JP5638905B2 - Steel pipe column joint reinforcement structure - Google Patents

Description

  The present invention relates to a joint portion reinforcing structure for a steel pipe column.

  2. Description of the Related Art Conventionally, a through diaphragm type and a thickened panel type are known as a column / beam joint structure for joining steel beams having an H-shaped cross section to circular or square steel pipe columns.

  Through-diaphragm formation is, for example, a structure in which a steel pipe column is cut at the joining position of the flange portion and the web portion of the beam, a ring-shaped diaphragm is sandwiched between them and welded to the steel tube column, and the flange portion of the beam is welded to the diaphragm. is there. However, through-diaphragm formation requires cutting of the steel pipe column and welding process with the diaphragm, and there are diaphragm protrusions inside the steel pipe column, which makes construction difficult with respect to the insertion of rebar rods and filling of concrete. is there.

  In addition, the thickened panel type is, for example, by cutting a steel pipe column at the joining position of the flange part and web part of the beam, welding a thicker pipe thicker than the steel pipe column, and attaching the flange part of the beam to the thickened pipe. It is a welded structure. However, the thickened panel type requires cutting of the steel pipe column and welding process with the thickened pipe, and the number of steel frames of the steel pipe column may increase.

  On the other hand, as a form in which the column is not cut at the joining position of the flange portion and the web portion of the beam, the following Patent Document 1 discloses that when the octagonal steel column and the steel beam are joined via the joining hardware, A structure is disclosed in which a pair of bolt joints provided on both sides in the width direction is formed in an eight-shape, and a bolt joint of a joint metal and a steel column are joined by one side bolt.

  Further, in Patent Document 2 below, an external steel pipe is arranged on the outer periphery of a steel pipe column, a beam joining piece part and a joining member having a slit joining part are inserted into a slit formed in the external steel pipe, and the beam joining piece part is externally attached. The steel pipe column, external steel pipe and joint member are integrated by projecting to the outside of the steel pipe, joining the beam joint piece and the beam flange, and filling the gap between the external steel pipe and the steel pipe column with a time-hardening material. The resulting structure is disclosed.

  Further, Patent Document 3 below has a structure in which a diaphragm is provided on the outside of a steel pipe column to be joined to the beam, and a reinforcing fiber sheet-like material is attached to the steel pipe column, the beam, and the diaphragm. Is disclosed.

JP-A-8-93053 JP 2004-353441 A JP 2007-254953 A

  In the above-mentioned Patent Document 1, the steel column and the steel beam can be easily joined by one-side bolt joining the bolt joint portion of the joint metal and the steel column, but the steel column to be joined with the steel beam There is a possibility that the shear strength of the joint (joint part with the beam) will be insufficient.

  In Patent Document 2, the steel pipe column and the beam are simply joined by joining the beam joining piece of the joining member and the flange of the beam, and filling the gap between the external steel pipe and the steel pipe column with a time-hardening material. However, it is not possible to shear-reinforce the joint part (joint part with the beam) of the steel pipe column joined with the beam.

  In the above-mentioned Patent Document 3, it is possible to reinforce the weld defect portion of the steel pipe column, beam, and diaphragm by pasting the reinforcing fiber sheet material across the three types of steel pipe column, beam, and diaphragm. There is a possibility that stress is concentrated at a portion where the reinforcing fiber sheet of the steel pipe column is not attached.

  In view of the above facts, the present invention aims to reinforce the joint portion (joint portion with the beam) of the steel pipe column to be joined with the beam from the outside, thereby increasing the shear strength.

In order to achieve the above object, the steel pipe column joint reinforcing structure according to the invention of claim 1 is provided on the steel pipe column filled with concrete inside and above and below the steel pipe column joint, directly joined respectively to the outer periphery of the tubular columns, and an annular diaphragm beam flanges are joined directly provided along the outer periphery of the steel column at the joint portion, upper and lower ends are joined to the diaphragm A reinforcing member; and a plate provided on the reinforcing member and joined to the web of the beam.

According to the first aspect of the present invention, the annular diaphragm is provided above and below the joint portion of the steel pipe column filled with concrete, and the diaphragm is directly joined to the outer periphery of the steel pipe column. A reinforcing member is provided along the outer periphery of the steel pipe column at the joint, and the upper end and the lower end of the reinforcing member are joined to the upper and lower diaphragms. The flange of the beam is directly joined to the upper and lower diaphragms, and the web of the beam is joined to a plate provided on the reinforcing member. In such a configuration, the joint portion (joint portion with the beam) of the steel pipe column to be joined to the beam is reinforced by the reinforcing member provided along the outer periphery of the steel pipe column. That is, by reinforcing the joint portion of the steel pipe column from the outside by the reinforcing member, the shear strength of the joint portion can be increased.

  The steel pipe column joint reinforcement structure according to the invention of claim 2 is the tubular structure according to claim 1, wherein the reinforcing member is extrapolated by providing the steel tube column and a clearance outside the steel tube column. This is an outer steel pipe.

  According to the second aspect of the present invention, a tubular outer steel pipe as a reinforcing member is extrapolated by providing a steel pipe pillar and a clearance outside the steel pipe pillar. The tubular outer steel pipe can reinforce the joint part (joint part with the beam) of the steel pipe column joined to the beam from the outside, and can increase the shear strength of the joint part.

  In the invention, the reinforcing member is a fiber-reinforced plastic sheet that is fixed to the outer peripheral surface of the steel pipe column. .

  According to invention of Claim 3, the fiber reinforced plastic sheet as a reinforcement member is adhering to the outer peripheral surface of a steel pipe column. The fiber reinforced plastic sheet can reinforce the joint part (joint part with the beam) of the steel pipe column joined to the beam from the outside, and can increase the shear strength of the joint part.

  In the invention of claim 3, the steel tube pillar joint reinforcement structure according to the invention of claim 4 is the fiber reinforced plastic sheet, in which the reinforcing fiber sheet is affixed to the outer peripheral surface of the steel tube pillar in multiple layers, The reinforcing fiber sheet is impregnated with a resin and cured.

  According to the invention described in claim 4, the reinforcing fiber sheet is stuck in a multilayer on the outer peripheral surface of the steel pipe column, and the reinforcing fiber sheet is impregnated with the resin and cured, whereby the fiber reinforced on the outer peripheral surface of the steel pipe column. The plastic sheet can be easily fixed. Further, the shear strength of the joint can be easily adjusted by the thickness and number of reinforcing fiber sheets.

  The steel pipe column joint reinforcing structure according to the invention of claim 5 is the invention according to any one of claims 1 to 4, wherein the steel tube column includes an axial streak and a shear reinforcement. The muscles are arranged.

  According to the fifth aspect of the present invention, the axial bars and the shear reinforcement bars are arranged inside the steel pipe column, so that the thickness of the steel pipe constituting the steel pipe column can be made thinner.

  ADVANTAGE OF THE INVENTION According to this invention, the joint part (joint part with a beam) of the steel pipe column joined with a beam can be reinforced from the outside, and a shear strength can be raised.

It is a partially exploded perspective view which shows the basic composition of the joint part reinforcement structure of the steel pipe pillar which concerns on 1st Embodiment of this invention. It is a longitudinal cross-sectional view which shows the joint part reinforcement structure of the steel pipe pillar which concerns on 1st Embodiment of this invention. It is a cross-sectional view which shows the joint part reinforcement structure of the steel pipe pillar which concerns on 1st Embodiment of this invention. It is a cross-sectional view which shows the steel pipe column used for the joint part reinforcement structure of the steel pipe column which concerns on 1st Embodiment of this invention. It is a longitudinal cross-sectional view which shows the joint part reinforcement structure of the steel pipe pillar which concerns on 2nd Embodiment of this invention. It is a cross-sectional view which shows the joint part reinforcement structure of the steel pipe pillar which concerns on 2nd Embodiment of this invention. It is a perspective view which shows the construction middle of the joint part reinforcement structure of the steel pipe pillar which concerns on 2nd Embodiment of this invention.

[First Embodiment]
Hereinafter, 1st Embodiment of the joint part reinforcement structure of the steel pipe pillar of this invention is described using FIGS. 1-4.

  FIG. 1 is a partially exploded perspective view showing a basic configuration of a steel pipe column joint portion reinforcing structure 10. FIG. 2 is a longitudinal sectional view of a steel tube pillar joint portion reinforcing structure 10. Further, FIG. 3 shows a steel pipe column joint portion reinforcing structure 10 in a cross-sectional view, and FIG. 4 shows a steel pipe column 12 used in the steel pipe column joint portion reinforcing structure 10 in a cross section. It is shown in the figure.

  As shown in these drawings, the steel pipe column joint portion reinforcing structure 10 includes a columnar steel pipe column 12 erected along the vertical direction, and a joint portion 14 of the steel pipe column 12 (with the beam 22). Outer ring diaphragm type diaphragms 16 provided above and below the joining portion), cylindrical outer steel pipe 18 as a reinforcing member extrapolated outside the steel pipe column 12 between the upper and lower diaphragms 16, and upper and lower diaphragms 16 and a plate 20 joined to the outer steel pipe 18 by welding.

  A beam 22 having an H-shaped cross section from four directions is connected to the joint portion 14 of the steel pipe column 12 in the horizontal direction relative to the steel pipe column 12. The beam 22 is made of a steel frame and includes a vertical web 22A and flanges 22B formed above and below the web 22A. The edge of the flange 22B of the beam 22 is joined to the edge of the diaphragm 16 by welding.

  The steel pipe column 12 includes a plurality of axial bars 32 arranged in the axial direction in a position close to the inner wall of the steel pipe 30 inside the circular steel pipe 30, and along the circumferential direction outside the axial bars 32. And a plurality of shear reinforcement bars 34 arranged and arranged. The axial streaks 32 are arranged at substantially equal intervals along the inner wall of the steel pipe 30. The shear reinforcement bars 34 are arranged at regular intervals in the vertical direction. The steel pipe 30 is filled with concrete 36 with an axial bar 32 and a shear reinforcement bar 34 arranged. That is, the steel pipe column 12 is a CFT (Concrete Filled Steel Tube) column made by filling the steel pipe 30 with the concrete 36. In this embodiment, a thin steel pipe having a large diameter-thickness ratio is used as the steel pipe 30, and the axial reinforcing bars 32 and the shear reinforcing bars 34 are arranged inside. Here, the diameter-thickness ratio of the steel pipe is a value represented by D / t, where D is the diameter and t is the thickness.

  The diaphragm 16 is made of a substantially octagonal plate material, and an opening 16A through which the steel pipe column 12 passes is formed at the center. The diaphragm 16 is joined to the outer periphery of the steel pipe 30 constituting the steel pipe column 12 by welding. The octagonal edge of the diaphragm 16 is formed such that the edge 16B facing the beam 22 is short and the edge 16C between the beams 22 is long. The edge (end face) of the flange 22B of the beam 22 is abutted against and joined to the edge 16B (end face) facing the beam 22. In this embodiment, the protrusion length from the steel pipe 30 of the part (position of the edge part 16B) facing the beam 22 of the diaphragm 16 is about 200 mm.

  The outer steel pipe 18 is extrapolated by providing a clearance with the steel pipe pillar 12 (steel pipe 30) outside the steel pipe pillar 12. There is a gap between the outer steel pipe 18 and the steel pipe column 12 (steel pipe 30). The upper and lower ends of the outer steel pipe 18 are joined to the upper and lower diaphragms 16 by welding. In the present embodiment, an off-the-shelf steel pipe (for example, a diameter of 920 mm and a thickness of 9 mm) having a diameter larger than that of the steel pipe 30 (for example, a diameter of 900 mm and a thickness of 9 mm) is used as the outer steel pipe 18. The clearance between the steel pipe 18 and the steel pipe 30 is about 1 mm. The main role of the outer steel pipe 18 is reinforcement for resisting the shearing force of the joint 14 of the steel pipe column 12. The shear strength of the joint 14 can be calculated as an accumulation of the steel pipe column 12, the outer steel pipe 18, the concrete 36, and the shear reinforcement 34.

  The plate 20 has a plurality of bolt through holes 20A formed at substantially equal intervals along the vertical direction (see FIG. 1). In the vicinity of the edge of the web 22A of the beam 22, a plurality of bolt through holes 22C are formed at substantially equal intervals along the vertical direction. The two splice plates 24 that join the plate 20 and the web 22A are formed with a plurality of bolt through holes 24A in two rows along the vertical direction according to the positions of the bolt through holes 20A and the bolt through holes 22C. Has been. And the splice plate 24 is arrange | positioned in the surface contact state from these both sides in the state which face | matched the edge part (end surface) of web 22A to the edge part (end surface) of the plate 20. FIG. Further, high strength bolts 26 are inserted into the bolt through holes 20A of the plate 20, the bolt through holes 24A of the splice plate 24, the bolt through holes 22C of the web 22A, and the bolt through holes 24A of the splice plate 24, respectively, and nuts 28 from the opposite side. Are screwed together so that the plate 20 and the web 22A are frictionally joined via the splice plate 24.

  When constructing the steel pipe pillar joint portion reinforcing structure 10, first, an outer steel pipe 18 having an inner diameter larger than the outer diameter of the steel pipe 30 is extrapolated outside the steel pipe 30 which is the joint part 14 of the steel pipe pillar 12. The diaphragm 16 is provided above and below the outer steel pipe 18 of the steel pipe 30. The steel pipe 30 and the diaphragm 16 are joined by welding, and the upper and lower ends of the outer steel pipe 18 and the upper and lower diaphragms 16 are joined by welding. Further, the plate 20 is disposed between the upper and lower diaphragms 16 so as to come into contact with the diaphragm 16 and the outer steel pipe 18 corresponding to the position where the beam 22 is joined, and the plate 20 is welded to the diaphragm 16 and the outer steel pipe 18 by welding. Join.

  Next, the edges (end surfaces) of the upper and lower flanges 22B of the beam 22 are abutted against the edges 16B of the upper and lower diaphragms 16 in the joint portion 14 of the steel pipe column 12, and the web 22A of the beam 22 is aligned with the edge of the plate 20. Match the edge (end face). Then, the edge 16B of the diaphragm 16 and the flange 22B are joined by welding, and the splice plate 24 is disposed in surface contact from both sides of the plate 20 and the web 22A, and the plate 20 is connected to the plate 20 by the high strength bolts 26 and nuts 28. The web 22A is joined. The joint reinforcement structure 10 of the steel pipe column 12 is formed by such a procedure.

  Next, the operation and effect of the steel pipe column joint portion reinforcing structure 10 according to the present embodiment will be described.

  An annular diaphragm 16 is provided above and below the joint 14 of the steel pipe column 12, and the diaphragm 16 is joined to the outer periphery (steel pipe 30) of the steel pipe column 12 by welding. A cylindrical outer steel pipe 18 is inserted outside the steel pipe column 12 in the joint portion 14 with a clearance with the steel pipe 30, and the upper and lower ends of the outer steel pipe 18 are joined to the upper and lower diaphragms 16 by welding. . The flange 22B of the beam 22 is joined to the upper and lower diaphragms 16 by welding, and the plate 20 joined to the outer steel pipe 18 and the web 22A of the beam 22 are in contact with the splice plate 24 from both sides. The force bolt 26 and the nut 28 are frictionally joined. As a result, the joint portion 14 (joint portion with the beam 22) of the steel pipe column 12 joined to the beam 22 is reinforced by the outer steel pipe 18 extrapolated to the steel pipe column 12. That is, the shear strength of the joint portion 14 can be increased by reinforcing the joint portion 14 of the steel pipe column 12 from the outside by the cylindrical outer steel pipe 18.

  In the joint reinforcement structure 10 of the steel pipe column 12, the bending moment of the web 22A of the beam 22 is transmitted to the plate 20 via the splice plate 24 to which the web 22A is joined, and the fillet weld stress with the diaphragm 16 is even. It is transmitted to the diaphragm 16 by force. For this reason, the fall of the transmission efficiency to the steel pipe pillar 12 of the bending moment of the web 22A of the beam 22 by deformation | transformation etc. of the outer steel pipe 18 can be suppressed.

  In such a joint portion reinforcing structure 10 for the steel pipe column 12, it is not necessary to cut the steel pipe column 12, and the degree of processing is low. Moreover, since there is no protrusion inside the steel pipe 30 constituting the steel pipe column 12, the insertion of the axial reinforcing bars 32 and the shear reinforcing bars 34 and the filling of the concrete 36 are easy. Further, since the thickness or strength of the outer steel pipe 18 is set with respect to the design shearing force of the joint 14 of the steel pipe column 12, an efficient design is possible.

[Second Embodiment]
Next, the steel tube pillar joint reinforcement structure of the second embodiment of the present invention will be described. In addition, the same code | symbol is attached | subjected to the member same as 1st Embodiment, and the overlapping description is abbreviate | omitted.

  As shown in FIGS. 5 and 6, in the joint reinforcement structure 50 of the steel pipe column 12, the outer steel pipe 18 of the first embodiment is disposed at a position along the outer periphery of the steel pipe 30 in the joint 14 of the steel pipe column 12. Instead, a fiber reinforced plastic sheet 52 as a reinforcing member is provided. In four directions facing the beam 22 on the outer peripheral surface of the steel pipe 30, the plate 20 is joined by welding. The fiber reinforced plastic sheets 52 are respectively disposed at four locations along the outer periphery of the steel pipe 30 between the four plates 20. The fiber reinforced plastic sheet 52 includes a wall surface portion 52A joined (fixed) to the outer peripheral surface of the steel pipe 30, and a bent portion 52B in which end portions on both sides in the circumferential direction of the wall surface portion 52A are bent along the plate 20. ing. The upper end and the lower end of the wall surface portion 52 </ b> A are joined (fixed) to the diaphragm 16.

  When joining the fiber reinforced plastic sheet 52 to the outer peripheral surface of the steel pipe 30, first, as shown in FIG. 7, the reinforcing fiber sheet 60 is multilayered on the outer peripheral surface of the steel pipe 30 in the joint portion 14 of the steel pipe column 12. Affix to (two or more layers). The reinforcing fiber sheet 60 is bent so that the end portions 60B on both sides in the circumferential direction of the sheet surface 60A affixed to the outer peripheral surface of the steel pipe 30 are wound around the joint portion of the plate 20 (near the root portion of the plate 20). Temporarily adhere to the plate 20. Then, a fiber reinforced plastic sheet 52 is formed by impregnating the reinforcing fiber sheet 60 with a resin (for example, a thermosetting resin such as an epoxy resin) and curing the resin at a predetermined temperature. By impregnating and curing the reinforcing fiber sheet 60 with the resin, the wall surface portion 52A and the bent portion 52B of the fiber reinforced plastic sheet 52 are joined (fixed) to the outer peripheral surface of the steel pipe 30 and the plate 20, and the wall surface portion 52A. Are joined (fixed) to the diaphragm 16 (see FIGS. 5 and 6). As the reinforcing fiber sheet 60, for example, carbon fiber, aramid fiber, or the like is used.

  In such a joint reinforcement structure 50 of the steel pipe column 12, the fiber reinforced plastic sheet 52 is joined (fixed) to the steel pipe 30 in the joint part 14 of the steel pipe column 12, and the upper and lower ends of the fiber reinforced plastic sheet 52 are up and down. Are bonded (fixed) to the diaphragm 16, and the joint portion 14 (joint portion with the beam 22) of the steel pipe column 12 to be joined with the beam 22 is reinforced by the fiber reinforced plastic sheet 52. That is, the shear strength of the joint portion 14 can be increased by reinforcing the joint portion 14 of the steel pipe column 12 from the outside with the fiber reinforced plastic sheet 52.

  In such a joint reinforcement structure 50 of the steel pipe column 12, in addition to the effect of the first embodiment, the necessary shear strength of the joint 14 of the steel pipe column 12 can be easily made by the thickness and the number of reinforcing fiber sheets 60. There is an advantage that it can be adjusted. Moreover, compared with the conventional construction method in which the steel pipe 30 of the steel pipe column 12 is made thick and the shear strength of the joint part 14 is ensured, the housing cost (not including the diaphragm 16) of the joint part 14 is reduced by about 30 to 40%. can do.

  In the first and second embodiments, a circular steel pipe is used as the steel pipe column 12, but the present invention is not limited to this, and a square steel pipe such as a square or a hexagon may be used. In the first embodiment, when a square or hexagonal steel pipe is used as the steel pipe column 12, it is desirable that the outer steel pipe be a square or hexagonal steel pipe that is slightly larger than the steel pipe column 12.

  In the first and second embodiments, the steel pipe column 12 has the axial reinforcing bars and the shear reinforcing bars arranged therein, but the inside of the steel pipe 30 without arranging the axial reinforcing bars and the shear reinforcing bars. A structure filled with concrete may be used.

  In the second embodiment, the resin impregnated in the reinforcing fiber sheet 60 is cured to fix the fiber reinforced plastic sheet 52 to the steel pipe 30. However, the present invention is not limited to this, and the fiber reinforced plastic sheet is attached to the steel pipe 30. And the structure joined to the upper and lower diaphragm 16 with an adhesive agent may be sufficient.

DESCRIPTION OF SYMBOLS 10 Steel pipe pillar joint part reinforcement structure 12 Steel pipe pillar 14 Joint part 16 Diaphragm 18 Outer steel pipe (reinforcement member)
20 Plate 22 Beam 22A Web 22B Flange 30 Steel Pipe 32 Axial Reinforcement 34 Shear Reinforcement 36 Concrete 50 Steel Pipe Column Joint Reinforcement Structure 52 Fiber Reinforced Plastic Sheet (Reinforcement Member)
60 Fiber sheet for reinforcement

Claims (5)

A steel pipe column filled with concrete inside,
An annular diaphragm that is provided above and below the joint portion of the steel pipe column, is directly joined to the outer periphery of the steel pipe column, and a flange of the beam is directly joined;
A reinforcement member provided along the outer periphery of the steel pipe column in the joint portion, and having an upper end and a lower end joined to the diaphragm;
A plate provided on the reinforcing member and joined to a web of beams;
Reinforcement structure for steel pipe pillars   The said reinforcement member is a steel pipe pillar joint part reinforcement structure of Claim 1 which is the cylindrical outer steel pipe inserted in the outer side of the said steel pipe pillar and providing the said steel pipe pillar and clearance.   2. The steel tube column joint reinforcing structure according to claim 1, wherein the reinforcing member is a fiber-reinforced plastic sheet fixed to an outer peripheral surface of the steel tube column.   4. The steel pipe column according to claim 3, wherein the fiber reinforced plastic sheet is obtained by affixing a reinforcing fiber sheet in multiple layers on an outer peripheral surface of the steel pipe column, impregnating the resin into the reinforcing fiber sheet, and curing the resin. Joint part reinforcement structure.   The steel pipe column joint portion reinforcing structure according to any one of claims 1 to 4, wherein an axial reinforcing bar and a shear reinforcing bar are arranged inside the steel pipe column.

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