Seismic response control frame

Abstract

To provide a seismic response control frame, etc. capable of suitably reducing a seismic force burden on a main structure.SOLUTION: A seismic response control frame 1 has a main structure 10, a suspended floor structure 20, and a vibration damping mechanism for damping vibrations of the suspended floor structure 20. The main structure 10 includes a vertical section 11 and a transverse section 12 supported by the vertical section 11. The suspended floor structure 20 includes a connection material 21 extending downward from the transverse section 12 and a vibrating floor section 22 suspended and supported by the connection material 21, and is capable of vibrating in a horizontal direction. A clearance is provided between the vibrating floor section 22 and the vertical section 11, and a natural period of the suspended floor structure 20 is greater than or equal to a natural period of the main structure 10.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a seismic control structure and the like. [Background technology]

[0002] There is a need to avoid obstacles such as existing buildings and build a new building only in the upper space. For example, this may be the case when the existing building is a historical structure that needs to be preserved, or when the existing building will eventually be demolished but it is desired to continue using the existing building until the extension is completed. In other cases, a new building may be constructed with a large space such as a hall or pilotis underneath.

[0003] In these cases, even if a new building is constructed, a normal column-beam structure would interfere with obstacles, halls, pilotis spaces, etc. (referred to as obstacles, etc.) Therefore, as shown in Fig. 8, it is conceivable to construct a main structure with structural columns 101 erected so as to sandwich obstacles 110, etc., and girders 102 with a large span between them, and to support floors 104, etc. of the upper space from the girders 102 via hanging members 103 such as H-shaped steel.

[0004] With a structure like that shown in Fig. 8, a column-free space can be easily formed under the building, and functional advantages such as avoiding interference with obstacles 110 and utilizing it as a hall or pilotis space can be realized. Also, the hanging members 103 become tension members and compression does not need to be considered, so the cross-sectional size is small and the space above the floor 104 can be used effectively. Furthermore, the construction range of the foundation 105 can be concentrated around the structural columns 101.

[0005] Patent document 1 also describes how a secondary structure including a floor, etc. is suspended inside a main structure consisting of pillars, beams, etc., thereby lengthening the natural period of the main structure and reducing the vibration energy input to the structure. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2001-73584 A Summary of the Invention [Problem to be solved by the invention]

[0007] In the structure shown in Fig. 8, the main structure must bear all of the seismic force, so the structural columns 101 and their foundations 105 are over-designed and the cross-sectional size is large. This causes problems such as a reduction in the volume of space above the floor 104 and an increase in costs due to the increase in the number of framework members.

[0008] In addition, in Patent Document 1, the deformation of the primary structure increases as the natural period of the primary structure increases, making it difficult to attach exterior materials to the primary structure, which limits the design. In fact, Patent Document 1 has a special configuration in which exterior materials are attached not to the primary structure but to the secondary structure inside it.

[0009] The present invention has been made in consideration of the above problems, and has an object to provide a seismic control structure etc. that can suitably reduce the seismic force load on the main structure. [Means for solving the problem]

[0010] In order to solve the above-mentioned problems, the present invention provides a seismic control structure comprising a main structure including a vertical section and a horizontal section supported by the vertical section, a suspended floor structure capable of vibrating in a horizontal direction, the suspended floor structure including a connecting member extending downward from the horizontal section and a vibrating floor section suspended and supported by the connecting member, and a vibration damping mechanism for damping vibration of the suspended floor structure, wherein a clearance is provided between the vibrating floor section and the vertical section, and the natural period of the suspended floor structure is greater than or equal to the natural period of the main structure.

[0011] In the present invention, the suspended floor structure is suspended from the main structure so that it can vibrate horizontally like a pendulum, and the natural period of the suspended floor structure is set to be equal to or greater than the natural period of the main structure. A vibration damping mechanism is provided to damp the vibration of the suspended floor structure, allowing the suspended floor structure to function as a Tuned Mass Damper (TMD), and the seismic force acting on the main structure can be reduced. This allows the cross-sectional size of the vertical part of the main structure and its foundation to be reduced, making it easier to secure the spatial volume above the floor, and reducing the amount of structure required to reduce costs. In addition, since the vibrating floor part can be suspended in the air, a column-free space can be formed below it. In addition, since the natural period of the main structure is short, it is also possible to attach exterior materials to the main structure.

[0012] It is preferable that a fixed floor section fixed to the vertical section is provided below the vibrating floor section, and the connecting material is connected to the fixed floor section. Alternatively, it is preferable that a fixed floor section fixed to the vertical section is provided above the vibrating floor section, and the connecting material is connected to the fixed floor section. It is also preferable that the vibrating floor sections in multiple levels above and below are fixed and vibrate as a unit. These configurations make it possible to shorten the effective length of the pendulum, shorten the natural period of the suspended floor structure, and bring it closer to the natural period of the main structure, thereby enhancing the TMD effect.

[0013] It is desirable that the connecting material is not arranged at a height corresponding to the lower part of the vertical portion, but is arranged only above the lower part. This allows the creation of a column-free space beneath the building, making it possible to construct new buildings while avoiding obstacles such as existing buildings, or to use the space as a large space such as a hall or pilotis.

[0014] It is also preferable that an elastic body be provided between the vibrating floor portion and the vertical portion. This also makes it possible to shorten the natural period of the vibrating floor and enhance the TMD effect. Effect of the Invention

[0015] According to the present invention, it is possible to provide a seismic control frame etc. that can suitably reduce the seismic force burden on the main structure. [Brief description of the drawings]

[0016] [Figure 1] FIG. [Diagram 2] FIG. 2 is a plan view of the vibrating floor 22. [Diagram 3] A diagram showing seismic isolation structures 1a, 1b, and 1c. [Figure 4] A diagram showing seismic isolation structure 1d. [Diagram 5] FIG. [Figure 6] A diagram showing seismic isolation structure 1e. [Figure 7] A diagram showing seismic isolation structures 100, 100a, 100b, and 100c. [Figure 8] An example of a structure supporting a floor 104 etc. from a girder 102 via a hanging member 103. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

[0018] 1 is a diagram showing a vibration-damping structure 1 according to an embodiment of the present invention. The vibration-damping structure 1 of this embodiment is a building having a main structure 10 and a suspended floor structure 20, and further includes a vibration damping mechanism 30 for damping vibrations of the suspended floor structure 20.

[0019] The main structure 10 includes a vertical portion 11 and a horizontal portion 12 supported by the vertical portion 11 .

[0020] The vertical part 11 is a columnar member provided on the outer periphery of the building, such as a structural column, but is not limited to this. For example, it may be a core having a vertical line of movement inside, such as an elevator shaft or a staircase. The vertical part 11 is rigidly connected and fixed to a foundation 13 underground.

[0021] The horizontal section 12 is a member that is bridged between the vertical sections 11 located on both sides of the building, and is, for example, a girder, but is not limited to this.

[0022] The vertical section 11 and the horizontal section 12 may be made of steel (S) or reinforced concrete (RC). If the vertical section 11 and the horizontal section 12 are made of steel, they may be made of a single member or may be made of multiple members such as a truss column or truss beam.

[0023] The suspended floor structure 20 includes a connecting member 21 extending downward from the horizontal section 12, and a vibrating floor section 22 suspended and supported by the connecting member 21. The connecting member 21 is not disposed at a height that corresponds to the lower part of the vertical section 11, but is disposed only above the lower part.

[0024] Steel materials such as H-shaped steel are used for the connecting members 21. However, the connecting members 21 are not limited to this, and for example, steel wires may be used. The connecting members 21 may be a single continuous member, or may be a combination of multiple steel materials. Furthermore, the type of joint between the cross section 12 and the connecting members 21 is not particularly important, but if the rigidity ratio of the connecting members 21 to the cross section 12 is small, the joint will behave like a pin joint, and if the rigidity ratio is large, the joint will behave like a rigid joint.

[0025] 2 is a diagram showing a plan view of the vibrating floor 22. The vibrating floor 22 is provided with a horizontal clearance C from the vertical part 11, and can vibrate in a pendulum-like manner in the horizontal direction. The vibrating floor 22 is a slab made of reinforced concrete, but is not necessarily limited to this and may be a wooden floor or the like. In either case, a small beam or joist (not shown) can be attached to the connecting member 21, and the vibrating floor 22 can be placed on top of it. In some cases, the small beam or joist may be omitted.

[0026] The vibration damping mechanism 30 is provided between the vibrating floor section 22 and the vertical section 11, and damps the vibration of the suspended floor structure 20. The vibration damping mechanism 30 is, for example, an oil damper, but is not limited to this, and a friction damper, a steel damper, a viscoelastic damper, etc. may also be used. Even if the upper part of the vibrating floor section 22 is used as a living space, there is no concern that the vibrating floor section 22 will wobble unsteadily on a daily basis and affect the physical sensation of the occupants, because the damper has friction.

[0027] In this embodiment, the natural period of the suspended floor structure 20 is the same as or greater than the natural period of the main structure 10, and by connecting the vibrating floor section 22 and the vertical section 11 with a vibration damping mechanism 30, the suspended floor structure 20 itself behaves as a TMD (Tuned Mass Damper), reducing vibrations caused by earthquakes, etc. The natural period of the suspended floor structure 20 can be calculated from the rigidity and mass of the system consisting of the connecting member 21 and the vibrating floor section 22, and the natural period of the main structure 10 can be calculated from the rigidity and mass of the system consisting of the vertical section 11 and the cross section 12.

[0028] The size of the clearance C is not particularly limited, but can be set to about 5 cm as a reasonable value taking into consideration the fit of the flooring material. The upper part of the clearance C is covered with a cover (not shown) that can follow the displacement of the vibrating floor 22. Furthermore, the exterior material of the building (not shown) can be attached to either the outer main structure 10 or the inner suspended floor structure 20, but when attaching the exterior material to the inner suspended floor structure 20, the weatherstripping must also have details that can follow the displacement of the vibrating floor 22, and so-called locking mechanisms, sliding mechanisms, etc. can be applied.

[0029] Furthermore, the building to which the vibration control structure 1 is applied is a mid-rise building with a height of, for example, less than 60 m. This is because in high-rise buildings, the natural period of the suspended floor structure 20 becomes longer, making it difficult to keep the amplitude within a reasonable clearance C. Furthermore, if the vibration control structure 1 is a low-rise building with a height of around two stories, the benefits of applying the present invention become smaller.

[0030] As described above, in this embodiment, the suspended floor structure 20 is suspended from the main structure 10 so that it can vibrate horizontally like a pendulum, the natural period of the suspended floor structure 20 is set to be equal to or greater than the natural period of the main structure 10, and a vibration damping mechanism 30 is provided to damp the vibration of the suspended floor structure 20, so that the suspended floor structure 20 can function as a Tuned Mass Damper (TMD), and the seismic force acting on the main structure 10 can be reduced. Therefore, the cross-sectional size of the vertical part 11 of the main structure 10 and its foundation 13 can be reduced, making it easier to secure the spatial volume above the floor, and the cost can be reduced by reducing the number of frameworks. In addition, since the vibrating floor section 22 can be suspended in the air, a column-free space can be formed in the lower part of the building below the vibrating floor section 22, which makes it possible to build a new building while avoiding obstacles such as existing buildings, or to use it as a large space such as a hall or a piloti. In addition, since the natural period of the main structure 10 is short, it is also possible to attach exterior materials to the main structure 10.

[0031] However, the present invention is not limited to the above embodiment. For example, as shown in the suspended floor structure 20a of the seismic isolation frame 1a in Fig. 3(a), only the floor of the lower part of the building may be a vibrating floor part 22, and the floor above it may be a fixed floor part 40 that is fixed to the vertical part 11 (does not vibrate), and a connecting member 21 may be connected to the fixed floor part 40.

[0032] The natural period of the suspended floor structure 20, which swings like a pendulum, tends to be larger than the natural period of the main structure 10; however, as described above, by fixing the floor of the upper part of the building to the vertical part 11 and isolating the floor of the lower part of the building from the vertical part 11 and allowing it to vibrate, the effective length L of the pendulum can be shortened, and the natural period of the suspended floor structure 20a can be shortened to approach the natural period of the main structure 10, thereby enhancing the TMD effect.

[0033] As described above, only some of the floors of a building may be the vibrating floor section 22, but as shown in the suspended floor structure 20b of the seismic isolation frame 1b in Fig. 3(b), the floor in the lower part of the building may be the fixed floor section 40, and the floor above that may be the vibrating floor section 22, with the connecting member 21 connected to the fixed floor section 40. In this case, too, by shortening the effective length L of the pendulum, the TMD effect can be enhanced, as described above.

[0034] In the case of Fig. 3(b), compared to the example of Fig. 3(a), the lower part of the connecting material 21 is fixed to the fixed floor part 40, so that the tension of the connecting material 21 supporting the vibrating floor part 22 is increased, and the natural period of the vibrating floor part 22 can be shortened further. Also, when the floor of the upper part of the building is made the vibrating floor part 22, it is easy to ensure a large TMD mass ratio. Furthermore, the vibration-resistant structure 1a in Fig. 3(a) requires weatherproofing for the column-free space of the vibrating floor part 22 on the lowest floor, but the vibration-resistant structure 1b in Fig. 3(b) has the advantage that such weatherproofing is unnecessary or can be reduced.

[0035] As shown in the suspended floor structure 20c of the vibration control frame 1c in Fig. 3(c), multiple upper and lower stages of vibrating floors 22 may be connected by structural members 23 such as braces so that these vibrating floors 22 vibrate as a unit. This also shortens the effective length L of the pendulum, thereby enhancing the TMD effect. However, since the structural members 23 are inserted into the space above the vibrating floors 22 in the vibration control frame 1c, the above-mentioned vibration control frames 1a and 1b are preferable in terms of effective use of the space above the vibrating floors 22.

[0036] Furthermore, in this embodiment, the vibrating floor section 22 is supported by connecting members 21 from the cross sections 12 at the upper end of the vertical section 11, but as shown in the main structure 10d of the seismic isolation structure 1d in Figure 4, a cross section 12 may be added to the middle section in the height direction of the vertical section 11, and the vibrating floor section 22 may be suspended and supported from each of the multiple cross sections 12 by connecting members 21, thereby forming a multiple-story suspended floor structure 20.

[0037] Furthermore, in order to further enhance the TMD effect of the suspended floor structure 20, an elastic body 24 made of laminated rubber may be disposed between the vertical section 11 and the vibrating floor section 22, as shown in Fig. 5(a), in addition to the vibration damping mechanism 30. Fig. 5(a) shows a cross section of the vibrating floor section 22 in the thickness direction, along the vibration direction of the vibrating floor section 22 (corresponding to the left-right direction in Fig. 5(a)).

[0038] In this case, the rigidity of the elastic body 24 can shorten the natural period of the suspended floor structure 20 and enhance the TMD effect. The elastic body 24 can also suppress daily micro-vibrations of the vibrating floor section 22, making the space above the floor more comfortable to use.

[0039] 5(a), the weight of the vibrating floor 22 is placed on the vertical part 11, so that the vibrating floor 22 is slidably arranged on a protruding piece 111 protruding from the vertical part 11. The elastic body 24 can be arranged by being sandwiched between the vibrating floor 22 and the protruding piece 111.

[0040] The elastic body 24 is not limited to laminated rubber. For example, Fig. 5(b) shows an example in which a coil spring is used as the elastic body 24a. The direction of expansion and contraction of the coil spring is the direction of vibration of the vibrating floor 22. Both ends of the coil spring are connected to an upward protrusion 112 provided on the protruding piece 111 and a downward protrusion 221 provided on the vibrating floor 22.

[0041] In this embodiment, the vertical portion 11 of the main structure 10 is provided on the outer periphery of the building, but as shown in the main structure 10e of the seismic isolation structure 1e in Fig. 6(a), the vertical portion 11 may be provided inside the building. The horizontal portion 12 is disposed so as to protrude laterally from the vertical portion 11. Reference numeral 14 in Fig. 6(a) denotes an exterior material such as a curtain wall provided on the outer periphery of the building.

[0042] FIG. 6(b) is a plan view of the vibrating floor 22 of the suspended floor structure 20e of the seismic isolation frame 1e. In this example, a clearance C is provided between the edge of the central opening 222 of the vibrating floor 22 and the vertical part 11.

[0043] Additionally, as shown in the vibration control frame 100 in Fig. 7(a), in order to secure a column-free space in the upper part of the building, a floor support structure 200 in which a vibrating floor section 22 below the topmost floor part in the main structure 10 is supported by post columns 21a may be applied instead of the suspended floor structure 20. As in the above, a clearance is provided between the vibrating floor section 22 and the vertical section 11, and a vibration damping mechanism 30 for damping the vibration of the vibrating floor section 22 is also provided in the same manner as in the above. Since the post columns 21a do not bear horizontal forces, the cross-sectional size can be made small.

[0044] As shown in the vibration-damping structures 100a to 100c in Fig. 7(b) to Fig. 7(d), the configurations described in Fig. 3(a) to Fig. 3(c) can also be applied to the floor support structures 200a to 200c. That is, in the floor support structure 200a of the vibration-damping structure 100a in Fig. 7(b), the floor of the lower part of the building is the vibrating floor part 22, the floor above it is the fixed floor part 40, and the post column 21a is connected to the fixed floor part 40. In addition, in the floor support structure 200b of the vibration-damping structure 100b in Fig. 7(c), the floor of the upper part of the building is the vibrating floor part 22, the floor below it is the fixed floor part 40, and the post column 21a is connected to the fixed floor part 40. In addition, in the floor support structure 200c of the vibration-damping structure 100c in Fig. 7(d), the upper and lower multiple stages of the vibrating floor part 22 are integrated with the structural member 23.

[0045] Although the preferred embodiment of the present invention has been described above with reference to the accompanying drawings, the present invention is not limited to the above examples. It is clear that a person skilled in the art can come up with various modified or altered examples within the scope of the technical ideas disclosed in this application, and it is understood that these also naturally belong to the technical scope of the present invention. [Explanation of symbols]

[0046] 1, 1a, 1b, 1c, 1d, 1e, 100, 100a, 100b, 100c: Vibration control frame 10, 10d, 10e: Main structure 11: Vertical section 12:Horizontal section 20, 20a, 20b, 20c, 20e: Suspended floor structure 21: Connector 21a: Post Pillar 22: Vibrating floor section 23: Structural members 24, 24a: Elastic body 30: Vibration damping mechanism 40:Fixed floor part 200, 200a, 200b, 200c: Floor support structure

Claims

1. A main structure including a vertical portion and a horizontal portion supported by the vertical portion; a suspended floor structure capable of being vibrated in a horizontal direction, the suspended floor structure including a connecting member extending downward from the horizontal frame portion and a vibrating floor portion suspended and supported by the connecting member; a vibration damping mechanism for damping vibrations of the suspended floor structure; having A clearance is provided between the vibrating floor portion and the vertical portion, A seismic control structure, characterized in that the natural period of the suspended floor structure is equal to or greater than the natural period of the main structure.

2. a fixed floor portion fixed to the vertical portion is provided below the vibrating floor portion, 2. The seismic control structure according to claim 1, wherein the connecting member is connected to the fixed floor portion.

3. a fixed floor portion fixed to the vertical portion is provided above the vibrating floor portion, 2. The seismic control structure according to claim 1, wherein the connecting member is connected to the fixed floor portion.

4. 2. The vibration control structure according to claim 1, wherein the vibrating floor sections in the upper and lower stages are fixed together and vibrate as a unit.

5. 2. The seismic isolation structure according to claim 1, wherein the connecting members are not arranged at a height corresponding to the lower part of the vertical portion, but are arranged only above the lower part.

6. 2. The vibration control structure according to claim 1, further comprising an elastic body provided between said vibrating floor portion and said vertical portion.

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