Joint structure at beam step

Abstract

To reduce the welding volume and steel frame volume.SOLUTION: A joint structure at a beam step is applied to a column-beam joint in a column RC-beam S construction, and comprises a first connecting beam member 10 and a second connecting beam member 20 provided above the first connecting beam member 10, connected in a stepped configuration. The first connecting beam member 10 is formed from an H-shaped steel. The second connecting beam member 20 is formed from the H-shaped steel. The second connecting beam member 20 has a flange missing portion 24 where a part of a second lower flange 21 is missing. The joint structure comprises a first welded portion 31, where a lower end portion 25 of a second web 23 at the flange missing portion 24 is welded to an upper surface of a first upper flange 12, and a second welded portion 32, where an end portion of the first upper flange 12 is welded to an end portion of the second lower flange 21 adjacent to the flange missing portion 24.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a joint structure at a beam step. [Background technology]

[0002] One structural style for buildings is RC column-S beam construction, where the columns are made of reinforced concrete (RC) and the beams are made of steel (S). RC column-S beam construction is a structural style that uses concrete, which has a high resistance to compressive forces, and H-shaped steel beams, which are H-shaped steel frames with a cross section that efficiently resist shear forces and bending moments, in the right places.

[0003] Patent Document 1 discloses a joint structure for a column-beam joint in a reinforced concrete column-steel beam construction. Furthermore, conventionally, some column-beam joints in reinforced concrete column-steel beam construction have been provided with a beam step portion where the first beam material and the second beam material are connected in a stepped manner.

[0004] An example of such a joint structure at a beam step is shown in Figure 4. As shown in FIG. 4, a column 190 is provided with a column 110 made of H-shaped steel. A lower flange 141 and an upper flange 142 at one end of a first beam 140 are fully penetrated welded to the outer surface of one flange 111 of the post 110. A lower flange 151 and an upper flange 152 at one end of a second beam 150 are fully penetrated welded to the outer surface of the other flange 112 of the post 110. The second beam 150 is positioned higher than the first beam 140. The first beam 140 and the second beam 150 are connected in a stepped manner via the post 110.

[0005] Diaphragms 114, 115 are provided between the inner surfaces of the flanges 111, 112 of the column 110. The diaphragms 114, 115 are located at the same height as the lower flange 141 and the upper flange 142, respectively. The diaphragms 114, 115 are fully welded to the inner surfaces of the flanges 111, 112 and fillet welded to the web 113 of the column 110.

[0006] Diaphragms 116, 117 are provided between the inner surfaces of the flanges 111, 112 of the column 110. The diaphragms 116, 117 are located at the same height as the lower flange 151 and the upper flange 152, respectively. The diaphragms 116, 117 are fully welded to the inner surfaces of the flanges 111, 112 and fillet welded to the web 113 of the column 110. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 4-44546 Summary of the Invention [Problem to be solved by the invention]

[0008] Conventional beam-step joint structures, including the structure shown in Fig. 4, have the problem of increased welding volume due to the increased number of locations requiring full penetration welding. Also, the need for H-shaped steel column 110 and multiple diaphragms 114, 115, 116, and 117 increases the amount of steel frame required. [Means for solving the problem]

[0009] The joint structure of a beam step that solves the above problem is applied to a column-beam joint of a reinforced concrete column and a steel beam, and is a joint structure of a beam step that is formed by connecting a first connecting beam material connected to a first beam material and a second connecting beam material provided above the first connecting beam material and connected to a second beam material in a stepped manner, The first connecting beam material is an H-shaped steel having a first lower flange, a first upper flange, and a first web connecting the first lower flange and the first upper flange, The second connecting beam material is an H-shaped steel having a second lower flange, a second upper flange, and a second web connecting the second lower flange and the second upper flange, The second connecting beam member has a flange missing portion in which a part of the second lower flange is missing, a first welded portion where a lower end portion of the second web in the flange missing portion and an upper surface of the first upper flange are welded; The flange has a second welded portion at which an end of the first upper flange and an end of the second lower flange adjacent to the flange missing portion are welded.

[0010] The joint structure of a beam step that solves the above problem is applied to a column-beam joint of a reinforced concrete column and a steel beam, and is a joint structure of a beam step that is formed by connecting a first connecting beam material connected to a first beam material and a second connecting beam material provided above the first connecting beam material and connected to a second beam material in a stepped manner, The first connecting beam material is an H-shaped steel having a first lower flange, a first upper flange located above the first lower flange, and a first web connecting the first lower flange and the first upper flange, The second connecting beam material is an H-shaped steel having a second lower flange, a second upper flange located above the second lower flange, and a second web connecting the second lower flange and the second upper flange, The first connecting beam member has a flange missing portion in which a part of the first upper flange is missing, a first welded portion where an upper end portion of the first web in the flange missing portion and a lower surface of the second lower flange are welded together; The flange has a second welded portion at which an end of the second lower flange and an end of the first upper flange adjacent to the flange missing portion are welded. [Effects of the Invention]

[0011] According to the present invention, the amount of welding and the amount of steel can be reduced. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a perspective view of a first embodiment of a joint structure for a beam step portion. [Figure 2] FIG. 2 is a cross-sectional view of the joint structure of FIG. [Figure 3] FIG. 3 is a cross-sectional view of a second embodiment of a joint structure for a beam step portion. [Figure 4] FIG. 4 is a cross-sectional view of a conventional joint structure at a beam step. DETAILED DESCRIPTION OF THE INVENTION

[0013] (First embodiment) Hereinafter, a first embodiment of a joint structure for a beam step portion will be described with reference to FIGS.

[0014] As shown in Figures 1 and 2, the joint structure of a beam step (hereinafter referred to as joint structure) is applied to a column-beam joint in which the column 90 is made of reinforced concrete (RC) and the beams 10, 20, 40, and 50 are made of steel (S).

[0015] <Column 90> 1 and 2, the column 90 is of a known reinforced concrete construction and includes a column body 91 made of concrete and a plurality of reinforcing bars 92 embedded in the column body 91. Note that in FIG. 1, the portion of the column body 91 above the joint structure described below is omitted.

[0016] The joint structure is formed by connecting a first connecting beam 10 connected to a first beam 40 and a second connecting beam 20 provided above the first connecting beam 10 and connected to a second beam 50 in a stepped manner within the column body 91.

[0017] Each component of the joint structure will be explained in detail below. <First connecting beam 10> As shown in Figures 1 and 2, the first connecting beam material 10 consists of an H-shaped steel having a first lower flange 11, a first upper flange 12 located above the first lower flange 11, and a first web 13 connecting the first lower flange 11 and the first upper flange 12.

[0018] Orthogonal beams 101, 102, each made of two H-shaped steel beams, are connected to both side surfaces of the first connecting beam 10. The orthogonal beams 101, 102 extend in a direction (orthogonal to the plane of the paper in FIG. 2) perpendicular to the extension direction of the first connecting beam 10 (left-right direction in FIG. 2). The orthogonal beams 101, 102 are connected to the first connecting beam 10 within the column main body 91 by welding.

[0019] <Second connecting beam 20> 1 and 2, the second connecting beam 20 is made of an H-shaped steel having a second lower flange 21, a second upper flange 22 located above the second lower flange 21, and a second web 23 connecting the second lower flange 21 and the second upper flange 22. The thickness of the second lower flange 21 is equal to or less than the thickness of the first upper flange 12.

[0020] The second connecting beam 20 extends in the same direction as the first connecting beam 10 (the left-right direction in FIG. 2). The second connecting beam 20 has a flange missing portion 24 where a part of the second lower flange 21 is missing. In the flange missing portion 24, the end of the second web 23 forms the lower end of the second connecting beam 20.

[0021] <First welding part 31> 2, the joint structure has a first weld 31 formed by welding the lower end 25 of the second web 23 in the flange-missing portion 24 to the upper surface of the first upper flange 12. The first weld 31 is, for example, a fillet weld. Note that the first weld 31 may also be a partial penetration weld.

[0022] <Second welded portion 32> As shown in Fig. 2, the joint structure has a second welded portion 32 where the end of the first upper flange 12 is welded to the end of the second lower flange 21 adjacent to the flange missing portion 24. The second welded portion 32 is a full penetration weld.

[0023] <First beam 40> As shown in Figures 1 and 2, the first beam 40 is made of an H-shaped steel having a lower flange 41, an upper flange 42 located above the lower flange 41, and a web 43 connecting the lower flange 41 and the upper flange 42.

[0024] The first beam 40 extends in the direction in which the first connecting beam 10 extends (the left-right direction in FIG. 2). The joint structure includes a splice plate 61 that is overlapped with the first web 13 and the web 43, and a plurality of bolts 62 that connect the splice plate 61 to the first web 13 and the web 43, respectively.

[0025] The joint structure includes a connecting plate 71 overlapped on the lower surface of the first lower flange 11 and the lower surface of the lower flange 41, and a connecting plate 72 overlapped on the upper surface of the first lower flange 11 and the upper surface of the lower flange 41. The connecting plate 71, the first lower flange 11, the lower flange 41, and the connecting plate 72 are connected by a plurality of bolts 73.

[0026] The joint structure includes a connecting plate 74 overlapped on the lower surface of the first upper flange 12 and the lower surface of the upper flange 42, and a connecting plate 75 overlapped on the upper surface of the first upper flange 12 and the upper surface of the upper flange 42. The connecting plate 74, the first upper flange 12, the upper flange 42, and the connecting plate 75 are connected by a plurality of bolts 76.

[0027] <Second beam 50> As shown in FIGS. 1 and 2, the second beam member 50 has a main beam member 51 and a sub-beam member 55.

[0028] The main beam 51 is made of an H-shaped steel having a main lower flange 52, a main upper flange 53 located above the main lower flange 52, and a main web 54 connecting the main lower flange 52 and the main upper flange 53. The main beam 51 has a beam diameter smaller than that of the second connecting beam 20.

[0029] The sub-beam 55 is made of a cut T-shaped steel having a sub-lower flange 56 and a sub-web 57 protruding upward from the upper surface of the sub-lower flange 56. The sub-beam 55 is located below the main beam 51.

[0030] <Third welding part 33> 2, the joint structure has a third weld 33 where the lower surface of the main lower flange 52 is welded to the upper end of the sub-web 57. The third weld 33 is, for example, a fillet weld. Note that the third weld 33 may also be a partial penetration weld.

[0031] <Main connecting member 63> As shown in FIGS. 1 and 2, the joint structure includes a main connecting member 63 that connects the second connecting beam 20 and the main beam 51.

[0032] The main connecting member 63 has a splice plate 64 that is overlaid on the second web 23 and the main web 54, and a plurality of bolts 65 that connect the splice plate 64 to the second web 23 and the main web 54, respectively.

[0033] <Sub-connecting member 66> As shown in FIGS. 1 and 2, the joint structure includes a sub-connecting member 66 that connects the second connecting beam 20 and the sub-beam 55.

[0034] The sub-connecting member 66 has a splice plate 67 that is overlapped with the second web 23 and the sub-web 57, and a plurality of bolts 68 that connect the splice plate 67 to the second web 23 and the sub-web 57, respectively.

[0035] The joint structure includes a connecting plate 81 overlapped on the lower surface of the second lower flange 21 and the lower surface of the sub-lower flange 56, and a connecting plate 82 overlapped on the upper surface of the second lower flange 21 and the upper surface of the sub-lower flange 56. The connecting plate 81, the second lower flange 21, the sub-lower flange 56, and the connecting plate 82 are connected by a plurality of bolts 83.

[0036] The joint structure includes a connecting plate 84 overlapped on the lower surface of the second upper flange 22 and the lower surface of the main upper flange 53, and a connecting plate 85 overlapped on the upper surface of the second upper flange 22 and the upper surface of the main upper flange 53. The connecting plate 84, the second upper flange 22, the main upper flange 53, and the connecting plate 85 are connected by a plurality of bolts 86.

[0037] Next, the effects of the first embodiment will be described. (1) The joint structure of the beam step is applied to the column-beam joint of a reinforced concrete column-steel beam construction, and is composed of a first connecting beam 10 connected to a first beam 40 and a second connecting beam 20 provided above the first connecting beam 10 and connected to a second beam 50, connected in a stepped manner.

[0038] The first connecting beam 10 and the second connecting beam 20 are made of H-shaped steel. The second connecting beam 20 has a flange missing portion 24 where a part of the second lower flange 21 is missing. The joint structure has a first welded portion 31 where the lower end portion 25 of the second web 23 in the flange missing portion 24 is welded to the upper surface of the first upper flange 12. The joint structure has a second welded portion 32 where the end of the first upper flange 12 is welded to the end of the second lower flange 21 adjacent to the flange missing portion 24.

[0039] This structure simplifies the joint structure by eliminating the need for H-shaped steel beam posts and diaphragms, which were previously required for joints at beam steps in conventional RC column-S beam structures. This reduces the amount of welding and steel frame required.

[0040] (2) The second beam 50 has a main beam 51 made of H-shaped steel and a sub-beam 55 made of cut T-shaped steel and located below the main beam 51. The joint structure has a main connecting member 63 that connects the second connecting beam 20 and the main beam 51, and a sub-connecting member 66 that connects the second connecting beam 20 and the sub-beam 55.

[0041] According to this configuration, by providing the sub-beam 55, it is possible to eliminate the difference in beam diameter between the main beam 51 of the second beam 50 and the second connecting beam 20. As a result, even if the beam diameter of the main beam 51 of the second beam 50 is smaller than the beam diameter of the second connecting beam 20, the second connecting beam 20 and the main beam 51 of the second beam 50 can be firmly connected.

[0042] (3) The main connecting member 63 includes a splice plate 64 that is overlaid on the second web 23 and the main web 54, and a plurality of bolts 65 that connect the splice plate 64 to the second web 23 and the main web 54, respectively.

[0043] With this configuration, the second connecting beam 20 and the main beam 51 of the second beam 50 can be easily and firmly connected.

[0044] (Second embodiment) Next, a second embodiment of the joint structure for a beam step portion will be described with reference to Fig. 3. In the second embodiment, the same or corresponding components as those in the first embodiment will be denoted by the same reference numerals, and redundant description will be omitted.

[0045] The second embodiment differs from the first embodiment in that the plate thickness of the second lower flange 21 is equal to or greater than the plate thickness of the first upper flange 12, and that a flange missing portion 26 is provided in the first connecting beam 10 instead of the second connecting beam 20. The following description will focus on the differences from the first embodiment.

[0046] As shown in Figure 3, the first connecting beam 10 has a flange missing portion 26 where a portion of the first upper flange 12 is missing. The joint structure has a first welded portion 31 where the upper end portion 27 of the first web 13 in the flange missing portion 26 is welded to the underside of the second lower flange 21. The joint structure has a second welded portion 32 where the end portion of the second lower flange 21 is welded to the end portion of the first upper flange 12 adjacent to the flange missing portion 26.

[0047] Although the first connecting beam 10 shown in Figure 3 does not have orthogonal beams 101 and 102 connected to it, the orthogonal beams 101 and 102 may be connected to the first connecting beam 10, as in the above embodiment.

[0048] This configuration can achieve the same effects as the effects (1) to (3) of the above embodiment. While the components of the joint structure of the present invention have been described above based on the first and second embodiments, the joint structure of the present invention only needs to include at least the first connecting beam 10, the first beam 40, the second connecting beam 20, and the second beam 50 (main beam 51) as beams. Therefore, the joint structure of the present invention may not necessarily include the sub-beam 55 shown in Figures 1 to 3.

[0049] <Example of change> This embodiment can be modified as follows: This embodiment and the following modifications can be combined and implemented within the scope of technical compatibility.

[0050] The orthogonal beams 101 and 102 can also be omitted.

[0051] The connecting plates 71, 72 and the bolts 73 that connect the lower flange 41 and the first lower flange 11 may be omitted. Also, instead of the connecting plates 71, 72 and the bolts 73, the lower flange 41 and the first lower flange 11 may be connected by welding.

[0052] The connecting plates 74, 75 and the bolts 76 that connect the upper flange 42 and the first upper flange 12 may be omitted. Also, instead of the connecting plates 74, 75 and the bolts 76, the upper flange 42 and the first upper flange 12 may be connected by welding.

[0053] The connecting plates 81, 82 and bolts 83 that connect the second lower flange 21 and the sub-lower flange 56 may be omitted. Also, instead of the connecting plates 81, 82 and bolts 83, the second lower flange 21 and the sub-lower flange 56 may be connected by welding.

[0054] The connecting plates 84, 85 and the bolts 86 that connect the second upper flange 22 and the main upper flange 53 may be omitted. Also, instead of the connecting plates 84, 85 and the bolts 86, the second upper flange 22 and the main upper flange 53 may be connected by welding. [Explanation of symbols]

[0055] 10...first connecting beam, 11...first bottom flange, 12...first top flange, 13...first web, 20...second connecting beam, 21...second bottom flange, 22...second top flange, 23...second web, 24...flange missing portion, 25...bottom end, 26...flange missing portion, 27...top end, 31...first weld, 32...second weld, 33...third weld, 40,140...first beam, 41,141...bottom flange, 42,142...top flange, 43...web, 50...second beam, 51...main beam, 52...main bottom flange, 53...main top flange, 54...main web, 55...sub beam, 56...sub bottom flange, 57...sub web, 61...splice plate, 62 ...Bolt, 63...Main connecting member, 64...Splice plate, 65...Bolt, 66...Sub-connecting member, 67...Splice plate, 68...Bolt, 71...Connecting plate, 72...Connecting plate, 73...Bolt, 74...Connecting plate, 75...Connecting plate, 76...Bolt, 81...Connecting plate, 82...Connecting plate, 83...Bolt, 84...Connecting plate, 85...Connecting plate, 86...Bolt, 90...Column, 91...Column body, 92...Reinforcing bar, 101, 102...Orthogonal beam, 110...Stud column, 111, 112...Flange, 113...Web, 114, 115, 116, 117...Diaphragm, 150...Second beam, 151...Lower flange, 152...Upper flange

Claims

1. This joint structure is applied to a column-beam joint of a reinforced concrete column and a steel beam, and is formed by connecting a first connecting beam member connected to a first beam member and a second connecting beam member provided above the first connecting beam member and connected to a second beam member in a stepped manner, the first connecting beam material is an H-shaped steel having a first lower flange, a first upper flange located above the first lower flange, and a first web connecting the first lower flange and the first upper flange; the second connecting beam member is an H-shaped steel having a second lower flange, a second upper flange located above the second lower flange, and a second web connecting the second lower flange and the second upper flange; The second connecting beam member has a flange missing portion in which a part of the second lower flange is missing, a first welded portion at which a lower end portion of the second web in the flange missing portion and an upper surface of the first upper flange are welded; a second welded portion at which an end of the first upper flange and an end of the second lower flange adjacent to the flange missing portion are welded together; Joint structure at the beam step.

2. This joint structure is applied to a column-beam joint of a reinforced concrete column and a steel beam, and is formed by connecting a first connecting beam member connected to a first beam member and a second connecting beam member provided above the first connecting beam member and connected to a second beam member in a stepped manner, the first connecting beam material is an H-shaped steel having a first lower flange, a first upper flange located above the first lower flange, and a first web connecting the first lower flange and the first upper flange; the second connecting beam member is an H-shaped steel having a second lower flange, a second upper flange located above the second lower flange, and a second web connecting the second lower flange and the second upper flange; The first connecting beam member has a flange missing portion in which a part of the first upper flange is missing, a first welded portion formed by welding an upper end portion of the first web in the flange missing portion to a lower surface of the second lower flange; a second welded portion at which an end of the second lower flange and an end of the first upper flange adjacent to the flange missing portion are welded together; Joint structure at the beam step.

3. The second beam material is a main beam member made of an H-shaped steel having a main lower flange, a main upper flange located above the main lower flange, and a main web connecting the main lower flange and the main upper flange, the main beam member having a beam diameter smaller than that of the second connecting beam member; a sub-beam member positioned below the main beam member, the sub-beam member being made of a cut-tee steel having a sub-lower flange and a sub-web protruding upward from an upper surface of the sub-lower flange; a main connecting member that connects the second connecting beam member and the main beam member; a sub-connecting member that connects the second connecting beam member and the sub-beam member; a third welded portion at which the main lower flange and the upper end portion of the sub-web are welded, A joint structure for a beam step portion according to claim 1 or claim 2.

4. The main connecting member includes a splice plate overlapping the second web and the main web, and a plurality of bolts connecting the splice plate to the second web and the main web, respectively. The joint structure of a beam step portion according to claim 3.

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