Joint structure between square steel pipe column and H-shaped steel beam and manufacturing method for the joint structure

Abstract

To provide a bonding structure of a square steel pipe column and an H-shaped steel beam and a manufacturing method of the bonding structure having high manufacturing efficiency and capable of reliably securing assembly accuracy of members.SOLUTION: Provided is a bonding structure of a square steel pipe column and an H-shaped steel beam in which the H-shaped steel beam is bonded to the square steel pipe column via an outer diaphragm. A hole for welding surrounded by a patch is provided in between a side surface of the square steel pipe column and an end surface of the outer diaphragm. The square steel pipe column and the outer diaphragm are bonded to each other by a welding part formed by filling a molten metal into the hole for welding by electroslag welding.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a joint structure between a column and a beam in a building and a manufacturing method for the joint structure, and in particular to a joint structure between a square steel pipe column and an H-shaped steel beam. [Background technology]

[0002] Square steel pipes, such as cold roll-formed square steel pipes and cold press-formed square steel pipes, are widely used as pillar materials for low-rise to high-rise steel buildings. At the joints between square steel pipe columns and H-shaped steel beams, when horizontal forces act on the building during earthquakes, etc., stress is transmitted from the flange of the H-shaped steel beam to the side of the square steel pipe column. To prevent local deformation on the side of the square steel pipe column due to this stress, horizontal stiffening members called diaphragms are generally installed on the square steel pipe columns at the same height as the flange of the H-shaped steel beam.

[0003] The connections between square steel pipe columns and H-shaped steel beams can be broadly classified into internal diaphragm type using an internal diaphragm, through diaphragm type using a through diaphragm, and external diaphragm type using an external diaphragm.

[0004] Of these, the through diaphragm type is most commonly used for the connection between a square steel pipe column and an H-shaped steel beam. Figures 10(a) and 10(b) show a perspective view and a plan view of a connection between a square steel pipe column 81 and an H-shaped steel beam 82 using the through diaphragm type. Figure 11 shows a vertical cross-sectional view of the main parts of a connection between a square steel pipe column 81 and an H-shaped steel beam 82 using the through diaphragm type.

[0005] 10(a) and 10(b), and 11, in a through diaphragm type joint between a square steel pipe column 81 and an H-shaped steel beam 82, a through diaphragm 85 is provided so as to penetrate the cross section of the square steel pipe column 81. For this reason, the assembly of a through diaphragm type joint between a square steel pipe column and an H-shaped steel beam is performed by cutting the square steel pipe column 81 at the position where the through diaphragm 85 is to be provided, inserting the through diaphragm 85 into the cut position, and welding the square steel pipe column 81 and the through diaphragm 85 together.

[0006] 11, the weld 86 between the square steel pipe column 81 and the through diaphragm 85 is made by full penetration welding, so that the performance of the square steel pipe column 81 is ensured even if the through diaphragm 85 is provided so as to penetrate the cross section of the square steel pipe column 81. The welding between the square steel pipe column 81 and the through diaphragm 85 is performed in a steel frame manufacturing factory or the like by applying automatic welding such as robot welding, which has high welding efficiency, so that the weld 86 can be made high quality and stable.

[0007] However, as described above, the assembly of the joint between the square steel pipe column and the H-shaped steel beam using the through diaphragm type is performed by cutting the square steel pipe column 81 at the position where the through diaphragm 85 is to be provided, inserting the through diaphragm 85 at the cut position, and welding the square steel pipe column 81 and the through diaphragm 85 together. Therefore, it takes time and effort to cut the square steel pipe column 81 and to prepare the groove for full penetration welding of the square steel pipe column 81 to the through diaphragm 85, and the amount of welding tends to be large. In addition, high skill is required to ensure the accuracy of the alignment of the square steel pipe column 81 to be joined above and below the through diaphragm 85.

[0008] Furthermore, a building is designed with the through diaphragm 85 provided so as to penetrate the cross section of the square steel pipe column 81 as constituting a part of the square steel pipe column 81. As a prerequisite for this design, it is necessary to use a welding material having a strength equal to or greater than that of the square steel pipe column 81 for the welded portion 86 between the square steel pipe column 81 and the through diaphragm 85, which tends to increase material costs and construction load. For example, when a high-strength steel material is used as the square steel pipe column 81, it becomes necessary to use a high-strength welding material having a strength class equal to or greater than that of the square steel pipe column 81 for the welded portion 86 between the square steel pipe column 81 and the through diaphragm 85.

[0009] 12(a) and 12(b) show a perspective view and a plan view of a joint between a square steel pipe column 81 and an H-shaped steel beam 82 by the internal diaphragm type. As shown in FIG. 12(a) and FIG. 12(b), in the joint between a square steel pipe column 81 and an H-shaped steel beam 82 by the internal diaphragm type, the internal diaphragm 84 is provided inside the square steel pipe column 81 without penetrating the cross section of the square steel pipe column 81. Therefore, the strength of the welding material used in the weld between the square steel pipe column 81 and the internal diaphragm 84 does not affect the performance of the square steel pipe column 81. In other words, it is not necessary to use a welding material having a strength equal to or greater than the strength of the square steel pipe column 81 for the weld between the square steel pipe column 81 and the internal diaphragm 84, and it is sufficient to use a welding material having a strength equal to or greater than the strength of the H-shaped steel beam 82.

[0010] However, since the welding between the square steel pipe column 81 and the inner diaphragm 84 is performed by dropping the inner diaphragm 84 into the inside of the square steel pipe column 81, it is extremely difficult to control the assembly accuracy and welding conditions of the inner diaphragm 84 and backing metal, as well as to inspect and repair the welded joints.

[0011] 13(a) and 13(b) show a perspective view and a plan view of a joint between a square steel pipe column 81 and an H-shaped steel beam 82 by the external diaphragm type. As shown in FIG. 13(a) and FIG. 13(b), in the joint between a square steel pipe column 81 and an H-shaped steel beam 82 by the external diaphragm type, the external diaphragm 83 is provided on the outside of the square steel pipe column 81 without penetrating the cross section of the square steel pipe column 81. Therefore, as in the case of the internal diaphragm type, the strength of the welding material used in the weld between the square steel pipe column 81 and the external diaphragm 83 does not affect the performance of the square steel pipe column 81. In other words, for the weld between the square steel pipe column 81 and the external diaphragm 83, it is not necessary to use a welding material having a strength equal to or greater than the strength of the square steel pipe column 81, and it is sufficient to use a welding material having a strength equal to or greater than the strength of the H-shaped steel beam 82.

[0012] 13(a) and 13(b), in the joint between a square steel pipe column 81 and an H-shaped steel beam 82 using the external diaphragm type, the square steel pipe column 81 and the external diaphragm 83 are welded from the outside of the square steel pipe column 81. This makes it easy to attach the external diaphragm 83 to the square steel pipe column 81, and ensures the assembly accuracy of the components. Furthermore, since no diaphragm is inserted inside the square steel pipe column 81, it is also easy to work with when filling the inside of the square steel pipe column 81 with concrete.

[0013] 14 to 16 show longitudinal cross-sectional views of the main parts of a joint between a square steel pipe column 81 and an H-shaped steel beam 82 using an external diaphragm. Fig. 14 shows an example in which a weld 87 between the square steel pipe column 81 and the external diaphragm 83 is fillet welded. Fig. 15 shows an example in which a weld 88 between the square steel pipe column 81 and the external diaphragm 83 is fully welded. Fig. 16 shows an example in which a weld 89 between the square steel pipe column 81 and the external diaphragm 83 is partially welded.

[0014] The square steel pipe column 81 and the outer diaphragm 83 are generally joined by fillet welding as shown in Fig. 14, or by full penetration welding or partial penetration welding after groove preparation on the outer diaphragm 83 as shown in Fig. 15 and Fig. 16. Semi-automatic gas shielded arc welding or the like is applied for these fillet welding, full penetration welding and partial penetration welding, but compared with automatic welding such as robot welding adopted for the through diaphragm type, the manufacturing efficiency tends to be lower.

[0015] 13(a) and 13(b), the corners 81c of the cold-formed square steel pipe column 81 have a radius, so that it is more difficult to weld the outer diaphragm 83 than to the flat portion of the side surface of the square steel pipe column 81. In particular, when joining the outer diaphragm 83 to the square steel pipe column 81 by full penetration welding or partial penetration welding, it is difficult to perform groove preparation on the outer diaphragm 83 attached to the vicinity of the corners 81c of the square steel pipe column 81.

[0016] 13(b), in a joint between a square steel pipe column 81 and an H-shaped steel beam 82 using an external diaphragm type, the protruding width 83h of the external diaphragm 83 from the side surface of the square steel pipe column 81 is often made large in order to ensure the strength of the column-beam joint. Therefore, when a square steel pipe column 81 with an external diaphragm 83 attached is manufactured in a steel frame manufacturing factory and transported to a construction site, if the protruding width 83h of the external diaphragm 83 is large, the number of square steel pipe columns 81 that can be loaded onto a transport vehicle at one time is limited, and transport efficiency is likely to deteriorate.

[0017] Therefore, Patent Documents 1 and 2 propose an external diaphragm that can ensure the strength of the column-beam joint while reducing the protruding width of the external diaphragm, and a column-beam joint structure using the same.

[0018] Specifically, Patent Document 1 proposes using a sleeve-shaped external diaphragm formed by bending flat steel outward to fit the outer peripheral surface of a square steel pipe column, thereby reducing the planar shape compared to conventional external diaphragms.

[0019] In addition, Patent Document 2 proposes combining four L-shaped steel pieces to form an outer diaphragm, and using a material with a large plate thickness for the L-shaped steel pieces to reduce the dimensions of the outer diaphragm. The L-shaped steel pieces are joined together by fillet welding or partial penetration welding on the front and back surfaces. [Prior art documents] [Patent documents]

[0020] [Patent Document 1] JP 2006-002351 A [Patent Document 2] JP 2016-108868 A Summary of the Invention [Problem to be solved by the invention]

[0021] Here, in order to ensure the quality of the welded joint between the square steel pipe column and the outer diaphragm, it is necessary to ensure the root spacing between the square steel pipe column and the outer diaphragm with appropriate accuracy. If the root spacing is too small, welding defects are likely to occur, and if the root spacing is too large, the amount of welding increases and workability deteriorates. However, in Patent Document 1, there is a problem that it is difficult to ensure the dimensional accuracy when manufacturing the outer diaphragm and the assembly accuracy when attaching the outer diaphragm to the square steel pipe column because localized residual stress occurs in the flat steel when bending the flat steel out of the plane.

[0022] In addition, in Patent Document 1 and Patent Document 2, it is assumed that the square steel pipe column and the outer diaphragm are joined by fillet welding using gas shielded arc welding, or by partial penetration welding after groove preparation on the outer diaphragm. Therefore, there is a problem that the manufacturing efficiency is likely to be low compared to automatic welding such as robot welding adopted for the through diaphragm type.

[0023] The present invention has been made to solve such problems, and aims to provide a connection structure between a square steel pipe column and an H-shaped steel beam, and a manufacturing method for the connection structure, which has high manufacturing efficiency and can reliably ensure assembly precision between the components. [Means for solving the problem]

[0024] In order to solve the above problems, the present invention has the following features.

[0025] [1] A connection structure between a square steel pipe column and an H-shaped steel beam, in which an H-shaped steel beam is connected to a square steel pipe column via an external diaphragm, in which a welding hole surrounded by a backing metal is provided between the side of the square steel pipe column and the end face of the external diaphragm, and the square steel pipe column and the external diaphragm are connected by a weld formed by filling the welding hole with molten metal by electroslag welding.

[0026] [2] The connection structure of a square steel pipe column and an H-shaped steel beam described in [1], wherein the external diaphragm is extended to the corner of the square steel pipe column, the corner of the square steel pipe column has a radius, and a filler material made of a steel plate is provided in the gap between the external diaphragm and the corner of the square steel pipe column due to the radius, and the welding hole extends linearly from the side of the square steel pipe column to the side of the filler material.

[0027] [3] A joint structure for a square steel pipe column and an H-shaped steel beam described in [1] or [2], in which a partition made of a steel piece is provided inside the welding hole so that the welding hole is divided into two or more holes in the thickness direction of the outer diaphragm.

[0028] [4] A connection structure between a square steel pipe column and an H-shaped steel beam described in [1] or [2], wherein the yield strength of the external diaphragm is greater than the yield strength of the flange of the H-shaped steel beam.

[0029] [5] A connection structure between a square steel pipe column and an H-shaped steel beam as described in [3], wherein the yield strength of the external diaphragm is greater than the yield strength of the flange of the H-shaped steel beam.

[0030] [6] A manufacturing method for a connection structure between a square steel pipe column and an H-shaped steel beam, in which an H-shaped steel beam is connected to a square steel pipe column via an external diaphragm, the method comprising: forming a welding hole by surrounding the space between the side of the square steel pipe column and the end face of the external diaphragm with a backing metal; filling the welding hole with molten metal by electroslag welding with a heat input of 100 to 1500 kJ / cm to form a weld, thereby joining the square steel pipe column and the external diaphragm.

[0031] [7] A manufacturing method for a connection structure between a square steel pipe column and an H-shaped steel beam described in [6], in which the external diaphragm is extended to the corner of the square steel pipe column, and the corner of the square steel pipe column has a radius, and a filler material made of a steel plate is provided in the gap between the external diaphragm and the square steel pipe column caused by the radius, so that the welding hole is extended in a straight line from the side of the square steel pipe column to the side of the filler material.

[0032] [8] A manufacturing method for a joint structure between a square steel pipe column and an H-shaped steel beam described in [6] or [7], in which a partition made of a steel piece is provided inside the welding hole so that the welding hole is divided into two or more holes in the thickness direction of the outer diaphragm.

[0033] [9] A manufacturing method for a joint structure between a square steel pipe column and an H-shaped steel beam described in [6] or [7], wherein the yield strength of the external diaphragm is greater than the yield strength of the flange of the H-shaped steel beam.

[0034]

[10] A manufacturing method for a joint structure between a square steel pipe column and an H-shaped steel beam described in [8], wherein the yield strength of the external diaphragm is greater than the yield strength of the flange of the H-shaped steel beam. Effect of the Invention

[0035] In the joint structure between a square steel pipe column and an H-shaped steel beam and the manufacturing method of the joint structure according to the present invention, the square steel pipe column and the external diaphragm are joined by electroslag welding. Electroslag welding is a welding method that applies a large heat input of up to several million J / cm, and is extremely efficient compared to manual or semi-automatic gas-shielded arc welding. Therefore, the manufacturing efficiency can be significantly improved compared to the joint structure between a square steel pipe column and an H-shaped steel beam using a general external diaphragm type that is joined by gas-shielded arc welding.

[0036] In addition, in the joint structure between a square steel pipe column and an H-shaped steel beam and the manufacturing method of the joint structure according to the present invention, the electroslag welding between the square steel pipe column and the outer diaphragm is performed from the outside of the square steel pipe column, so that the assembly precision of the root clearance between the side surface of the square steel pipe column and the end face of the outer diaphragm, the backing metal, etc. can be reliably ensured. [Brief description of the drawings]

[0037] [Figure 1] FIG. 1 is a plan view of a joint structure between a square steel pipe column and an H-shaped steel beam according to a first embodiment of the present invention. [Diagram 2]FIG. 2 is a vertical cross-sectional view showing a main part of a joint structure between a square steel pipe column and an H-shaped steel beam according to the first embodiment of the present invention. [Diagram 3] FIG. 3 is a vertical cross-sectional view showing a main part of a joint structure between a square steel pipe column and an H-shaped steel beam according to the first embodiment of the present invention. [Figure 4] FIG. 4 is a diagram showing the shape of a steel plate in a joint structure of a square steel pipe column and an H-shaped steel beam of the present invention. [Diagram 5] 5(a) to 5(c) are diagrams showing a manufacturing procedure for the joint structure of the present invention between a square steel pipe column and an H-shaped steel beam. [Figure 6] FIG. 6 is a plan view showing an example of the shape of an exterior diaphragm in a joint structure of a square steel pipe column and an H-shaped steel beam of the present invention. [Figure 7] 7(a) and 7(b) are plan views showing other examples of the shape of the exterior diaphragm in the joint structure of the present invention between a square steel pipe column and an H-shaped steel beam. [Figure 8] FIG. 8 is a vertical cross-sectional view showing a main part of a joint structure between a square steel pipe column and an H-shaped steel beam according to a second embodiment of the present invention. [Figure 9] FIG. 9 is a vertical cross-sectional view showing a main part of a joint structure between a square steel pipe column and an H-shaped steel beam according to a second embodiment of the present invention. [Figure 10] 10(a) and 10(b) are a perspective view and a plan view showing a through diaphragm type joint between a square steel pipe column and an H-shaped steel beam. [Figure 11] FIG. 11 is a vertical cross-sectional view showing a main part of a through diaphragm type joint between a square steel pipe column and an H-shaped steel beam. [Figure 12] 12(a) and 12(b) are a perspective view and a plan view showing a joint between a square steel pipe column and an H-shaped steel beam using an internal diaphragm type. [Figure 13] 13(a) and 13(b) are a perspective view and a plan view showing a joint between a square steel pipe column and an H-shaped steel beam using an external diaphragm type. [Figure 14] FIG. 14 is a vertical cross-sectional view showing a main part of a joint between a square steel pipe column and an H-shaped steel beam using an external diaphragm type. [Figure 15]FIG. 15 is a vertical cross-sectional view showing a main part of a joint between a square steel pipe column and an H-shaped steel beam using an external diaphragm type. [Figure 16] FIG. 16 is a vertical cross-sectional view showing a main part of a joint between a square steel pipe column and an H-shaped steel beam using an external diaphragm type. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0038] Hereinafter, with reference to the drawings, an embodiment of a joint structure between a square steel pipe column and an H-shaped steel beam and a manufacturing method of the joint structure of the present invention will be described in detail. First Embodiment Fig. 1 shows a plan view of a joint structure between a square steel pipe column and an H-shaped steel beam according to a first embodiment of the present invention. Fig. 2 and Fig. 3 show longitudinal sectional views of the main parts of the joint structure between a square steel pipe column and an H-shaped steel beam according to the first embodiment of the present invention.

[0039] As shown in Fig. 1 to Fig. 3, the joint structure between a square steel pipe column and an H-shaped steel beam in this embodiment is one in which an H-shaped steel beam 2 is joined to a square steel pipe column 1 via an outer diaphragm 3. Specifically, as shown in Fig. 2, a welding hole 32 surrounded by a backing metal 31 is provided between the side surface of the square steel pipe column 1 and the end face of the outer diaphragm 3. Then, as shown in Fig. 3, the square steel pipe column 1 and the outer diaphragm 3 are joined to each other by a weld 5 formed by filling the welding hole 32 with molten metal by electroslag welding.

[0040] As shown in FIG. 1, the cross-sectional shape of the electroslag welding hole 32 is rectangular, similar to the electroslag welding hole between the skin plate and the inner diaphragm at the joint between the box section column and the H-shaped steel beam by the inner diaphragm type.

[0041] In the joint structure of the square steel pipe column and the H-shaped steel beam of this embodiment, the external diaphragm 3 is extended to the corner 1c of the square steel pipe column 1 and beyond the corner 1c, as shown in Fig. 1. The corner 1c of the square steel pipe column 1 has a radius, and in the gap between the corner 1c and the external diaphragm 3 caused by this radius, a filler 4 made of a steel plate that matches the shape of the corner 1c is provided, as shown in Fig. 4.

[0042] The backing metal 31 and the welding hole 32 extend linearly from the side surface of the square steel pipe column 1 to the side surface of the filler material 4. The backing metal 31 and the welding hole 32 extending in the horizontal direction of the paper in FIG. 1 extend linearly from the side surface of the square steel pipe column 1 to the side surface of the filler material 4, and further to between the outer diaphragms 3. That is, the welding hole 32 is formed on the side surface of the square steel pipe column 1 by being surrounded by the square steel pipe column 1, the outer diaphragm 3, and the backing metal 31, and is formed at the corner 1c of the square steel pipe column 1 by being surrounded by the filler material 4, the outer diaphragm 3, and the backing metal 31. Both ends of the welding hole 32 extending in the horizontal direction of the paper in FIG. 1 are formed by being surrounded by the spaces between the outer diaphragms 3 and the backing metal 31. With this configuration, it is possible to join the external diaphragm 3 by electroslag welding up to the corner 1c of the square steel pipe column 1, and even beyond the corner 1c to the space between the external diaphragms 3, over a length equal to or greater than the outer diameter of the square steel pipe column 1.

[0043] For the H-shaped steel beam 2 connected to the square steel pipe column 1, either a roll-formed H-shaped steel or a welded assembled H-shaped steel can be used.

[0044] In addition, the backing plate 31 may be made of the same steel material as that used in electroslag welding between the skin plate and the inner diaphragm at the joint between the box section column and the H-shaped steel beam by the inner diaphragm type.

[0045] The filler 4 attached to the corner 1c of the square steel pipe column 1 is made of a steel plate having a strength equal to or greater than that of the outer diaphragm 3. In order to facilitate electroslag welding, the plate thickness of the filler 4 is set to t d Equal to or greater than the above.

[0046] In addition, in order to prevent the molten metal from leaking out of the welding hole 32 during electroslag welding, the filler 4 is arranged to be in contact with the square steel pipe column 1 at the start position of the radius of the corner 1c of the square steel pipe column 1. In contrast, at the center position of the radius of the corner 1c of the square steel pipe column 1, the square steel pipe column 1 and the filler 4 do not necessarily need to be in contact with each other, and there may be a gap between the filler 4 and the corner 1c of the square steel pipe column 1. For example, FIG. 4 shows an example in which the side surface of the filler 4 facing the corner 1c of the square steel pipe column 1 is formed into a curved shape that matches the radius shape of the corner 1c, but a flat surface may be included in part of the side surface of the filler 4 facing the corner 1c of the square steel pipe column 1.

[0047] In addition, it is preferable that the yield strength of the outer diaphragm 3 is greater than the yield strength of the flange of the H-shaped steel beam 2 attached to the outer diaphragm 3. In this way, the protruding width h of the outer diaphragm 3 shown in FIG. 1 can be increased without reducing the strength of the beam-column joint against the stress acting on the side surface of the square steel pipe column 1 from the flange 21 of the H-shaped steel beam 2 during an earthquake or the like. d When the square steel pipe column 1 with the outer diaphragm 3 attached is manufactured in a steel frame manufacturing factory and transported to a construction site, the protruding width h of the outer diaphragm 3 can be reduced. d This makes it difficult for the transportation efficiency of the square steel pipe column 1 to be impaired.

[0048] 5(a) to 5(c) show a manufacturing procedure for the joint structure of a square steel pipe column and an H-shaped steel beam of this embodiment.

[0049] First, as shown in Fig. 5(a), a filler material 4 is attached to the corner 1c of the square steel pipe column 1. When attaching the filler material 4 to the square steel pipe column 1, it is preferable to avoid direct welding to the corner 1c of the square steel pipe column 1, and to weld the tip of the filler material 4 in the plate thickness direction to the radius start position of the corner 1c of the square steel pipe column 1. In this way, it is possible to suppress deterioration of mechanical performance caused by welding in the corner 1c of the square steel pipe column 1 manufactured by cold roll-formed square steel pipes or cold press forming.

[0050] Next, as shown in Fig. 5(b), with the square steel pipe column 1 laid on its side, the outer diaphragm 3 and the backing metal 31 are temporarily attached to the two opposing side surfaces, and a welding hole 32 is provided in a straight line from the side surface of the square steel pipe column 1 to the side surface of the filling material 4. Then, the welding hole 32 is filled with molten metal by electroslag welding to form a weld 5, and the square steel pipe column 1 and the outer diaphragm 3 are joined together.

[0051] Furthermore, the square steel pipe column 1 is rotated by 90°. Then, as shown in Fig. 5(c), the outer diaphragm 3 and the backing metal 31 are temporarily attached to the remaining two side surfaces of the square steel pipe column 1, and welding holes 32 are provided linearly from the side surfaces of the square steel pipe column 1 to the side surfaces of the filling material 4 and further to the spaces between the outer diaphragms 3. Then, the welding holes 32 are filled with molten metal by electroslag welding to form welds 5, and the square steel pipe column 1 and the outer diaphragms 3 are joined together.

[0052] In the above-mentioned example of the manufacturing procedure, the filler 4 is first attached to the corner 1c of the square steel pipe column 1, but a member in which the filler 4, the outer diaphragm 3, and the backing metal 31 are integrally combined may be manufactured in advance, and this member may be attached to the square steel pipe column 1. In this way, the manufacturing procedure of the joint structure of the square steel pipe column and the H-shaped steel beam of this embodiment can be simplified.

[0053] In the joint structure of a square steel pipe column and an H-shaped steel beam of this embodiment, since the outer diaphragm 3 is attached to the outside of the square steel pipe column 1, electroslag welding between the square steel pipe column 1 and the outer diaphragm 3 is performed from the outside of the square steel pipe column 1. Therefore, the assembly precision of the root clearance G between the surface of the square steel pipe column 1 and the end face of the outer diaphragm 3, the backing metal 31, etc. can be reliably ensured.

[0054] In addition, the root spacing G between the surface of the square steel pipe column 1 and the end face of the external diaphragm 3 in the joint structure of a square steel pipe column and an H-shaped steel beam in this embodiment can be set to an appropriate dimension, similar to the root spacing between the inner surface of the box section column and the end face of the internal diaphragm at the joint between a box section column and an H-shaped steel beam using the internal diaphragm type.

[0055] In addition, in the joint structure between a square steel pipe column and an H-shaped steel beam of this embodiment, the square steel pipe column 1 and the outer diaphragm 3 are joined by electroslag welding. Therefore, compared with the joint structure between a square steel pipe column and an H-shaped steel beam using a general outer diaphragm type joined by gas shielded arc welding, the manufacturing efficiency can be significantly improved.

[0056] 6(a), 6(b), 7(a) and 7(b) show modified shapes of the outer diaphragm 3 in the joint structure of a square steel pipe column and an H-shaped steel beam of this embodiment.

[0057] 6(a) and 6(b) are modified examples in which the width of the outer diaphragm 3A is reduced from the width of the outer diaphragm 3 shown in FIG. 1. In the example shown in FIG. 1, the filler material 4 is attached to the corner 1c of the square steel pipe column 1, so that the outer diaphragm 3 having a width equal to or larger than the outer diameter of the square steel pipe column 1 can be joined by electroslag welding. In contrast, in this modified example, it is not necessary to attach the filler material 4 to the corner 1c of the square steel pipe column 1. In this modified example, the outer diaphragm 3 can be extended to a position that does not overlap the radius of the corner 1c of the square steel pipe column 1. The square steel pipe column 1 and the outer diaphragm 3 are joined by a weld 5 formed by filling the welding hole 32 with molten metal by electroslag welding, as in the example shown in FIGS. 1 to 3. Also, as shown in Figures 3(a) and 3(b), external diaphragms 3 are joined to 1 to 4 of the four side surfaces of the square steel pipe column 1 depending on the number of H-shaped steel beams 2 attached to the square steel pipe column 1.

[0058] Fig. 4(a) shows a modified example in which a steel plate formed into a polygonal shape is used as the outer diaphragm 3B. Fig. 4(b) shows a modified example in which a part of the planar shape of the outer diaphragm 3C has a circular arc. As shown in Fig. 4(b), when a part of the planar shape of the outer diaphragm 3C has a circular arc, stress can be smoothly transmitted from the flange 21 of the H-shaped steel beam 2 to the side of the square steel pipe column 1 via the outer diaphragm. This is preferable because it can suppress the occurrence of cracks or breaks in the outer diaphragm 3.

[0059] In addition, the manufacturing method of the joint structure between a square steel pipe column and an H-shaped steel beam in this embodiment is realized by performing electroslag welding so that the heat input is 100 to 1500 kJ / cm when manufacturing the joint structure between the above-mentioned square steel pipe column 1 and the H-shaped steel beam 2. Second Embodiment 8 and 9 show vertical cross-sectional views of essential parts of a joint structure between a square steel pipe column and an H-shaped steel beam according to a second embodiment of the present invention.

[0060] As shown in Figs. 8 and 9, in the joint structure of the square steel pipe column and the H-shaped steel beam of this embodiment, the plate thickness of the flange 21 of the H-shaped steel beam 2 and the outer diaphragm 3 is larger than that of the joint structure of the square steel pipe column and the H-shaped steel beam of the first embodiment. When electroslag welding with a large heat input is applied to general steel materials for architectural structures, the toughness of the welded portion 5 by electroslag welding is reduced, and brittle fracture is likely to occur in the welded portion 5 due to the stress transmitted from the flange 21 of the H-shaped steel beam 2 to the outer diaphragm 3 during an earthquake. In particular, when the plate thickness of the outer diaphragm 3 is large as in this embodiment, the amount of heat input required to ensure penetration of the weld metal into the members around the welding hole during electroslag welding increases, which is likely to cause a significant decrease in the toughness of the welded portion 5.

[0061] Therefore, in the joint structure of the square steel pipe column and the H-shaped steel beam of this embodiment, as shown in Fig. 8 and Fig. 9, a partition wall 33 made of a steel piece is provided inside a welding hole surrounded by the surface of the square steel pipe column 1, the end face of the outer diaphragm 3, and the backing metal 31. As a result, the welding hole surrounded by the surface of the square steel pipe column 1, the end face of the outer diaphragm 3, and the backing metal 31 is divided into two welding holes 34, 35 in the plate thickness direction of the outer diaphragm 3. In this way, the width w of each welding hole 34, 35 in the plate thickness direction of the outer diaphragm 3 is 1 , w 2 That is, even if the plate thickness of the flange 21 of the H-shaped steel beam 2 or the outer diaphragm 3 is large, the amount of heat input required to ensure penetration of the weld metal into the members around the welding hole during electroslag welding can be reduced, and a significant decrease in the toughness of the welded portion 5 can be suppressed.

[0062] The above describes embodiments of the joint structure between a square steel pipe column and an H-shaped steel beam and the manufacturing method of the joint structure of the present invention. However, the specific configuration of the present invention is not limited to the above-mentioned embodiments, and design changes are possible within the scope of the gist of the present invention.

[0063] For example, in FIG. 8 and FIG. 9, the width w of the welding holes 34, 35 1 , w2 The width w of the welding holes 34 and 35 is the same. 1 , w 2 8 and 9 show an example in which the welding hole surrounded by the side surface of the square steel pipe column 1, the end face of the outer diaphragm 3, and the backing metal 31 is divided into two welding holes 34, 35, but the welding hole may be divided into three or more welding holes in the thickness direction of the outer diaphragm 3. It is preferable to appropriately set the number of divisions and width of the welding hole in consideration of the type and dimensions of the steel material used, the welding conditions of the electroslag welding, etc., so that brittle fracture of the welded part 5 can be effectively suppressed against stress transmitted from the flange 21 of the H-shaped steel beam 2 to the outer diaphragm 3 during an earthquake or the like. EXAMPLES

[0064] In the second embodiment of the joint structure between a square steel pipe column and an H-shaped steel beam, a partition wall 33 was provided inside the welding hole to divide the outer diaphragm 3 into two welding holes 34, 35 in the thickness direction, thereby verifying how much the heat input of electroslag welding could be reduced.

[0065] First, calculation examples No. 1 to 3 were set based on the joint structure of the square steel pipe column and the H-shaped steel beam of the first embodiment shown in Fig. 2 and Fig. 3. Table 1 shows the outer diameter D of the square steel pipe column 1 in each of calculation examples No. 1 to 3. c and wall thickness t c , the protruding width h of the outer diaphragm 3 d and plate thickness t d , the root spacing G and width w of the welding hole 32 0 Shows.

[0066] [Table 1]

[0067] As shown in Table 1, in calculation examples No. 1 to 3, the outer diameter D of the square steel pipe column 1 c The outer diameter D of the square steel pipe column 1 was changed to 500 mm, 800 mm, and 1000 mm. cIn calculation examples 1 to 3, the wall thickness t of the square steel pipe column 1 is c , and the protruding width h of the outer diaphragm 3 d and plate thickness t d The root spacing G of the welding holes 32 was set to 23 mm in all of the calculation examples Nos. 1 to 3.

[0068] The amount of heat input required to ensure penetration of the weld metal into the members surrounding the weld hole 32 during electroslag welding varies depending on the dimensions of the members surrounding the weld hole 32. Therefore, in this embodiment, as a calculation standard, the heat input in calculation example No. 1 was assumed to be 300 kJ / cm. The calculation of the amount of heat input in calculation examples No. 2 and No. 3 was performed using the cross-sectional area of ​​the weld hole 32 in calculation examples No. 2 and No. 3 relative to calculation example No. 1, the wall thickness t of the square steel pipe column 1, and the cross-sectional area t of the weld hole 32 in calculation examples No. 2 and No. 3 relative to calculation example No. 1. c , the protruding width h of the outer diaphragm 3 d and plate thickness t d The calculation results are shown in Table 1.

[0069] As can be seen from calculation examples No. 1 to 3 in Table 1, the thickness t d When the thickness t of the outer diaphragm 3 is small, the heat input of the electroslag welding is kept small, and the toughness of the welded portion 5 is not significantly deteriorated. d As this increases, the heat input in electroslag welding also increases, which tends to cause a significant decrease in the toughness of the welded portion 5.

[0070] Next, a calculation example No. 3A was set based on the joint structure of the square steel pipe column and the H-shaped steel beam of the second embodiment shown in Figures 8 and 9, and the heat input of the electroslag welding was calculated. c and wall thickness t c , the protruding width h of the outer diaphragm 3 d and plate thickness t d , the root spacing G and width w of the welding holes 34, 35 1 , w 2Calculation example No. 3A is an example in which a partition wall 33 is provided inside the welding hole 32 of calculation example No. 3 shown in Table 1, and the partition wall 33 is divided into two welding holes 34 and 35 in the thickness direction of the outer diaphragm 3. The thickness B of the partition wall 33 in calculation example No. 3A is 15 mm, and the width w of the welding holes 34 and 35 is 15 mm. 1 , w 2 are assumed to be 22.5 mm each.

[0071] [Table 2]

[0072] Then, the heat input due to electroslag welding was calculated for calculation example No. 3A in the same manner as calculation examples No. 1 to 3. The calculation results are also shown in Table 2.

[0073] As can be seen from calculation example No. 3A in Table 2, by dividing the welding hole for electroslag welding into two welding holes 34, 35 by partition 33 and performing electroslag welding on each of welding holes 34, 35, the heat input is reduced to the same level as calculation example No. 1 in Table 1. In other words, it was confirmed that by dividing the welding hole for electroslag welding into two welding holes 34, 35 by partition 33 and performing electroslag welding on each of welding holes 34, 35, a significant decrease in toughness of welded portion 5 can be suppressed. [Explanation of symbols]

[0074] 1 Square steel pipe column 1c Corner 2 H-shaped steel beam 21 Flange 22 Web 3, 3A~3C Outer diaphragm 31 Backing 32, 34, 35 Welding holes 33 Bulkhead 4 Filling material w 0 ~w 2 Welding hole width 5 Welding Dc Outside diameter of square steel pipe column t c Square steel pipe column thickness t d Outer diaphragm thickness h d Outer diaphragm protrusion width G Root Spacing B Thickness of bulkhead 81 Square steel pipe column 81c Corner 82 H-shaped steel beam 821 Flange 83 Outer diaphragm 83h Outer diaphragm protrusion width 84 Inner diaphragm 85 through diaphragm 86~89 Welded parts

Claims

1. A joint structure between a square steel pipe column and an H-shaped steel beam, in which an H-shaped steel beam is joined to a square steel pipe column via an external diaphragm, A joining structure between a square steel pipe column and an H-shaped steel beam, in which a welding hole surrounded by a metal is provided between the side surface of the square steel pipe column and the end face of the external diaphragm, and the square steel pipe column and the external diaphragm are joined by a weld formed by filling the welding hole with molten metal by electroslag welding.

2. The outer diaphragm is extended to the corner of the square steel pipe column, The corners of the square steel pipe column have a radius, and a filler made of a steel plate is provided in the gap between the corners and the outer diaphragm caused by the radius, The connection structure between a square steel pipe column and an H-shaped steel beam as described in claim 1, wherein the welding hole extends linearly from the side of the square steel pipe column to the side of the filling material.

3. The joining structure of a square steel pipe column and an H-shaped steel beam as described in claim 1 or 2, wherein a partition made of a steel piece is provided inside the welding hole so that the welding hole is divided into two or more holes in the plate thickness direction of the outer diaphragm.

4. The connection structure between a square steel pipe column and an H-shaped steel beam as described in claim 1 or 2, wherein the yield strength of the outer diaphragm is greater than the yield strength of the flange of the H-shaped steel beam.

5. The connection structure between a square steel pipe column and an H-shaped steel beam as described in claim 3, wherein the yield strength of the outer diaphragm is greater than the yield strength of the flange of the H-shaped steel beam.

6. A manufacturing method for a joint structure between a square steel pipe column and an H-shaped steel beam, in which an H-shaped steel beam is joined to a square steel pipe column via an external diaphragm, A manufacturing method for a joint structure of a square steel pipe column and an H-shaped steel beam, comprising: providing a welding hole by surrounding the area between the side surface of the square steel pipe column and the end face of the outer diaphragm with a metal strip; filling the welding hole with molten metal by electroslag welding with a heat input of 100 to 1500 kJ / cm to form a weld, thereby joining the square steel pipe column and the outer diaphragm.

7. The outer diaphragm is extended to a corner of the square steel pipe column, and the corner of the square steel pipe column has a radius, The manufacturing method of the joint structure of a square steel pipe column and an H-shaped steel beam as described in claim 6, wherein a filler material made of a steel plate is provided in the gap created between the outer diaphragm by the curve, so that the welding hole is extended linearly from the side of the square steel pipe column to the side of the filler material.

8. The method for manufacturing a joint structure of a square steel pipe column and an H-shaped steel beam as described in claim 6 or 7, wherein a partition wall made of a steel piece is provided inside the welding hole so that the welding hole is divided into two or more holes in the plate thickness direction of the outer diaphragm.

9. The method for manufacturing a joint structure between a square steel pipe column and an H-shaped steel beam according to claim 6 or 7, wherein the yield strength of the outer diaphragm is greater than the yield strength of a flange of the H-shaped steel beam.

10. The manufacturing method of a joint structure between a square steel pipe column and an H-shaped steel beam according to claim 8, wherein the yield strength of the outer diaphragm is greater than the yield strength of the flange of the H-shaped steel beam.

Images