JP5740220B2 - Seismic reinforcement structure for roof frame - Google Patents

Description

  The present invention relates to a seismic reinforcement structure for a roof covering a relatively large area such as a gymnasium in a school.

For example, a gymnasium is a place used by school officials for physical education classes, club activities, school events, etc., and in the event of an emergency disaster, it plays a role as an emergency evacuation site for local residents. It is a facility.
In recent years, the occurrence of large-scale earthquakes has become a reality, and on the other hand, it has been pointed out that school gymnasiums do not meet the latest earthquake resistance standards, and there is a need for immediate implementation of earthquake-resistant construction.

  As for seismic reinforcement of roofs for gymnasiums, etc., the diagonal direction of beams orthogonal to the lattice pattern is reinforced with braces with steel bars, and the brace is fixed to the beams by a special method, thereby reducing the number of components and construction management. A technique for facilitating the above has been proposed (Patent Document 1).

JP 2008-267022 A

The technique proposed in Patent Document 1 has the effect of reducing the number of component parts and facilitating construction management as compared with the conventional technique in which the members are joined mainly by welding.
However, there is no difference from the prior art in that braces are arranged in each grid, and the number of grids is increased, which is insufficient in reducing the number of parts and reducing the burden on construction management.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a seismic reinforcement structure for a roof frame that can improve seismic performance, reduce the number of members, and shorten the construction period.

The seismic reinforcement structure for a roof frame according to the present invention is a seismic reinforcement structure that enhances the earthquake resistance of a building, and extends in one direction in the roof frame and is parallel to each other and in a direction perpendicular to the one direction. Each diagonal of a rectangular grid formed by two beams extending and parallel to each other is connected by a tendon. The grid extends across at least one other beam which extends in a direction orthogonal to the other beam and the direction extending in the one direction.

The tendon is composed of a PC steel strand , a first sleeve having one end fixed to one of the corners of the grid and one end of the wire fixed to the other end, and an opening on one end. A first sleeve having a first female screw and a second sleeve having the other end fixed to the other end, and a first male screw screwed into the first female screw on one end side. A screw rod provided with a second male screw on the other end side, a through hole extending in the axial direction, and a second female screw provided on the inner peripheral side of the through hole. An adjuster in which the second male screw inserted from one of the directions is screwed together to connect the screw rod, and the third male screw is provided on the other end side in the axial direction, and one end side The third male screw is screwed into a third female screw that opens to connect the adjuster, and the other end of the corner of the grid A clevis fixed diagonally.

The tendon is formed so as to adjust the tension of the tendon by rotating the adjuster about its axis.
Here, the “roof frame” refers to a frame extending in the direction of the roof surface formed by large beams, small beams, roof surface braces, and the like on the roof surface of the building.
Further, "the grid, said at least one of straddled ingredients other beams and other beam extending in a direction perpendicular to said one direction extending in one direction," and, in other words, (linked cable) It means that one of at least one of two orthogonal beams crosses the grid.

In the present invention, the use of a PC stranded wire as the tendon material results in a large internal stress immediately without initial elongation, and the deformation of the roof frame due to an earthquake or the like can be minimized.
Preferably, a beam in which one side of the rectangular grid is connected to a column .
Good Mashiku is linear than the PC steel is galvanized products.

  ADVANTAGE OF THE INVENTION According to this invention, the earthquake-proof reinforcement structure for roof surface frames which can improve earthquake resistance, can reduce the number of members, and can shorten a work period can be provided.

FIG. 1 is a schematic view of a cable used in an earthquake-proof reinforcement structure for a roof frame. FIG. 2 is a schematic view of an extrusion type sleeve. FIG. 3 is a schematic view of a screw rod. FIG. 4 is a schematic view of the adjuster. FIG. 5 is a schematic view of the first clevis. FIG. 6 is a schematic view of the second clevis. FIG. 7 is a connection diagram of the first screw rod, the adjuster, and the first clevis. FIG. 8 is a schematic view of the pin. FIG. 9 is a diagram in which a seismic reinforcement structure is adopted for the gable roof. FIG. 10 is a view showing a state where a cable fixing gusset plate is fixed to a beam or the like by welding. FIG. 11 is a view showing a state in which the fixing bracket integrated with the gusset plate is fixed to the beam or the like with a bolt. FIG. 12 is a view showing the arrangement of the stiffeners. FIG. 13 is a diagram showing a conventional structure for seismic reinforcement. FIG. 14 is a diagram comparing the scaffold during construction of the seismic reinforcement structure with a scaffold having a conventional structure. FIG. 15 is a schematic view of the roof structure of an existing gymnasium that is an object of seismic reinforcement. FIG. 16 is a plan view of a seismic reinforcement structure by a field welding type. FIG. 17 is a plan view of a conventional seismic reinforcement structure using a field welding type. FIG. 18 is a diagram showing a seismic reinforcement structure for a kamaboko roof.

  FIG. 1 is a schematic view of a cable 2 used in a seismic reinforcement structure 1 for a roof frame, FIG. 2 is a schematic view of an extrusion-type sleeve 11, FIG. 3 is a schematic view of screw rods 12 and 16, and FIG. FIG. 5 is a schematic diagram of the first clevis 14, FIG. 6 is a schematic diagram of the second clevis 15, FIG. 7 is a connection diagram of the first screw rod 12, adjuster 13 and first clevis 14, and FIG. FIG.

3A is a schematic diagram of the first screw rod 12, FIG. 3B is a schematic diagram of the second screw rod 16, FIG. 4A is a left side view of FIG. 5B, and FIG. ) Is a view of (a) as viewed from above.
The cable 2 comprises a PC steel stranded wire 18, two extrusion-type sleeves 11, 11, a first screw rod 12, an adjuster 13, a first clevis 14, a second clevis 15, and a second screw rod 16.

PC steel strand 18 is obtained by heating a piano wire to 900 ° C. or higher and then cooling it under certain conditions (patenting), drawing and twisting by cold working, and removing residual strain by bluing. The PC steel strand 18 has no initial elongation with respect to the external force (tensile force) and immediately generates a large internal stress.
For the cable 2 used in the seismic reinforcement structure 1 for a roof frame, a PC steel strand 18 in which strands galvanized are combined together is used. The galvanized PC steel strand 18 is excellent in corrosion resistance. The seismic reinforcement structure 1 for a roof frame may be exposed depending on the building, and in order to further improve the anticorrosion performance and improve the appearance, a PC steel stranded wire coated with high-density polyethylene (PE) that can be colored. Can also be used.

The extrusion sleeve 11 has a columnar appearance, and a PC steel wire 18 is firmly connected to one end side thereof. On the other end side, a female screw 21 that opens to the end face is provided. The extrusion-type sleeves 11 and 11 are connected to both ends of the stranded wire 18 by a crimping process.
The first screw rod 12 is for connecting the extrusion sleeve 11 and the first clevis via the adjuster 13. The first screw rod 12 has a round bar shape as a whole, and is provided with a short male screw 22 that is screwed into the female screw 21 of the extrusion sleeve 11 on one end side. The first screw rod 12 is provided with a long male screw 23 in a range exceeding one third of the length of the first screw rod 12 from the other end. The first screw rod 12 includes flat portions 24 that are flat at intervals of 90 degrees in the circumferential direction so that they can be fixed with a wrench opening in the vicinity of the short male screw 22.

The first screw rod 12 has a short male screw 22 screwed into a female screw 21 of the extrusion-type sleeve 11 and is connected to a PC steel strand 18.
The adjuster 13 has a through hole 28 in the axial direction, and its shape is cylindrical as a whole. The adjuster 13 has a larger outer diameter in the vicinity of both ends than in other portions. A portion where the outer diameter is increased near one end is provided with a male screw 25 on its outer periphery, an inner diameter is smaller than the other portion of the through hole 28 and a female screw 26 is provided on the inner periphery (female). The valley diameter of the screw 26 is smaller than the inner diameter of the other part of the through hole 28).

The portion of the adjuster 13 where the outer diameter is increased near the other end is provided with flat engagement surfaces 27, 27, 27, 27 at intervals of 90 degrees in the circumferential direction so as to be able to rotate by being engaged with the opening of the spanner. It has been.
In the adjuster 13, the long male screw 23 of the first screw rod is inserted into the through hole 28 from the side opposite to the side where the male screw 25 is provided, and the tip of the long male screw 23 is screwed into the female screw 26. The first screw rod 12 is connected.

The first clevis 14 has a substantially cylindrical appearance and includes a holding portion 31 and a support portion 32.
The holding portion 31 has a cylindrical shape having a hole 33 in the axial direction, and a female screw 34 in which a half of the length of the hole 33 from the end surface where the hole 33 opens is screwed into the male screw 25 of the adjuster 13. It has become. The inner diameter of the less than half of the back side of the hole 33 is substantially equal to or slightly smaller than the mountain diameter of the male screw 25 and larger than the mountain diameter of the long male screw 23 of the first screw rod 12. .

Strictly speaking, the holding portion 31 has a truncated cone shape in which the outer diameter of the opening portion of the hole 33 is approximately one half of the length, and the outer diameter is smaller toward the opening side.
The support portion 32 is U-shaped, so-called “clevis”, and two plate-like arm portions 35, 35 forming the U-shape extend outward in the axial direction of the hole 33. The arm portions 35, 35 are provided with pin holes 36, 36 penetrating in a direction in which they face each other (a direction perpendicular to the plate).

Referring to FIG. 7, the first clevis 14 has an adjuster 13, a first screw rod 12, and an extrusion die by screwing the male screw 25 of the adjuster 13 connected to the long male screw 23 into the vicinity of the opening of the female screw 34. A PC steel strand 18 is connected via a sleeve 11.
Here, when viewed from the left side of FIG. 5, the adjuster 13 is rotated to the right with the first clevis 14 and the first screw rod 12 prevented from rotating. The first screw rod 12 is pulled into the hole 33 while moving to.

That is, the first clevis 14, the adjuster 13, and the first screw rod 12 connected to each other can adjust the connection length thereof, that is, the length of the cable 2 by rotating the adjuster 13.
The long male screw 23 of the first screw rod and the female screw 26 of the adjuster 13 screwed to the first screw rod that perform such an operation are reverse screws (left screws).

The second clevis 15 includes a connecting portion 37 and a support portion 38. The connection part 37 has a truncated cone in appearance, and has a female screw 39 that opens to the end face on the side having a smaller diameter.
The support portion 38 has the same shape as the support portion 32 of the first clevis 14, the arm portions 40, 40 corresponding to the arm portions 35, 35 of the first clevis 14, and the pin holes 41 provided in the arm portions 40, 40. , 41.

The second screw rod 16 is a stud that is provided with a screw thread (male screw 42) throughout.
The second clevis 15 has one end of the second screw rod 16 screwed into the female screw 39, and the other end of the second screw rod 16 is connected to the end of the PC steel stranded wire 18 on the side opposite to the first clevis 14. The cable 2 is formed by being screwed into the female screw 21 of the connected extrusion-type sleeve 11.
The pin 17 penetrates the pin hole 36 of the first clevis 14 and the pin hole 41 of the second clevis 15 to fix the first clevis 14 and the second clevis 15 to the roof beam of the building. The pin 17 includes a central cylindrical body 45 and male screws 46 on both axial sides of the body 45.

For example, the pin 17 has a gusset plate fixed to the beam of the building between the arm portions 35 and 35 of the support portion 32 of the first clevis 14, and a pin concentric hole that penetrates the pin holes 36 and 36 and the gusset plate. By passing through the body 45 and screwing nuts into the male threads 46, 46 at both ends, it contributes to attachment of one end of the cable 2 to the beam of the building.
By the way, on the roof of an existing gymnasium or the like, a plurality of beams are provided in each of the beam running direction and the beam-to-beam direction, and a large number of portions (grids) surrounded by orthogonal beams are formed. As for the earthquake resistance of the roof, many of the rectangular grids satisfy the earthquake resistance standards at the time of construction as a whole by connecting the intersections of the beams positioned diagonally with braces. However, such old buildings do not meet the latest revised seismic standards.

The seismic strengthening structure 1 is to obtain the strength satisfying the latest seismic standards alone by constructing it below the roof structure that does not satisfy the existing seismic standards of the building.
FIG. 9 shows an example in which the seismic reinforcement structure 1 is adopted for a gable roof widely used in a school gymnasium or the like. The seismic reinforcement structure 1 on the gable roof has a beam direction (see FIG. 9) by means of beams (sometimes referred to as “large beams”) 51,..., 51 extending in the direction between the beams (Y direction in FIG. 9). Are divided into a plurality of rectangular grids and are connected by cables 2 and 2 that intersect diagonals of the grids.

The grid newly set in the seismic reinforcement structure 1 is an existing grid defined by beams 51,..., 51 extending in the inter-beam direction Y and small beams 57,. (In FIG. 9, the direction Y between the beams) is a size straddling a plurality. For a specific direction, one or a plurality of small beams 57 perpendicular to this direction are jumped (in FIG. 9, two small beams 57,
57 is formed).

Each apex portion of the rectangular grid to which the cable 2 is connected is referred to as a “fixing portion”, and the fixing portions in FIG. 9 are denoted by reference numerals 52a, 52b, 53a, and 53b.
.., 51 forming a grid in the seismic reinforcement structure 1, the top girder beam 54 at the top of the gable orthogonal to the girder 51,... 51, and the column head girder beam connected to the columns 55,. For 56, an existing one is used.

  The grid is preferably a column head girder beam 56 in which at least one of the four sides is connected to the column 55. When any one side is a beam (column head girder beam 56) connected to the column 55, the “specific direction” is a direction orthogonal to the beam. In the seismic reinforcement structure 1 shown in FIG. Any two of the four fixing portions 52a, 52b, 53a, and 53b in the grid are also supported by the pillars.

When the space between the large beams 51 is close, or when there is no problem with the strength after seismic reinforcement, a grid to which the diagonal lines of the cables 2 and 2 are connected is also formed by jumping (stranding) the large beams 51. can do.
The first clevis 14 and the second clevis 15 are both attached to the gusset plate 61 so as to be rotatable in the direction X of the rows by pins 17. “Rotation in the column direction X” means rotation about an axis perpendicular to the plane including the intersecting cables 2 and 2.

Each of the cables 2 attached to the building is adjusted by the adjuster 13 so that its tension is within a predetermined range. However, in the earthquake-proof reinforcement structure 1, the initial tension of the cable 2 at the time of construction is extremely small.
In the seismic reinforcement structure 1, deformation of the roof frame is suppressed by tensile stress generated in the cables 2 and 2 when a force is applied to deform the roof frame due to an earthquake or the like. The PC steel strand 18 used for the cable 2 has a characteristic that a large internal stress is generated at a stage where the elongation is small. Therefore, the seismic strengthening structure 1 can minimize the deformation of the roof frame due to earthquakes, etc., and prevent the destruction of the joint between the beam and the beam and the joint between the beam and the column, including the existing roof structure. Is done.

Moreover, in the earthquake-proof reinforcement structure 1, since the deformation of the roof is suppressed during the swing and the entire roof moves like a single plate, the force is evenly distributed to each cable 2 and the deformation of each pillar is also uniformed. Reduce the risk of building collapse.
FIG. 10 is a view showing a state in which a gusset plate 61 for fixing the cable 2 is fixed to the large beam 51 and the like by welding, and FIG. 11 is an illustration of the fixing brackets 62 and 63 integrated with the gusset plate 61 by bolts. FIG. 12 is a diagram showing the arrangement of the stiffeners 64. FIG.

The seismic reinforcement structure 1 can attach the cable 2 to the large beam 51 of the existing roof by either welding or bolts.
In the attachment of the cable 2 by welding as shown in FIG. 10, the gusset plate 61 can be directly connected to the girder 51 or the like, so that the cost of fittings and the like necessary for coupling can be reduced at a low cost. Reference numeral 64 in FIG. 10 is a stiffener. The stiffener 64 is disposed in the fixing portions 52a, 52b, 53a, 53b of the cable 2 when the strength of the building before the seismic reinforcement is insufficient with respect to the seismic reinforcement work.

In the structure shown in FIG. 11 in which the construction of the cable 2 is carried out with bolts using the fixing metal fittings 62 and 63, there is a disadvantage that the number of parts is increased as compared with the construction by welding. It is limited to the drilling of bolts for large beam webs, etc., which reduces work and shortens the construction period.
The seismic reinforcement structure 1 using the cable 2, for example, disclosed in Japanese Patent Application Laid-Open No. 2008-267022, divides the roof into a number of grids, and connects the diagonals of the grids with braces 91 made of steel bars and steel molds. Compared with the conventional method (refer FIG. 13) to improve, the length of each grid becomes large and the number of members, such as a gusset plate required for every grid, can be reduced significantly.

The stiffener 64 can also be used to fix the brace when the diagonal strength of each grid is connected by a brace 91 made of steel bar and mold steel to improve seismic resistance (FIG. 13). It is necessary to arrange in the part 92, ..., 92. Since the seismic reinforcement structure 1 has fewer fixing portions 52a, 52b, 53a, and 53b than the conventional method, the amount of the stiffener 64 can be reduced.

As described above, the seismic reinforcement structure 1 using the cable 2 can suppress the increase in the roof weight (building weight) after the earthquake resistance by greatly reducing the number of members, and the building (roof) weight increases. The deterioration of earthquake resistance caused by
FIG. 14 is a diagram comparing the scaffold 71 during construction of the earthquake-proof reinforcement structure 1 with a scaffold 93 having a conventional structure. (A) of FIG. 14 is an earthquake-proof reinforcement structure 1 and (b) is a conventional structure.

The seismic reinforcement structure 1 is divided only by the beam 51 in the inter-beam direction Y, divided into a plurality of rows in the column direction X, and is connected to each vertex of the grid (fixing portions 52a, 52b, 53a, 53b) long in the inter-beam direction Y. Two or two constructions are performed. Therefore, in the seismic reinforcement structure 1, the fixing work of the cable 2 is limited to the positions of the top girder beam 54 and the column head girder beam 56.
On the other hand, in the conventional structure, braces 91 and 91 are applied to the grid defined by the beam 51 in the inter-beam direction Y and the small beam 57 in the column direction X. Therefore, in the conventional structure, the bracing 91,..., 91 is fixed at the positions of the small beams 57 and 57 extending in the column direction X in addition to the top beam beam 54 and the column head beam beam 56.

  As can be seen from FIGS. 14A and 14B, the seismic reinforcement structure 1 has fewer fixing portions 52a, 52b, 53a, and 53b of the cables 2 and 2 in the beam-to-beam direction Y than the conventional structure. For this reason, it is possible to significantly reduce the number of places where the scaffold 71 is disposed as compared with the conventional structure. In the earthquake-proof reinforcement structure 1, the work of installing and removing the scaffold is reduced, and also in this respect, the construction period can be shortened and the cost can be reduced.

  Table 1 compares the seismic reinforcement structure 1 in the existing gymnasium roof and the conventional method.

  FIG. 15 is a schematic diagram of the roof structure of an existing gymnasium that is an object of seismic reinforcement, FIG. 16 is a plan view of the seismic reinforcement structure 1 by the field welding type, and FIG. 17 is a plan view of the conventional earthquake resistance reinforcement structure by the field welding type. Table 1 is obtained by integrating the member quantity, member weight, and material cost for the structure in FIGS. 16 and 17. In addition, material construction cost shows the ratio with respect to this amount by making the amount of a conventional structure into 100.

The outline of the existing gymnasium that is subject to seismic reinforcement is as follows.
(1) Frame type: Pure steel structure (2) Floors: 2 floors above ground (3) Building height: eave height 14.45m, maximum height 18.95m
(4) Structure type in the column direction: 1st floor to ramen structure, 2nd floor to brace structure Overall length in the column direction: 40m (5m x 8 spans)
(5) Structural type in the inter-beam direction: Ramen structure Total length in the inter-beam direction: 30m (15m x 2 spans)
The seismic reinforcement structure 1 uses 15.2 mm PC steel strands from 7 galvanized wires, and 16φ round steel braces are used in the conventional structure, and both are assumed to be reinforced with 125 x 125 x 4.5 stiffeners. .

Although it is a trial calculation under limited conditions, from Table 1, the seismic reinforcement structure 1 can perform equivalent seismic reinforcement with approximately 30% in terms of the number of members and approximately 40% in terms of the weight of the member compared to the conventional structure. The material cost is approximately 80% of that of the conventional structure, which is superior to the conventional structure in terms of material cost and construction period.
For buildings (existing gymnasiums) of the size described above, the grid in the seismic reinforcement structure 1 does not use the small beam 57, but the large beams 51,..., 51, the top girder beam 54, and the column head girder beam. 56 and 56 are used.

FIG. 18 is a diagram showing an outline of seismic reinforcement for the kamaboko roof. In FIG. 18, (a) is a seismic reinforcement structure 1B, and (b) is a conventional structure.
In the kamaboko roof, the beams 51B,..., 51B extending in the inter-beam direction Y are curved in an arch shape. The kamaboko roof has a top girder beam 54B extending in the column direction X at the maximum height position, a column head girder beam 56B extending in the column direction X and connected to the column, and a top girder beam 54B and a column head girder orthogonal to the main beam 51B. A roof surface frame is formed by the small beams 57B,..., 57B extending in the column direction X with the beam 56B.

The seismic reinforcement structure 1B for the roof surface frame of the kamaboko roof is seismically reinforced by the cables 2, ..., 2 in the same manner as the seismic reinforcement structure 1 for the gable roof.
The grid newly constructed with the seismic reinforcement structure 1B shown in FIG. 18A is elongated in plan view in which the top girder beam 54B and the column head girder beam 56B are opposed short sides in a rectangle. The grid in the earthquake-proof reinforcement structure 1B is formed by jumping the small beams 57B and 57B extending in the column direction X. Even in the kamaboko roof, in the seismic reinforcement structure 1B, a grid is formed in a state in which one or a plurality of small beams 57B extending in a direction perpendicular to this direction in a specific direction (the inter-beam direction Y in FIG. 18) are straddled. .

The grid in the kamaboko roof seismic reinforcement structure 1B is preferably a column head girder beam 56B in which at least one of the four sides of the rectangle is connected to the column 55.
The seismic reinforcement structure 1B of the kamaboko roof moves as a whole as a single board when the roof frame is shaken by an earthquake, the force is evenly distributed to each cable 2, and the deformation of each column is also uniform. To prevent the building from collapsing.

Moreover, the seismic reinforcement structure 1B not only has a small number of members and suppresses an increase in the weight of the roof, but also has a small work amount for seismic reinforcement and simplifies installation and removal of the scaffold.
In FIG. 18, the same reference numerals as those in FIGS. 12 and 13 are the same as those in FIGS.
In the above-described embodiment, even if a wire rope or a steel bar that does not have initial elongation and immediately generates a large internal stress is used instead of the PC steel wire, the material construction cost and the construction period are more than the conventional structure. A superior seismic reinforcement structure can be obtained. When steel bars are used, the degree of tension of the steel bars is adjusted by turnbuckles.

In addition, the span in the column direction X can be arbitrarily set depending on the structure of the building to be seismically reinforced. The fixing brackets 62 and 63 of the cable 2 can be attached to various parts such as the lower flange or web of the column head girder beam 56, and the method of attachment can be selected from on-site welding or bolt joining.
In addition, each structure or overall structure, shape, size, number, material, and the like of the earthquake-resistant reinforcement structures 1 and 1B and the earthquake-resistant reinforcement structures 1 and 1B can be appropriately changed in accordance with the spirit of the present invention.

  INDUSTRIAL APPLICABILITY The present invention can be used for a seismic reinforcement structure for a roof covering a relatively large area such as a gymnasium in a school.

1,1B Seismic reinforcement structure 2 Tension material (cable)
11 A part of the first sleeve, the second sleeve (extrusion type sleeve)
12 Screw rod (first screw rod)
13 Adjuster
14 Clevis (first clevis)
15 Part of the first sleeve (second clevis)
16 Part of the first sleeve (second screw rod)
18 PC steel strand
21 First female screw (female screw)
22 First male screw (short male screw)
23 Second male screw (long male screw)
25 Third male screw (male screw)
26 Second female screw (female screw)
28 Through hole
34 Third female screw (female screw)
51, 51B Large beams (beams extending in the direction between the beams)
52a, 53b Grid diagonal 53a, 52b Grid diagonal 54, 54B Beam (top girder beam)
55 Column 56, 56B Beam (column head beam)
57, 57B Beam (small beam)

Claims (3)

A seismic reinforcement structure that enhances the earthquake resistance of buildings,
The diagonals of the rectangular grid formed by the two beams extending in one direction and parallel to each other and the two beams extending in the direction orthogonal to the one direction and connected in parallel to each other in the roof frame are connected by a tension material. And
The grid straddles at least one of the other beams extending in the one direction and the other beams extending in a direction orthogonal to the one direction;
The tendon is
PC steel stranded wire,
A first sleeve having one end fixed to one of the corners of the grid and one end of the wire fixed to the other end;
A second sleeve provided with a first female screw that opens on one end side and the other end of the wire fixed on the other end side;
A screw rod having a first male screw threadedly engaged with the first female screw provided on one end side and a second male screw provided on the other end side;
A through-hole penetrates in the axial direction, and the second male screw inserted from one side in the axial direction is screwed into a second female screw provided on the inner peripheral side of the through-hole so that the screw rod is An adjuster connected and provided with a third male screw on the other end side in the axial direction;
The third male screw is engaged with a third female screw opened on one end side to connect the adjuster, and the other end side has a clevis fixed to the diagonal of the corner of the grid. And
An anti- seismic reinforcement structure for a roof frame, wherein the adjuster is rotated about its axis to adjust the tension of the tendon. The seismic reinforcement structure for roof surface frames according to claim 1, wherein one side of the rectangular grid is a beam connected to a column. The seismic reinforcement structure for a roof structure according to claim 1 or 2, wherein the wire is a galvanized product .

Images