JP7611066B2 - Damper - Google Patents

Description

The present invention relates to a damper.

In seismically isolated and vibration-controlled buildings, dampers are an important element, absorbing the vibration energy generated in the building during an earthquake and providing a damping effect to the building. Traditionally, these dampers have been required to exhibit stable hysteresis characteristics regardless of the magnitude of deformation of the building. A wide variety of dampers that can achieve this have been developed, including buckling-stiffened steel dampers, viscoelastic dampers, and oil dampers. For example, Patent Document 1 discloses a damping mechanism composed of multiple curved members made of elastoplastic material.

JP 2000-104787 A

On the other hand, there is a growing concern that excessive inputs to buildings due to earthquakes that exceed the design level may cause excessive deformation in buildings, and this is being called for.

However, the damping mechanism in Cited Document 1 cannot suppress excessive deformation in a building caused by excessive input to the building, so it is necessary to provide a separate means for suppressing excessive deformation, which requires space and costs.

Taking the above facts into consideration, the present invention aims to provide a damper that can suppress excessive deformation caused in a building when an excessive input is applied to the building.

The damper according to the first embodiment is configured by arranging a pair of metallic damper units on the same plane, each unit having two parallel straight sections and a curved section connecting the ends of the two straight sections, with the tops of the curved sections of the pair of damper units connected to each other.

According to the damper of the first aspect, the damper is attached between a first structure and a second structure that move relative to each other. That is, one end of a straight section provided on each of a pair of damper units arranged on the same plane is fixed to the first structure, and the other end of a straight section is fixed to the second structure.

During small displacements, where the first structure and the second structure move relatively small in the in-plane direction, the pair of damper units undergo elastoplastic deformation in such a way that the strain generated in these damper units is dispersed rather than concentrated locally. This allows the damper to exhibit stable hysteresis characteristics, absorb vibration energy, and attenuate the relative movement between the first structure and the second structure (the shaking of the second structure relative to the first structure).

In addition, during medium displacement, when the first structure and the second structure move relatively more in the in-plane direction than during small displacement, the damper exhibits stable hysteresis characteristics similar to those during small displacement, and is able to absorb vibration energy and damp the relative movement between the first structure and the second structure (the shaking of the second structure relative to the first structure).

Furthermore, when the first and second structures move excessively relative to each other in the in-plane direction, the curved portions that connect each of the pair of damper units become straight and resist like a tension brace material, causing the damper to exhibit hardening hysteresis characteristics. This makes it possible to suppress excessive relative movement between the first and second structures (excessive displacement of the second structure relative to the first structure). In other words, it is possible to suppress excessive deformation occurring in the building in response to excessive input force to the building.

The damper according to the second aspect is the damper according to the first aspect, in which the curved portion is formed in an arc shape.

In the damper according to the second aspect, the curved portion is formed in an arc shape, resulting in a smooth shape, which allows the distortion generated in the damper unit to be dispersed without being concentrated locally, thereby enabling the damper to exhibit more stable hysteresis characteristics.

The damper according to the third aspect is the damper according to the first or second aspect, in which an end of the straight section of one of the damper units is fixed to the upper surface of a lower column constituting a partition wall arranged on a vibration-damping floor of a building, and an end of the straight section of the other of the damper units is fixed to the lower surface of an upper column constituting the partition wall and arranged above the lower column at a distance from the lower column.

The damper according to the third aspect can be used as a vibration damper installed in the middle of the stud.

The present invention has the above-mentioned configuration, so it is possible to provide a damper that can suppress excessive deformation occurring in a building in response to excessive input to the building.

FIG. 2 is an elevational view of a damper according to one embodiment. FIG. 2 is a perspective view showing a damper according to an embodiment. 3(a) to 3(c) are elevation views showing variations in the shape of a damper according to one embodiment. FIG. 13 is an elevation view showing a damper as a comparative example. This is a cross-sectional view taken along line 5-5 in Figure 4. 6(a) to (c) are elevation views showing changes in the shape of a damper as a comparative example. FIG. 13 is a diagram illustrating a numerical analysis result of a damper according to an embodiment. FIG. 13 is a diagram showing the results of a numerical analysis of a damper as a comparative example. FIG. 11 is an elevational view showing a variation of a damper according to an embodiment. This is a cross-sectional view taken along line 10-10 in Figure 9. 11A to 11C are perspective views showing variations of a damper according to an embodiment. 12(a) to (e) are elevation views showing variations of a damper according to one embodiment. FIG. 11 is an elevation view showing a variation in the arrangement of the damper according to the embodiment. 11A to 11C are plan views showing variations in the arrangement of dampers according to an embodiment. 11A to 11C are plan views showing variations in the arrangement of dampers according to an embodiment.

The following describes a damper according to one embodiment, with reference to the drawings.

(Damper)
As shown in the elevational view of Fig. 1, the damper 10 is provided in a building 12, which is a vibration-controlled building, and is disposed on a vibration-controlled floor 14 formed between a floor slab 100, which is a lower structure as one structure, and a beam 104, which is an upper structure as a second structure, both of which are constructed so as to be relatively movable in the horizontal direction. The damper 10 is disposed between a lower column 16, which is disposed on the floor slab 100 and constitutes a partition wall 102, and an upper column 18, which is disposed below the beam 104 and constitutes the partition wall 102, and functions as a vibration-controlled damper.

As shown in the perspective view of FIG. 2, the damper 10 has two straight sections 20, 22 arranged horizontally above and below so as to be parallel, and a curved section 24 arranged so as to be convex in the horizontal direction and connecting the ends of the two straight sections 20, 22, and has a pair of damper units 26A, 26B arranged in the same plane.

The pair of damper units 26A, 26B are arranged so that the curved portions 24 of each are convex in opposite directions. The damper 10 is constructed by connecting the apexes of the curved portions 24 of the pair of damper units 26A, 26B.

In the following description, the direction in the same plane in which the pair of damper units 26A, 26B are arranged is referred to as the "in-plane direction X." In other words, the damper 10 is arranged so that the straight line portions 20, 22 are arranged horizontally along the in-plane direction X.

The damper units 26A and 26B are metal members made of steel, and the curved portion 24 is formed in an arc shape. In addition, the tops of the curved portions 24 of the pair of damper units 26A and 26B are joined together by welding.

As shown in FIG. 1, the damper 10 is provided between the lower column 16 and the upper column 18 by fixing the end 36 of one straight section 22 of each of the pair of damper units 26A, 26B to a base plate 28 provided on the upper surface of the lower column 16 with a bolt 32, and fixing the end 34 of the other straight section 20 of each of the pair of damper units 26A, 26B to a base plate 30 provided on the lower surface of the upper column 18 with a bolt 32.

(effect)
Next, the effects of this embodiment will be described.

The elevation views of Figures 3(a) to (c) show the shape of the damper 10 that has been deformed due to the relative movement of the floor slab 100 and the beam 104 in the horizontal direction of the in-plane direction X (see Figure 1), where the shape of the damper 10 before deformation is shown by a dashed dotted line and the shape of the deformed damper 10 is shown by a solid line.

According to the damper 10 of this embodiment, as shown in FIG. 3(a), during small displacement in which the floor slab 100 and the beam 104 move relatively slightly in the horizontal direction of the in-plane direction X, the lower column 16 and the upper column 18 move relatively slightly in the horizontal direction of the in-plane direction X. As a result, the pair of damper units 26A, 26B undergo elastic-plastic deformation in such a way that the strain generated in these damper units 26A, 26B is dispersed without being locally concentrated.

As a result, the damper 10 exhibits stable hysteresis characteristics, absorbs vibration energy, and damps the relative movement between the floor slab 100 and the beam 104 (displacement of the vibration-damping floor 14). This allows damping of the shaking of the building 12.

Furthermore, as shown in FIG. 3(b), during medium displacement, in which the floor slab 100 and the beam 104 move relatively more in the horizontal direction of the in-plane direction X than during small displacement, the lower column 16 and the upper column 18 move relatively more in the horizontal direction of the in-plane direction X than during small displacement. As a result, the damper 10 exhibits stable hysteresis characteristics similar to those during small displacement, and can absorb vibration energy and damp the relative movement between the floor slab 100 and the beam 104 (displacement of the vibration-damping floor 14). Therefore, the shaking of the building 12 can be damped.

Furthermore, as shown in FIG. 3(c), when the floor slab 100 and the beam 104 move excessively relative to each other in the horizontal direction of the in-plane direction X, the lower column 16 and the upper column 18 move excessively relative to each other in the horizontal direction of the in-plane direction X. As a result, the curved sections 24 that are provided on each of the pair of damper units 26A, 26B and connect to each other become straight (hereinafter, the straight-lined portions of the connected curved sections 24 are referred to as "straight sections 38"), and resist like a tensile brace material. At this time, the axial stiffness of the straight sections 38 contributes greatly to this resistance, and the damper 10 exhibits hardening hysteresis characteristics.

In addition, when the direction of movement of the upper column 18 relative to the lower column 16 changes to the opposite side and the deformation of the straight section 38 returns, the curved sections 24 (in the example of FIG. 3(c), the member 40 constituting the upper half of the curved section 24 of the damper unit 26A and the member 42 constituting the lower half of the curved section 24 of the damper unit 26B) provided above and below this straight section 38 prevent the damper units 26A and 26B from buckling, and the damper 10 exhibits the same hardening hysteresis characteristics when the upper column 18 moves to the opposite side relative to the lower column 16 as when the upper column 18 moves to the further side relative to the lower column 16.

These features make it possible to suppress excessive relative movement between the floor slab 100 and the beams 104 in the horizontal direction of the in-plane direction X (excessive displacement of the vibration-controlled floor 14). In other words, excessive deformation occurring in the building 12 in response to excessive input to the building 12 can be suppressed. In addition, since there is no need to provide a means for suppressing excessive deformation occurring in the building 12 separately from the damper 10, there is no need to incur space or costs for providing a separate means for suppressing excessive deformation occurring in the building 12.

In addition, according to the damper 10 of this embodiment, as shown in FIG. 2, the curved portion 24 is formed in an arc shape, resulting in a smooth shape, which allows the distortion generated in the damper units 26A and 26B to be dispersed without being concentrated locally, thereby allowing the damper 10 to exhibit more stable hysteresis characteristics.

Here, we show the results of a numerical analysis of the damper 10 of this embodiment and the damper 44 as a comparative example, which was performed to confirm the effect of the damper 10 of this embodiment.

As shown in the elevational view of FIG. 4 and in FIG. 5, which is a cross-sectional view taken along line 5-5 of FIG. 4, the damper 44 as a comparative example is configured by arranging the damper units 26A and 26B that constitute the damper 10 side by side. The damper units 26A and 26B are spaced apart such that the straight portions 20 and 22 are arranged horizontally along the in-plane direction X, and the curved portion 24 of the damper unit 26A is not connected to the curved portion 24 of the damper unit 26B.

The damper 44 is provided between the lower column 16 and the upper column 18 by fixing the end of one of the straight sections 22 provided on each of the damper units 26A and 26B to a base plate 46 provided on the upper surface of the lower column 16 with a bolt 32, and fixing the end of the other straight section 20 provided on each of the damper units 26A and 26B to a base plate 48 provided on the lower surface of the upper column 18 with a bolt 32.

The elevation views of Figures 6(a) to (c) show the shape of the damper 44 that has been deformed due to the relative movement of the floor slab 100 and the beam 104 in the horizontal direction of the in-plane direction X (see Figure 4). The shape of the damper 44 before deformation is shown by a dashed line, and the shape of the deformed damper 44 is shown by a solid line.

In the damper 44, the damper units 26A and 26B undergo elastic-plastic deformation in such a way that the strain generated in the damper units 26A and 26B is dispersed rather than concentrated locally, during small displacements (Figure 6(a)) in which the floor slab 100 and the beam 104 move relatively slightly relative to the horizontal direction of the in-plane direction X, during medium displacements (Figure 6(b)) in which the floor slab 100 and the beam 104 move relatively more relative to the horizontal direction of the in-plane direction X than during small displacements, and during large displacements (Figure 6(c)) in which the floor slab 100 and the beam 104 move excessively relative to the horizontal direction of the in-plane direction X.

This allows the damper 44 to exhibit stable hysteresis characteristics, absorb vibration energy, and damp the relative movement between the floor slab 100 and the beam 104 (displacement of the vibration-damping floor 14).

However, even when the floor slab 100 and the beam 104 undergo a large relative displacement in the horizontal direction of the in-plane direction X (Figure 6 (c)), the damper 44 does not exhibit hardening hysteresis characteristics because the damper units 26A and 26B undergo elastic-plastic deformation. Therefore, it is not possible to suppress the excessive relative movement between the floor slab 100 and the beam 104 in the horizontal direction of the in-plane direction X (excessive displacement of the vibration control floor 14).

The graph in Figure 7 shows the value 50 of the horizontal load (vertical axis) in the in-plane direction X generated on the damper 10 against the horizontal displacement (horizontal axis) in the in-plane direction X of the damper 10, determined by numerical analysis of the damper 10 (see Figure 1).

Of the 50 values, value 50A is the value when the damper 10 is subjected to a small displacement in the in-plane direction X, value 50B is the value when the damper 10 is subjected to a medium displacement in the in-plane direction X, and value 50C is the value when the damper 10 is subjected to a large displacement in the in-plane direction X.

The value of 50A indicates that the damper 10 exhibits stable hysteresis characteristics during small displacements.

The value of 50B also indicates that the damper 10 exhibits stable hysteresis characteristics during medium displacement.

Furthermore, the value of 50C indicates that the damper 10 exhibits hardening hysteresis characteristics during large displacements.

The graph in Figure 8 shows the value 52 of the horizontal load (vertical axis) in the in-plane direction X generated on the damper 44 against the horizontal displacement (horizontal axis) in the in-plane direction X of the damper 44, determined by numerical analysis of the damper 44 (see Figure 4).

Among the values 52, value 52A is the value when the damper 44 is subjected to a small displacement in the in-plane direction X, value 52B is the value when the damper 44 is subjected to a medium displacement in the in-plane direction X, and value 52C is the value when the damper 44 is subjected to a large displacement in the in-plane direction X.

The value 52A shows that the damper 44 exhibits stable hysteresis characteristics during small displacements.

The value 52B also indicates that the damper 44 exhibits stable hysteresis characteristics during medium displacement.

Furthermore, the value 52C indicates that during large displacements, the damper 44 exhibits stable hysteresis characteristics and does not exhibit hardening hysteresis characteristics.

In addition, from the value 50 in FIG. 7 and the value 52 in FIG. 8, it can be seen that the horizontal load in the in-plane direction X generated in the dampers 10 and 44 is greater for the damper 10 than for the damper 44. This shows that since the damper 10 can withstand a large horizontal load, it is possible to reduce the number of dampers installed on the vibration control floors 14 of the building 12.

(Modification)
Next, a modification of the above embodiment will be described.

In the above embodiment, as shown in Figures 1 and 2, an example was shown in which the tops of the curved portions 24 of a pair of damper units 26A, 26B were joined together by welding to form the damper 10, but it is sufficient that the pair of damper units 26A, 26B are connected.

For example, the apexes of the curved portions 24 of the pair of damper units 26A, 26B may be joined together using another joining method, or the pair of damper units 26A, 26B may be cut out as a single unit from a plate material.

Figure 9 and Figure 10, which is a cross-sectional view of Figure 9 taken along line 10-10, show an example in which the apexes of the curved portions 24 of a pair of damper units 26A, 26B are joined together with bolts 66 and nuts 68. When joining the apexes of the curved portions 24 of a pair of damper units 26A, 26B together with bolts 66 and nuts 68 in this way, the curved portions 24 may be partially widened to take into account the cross-sectional loss caused by the bolt holes.

In the above embodiment, as shown in FIG. 1, the end 36 of the straight portion 22 of the damper units 26A and 26B is fixed to the base plate 28 provided on the upper surface of the lower column 16 by the bolt 32, and the end 34 of the straight portion 20 of the damper units 26A and 26B is fixed to the base plate 30 provided on the lower surface of the upper column 18 by the bolt 32, so that the damper 10 is provided between the lower column 16 and the upper column 18. However, as shown in the perspective view of FIG. 11, the end 34, 36 of the straight portion 20, 22 of the damper units 26A and 26B may be widened to take into account the cross-sectional loss caused by the bolt holes.

In the above embodiment, as shown in Figures 1 and 2, the curved portions 24 of the damper units 26A and 26B that make up the damper 10 are formed in an arc shape, but the curved portions may have other shapes as long as they are curved. For example, the dampers may be dampers 70, 72, 74, 76, and 78 shown in the elevational views of Figures 12(a) to (e). The curved portions 24 of the damper units 26A and 26B that make up the damper 78 shown in Figure 12(e) are formed in the shape of a quadratic curve.

In the above embodiment, as shown in FIG. 1, the damper units 26A and 26B of the damper 10 are metal members made of steel, but the damper units 26A and 26B may be any metal members having elastic plasticity. For example, the damper units 26A and 26B may be made of an alloy such as an Fe-Mn-Si alloy, an aluminum material, or the like.

In addition, in the above embodiment, as shown in FIG. 1, an example was shown in which the damper 10 was provided between the lower column 16 and the upper column 18 that constitute the partition 102, but the damper 10 may also be installed in the middle of a wall, panel, etc. installed in a column-beam frame that constitutes a vibration-controlled floor of a vibration-controlled building, and function as a vibration-controlled damper.

In the above embodiment, as shown in FIG. 1, the damper 10 is arranged in the vibration-control floor 14 of the building 12, which is a vibration-control building, and functions as a vibration-control damper. However, the damper 10 may be arranged in a base isolation layer, such as a base isolation layer or intermediate isolation layer, of a seismic isolation building and used as a seismic isolation damper. That is, the damper 10 may be provided in a seismic isolation layer formed between a lower structure and an upper structure that move relatively in the horizontal direction by fixing the end 36 of one straight portion 22 of each of the pair of damper units 26A, 26B to the upper surface of the lower structure and fixing the end 34 of the other straight portion 20 of each of the pair of damper units 26A, 26B to the lower surface of the upper structure (see FIG. 1).

Furthermore, in the above embodiment, as shown in FIG. 1, an example was shown in which one damper 10 was placed on the vibration control floor 14 of the building 12, but any number of dampers 10 may be placed, and any arrangement may be used.

The elevation view of FIG. 13 shows an example in which three dampers 10 are installed side by side as vibration dampers in the middle of a stud 90 arranged on a vibration control floor 88 of a building 86. The end of one straight section 22 of the damper units 26A, 26B is fixed to the upper surface of a lower stud 92 that constitutes the stud 90 and is provided on a floor slab 94, and the end of the other straight section 20 of the damper units 26A, 26B is fixed to the lower surface of an upper stud 98 that constitutes the stud 90 and is provided below a beam 96 and is located above the lower stud 92 at a distance from the lower stud 92. In this way, the dampers 10 can be used as vibration dampers provided in the middle of the stud 90.

The plan view of Figure 14 and the plan view of Figure 15 show an example in which two dampers 10 as seismic isolation dampers are arranged opposite each other in the girder direction 82 of the building 80 in a plan view on the seismic isolation layer, and two dampers 10 as seismic isolation dampers are arranged opposite each other in the beam direction 84 of the building 80 in a plan view.

In the above embodiment, as shown in FIG. 1, an example was shown in which the damper 10 was provided between the floor slab 100, which is the lower structure as the first structure, and the beam 104, which is the upper structure as the second structure, both of which are constructed so as to be relatively movable in the horizontal direction. However, the damper 10 may also be provided between the first structure and the second structure which are constructed so as to be relatively movable in the vertical direction or in a diagonal direction relative to the vertical direction.

In addition, in the above embodiment, as shown in FIG. 1, an example was shown in which the damper 10 was applied to a building 12, but the damper 10 can be applied to buildings of various structures, such as reinforced concrete construction, steel-reinforced concrete construction, CFT construction (Concrete Filled Steel Tube construction), and wooden construction.

Although one embodiment of the present invention has been described above, the present invention is not limited to this embodiment, and one embodiment and various modified examples may be used in appropriate combination, and the present invention may of course be embodied in various forms without departing from the spirit of the present invention.

10, 70, 72, 74, 76, 78 Damper 20, 22 Straight section 24 Curved section 26A, 26B Damper unit 34, 36 End 86 Building 88 Vibration control floor 90, 102 Stud 16, 92 Lower pillar 18, 98 Upper pillar

Claims (2)

a pair of metallic damper units each having two straight sections arranged in parallel and a curved section connecting the ends of the two straight sections are arranged in the same plane, and the apexes of the curved sections of the pair of damper units are connected to each other;
A damper in which an end of one of the straight sections of the damper unit is fixed to the upper surface of a lower column that constitutes a partition wall arranged on a vibration-control floor of a building, and an end of the other straight section of the damper unit is fixed to the lower surface of an upper column that constitutes the partition wall and is arranged above the lower column and spaced apart from the lower column. The damper according to claim 1, wherein the curved portion is formed in an arc shape.