Steel joint structure

Abstract

To prevent degradation of flexural rigidity of joint pieces in joining two steel materials combined in a state of axially intersecting by using a bolt, while preventing projection of a bolt head portion from a surface of the joint piece of the other steel material.SOLUTION: A gusset plate 3 is welded to a surface of one of steel materials 1 in a manner of protruding to a side of the other steel material 2, a doubling plate 4 is welded to a surface at one side in a plate thickness direction of a joint piece 21 of the other steel material 2, an insertion hole 21a of a size enough to insert a part of a head portion 51 of the bolt 5 is formed on the joint piece 21 of the other steel material 2 at a position to insert the bolt 5, further a seat digging 4b of a depth enough to insert a part of the head portion 51 of the bolt 5 is formed at a head portion 51 side of the bolt 5 of the doubling plate 4, the doubling plate 4 is superposed on the gusset plate 3, and the bolt 5 is inserted to the insertion hole 21a of the other steel material 2 and insertion holes 4a, 3a of the doubling plate 4 and the gusset plate 3 to join the other steel material 2 to one of the steel material 1.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a joint structure of steel materials in which two steel materials are joined together with their axial directions crossing each other using a bolt. [Background technology]

[0002] When joining two steel materials whose axial directions intersect with each other using a bolt, if a joining piece such as the web or flange of one steel material is placed on a joining piece such as the other steel material and the bolt is passed through both joining pieces, it may be necessary to reduce the amount by which the bolt head protrudes from the surface of the joining piece for reasons such as fitting of finishing materials. In such cases, there is a method of forming a counterbore that is continuous with the insertion hole of the steel material and into which the bolt head fits (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2003-247590 A (Claim 2, paragraphs 0014, 0020-0032, Figures 2-5) Summary of the Invention [Problem to be solved by the invention]

[0004] However, in cases where the thickness of the plate to be joined, such as the steel joining piece, including the steel plate in Patent Document 1, is equal to or less than the height of the bolt head, it is not possible to form a countersink in the plate (joining piece) itself.

[0005] If the plate is thicker than the height of the bolt head, it is possible to form a countersink in the plate as shown in Figure 3. However, because the countersink is continuous with the insertion hole, has an inner diameter larger than the inner diameter of the insertion hole, and is formed from the surface of the plate, the bending rigidity of the insertion hole portion of the plate will be extremely reduced, and there is a possibility that the stress transmission performance required for the joint will not be ensured.

[0006] In view of the above background, the present invention proposes a joint structure that, when joining steel joint pieces with a bolt, prevents the bolt head from protruding while avoiding a decrease in the bending rigidity of the joint pieces. [Means for solving the problem]

[0007] The joint structure of steel materials described in claim 1 is a joint structure of steel materials in which two steel materials that are combined in a state where their axial directions intersect each other are joined using bolts, A gusset plate that protrudes toward the other steel material is welded to the surface of one of the two steel materials, and a splice plate that faces the gusset plate is welded to one surface in the plate thickness direction of the joining piece of the other steel material, An insertion hole having a size that allows at least a part of the head of the bolt to be inserted is formed in the joining piece of the other steel material at a position where the bolt is inserted, and a counterbore having a depth that allows a part of the head of the bolt to be inserted is formed on the head side of the bolt of the splice plate, The shape and dimensions of the insertion hole of the joining piece of the other steel material and the countersink of the splice plate are the same, The constituent elements are that the other steel material directly or indirectly overlaps the gusset plate in the support plate, and the shank of the bolt is joined to the one steel material by passing through the insertion hole of the other steel material and the insertion holes of the support plate and the gusset plate.

[0008] As shown in Figures 1 and 2, two steel materials 1, 2 are joined together by directly or indirectly overlapping a gusset plate 3 as a joining piece welded to the surface of one steel material 1 with a splice plate 4 welded to the other steel material 2, and a nut 6 is screwed onto the shank 52 of a bolt 5 that passes through the splice plate 4 and gusset plate 3. The splice plate 4 is welded to the gusset plate 3 side of a joining piece 21 such as a web or flange of the other steel material 2, and is integrated with it. The shank 52 of the bolt 5 passes through the insertion hole 4a of the splice plate 4 and the insertion hole 3a of the gusset plate 3.

[0009] "A gusset plate that protrudes toward the other steel material is welded to the surface of one steel material" means that the gusset plate 3 is welded to the surface of one steel material 1 so as to protrude toward the joint (joint piece 21) side with the other steel material 2. "The joint side with the other steel material 2" refers to the joint piece 21 side of the other steel material 2. "A splice plate is welded to one surface in the plate thickness direction of the joint piece of the other steel material" means that the splice plate 4 is welded overlapping the gusset plate 3 side of the joint piece 21 of the other steel material 2.

[0010] The phrase "a through hole into which at least part of the head of the bolt can be inserted is formed in the joining piece of the other steel material" means that in the axial direction of the bolt 5, a part of the shank 52 side of the head 51 may fit into the through hole 21a of the joining piece 21, or the entire head 51 may fit into the through hole 21a. This depends on the plate thickness of the joining piece 21 and the depth of the countersink 4b of the splice plate 4, as will be described later. Since it is sufficient for at least part of the head 51 to be inserted into the through hole 21a of the joining piece 21 in the axial direction, part of the head 51 may be exposed from the surface of the steel material 2.

[0011] The phrase "an insertion hole large enough to allow at least a portion of the head of the bolt to be inserted" means that the insertion hole 21a of the joint piece 21 is large enough to allow at least a portion of the shank 52 side of the head 51 of the bolt 5 to be inserted (sat within the insertion hole 21a). The size here refers to the area of ​​the inner periphery of the insertion hole 21a when viewed in the axial direction of the bolt 5.

[0012] "A countersink is formed on the bolt head side of the splice plate" means that a countersink 4b is formed that continues (communicates) with the insertion hole 4a from the surface of the splice plate 4 on the joining piece 21 side that overlaps the gusset plate 3 side of the joining piece 21. Since the head 51 of the bolt 5 is inserted into the countersink 4b through the insertion hole 21a of the joining piece 21, the insertion hole 21a of the joining piece 21 continues with the countersink 4b of the splice plate 4 and appears to be part of the countersink 4b.

[0013] The insertion hole 21a of the joint piece 21 becomes part of the countersink 4b of the splice plate 4, so that at least a portion of the head 51 of the bolt 5 is fitted in the depth direction (axial direction) within the countersink 4b and the insertion hole 21a of the joint piece 21. In this relationship, the insertion hole 21a of the joint piece 21 has a size that allows at least a portion of the head 51 of the bolt 5 to be inserted therein.

[0014] Furthermore, if the sum of the plate thickness of the joining piece 21 of the other steel material 2 and the depth of the countersink 4b of the splice plate 4 is equal to or greater than the height of the head 51 of the bolt 5 (claim 2), it is possible to prevent the entire head 51 of the bolt 5 from protruding from the insertion hole 21a of the joining piece 21. In this case, since the end face of the head 51 of the bolt 5 does not protrude from the surface of the joining piece 21, it becomes possible to install or adhere a finishing material uniformly along the surface of the joining piece 21 without creating unevenness in the finished surface.

[0015] Countersink 4b of splice plate 4 is formed to accommodate part of head 51 of bolt 5, so part of head 51 passes through insertion hole 21a of joint piece 21 and fits within countersink 4b, with the bottom surface of head 51 in close contact with the bottom of countersink 4b or a washer placed at the bottom. Countersink 4b has a depth that allows part of shank 52 of head 51 to be inserted (fit). "Part of head 51 can be inserted" means that, since bolt head 51 also fits within insertion hole 21a of splice plate 21, only part of head 51 of bolt 5 fits within countersink 4b.

[0016] The head 51 of the bolt 5 passes through the insertion hole 21a of the joint piece 21 and enters the countersink 4b of the support plate 4, and is in direct or indirect contact with the bottom of the countersink 4b. Therefore, if the insertion hole 21a and the countersink 4b are both circular or have the same shape, the inside dimension (inner diameter) of the insertion hole 21a is formed to be larger than or equal to the inside dimension (inner diameter) of the countersink 4b.

[0017] In particular, as shown in Figs. 1-(b) and 1-(c), the shape and dimensions of the insertion hole 21a of the joint piece 21 and the countersink 4b of the splice plate 4 are made the same. By doing (Claim 1), making it easier to insert the head 51 of the bolt 5 into the insertion hole 21a and the countersink 4b. The "shape of the insertion hole 21a and the countersink 4b" refers to the shape of the inner peripheral surfaces of the insertion hole 21a and the countersink 4b when viewed in the axial direction of the bolt 5, and can be circular, hexagonal, or the like. The "dimensions" refers to the fact that the inside dimensions, such as the inner diameter, of the insertion hole 21a and the inside dimensions, such as the inner diameter, of the countersink 4b are equal. If the shapes of the insertion hole 21a and the countersink 4b are both circular, the inside diameters of both are equal.

[0018] Here, by making the inside dimension (inner diameter) of the insertion hole 21a and the inside dimension (inner diameter) of the countersink 4b equal to the outside dimension (face width or diagonal distance) or outer diameter of the head 51 of the bolt 5, the head 51 of the bolt 5 can be inserted into the insertion hole 4a of the support plate 4 using the inner surfaces of the insertion hole 21a and the inner surfaces of the countersink 4b as guide surfaces, thereby improving the efficiency of the bolt 5 insertion work.

[0019] In this case, strictly speaking, it is also assumed that the centers of the insertion hole 3a of the gusset plate 3 and the insertion hole 4a of the splice plate 4, and the center of the countersink 4b and the center of the insertion hole 21a of the joint piece 21, coincide with each other. "Center" refers to the center when viewed in the axial direction of the bolt 5. It is also assumed that the center of the shank 52 and the center of the head 51 of the bolt 5 coincide with each other, and that this center also coincides with the centers of the insertion holes 3a, 4a, etc.

[0020] As described above, by forming the countersink 4b in the splice plate 4 that is welded to the joint piece 21 of the other steel material 2, it becomes possible to accommodate the head 51 of the bolt 5 that passes through the other steel material 2, even when the plate thickness of the joint piece 21 of the other steel material 2 is equal to or less than the height of the bolt head 51. By fitting the head 51 of the bolt 5 within the countersink 4b of the splice plate 4 and the insertion hole 21a of the joint piece 21, protrusion of the bolt head 51 from the surface of the joint piece 21 is reduced, and it is also possible to prevent it from protruding.

[0021] Furthermore, the splice plate 4 overlaps the area including the insertion hole 21a of the other steel material 2 and is integrated with the other steel material 2, thereby increasing the plate thickness of the other steel material 2 and stiffening the area including the insertion hole 21a formed in the joining piece 21 of the other steel material 2, thereby compensating for the decrease in strength and rigidity caused by forming the insertion hole 21a in the joining piece 21. Compensating for the strength and rigidity of the joining piece 21 of the other steel material 2 makes it easier to ensure the stress transmission performance of the joining piece 21 of the other steel material 2. [Effects of the Invention]

[0022] A support plate that faces the gusset plate welded to the surface of one of the steel materials is welded to the joining piece of the other steel material, a through hole is formed in the joining piece into which at least part of the bolt head can be inserted, and a countersink is formed on the bolt head side of the support plate into which part of the bolt head can be inserted.Therefore, even if the plate thickness of the joining piece of the other steel material is equal to or less than the height of the bolt head, the bolt head can be contained within the countersink in the support plate and within the through hole in the other steel material, and protrusion of the bolt head from the surface of the joining piece can be prevented.

[0023] The support plate reinforces and stiffens the area including the insertion hole formed in the joining piece of the other steel material, so that even while forming an insertion hole in the joining piece, it can compensate for the decrease in strength and rigidity of the joining piece and ensure the stress transmission performance of the joining piece. [Brief explanation of the drawings]

[0024] [Figure 1] (a) is an elevation view showing how, when one steel material is a square steel and the other is a channel steel, a gusset plate welded to the surface of one steel material is placed on top of a splice plate welded to the back of the web, which is the connecting piece of the other steel material, and the two steel materials are joined using bolts that are parallel in the height direction of the connecting pieces; (b) is a cross-sectional view taken along line xx in (a), and (c) is a cross-sectional view taken along line yy in (a). [Figure 2] (a) is an elevational view showing the same steel material combination as in Figure 1, where two steel materials are joined using bolts parallel to the axial direction of the joining pieces, (b) is a cross-sectional view taken along line xx in (a), and (c) is a cross-sectional view taken along line yy in (a). [Figure 3] FIG. 10 is an elevation view showing a conventional joining example in which a countersink is formed in the thickness direction from the surface side of the steel material, continuing into an insertion hole formed in the other steel material; (b) is a cross-sectional view taken along line xx in (a); and (c) is a cross-sectional view taken along line yy in (a). DETAILED DESCRIPTION OF THE INVENTION

[0025] Figure 1 shows an example of a joint in which two steel materials 1, 2 are joined together, and a gusset plate 3 is welded to the surface of one steel material 1, protruding toward the other steel material 2, and a splice plate 4 facing the gusset plate 3 is welded to one surface in the thickness direction of a joining piece 21 of the other steel material 2, and the two are joined with a bolt 5 that passes through the splice plate 4 and the gusset plate 3. The set plate 3 is welded to the surface of one steel material 1, protruding toward the joining piece 21 of the other steel material 2. The splice plate 4 is welded to the gusset plate 3 side of the joining piece 21 of the other steel material 2, such as a web.

[0026] The other steel material 2 is placed directly or indirectly on the gusset plate 3 at the splice plate 4. As shown in Figures 1-(b) and 1-(c), the shank 52 of the bolt 5 passes through the insertion hole 21a of the connecting piece 21, the insertion hole 4a of the splice plate 4, and the insertion hole 3a of the gusset plate 3, and protrudes from the surface of the gusset plate 3 opposite the splice plate 4. A nut 6 is screwed onto the shank 52 protruding from the back surface of the gusset plate 3, and the bolt 5 joins the other steel material 2 to the one steel material 1.

[0027] At the position of the joining piece 21 of the other steel material 2 where the bolt 5 is inserted, an insertion hole 21a is formed with a size (area) that allows at least a part of the axial direction of the head 51 of the bolt 5 to be inserted, and on the head 51 side of the bolt 5 of the splice plate 4, a countersink 4b is formed with a depth that allows a part of the head 51 of the bolt 5 to be inserted. The (inner surface of) the countersink 4b has a shape that follows the shape of the head 51 of the bolt 5 and is formed in a circular or polygonal shape, but when the shape of the head 51 is hexagonal, the countersink 4b may also be formed in a circular shape.

[0028] 1-(b) and 1-(c), the splice plate 4 is joined directly to the gusset plate 3 side of the connecting piece 21, and because the space within the countersink 4b is continuous with the space within the insertion hole 21a of the splice plate 21, the depth of the insertion hole 21a (the plate thickness of the splice plate 21) serves to increase the depth of the countersink 4b. The insertion hole 21a of the connecting piece 21 is large enough to allow at least a portion of the head 51 to be inserted, so that the insertion hole 21a has the capacity to accommodate the head 51 together with the countersink 4b as part of the space within the countersink 4b.

[0029] 1 and 2 show an example in which one steel material 1 is a square steel and the other steel material 2 is a channel steel, and they are joined with bolts 5 that penetrate gusset plates 3 and splice plates 4 that are integrated with each other, but the type of steel material 1 is not important as long as the gusset plates 3 for bolt joining are protruding from the surface. The type of steel material 2 is also not important as long as it is joined with bolts at plate elements such as joining pieces 21.

[0030] Figure 1 shows the case where two steel materials 1 and 2 are joined using bolts 5, 5 that are parallel in the height direction (width direction) of the other steel material 2, and Figure 2 shows the case where two steel materials 1 and 2 are joined using bolts 5, 5 that are parallel in the axial direction of the other steel material 2. If the other steel material 2 is a channel steel and the joining piece 21 is a web, the splice plate 4 overlaps the part of the web (joining piece 21) excluding the fillet, and is welded at the part near the flange.

[0031] The head 51 of the bolt 5 is inserted from the insertion hole 21a of the joint piece 21 toward the back plate 4 and enters the countersink 4b of the back plate 4, so that if the insertion hole 21a and the countersink 4b are both circular, for example, the inner diameter (inside dimension) of the insertion hole 21a will be equal to or larger than the inner diameter (inside dimension) of the countersink 4b. The head 51 comes into direct or indirect contact with the bottom of the countersink 4b.

[0032] In other words, when the splice plate 4 is joined to the joining piece 21, the inner peripheral surface of the insertion hole 21a and the inner peripheral surface of the countersink 4b are substantially continuous, or the inner peripheral surface of the insertion hole 21a is located more radially outward with respect to the center of the bolt 5 as viewed in the axial direction than the inner peripheral surface of the countersink 4b. Figures 1 and 2 show examples where the shapes and dimensions of the insertion hole 21a and the countersink 4b are equal when viewed in the axial direction of the bolt 5. The dimensions are inside dimensions (inner diameters). In these examples, the shapes of the insertion hole 21a and the countersink 4b are circular as shown in (a), but they may also be hexagonal or other shapes.

[0033] In this case, if the inside dimensions (inner diameters) of the insertion hole 21a and the countersink 4b are made equal to the outside dimensions (face width or diagonal distance) of the head 51 of the bolt 5, or the outside diameter of the head 51 as shown in (b) and (c) of each figure, the inner surfaces of the insertion hole 21a and the countersink 4b can be used as guide surfaces to guide the head 51 of the bolt 5, allowing the shank 52 of the bolt 5 to be smoothly inserted into the insertion hole 4a of the support plate 4.

[0034] 1 and 2 also show an example in which the sum of the plate thickness of the joining piece 21 of the other steel material 2 and the depth of the countersink 4b of the splice plate 4 is equal to or greater than the height of the head 51 of the bolt 5. In this case, the axial end face of the head 51 of the bolt 5 can be prevented from protruding from the surface of the joining piece 21, making it possible to uniformly prepare the surface of the finishing material that is to be attached to the surface of the joining piece 21.

[0035] As described above, the thickness of the joint piece 21 serves to increase the depth of the countersink 4b, so in order to prevent the head 51 of the bolt 5 from protruding from the surface of the joint piece 21, the depth of the countersink 4b itself of the support plate 4 should be at least the height of the head 51 minus the thickness of the joint piece 21. [Explanation of symbols]

[0036] 1...One steel material, 2...other steel material, 21...joint piece, 21a...through hole, 3... gusset plate, 3a... insertion hole, 4...splicing plate, 4a...insertion hole, 4b...counter groove, 5...Bolt, 51...Head, 52...Shaft, 6...Nat.

Claims

1. This is a steel joint structure in which two steel members, whose axial directions intersect with each other, are joined using bolts. A gusset plate that protrudes toward the other steel material is welded to a surface of one of the two steel materials, and a splice plate that faces the gusset plate is welded to a surface on one side in the plate thickness direction of the joining piece of the other steel material, An insertion hole having a size that allows at least a part of the head of the bolt to be inserted is formed in the joining piece of the other steel material at a position where the bolt is inserted, and a counterbore having a depth that allows a part of the head of the bolt to be inserted is formed on the head side of the bolt of the splice plate, The shape and dimensions of the insertion hole of the joining piece of the other steel material and the countersink of the splice plate are the same, A steel joint structure characterized in that the other steel material directly or indirectly overlaps the gusset plate in the support plate, and the bolt is joined to the one steel material by inserting it through the insertion hole of the other steel material and the insertion holes of the support plate and the gusset plate.

2. 2. The steel joint structure according to claim 1, wherein the sum of the plate thickness of the joining piece of the other steel material and the depth of the countersink of the support plate is equal to or greater than the height of the head of the bolt.

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