Damper attachment structure

Abstract

To provide a damper attachment structure for attaching damper in a horizontal posture arranged in a base isolation layer capable of exerting relatively high rigidity to exert vibration damping effect through the damper at a lower end part of a strut member even when a top part of the struct member is not allowed to be connected with a large beam having a beam core parallel to a shaft core of the damper when being provided with a steel structural strut members, a top part of which is connected to an upper structural body to extend downward and on which a lower end part is rotatably connected around a vertical shaft.SOLUTION: An upper structural body 2 is provided with a connection part through steel beam 21 having a horizontal core passing through a connection part of a top part 30a of a strut member 30, and an oblique posture reinforce rigid member 41, one end 41a of which is connected to a lower end part 30b of the strut member 30 and the other end 41b of which is connected on the connection part through steel beam 21.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a damper mounting structure for mounting a damper in a seismic isolation layer between an upper structure and a lower structure, wherein one end is rotatably connected to the upper structure around a vertical axis and the other end is rotatably connected to the lower structure around a vertical axis in a horizontal posture.

Background Art

[0002] In a damper mounting structure for mounting a damper in a horizontal posture in a seismic isolation layer between an upper structure and a lower structure, there is known one including a steel frame bundle member having a top portion joined to the upper structure and extending downward, and one end of the damper being rotatably connected to the lower end portion around a vertical axis (see, for example, Patent Document 1). In such a damper mounting structure, a relatively high rigidity is required at the lower end portion of the bundle member to which the damper is connected and a relatively large horizontal load is applied from the damper in order to favorably exhibit the vibration damping effect by the damper. Therefore, in the damper mounting structure described in Patent Document 1, in the upper structure, the top portion of the bundle member is rigidly joined to a large beam having a beam axis parallel to the axis of the damper, and further, a bundle member having a relatively large cross-sectional area with respect to the vertical length is adopted in order to increase the bending rigidity of the bundle member itself.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, for example, when a large number of dampers are arranged in a seismic isolation layer, etc., the top of the bundled member cannot be joined to a large beam having a beam axis parallel to the axis of the damper. For example, there may be a need to join the top of the bundled member to a small beam, or to a large beam having a beam axis not parallel to the axis of the damper. And in such a case, the rigidity against the horizontal load transmitted from the damper at the joint of the top of the bundled member decreases, and accordingly, the rigidity at the lower end of the bundled member also decreases. Further, when the top of the bundled member is joined to a small beam with a small beam formation, the required steel material increases with the increase in the length of the bundled member, and the rigidity of the lower end of the bundled member further decreases.

[0005] In view of this actual situation, the main problem of the present invention is that in a damper mounting structure for mounting a horizontally oriented damper arranged in a seismic isolation layer between an upper structure and a lower structure, when a steel-frame bundled member having a top joined to the upper structure and extending downward, and one end of the damper being rotatably connected around a vertical axis at the lower end thereof, even when the top of the bundled member cannot be joined to a large beam having a beam axis parallel to the axis of the damper, at the lower end of the bundled member, in order to favorably exhibit the vibration damping effect by the damper, to provide a technique for exhibiting relatively high rigidity.

Means for Solving the Problems

[0006] A first characteristic configuration of the present invention is a damper mounting structure for mounting a horizontally oriented damper arranged in a seismic isolation layer between an upper structure and a lower structure, one end of which is rotatably connected around a vertical axis to the upper structure and the other end of which is rotatably connected around a vertical axis to the lower structure, comprising a steel-frame bundled member having a top joined to the upper structure and extending downward, and one end of the damper being rotatably connected around a vertical axis at the lower end thereof, in the upper structure, a joint-through steel beam having a horizontal beam axis passing through the joint of the top of the bundled member is provided, and at the lower end of the bundled member, a diagonal stiffening member having one end joined thereto and the other end joined to the joint-through steel beam is provided.

[0007] According to this configuration, even when a relatively large horizontal load is applied to the lower end of a bundled member made of steel and having a top joined to the upper structure and extending downward, with one end of a damper rotatably connected to the lower end about a vertical axis, the horizontal displacement of the lower end of the bundled member can be suppressed by a supplementary stiffening member joined to the lower end. That is, at the joint of the supplementary stiffening member in the steel beam along the joint, since the steel beam along the joint has a horizontal beam axis passing through the joint at the top of the bundled member, the rigidity against a horizontal load parallel to the beam axis becomes high. Therefore, by joining this supplementary stiffening member to the lower end of the bundled member in a posture along the beam axis of the steel beam along the joint, the rigidity parallel to the beam axis at the lower end of the bundled member can be improved. Therefore, according to the present invention, in a damper mounting structure for mounting a horizontally oriented damper disposed in a seismic isolation layer between an upper structure and a lower structure, when providing a bundled member made of steel and having a top joined to the upper structure and extending downward, with one end of a damper rotatably connected to the lower end about a vertical axis, a technique can be provided that exhibits relatively high rigidity at the lower end of the bundled member in order to favorably exert the vibration damping effect by the damper.

[0008] A second characteristic configuration of the present invention is that the supplementary stiffening member is composed of an H-shaped steel with both flanges in a horizontal posture along a vertical plane, and a connection pin insertion / removal hole for inserting and removing a vertically oriented connection pin at the connection portion of the damper with respect to the lower end of the bundled member is formed on the web of the supplementary stiffening member on the lower end side of the bundled member.

[0009] According to this configuration, even when the joint of the supplementary stiffening member is brought as close as possible to the connection portion of the damper in order to increase the rigidity of the connection portion where the damper is connected at the lower end of the bundled member, the connection pin such as a clevis pin in a vertical posture at the connection portion of the damper can be easily inserted and removed from above through the connection pin insertion / removal hole formed in the web of the horizontally oriented H-shaped steel constituting the support.

[0010] The third characteristic configuration of the present invention lies in that the joint at the top of the bundle member in the upper structure is a part where there is no large beam having a beam axis parallel to the axis of the damper.

[0011] According to this configuration, in the upper structure, even when the joint at the top of the bundle member is a part with relatively low rigidity against a horizontal load parallel to the axis of the damper because there is no large beam having a beam axis parallel to the axis of the damper, by providing a supplementary rigid member with one end joined to the lower end of the bundle member and the other end joined to the upper structure, relatively high rigidity can be exhibited at the lower end of the bundle member.

[0012] The fourth characteristic configuration of the present invention is that in the upper structure, as a steel girder passing through the joint, a first steel girder having a horizontal beam axis passing through the joint at the top of the bundle member and a second steel girder having a horizontal beam axis orthogonal to the beam axis of the first steel girder at the joint at the top of the bundle member are provided. The supplementary rigid member with one end joined to the lower end of one of the bundle members includes a first supplementary rigid member with the other end joined to the first steel girder and a second supplementary rigid member with the other end joined to the second steel girder.

[0013] According to this configuration, in the upper structure, when there are a first steel girder and a second steel girder each having a beam axis orthogonal to each other at the joint at the top of the bundle member, by providing the first supplementary rigid member and the second supplementary rigid member joined to the first steel girder and the second steel girder respectively, high rigidity can be exhibited against any horizontal load in any horizontal direction at the lower end of the bundle member. That is, at the joint of the first supplementary stiffening member in the first steel frame beam, the rigidity against the horizontal load parallel to the beam axis of the first steel frame beam becomes high. Therefore, by joining this first supplementary stiffening member to the lower end of the bundled member, the rigidity against the horizontal load parallel to the beam axis of the first supplementary stiffening member at the lower end of the bundled member can be improved. On the other hand, at the joint of the second supplementary stiffening member in the second steel frame beam, the rigidity against the horizontal load parallel to the beam axis of the second steel frame beam orthogonal to the beam axis of the first supplementary stiffening member becomes high. Therefore, by joining this second supplementary stiffening member to the lower end of the bundled member, the rigidity against the horizontal load parallel to the beam axis of the second supplementary stiffening member at the lower end of the bundled member can be improved. As a result, high rigidity is exhibited along the respective beam axes of the first steel frame beam and the second steel frame beam orthogonal to each other at the lower end of the bundled member.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0015] Embodiments of the present invention will be described with reference to the drawings. Fig. 1 shows a plan view of the state of the seismic isolation layer 3 in which the dampers 11 are installed by adopting the damper mounting structures 1A and 1B of the present embodiment. A plurality of seismic isolation bearings 4 are arranged in a seismic isolation layer 3 between a superstructure 2 to be isolated and a substructure 5 such as a foundation, and the superstructure 2 is supported by the substructure 5 via these plurality of seismic isolation bearings 4. Further, a plurality of dampers 11 for damping the horizontal sway of the superstructure 2 generated during an earthquake or the like are arranged in the seismic isolation layer 3. That is, although details will be described later, one end 11a of the damper 11 is rotatably connected to the superstructure 2 around a vertical axis, and the other end 11b is rotatably connected to the substructure 5 around a vertical axis, and is installed in a horizontal posture.

[0016] Specifically, as shown in FIGS. 2 and 4, one end 11a of the damper 11 is rotatably connected to the lower end 30b of a bundled member 30 made of steel and having a lower end 30b joined to the superstructure 2 and extending downward, by a connecting portion 15 configured as a clevis fastener, around the vertical axis of a vertically oriented connecting pin 15A of the connecting portion 15. On the other hand, the other end 11b of the damper 11 is rotatably connected to a pedestal portion 6 made of reinforced concrete protruding upward from the substructure 5, by a connecting portion 18 configured as a clevis fastener, around the vertical axis of a vertically oriented connecting pin 18A of the connecting portion 18. With this configuration, one end 11a and the other end 11b of the damper 11 are located at the same height, and the damper 11 is maintained in a horizontal posture. Then, following the horizontal sway of the superstructure 2 with respect to the substructure 5, the damper 11 expands and contracts with the rotation of the ends 11a and 11b with respect to the connecting portions 15 and 18, and the horizontal sway of the superstructure 2 is damped.

[0017] In the lowermost layer of the superstructure 2 facing the seismic isolation layer 3, there are a large beam 2A spanned between a pair of columns, a small beam 2B spanned between a pair of large beams 2A, and a small beam 2C (hereinafter referred to as a grandchild beam 2C in the following description) spanned between a pair of small beams 2B. The slab 25 is supported by these beams 2A, 2B, and 2C. And the top 30a of the bundling member 30 of the damper mounting structures 1A and 1B is joined to the main beam 2A or the secondary beam 2B. In FIG. 1, the horizontal direction is referred to as the X direction, and the vertical direction is referred to as the Y direction. And in the present embodiment, as shown in FIG. 1, a plurality of secondary beams 2B having beam cores parallel to the X direction are installed between a pair of main beams 2A having beam cores parallel to the Y direction, and further, in some regions, a plurality of grandchild beams 2C having beam cores parallel to the Y direction are installed between a pair of secondary beams 2B having beam cores parallel to the X direction.

[0018] In the seismic isolation layer 3 shown in FIG. 1, there are a damper mounting structure 1A of the first embodiment (see FIGS. 2 and 3) in which the top 30a of the bundling member 30 is joined to the main beam 2A, and a damper mounting structure 1B of the second embodiment (see FIGS. 3 and 4) in which the top 30a of the bundling member 30 is joined to the secondary beam 2B. Hereinafter, the detailed configurations of the damper mounting structures 1A and 1B of the first embodiment and the second embodiment will be described.

[0019] 〔First Embodiment〕 The detailed configuration of the damper mounting structure 1A of the first embodiment will be described with reference to FIGS. 2, 3, and 6. As shown in FIGS. 2 and 3, in the damper mounting structure 1A of the present embodiment, the top 30a of the bundling member 30 is bolted to the main beam 2A having a beam core parallel to the Y direction via a bracket 31 made of a gusset plate. Also, the joint portion of the top 30a of the bundling member 30 on the main beam 2A is the joint location of the secondary beam 2B having a beam core parallel to the X direction with respect to the main beam 2A. That is, in the superstructure 2, joint-through steel beams 21 and 22 having horizontal beam cores passing through the joint portion of the top 30a of the bundling member 30 are provided. And as these joint-through steel beams 21 and 22, there are provided a first steel beam 21 which is a secondary beam 2B having a horizontal beam core along the X direction passing through the joint portion, and a second steel beam 22 which is a main beam 2A having a beam core perpendicular to the joint portion of the top 30a with respect to the beam core of the first steel beam 21 and along the horizontal Y direction.

[0020] Further, the damper 11 is installed so as to have an axis along the X direction parallel to the beam core of the first steel beam 21 which is the cross beam 2B. That is, the beam core of the main beam 2A passing through the joint of the top 30a of the tendon member 30 in the superstructure 2 is parallel to the Y direction orthogonal to the axis of the damper 11, and the joint of the top 30a of the tendon member 30 in the superstructure 2 is a portion where there is no main beam having a beam core along the X direction parallel to the axis of the damper 11. And in such a configuration, the rigidity against the horizontal load transmitted from the damper 11 at the joint of the top 30a of the tendon member 30 is likely to decrease, and accordingly, the rigidity at the lower end 30b of the tendon member 30 may also decrease. Therefore, in the damper mounting structure 1A, auxiliary rigid members 41 and 42 for exhibiting relatively high rigidity are provided in order to favorably exhibit the vibration damping effect of the damper 11 at the lower end 30b of the tendon member 30.

[0021] The auxiliary rigid members 41 and 42 are composed of H-shaped steels in an inclined posture functioning as a strut, with one ends 41a and 42a joined to the lower end 30b of the tendon member 30 and the other ends 41b and 42b joined to the steel beams 21 and 22 passing through the joint. Then, even when a relatively large horizontal load is applied from the damper 11 to the lower end 30b of the tendon member 30, the horizontal displacement of the lower end 30b of the tendon member 30 is suppressed by the auxiliary rigid members 41 and 42 joined to the lower end 30b. That is, at the joints of the auxiliary rigid members 41 and 42 in the steel beams 21 and 22 passing through the joint, since the steel beams 21 and 22 passing through the joint have a horizontal beam core passing through the joint of the top 30a of the tendon member 30, the rigidity against the horizontal load parallel to the beam core becomes high. Therefore, by joining the auxiliary rigid members 41 and 42 to the lower end 30b of the tendon member 30 in a posture along the beam core of the steel beams 21 and 22 passing through the joint, the rigidity parallel to the beam core at the lower end 30b of the tendon member 30 is improved.

[0022] As the supplementary rigid members 41 and 42, there are provided a first supplementary rigid member 41 (see FIG. 2) provided in a posture along the X direction in which the beam cores of the first steel frame beams 21 are parallel, and a second supplementary rigid member 42 (see FIG. 3) provided in a posture along the Y direction in which the beam cores of the second steel frame beams 22 are parallel.

[0023] As shown in FIG. 2, the first supplementary rigid member 41 extends along the X direction parallel to the axial center of the damper 11 and is configured as a strut for enhancing the rigidity of the bundled member 30 in the X direction. That is, one end 41a of the first supplementary rigid member 41 is joined to the lower end portion 30b of the bundled member 30, and the other end 41b of the first supplementary rigid member 41 is joined to the first steel frame beam 21. By providing the first supplementary rigid member 41 extending along the X direction in this way, even when there is no large beam having a beam core parallel to the axial center of the damper 11 at the joint portion of the top portion 30a of the bundled member 30, the rigidity of the lower end portion 30b of the bundled member 30 in the X direction along the axial center of the damper 11 is improved. In addition, in the present embodiment, the first supplementary rigid member 41 is provided on the side where the damper 11 is disposed when viewed from the lower end portion 30b of the bundled member 30, but it can also be provided on the opposite side. Further, for example, when the dampers 11 are connected to both sides of the lower end portion 30b, the first supplementary rigid members 41 can also be provided on both sides of the lower end portion 30b.

[0024] The first supplementary rigid member 41 is composed of a bracket member 41A welded and joined to the side surface of the lower end portion 30b of the bundled member 30, a bracket member 41B welded and joined to the lower surface of the first steel frame beam 21, and a connecting member 41C whose both ends are bolted to them by a splice plate. The connection portions of the connecting member 41C in the bracket members 41A and 41B are composed of the same H-shaped steel as the connecting member 41C, and the connecting member 41C also composed of H-shaped steel is bolted to the portions composed of H-shaped steel in these bracket members 41A and 41B by a splice plate in a butted state. Note that the configuration of the first supplementary rigid member 41 can be appropriately changed. For example, the first supplementary rigid member 41 may be composed of an integral steel frame, and both ends thereof may be joined to the lower end portion 30b of the bundled member 30 and the first steel frame beam 21, respectively.

[0025] The first supplementary rigid member 41 is located above the damper 11 and extends along the X direction parallel to the axis of the damper 11. From this, when attaching and detaching the connecting pin 15A in the vertical posture to the connecting portion 15 of the damper 11 with respect to the lower end portion 30b of the bundle member 30 from the upper side, there may be a problem of interference with the first supplementary rigid member 41. Therefore, as shown in FIG. 6, the first supplementary rigid member 41 is composed of an H-shaped steel with both flanges 45 in a horizontal posture along the vertical plane. Further, on the lower end portion 30b side of the bundle member 30 in the web 46 of the first supplementary rigid member 41, a connecting pin insertion / removal hole 47 for attaching and detaching the connecting pin 15A in the vertical posture at the connecting portion 15 is formed. With this configuration, even when the one end 41a, which is the joint portion of the first supplementary rigid member 41 with respect to the connecting portion 15, is brought as close as possible to the connecting portion 15 of the damper 11 at the lower end portion 30b of the bundle member 30 in order to increase the rigidity of the connecting portion 15, the connecting pin 15A at the connecting portion 15 can be easily attached and detached from the upper side through the connecting pin insertion / removal hole 47 formed in the web 46 of the first supplementary rigid member 41 made of H-shaped steel in the horizontal posture.

[0026] As shown in FIG. 3, the second supplementary rigid member 42 extends along the Y direction orthogonal to the axis of the damper 11 and is configured as a strut for increasing the rigidity of the bundle member 30 in the Y direction. That is, one end 42a of the second supplementary rigid member 42 is joined to the lower end portion 30b of the bundle member 30, and the other end 42b of the second supplementary rigid member 42 is joined to the second steel frame beam 22. By providing the second supplementary rigid member 42 extending along the Y direction in this way, the rigidity of the lower end portion 30b of the bundle member 30 in the Y direction orthogonal to the axis of the damper 11 is improved. In addition, in the present embodiment, the second supplementary rigid member 42 is provided on both sides of the lower end portion 30b of the bundle member 30, but it can also be provided on one side.

[0027] The second supplementary stiffening member 42 is composed of a bracket member 42A made of a gusset plate welded and joined to the side surface of the lower end portion 30b of the bundling member 30, a bracket member 42B made of a gusset plate welded and joined to the lower surface of the second steel girder 22, and a connecting member 42C made of a channel steel bolted to both ends thereof. Note that the configuration of the second supplementary stiffening member 42 can be changed as appropriate. For example, the second supplementary stiffening member 42 may be composed of an integral steel frame, and both ends thereof may be joined to the lower end portion 30b of the bundling member 30 and the second steel girder 22, respectively.

[0028] 〔Second Embodiment〕 The detailed configuration of the damper mounting structure 1B of the second embodiment will be described with reference to FIGS. 4, 5, and 6. Note that, for the same configuration as that of the first embodiment described above, the same reference numerals will be used, and the description may be omitted. As shown in FIGS. 4 and 5, in the damper mounting structure 1B of the present embodiment, the top portion 30a of the bundling member 30 is bolted to a small beam 2B having a beam axis along the X direction via a bracket 31 made of a gusset plate. Further, the joint portion of the top portion 30a of the bundling member 30 in the small beam 2B is a location where the beam axis of a grandchild beam 2C having a beam axis parallel to the Y direction passes through. Note that this grandchild beam 2C is not connected to the small beam 2B to which the top portion 30a of the bundling member 30 is connected, but is connected to another adjacent small beam 2B. That is, in the superstructure 2, joint-through steel girders 21, 22 having a horizontal beam axis passing through the joint portion of the top portion 30a of the bundling member 30 are provided. And as these joint-through steel girders 21, 22, a first steel girder 21 which is a grandchild beam 2C having a beam axis along the horizontal Y direction passing through the joint portion, and a second steel girder 22 which is a small beam 2B having a beam axis along the horizontal X direction orthogonal to the beam axis of the first steel girder 21 at the joint portion of the top portion 30a are provided.

[0029] Further, the damper 11 is installed so as to have an axis along the Y direction parallel to the beam core of the first steel beam 21 which is the secondary beam 2C. That is, the beam core of the secondary beam 2B passing through the joint portion of the top 30a of the tendon member 30 in the superstructure 2 is parallel to the X direction orthogonal to the axis of the damper 11, and the joint portion of the top 30a of the tendon member 30 in the superstructure 2 is a portion where there is no large beam having a beam core along the Y direction parallel to the axis of the damper 11. And in such a configuration, the rigidity against the horizontal load transmitted from the damper 11 at the joint portion of the top 30a of the tendon member 30 is likely to decrease, and accordingly, the rigidity at the lower end portion 30b of the tendon member 30 may also decrease. Therefore, in the damper mounting structure 1B, auxiliary rigid members 41 and 42 for exhibiting relatively high rigidity are provided in order to favorably exhibit the vibration damping effect by the damper 11 at the lower end portion 30b of the tendon member 30.

[0030] The auxiliary rigid members 41 and 42 are composed of H-shaped steels in an inclined posture functioning as braces, with one ends 41a and 42a joined to the lower end portion 30b of the tendon member 30 and the other ends 41b and 42b joined to the steel beams 21 and 22 passing through the joint portion. Then, even when a relatively large horizontal load is applied from the damper 11 to the lower end portion 30b of the tendon member 30, the horizontal displacement of the lower end portion 30b of the tendon member 30 is suppressed by the auxiliary rigid members 41 and 42 joined to the lower end portion 30b. That is, at the joint portion of the auxiliary rigid members 41 and 42 in the steel beams 21 and 22 passing through the joint portion, since the steel beams 21 and 22 passing through the joint portion have a horizontal beam core passing through the joint portion of the top 30a of the tendon member 30, the rigidity against the horizontal load parallel to the beam core becomes high. Therefore, by joining the auxiliary rigid members 41 and 42 to the lower end portion 30b of the tendon member 30 in a posture along the beam core of the steel beams 21 and 22 passing through the joint portion, the rigidity parallel to the beam core at the lower end portion 30b of the tendon member 30 is improved.

[0031] As the supplementary rigid members 41 and 42, there are provided a first supplementary rigid member 41 (see FIG. 4) provided in a posture along the Y direction parallel to the beam core of the first steel frame beam 21, and a second supplementary rigid member 42 (see FIG. 5) provided in a posture along the X direction parallel to the beam core of the second steel frame beam 22.

[0032] As shown in FIG. 4, the first supplementary rigid member 41 extends along the Y direction parallel to the axial core of the damper 11 and is configured as a strut for enhancing the rigidity of the bundled member 30 in the Y direction. That is, one end 41a of the first supplementary rigid member 41 is joined to the lower end portion 30b of the bundled member 30, and the other end 41b of the first supplementary rigid member 41 is joined to the first steel frame beam 21. By providing the first supplementary rigid member 41 extending along the Y direction in this way, even when there is no large beam having a beam core parallel to the axial core of the damper 11 at the joint portion of the top portion 30a of the bundled member 30, the rigidity of the lower end portion 30b of the bundled member 30 in the Y direction along the axial core of the damper 11 is improved. In addition, in the present embodiment, the first supplementary rigid member 41 is provided on the side where the damper 11 is disposed as viewed from the lower end portion 30b of the bundled member 30, but it can also be provided on the opposite side. Further, for example, when dampers 11 are connected to both sides of the lower end portion 30b, the first supplementary rigid members 41 can also be provided on both sides of the lower end portion 30b.

[0033] The first supplementary rigid member 41 is composed of a bracket member 41A welded and joined to the side surface of the lower end portion 30b of the bundled member 30, a bracket member 41B welded and joined to the lower surface of the first steel frame beam 21, and a connecting member 41C whose both ends are bolted to them by a splice plate, in the same manner as in the first embodiment described above. Also, as shown in FIG. 6, the first supplementary rigid member 41 is composed of an H-shaped steel in a horizontal posture where both flanges 45 are along a vertical plane. Further, on the side of the lower end portion 30b of the bundled member 30 in the web 46 of the first supplementary rigid member 41, a connecting pin insertion / removal port 47 for inserting and removing the vertically oriented connecting pin 15A in the connecting portion 15 is formed.

[0034] As shown in Fig. 5, the second supplementary stiffening member 42 extends along the X direction orthogonal to the axis of the damper 11 and is configured as a strut for enhancing the rigidity of the bundling member 30 in the X direction. That is, one end 42a of the second supplementary stiffening member 42 is joined to the lower end portion 30b of the bundling member 30, and the other end 42b of the second supplementary stiffening member 42 is joined to the second steel frame beam 22. By providing the second supplementary stiffening member 42 extending along the X direction in this way, the rigidity of the lower end portion 30b of the bundling member 30 in the X direction orthogonal to the axis of the damper 11 is improved. In addition, in the present embodiment, the second supplementary stiffening member 42 is provided on one side of the lower end portion 30b of the bundling member 30, but it can also be provided on both sides.

[0035] Similar to the first embodiment described above, the second supplementary stiffening member 42 includes a bracket member 42A made of a gusset plate welded to the side surface of the lower end portion 30b of the bundling member 30, a bracket member 42B made of a gusset plate welded to the lower surface of the second steel frame beam 22, and a connecting member 42C made of a channel steel bolted to both ends thereof. Furthermore, as shown in Fig. 5, when a pair of bundling members 30 are arranged adjacent to each other, the respective second supplementary stiffening members 42 connected to the lower end portions 30b of these bundling members 30 are arranged to intersect, and the central portions of the respective second supplementary stiffening members 42 are joined to each other, so that the deformation of each second supplementary stiffening member 42 can be configured to suppress each other.

[0036] 〔Alternative Embodiment〕 Another embodiment of the present invention will be described. Note that the configurations of the respective embodiments described below are not limited to being applied alone, and can also be applied in combination with the configurations of other embodiments.

[0037] (1) In the above embodiment, the first supplementary rigid member 41 is constituted by an H-shaped steel with both flanges 45 in a horizontal posture along a vertical plane, and the connection pin insertion / removal hole 47 is formed in the web 46 of the first supplementary rigid member 41. However, within the range where the connection pin 15A in the connection portion 15 can be attached and detached, such a connection pin insertion / removal hole 47 can also be omitted. Further, when omitting the connection pin insertion / removal hole 47, the H-shaped steel constituting the first supplementary rigid member 41 may have a vertical posture with the web 46 conforming to the vertical plane, or the first supplementary rigid member 41 may be constituted by another steel material.

[0038] (2) In the above embodiment, the joint portion at the top 30a of the bundled member 30 in the upper structure 2 is set as a portion where there is no large beam having a beam axis parallel to the axis of the damper 11. However, it may be a portion where a large beam exists.

[0039] (3) In the above embodiment, a first supplementary rigid member 41 extending along a direction parallel to the axis of the damper 11 and a second supplementary rigid member 42 extending along a direction orthogonal to the axis of the damper 11 are provided with respect to the lower end portion 30b of one bundled member 30. However, for example, the second supplementary rigid member 42 along the direction in which the load applied from the damper 11 is relatively small can also be omitted.

Explanation of Reference Numerals

[0040] 1A, 1B Damper mounting structure 2 Upper structure 3 Seismic isolation layer 5 Lower structure 11 Damper 11a One end 11a End 15 Connection portion 15A Connection pin 21 First steel girder 22 Second steel girder 30 Bundled member 30a Top 30b Lower end portion 41 First supplementary rigid member (supplementary rigid member) 41a One end 41b The other end 42 Second supplementary rigid member (supplementary rigid member) One end of 42a The other end of 42b 45 Flange 46 Web 47 Connecting pin insertion / removal port

Claims

1. A damper mounting structure in which a damper in a horizontal posture is arranged in a seismic isolation layer between an upper structure and a lower structure, one end of which is rotatably connected to the upper structure around a vertical axis and the other end of which is rotatably connected to the lower structure around a vertical axis, comprising a steel frame bundle member having a top joined to the upper structure and extending downward, with one end of the damper rotatably connected to the lower end thereof around a vertical axis, in the upper structure, a steel frame beam passing through the joint is provided with a horizontal beam core passing through the joint portion at the top of the bundle member, A damper mounting structure comprising a supplementary rigid member in an inclined posture having one end joined to the lower end of the bundle member and the other end joined to the steel frame beam passing through the joint portion.

2. The supplementary rigid member is composed of an H-shaped steel with both flanges in a horizontal posture along a vertical plane, The damper mounting structure according to claim 1, wherein a connecting pin insertion / removal hole for inserting and removing a connecting pin in a vertical posture at the connecting portion of the damper with respect to the lower end of the bundle member is formed on the web of the supplementary rigid member on the lower end side of the bundle member.

3. The damper mounting structure according to claim 1 or 2, wherein the joint portion at the top of the bundle member in the upper structure is a portion where there is no large beam having a beam core parallel to the axis of the damper.

4. In the upper structure, as the steel frame beam passing through the joint portion, a first steel frame beam having a horizontal beam core passing through the joint portion at the top of the bundle member and a second steel frame beam having a horizontal beam core orthogonal to the beam core of the first steel frame beam at the joint portion at the top of the bundle member are provided, The damper mounting structure according to claim 1 or 2, comprising a first supplementary rigid member having one end joined to the lower end of one of the bundle members and the other end joined to the first steel frame beam, and a second supplementary rigid member having the other end joined to the second steel frame beam.

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