JP7762055B2 - Vibration Control System - Google Patents

Description

The present invention relates to a vibration control system that uses a tuned mass damper (TMD) in a roof structure to suppress vertical vibrations of the roof structure.

The background art of the present invention is a technology in which a truss structure such as a roof is provided with a vibration control device that uses a lighting unit provided on the truss structure as a weight member to suppress vibration of the truss structure (see, for example, Patent Document 1).
Furthermore, there is a TMD mechanism for beam strings that is configured to suppress vertical vibration of the beam strings by including an inertial mass damper, which is a dedicated weight part (see, for example, Patent Document 2).

Japanese Utility Model Application Laid-Open Publication No. 01-118501 Patent No. 5316854

The configuration described in Patent Document 1 above uses lighting units as the weights of a vibration control device that suppresses vibrations of truss structures such as roofs, allowing for a more rational design of the vibration control device compared to systems that use dedicated weights. However, because lighting units have a smaller mass than truss structures such as roofs, their effectiveness in suppressing vibrations of the truss structure is reduced. Furthermore, because lighting units are scattered throughout the truss structure, using them as weights of a vibration control device results in them acting only partially on the truss structure, making them less suitable for suppressing vibrations of truss structures. There is room for improvement in effectively suppressing vibrations of truss structures.

In the configuration described in Patent Document 2, the TMD mechanism is equipped with an inertial mass damper that serves as a dedicated weight, which effectively suppresses vibrations in the truss structure. However, there is room for improvement in rationally configuring the TMD mechanism.

In light of this situation, the main objective of this invention is to effectively suppress vertical vibration of the roof frame while rationally configuring the TMD.

A first characteristic configuration of the present invention is a vibration control system that includes a TMD in a roof structure to suppress vertical vibration of the roof structure,
The TMD is configured in a form in which a catwalk supported by the roof frame serves as a weight portion ,
The roof frame has a plurality of truss beams provided as main beams, which extend in a cantilevered manner from the outer edge of the roof frame and are arranged at predetermined intervals in a direction along the outer edge of the roof frame,
The catwalk is formed in a long shape that extends continuously across a plurality of truss beams in the direction of arrangement of the truss beams, and is supported on the extending end side of the truss beams .

According to this configuration, when the roof structure vibrates vertically, the catwalk, which has a relatively large mass and is continuously attached to the roof structure to enable adjustment and inspection of lighting equipment, sound equipment, etc. installed on the roof structure, vibrates vertically as the weight part of the TMD in response to this vertical vibration, thereby absorbing the vertical vibration of the roof structure, thereby effectively suppressing the vertical vibration of the roof structure.
In other words, by using the catwalk, which has a relatively large mass and is continuously attached to the roof structure, as the weight of the TMD, vertical vibration of the roof structure can be effectively suppressed with a rational configuration that does not require a dedicated weight.

A second characteristic feature of the present invention is that the TMD is configured so that the natural frequency of the catwalk is synchronized with the natural frequency of the roof frame by adjusting at least one of the mass and rigidity of the catwalk.

According to this configuration, for example, the natural frequency of the catwalk can be synchronized with the natural frequency of the roof structure by selecting the type and size of steel material to be used for the catwalk and adjusting either or both of the mass and rigidity of the catwalk according to the natural frequency of the roof structure that has been assumed in advance.
As a result, when the roof structure vibrates vertically, the catwalk acts as the weight part of the TMD and vibrates vertically in sync with the vertical vibration of the roof structure, thereby absorbing the vertical vibration of the roof structure more effectively, thereby more effectively suppressing the vertical vibration of the roof structure.
As a result, vertical vibration of the roof frame can be suppressed more rationally and effectively.

A third characteristic feature of the present invention is that the main frame of the catwalk is equipped with a mass adjustment means for adjusting the mass of the catwalk.

According to this configuration, by adjusting the mass of the catwalk using the mass adjusting means, the natural frequency of the catwalk can be easily and accurately tuned to the natural frequency of the roof frame.
As a result, when the roof structure vibrates vertically, the catwalk acts as the weight part of the TMD and vibrates vertically in precise synchronization with the vertical vibration of the roof structure in response to this vertical vibration, thereby more effectively absorbing the vertical vibration of the roof structure and thereby more effectively suppressing the vertical vibration of the roof structure.
As a result, vertical vibration of the roof frame can be suppressed simply and effectively.

A fourth characteristic feature of the present invention is that a damping material is provided between the roof frame and the main frame of the catwalk to damp vertical vibrations of the roof frame .
A fifth characteristic feature of the present invention is that the damping material is bridged between the roof structure and the main frame in an attitude inclined in the extending direction of the catwalk.
A sixth characteristic configuration of the present invention is that the damping material is installed in a V-shape between adjacent truss beams, spanning the upper chord members of the truss beams and the main frame of the catwalk.

With this configuration, the catwalk effectively absorbs vertical vibrations of the roof structure as the weight of the TMD, and the damping material also attenuates the vertical vibrations of the roof structure, allowing for more rapid suppression of vertical vibrations of the roof structure.

A seventh characteristic configuration of the present invention is that the catwalk is supported on the roof frame so as to be vertically movable via a support member that protrudes from the roof frame toward the catwalk so as to be vertically swingable,
The TMD is configured in such a way that the catwalk serves as the weight portion by supporting a position on the support member that is closer to the swing fulcrum than the support position of the catwalk.

According to this configuration, when the roof structure vibrates vertically, the catwalk acts as the weight part of the TMD and moves up and down in response to this vertical vibration along with the up and down swing of the support member, thereby absorbing the vertical vibration of the roof structure, thereby effectively suppressing the vertical vibration of the roof structure.
Furthermore, since the TMD supports a position on the swing fulcrum side that has a smaller amount of vertical movement than the support position of the catwalk on the support member, the vertical size of the TMD can be made smaller than when supporting the support position of the catwalk, which has a larger amount of vertical movement on the support member.
As a result, the TMD, which uses the catwalk provided on the roof structure as its weight, can be rationally arranged in the limited space of the roof structure, while effectively suppressing vertical vibration of the roof structure.

FIG. 1 is a side view of a main part of a configuration of a roof frame equipped with a TMD in a first embodiment; FIG. 1 is a perspective view of a main part showing the configuration of the TMD and the roof frame in the first embodiment. 3 is a cross-sectional view taken along the line III-III in FIG. FIG. 10 is a vertical cross-sectional view of a main part showing the configuration of the TMD and the roof frame in the second embodiment. FIG. 10 is a vertical cross-sectional view of a main part showing the configuration of the TMD and the roof frame in the third embodiment.

First Embodiment
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a vibration damping system according to the present invention will be described below with reference to the drawings as an example of a mode for carrying out the present invention.

As shown in Figures 1 to 3, the vibration control system of the present invention is configured to suppress vertical vibration of a large-scale roof structure 3 installed in a stadium, arena, etc. by providing a TMD (Tuned Mass Damper) 1 to the roof structure 3.

As shown in FIG. 1, the roof structure 3 is a cantilevered steel structure that covers the stands 41 and other structures that are provided on top of a substructure 4 that is installed to surround the field (not shown).
The roof frame 3 is not limited to a cantilever type, but may be, for example, an arch type.

As shown in Figures 1 to 3, the roof frame 3 is provided with multiple truss beams 31 as main girders. Each truss beam 31 is composed of a pair of upper chords 31A and a single lower chord 31B connected by multiple diagonal members 31C. Circular steel pipes are used for the upper chord 31A, the lower chord 31B, and the diagonal members 31C.
The main beams of the roof structure 3 are not limited to the truss beams 31, but may also be, for example, H-shaped steel beams. Each truss beam 31 may be constructed by connecting a single upper chord member and a single lower chord member with multiple diagonal members spanning them, and each of the upper chord member 31A, lower chord member 31B, and diagonal member 31C may be made of materials other than circular steel pipes, such as square steel pipes or H-shaped steel beams.

As shown in Figures 1 to 3, the roof frame 3 includes a plurality of girders 32 (see Figures 2 and 3) that span and connect the plurality of upper chord members 31A, and a plurality of connecting members 33 (see Figure 1) that connect one end of each truss beam 31 to a support column 42 (see Figure 1) provided on the outer periphery of the substructure 4. H-shaped steel is used for each girder 32, and circular steel pipes are used for each connecting member 33.
Note that the beams 32 are not limited to H-shaped steel, but may be made of channel steel, for example. The connecting members 33 are not limited to circular steel pipes, but may be made of square steel pipes, H-shaped steel, or the like.

As shown in Figures 1 to 3, the roof frame 3 is equipped with a catwalk 5, which is used for adjusting and inspecting lighting and sound equipment (not shown) installed on the roof frame 3. As shown in Figures 2 and 3, the catwalk 5 is configured as a sub-beam spanning adjacent truss beams (girders) 31. More specifically, the catwalk 5 includes multiple main frames 51 spanning the lower chords 31B of adjacent truss beams 31, multiple horizontal braces 52 arranged on the floor surface of the catwalk 5, and expanded metal (not shown) that forms the floor surface of the catwalk 5. Each main frame 51 is formed in a ladder shape from a pair of main members 51A whose ends are pin-joined to the lower chords 31B of the truss beams 31, and multiple connecting members 51B that connect the pair of main members 51A.

As shown in Figures 1 to 3, the TMD 1 is configured with a catwalk 5 supported by the roof frame 3 as the weight 11. As mentioned above, the catwalk 5 is provided as the weight 11 of the TMD 1, with both ends of a pair of main members 51A of the ladder-shaped main frame 51 pin-joined to the lower chord 31B of the truss beam 31, making it prone to vibrating in the vertical direction relative to the roof frame 3.

The TMD 1 is configured so that the natural frequency of the catwalk 5 is in tune with the natural frequency of the roof frame 3 by adjusting at least one of the mass and rigidity of the catwalk 5. In the TMD 1 exemplified in this first embodiment, the type and size of steel material used for the catwalk 5 is selected in accordance with the pre-assumed natural frequency of the roof frame 3, and both the mass and rigidity of the catwalk 5 are adjusted, so that the natural frequency of the catwalk 5 is in tune with the natural frequency of the roof frame 3.
However, this configuration is not limiting, and the catwalk 5 may be configured so that its natural frequency is in tune with the natural frequency of the roof structure 3 by adjusting either the mass or rigidity of the catwalk 5.
As for the steel materials used for the catwalk 5, for example, H-shaped steel or channel steel can be used for the main members 51A and connecting members 51B of the main frame 51, and for example, round steel bars or L-shaped steel can be used for the horizontal braces 43. The floor surface of the catwalk 5 is not limited to expanded metal, and for example, perforated steel plates can be used.

As shown in Figures 2 and 3, each main frame 51 of the catwalk 5 is equipped with a mass adjustment means 53 for adjusting the mass of the catwalk 5. The mass adjustment means 53 is provided in the center of the extension direction of each main member 51A of each main frame 51, allowing for highly accurate mass adjustment of the catwalk 5 by attaching and detaching an adjustment mass.

2 and 3, four oil dampers 6 are provided as damping materials between each truss beam 31 of the roof structure 3 and each ladder-shaped main frame 51 of the catwalk 5. The four oil dampers 6 are installed in a V-shape via a pair of round steel bars 7, spanning between each upper chord member 31A of the truss beam 31 and the center of each main member 51A of the main frame 51 in the extension direction.
The damping material is not limited to the oil damper 6, but may be, for example, a viscous damper.

With the above configuration, when the roof frame 3 vibrates vertically, the catwalk 5, which has a relatively large mass and is continuously attached to the roof frame 3 to allow for adjustment and inspection of lighting and sound equipment installed on the roof frame 3, vibrates vertically in sync with the vertical vibration of the roof frame 3 as the weight portion 11 of the TMD 1, absorbing the vertical vibration of the roof frame 3 and effectively suppressing the vertical vibration of the roof frame 3.

In other words, by using the catwalk 5, which is a relatively large mass and is continuously attached to the roof frame 3, as the weight 11 of the TMD 1, vertical vibration of the roof frame 3 can be effectively suppressed with a rational configuration that does not require a dedicated weight.

Furthermore, the main frame 51 of the catwalk 5 is equipped with a mass adjustment means 53 for adjusting the mass of the catwalk 5. As mentioned above, even if it is not possible to precisely tune the natural frequency of the catwalk 5 to the natural frequency of the roof frame 3 by simply selecting the type and size of steel material used for the catwalk 5 and adjusting both the mass and rigidity of the catwalk 5 according to the pre-determined natural frequency of the roof frame 3, by adjusting the mass of the catwalk 5 using the mass adjustment means 53, it is possible to easily and precisely tune the natural frequency of the catwalk 5 to the natural frequency of the roof frame 3. As a result, vertical vibration of the roof frame 3 can be easily and effectively suppressed.

Furthermore, by providing four oil dampers 6 as damping materials between the roof structure 3 and the main frame 51 of the catwalk 5, the catwalk 5 effectively absorbs the vertical vibration of the roof structure 3 as the weight part 11 of the TMD 1. In addition, each oil damper 6 damps the vertical vibration of the roof structure 3, allowing the vertical vibration of the roof structure 3 to be more quickly suppressed.

Second Embodiment
Hereinafter, as an example of a mode for carrying out the present invention, a second embodiment of a vibration control system according to the present invention will be described with reference to the drawings.
Note that the vibration control system illustrated in this second embodiment differs from the vibration control system illustrated in the first embodiment above in the support structure of the catwalk in the roof structure and the configuration of the TMD, and therefore, in the following, only the support structure of the catwalk and the configuration of the TMD will be described.

As shown in Figure 4, the catwalk 5 is provided on the roof structure 3 so as to pass between a pair of upper chord members 31A and lower chord members 31B of each truss beam 31 and between adjacent diagonal members 31C.

The catwalk 5 is supported on the roof frame 3 in a lever-type configuration via multiple support members 8 that protrude from the roof frame 3 toward the catwalk 5 and are free to swing up and down. Each support member 8 is connected to a support column 34 spanning the lower chord 31B of the roof frame 3 and the girder 32 via a fulcrum pin 35 provided parallel to the girder 32, allowing it to swing up and down. The free ends of each support member 8 are connected to the upper ends of each vertical member 55 that extends upward from a pair of main members 51A in the catwalk 5. As a result, each support member 8 is configured to support the catwalk 5 at its free ends. Each support member 8 is set to protrude in the opposite direction to the extension direction of the cantilever roof frame 3. This increases the beam width at the catwalk placement section of each truss beam 31, where the catwalk 5 supported on the free end of each support member 8 is located, compared to when the support members 8 protrude in the same direction as the extension direction of the roof frame 3. This ensures that there is more space available to place the catwalk 5 on the roof frame 3.

TMD1 is configured so that the catwalk 5 serves as a weight 11 by supporting a position on the support member 8 that protrudes vertically from the roof frame 3 and is closer to the swing fulcrum than the support position of the catwalk 5. TMD1 is equipped with an elastic support mechanism 12 that supports a position on the support member 8 that is closer to the swing fulcrum than the support position of the catwalk 5.

The elastic support mechanism 12 includes an upper support member 15 mounted on a pair of upper chords 31A of each truss beam 31, an intermediate support member 16 provided on the support member 8 at a position closer to the swing fulcrum than the support position of the catwalk 5, and a lower support member 17 provided on the lower chord 31B of each truss beam 31. The intermediate support member 16 is rotatable relative to the support member 8 via a support pin 18 provided parallel to the fulcrum pin 35.

The elastic support mechanism 12 includes an upper elastic body 13 provided between the upper support member 15 and intermediate support member 16 of the elastic support section 12 in a pre-compressed state so that it is compressed and elastically deformed when the catwalk 5 is raised, and a lower elastic body 14 provided between the intermediate support member 16 and lower support member 17 of the elastic support section 12 in a pre-compressed state so that it is compressed and elastically deformed when the catwalk 5 is lowered. The upper and lower elastic bodies 13, 14 support the catwalk 5 via support members 8 and the like so that their mutual elasticity allows the catwalk 5 to return to its reference position.

Each elastic body 13, 14 is composed of a pair of coil springs 13A, 14A aligned in the extension direction of the support member 8. The upper end of each coil spring 13A of the upper elastic body 13 is supported by an upper support member 15 having a steel plate extending over its upper end. The lower end of each coil spring 13A of the upper elastic body 13 is supported by an upper end of an intermediate support member 16 having a steel plate extending over its lower end. The upper end of each coil spring 14A of the lower elastic body 14 is supported by a lower end of the intermediate support member 16 having a steel plate extending over its upper end. The lower end of each coil spring 14A of the lower elastic body 14 is supported by a lower support member 17 having a steel plate extending over its lower end.
The upper and lower elastic bodies 13, 14 are not limited to those constituted by a pair of coil springs 13A, 14A, but may be constituted by a single coil spring or a rubber block.

With the above configuration, when the roof frame 3 vibrates vertically, the catwalk 5 acts as the weight portion 11 of the TMD 1, moving up and down along with the up and down swing of the support member 8 in response to this vertical vibration, thereby absorbing the vertical vibration of the roof frame 3, thereby suppressing the vertical vibration of the roof frame 3.

Furthermore, by adjusting the elastic modulus of each elastic body 13, 14 (each pair of coil springs 13A, 14A), the natural frequency of the catwalk 5 can be easily synchronized with the natural frequency of the roof frame 3, thereby more effectively suppressing vertical vibration of the roof frame 3.

When the catwalk 5 rises in response to vertical vibration of the roof frame 3, the rise of the support member 8 accompanying this rise causes the upper elastic body 13 arranged above the support member 8 in the elastic support mechanism 12 supporting the support member 8 to elastically deform, and the lower elastic body 14 arranged below the support member 8 uses its elasticity to maintain a state in which it receives and supports the support member 8 from below. When the catwalk 5 descends in response to vertical vibration of the roof frame 3, the rise of the support member 8 accompanying this rise causes the lower elastic body 14 arranged below the support member 8 in the elastic support mechanism 12 to elastically deform, and the upper elastic body 13 arranged above the support member 8 uses its elasticity to maintain a state in which it receives and supports the support member 8 from above.

In other words, when the catwalk 5 moves up and down in response to vertical vibrations of the roof frame 3, the upper elastic body 13 and lower elastic body 14, which support the catwalk 5 via support members 8 and the like, elastically deform in opposite directions via the support members 8 in response to the up and down movement of the catwalk 5, and their mutual elasticity returns the catwalk 5 to its reference position via the support members 8 and the like.

As a result, when the catwalk 5 moves up and down in response to vertical vibrations of the roof frame 3, the upper elastic body 13 and the lower elastic body 14 stably support the catwalk 5 and return the catwalk 5 to its reference position while efficiently damping the up and down movement of the catwalk 5 in response to vertical vibrations of the roof frame 3. This allows the vertical vibrations of the roof frame 3 to be damped along with the up and down movement of the catwalk 5, and the vertical vibrations of the roof frame 3 to be quickly suppressed.

Furthermore, in TMD1, the position on the swing fulcrum side, which has a smaller amount of vertical movement than the support position of the catwalk 5 on the support member 8, is supported by the elastic support mechanism 12, so the vertical size of TMD1 can be reduced compared to when supporting the support position of the catwalk 5, which has a larger amount of vertical movement on the support member 8.

Furthermore, as mentioned above, by setting the protruding direction of each support member 8 in the opposite direction to the extension direction of the cantilever-type roof frame 3, a large space can be secured for the catwalk 5 on the roof frame 3. Furthermore, since the up and down movement of the catwalk 5 is limited by the upper and lower elastic bodies 13, 14 of the elastic support mechanism 12, even if a TMD 1 with the catwalk 5 as the weight part 11 is installed in the limited space of the roof frame 3, the up and down movement of the catwalk 5 can be prevented from interfering with the truss beams 31, etc.

Furthermore, because the elastic support mechanism 12 supports the swing fulcrum side of the support member 8, even if the load acting on the upper and lower elastic bodies 13, 14 provided in the elastic support mechanism 12 increases, the upper and lower elastic bodies 13, 14 are composed of a pair of coil springs 13A, 14A aligned in the extension direction of the support member 8, so the load acting on each elastic body 13, 14 is distributed to the pair of coil springs 13A, 14A, reducing the load borne by each coil spring 13A, 14A, thereby enabling the swing fulcrum side of the support member 8 to be supported appropriately.

Furthermore, the support members 8 supporting the catwalk 5 and the elastic support mechanisms 12 supporting these support members 8 are provided in the inverted triangular internal space formed by a pair of upper chord members 31A and a single lower chord member 31B in each truss beam 31. This improves the appearance when looking up at the roof frame 3 from a stand 41, etc., compared to when the support members 8 and elastic support mechanisms 12 are exposed to the outside of each truss beam 31.

In other words, the TMD 1, which uses the catwalk 5 provided on the roof frame 3 as the weight part 11, can be arranged in a rational and aesthetically pleasing manner within the limited space of the roof frame 3, while effectively and quickly suppressing vertical vibration of the roof frame 3.

In the second embodiment, the upper ends of the upper coil springs 13A provided in the elastic support mechanism 12 are supported by upper support members 15 spanning a pair of upper chord members 31A of each truss beam 31, and the lower ends of the lower coil springs 14A are supported by lower support members 17 provided on the lower chord members 31B of each truss beam 31. However, this is not limiting. For example, each truss beam 31 may be provided with an inverted triangular support truss spanning each pair of upper chord members 31A and lower chord members 31B, with the upper spring supports provided at the top of this support truss supporting and supporting the upper ends of the upper coil springs 13A, and the lower spring supports provided at the bottom of the support truss supporting and supporting the lower ends of the lower coil springs 14A.

Third Embodiment
Hereinafter, as an example of a mode for carrying out the present invention, a third embodiment of a vibration control system according to the present invention will be described with reference to the drawings.
It should be noted that the vibration control system illustrated in this third embodiment differs from the vibration control system illustrated in the second embodiment above in the configuration of the elastic support mechanism, and therefore only the configuration of the elastic support mechanism will be described below.

As shown in Figure 5, the TMD 1 is equipped with an elastic support mechanism 22 that supports a position on the support member 8 closer to the swing fulcrum than the support position of the catwalk 5.

The elastic support mechanism 22 is equipped with an elastic body 23 that elastically deforms in response to the compressive force caused by the vertical movement of the catwalk 5 from its reference position. The elastic body 23 is composed of a pair of coil springs 23A aligned in the extension direction of the support member 8. Each coil spring 23A is supported by a spring support 24 provided at a position on the support member 8 closer to the swing fulcrum than the support position for the catwalk 5.

The spring support 24 comprises a vertical member 24B rotatably mounted on the support member 8 via a support pin 24A arranged parallel to the fulcrum pin 35; upper and lower spring receiving members 24C and 24D movable vertically relative to the vertical member 24B; an upper stopper 24E fixed to the upper end of the vertical member 24B and receiving the upper spring receiving member 24C at its upper limit; and a lower stopper 24F fixed to the lower side of the vertical member 24B and receiving the lower spring receiving member 24D at its lower limit. The spring support 24 receives and supports the upper end of each coil spring 23A with the upper spring receiving member 24C, and the upper end of each coil spring 23A with the lower spring receiving member 24D.

The upper and lower ends of each coil spring 23A are supported by spring supports 25 provided between the catwalk 5 and support column 34 of each truss beam 31, via upper and lower spring support members 24C, 24D of the spring support 24. The spring supports 25 are provided across a pair of upper chord members 31A of each truss beam 31. The spring supports 25 are provided with upper spring support portions 25A that support the upper ends of each coil spring 23A when the catwalk 5 moves up and down above the reference position, and lower spring support portions 25B that support the lower ends of each coil spring 23A when the catwalk 5 moves up and down below the reference position.

With the above configuration, when the roof frame 3 vibrates vertically, the catwalk 5 acts as the weight portion 11 of the TMD 1, moving up and down along with the up and down swing of the support member 8 in response to this vertical vibration, thereby absorbing the vertical vibration of the roof frame 3, thereby suppressing the vertical vibration of the roof frame 3.

Furthermore, by adjusting the elastic modulus of the elastic body 23 (pair of coil springs 23A), the natural frequency of the catwalk 5 can be easily synchronized with the natural frequency of the roof frame 3, thereby more effectively suppressing vertical vibration of the roof frame 3.

When the catwalk 5 rises from the reference position in response to vertical vibration of the roof structure 3, the vertical member 24B of the spring support 24 rises together with the support member 8, pushing up the lower spring support member 24D via the lower stopper 24F fixed to its lower side, causing the elastic body 23 (a pair of coil springs 23A) to elastically deform with its upper end supported by the upper spring support portion 25A of the spring support body 25 via the upper spring support member 24C. Furthermore, when the catwalk 5 descends from the reference position in response to vertical vibration of the roof frame 3, the vertical member 24B of the spring support 24 descends along with the support member 8, pulling down the upper spring receiving member 24C via the upper stopper 24E fixed to its upper end. This causes the elastic body 23 (pair of coil springs 23A) to elastically deform with its lower end received by the lower spring receiving portion 25B of the spring receiving body 25 via the lower spring receiving member 24D. This elastic deformation of the elastic body 23 (pair of coil springs 23A) damps the vertical vibration of the roof frame 3 as the catwalk 5 moves up and down, allowing the vertical vibration of the roof frame 3 to be quickly suppressed.

In other words, the vibration control system illustrated in the third embodiment provides the same operational effects as the vibration control system illustrated in the second embodiment, and because the single elastic body 23 provided in the elastic support mechanism 22 accommodates up and down movement on both the upper and lower sides of the reference position of the catwalk 5, it is possible to simplify the configuration of the elastic support mechanism 22 by reducing the number of elastic bodies 23 provided, compared to, for example, a case in which upper and lower elastic bodies are provided that individually accommodate up and down movement above and below the reference position.

[Another embodiment]
Another embodiment of the present invention will now be described.
The configurations of the other embodiments described below are not limited to being applied alone, but can also be applied in combination with the configurations of the above-described embodiment or other other embodiments.

(1) In the first embodiment described above, the catwalk 5 used for the weight portion 11 of the TMD 1 is exemplified as a sub-beam type structure spanning adjacent truss beams (girders) 31, and in the second and third embodiments described above, as a lever type structure supported on the roof frame 3 via support members 8 so as to be able to move up and down freely. However, this is not limited to these, and the catwalk 5 may also be configured as a suspended type structure suspended from each truss beam (girder) 31, for example.

(2) In the above embodiments, examples of vibration control systems have been given in which a single row of catwalks 5 provided on the roof frame 3 is configured as the weight portion 11 of the TMD 1. However, the present invention is not limited to these examples, and may also be configured, for example, in which two rows of catwalks 5 provided on the roof frame 3 are configured as the weight portion 11 of the TMD 1.

1 TMD
3 Roof frame 5 Catwalk 6 Damping material 8 Support member 11 Weight portion 51 Main frame 53 Mass adjustment means

Claims (7)

A vibration control system that includes a TMD in a roof structure to suppress vertical vibration of the roof structure,
The TMD is configured in a form in which a catwalk supported by the roof frame serves as a weight portion ,
The roof frame has a plurality of truss beams provided as main beams, which extend in a cantilevered manner from the outer edge of the roof frame and are arranged at predetermined intervals in a direction along the outer edge of the roof frame,
The catwalk is a vibration control system that is supported on the extended end side of the truss beams in a long form that extends continuously across multiple truss beams in the arrangement direction of the truss beams . The vibration control system described in claim 1, wherein the TMD is configured to synchronize the natural frequency of the catwalk with the natural frequency of the roof structure by adjusting at least one of the mass and stiffness of the catwalk. A vibration control system as described in claim 1 or 2, wherein the main frame of the catwalk is provided with a mass adjustment means for adjusting the mass of the catwalk. A vibration control system according to any one of claims 1 to 3, wherein a damping material is provided between the roof structure and the main frame of the catwalk to damp vertical vibrations of the roof structure . 5. The vibration control system according to claim 4, wherein the damping material is bridged between the roof structure and the main frame in an inclined position in the extending direction of the catwalk. The vibration control system according to claim 4, wherein the damping material is installed in a V-shape between the adjacent truss beams, spanning the upper chord members of the truss beams and the main frame of the catwalk. The catwalk is supported on the roof frame so as to be vertically movable via a support member that protrudes from the roof frame toward the catwalk so as to be vertically swingable,
A vibration control system described in any one of claims 1 to 6 , wherein the TMD is configured in a form in which the catwalk serves as the weight by supporting a position on the support member that is closer to the swing fulcrum than the support position of the catwalk.