JP2007132108A - Seismic response control brace structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a seismic response control brace structure which can be easily incorporated into a brace member, which has high structural safety, and which can efficiently absorb vibration energy. <P>SOLUTION: The seismic response control brace structure 1 is provided with the brace member 5 made of a tension material, a fastening body 6, a connecting body 9, and a viscoelastic material 10. The fastening body 6 connected to the brace member 5 rotates with the rotary movement of the brace member 5, and the connecting body 9 has a fixed part 8 and a retaining part 7. The fixed part 8 is fixed to a connection 4 of a building, and the retaining part 7 retains the fastening body 6 at intervals, and transfers a pulling force generated to the brace member 5 to the fixed part 8 through the medium of the fastening body 6. Then the viscoelastic material 10 is provided between the retaining part 7 of the connecting body 9 and the fastening body 6. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a seismic brace structure, and more particularly to a seismic brace structure provided in a building surface.

  A brace structure is used as a structural element that resists a horizontal force caused by, for example, seismic motion, strong wind, or the like in a building surface. In addition, in order to improve the seismic performance of existing buildings, seismic reinforcement braces are additionally attached to the wall surface as seismic reinforcement. Here, the building is a generic term for a building, a civil engineering building, a work, a frame for a machine facility, or the like. The structural frame of the building may be of any type, such as a wooden structure, a steel structure, a reinforced concrete structure, or a steel reinforced concrete structure. Further, the construction surface of the building includes not only the column beam construction surface of the wall surface, but also the construction surface composed of beams and beams on the floor surface and the roof surface. Hereinafter, the horizontal force generated by earthquake motion, strong wind, etc. is abbreviated as “horizontal force”.

  The brace structure includes an X-type brace structure which is so-called “stitching”, in which diagonal joints are attached so as to cross a building surface. Further, when there is an opening in the composition surface or when there are design restrictions, various structural forms such as a V-type brace structure and a diamond-shaped brace structure are adopted. Here, the brace structure includes all the various structural forms that resist the horizontal force caused by such earthquakes. The brace material used for these brace structures is usually longer in material length than the member width, and has a low degree of fixation to bending moment at the joints at both ends. Therefore, it becomes a pin joint member that transmits only the axial force. The brace material is used as a tensile material that bears only a tensile force without bearing a compressive force.

  As the brace material, for example, a steel bar, a cable, a square steel pipe, a shape steel such as an angle material or a channel material, or the like is used as a tensile material. Here, the steel bar refers to a solid round steel, and includes a PC steel bar. Moreover, a cable means the rope which united the steel wire more, for example, a structural strand rope and a structural spiral rope are contained.

  The brace structure generally suppresses excessive deformation that occurs in the building surface against horizontal force by adding slanting material to the building surface consisting of substantially orthogonal structural materials. It is. As will be described later, due to the horizontal force, interlayer deformation occurs in the upper and lower joints to which both ends of the brace material are attached. At this time, since both ends of the brace material are fixed to the joint portion, the brace material follows this interlayer deformation. As a result, the brace material undergoes rotational movement of the brace material itself along with the elongation due to the tensile stress. Although the rotational movement direction of the brace material is mainly within the construction surface of the building, it may be displaced to the outside of the construction surface and may be rotationally moved with twisting.

  On the other hand, a building is made to have a damping structure by arranging damping dampers in the structure. This is to absorb the energy of the horizontal force, reduce the vibration response of the entire building, and ensure the seismic safety of the building. This seismic control structure includes a seismic control brace structure in which the seismic damper is attached to a brace material in which a tensile stress is generated by a horizontal force. For these damping dampers, energy absorbing members such as viscoelastic materials, low yield point steel, lead and the like are used.

  There is a so-called joint damper as a kind of damping structure. This is because the structure of the building is deformed into a roughly rhombus shape due to horizontal force, and the angle between the column and beam at the joint changes, but this angle change is used to control the vibration control attached to the joint. Energy is absorbed by a damper.

  For example, Patent Document 1 discloses an earthquake-resistant brace device in which viscoelastic materials are alternately laminated with steel plates, and Patent Document 2 includes a joint damper that is attached to a column beam joint and incorporates a viscoelastic material. It is disclosed.

JP 2001-182359 A JP 2005-220614 A

  The vibration-damping brace structure disclosed in Patent Document 1, in which an energy absorbing member such as a viscoelastic material is sandwiched between steel plates in a sandwich shape, converts the tensile force generated in the brace material into a shear stress to form an energy absorbing member. Adopt a mechanism that allows it to act and return to tensile force. In the first place, these energy absorbing members are used as energy absorbing members due to the property of plasticizing from a low stress level. That is, these members have the property that the structural yield strength is significantly lower than that of the steel plate, but the deformation capacity is extremely high. Therefore, a complicated stress transmission mechanism is required to connect these members and the steel plate in series, and it is difficult to ensure the structural safety of the members and the joining method.

  On the other hand, the joint damper disclosed in Patent Document 2 is a dedicated energy absorbing member provided separately from the structure of the building. Therefore, a special device must be attached to each joint separately from the structural material, which is not economical because it requires installation work and construction costs.

  An object of the present application is to solve such problems, and to provide a damping brace structure that can be easily incorporated into a brace material, has high structural safety, and can efficiently absorb vibration energy.

In order to achieve the above-mentioned object, the seismic brace structure according to the present invention is provided in the construction surface of a building, and when horizontal force is applied, the relative displacement of the joints at both ends to which the brace material is connected is used. A brace structure in which the brace material undergoes axial extension and rotational movement due to tensile force, and is connected to the brace material made of the tensile material, and is connected to the brace material and rotates with the rotational movement of the brace material. Holding the body, the fixed part fixed to the joint, and the fastening body,
A holding body that transmits a tensile force generated in the brace material to the fixing portion via the fastening body, and a viscoelastic material provided in a gap between the holding body of the coupling body and the fastening body. It is characterized by that.

  Further, in the seismic damping brace structure, it is preferable that the fastening body has a curved surface in its outer shape, and the holding portion of the coupling body has a curved surface that rotatably faces the curved surface of the fastening body.

  Further, in the damping brace structure, the curved surface of the fastening body and the curved surface of the fastening body that are opposed to each other are preferably cylindrical, and are preferably, for example, steel bars. Further, in the seismic damping brace structure, the curved surface of the fastening body and the curved surface of the fastening body facing each other are preferably spherical, and for example, a steel ball is preferred.

  Further, in the seismic damping brace structure, the brace material is preferably a steel bar. For example, the brace material preferably passes through a through hole provided in the fastening body and is connected to the fastening body by a nut.

  Further, in the seismic damping brace structure, it is preferable that the fixed portion of the coupling body is fixed to an anchor bolt that penetrates the beam and is fastened to the foundation of the building.

  With the above configuration, when the rotational movement generated in the brace material is performed, the connecting body holding portion fixed to the joint by the fixing portion, and the fastening body connected to the brace material and rotating as the brace material rotates. A shift occurs between the mutually facing surfaces. The holding part of the coupling body holds the fastening body with a gap, and a viscoelastic material is provided in the gap. On the other hand, the tensile force generated in the brace material acts as a compressive force on the holding portion of the connection body fixed to the joint by the fixing portion via the fastening body. Therefore, the viscoelastic body is subjected to a compressive stress, undergoes shear deformation due to displacement, and can absorb energy such as earthquake motion due to plasticization.

  In addition, the compressive stress generated between the holding portion of the connecting body and the fastening body causes a compressive deformation in the viscoelastic body, and energy absorption such as seismic motion due to plasticization becomes possible.

  In addition, when the holding part of the coupling body and the curved surface of the fastening body that are opposite to each other have a cylindrical outer shape, the brace material follows the deviation due to this rotation when it rotates and moves within the construction surface of the building. Shearing deformation is possible, and efficient energy absorption is possible. Furthermore, when these curved surfaces have a spherical outer shape, the brace material also follows the displacement due to the rotation in these two directions even when the brace material rotates while being twisted in and out of the construction surface of the building. Shear deformation is possible, and more efficient energy absorption is possible.

  Furthermore, the compressive stress causes the viscoelastic material and the holding portion of the coupling body to be in close contact with each other and the viscoelastic material and the fastening body to be in close contact with each other, and a frictional force is generated against shear deformation of the viscoelastic body. By this frictional force, shear deformation of the viscoelastic material is surely generated, and energy absorption such as earthquake motion due to plasticization can be effectively performed.

  Moreover, this viscoelastic material should just provide a plate-shaped material in the holding | maintenance part or fastening body of a connection body as it is. For example, it can be set as the product which attached the viscoelastic material to the holding | maintenance part or fastening body of the connection body integrally by adhesion | attachment etc. Therefore, it is possible to easily incorporate the energy absorbing member into the brace material without much time and effort.

  Furthermore, as described above, the tensile force generated in the brace material acts on the viscoelastic material after being converted into a compressive stress, and no tensile stress is generated. Since the compressive yield strength of the viscoelastic material is extremely high, it is possible to ensure the structural safety of the viscoelastic body itself. In addition, a shear stress is generated in the viscoelastic material with the rotational movement of the brace material, but this shear stress is consumed as thermal energy by the shear deformation of the viscoelastic body, and it is not necessary to transmit the stress to the joint. That is, the viscoelastic body only needs to transmit compressive stress between the fastening body and the coupling body, and does not require a complicated stress transmission mechanism. Therefore, a seismic bracing with high structural safety is possible.

  As described above, according to the vibration control brace structure of the present invention, it is easy to incorporate into the brace material, the structural safety is high, and vibration energy can be absorbed reliably and efficiently.

  Embodiments according to the present invention will be described below in detail with reference to the drawings.

  1 and 2 show an outline of one embodiment of the vibration control brace structure according to the present invention. FIG. 1 is a schematic cross-sectional view of the vibration control brace structure as seen from the side, and FIG. 2 is a schematic cross-sectional view of FIG. 1 as seen from the aa direction. The vibration control brace 1 is provided in a construction surface composed of a column 2 and a beam 3, and includes a brace material 5, a fastening body 6, a connecting body 9 having a fixing part 8 and a holding part 7, and a viscoelastic body 10. .

  The brace material 5 is a structural element that resists horizontal force and is made of a tensile material. In the present embodiment, the brace material 5 is made of steel bar, and both ends are screwed and tightened with nuts 13. The brace material 5 may be, for example, a cable, a square steel pipe, a shape steel such as an angle material or a channel material, as long as it is a tensile material. Here, the steel bar refers to a solid round steel, and includes a PC steel bar. Moreover, a cable means the rope which united the steel wire more, for example, a structural strand rope and a structural spiral rope are contained.

  The fastening body 6 is attached to both ends of the brace material 5 and rotates as the brace material 5 rotates. In this embodiment, the fastening body 6 is obtained by cutting a steel bar into a predetermined length, and a through hole 12 through which the brace material 5 passes is provided in a direction orthogonal to the axis. The brace material 5 passes through the through hole 12 and is held by the nut 13. The joint between the fastening body 6 and the brace material 5 may be inserted, for example, into the screw hole cut in the fastening body 6 while rotating the brace material 5 having a screw threaded at the end thereof around the axis. . When the brace material 5 is a cable, the connection is made by a cable fixing method.

  The connecting body 9 is provided at the joint 4 where the pillar 2 and the beam 3 intersect, and connects the joint 4 and the brace material 5 via the fastening body 6. The connecting body 9 has a fixing part 8 and a holding part 7. The fixing portion 8 is fixed to the column 2 or the beam 3 of the joint 4 or both the column 2 and the beam 3. In this embodiment, the bolts are fixed to wooden pillars or beams, but a generally used method such as welding may be used. The holding part 7 holds the fastening body 6 when a tensile force is generated in the brace material 5. That is, the tensile force generated in the brace material 5 is received via the fastening body 6 and transmitted to the fixing portion 8.

  A through hole 12 is opened in the holding portion 7 and the brace material 5 penetrates. The through hole 12 is opened in a range where the brace material 5 can be rotated. In FIG. 3, the schematic sectional drawing of the other embodiment about the joining method to the fastening body 6 of the brace material 5 is shown. The brace material 5 may pass through the side surface of the holding part 7 without passing through the holding part 7 and may be connected to the fastening body 6. Further, as shown in FIG. 3, the two brace members 5 may pass through both sides of the holding part 7 without passing through the holding part 7, and may be connected to the fastening body 6. In these cases, the through hole 12 is not necessary.

  The viscoelastic body 10 is provided in the gap between the holding portion 7 and the fastening body 6. When a tensile force is generated in the brace material 5, the fastening body 6 connected to the brace material 5 is displaced in the direction of the holding portion 7. Therefore, a compressive force acts on the viscoelastic body 10 as a reaction force of the tensile force generated in the brace material 5. The viscoelastic body 10 is a polymer compound such as rubber, asphalt, or acrylic, and the material itself has damping performance. The viscoelastic body 10 generally includes all materials used as the viscoelastic material 10. The viscoelastic body 10 is processed into a sheet-like shape according to the shape of the holding portion 7 and the fastening body 6 and is attached to a predetermined position of the holding portion 7 or the fastening body 6 facing each other. This affixing may be a method of fixing with an adhesive.

  FIG. 4 shows an explanatory diagram of the behavior of the frame when the horizontal force F acts on the construction surface of the building where the brace material 5 is provided. Since the horizontal rigidity of the floor surface including the beam 3 is extremely higher than that of the column 2, shear deformation occurs in the frame. When a displacement amount B is generated in the joint 4 of the upper beam 3 with respect to the joint 4 of the lower beam 3, the brace material 5 that moves following the displacement amount B has an elongation amount of the material length. A occurs and rotational movement of the angle θ occurs. At this time, the brace material 5 has a tensile force T that gives the elongation of the material length. When the horizontal force F acts from outside the construction surface of the building, the brace material 5 undergoes rotational movement outside the construction surface.

  FIG. 5 is a schematic sectional view showing the deformation of the viscoelastic body 10 due to the rotational movement of the brace material 5. In the figure, the broken line indicates the position before deformation, and the solid line indicates the position after deformation. By the horizontal force F, a tensile force T is applied to the brace material 5 and the brace material 5 rotates about the fastening body 6 by an angle θ. The fastening body 6 rotates as the brace material 5 rotates. As described above, the viscoelastic body 10 receives the compression force C substantially equal to the tensile force T. Due to this compressive force C, a frictional force due to the compressive force C is generated between the viscoelastic body 10 and the holding portion 7 and between the viscoelastic body 10 and the fastening body 6. This frictional force acts on the viscoelastic body 10 as a shearing force. Due to this shearing force, the viscoelastic body 10 undergoes shear deformation as shown by the solid line in FIG. The viscoelastic body 10 may be fixed to the surface 14 of the holding unit 7 and the surface 15 of the coupling body 9 facing the viscoelastic body 10 with an adhesive. In that case, the shear resistance of the adhesive acts on the surface 14 and the surface 15 to cause shear deformation of the viscoelastic body 10.

  Further, the viscoelastic body 10 is compressed and deformed by the compressive force C. The viscoelastic body 10 is a sheet-like material, and the width thereof is extremely thin with respect to the length attached to the surfaces 14 and 15. Therefore, the holding part 7 and the fastening body 6 restrain the viscoelastic body 10 from protruding in the lateral direction, and the rigidity of the viscoelastic body 10 in the compression direction is increased. Therefore, the compressive deformation of the viscoelastic body 10 is extremely small compared to the shear deformation. On the other hand, the brace material 5 is a tensile material, and an initial tension is introduced. When a horizontal force is applied, the tension of the brace material 5 is released due to the compression deformation of the viscoelastic body 10, but it is within the initial tension range and does not affect the performance of the brace material 5.

  The viscoelastic body 10 exhibits damping performance by being deformed mainly by shearing force and plasticizing. That is, energy is absorbed by converting the kinetic energy of the horizontal force into heat energy. By providing this viscoelastic body 10 in each brace structure of the building, the entire building can exert a seismic control effect on horizontal force.

  In the present embodiment, the fastening body 6 is a columnar steel bar, and the surface 14 of the holding part 7 facing the viscoelastic body 10 and the surface 15 of the fastening body 6 facing the viscoelastic body 10 are both cylindrical. It is a curved surface. The two surfaces may be any curved surface as long as the connecting body 9 is rotatable with respect to the holding unit 7, or may be curved surfaces different from each other. Further, the fastening body 6 may be a sphere such as a steel ball, for example. In this case, the surface 14 of the holding part 7 facing the viscoelastic body 10 and the surface 15 of the fastening body 6 facing the viscoelastic body 10 are both spherical curved surfaces. In the case of this spherical curved surface, even when the brace material is rotationally moved while being twisted out of the construction surface of the building, the viscoelastic body 10 undergoes shear deformation due to rotational movement in that direction.

  FIG. 6 shows a schematic cross section of another embodiment of the vibration control brace structure. The holding part 7 of the coupling body 9 is cylindrical, faces the fastening body 6 that is a column, and a viscoelastic body 10 is provided in the gap. The holding part 7 has an opening in part in order to allow the nut 13 to be tightened. Moreover, the holding part 7 of the connection body 9 is spherical, the inside may oppose the fastening body 6 which is a spherical body, and the viscoelastic body 10 may be provided in the gap | interval.

  The holding part 7 of the coupling body 9 holds the fastening body 6 rotatably. In the case of building structures with different widths and heights, the mounting angles of the brace material 5 are different. According to this seismic control brace structure, the same seismic control performance can be obtained only by changing the position of the through hole 12 provided in the holding portion 7.

It is a schematic sectional drawing of one embodiment of the earthquake-resistant brace structure based on this invention. It is the schematic sectional drawing which looked at FIG. 1 from the aa direction. It is a schematic sectional drawing of the other embodiment about the joining method to the fastening body of a brace material. It is explanatory drawing about the behavior of a frame when a horizontal force acts on the frame of the building provided with the brace material. It is a schematic sectional drawing showing a deformation | transformation of the viscoelastic body by the rotational movement of a brace material. It is a schematic sectional drawing of other embodiment of an earthquake-resistant brace structure.

Explanation of symbols

  1 seismic control brace, 2 columns, 3 beams, 4 joints, 5 brace material, 6 fastening body, 7 holding part, 8 fixing part, 9 coupling body, 10 viscoelastic body, 11 bolt, 12 through hole, 13 nut, 14 A surface where the viscoelastic body and the holding portion face each other, 15 A surface where the viscoelastic body and the coupling body face each other.

Claims (9)

When the horizontal force acts on the building surface of the building, the relative displacement of the joints at both ends to which the brace material is connected causes the axial extension of the brace material and the rotational movement due to the tensile force. A brace structure where
Brace material made of tensile material,
A fastening body connected to the brace material and rotating as the brace material rotates,
A coupling body having a fixing portion fixed to the joint, and a holding portion that holds the fastening body and transmits a tensile force generated in the brace material to the fixing portion via the fastening body,
A viscoelastic material provided in a gap between the connecting body holding portion and the fastening body;
An anti-seismic brace structure characterized by comprising   2. The vibration control brace structure according to claim 1, wherein the fastening body has a curved surface in its outer shape, and the holding portion of the coupling body has a curved surface that rotatably faces the curved surface of the fastening body. Brace structure.   3. The vibration control brace structure according to claim 1, wherein the curved surface of the fastening body and the curved surface of the fastening body facing each other are cylindrical.   4. The vibration control brace structure according to claim 3, wherein the fastening body is a steel bar.   3. The vibration control brace structure according to claim 1, wherein a curved surface of the fastening body and a curved surface of the fastening body facing each other are spherical.   6. The vibration control brace structure according to claim 5, wherein the fastening body is a steel ball.   The seismic brace structure according to any one of claims 1 to 6, wherein the brace material is a steel bar.   The seismic damping brace structure according to claim 7, wherein the brace material passes through a through hole provided in the fastening body and is connected to the fastening body by a nut. 9. The vibration control brace structure according to claim 1, wherein the fixed portion of the coupling body is fixed to an anchor bolt that penetrates the beam and is fastened to the foundation of the building. Seismic brace structure.

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