JP5021246B2 - Buckling stiffening brace - Google Patents

Description

  The present invention relates to a buckling stiffening brace used as a seismic element for a structure.

  Conventionally, seismic technology that uses steel brace material to reinforce structures such as buildings has been used. However, when steel brace material is subjected to compressive force in the axial direction, bending due to buckling occurs, resulting in steel brace. The yield strength of the material was reduced.

In order to solve the problems of steel brace materials, buckling stiffeners such as steel pipes and reinforced concrete are used to cover and reinforce the steel brace material without frictional resistance, and bending due to buckling of the steel brace material There are buckling stiffening braces that prevent deformation. (For example, see Patent Document 1)
In the buckling stiffening brace, the clearance management between the brace material and the buckling stiffening material has become a major issue. On the other hand, if the clearance is too small, the brace material expands in cross section during compression and contacts the buckling stiffener, and the compressive force is transmitted to the buckling stiffener and impairs the original function. In addition, the brace material cannot be inserted during production.

  However, in the buckling stiffening brace disclosed in Patent Document 1, when an existing brace material is used, the inner dimensions of the buckling stiffening material must be processed with high accuracy accordingly. Clearance management with stiffeners was difficult.

As a second example of the buckling stiffening brace, there is a buckling stiffening brace that adjusts the clearance between the brace material and the buckling stiffening material with a plurality of bolts screwed from the outside of the buckling stiffening material. (For example, see Patent Document 2)
However, in the buckling stiffening brace of Patent Document 2, the clearances at a plurality of locations are finely adjusted by screwing individual bolts, and a lot of construction time is required. Moreover, the head of the bolt protruded from the buckling stiffener at a plurality of locations, and the appearance of the structure was impaired.
JP-A-7-324377 JP 2000-328669 A

  The present invention has been made in view of the above facts, and an object thereof is to obtain a buckling stiffening brace that facilitates construction and clearance management.

The invention described in claim 1, and a brace member disposed obliquely into Plane, and a plurality of stiffening tube body clearance is provided between the extrapolated said brace member to the brace member, wherein One end of the stiffening cylinder that is arranged in a direction perpendicular to the axis of the brace material, has a hole into which the brace material is inserted, and is larger than the outer shape of the stiffening cylinder. A plate-like rib plate that is welded to an axial end of the other stiffening cylindrical body and joins the one stiffening cylindrical body to the other stiffening cylindrical body, and A clearance is provided between the rib plate and the brace material.

According to the above configuration, the clearance between the brace material and the stiffening cylindrical body is adjusted by the rib plate ( adjusting member ) erected from the inner wall of the stiffening cylindrical body toward the brace material. Construction is possible and clearance management becomes easy.

Further, since the rib plate is provided on the side of the stiffening cylinder, it is not necessary to change the buckled state of the brace material. Furthermore, since it is only necessary to fix the rib plate to the stiffening cylinder by welding or the like, the buckling stiffening brace can be easily constructed.

The invention according to claim 2, the rib plate is characterized by providing a plurality of locations in the axial direction of the brace.

According to the above configuration, since the rib plate is provided at a plurality of positions in the axial direction of the brace material, the deformation mode of the brace core material can be set to the second or higher deformation mode. And deformation ability is improved.

  Since the present invention has the above-described configuration, the construction of the buckling stiffening brace and the clearance management are facilitated.

  An embodiment of a buckling stiffening brace of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, a frame 13 is formed by a steel beam member 12 and a column member 14, and buckling stiffening braces 10 are attached to the frame 13 obliquely at two locations.

  The buckling stiffening brace 10 includes a brace material 16 and a steel pipe 18 that is externally inserted into the brace material 16.

  As shown in FIGS. 1 and 2, the brace material 16 is H-shaped steel, and one end is fixed to the central portion 17 of the beam member 12 by a fixing means such as a bolt and a nut (not shown), and the other end is The beam member 12 and the column member 14 are fixed to the corner 15 where they intersect.

  In this attached state, an axial force is applied to the brace material 16 when the frame 13 is deformed by an earthquake or the like.

  As shown in FIGS. 2 and 3, a rib plate 20 having a hole 24 whose inner shape is larger than the outer shape of the brace material 16 is attached to the cross section of the steel pipe 18 in the arrow Z direction and fixed by welding. Has been.

  The rib plate 20 is fixed at three locations, that is, both end portions and a central portion in the axial direction of the brace material 16.

  The dimension of the hole 24 of the rib plate 20 is processed in advance so that the vertical clearance C1 and the horizontal clearance C2 with the steel pipe 18 have predetermined values.

  Here, in the rib plate 20, the region S outside the hole 24 and inside the inner wall 22 of the steel pipe 18 becomes a region as a rib protruding from the inner wall 22 of the steel pipe 18.

  The clearances C1 and C2 differ depending on the size and material of the brace material 16 and the steel pipe 18 to be used, but have a value of several millimeters in this embodiment.

  On the other hand, the steel pipe 18 is a steel material formed in a square tube shape, and the buckling stiffening brace 10 is formed by inserting the brace material 16 in the arrow Z direction.

  Here, the outer shape of the rib plate 20 is larger than the outer shape of the steel pipe 18, and the rib plate 20 that protrudes from the steel pipe 18 at both ends of the steel pipe 18 is attached to the stopper 19 attached in the vicinity of the end of the brace material 16. By abutting, the steel pipe 18 is prevented from shifting to one end of the brace material 16.

  Next, the operation of the embodiment of the present invention will be described.

  First, the brace material 16 is manufactured according to the dimensions of the frame 13 of the structure.

  Next, a steel pipe 18 having an inner dimension larger than the outer dimension of the brace material 16 is manufactured. At this time, the clearance between the brace material 16 and the steel pipe 18 may not be considered.

  Next, the dimension of the hole 24 of the rib plate 20 is determined so that the clearance with the inner wall 22 of the steel pipe 18 is several millimeters, and three rib plates 20 are manufactured.

  Next, two rib plates 20 are welded to both ends of the steel pipe 18, respectively, and the steel pipe 18 is cut in the vertical direction at the center.

  Next, the remaining one rib plate 20 is fixed to the cross section on one side of the cut steel pipe 18 by welding, and the other side of the steel pipe 18 is fixed to one side of the steel pipe 18 by welding (see FIG. 2a). ). Thereby, the rib plate 20 is fixed to a total of three places, the both ends of the steel pipe 18, and a center part.

  Next, the brace material 16 is inserted into the steel pipe 18, and the buckling stiffening brace 10 is formed.

  The buckling stiffening brace 10 is installed obliquely on the frame 13 of the structure, and is fixed by fixing means such as bolts and nuts at the corner 15 and the center 17 (see FIG. 1).

  Here, when the frame 13 is deformed by an earthquake and a tensile force is applied to the buckling stiffening brace 10, the deformation of the frame 13 is suppressed by the tensile strength of the brace material 16.

  Further, when a compressive force is applied to the buckling stiffening brace 10, the brace material 16 tends to buckle and deform, but the steel pipe 18 suppresses the buckling deformation of the brace material 16. Buckling is prevented, and deformation of the frame 13 is suppressed by the compression strength of the brace material 16.

  As described above, the buckling stiffening brace 10 has a resistance to both a tensile force and a compressive force.

  Here, the deformation mode of the brace material 16 will be described.

  FIG. 4 schematically shows a state in which the brace material 16 stretched around the corner 15 and the center portion 17 (see FIG. 1) of the frame 13 receives a compressive force F in the axial direction and is buckled and deformed from the shaft center M. It is shown in.

  As shown in FIG. 4a, when the rib plate 20 is disposed only at the positions of both ends of the steel pipe 26, the buckling deformation of the brace material 16 becomes a primary deformation mode, and the proof stress of the brace material 16 against the compressive force. Is not so expensive.

  However, as shown in FIGS. 3 and 4b, in this embodiment, the rib plate 20 is provided in a total of three locations, both ends and the center of the steel pipe 18, and the deformation mode of the brace material 16 when a compressive force is applied. Therefore, according to Euler's buckling equation, the proof strength of the brace material 16 against the compressive force is four times or more the proof strength of the primary mode brace material 16.

  As described above, in the embodiment of the present invention, since the clearance between the brace material 16 and the inner wall 22 of the steel pipe 18 is adjusted by the rib plate 20, the construction of the buckling stiffening brace 10 and the clearance management are easy. Become.

  Further, since the rib plate 20 is provided on the steel pipe 18 side, it is not necessary to change the buckled state of the brace material 16.

  Furthermore, since the rib plate 20 is provided at a plurality of locations in the axial direction of the brace material 16, the deformation mode of the brace material 16 becomes a secondary or higher deformation mode. Will improve.

  Further, since the rib plate 20 only needs to be fixed to the brace material 16 by welding or the like, the buckling stiffening brace 10 can be easily constructed.

  In addition, this invention is not limited to said embodiment.

  The brace material 16 may be an I-shaped steel, a polygonal cross section, or a curved surface in addition to the H-shaped steel.

  Moreover, the steel pipe 18 may have a round shape or a polygonal cross section in addition to the rectangular cylinder.

  Furthermore, the rib plate 20 may have a circular cross section.

  Moreover, the position where the rib plate 20 is provided is not limited to three locations, and a plurality of three or more locations can be selected. However, it is necessary to examine the deformation mode.

It is a front view which shows the attachment state of the buckling stiffening brace which concerns on embodiment of this invention. (A) It is a fragmentary perspective view of the buckling stiffening brace which concerns on embodiment of this invention. (B) It is an axial sectional view of the buckling stiffening brace concerning the embodiment of the present invention. It is sectional drawing of the direction orthogonal to the axial direction of the buckling stiffening brace which concerns on embodiment of this invention. It is the schematic diagram which showed the deformation | transformation state of the brace which concerns on embodiment of this invention.

Explanation of symbols

10 Buckling stiffening brace (Buckling stiffening brace)
13 Frame (within the frame)
16 Brace material (Brace material)
18 Steel pipe (stiffened cylinder)
20 Rib plate (adjustment member, rib plate)

Claims (2)

A brace material arranged diagonally into the construction surface;
A plurality of stiffening cylinders extrapolated to the brace material and provided with clearances between the brace material ;
It is arranged in a direction perpendicular to the axis of the brace material, a hole is formed into which the brace material is inserted, and is larger than the outer shape of the stiffening cylinder, and is in the axial direction of the one stiffening cylinder. A plate-like rib plate that is welded to an end portion and an axial end portion of the other stiffening cylindrical body to join the one stiffening cylindrical body and the other stiffening cylindrical body;
With
A buckling stiffening brace characterized in that a clearance is provided between the rib plate and the brace material.   The buckling stiffening brace according to claim 1, wherein a plurality of the rib plates are provided in the axial direction of the brace material.

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