing the same.SOLUTION: The present invention relates to a welded assembly box-sectioned column that has column skin plates as four surfaces and one or more diaphragms, and also has, at a position where peripheral parts of the diaphragms adjoin to internal surfaces of the column skin plates, a backing strip arranged holding the peripheral parts of the diaphragms from both thickness-directional sides. The welded assembly box-sectioned column has: an electroslag weld metal part at a position surrounded with the inner surfaces of the column skin plates, the peripheral parts of the diaphragms, and the backing strip; a first fillet weld part between the column skin plates and the backing strip on three circumferential surfaces; a second fillet weld part between the backing strip and the peripheral parts of the diaphragms; and a first fillet weld part between the column skin plates and the backing strip on one circumferential surface, the column width-directional length of each fillet weld part being equal to or larger than the width of a beam for column joining.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a welded box section column and a manufacturing method thereof. [Background technology]

[0002] Generally, a box column (column with a box-shaped cross section) used in building structures has multiple diaphragms 101 inside the box column 100 for the purpose of transmitting stress from the beam flange to the column skin plate, as shown in Fig. 19. The box column 100 is assembled by arranging four column skin plates 102 with their long sides facing each other and corner-welding adjacent long sides together using submerged arc welding or the like. The diaphragm 101 is joined at its four peripheral sides to the column skin plate 102 by electroslag welding.

[0003] Figure 20 shows the cross-sectional structure of a typical electroslag-welded metal part in the box column 100 shown in Figure 19. A diaphragm 101 is installed so as to intersect with the column skin plate 102 in a T-shape, and backing metals 103 and 104 are installed on both sides of the thickness direction of the diaphragm 101 at the intersection with the column skin plate 102. Furthermore, an electroslag-welded metal part 106 is formed in a position surrounded by the diaphragm 101, the column skin plate 102, and the backing metals 103 and 104. In the structure shown in Figure 20, a fillet weld 107 is formed at the intersection between the outer side surfaces of the backing metals 103 and 104 and the inner surface of the column skin plate 102, and a fillet weld 108 is formed at the intersection between the side surface adjacent to the outer side surface of the backing metals 103 and 104 and the front or back surface of the diaphragm 101.

[0004] Electroslag welding involves welding with a large welding heat input of 400 to 1300 kJ / cm, so a welding heat-affected zone 106a is formed around the welding heat affected zone 106a due to the heat of the electroslag welding, and there is a problem that the toughness of this welding heat-affected zone 106a may be inferior to that of the base material. Furthermore, electroslag welding is performed in the groove surrounded by the diaphragm 101, column skin plate 102, and backing metals 103 and 104. However, after welding, unwelded areas (slits) 105 remain between the backing metals 103 and 104 and the column skin plate 102, as shown in Figures 20 and 21. Note that Figure 21 shows a structure in which the beam flange 110 is metal-arc welded to the outside of the column skin plate 102. The tip 105a of the aforementioned slit 105 is the portion located at the tip of the slit, and if a tensile force acts in the material axis direction of the beam flange and the material axis direction of the column skin plate as shown by the arrows in Fig. 21 due to a major earthquake or the like, there is a problem that fracture may occur originating from the electroslag weld metal zone as shown in Fig. 22. In particular, if the toughness of the weld heat-affected zone 106a is low, early brittle fracture may occur before the beam member exhibits the expected yield strength.

[0005] In order to prevent early brittle fracture from the tip of the slit 105, one possible method is to securely fix the backing plates 103, 104 and the column skin plate 102 by assembly welding or the like, thereby preventing the slit 105 from opening in the event of a major earthquake and avoiding strain concentration at the tip of the slit 105. When manufacturing a box column 100, three column skin plates 102 are assembled in a U-shape when viewed from the side as shown in Fig. 23 to form three faces of the box column 100, and then the remaining face (lid face) is covered with the other column skin plate 102. Figs. 23 and 24 show the state just before backing metals 103 and 104 are joined to the lid face side of the diaphragm 101 by fillet welding and the skin plate 102 is placed on top of the joined backing metals 103 and 104. When assembling the box column 100, it is possible to assemble and weld the backing metals 103, 104 and the skin plate 102 on the three sides other than the cover surface. However, on the cover surface side, the backing metals 103, 104 and their surroundings are enclosed by the column skin plate 102, so there is a problem that welding of the backing metals 103, 104 is basically impossible.

[0006] In a structure in which the joint between a column skin plate and a diaphragm is welded, a known structure is one in which a square groove is provided on the side of the backing plate that contacts the skin plate to create a gap that becomes an inclined opening, and the gap is completely embedded and joined with a fillet weld, as described in Patent Document 1 below. Furthermore, in a structure in which the joint between the column skin plate and the diaphragm is welded, a structure is known in which a number of through slits are formed through the diaphragm in the thickness direction, and at least one slit remains after welding, as described in Patent Document 2 below. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 08-155661 [Patent Document 2] Japanese Patent Application Laid-Open No. 2008-280759 Summary of the Invention [Problem to be solved by the invention]

[0008] The conventional methods described in Patent Documents 1 and 2 have the problem that they cannot solve the above-mentioned problems.

[0009] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a welded box section column and a manufacturing method thereof that can suppress early brittle fracture from the slit opening around the electroslag welded metal part when stress is applied to the welded part when an external force such as an earthquake acts on the column. [Means for solving the problem]

[0010] (1) In order to solve the above-mentioned problems, one embodiment of the present invention provides a welded box section column having column skin plates arranged on four sides around the periphery, one or more diaphragms on the inside of the four side column skin plates, and backing metals arranged so as to sandwich the peripheral part of the diaphragm from both sides in the thickness direction of the diaphragm at a position where the peripheral part of the diaphragm is adjacent to the inner surface of the column skin plate, and an electroslag welded metal part is arranged at a position surrounded by the inner surface of the column skin plate, the peripheral part of the diaphragm, and the backing metal, and the peripheral In the case of a column skin plate on three sides around the circumference, a first fillet weld is formed between the column skin plate and the backing metal, and a second fillet weld is formed between the backing metal and the peripheral portion of the diaphragm; in the case of a column skin plate on the remaining side around the circumference, a first fillet weld is formed between the column skin plate and the backing metal, or a second fillet weld is formed between the backing metal and the diaphragm in addition to the first fillet weld, and the length of the first fillet weld in the column width direction is at least equal to or greater than the width of the beam used for column connection plus twice the plate thickness.

[0011] (2) In the welded box section column according to the present invention described in (1), it is preferable that the three column skin plates arranged around the periphery have the first fillet weld between each of the backing metals that sandwich the peripheral portion of the diaphragm from both sides in the thickness direction and the inner surface of the column skin plate. (3) In the welded box section column described in (1) of the present invention, it is preferable that the three column skin plates arranged around the circumference have the first fillet weld between each of the backing metals that sandwich the peripheral portion of the diaphragm from both sides in the thickness direction and the inner surface of the column skin plate, and the remaining column skin plate arranged around the circumference has the first fillet weld between one of the backing metals that sandwich the peripheral portion of the diaphragm from both sides in the thickness direction and the column skin plate, and the second fillet weld between the other of the backing metals that sandwich the peripheral portion of the diaphragm from both sides in the thickness direction and the peripheral portion of the diaphragm.

[0012] (4) In the welded box section column according to any one of (1) to (3) of the present invention, it is preferable that the remaining column skin plate arranged around the periphery has a second fillet weld between the column skin plate and the backing metal, and the length of the second fillet weld in the column width direction is equal to or greater than the width of the beam used for column connection plus twice the plate thickness. (5) In the welded box section column according to any one of (1) to (3) of the present invention, it is preferable that an adhesive layer is provided between a part of the backing metal and the inner surface of the column skin plate.

[0013] (6) A method for manufacturing a welded box section column according to one embodiment of the present invention is a method for manufacturing a welded box section column having column skin plates arranged on four circumferential surfaces, one or more diaphragms on the inside of the column skin plates on the four surfaces, and backing metals arranged at a position where the peripheral portion of the diaphragm is adjacent to the inner surface of the column skin plate so as to sandwich the peripheral portion of the diaphragm from both sides in the thickness direction of the diaphragm, wherein the column skin plates are arranged in a U-shape in side view so as to be arranged on three circumferential surfaces, and the backing metals are arranged in a U-shape in side view on the inner surface of the column skin plates arranged in a U-shape in side view so as to sandwich the peripheral portion of the installation position of the diaphragm from both sides in the thickness direction of the diaphragm, In the case of the column skin plate, a first fillet weld is formed between the column skin plate and the backing metal, and a second fillet weld is formed between the backing metal and the peripheral portion of the diaphragm, and an additional backing metal is temporarily placed on the backing metal arranged in a U-shape when viewed from the side so that it forms an opening when viewed from the side, together with other backing metals, and after forming an adhesive layer on its upper surface, the column skin plate for the remaining side is aligned with and placed over the column skin plates arranged on three sides, the backing metal is temporarily fixed at the desired position of the column skin plate for the remaining side by the adhesive layer, and after the column skin plate for the remaining side is removed from the welded box section column, a first fillet weld is formed between the column skin plate and the temporarily fixed backing metal.

[0014] (7) In the manufacturing method of a welded box section column according to the present invention described in (6), it is preferable that in the three column skin plates arranged around the periphery, the first fillet weld is formed between each of the backing metals that sandwich the peripheral portion of the diaphragm from both sides in the thickness direction and the inner surface of the column skin plate. (8) In the manufacturing method of a welded box section column described in (6) of the present invention, it is preferable that in three column skin plates arranged around the circumference, the first fillet weld is formed between each of the backing metals that sandwich the peripheral portion of the diaphragm from both sides in the thickness direction and the inner surface of the column skin plate, and in the remaining column skin plate arranged around the circumference, the first fillet weld is formed between one of the backing metals that sandwich the peripheral portion of the diaphragm from both sides in the thickness direction and the column skin plate, and the second fillet weld is formed between the other of the backing metals that sandwich the peripheral portion of the diaphragm from both sides in the thickness direction and the peripheral portion of the diaphragm.

[0015] (9) In the method for manufacturing a welded box section column according to any one of (6) to (8) of the present invention, it is preferable that the length of the first fillet weld in the column width direction is at least equal to or greater than the combined width of the beam used for column connection and twice the plate thickness. (10) It is preferable that the length of the second fillet weld in the column width direction is equal to or greater than the sum of the width of the beam for column connection and twice the plate thickness. (11) In the method for manufacturing a welded box section column according to any one of (6) to (9) of the present invention, it is preferable to form an electroslag welded metal part in the space surrounded by the peripheral part of the diaphragm, the column skin plate, and the backing metal. [Effects of the Invention]

[0016] In the present invention, in three of the four column skin plates, all of the backing metals are joined to the inner surface of the column skin plate via first fillet welds and to the peripheral portion of the diaphragm via second welds, and in the remaining column skin plate, at least one of the pair of backing metals sandwiching the diaphragm is joined to the column skin plate via the first fillet weld. Also, an electroslag welded metal is provided at a position surrounded by the inner surface of the column skin plate, the peripheral portion of the diaphragm, and the backing metal. Therefore, even if a slit exists between the backing metal and the inner surface of the column skin plate, the opening behavior at the tip of the slit can be suppressed around the entire circumference of the diaphragm, thereby suppressing early brittle fracture. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is an exploded perspective view showing a welded box section column according to a first embodiment of the present invention; [Figure 2] A cross-sectional view showing the welded joint between the column skin plate, which forms the cover surface, the backing plate, and the diaphragm in the same welded box section column. [Figure 3] A cross-sectional view showing the welded joints between the column skin plate, backing plate, and diaphragm on three sides other than the cover surface of the same welded box section column. [Figure 4] FIG. 10 is an explanatory diagram showing the state in which the diaphragm is aligned between adjacent backing plates in the welded box section column. [Figure 5] A partial cross-sectional view showing the relationship between the position of the beam and the length of the fillet weld when a beam is joined to the side of a column skin plate. [Figure 6] FIG. 1 is a cross-sectional view showing the position of a fillet weld according to the present invention in a structure in which a beam is joined to the four sides of a column skin plate and a backing metal is provided. [Figure 7] This shows an overview of the method for manufacturing a welded box section column of the first embodiment, and is an explanatory diagram showing an example of providing an adhesive layer when assembling the column skin plates on three sides and then joining the column skin plate on the remaining side. [Figure 8]This shows an overview of the method for manufacturing a welded box section column of the first embodiment, and is an explanatory diagram showing a backing metal adhered to a column skin plate when joining the remaining column skin plate after assembling the column skin plates on three sides. [Figure 9] This is an explanatory diagram showing an overview of the method for manufacturing a welded box section column of the first embodiment, and shows the state in which the column skin plate on three sides has been assembled and then the column skin plate on the remaining side has been joined. [Figure 10] FIG. 1 is an explanatory diagram showing an example of an application range of adhesive around an electroslag welded metal portion and a fillet weld portion. [Figure 11] FIG. 10 is an explanatory diagram showing the out-of-plane deformation behavior of the column skin plate when stress is applied due to an earthquake to a structure in which a beam is joined to a welded box section column of the first embodiment. [Figure 12] FIG. 10 is an explanatory diagram showing a state in which a diaphragm is aligned between adjacent backing metals in the welded box section column according to a modified example. [Figure 13] A cross-sectional view showing the position of a fillet weld as a comparative example in a structure in which a beam is joined to the four sides of a column skin plate and a backing metal is provided. [Figure 14] An explanatory diagram showing the stress acting from the flange of a beam when the beam is joined to the side of a column skin plate. [Figure 15] An explanatory diagram showing the stress acting from the web of a beam when the beam is joined to the side of a column skin plate. [Figure 16] An explanatory diagram showing the stress acting on the diaphragm when a beam is joined to the side of a column skin plate. [Figure 17]1 shows the process for fabricating a typical welded box section column using four column skin plates. (a) is an explanatory diagram showing the state in which a column skin plate for one side is installed on a column skin plate that has been assembled on three sides for assembly welding. (b) is an explanatory diagram showing the process of rotating the entire structure by 90 degrees after assembly and welding. (c) is an explanatory diagram showing the process of welding the corners of the column skin plate, drilling holes, and rotating the entire structure by 180 degrees. (d) is an explanatory diagram showing the state in which the remaining corners are welded and drilling holes after rotating the entire structure by 180 degrees. (e) is an explanatory diagram showing the state in which drilling holes is performed after rotating the entire structure by 180 degrees. (f) is an explanatory diagram showing the state in which electroslag welding is performed using the drill holes. (g) is an explanatory diagram showing the state in which the entire structure is rotated by 180 degrees after drill holes have been formed. (h) is an explanatory diagram showing the state in which drill holes are formed after rotating 180 degrees. (i) is an explanatory diagram showing the state in which electroslag welding is performed using the drill holes. [Figure 18] 1 shows an example of a process for manufacturing a welded box section column of the first embodiment, where (a) is an explanatory diagram showing the state in which the column skin plates and backing metal on three sides are assembled, an adhesive layer is formed on the backing metal for the remaining side, and the column skin plate for the remaining side is placed opposite it, (b) is an explanatory diagram showing the column skin plate for the remaining side being placed on top of the adhesive layer and then the column skin plate for the remaining side being removed, (c) is an explanatory diagram showing the state in which the backing metal adhered to the removed column skin plate for the remaining side is fillet welded and then aligned again with the column skin plates on the other three sides, and (d) is an explanatory diagram showing the state in which the column skin plates on all four sides are assembled and then the whole is rotated. [Figure 19] FIG. 1 is a perspective view showing the structure of a typical welded box section column. [Figure 20] 20 is a cross-sectional view showing an example of an electroslag welded metal part in the welded box section column shown in FIG. 19. FIG. [Figure 21] 20 is a cross-sectional view showing an example of an electroslag welded metal part in the welded box section column shown in FIG. 19. FIG. [Figure 22] FIG. 22 is an explanatory diagram showing the electroslag welded metal joint shown in FIGS. 20 and 21 undergoing early brittle fracture due to earthquake shaking. [Figure 23] This is an explanatory diagram of the process for assembling a typical welded box section column using four column skin plates. [Figure 24] An explanatory diagram showing the state in which the column skin plate, which serves as the cover surface, is brought close to the backing metal attached to the outer periphery of the diaphragm in the same welded box section column. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the drawings used in the following description of the embodiments, characteristic portions may be enlarged or otherwise emphasized for the sake of clarity. In addition, common components in the description of the embodiments are given the same reference numerals, and descriptions of components with the same reference numerals may be simplified or omitted.

[0019] "First embodiment" Hereinafter, a welded-assembled box section column according to a first embodiment of the present invention will be described with reference to Figs. The welded box section column 1 according to the first embodiment is assembled into a square tubular shape by joining four column skin plates 2 made of strip-shaped steel plates together by welding their long sides together. To make the internal structure easier to see, Figure 1 shows a perspective view of the welded box section column 1 when it is arranged horizontally, and also shows an exploded view in which the upper one of the four column skin plates 2 is separated from the other three column skin plates 2. The other three column skin plates 2 are joined in a U-shape in side view via corner welds 3 made by submerged arc welding or the like on their long sides. Note that in Figure 1, the corner welds that join the column skin plate 2 for the remaining side, separated at the top, to the column skin plates 2 for the other three sides are omitted.

[0020] A plurality of diaphragms 5 are provided inside the welded box column 1. The diaphragms 5 are made of approximately rectangular steel plates and are arranged approximately perpendicular to the column skin plate 2 so as to divide the interior space of the welded box column 1 into multiple spaces in the longitudinal direction. In FIG. 1, two diaphragms 5 are arranged at a predetermined interval inside the welded box column 1 along the longitudinal direction of the welded box column 1. The number of diaphragms 5 provided inside the welded box column 1 can be any number greater than or equal to one, taking into account the shape of the beam to be joined to the welded box column 1, etc. In addition, the diaphragm 5 in this example has shallow recesses 5a at its upper and lower ends along the width direction, and protrusions 5b on both ends of the recesses 5a, forming a roughly H-shaped configuration in front view.

[0021] Around the periphery of each diaphragm 5, square bar-shaped backing metals 6 are arranged on both sides in the thickness direction. In the welded-assembled box section column 1 shown in Fig. 1 as an exploded view, three backing metals 6 are arranged along the periphery of each diaphragm 5 to form a U-shape in side view. Also, a backing metal 6 is drawn on the underside of one of the column skin plates 2 drawn separately at the top in Fig. 1. When the column skin plate 2 drawn separately at the top is welded and integrated with another column skin plate 2, the backing metal 6 drawn on the underside of the upper column skin plate 2 is combined with the other three backing metals 6 to form an open rectangular frame in side view.

[0022] Four column skin plates 2 are integrated into a square cylindrical shape, and backing metals 6 are placed in a mouth-shaped manner around the periphery of each diaphragm 5. Electroslag welding is then performed on the inner surfaces of the column skin plates 2 and the areas surrounded by the diaphragms 5 and backing metals 6, 6, as shown in Figures 2 and 3, to form electroslag welded metal parts 7, 8, thereby constructing a welded box section column 1. FIG. 2 shows an electroslag welded metal portion 7 formed in the area surrounded by the column skin plate 2 separated at the top in FIG. 1, its inner backing metals 6, 6, and the diaphragm 5. FIG. 3 shows an electroslag welded metal portion 8 formed in a region surrounded by any of the other three column skin plates 2 shown in FIG. 1, their inner backing metals 6, 6, and a diaphragm 5.

[0023] In FIG. 2, the inner surface position of the column skin plate 2, the outer peripheral end face position of the diaphragm 5, and the side positions of the backing metals 6, 6 before the electroslag welded metal portion 7 is formed are indicated by chain lines. In FIG. 3, the position of the inner surface of the column skin plate 2, the position of the outer peripheral end face of the diaphragm 5, and the position of the side surfaces of the backing metals 6, 6 before the electroslag welded metal part 8 is formed are indicated by chain lines. As shown in Figures 1 to 3, a welded box cross-section column 1 of this embodiment has column skin plates 2 arranged on four sides around its periphery, and two diaphragms 5 on the inside of the four side column skin plates 2. In addition, backing metals are arranged at a position where the peripheral portion of the diaphragm 5 is adjacent to the inner surface of the column skin plate 2, so as to sandwich the peripheral portion of the diaphragm 5 from both sides in the thickness direction of the diaphragm 5. In addition, an electroslag welded metal part is formed at a position surrounded by the inner surface of the column skin plate 2, the peripheral portion of the diaphragm 5, and the backing metals 6.

[0024] As shown in Fig. 2, one (right) backing strip 6 provided on the inner surface of the column skin plate 2 is attached to the inner surface of the column skin plate 2 by a first fillet weld 10 formed on the side of the backing strip 6 opposite (right) the side on which the electroslag welded metal portion 7 is provided. Of course, this right-side backing strip 6 is also fixed to the column skin plate 2 by the electroslag welded metal portion 7 formed so as to share a portion of the inner surface of the column skin plate 2 with a portion of the left side of the backing strip 6. The first fillet weld 10 is formed along the portion where the right side surface of the right-side backing strip 6 and the inner surface of the column skin plate 2 contact in Fig. 2, so as to have a predetermined length (described later) in the direction perpendicular to the plane of the paper on which Fig. 2 is drawn.

[0025] As shown in Fig. 2, the other (left) backing strip 6 provided on the inner surface of the column skin plate 2 is attached to the inner surface of the column skin plate 2 by a first fillet weld 11 formed on the side of the backing strip 6 opposite (left side) the side on which the electroslag welded metal portion 7 is provided. Of course, this left-side backing strip 6 is also fixed to the column skin plate 2 by the electroslag welded metal portion 7 formed so as to share a portion of the inner surface of the column skin plate 2 with a portion of the right side of the backing strip 6. The first fillet weld 11 is formed along the portion where the left side surface of the left-side backing strip 6 and the inner surface of the column skin plate 2 contact in Fig. 2, so as to have a predetermined length (described later) in the direction perpendicular to the plane of the paper on which Fig. 2 is drawn.

[0026] Figure 5 shows an example of the desirable length of the fillet weld 10 (length in the column width direction) when the column skin plate 2 and backing plate 6 are fixed by fillet welding. Figure 5 is a plan view of a vertically erected welded box section column 1, showing a state in which a beam 13 is joined to one of the column skin plates 2 located on its side. A beam 13 having a width H1, as shown in FIG. 5, is typically connected to a welded box column 1. The length H2 of the first fillet weld 10 (the width forming the first fillet weld 10) shown in FIG. 5 must be equal to or greater than the width H1 of the beam 13. Furthermore, the length H2 of the first fillet weld 10 shown in FIG. 5 is preferably equal to or greater than the width H1 of the beam 13 plus twice the thickness of the column skin plate 2. In FIG. 5, the length H2 of the first fillet weld 10 is depicted as being approximately equal to the width H1 of the beam 13 plus twice the thickness of the column skin plate 2. If the beam 13 for column connection described above is made of a typical H-shaped steel with flanges on both sides of the web, H1 can also be interpreted as the flange width.

[0027] FIG. 6 is a plan view showing a state in which beams 13 are joined to the column skin plates 2 located on the four side faces of a vertically erected welded box section column 1. When a first fillet weld 10 is formed as shown in Fig. 2 for a column skin plate 2 shown separated on the upper side as shown in Fig. 1, the length of the first fillet weld 10 is set as shown in Fig. 5 and Fig. 6. The length of the first fillet weld 10 and the length of the first fillet weld 11 are set to be equal.

[0028] In contrast to these, for three column skin plates 2 assembled in a U-shape in side view as shown in Figure 1, first fillet welds 15, 16 are formed on both sides of backing metal 6 as shown in Figure 3, and second fillet welds 17, 18 are also formed between backing metal 6 and diaphragm 5.

[0029] As shown in Fig. 3, one (right) backing metal 6 provided on the inner surface of the column skin plate 2 is attached to the inner surface of the column skin plate 2 by a first fillet weld 15 formed on the side of the backing metal 6 opposite (right side) to the side where the electroslag welded metal portion 8 is provided. Of course, this right-side backing metal 6 is also fixed to the column skin plate 2 by the electroslag welded metal portion 8 formed so as to share a part of the inner surface of the column skin plate 2 with a part of the left side of the backing metal 6. The first fillet weld 15 is formed along the part where the right side surface of the right-side backing metal 6 and the inner surface of the column skin plate 2 contact in Fig. 3, so as to have a predetermined length (described later) in the direction perpendicular to the plane of the paper on which Fig. 3 is drawn.

[0030] As shown in Fig. 3, the other (left) backing strip 6 provided on the inner surface of the column skin plate 2 is attached to the inner surface of the column skin plate 2 by a first fillet weld 16 formed on the side of the backing strip 6 opposite (left side) to the side on which the electroslag welded metal portion 8 is provided. Of course, this left-side backing strip 6 is also fixed to the column skin plate 2 by the electroslag welded metal portion 8 formed so as to share a portion of the inner surface of the column skin plate 2 with a portion of the right side of the backing strip 6. The first fillet weld 16 is formed along the portion where the left side surface of the left-side backing strip 6 and the inner surface of the column skin plate 2 contact in Fig. 3, so as to have a predetermined length (described later) in the direction perpendicular to the plane of the paper on which Fig. 3 is drawn.

[0031] As shown in Fig. 3, a second fillet weld 17 having a predetermined length, described later, is formed along the direction perpendicular to the plane of the paper in Fig. 3 at the boundary between one (right) backing metal 6 provided on the inner surface of the column skin plate 2 and the adjacent diaphragm 5. Also, a second fillet weld 18 having a predetermined length, described later, is formed along the direction perpendicular to the plane of the paper in Fig. 3 at the boundary between the other (left) backing metal 6 provided on the inner surface of the column skin plate 2 and the adjacent diaphragm 5.

[0032] Figure 6 shows a state in which a beam 13 is joined to each column skin plate 2 of a vertically erected welded box section column 1, and the first fillet weld 15 shown in Figure 3 is also shown in Figure 6. As shown in Figure 6, beams 13 are joined to each of the three column skin plates 2 arranged in a U-shape when viewed from the side in Figure 1, and first fillet welds 15 shown in Figure 3 are formed on the three column skin plates 2. As an example, the lengths of first fillet weld 15 and second fillet weld 17 are equal to each other, and are equal to the length of first fillet weld 10 described above. Therefore, the first fillet weld 15 (the width forming the first fillet weld 15) H3 must be equal to or greater than the width H1 of the beam 13. Also, the length H3 of the first fillet weld 15 shown in Fig. 6 must be equal to or greater than the width H1 of the beam 13 plus twice the thickness of the column skin plate 2. The length of the second fillet weld 17 (the width forming the second fillet weld 17) is sufficient if it is long enough to temporarily fasten the diaphragm and the backing metal, but to prevent fracture from the diaphragm side, it is preferable that the length be equal to or greater than the width H1 of the beam 13 plus twice the thickness of the column skin plate 2. In FIG. 5, the length H3 of the first fillet weld 15 is depicted as being approximately equal to the combined length of the width H1 of the beam 13 and twice the thickness of the column skin plate 2.

[0033] "Outline of manufacturing method for welded box section columns" The welded box section column 1 having the structure shown in Figs. 1 to 6 can be assembled by the method described below with reference to Figs. 7 to 9, as an example. In the embodiment described below, as shown in Fig. 7, the opening on the top side, which is made up of three column skin plates 2 arranged in a U-shape when viewed from the side, is closed with the remaining column skin plate 2 to form a square cylindrical assembly. In view of this relationship, the opening on the top side, which is made up of three column skin plates 2 as shown in Fig. 1, is sometimes referred to as the cover surface, and the remaining column skin plate 2 that closes this cover surface is sometimes referred to as the column skin plate 2 on the cover surface side. As shown in Figure 7, three column skin plates 2 are used, and the long sides of the column skin plates 2 are butted together to form a U-shape when viewed from the side, and the three column skin plates are temporarily assembled using backing metal or welding. In Figure 7, the position of the backing metal when provided along the butt joints of the column skin plates 2 is shown by a two-dot chain line. The column skin plates 2 are temporarily assembled in a U-shape when viewed from the side, with a three-sided arrangement around the perimeter.

[0034] Additionally, backing metals 6, 6 are attached to the three column skin plates 2 in advance by assembly welding using fillet welds so that the diaphragm 5 can be held in place. The backing metals 6, 6 are arranged in a U-shape in side view so as to sandwich the periphery of the installation position of the diaphragm 5 from both sides in the thickness direction of the diaphragm 5. In this embodiment, two diaphragms 5 are provided at a predetermined interval inside the welded box section column 1, and two diaphragms 5 are installed at the installation positions of the two diaphragms 5, and backing metals 6 are fixed to the peripheral portions of the diaphragms 5 and the inner surface of each column skin plate 2 by fillet welding. When the three column skin plates 2 are connected in a U-shape as seen from the side as shown in FIG. 7, a backing metal 6 is also arranged in a U-shape inside them.

[0035] Since there is nothing placed on top of the three backing metals 6, 6 arranged in a U-shape, a fourth backing metal 6 is placed on top of the backing metals 6, 6 arranged in a U-shape, aligning it as shown in Figure 7. By placing the fourth additional backing metal 6, it is possible to temporarily place four backing metals 6 in the mouth mold. Here, an adhesive is applied to the top surface of the fourth backing metal 6 to form an adhesive layer 20 as shown in Figure 7.

[0036] 7, the column skin plate 2 on the lid side is lowered and placed over the lid surface consisting of three skin plates 2 arranged in a U-shape when viewed from the side. When placing the column skin plate 2 on the lid side over the column skin plates 2 arranged in a U-shape when viewed from the side, the column skin plate 2 is placed over the column skin plates 2 while accurately positioning it so as to form a welded box section column 1 of the desired shape. Since the adhesive layer 20 is present on the upper surface of the backing metal 6 located on the lid side, the underside of the column skin plate 2 on the lid side comes into contact with the adhesive layer 20. Thereafter, the adhesive layer 20 is hardened. This hardening process allows the backing metals 6, 6 to be adhered and fixed accurately at the desired positions on the underside of the column skin plate 2 on the lid side. Once the adhesive has solidified, even if the column skin plate 2 on the cover side is raised and separated from the other three column skin plates 2 as shown in Figure 8, the backing metals 6, 6 can be adhered to the desired position on the underside of the upper column skin plate 2 and maintained in a fixed state.

[0037] After this, assembly welding can be performed by fillet welding the adhered backing metal 6 to form the first fillet welds 10, 11 shown in Fig. 2. Fig. 8 shows the backing metals 6, 6 fixed to the column skin plate 2 on the cover surface side by adhesive, and the positions of the first fillet welds 10, 11 formed on the backing metals 6, 6 are indicated by thick lines. After this, when the column skin plate 2 on the cover side is placed over the column skin plate 2 arranged in a U-shape when viewed from the side as shown in Figure 9, the diaphragm 5 is supported with its peripheral portion sandwiched between backing metals 6, 6 arranged in a mouth-like shape on the inside of the four column skin plates 2.

[0038] After this, the grooves formed at the corners of the square cylindrical steel pipe composed of the column skin plates 2 arranged in a U-shape when viewed from the side and the column skin plate 2 on the cover side are corner-welded by submerged arc welding or CO2 welding to form corner welds, thereby achieving an approximate shape similar to the welded-assembled box cross-section column 1 of this embodiment. After this, a drill hole is formed at any position on the column skin plate 2 so as to communicate with the space between the inner surface of the column skin plate 2, the backing metals 6, 6, and the diaphragm 5, as shown in Figure 2 or Figure 3, and electroslag welding is performed using this drill hole to form electroslag welded metal parts 7, 8, thereby obtaining the welded-assembled box section column 1 of the first embodiment. The order of corner welding and electroslag welding is arbitrary, and corner welding may be performed after joining the diaphragm and the column skin plate by electroslag welding.

[0039] As the electroslag welding method, any commonly known method can be used. For example, as shown in Figure 19, an electroslag weld metal joint can be formed by passing current through a welding wire 120 to form a molten slag bath in the groove, and gradually cooling the molten slag bath from the bottom while raising the molten slag together with the welding wire 120. The welding direction is usually upward. Details of the manufacturing method for the welded box section column 1 of this embodiment and the order of the electroslag welding method will be described in detail in an example to be explained later.

[0040] In the manufacturing method described above, an adhesive layer 20 was formed on the fourth backing plate 6, which was positioned relative to the three backing plates 6 arranged in a U-shape when viewed from the side, as shown in Figure 7, and this adhesive layer 20 was used to temporarily fix the fourth backing plate 6 to the column skin plate 2 on the lid surface side. FIG. 10 is an explanatory diagram showing a desirable range when the adhesive layer 20 is applied to the fourth backing metal 6. As shown in FIG. The adhesive layer 20 is made of resin, and there is a risk that the resin of the adhesive will penetrate into the weld when fillet welding or electroslag welding is performed. If the adhesive penetrates into the weld, this could result in a defective weld. Therefore, it is desirable to form the adhesive layer 20 in a position sufficiently separated from the fillet welds 10, 11 and the electroslag welded metal part 7. To achieve this, it is desirable to form the adhesive layer 20 in a position approximately 5 mm away from the positions that will become the grooves for the fillet welds and the electroslag welds, as shown in the plan view of FIG. 10. FIG. 10 shows adhesive layer 20 applied to a region that is 5 mm or more away from electroslag weld metal portion 7 and 5 mm or more away from first fillet weld portion 10. By forming adhesive layer 20, when the strength of first fillet weld 10 becomes insufficient during an earthquake and first fillet weld 10 breaks, adhesive layer 20 can prevent the slit from opening. Therefore, it can be expected that the presence of adhesive layer 20 can provide a fail-safe function against breakage of first fillet weld 10.

[0041] Figure 11 shows an example of the out-of-plane deformation behavior of a column skin plate 2 during an earthquake when a beam flange 21 is joined to the column skin plate 2 of a welded box section column 1 in line with the installation position of a diaphragm 5. The beam flange 21 is joined to the column skin plate 2 via a full penetration weld 21a by gas metal arc welding. A tensile force is applied to the beam flange 21 in the upper part of Figure 11 when the moment is replaced by a couple force, as indicated by the right-pointing arrow, and a similar tensile force is applied to the beam flange 21 in the lower part of Figure 11, as indicated by the left-pointing arrow. As a result, a moment is applied to the beam as indicated by the clockwise arrow in the center of Figure 11. Considering the deformation behavior shown in Figure 11, assuming that slits are formed between the electroslag welded metal part 7 and the first fillet welds 10, 11, and between the electroslag welded metal part 8 and the first fillet welds 15, 16, as shown in Figures 2 and 3, it is considered more important to form the fillet welds on the inner surface of the diaphragm 5 between the upper and lower beam flanges 21, where the opening behavior at the tip of the slit becomes larger.

[0042] As shown in Figure 1, when two diaphragms 5 are installed adjacent to each other in the longitudinal direction of a welded box section column 1 and a beam is attached to the opposing surfaces sandwiching a column skin plate 2, the inner surface side of the diaphragm 5 refers to the first fillet welds provided at the positions of the thick lines 6a along the opposing sides of the two inner backing plates 6 of the four backing plates 6 installed on the column skin plate 2 on the cover side shown in Figure 1. As shown in FIG. 2, it is desirable to provide a first fillet weld 10 on one backing plate 6 and a first fillet weld 11 on the other backing plate 6. However, if priority is given to one of them, it is preferable to provide the first fillet weld 10 or the first fillet weld 11 at the position shown by the thick line 6a in FIG. 1.

[0043] Figure 12 shows an example in which the first fillet weld 10 is provided first, and one backing plate 6 (right side in Figure 12) is assembled and welded to the column skin plate 2 using the first fillet weld 10, and the other backing plate 6 (left side in Figure 12) is assembled and welded to the peripheral portion of the diaphragm 5 using the second fillet weld 19. When installing the column skin plate 2 on the cover side so as to close the cover surface consisting of three column skin plates 2 assembled in a U-shape when viewed from the side as shown in Fig. 1, a welded box section column 1 may be manufactured using the structure shown in Fig. 12. In this manufacturing method, it is not necessarily necessary to bond the backing metal 6 and the column skin plate 2.

[0044] Figure 13 shows an example of a structure in which a welded box-section column is erected vertically, similar to the structure shown in Figure 6, and beams 13 are joined to each of the column skin plates 2 located on the four sides. 13, third fillet welds 23 are formed intermittently along the length of the backing metal 6 corresponding to the column skin plate 2 on the cover surface side. Also, first fillet welds 24 and second fillet welds 25 are formed intermittently along the length of the backing metal 6 corresponding to the column skin plates 2 that make up the other three surfaces. In the structure shown in FIG. 13, the length of each of the third fillet weld 23 , the first fillet weld 24 , and the second fillet weld 25 is shorter than the width of the beam 13 . In the fillet welded structure shown in Figure 13, fillet welds are not necessarily placed in the region (H2) where stress increases during an earthquake. If the fillet weld strength is insufficient and the toughness of the weld heat-affected zone by electroslag welding is insufficient, the structure will be at risk of premature brittle fracture originating from the electroslag weld metal during an earthquake. The reasons for this are explained below.

[0045] Figure 14 shows the range of stress acting on the center of the diaphragm via the flange 28 of the beam when the flange 28 of the beam is joined to the column skin plate 27 of a welded box section column via a weld 29. The width of the beam flange 28 is B, and the thickness of the column skin plate 27 is s Assuming t, the stress transfer range from the flange 28 of the beam is B + 2 × s t, d A stress of σ1 acts. FIG. 15 shows the range of stresses acting from the web of the beam to the center of the diaphragm in a similar case. The width of the beam flange 28 is B, and the thickness of the column skin plate 27 is s Assuming t, the stress transfer range from the web is B+2× s t, d A stress of σ2 acts. Figure 16 shows a stress diagram that sums up the stresses shown in Figures 14 and 15, and the range of stress acting on the diaphragm is B+2× s t, d σ1+ d σ2= d A stress of σ acts.

[0046] From Figures 14 to 16, the stress on the inner diaphragm due to the external force from the beam flange is B+2× s Therefore, it is most desirable that the first fillet weld and the second fillet weld be present so as to cover this range. From the background explained above, it is clear that it is important to adopt the structure shown in FIG. 6 rather than the structure shown in FIG. 13, and that by adopting the structure shown in FIG. 6, it is possible to provide a welded-assembled box section column 1 that has the effect of suppressing early brittle fracture during an earthquake.

[0047] "Method for manufacturing welded box section columns" The outline of the manufacturing method for the welded-assembled box section column 1 according to this embodiment has been explained above with reference to Figs. Hereinafter, an example of an overall outline of a method for manufacturing a welded box section column 1 will be described in more detail with reference to Figures 17(a) to 17(i). The method described with reference to Figures 17(a) to 17(i) includes the order of forming electroslag welded metal parts when manufacturing a welded box section column of a general structure.

[0048] When manufacturing a welded box section column of a general structure, three column skin plates 31, 32, 33 and backing metal plates 34, 35, 36 are assembled by assembly welding so as to form a U-shape in side view as shown in Figure 17(a). In addition, a backing metal plate 37 is joined by assembly welding onto the backing metal plates 34, 35, 36 that have been assembled and welded to form a U-shape in side view so as to form an open shape in side view. Here, assembly welding means fillet welding of the contact portions of the three column skin plates 31, 32, 33 and the backing metals 34, 35, 36 so as to form the arrangement shown in FIG. 17(a). A diaphragm 39 is installed inside the backing metals 34, 35, 36, and 37. Note that, although Fig. 17(a) shows only the backing metals 34, 35, 36, and 37 located on the front side of the diaphragm 39, the backing metals 34, 35, 36, and 37 are installed in a similar arrangement on the back side of the diaphragm 39 shown in Fig. 17(a).

[0049] In addition, in the structure shown in Figure 17(a), inclined surfaces 31a for forming a groove portion are formed on both sides of the width of the column skin plate 31, and inclined surfaces 32a for forming a groove portion are formed on both sides of the width of the column skin plate 32. The entire structure temporarily fixed by assembly welding as shown in FIG. 17(b) is rotated 90 degrees in the clockwise direction indicated by the arrow to obtain the arrangement shown in FIG. 17(c). When the arrangement shown in Figure 17(c) is used, the groove side on which the slope 31a is formed faces upward, so corner welding is performed using a welding method such as submerged arc welding or CO2 welding, and corner welds 40 are formed on both sides of the column skin plate 31 in the width direction.

[0050] After the corner welds 40, 40 are formed, the entire structure is rotated 180° to the position shown in Fig. 17(d), so that the groove side on which the slope 32a is formed faces upward. Corner welding is then performed using a welding method such as submerged arc welding or CO2 welding, and corner welds 41 are formed on both sides in the width direction of the column skin plate 32. In the state shown in Fig. 17(d), the column skin plate 32 and backing metal 35 are positioned on the upper side. After the corner welds 41, 41 are formed, drill holes are drilled as shown by the downward arrows in Fig. 17(d). One drill hole is formed to communicate with the space that exists along the back side of the backing metal 36 shown in Fig. 17(d), and the other drill hole is formed to reach the space that exists along the back side of the backing metal 37. After these drill holes are drilled, the entire structure is rotated 180 degrees to the position shown in Figure 17(e), so that the side with the corner welds 40, 40 faces upward, and drill holes are drilled as shown by the downward arrow. One drill hole is formed to communicate with the space existing along the back side of the backing plate 37 shown in Figure 17(e), and the other drill hole is formed to reach the space existing along the back side of the backing plate 36.

[0051] In the state shown in Figure 17(e), drill holes created as shown in Figure 17(d) are present on both sides in the width direction of the column skin plate 31 located on the lower side. Therefore, the space existing along the back side of the backing plate 36 or the space existing along the back side of the backing plate 37 is opened by drill holes at both the top and bottom ends. In this state, electroslag welding becomes possible, and electroslag weld metal part 42 is formed so as to fill the drill hole from the lower side, fill the space above it, and fill the drill hole above the space, as shown by the upward arrow in Figure 17(f).

[0052] After forming the electroslag welded metal part 42 as shown in Figure 17(f), the entire structure is rotated 90 degrees counterclockwise as shown by the arrow in Figure 17(f), and the column skin plate 38 and backing metal 37 are placed on top as shown in Figure 17(g). 17(g), drill holes are formed through both ends of the column skin plate 38 in the thickness direction as indicated by the downward arrows. One drill hole reaches the space present on the reverse side of the backing metal 34 shown in FIG. 17(g), and the other drill hole reaches the space present on the reverse side of the backing metal 35.

[0053] After drilling the holes, the entire structure is rotated 180° clockwise as shown by the arrow in Figure 17(g), resulting in the state shown in Figure 17(h). In the state shown in Figure 17(h), the column skin plate 33 and backing metal 36 are positioned on the upper side. When the column skin plate 33 is positioned as shown in Figure 17(h), drill holes are formed through both ends of the column skin plate 33 in the thickness direction as indicated by the downward arrows. One drill hole reaches the space behind the backing metal 35 shown in Figure 17(h) and the other drill hole reaches the space behind the backing metal 34.

[0054] In the state shown in Figure 17(h), drill holes created as shown in Figure 17(g) are present on both sides of the width of the column skin plate 38 located at the bottom, so that the space behind the paper of backing plate 35 and the space behind the paper of backing plate 34 are opened by drill holes at both the top and bottom ends. In this state, electroslag welding becomes possible, and electroslag weld metal part 43 is formed so as to fill the drill hole from the lower side, fill the space above it, and fill the drill hole above the space, as shown by the upward arrow in Figure 17(i). By forming the corner welds 40, 41 and the electroslag welded metal parts 42, 43 using the manufacturing method described above, a welded and assembled box section column 45 having an electroslag welded metal part can be manufactured.

[0055] When manufacturing the welded box section column 1 according to the present embodiment described above, the method of forming corner welds to weld the corners of the column skin plates 2 on four sides and forming electroslag welded metal parts 7, 8 can be the same as the method of manufacturing the welded box section column 45 using Figures 17(a) to (i). However, when manufacturing the welded box section column 1 according to this embodiment, the backing metal is temporarily fixed using an adhesive layer. Therefore, taking into consideration the use of an adhesive layer, the manufacturing method of the welded box section column 1 will be described below with reference to Figures 18(a) to (d).

[0056] When manufacturing the welded box section column 1 according to this embodiment, three column skin plates 2 are arranged in a U-shape when viewed from the side, and four backing metal plates 6 are arranged inside the three column skin plates 2 in a square shape when viewed from the side, as shown in Figure 18(a), and an adhesive layer 20 is provided on the upper surface of the upper backing metal 6, as previously explained using Figure 7. The three pillar skin plates 2 are arranged in a U-shape when viewed from the side, and the pillar skin plate 2 on the lid side is aligned and placed on the adhesive layer 20 as shown by the downward arrow in Figure 18(a). After the adhesive has solidified, when the column skin plate 2 on the lid side is raised as shown by the upward arrow in Figure 18(b), the backing metal 6 adhered to a predetermined position on the underside of the column skin plate 2 on the lid side rises together with the column skin plate 2 on the lid side.

[0057] The column skin plate 2 on the cover side has a backing metal 6 temporarily fixed with adhesive in the desired position, so when the first fillet weld 10 is formed in the backing metal 6, the backing metal 6 is joined to the column skin plate 2 on the cover side by assembly welding. When the column skin plate 2 on the cover side is assembled and welded to the other three column skin plates 2 arranged in a U-shape when viewed from the side, the state shown in FIG. 18(d) can be achieved. The state shown in Figure 18(d) is equivalent to the state shown in Figure 17(b), and therefore, by carrying out the method described below based on Figures 17(b) to (h), it is possible to manufacture the welded-assembled box section column 1 of the first embodiment in which each part is joined by corner welds and electroslag welded metal parts, similar to the structure shown in Figure 17(h). [Explanation of symbols]

[0058] 1... Welded box section column, 2...Column skin plate, 5...diaphragm, 6...Backing plate, 7, 8...Electroslag welded metal parts, 10, 11, 15, 16...First fillet weld, 13...beam, 17, 18...Second fillet weld, 20...adhesive layer, 21...Beam flange, H1…beam width, H2: length of the first fillet weld, H3: Length of the second fillet weld 31, 32, 33, 38...Column skin plates, 34, 35, 36, 37...Backing plate, 42, 43...Electroslag welded metal parts.

Claims

1. A welded and assembled box section column having column skin plates arranged on four circumferential surfaces, one or more diaphragms on the inside of the column skin plates on the four surfaces, and backing metals arranged at a position where a peripheral portion of the diaphragm is adjacent to an inner surface of the column skin plate so as to sandwich the peripheral portion of the diaphragm from both sides in the thickness direction of the diaphragm, an electroslag welded metal portion at a position surrounded by the inner surface of the column skin plate, the peripheral portion of the diaphragm, and the backing metal; In the column skin plate on three sides around the circumference, a first fillet weld is formed between the column skin plate and the backing metal, In the column skin plate on the remaining one surface around the circumference, a first fillet weld is formed between the column skin plate and the backing metal, The length of the first fillet weld in the column width direction is at least equal to or greater than the sum of the width of the beam for column connection and twice the plate thickness, Welded box section column.

2. In the three column skin plates arranged around the periphery, the first fillet welds are formed between the inner surface of the column skin plate and each of the backing metals that sandwich the peripheral portion of the diaphragm from both sides in the thickness direction. The welded box section column of claim 1.

3. In the three column skin plates arranged around the periphery, the first fillet welds are formed between the inner surfaces of the column skin plates and the backing metals that sandwich the peripheral portion of the diaphragm from both sides in the thickness direction, The remaining column skin plate arranged around the periphery has the first fillet weld between the column skin plate and one of the backing metals that sandwich the peripheral portion of the diaphragm from both sides in the thickness direction. The welded box section column of claim 1.

4. The remaining column skin plate arranged around the periphery has a second fillet weld between the column skin plate and the backing metal, and the length of the second fillet weld in the column width direction is equal to or greater than the sum of the width of the column-connecting beam and twice the plate thickness. The welded box section column according to any one of claims 1 to 3.

5. an adhesive layer between a portion of the backing metal and the inner surface of the column skin plate; The welded box section column according to any one of claims 1 to 3.

6. A method for manufacturing a welded and assembled box section column having column skin plates arranged on four sides around the periphery, one or more diaphragms on the inside of the column skin plates on the four sides, and backing metals arranged at a position where a peripheral portion of the diaphragm is adjacent to an inner surface of the column skin plate so as to sandwich the peripheral portion of the diaphragm from both sides in the thickness direction of the diaphragm, The column skin plate is arranged in a U-shape in side view so as to be arranged on three sides around the circumference, and the backing metal is arranged in a U-shape in side view on the inner surface side of the column skin plate arranged in a U-shape in side view so as to sandwich the peripheral portion of the installation position of the diaphragm from both sides in the thickness direction of the diaphragm, For a column skin plate arranged on three sides, a first fillet weld is formed between the column skin plate and the backing metal, and a second fillet weld is formed between the backing metal and a peripheral portion of the diaphragm; The backing plate is temporarily placed on the backing plate arranged in a U-shape in side view together with the other backing plates so that it forms an opening in side view, and an adhesive layer is formed on the upper surface thereof. After that, the column skin plate for the remaining one side is aligned with and placed over the column skin plates arranged on three sides, and the backing plate is temporarily fixed at the desired position of the column skin plate for the remaining one side by the adhesive layer. After the column skin plate for the remaining one side is removed from the welded box section column, a first fillet weld is formed between the column skin plate and the temporarily fixed backing plate. Manufacturing method for welded assembled box section columns.

7. In the three column skin plates arranged around the periphery, the first fillet welds are formed between the inner surfaces of the column skin plates and the backing metals that sandwich the peripheral portion of the diaphragm from both sides in the thickness direction. The method for manufacturing a welded box section column according to claim 6.

8. In the three column skin plates arranged around the periphery, the first fillet welds are formed between the inner surfaces of the column skin plates and the backing metals that sandwich the peripheral portion of the diaphragm from both sides in the thickness direction, In the remaining column skin plate arranged around the periphery, the first fillet weld is formed between the column skin plate and one of the backing metals sandwiching the peripheral portion of the diaphragm from both sides in the thickness direction, and the second fillet weld is formed between the peripheral portion of the diaphragm and the other of the backing metals sandwiching the peripheral portion of the diaphragm from both sides in the thickness direction. The method for manufacturing a welded box section column according to claim 6.

9. The length of the first fillet weld in the column width direction is at least equal to or greater than the combined width of the beam for column connection and twice the plate thickness, The method for manufacturing a welded assembled box section column according to any one of claims 6 to 8.

10. The length of the second fillet weld in the column width direction is equal to or greater than the sum of the width of the beam for column connection and twice the plate thickness, The method for manufacturing a welded box section column according to claim 9.

11. forming an electroslag welded metal part in a space surrounded by the peripheral part of the diaphragm, the column skin plate, and the backing metal; The method for manufacturing a welded assembled box section column according to any one of claims 6 to 8.

Images