Vibration control structure

Abstract

To arrange vibration control dampers so as to ensure high vibration control performance while reducing impact on rigidity of a column-beam frame.SOLUTION: A vibration control structure 1 has a steel column-beam frame 2 with vibration control dampers 13 arranged in a shear link type. The column-beam frame 2 includes a pair of neighboring columns 3, a lower beam 4, and an upper beam 5. The vibration control structure 1 includes: a pair of braces 6 whose lower ends 7d are joined to each of joints J between the pair of columns 3 and the lower beam 4 and which extend at an angle toward the center of the upper beam 5; connecting members 11 to which each of upper ends 9 of the pair of braces 6 is joined; and a vibration control damper 13 which is connected between the connecting members 11 and the upper beam 5 at an intermediate height position of the upper beam 5. The connecting members 11 and the vibration control dampers 13 are provided in pairs, sandwiching the upper beam 5 in a width direction W of the upper beam 5. Each of the pair of braces 6 branches in the width direction W at its upper end 9 and is joined to each of the pair of connecting members 11.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vibration control structure in which vibration control dampers are arranged in a shear link type inside a steel beam-column frame. [Background technology]

[0002] In architectural structures, it is common to enhance vibration control performance by arranging braces in a column-beam frame, for example, in a V-shape. For example, Patent Document 1 describes a seismic control structure that includes multiple reinforced concrete columns, multiple beams erected at intervals above and below, and diagonally extending braces placed within a structural frame formed by the columns and beams. Two braces made of seismic control dampers are placed diagonally within the structural frame. Patent Document 2 discloses a seismic control structure that includes a plurality of reinforced concrete columns erected at intervals, a plurality of reinforced concrete beams erected at intervals above and below between adjacent columns, and braces arranged within a structural frame formed by the adjacent columns and the beams facing each other above and below. In Patent Document 2, steel seismic control dampers are used as the braces. Furthermore, Patent Document 3 discloses a seismic control structure in which seismic control dampers are installed symmetrically in pairs in the form of braces in openings within the structural surface of a reinforced concrete structure.

[0003] In Patent Documents 1 to 3, the vibration dampers are configured to be included in the braces. In contrast to this, for example, in a steel beam-column frame, the vibration dampers are sometimes arranged in a shear link type. FIG. 10 is a front view of a conventional beam-column frame in which vibration dampers are arranged in a shear link configuration. In the vibration-control structure 100 shown in FIG. 10 , a pair of vibration dampers 110 are arranged in a shear-link configuration on a steel beam-column frame 102. Specifically, the beam-column frame 102 includes a pair of adjacent columns 103, a lower beam 105, and an upper beam 104. The vibration-control structure 100 also includes a pair of braces 106. The upper ends of the pair of braces 106 are joined via brackets 107 to the respective joints J between the pair of columns 103 and the upper beam 104, and the braces 106 are provided so as to extend at an angle toward the center of the lower beam 105. The lower ends of the pair of braces 106 are joined to connecting members 108 provided above the lower beam 105 at a distance from the lower beam 105. Each of the pair of vibration dampers 110 has one end joined to the connecting member 108 and the other end joined to a mounting member 109 joined to each of the joints J between the pair of columns 103 and the lower beam 105.

[0004] In the conventional configuration described above, the braces 106 and vibration dampers 110 are joined to the beam-column structure 102 via brackets 107 and mounting members 109. These brackets 107 and mounting members 109 need to have a certain level of rigidity to transmit stress between the beam-column structure 102 and the braces 106 or vibration dampers 110. As a result, the upper and lower ends of the column 103 are over-reinforced by the brackets 107 and mounting members 109. In this state, if an earthquake or other event occurs and the beam-column structure 102 attempts to deform horizontally, the range of deformation of the column 103 is limited not to its entire length HC2 but to only the height HC1, which is the total length HC2 minus the portions where the brackets 107 and mounting members 109 are provided. Therefore, in the configuration of Figure 10, the deformation performance of the column 103 may be reduced.

[0005] Furthermore, in the conventional configuration described above, the vibration damper 110 is provided inside the structural surface of the column-beam frame 102, above the lower beam 105, and the distance HC3 from the center of the upper beam 104 in the height direction to the vibration damper 110 is smaller than the story height HC4. Therefore, when an earthquake or the like occurs and the column-beam frame 102 deforms horizontally, the amount of horizontal deformation of the upper beam 104 up to the height where the vibration damper 110 is provided is smaller than the amount of inter-story deformation. For this reason, the range in which the vibration damper 110 exerts its vibration control performance is inevitably limited corresponding to this limited amount of deformation.

[0006] In order to further improve the vibration control performance of such a configuration, it is conceivable to increase the distance HC3 between the upper beam 104 and the vibration control damper 110 by providing the vibration control damper 110 at a lower position. In this way, the range HC1 in which the column 103 can deform is increased, thereby improving the deformation performance of the column 103. Furthermore, by increasing the distance HC3 between the upper beam 104 and the vibration control damper 110, the amount of deformation when an earthquake or the like occurs and the column-beam frame 102 deforms in the horizontal direction also increases, so the performance of the vibration control damper 110 is more efficiently demonstrated. In this way, it is possible to improve the vibration control performance. However, even if the vibration damper 110 is installed at a lower position, there is a limit because the beam 105 and the vibration damper 110 will interfere with each other. If the vibration damper 110 is installed at a position where it will interfere with the beam 105, it will be necessary to remove a considerable amount of the beam 105 in order to avoid this interference. In this case, there is a possibility that the rigidity of the beam-column frame will be reduced.

[0007] A vibration control structure is desired that allows vibration control dampers to be arranged so as to have high vibration control performance while reducing the impact on the rigidity of the column-beam frame. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-353258 [Patent Document 2] Japanese Patent Application Laid-Open No. 2005-036598 [Patent Document 3] Japanese Patent Application Laid-Open No. 2005-179981 Summary of the Invention [Problem to be solved by the invention]

[0009] The problem that the present invention aims to solve is to provide a vibration control structure in which vibration control dampers can be arranged so as to have high vibration control performance while reducing the impact on the rigidity of the column-beam structure. [Means for solving the problem]

[0010] In order to solve the above problems, the present invention employs the following means. Specifically, the present invention provides a vibration-control structure in which vibration-control dampers are arranged in a shear link configuration in a steel beam-column frame, the beam-column frame including a pair of adjacent columns, a lower beam, and an upper beam, a pair of braces whose lower ends are joined to each of the joints between the pair of columns and the lower beam and which extend at an angle toward the center of the upper beam, connecting members to which the upper ends of the pair of braces are joined, and the vibration-control damper is provided at an intermediate height position of the upper beam and connected between the connecting members and the upper beam, the connecting members and the vibration-control damper being provided in pairs across the width direction of the upper beam, and each of the pair of braces branches off in the width direction at its upper end and is joined to each of the pair of connecting members. According to the above-mentioned configuration, the vibration control structure includes a pair of braces, each of which has its lower end joined to the joint between a pair of columns and a lower beam and extends at an angle toward the center of the upper beam (toward the center), a joint member to which each of the upper ends of the pair of braces is joined, and a vibration control damper connected between the joint member and the column-beam frame (upper beam). In this way, the vibration control damper is arranged in a shear link type. In conventional structures, when a vibration damper is installed on the upper beam side of a beam-column frame, the damper is installed inside the beam-column frame, below the upper beam. This requires an attachment member for attaching the vibration damper at the joint between the upper beam and the column. In contrast, in the above-described structure, the vibration damper is installed at the mid-height position of the upper beam, connected between the connecting member and the upper beam. In other words, since the vibration damper is connected to the upper beam, not to the joint between the upper beam and the column, an attachment member for attaching the vibration damper is not required at the joint. This avoids excessive reinforcement of the column by the installation of an attachment member, and allows the column's deformation range to be longer than in the above-described conventional structure. This improves the column's deformation performance. In addition, the height between the lower beam to which the lower end of the brace is joined and the vibration damper to which the upper end of the brace is connected is greater than in a conventional configuration in which the vibration damper is installed below the upper beam and inside the beam-column frame. Therefore, when an earthquake or other event occurs and the beam-column frame deforms horizontally, the amount of horizontal deformation of the lower beam up to the height at which the vibration damper is installed can be greater than in a conventional configuration. Therefore, the vibration damping performance of the vibration damper can be more efficiently exerted. In this way, the vibration damping structure can be made to have higher vibration damping performance. Here, a pair of connecting members and vibration dampers are provided across the width of the upper beam, sandwiching the upper beam, and each of the pair of braces branches out in the width direction at its upper end and is joined to each of the pair of connecting members. In this way, both the vibration dampers and the connecting members to which the vibration dampers are connected and to which the upper ends of the braces are joined are arranged to avoid the upper beam in the width direction. This reduces interference between the vibration dampers and the upper beam, reducing the need to remove part of the upper beam when installing the vibration dampers at the mid-height position of the upper beam. This reduces the impact on the rigidity of the beam-column frame caused by installing the vibration dampers. In this way, it is possible to provide a vibration control structure in which vibration control dampers can be arranged so as to have high vibration control performance while reducing the impact on the rigidity of the column-beam frame.

[0011] In one aspect of the present invention, the upper beam has an upper flange, a lower flange, and a web, the lower flange has a notch in the middle of the axial direction of the upper beam, the pair of connecting members and the pair of vibration dampers are arranged at a height between the upper flange and the lower flange, on opposite sides of the web, and the upper ends of each of the pair of braces are joined to each of the pair of connecting members from below through the notch. With the above-described configuration, when installing the pair of connecting members and the pair of vibration dampers, the space enclosed by the upper flange, the lower flange, and the web on opposite sides of the web of the upper beam can be utilized, thereby achieving a rational fit. Furthermore, when joining the upper ends of the braces to the joining members provided as described above, interference may occur between the upper ends of the braces and the lower flange. In the above-described configuration, a notch is provided in the middle of the lower flange in the axial direction of the upper beam, and the upper ends of each of the pair of braces are joined to each of the pair of joining members from below through the notch. This configuration makes it possible to avoid interference between the braces and the upper beam while minimizing the loss of the upper beam.

[0012] In another aspect of the present invention, the pair of vibration dampers are oil dampers or friction dampers, the upper beam is provided with a mounting steel plate arranged along a plane perpendicular to the axial direction of the upper beam and joined to each of the upper flange, the lower flange, and the web, and each of the pair of vibration dampers is arranged extending in the axial direction and has one end joined to the mounting steel plate and the other end joined to the joining member. According to the above-described configuration, a vibration damping structure can be realized with a rational and efficient configuration. [Effects of the Invention]

[0013] According to the present invention, it is possible to provide a vibration control structure in which vibration control dampers can be arranged so as to have high vibration control performance while reducing the impact on the rigidity of the column-beam frame. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a front view of a vibration damping structure according to an embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view of part II in FIG. [Figure 3] FIG. 2 is a cross-sectional view taken along the line II-II in FIG. [Figure 4] 3 is a view of the portion of FIG. 2 viewed from an arrow A in a direction perpendicular to the upper flange of the brace. [Figure 5] 10 is a graph showing hysteresis loops at small amplitudes for the above embodiment and a conventional configuration. [Figure 6] 10 is a graph showing hysteresis loops at the time of large amplitude for the above embodiment and a conventional configuration. [Figure 7] FIG. 10 is a front view of a vibration damping structure according to a modified example of the embodiment. [Figure 8] FIG. 8 is a cross-sectional view taken along the line III-III in FIG. 7. [Figure 9] FIG. 8 is a cross-sectional view taken along the line IV-IV in FIG. 7. [Figure 10] FIG. 1 is a front view of a conventional beam-column frame in which vibration dampers are arranged in a shear link configuration. DETAILED DESCRIPTION OF THE INVENTION

[0015] This invention is a vibration control structure in which vibration dampers are installed horizontally within the depth of the upper beams in a steel beam-column frame. The vibration dampers are placed on the beam axis of the upper beam. Specifically, the vibration dampers are installed in pairs in the beam width direction, sandwiching the beam core axis in the beam width direction of the upper beam (the beam width position at the center half of the beam width, left and right positions). Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Fig. 1 is a front view of the vibration damping structure of this embodiment, Fig. 2 is a cross-sectional view of part II in Fig. 1, and Fig. 3 is a cross-sectional view of part II-II in Fig. 1. In the vibration control structure 1 of this embodiment, the column-beam frame 2 includes a pair of adjacent columns 3, a lower beam 4, and an upper beam 5. The pair of columns 3 are spaced apart in the horizontal direction V. In this embodiment, the columns 3 are formed of steel pipe columns. The columns 3 may be formed of a structure other than steel pipe columns. A lower beam 4 and an upper beam 5, which will be described later, are joined to the column 3. A diaphragm 3d is joined to the inside of the portion of the column 3 on the lower beam 4 side in the height direction H, so as to extend in a horizontal plane.

[0016] The lower beam 4 connects a pair of adjacent columns 3 in the horizontal direction V. The lower beam 4 is provided so that its axial direction coincides with the horizontal direction V, which is the direction in which the pair of adjacent columns 3 are separated. The lower beam 4 is joined to each of the pair of columns 3. In this embodiment, the lower beam 4 is an H-shaped steel. That is, the lower beam 4 includes an upper flange 4a, a lower flange 4b, and a web 4c. A reinforcing plate 4d is provided on the lower beam 4 at a position close to the column 3 so as to extend in a plane perpendicular to the horizontal direction V. The reinforcing plate 4d is joined to each of the upper flange 4a, the lower flange 4b, and the web 4c. A floor slab (not shown) is formed on the upper side of the lower beam 4, for example, to include an upper flange 4a.

[0017] The upper beam 5 connects a pair of adjacent columns 3 to each other in the horizontal direction V at a position higher than the lower beam 4. The upper beam 5 is provided parallel to the lower beam 4 so that its axial direction coincides with the horizontal direction V, which is the direction in which the pair of adjacent columns 3 are separated. The upper beam 5 is joined to each of the pair of columns 3. In this embodiment, the upper beam 5 is an H-shaped steel. That is, the upper beam 5 has an upper flange 5a, a lower flange 5b, and a web 5c. The lower flange 5b of the upper beam 5 has a notch 5d in the middle in the horizontal direction V, i.e., the axial direction of the upper beam 5. The spaces on both sides of the web 5c in the width direction W communicate with the space below the lower flange 5b via this notch 5d. A floor slab (not shown) is formed on the upper side of the upper beam 5, for example, including an upper flange 5a.

[0018] The vibration control structure 1 includes a pair of braces 6, a pair of connecting members 11, and a pair of vibration control dampers 13. Each of the pair of braces 6 includes a brace body 7, a branch member 8, and an upper end portion 9. In each of the pair of braces 6, the lower end 7d of the brace body 7 is joined to each of the joints J between the pair of columns 3 and the lower beam 4 via brackets 10 (described later). Each of the pair of braces 6, including the brace body 7 and the upper end portion 9, is arranged so that it extends at an angle toward the center (toward the center) of the upper beam 5. As a result, the pair of braces 6 are arranged so that the distance between them gradually decreases upward. Here, "near the center of the upper beam 5" refers to the section toward the center of the beam 5, excluding the beam end side of the upper beam 5 (the section from the beam end surface joined to the column to 1 / 4 of the total length of the beam). "Near the center of the upper beam 5" refers to the section toward the center of the beam, excluding the beam end side of the upper beam 5 (the section from the beam end surface joined to the column 3 to 1 / 4 of the total length of the beam). By providing a connecting member 11 near the center of this upper beam 5 and connecting the upper end of the brace 6 to the connecting member 11, the stress and deformation of the upper beam 5 can be efficiently reduced by the brace 6. In this embodiment, the brace body 7 is an H-shaped steel. That is, the brace body 7 includes an upper flange 7a, a lower flange 7b, and a web 7c. The brace body 7 is provided so that the web 7c extends within a plane formed by the horizontal direction V and the height direction H. The upper flange 7a is positioned above the lower flange 7b.

[0019] The lower end of the brace 6, i.e., the lower end 7d of the brace body 7, is joined to a bracket 10. The bracket 10 includes an upper flange 10a, a lower flange 10b, a web 10c, and a reinforcing plate 10d. The bracket 10 is provided so that the web 10c is located in the same plane as the web 7c of the brace body 7. The web 10c is positioned so that the web 7c of the brace body 7 extends diagonally downward. The web 10c is joined to the surface of the column 3 and to the upper surface of the upper flange 4a of the lower beam 4. The upper flange 10a is provided so as to extend in a horizontal plane. One end of the upper flange 10a is joined to the lower end of the upper flange 7a of the brace body 7. The other end of the upper flange 10a is joined to the surface of the column 3. The diaphragm 3d of the column 3 is provided so as to be at the same height as the upper flange 10a. The lower flange 10b is provided so as to extend in a plane perpendicular to the horizontal direction V. The upper end of the lower flange 10b is joined to the lower end of the lower flange 7b of the brace body 7. The lower end of the lower flange 10b is joined to the upper surface of the upper flange 4a of the lower beam 4. The reinforcing plate 4d of the lower beam 4 is provided so as to be in the same position as the lower flange 10b in the horizontal direction V. The reinforcing plate 10d is provided so as to be perpendicular to the web 10c, and is joined to each of the upper flange 10a, the lower flange 10b, and the web 10c.

[0020] FIG. 4 is a view of the portion of FIG. 2 seen from the direction perpendicular to the upper flange of the brace. Each of the pair of braces 6 is branched at its upper end 9 into two in the width direction W via a branching member 8. In each of the pair of braces 6, the pair of upper end portions 9 are spaced apart in the width direction W. The branched upper end portions 9 of the braces 6 are also formed of H-shaped steel, similar to the remaining portions of the braces 6, i.e., the brace bodies 7. Therefore, the upper end portions 9 include an upper flange 9a, a lower flange 9b, and a web 9c. In each of the pair of braces 6, the upper flange 9a and the lower flange 9b of the pair of upper end portions 9 are positioned in the same plane as the upper flange 7a and the lower flange 7b of the brace bodies 7. In each of the pair of braces 6, the webs 9c of each of the pair of upper end portions 9 are arranged parallel to the webs 7c of the brace bodies 7. In each of the pair of braces 6, the webs 9c of the pair of upper end portions 9 are positioned such that, when viewed from the axial direction of the braces 6, the webs 9c of the pair of upper end portions 9 are located on both sides of the web 7c of the brace bodies 7. The brace body 7 is joined from below to the branch member 8, and each of the pair of branched upper end portions 9 is joined from above. As a result, each of the pair of braces 6 is configured to branch in the width direction W at the upper end.

[0021] Each of the pair of branching members 8 includes a first mounting plate 8a, a second mounting plate 8b, a connecting plate 8c, a pair of inner branching plates 8d, a pair of side plates 8e, and a pair of outer branching plates 8f. The first mounting plate 8a is provided so as to be perpendicular to the axial direction of the brace 6. The upper flange 7a, the lower flange 7b, and the web 7c of the brace body 7 are each joined to the first mounting plate 8a from below. Similar to the first mounting plate 8a, the second mounting plate 8b is also provided so as to be perpendicular to the axial direction of the brace 6. The second mounting plate 8b is provided at a position spaced away from the first mounting plate 8a toward the upper end portions 9. The upper flange 9a, the lower flange 9b, and the web 9c of each of the pair of upper end portions 9 are joined from above to the second mounting plate 8b. The connecting plate 8c is provided at a midpoint between the upper flanges 7a, 9a and the lower flanges 7b, 9b of the brace body 7 and upper end portion 9 so as to be parallel to the upper flanges 7a, 9a and the lower flanges 7b, 9b. The connecting plate 8c connects the first mounting plate 8a and the second mounting plate 8b in the axial direction of the brace 6.

[0022] The pair of inner branch plates 8d are arranged so as to be perpendicular to the connecting plate 8c. One end of each of the pair of inner branch plates 8d is joined to the first mounting plate 8a at the position of the web 7c of the brace body 7. The other end of each of the pair of inner branch plates 8d is joined to the second mounting plate 8b at a position inside, in the width direction W, the upper flange 9a of each of the pair of upper end portions 9. As a result, the pair of inner branch plates 8d are arranged at an angle so that the distance between them gradually increases toward the upper end portions 9. The pair of outer branch plates 8f are arranged so as to be perpendicular to the connecting plate 8c. One ends of the pair of outer branch plates 8f are joined to the first mounting plate 8a at positions corresponding to both ends of the upper flange 7a of the brace body 7 in the width direction W. The other ends of the pair of outer branch plates 8f are joined to the second mounting plate 8b at positions corresponding to the webs 9c of each of the pair of upper end portions 9. As a result, the pair of outer branch plates 8f are arranged at an angle so that the distance between them gradually increases toward the upper end portions 9. Each of the pair of side plates 8e is provided at both ends of the connecting plate 8c in the width direction W. Each of the pair of side plates 8e is provided perpendicular to and joined to each of the first mounting plate 8a, the second mounting plate 8b, and the connecting plate 8c.

[0023] The pair of connecting members 11 are provided in the width direction W of the upper beam 5, sandwiching the upper beam 5 therebetween. The pair of connecting members 11 are provided at positions opposite each other with the web 5c in between, at a height between the upper flange 5a and the lower flange 5b of the upper beam 5. Each of the pair of connecting members 11 is provided at a position spaced apart from the web 5c of the upper beam 5 in the width direction W. The pair of connecting members 11 are provided so as to be movable relative to the upper beam 5 in the horizontal direction V, i.e., the axial direction of the upper beam 5.

[0024] Each of the pair of joining members 11 includes an upper flange 11a, a lower flange 11b, a web 11c, a central reinforcing plate 11d, a pair of side plates 11e, a pair of reinforcing plates 11f, and a pair of horizontal reinforcing plates 11g. In each of the pair of joining members 11, the upper flange 11a and the lower flange 11b are provided to extend in a horizontal plane. The upper flange 11a and the lower flange 11b are provided to be spaced apart in the height direction H. The web 11c is provided perpendicular to the upper flange 11a and the lower flange 11b and is joined to the upper flange 11a and the lower flange 11b. The central reinforcing plate 11d is provided so as to be perpendicular to the axial direction of the upper beam 5. The central reinforcing plate 11d is provided at the center of the connecting member 11 in the axial direction of the upper beam 5. The central reinforcing plate 11d is joined to each of the upper flange 11a, the lower flange 11b, and the web 11c. The lower end of the central reinforcing plate 11d is provided so as to protrude downward from the lower flange 11b.

[0025] In each of the pair of connecting members 11, the pair of side plates 11e are provided at both ends of the web 11c in the axial direction of the upper beam 5. Each of the pair of side plates 11e is provided perpendicular to and joined to the upper flange 11a, the lower flange 11b, and the web 11c, respectively. The pair of reinforcing plates 11f are provided parallel to the pair of side plates 11e and at positions more inward than the pair of side plates 11e in the axial direction of the upper beam 5. Each of the pair of side plates 11e is joined to each of the upper flange 11a, the lower flange 11b, and the web 11c. A pair of horizontal reinforcing plates 11g are provided between the side plate 11e and the reinforcing plate 11f so as to extend in a horizontal plane. Each of the pair of horizontal reinforcing plates 11g is provided so as to intersect with the web 11c. Each of the pair of horizontal reinforcing plates 11g is joined to each of the web 11c, the side plate 11e, and the reinforcing plate 11f.

[0026] The branched upper end portions 9 of each of the pair of braces 6 pass through notches 5d formed in the lower flanges 5b of the upper beam 5 and enter the space between the upper flanges 5a and 5b from below, and are joined to a pair of connecting members 11 positioned in the space. One of the branched upper end portions 9 of each of the pair of braces 6 is joined to each of the pair of connecting members 11. For example, the upper end portion 9 of the brace 6 on the left side, which branches toward the front in the width direction W, and the upper end portion 9 of the brace 6 on the right side, which branches toward the front in the width direction W, are joined to the connecting member 11 located on the front side of the page in FIG. 1. The upper end portion 9 of the brace 6 on the left side, which branches toward the rear in the width direction W, and the upper end portion 9 of the brace 6 on the right side, which branches toward the rear in the width direction W, are joined to the connecting member 11 located on the rear side of the page in FIG. 1. In this way, the upper ends (upper end portions 9) of each of the pair of braces 6 are joined to the pair of connecting members 11, respectively. In each of the pair of braces 6, the upper ends (upper end portions 9) are joined to the pair of connecting members 11, respectively, from below through the notches 5d.

[0027] More specifically, the upper flange 9a of each upper end portion 9 is joined to the lower surface of the lower flange 11b of the joining member 11. The upper flange 9a of the upper end portion 9 is joined to the lower flange 11b at the position of the lower end of the reinforcing plate 11f. The lower flange 9b of each upper end portion 9 is joined to the surface of the central reinforcing plate 11d of the joining member 11 at a portion that protrudes downward beyond the lower flange 11b. The web 9c of each upper end portion 9 is joined to both the lower surface of the lower flange 11b of the joining member 11 and the surface of the portion of the central reinforcing plate 11d of the joining member 11 that protrudes downwardly beyond the lower flange 11b.

[0028] The upper beam 5 is provided with a damper mounting portion 12 to which a vibration damper 13, which will be described later, is joined. A pair of damper mounting portions 12 are provided on either side of the upper beam 5 in the width direction W of the upper beam 5. The damper mounting portions 12 are provided on both sides of the width direction W, offset to one side of the axial direction, i.e., the horizontal direction V. The damper mounting portions 12 are provided on the same side of the connecting member 11 in the axial direction of the upper beam 5. In this embodiment, the damper mounting portions 12 are provided on both sides of the width direction W on the left side of the connecting member 11 in FIG. 1. The damper mounting portions 12 are provided between the column 3 and the connecting member 11.

[0029] The damper mounting portion 12 includes a mounting steel plate 12a, a column-side reinforcing plate 12b, a horizontal reinforcing plate 12c, and a pair of vertical reinforcing plates 12d. The mounting steel plate 12a is provided along a plane perpendicular to the axial direction of the upper beam 5. The mounting steel plate 12a is joined to each of the upper flange 5a, the lower flange 5b, and the web 5c. The column-side reinforcing plate 12b is provided along a plane perpendicular to the axial direction of the upper beam 5. The column-side reinforcing plate 12b is provided on the opposite side of the mounting steel plate 12a from the connecting member 11, i.e., on the column 3 side, at a position spaced apart from the mounting steel plate 12a. The column-side reinforcing plate 12b is joined to each of the upper flange 5a, the lower flange 5b, and the web 5c. As shown in Fig. 3, the mounting steel plate 12a and the column-side reinforcing plate 12b are formed so that the width of the middle part in the height direction is wider than the width at the upper end and the lower end. The mounting steel plate 12a and the column-side reinforcing plate 12b are formed so that when a vibration damper 13, which will be described later, is attached to the mounting steel plate 12a, the vibration damper 13 is included in the mounting steel plate 12a and the column-side reinforcing plate 12b when viewed from the axial direction of the upper beam 5 as shown in Fig. 3.

[0030] The horizontal reinforcing plate 12c is provided between the mounting steel plate 12a and the column-side reinforcing plate 12b so as to extend in a horizontal plane. The horizontal reinforcing plate 12c is provided at the center position in the height direction H of the upper beam 5. The horizontal reinforcing plate 12c is joined to each of the web 5c of the upper beam 5, the mounting steel plate 12a, and the column-side reinforcing plate 12b. The pair of vertical reinforcing plates 12d are provided on both sides of the web 5c in the width direction W of the upper beam 5 so as to extend in a vertical plane perpendicular to each of the mounting steel plate 12a, the column-side reinforcing plate 12b, and the horizontal reinforcing plate 12c, and are joined to each of the mounting steel plate 12a, the column-side reinforcing plate 12b, and the horizontal reinforcing plate 12c. Each of the pair of vertical reinforcing plates 12d is provided so as to intersect with the horizontal reinforcing plate 12c.

[0031] A pair of vibration dampers 13 are provided in the width direction W of the upper beam 5, sandwiching the web 5c of the upper beam 5. Each of the pair of vibration dampers 13 is provided at an intermediate height position of the upper beam 5, more specifically, at a height between the upper flange 5a and the lower flange 5b of the upper beam 5. Each of the pair of vibration dampers 13 is provided offset to one side of the axial direction, i.e., the horizontal direction V, on both sides of the width direction W. The vibration dampers 13 are provided on the same side of the connecting member 11 in the axial direction of the upper beam 5. In this embodiment, the vibration dampers 13 are provided on the left side of the connecting member 11 in FIG. 1 on both sides of the width direction W. The vibration dampers 13 are provided between the connecting member 11 and the damper mounting portion 12.

[0032] In this embodiment, each of the pair of vibration dampers 13 is an oil damper. The vibration dampers 13 may be friction dampers. A pair of vibration dampers 13 are provided between the connecting member 11 and the upper beam 5, more specifically, between the connecting member 11 and the damper mounting portion 12 of the upper beam 5, so as to connect them. Each of the pair of vibration dampers 13 is provided so as to extend in the axial direction of the upper beam 5, i.e., the horizontal direction V. One end 13a of each vibration damper 13 is joined to the mounting steel plate 12a of the damper mounting portion 12. In particular, the one end 13a of the vibration damper 13 is joined to a position of the mounting steel plate 12a corresponding to the intersection of the horizontal reinforcing plate 12c and the vertical reinforcing plate 12d. The other end 13b of each vibration damper 13 is joined to the surface of the side plate 11e of the connecting member 11 located on the damper mounting portion 12 side. In this way, a vibration control structure 1 is realized in which vibration control dampers 13 are arranged in a shear link type on a steel beam-column frame 2.

[0033] In the above-described configuration, a case will be considered in which a horizontal force is applied due to an earthquake or the like, causing the upper beam 5 to displace relative to the lower beam 4 in the horizontal direction V. The brace 6 and the connecting member 11 to which the brace 6 is joined are joined to the joint J between the lower beam 4 and the column 3 via the bracket 10, so the brace 6 and the connecting member 11 are displaced together with the lower beam 4. Therefore, when the upper beam 5 displaces horizontally relative to the lower beam 4, the upper beam 5 and the connecting member 11 are displaced relative to each other in the horizontal direction V. This relative displacement is absorbed and damped by the vibration damper 13, one end 13a of which is joined to the damper mounting portion 12 of the upper beam 5 and the other end 13b of which is joined to the connecting member 11.

[0034] At this time, stress from the vibration damper 13 acts on the damper mounting portion 12 at one end 13a of the vibration damper 13. Here, a horizontal reinforcing plate 12c and a vertical reinforcing plate 12d are provided and joined so as to intersect on the opposite side of the mounting steel plate 12a of the damper mounting portion 12, to which one end 13a of the vibration damper 13 is joined. Therefore, the portion of the damper mounting portion 12 to which one end 13a is joined has sufficient rigidity. For this reason, stress acting from the vibration damper 13 to the damper mounting portion 12 is sufficiently transmitted to the upper beam 5 via the damper mounting portion 12.

[0035] Furthermore, at the other end 13b of the vibration damper 13, stress from the vibration damper 13 is transmitted to the connecting member 11. Here, on the side plate 11e of the connecting member 11 to which the other end 13b of the vibration damper 13 is joined, a web 11c and a horizontal reinforcing plate 11g are provided and joined so that they intersect on the opposite side from the vibration damper 13. Therefore, the portion of the connecting member 11 to which the other end 13b is joined has sufficient rigidity. For this reason, stress acting from the vibration damper 13 to the connecting member 11 is transmitted sufficiently to the brace 6 via the connecting member 11. The stress transmitted from the connecting member 11 to the brace 6 is then transmitted to the bracket 10. The upper flange 10a of the bracket 10 is continuous with the diaphragm 3d of the column 3, and the lower flange 10b is continuous with the reinforcing plate 4d of the lower beam 4. Therefore, the stress acting on the brace 6 from the connecting member 11 is smoothly transmitted to the column-beam frame 2.

[0036] The vibration control structure 1 as described above is a vibration control structure 1 in which vibration control dampers 13 are arranged in a shear link type on a steel column-beam frame 2, and the column-beam frame 2 comprises a pair of adjacent columns 3, a lower beam 4, and an upper beam 5, and the pair of braces 6 have their lower ends 7d joined to each of the joints J between the pair of columns 3 and the lower beams 4, and are arranged so as to extend at an angle toward the center of the upper beam 5 (toward the center), connecting members 11 to which each of the upper ends (upper end portions 9) of the pair of braces 6 are joined, and the vibration control damper 13 is arranged at an intermediate height position of the upper beam 5 and connected between the connecting members 11 and the upper beam 5, and the connecting members 11 and the vibration control damper 13 are arranged in pairs on either side of the upper beam 5 in the width direction W of the upper beam 5, and each of the pair of braces 6 branches in the width direction W at its upper end (upper end portion 9) and is joined to each of the pair of connecting members 11. According to the above-described configuration, the vibration control structure 1 includes a pair of braces 6, each having its lower end 7d joined to each of the joints J between a pair of columns 3 and lower beams 4, and extending at an angle toward the center (toward the center) of the upper beam 5, connecting members 11 to which each of the upper ends (upper end portions 9) of the pair of braces 6 is joined, and a vibration control damper 13 provided and connected between the connecting members 11 and the beam-column frame 2 (upper beam 5). In this way, the vibration control damper 13 is arranged in a shear link type. When a vibration damper 13 is provided on the upper beam 5 side of such a beam-column frame 2, in a conventional configuration, the vibration damper 13 is provided inside the beam-column frame 2, below the upper beam 5. This requires providing a mounting member V1 (see FIG. 1 ) for mounting the vibration damper 13 at the joint J between the upper beam 5 and the column 3 at the height where the vibration damper 13 is to be mounted. In contrast, in the above configuration, the vibration damper 13 is provided at the mid-height position of the upper beam 5, connected between the connecting member 11 and the upper beam 5. That is, since the vibration damper 13 is connected to the upper beam 5 rather than to the joint J between the upper beam 5 and the column 3, there is no need to provide a mounting member V1 for mounting the vibration damper 13 at the joint J. This avoids excessive reinforcement of the column 3 by providing the mounting member V1, and allows the deformation range HP2 of the column 3 to be longer than the deformation range HP1 of the column 3 in the above-described conventional configuration. This improves the deformation performance of the column 3. Furthermore, the height HP4 between the lower beam 4 to which the lower end 7d of the brace 6 is joined and the vibration damper 13 to which the upper end (upper end 9) of the brace 6 is connected is greater than the height HP3 in a conventional configuration in which the vibration damper 13 is provided inside the column-beam frame 2, below the upper beam 5. Therefore, when an earthquake or the like occurs and the column-beam frame 2 deforms in the horizontal direction V, the amount of deformation in the horizontal direction V of the lower beam 4 up to the height at which the vibration damper 13 is provided can be greater than in a conventional configuration. Therefore, the vibration damping performance of the vibration damper 13 can be more efficiently exhibited. In this way, the vibration damping structure 1 can be made to have higher vibration damping performance. Here, the connecting member 11 and the vibration damper 13 are provided in pairs, sandwiching the upper beam 5 in the width direction W of the upper beam 5, and each of the pair of braces 6 branches at its upper end (upper end 9) in the width direction W and is joined to each of the pair of connecting members 11. In this way, both the vibration damper 13 and the connecting member 11 to which the vibration damper 13 is connected and to which the upper end (upper end 9) of the brace 6 is joined are provided so as to avoid the upper beam 5 in the width direction W. This reduces interference between the vibration damper 13 and the upper beam 5, and reduces the need to remove part of the upper beam 5 when providing the vibration damper 13 at an intermediate height position of the upper beam 5. This reduces the impact on the rigidity of the beam-column frame 2 caused by providing the vibration damper 13. In addition, because the vibration control dampers 13 do not protrude above the upper beams 5, the vibration control structure 1 does not appear in the living space, ensuring freedom of the living space. Furthermore, because the vibration control dampers 13 are arranged within the beam depth of the upper beams 5, inter-story deformation becomes shear deformation of the vibration control dampers 13, resulting in high vibration control efficiency and reduced response during earthquakes. In this way, it is possible to provide a vibration control structure 1 in which the vibration control dampers 13 can be arranged so as to have high vibration control performance while reducing the effect on the rigidity of the column-beam frame 2.

[0037] The upper beam 5 also has an upper flange 5a, a lower flange 5b, and a web 5c, and the lower flange 5b has a notch 5d in the middle in the axial direction (horizontal direction V) of the upper beam 5, and a pair of connecting members 11 and a pair of vibration dampers 13 are arranged at a height between the upper flange 5a and the lower flange 5b, on opposite sides of the web 5c, and the upper ends (upper end portions 9) of each of the pair of braces 6 are joined to each of the pair of connecting members 11 from below through the notch 5d. According to the above-described configuration, when installing the pair of connecting members 11 and the pair of vibration dampers 13, it is possible to utilize the space surrounded by the upper flange 5a, the lower flange 5b, and the web 5c on opposite sides of the web 5c of the upper beam 5. Therefore, the fit can be made rational. Furthermore, when joining the upper end (upper end 9) of the brace 6 to the joining member 11 provided as described above, there is a possibility that interference may occur between the upper end (upper end 9) of the brace 6 and the lower flange 5b. Here, in the configuration described above, a notch 5d is provided in the middle portion of the lower flange 5b in the axial direction of the upper beam 5, and the upper end (upper end 9) of each of the pair of braces 6 is joined from below to each of the pair of joining members 11 through the notch 5d. In this way, interference between the brace 6 and the upper beam 5 can be avoided while minimizing the loss portion of the upper beam 5.

[0038] In principle, it is also possible to invert the configuration shown in Figure 1 and place the connecting member 11 and vibration damper 13 at a height between the upper flange 4a and lower flange 4b ​​of the lower beam 4, form a notch in the upper flange 4a of the lower beam 4, and have the brace 6, whose upper end is joined to the joint J between the column 3 and the upper beam 5, pass through the notch from above and join to the connecting member 11 placed at the height of the lower beam 4. However, because a floor slab (not shown) is formed above the upper flange 4a, the brace 6 must also penetrate the floor slab when inserting it through the notch in the lower beam 4. This configuration is not practical for several reasons, including the need to create insertion holes in the floor slab, which reduces the rigidity of the floor slab, and the difficulty of ensuring sufficient clearance between the brace 6 and each component, including the floor slab. For these reasons, in this embodiment, the brace 6 extends upward from the underside of the upper beam 5 across the lower flange 5b, as shown in FIG. 1.

[0039] In addition, the pair of vibration dampers 13 are oil dampers or friction dampers, and the upper beam 5 is provided with mounting steel plates 12a arranged along a plane perpendicular to the axial direction (horizontal direction V) of the upper beam 5 and joined to each of the upper flange 5a, lower flange 5b, and web 5c, and each of the pair of vibration dampers 13 is arranged extending in the axial direction (horizontal direction V), with one end 13a joined to the mounting steel plate 12a and the other end 13b joined to the joining member 11, respectively. According to the above-described configuration, the vibration control structure 1 can be realized with a rational and efficient configuration.

[0040] The pair of vibration dampers 13 are provided on the same side of the connecting member 11 in the axial direction of the upper beam 5 (horizontal direction V). According to the above-described configuration, the pair of vibration dampers 13 are provided on the same side of the connecting member 11 in the axial direction (horizontal direction V) of the upper beam 5, and therefore the damper mounting portions 12 are also provided on the same side of the connecting member 11. This allows the damper mounting portions 12 to be configured symmetrically across the web 5c. Therefore, the damper mounting portions 12 can be concentrated in one location on the upper beam 5, resulting in a simple configuration.

[0041] (Analysis results) Next, the analysis results for the vibration-damping structure 1 of the above embodiment and a conventional vibration-damping structure 100 as shown in FIG. 10 will be described. As an analysis, a comparison of restoring force loops was carried out when forced displacement was applied to the dashpot. The analysis conditions were maximum damping force of 2000kN, relief damping force of 1600kN, relief speed of 3.2kine, and maximum speed of 30kine. Specifically, the displacement is a sine wave with a period of 4 seconds, and in the vibration-damping structure 1 of the above embodiment, the dashpot displacement is set to 100% of the forced displacement, while in the conventional vibration-damping structure 1, the dashpot displacement is set to 80% of the forced displacement. The dashpot is designed to relieve depending on the speed, with an initial damping coefficient of 50 kNs / mm, 3.39 kNs / mm after relief, a speed during relief of 32 mm / s, and a load of 1600 kN. These values ​​correspond to those of a typical vibration-damping damper.

[0042] Fig. 5 is a graph showing the hysteresis loops at small amplitudes for the above embodiment and a conventional configuration. Fig. 6 is a graph showing the hysteresis loops at large amplitudes for the above embodiment and a conventional configuration. In both of these figures, the hysteresis loop for the conventional configuration is shown by line L1, and the hysteresis loop for the above embodiment is shown by line L2. The area of ​​the loop is the energy absorption efficiency of the damper. Compared to the conventional configuration, the area of ​​the configuration of the above embodiment increases by 56% at small amplitudes and by 31% at large amplitudes, demonstrating the effectiveness of the above embodiment.

[0043] (Modification of the embodiment) The vibration damping structure of the present invention is not limited to the above-described embodiment explained with reference to the drawings, and various other modifications are possible within the technical scope of the structure. Fig. 7 is a front view of a vibration damping structure according to a modified example of the embodiment, Fig. 8 is a cross-sectional view taken along line III-III in Fig. 7, and Fig. 9 is a cross-sectional view taken along line IV-IV in Fig. 7. The vibration-damping structure 21 of this modified example differs from the vibration-damping structure 1 of the above embodiment in the structures of the brace 26, bracket 30, connecting member 31, and vibration damper 33. Only these different parts will be described below.

[0044] The vibration control structure 21 includes a pair of braces 26 , a pair of connecting members 31 , and a pair of vibration control dampers 33 . Each of the pair of braces 26 includes a brace body 27 and an upper end portion 29. In each of the pair of braces 26, a lower end 27d of the brace body 27, which serves as the lower end of the brace 26, is joined via a bracket 30 to each of the joints J between the pair of columns 3 and the lower beam 4. The brace body 27 is an H-shaped steel. That is, the brace body 27 has a pair of flanges 27a and a web 27c. The brace body 27 is provided so that each of the pair of flanges 27a extends within a plane formed by the horizontal direction V and the height direction H. The lower end of the brace 26, i.e., the lower end 27d of the brace body 27, is joined to a bracket 30. The bracket 30 is made of a steel plate, and a pair of brackets 30 are provided corresponding to the flanges 27a of the brace body 27. The brackets 30 are provided to extend within a vertical plane formed by the horizontal direction V and the height direction H. The brackets 30 are joined to the surface of the column 3 and to the upper surface of the upper flange 4a of the lower beam 4.

[0045] Each of the pair of braces 26 is branched into two at an upper end portion 29 in the width direction W. In each of the pair of braces 26, the pair of upper end portions 29 are provided spaced apart in the width direction W. Each of the pair of upper end portions 29 of the brace 26 in this modified example includes a flange 29a and a web 29c. The flange 29a is formed so that the flange 27a of the brace body 27 extends upward. The web 29c is formed so that only the outer portion of the web 27c of the brace body 27 in the width direction W extends upward. The outer edge of the web 29c in the width direction W is joined to the flange 29a.

[0046] The pair of connecting members 31 are provided in the width direction W of the upper beam 5, sandwiching the upper beam 5 therebetween. The pair of connecting members 31 are provided at positions opposite each other with the web 5c in between, at a height between the upper flange 5a and the lower flange 5b of the upper beam 5. Each of the pair of connecting members 31 is provided at a position spaced apart from the web 5c of the upper beam 5 in the width direction W. The pair of connecting members 31 are provided so as to be movable relative to the upper beam 5 in the horizontal direction V, i.e., the axial direction of the upper beam 5. In this modification, each of the pair of connecting members 31 is a single steel plate provided parallel to the web 5c of the upper beam 5.

[0047] The branched upper end portions 29 of each of the pair of braces 26 pass through notches 5d formed in the lower flange 5b of the upper beam 5 and enter the space between the upper flange 5a and the lower flange 5b from below, and are joined to each of a pair of connecting members 31 positioned in that space. One of the branched upper end portions 29 of each of the pair of braces 26 is joined to each of the pair of connecting members 31. For example, the upper end portion 29 branched toward the front in the width direction W of the brace 26 located on the left side and the upper end portion 29 branched toward the front in the width direction W of the brace 26 located on the right side are joined to the connecting member 31 located on the front side of the page in FIG. 7 . In addition, the upper end 29 of the brace 26 located on the left side, which branches off toward the rear in the width direction W, and the upper end 29 of the brace 26 located on the right side, which branches off toward the rear in the width direction W, are each joined to the joining member 31 located at the rear of the paper in Figure 7. In this way, the upper ends (upper end portions 29) of the pair of braces 26 are joined to the pair of connecting members 31, respectively. The upper ends (upper end portions 29) of the pair of braces 26 are joined to the pair of connecting members 31, respectively, from below through the notches 5d. Each of the pair of braces 26 has a flange 29a at its upper end 29 provided along the connecting member 31 and joined to the connecting member 31 by a high-strength bolt 31a.

[0048] A pair of vibration dampers 33 are provided in the width direction W of the upper beam 5, sandwiching the web 5c of the upper beam 5. Each of the pair of vibration dampers 33 is provided at an intermediate height position of the upper beam 5, more specifically, at a height between the upper flange 5a and the lower flange 5b of the upper beam 5. Each of the pair of vibration dampers 33 is provided on both sides of the width direction W, offset to one side of the axial direction, i.e., the horizontal direction V. The vibration dampers 33 are provided on the same side of the connecting member 31 in the axial direction of the upper beam 5. The pair of vibration dampers 33 are provided between the connecting member 31 and the upper beam 5, more specifically between the connecting member 31 and the damper mounting portion 12 of the upper beam 5, so as to connect them. Each of the pair of vibration dampers 33 is provided so as to extend in the axial direction of the upper beam 5, i.e., in the horizontal direction V. One end 33a of each vibration damper 33 is pin-connected to a connecting steel plate 33d joined to the mounting steel plate 12a of the damper mounting portion 12. The other end 33b of each vibration damper 33 is pin-connected to the connecting member 31. In this way, a vibration control structure 21 is realized in which the vibration control dampers 33 are arranged in a shear link type on the steel beam-column frame 2.

[0049] In addition to this, it is possible to select and discard the configurations given in the above embodiment and modified examples, or to change them to other configurations as appropriate. [Explanation of symbols]

[0050] 1, 21 Vibration control structure 8 Branching member 2 Column beam frame 9, 29 Upper end (upper end) 3 Columns 11, 31 Joint members 4 Lower beam 12 Damper mounting part 5 Upper beam 12a Mounting steel plate 5a Upper flange 13, 33 Vibration damper 5b Lower flange 13a, 33a One end 5c Web 13b, 33b other end 5d Notch W Width direction 6, 26 Brace H Height direction 7, 27 Brace body V Horizontal direction (axial direction) 7d, 27d bottom edge

Claims

1. A vibration control structure in which vibration control dampers are arranged in a shear link type on a steel column-beam frame, The column-beam frame includes a pair of adjacent columns, a lower beam, and an upper beam, A pair of braces, each having a lower end joined to each of the joints between the pair of columns and the lower beam, and extending obliquely toward the center of the upper beam; a connecting member to which each of the upper ends of the pair of braces is connected; The vibration damper is provided at an intermediate height position of the upper beam and is connected between the connecting member and the upper beam; Equipped with The connecting member and the vibration damper are provided as a pair on either side of the upper beam in the width direction of the upper beam, Each of the pair of braces is branched at the upper end in the width direction and joined to each of the pair of joining members. A vibration-damping structure characterized by:

2. the upper beam includes an upper flange, a lower flange, and a web, and the lower flange includes a notch in a middle portion in an axial direction of the upper beam; the pair of connecting members and the pair of vibration dampers are provided at positions opposite to each other across the web at a height between the upper flange and the lower flange, In each of the pair of braces, the upper ends are joined to the pair of joining members from below through the notches.

2. The vibration damping structure according to claim 1.

3. the pair of vibration dampers are oil dampers or friction dampers, the upper beam includes a mounting steel plate provided along a plane perpendicular to the axial direction of the upper beam and joined to each of the upper flange, the lower flange, and the web; Each of the pair of vibration dampers is provided to extend in the axial direction, and one end is joined to the mounting steel plate and the other end is joined to the joining member.

3. The vibration damping structure according to claim 2.

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