JP6069068B2 - Brace repair structure - Google Patents

Description

  The present invention relates to a brace repair structure in which a plastically deformed portion of a brace is excised and a remaining brace and an attached plate are joined using a fastening member.

  In Patent Document 1, reinforcement is provided in an existing steel brace material of a framework of an existing building so as to surround the brace material and extend in the longitudinal direction of the brace material to restrain buckling during compression of the brace material. A reinforcing structure is disclosed in which a material is attached and an existing brace material functions as a compression brace material.

  Further, as shown in FIG. 6, the plastically deformed flat steel brace is repaired by cutting a plastically deformed portion of the flat steel brace 100 and welding the splicing plate 101 across the cut portion.

JP 2012-62692 A

  However, the conventional brace repair structure described above has a risk of fire due to welding. Further, the reinforcing method disclosed in Patent Document 1 does not cut out a plastically deformed portion of the brace and join the accessory plate so as to straddle the cut portion.

  In view of the above circumstances, the present invention cuts out the plastically deformed portion of the brace and joins the remaining brace and the accessory plate with a fastening member, and prevents the accessory plate from being broken prior to the remaining brace. It is an object of the present invention to provide a brace repair structure that can bring out the function of the remaining brace.

  In order to solve the above problems, the brace repair structure of the present invention is a brace repair structure in which a plastically deformed portion of the brace is cut out and the remaining brace and the attached plate are joined using a fastening member. The fastening member is arranged in a staggered manner with a predetermined pitch in two rows, and the first fastening member disposed at the position closest to the end of the attachment plate is the remaining brace. One is arranged at the center in the width direction.

  In the load transmission at the repaired portion of the brace, the load is transmitted to other fastening members after the first fastening member disposed at the position closest to the end of the attachment plate receives a large load. One of the first fastening members is disposed at the center in the width direction of the remaining brace, and has a larger edge than the edges of the two rows of zigzag fastening members. The load is transmitted to the two rows of zigzag fastening members, and the load is received by all the fastening members. As a result, the breakage due to the border is less likely to occur, and the accessory plate can be prevented from breaking prior to the remaining brace to bring out the function of the remaining brace.

  A second fastening member is disposed next to the end of the attachment plate next to the first fastening member, and the edge of the second fastening member is larger than the edge of the fastening member arranged in a staggered manner. It may be a length. According to this, a long edge is set also in the second fastening member, and the destruction of the remaining brace hardly occurs.

  The second fastening member may be located on one of the two rows. According to this, the edge of the second fastening member is the same as the edge of the fastening member arranged in a staggered manner, and one row in the staggered arrangement is started from the second fastening member.

  The distance between the first fastening member and the second fastening member and the distance between the second fastening member and the fastening members arranged in a staggered manner closest to the second fastening member may be larger than the predetermined pitch. According to this, it becomes difficult to produce the crack between the fastening members of the location where the said 1st fastening member and the said 2nd fastening member are arrange | positioned, and it becomes easy to receive a load with all the fastening members.

  The fastening member may be a screw. When a bolt is used as the fastening member, a large cross-sectional defect due to the bolt hole occurs. However, when the screw is used, such a large cross-sectional defect can be avoided.

  According to the present invention, the plastically deformed portion of the brace is excised and the remaining brace and the accessory plate are joined using a fastening member, and the accessory plate is prevented from being broken prior to the remaining brace. There is an effect that the function of the remaining brace can be brought out.

It is the figure which showed the brace repair structure concerning embodiment of this invention, The figure (A) is a top view, The figure (B) is a front view. It is explanatory drawing which showed the example of screw arrangement | positioning dimension in the brace repair structure of FIG. 3 is a graph showing the tensile strength (stress-strain diagram) of the brace repair structure of FIG. 1, the first comparative example, the second comparative example, and the brace alone. It is explanatory drawing which showed the screw arrangement | positioning dimension in a 1st comparative example. It is explanatory drawing which showed the screw arrangement | positioning dimension in a 2nd comparative example. It is explanatory drawing which showed the prior art example.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
As shown in FIG. 1, the brace repair structure of this embodiment is a structure in which a plastically deformed portion of the flat plate brace 1 is cut out and the remaining brace 1A and the accessory plate 2 are joined using screws 3 as fastening members. is there. In this embodiment, the material of the flat brace 1 and the material of the accessory plate 2 are the same. The flat brace 1 has a width of 50 mm, and the splicing plate 2 has a width of 50 mm. The thickness of the accessory plate 2 is larger than the thickness of the flat plate brace 1. In this embodiment, the thickness of the flat plate brace 1 is 4.5 mm, and the thickness t of the splicing plate 2 is 6.0 mm.

  Further, as an example, a pilot hole 2a is formed in advance in the place of the splicing plate 2 into which the screw 3 is screwed, and the screw 3 is screwed into the pilot hole 2a so that the distal end side of the screw 3 becomes the remaining brace. Screwed into 1A. The screw 3 is made of, for example, iron and has a nominal diameter of 6 × length of 19 mm.

  As shown in FIG. 2, the length from the end of the attachment plate 2 to the position of the innermost screw 3 to be joined to one of the remaining braces 1A is set to 152 mm. The length to the location of the first screw 3A is set to 24 mm. The length of the attachment plate 2 is, for example, a length obtained by adding the length of the cut portion and the length twice the 24 mm to the length obtained by doubling the 152 mm.

  The arrangement of the screws 3 is a staggered arrangement with a predetermined pitch in two rows. In this embodiment, the total number of the screws 3 is 10, and the predetermined pitch is set to 12 mm. The arrangement interval of the screws 3 in each row is 24 mm. The interval between the rows is set to 16 mm, each row is located 8 mm away from the center in the width direction, and the distance (edge margin) between each row and the edge of the remaining brace 1A is set to 17 mm. The interval between the rows may be set to approximately 1/3 of the width of the remaining brace 1A (for example, within ± 10% of 1/3).

  The first screw 3A disposed at the position closest to the end of the accessory plate 2 is disposed at the center in the width direction of the remaining brace 1A. The perforation of the first screw 3A is 25 mm, and the perforation is 24 mm.

  The edge of the second screw 3B arranged next to the first screw 3A next to the end of the splicing plate 2 is set to be larger than the edge of the screw 3 arranged in a staggered manner (17 mm). . That is, in this embodiment, the edge of the second screw 3B is 17 mm or more and 25 mm or less, and the edge when the second screw 3B is positioned on one of the two rows is 17 mm. Become.

  In this embodiment, the distance between the first screw 3A and the second screw 3B is 22 mm, which is larger than a predetermined pitch (12 mm). The distance between the second screw 3B and the staggered screw 3 that is closest to the second screw 3B is also 22 mm, which is larger than the predetermined pitch (12 mm).

  FIG. 4 shows the repair structure of Comparative Example 1. In Comparative Example 1, the thickness t of the accessory plate is 4.5 mm, which is the same as the thickness of the brace. Further, as shown in the figure, the pitch of the screws (prepared holes) arranged in a staggered manner in two rows is set to 12 mm, and the pitch in each row is 24 mm. And the end opening of the said screw (lower hole) is 24 mm, and the edge opening is 13 mm. The number of the screws (prepared holes) is twelve. The spacing between the rows is 24 mm.

  FIG. 5 shows the repair structure of Comparative Example 2. In Comparative Example 2, the thickness t of the accessory plate is 6.0 mm. Further, as shown in the figure, the pitch of the screws (prepared holes) arranged in a staggered manner in two rows is set to 12 mm, and the pitch in each row is 24 mm. The distance between the first screw closest to the end of the attachment plate 2 and the second screw closest to the next is set to 22 mm, and the staggered arrangement of the second screw and the closest screw is arranged. The distance from the screw is 22 mm. Further, the perforation of the screw (the lower hole) is 24 mm, and the perforation is 13 mm. The number of the screws (prepared holes) is twelve.

  FIG. 3 shows the repair structure according to the embodiment of FIG. 1, the comparative example 1, the comparative example 2, and the tensile strength test result (stress-strain diagram) of the brace 1 itself. According to this test result, it was found that the repair structure according to the example obtained higher strength than the comparative example 1 and the comparative example 2. In the repair structure according to the example, the screw portion of the remaining brace 1A was cracked at the location indicated by the dotted line in FIG. Moreover, in the said comparative example 1, the attachment board cracked in the location shown with the dotted line in FIG. 4, and in the said comparative example 2, the screw part of the residual brace cracked in the location shown with the dotted line in FIG. In other words, in the first comparative example, the accessory plate yields before the remaining brace yields, and in the second comparative example, the yield is generated by cracking from the position of the screw arranged at the position closest to the end of the accessory plate. Occurred.

  In the repair structure shown in FIG. 1, the load is transmitted to the other screws 3 after the first screw 3 </ b> A arranged at the position closest to the end of the accessory plate 2 receives a large load. The first screw 3A is arranged at the center in the width direction of the remaining brace 1A, and has a larger edge than the two rows of the staggered screws 3, so The resulting destruction is less likely to occur. The load is transmitted to the two rows of staggered screws 3 and received by all ten screws 3. As a result, the breakage due to the border is less likely to occur, and the accessory plate 2 is prevented from breaking before the remaining brace 1A to bring out the function of the remaining brace 1A (the remaining brace 1A is sufficient). Can exhibit plastic elongation). In addition, the repair structure of this embodiment can reduce the number of screws from 12 to 10 compared to the first and second comparative examples.

  The second screw 3B is disposed at a position near the end of the splicing plate 2 next to the first screw 3A, and the edge of the second screw 3B is larger than the edge of the screw 3 arranged in a staggered manner. If so, the second screw 3B is also set to have a long edge, and the remaining brace 1A is less likely to break from the screw portion.

  When the second screw 3B is positioned on one of the two rows, the edge of the second screw 3B is the same as the edge of the screw 3 arranged in a staggered manner, and the second One row in the staggered arrangement is started from the screw 3B.

  If the distance between the first screw 3A and the second screw 3B and the distance between the second screw 3B and the screw 3 arranged in the staggered manner are larger than the predetermined pitch, the first screw 3A In addition, cracks between screws at the positions where the second screws 3B are disposed are less likely to occur, and all the screws 3 are likely to receive a load.

  A bolt may be used as the fastening member, but in this case, a cross-sectional defect due to the bolt hole occurs. When the screw 3 is used, such a cross-sectional defect does not occur, so that a higher repair strength can be obtained.

  As mentioned above, although embodiment of this invention was described with reference to drawings, this invention is not limited to the thing of embodiment shown in figure. Various modifications and variations can be made to the illustrated embodiment within the same range or equivalent range as the present invention. For example, the present invention can be applied not only to a tension brace but also to a compression brace (L-shaped steel, angle steel, square steel pipe, steel pipe).

1 Flat Brace 1A Remaining Brace 2 Attached Plate 2a Pilot Hole 3 Screw (fastening member)
3A First screw (first fastening member)
3B Second screw (second fastening member)

Claims (5)

It is a brace repair structure in which a plastically deformed portion of the brace is excised and the remaining brace and the attached plate are joined using a fastening member,
The thickness of the attachment plate is thicker than the thickness of the brace,
The arrangement of the fastening members is a staggered arrangement with a predetermined pitch in two rows,
A brace repair structure characterized in that one first fastening member disposed at a position closest to the end of the attachment plate is disposed at the center in the width direction of the remaining brace.   2. The brace repair structure according to claim 1, wherein a second fastening member is disposed at a position close to an end of the attachment plate next to the first fastening member, and the edge of the second fastening member is formed in the staggered manner. A brace repair structure characterized in that it is longer than the edge of the fastening member arranged.   3. The brace repair structure according to claim 2, wherein the second fastening member is located on one of the two rows.   4. The brace repair structure according to claim 2, wherein an interval between the first fastening member and the second fastening member and the second fastening member and the staggered fastening member closest to the second fastening member are provided. A brace repair structure characterized in that the interval is larger than the predetermined pitch.   The brace repair structure according to any one of claims 1 to 4, wherein the fastening member is a screw.

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