Vibration control device for architectural structure

Abstract

To provide a vibration control device for an architectural structure having a novel structure that can effectively reduce vibration of an architectural structure sensed by a person.SOLUTION: A vibration control device 10 for an architectural structure constitutes an auxiliary vibration system with an architectural structure 12 as a main vibration system by elastically supporting a mass member 16 with a spring member 20 against the architectural structure 12, where the auxiliary vibration system is composed of a plurality of divided auxiliary vibration systems 36 tuned to mutually different natural frequencies, and the natural frequencies of the plurality of divided auxiliary vibration systems 36 are set to be spaced apart in a geometric progression with a constant ratio.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a vibration damping device for architectural structures that constitutes a secondary vibration system for an architectural structure such as a house, which is a main vibration system, and suppresses vibration of the architectural structure. [Background technology]

[0002] Conventionally, building structures such as ordinary houses may experience vibrations due to external forces such as traffic vibrations, wind, and people moving on the floor, and in such cases, people inside the building structure may find the vibrations unpleasant.

[0003] Therefore, the applicant has proposed a vibration control device for architectural structures, for example, in JP 2007-046450 A (Patent Document 1). The vibration control device for architectural structures is provided with a plurality of divided sub-vibration systems that constitute a sub-vibration system, and the natural frequencies of these divided sub-vibration systems are set to be different from each other. In this way, if the sub-vibration system for an architectural structure is composed of a plurality of divided sub-vibration systems with different natural frequencies, it becomes possible to obtain a stable vibration control effect even if the natural frequency of the architectural structure changes slightly due to, for example, a change in the environment. In addition, the same sub-vibration system can be adopted for similar houses that have slightly different natural frequencies, making it possible to improve efficiency. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2007-046450 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, how people perceive shaking (vibration) varies depending on the frequency of the vibration, and there are frequency ranges in which people are sensitive to vibration and frequency ranges in which people are not sensitive to vibration. Therefore, simply reducing the mechanical vibration energy intensity can easily cause problems in frequency ranges in which people are sensitive to vibration, while in frequency ranges in which people are not sensitive to vibration, vibration is unlikely to be a problem even if the mechanical vibration energy intensity is relatively large.

[0006] However, conventional vibration control devices have only aimed to reduce mechanical vibration energy without taking such human sensations into consideration. Therefore, there is still room for improvement as a vibration control device for building structures that reduces discomfort and improves the comfort of life not for vibration levels that would cause structural collapse, but for vibration levels that are likely to cause problems in daily life, such as the vibration of an ordinary house built next to a road.

[0007] An object of the present invention is to provide a vibration damping device for architectural structures having a novel structure that can effectively reduce the vibrations of architectural structures that are felt by people.

[0008] Another object of the present invention is to provide a novel tuning method for a vibration damping device for architectural structures, which can effectively reduce vibrations felt by people. [Means for solving the problem]

[0009] The following describes preferred embodiments for understanding the present invention, but the embodiments described below are merely illustrative and may be combined with one another as appropriate, and the multiple components described in each embodiment may be recognized and used independently as far as possible, and may also be combined with any of the components described in another embodiment as appropriate. As a result, the present invention is not limited to the embodiments described below, and various other embodiments may be realized.

[0010] The first aspect is a vibration control device for architectural structures that forms a secondary vibration system with the architectural structure as the main vibration system by elastically supporting a mass member with a spring member against the architectural structure, and the secondary vibration system is composed of a plurality of divided sub-vibration systems tuned to mutually different natural frequencies, and the natural frequencies of the plurality of divided sub-vibration systems are set to be spaced apart in a geometric progression at a constant ratio.

[0011] When an effective vibration control action against vibrations over a certain frequency range is to be obtained by a vibration control device having a plurality of divided sub-vibration systems, since vibrations in the low frequency range are more easily felt by people than those in the high frequency range, a higher vibration control performance is required in the low frequency range than in the high frequency range. Therefore, in the vibration control device for architectural structures constructed according to this embodiment, the natural frequencies (tuning frequencies) of the plurality of divided sub-vibration systems are set at intervals in a geometric progression of a certain ratio, and the intervals between the tuning frequencies of the plurality of divided sub-vibration systems become narrower as the frequency decreases. Therefore, the vibration control action of more divided sub-vibration systems contributes to low-frequency vibrations than to high-frequency vibrations, and a better vibration control effect is achieved. As a result, low-frequency vibrations that the human body is sensitive to can be efficiently suppressed with a relatively small number of divided sub-vibration systems, and the vibration state that people in the architectural structure actually feel can be effectively improved.

[0012] When the natural frequencies of the multiple divided sub-vibration systems are set at intervals of a fixed ratio in a geometric progression, the number of divided sub-vibration systems that contribute to vibration control in the high frequency range is smaller than when the natural frequencies are set at intervals in an arithmetic progression, and the vibration control effect is relatively small. However, since humans are less sensitive to high frequency vibrations than to low frequency vibrations, the vibration control effect for high frequency vibrations is not as strong as that for low frequency vibrations, and sufficient vibration control performance for high frequency vibrations can be obtained. In particular, high frequency vibrations in architectural structures often have smaller amplitudes and are input broadly over a wider band than low frequency vibrations, so the required vibration control performance is relatively low and even if the intervals between the natural frequencies of the divided sub-vibration systems are wide, the multiple divided sub-vibration systems can contribute to the vibration control of the input vibration.

[0013] In a second aspect, in the vibration damping device for architectural structures according to the first aspect, the intervals between the natural frequencies of the plurality of divided sub-vibration systems are set to a 1 / N octave band.

[0014] According to the vibration damping device for architectural structures constructed according to this embodiment, the natural frequencies of the multiple divided sub-vibration systems are set at intervals that correspond more closely to human sensitivity to vibration, and the vibration state of the architectural structure as sensed by humans can be further improved. In particular, if N is set to a small value such as 3, a vibration damping effect can be obtained over a wider frequency range with fewer divided sub-vibration systems. On the other hand, if N is set to a larger value such as 6 or 12, a higher degree of improvement in the vibration state can be achieved in a relatively narrow frequency range.

[0015] In a third aspect, in the vibration control device for architectural structures described in the first or second aspect, the representative natural frequency of the multiple divided sub-vibration systems is either the arithmetic average value of the minimum and maximum natural frequencies of the multiple divided sub-vibration systems, the arithmetic average value of the natural frequencies of the multiple divided sub-vibration systems, the median value of the natural frequencies of the multiple divided sub-vibration systems, or the natural frequency of the divided sub-vibration system that is closest to either the arithmetic average value or the median value of the natural frequencies of the multiple divided sub-vibration systems, and the difference between the representative natural frequency of the multiple divided sub-vibration systems and the natural frequency of the main vibration system is 40% or less of the natural frequency of the main vibration system.

[0016] According to the vibration control device for architectural structures constructed according to this embodiment, the magnitudes and intervals of the natural frequencies of the divided sub-systems are set so that the representative natural frequency, which is an intermediate value of each of the natural frequencies of the multiple divided sub-systems, is close to the natural frequency of the main vibration system, so that the multiple divided sub-systems exert a vibration control effect when vibration of the natural frequency of the main vibration system is input, and an excellent vibration control effect can be obtained even for vibrations in a lower frequency range than the natural frequency of the main vibration system. In particular, since the difference between the representative natural frequency and the natural frequency of the main vibration system is set to 40% or less of the natural frequency of the main vibration system, the deviation between the representative natural frequency and the natural frequency of the main vibration system is sufficiently small, and the vibration control performance of the vibration control device for architectural structures is effectively exerted on the architectural structure.

[0017] A fourth aspect is a vibration control device for architectural structures described in any one of the first to third aspects, wherein the difference between the natural frequency of one of the multiple divided sub-vibration systems and the natural frequency of the main vibration system is smaller than half the difference between the natural frequency of the divided sub-vibration system that is closest to the natural frequency of the main vibration system on the high frequency side and the natural frequency of the divided sub-vibration system that is closest to the natural frequency of the main vibration system on the low frequency side.

[0018] In the vibration control device for architectural structures constructed according to this embodiment, the divided sub vibration systems, which are tuned to the natural frequency closest to the natural frequency of the main vibration system on the high or low frequency side, exert an effective vibration control effect at the natural frequency of the main vibration system. Therefore, the vibration state is effectively improved in the band near the natural frequency of the main vibration system, where the vibration state is likely to deteriorate.

[0019] A fifth aspect is a vibration control device for architectural structures described in any one of the first to fourth aspects, wherein more than half of the multiple divided secondary vibration systems have a natural frequency that is lower than the natural frequency of the main vibration system.

[0020] According to the vibration damping device for architectural structures constructed according to this embodiment, the natural frequencies of at least half of the divided sub-vibration systems are tuned to a lower frequency side than the natural frequency of the main vibration system, thereby achieving a superior vibration damping effect against vibrations in the low frequency range to which humans are highly sensitive. In particular, since the natural frequencies of the multiple divided sub-vibration systems are spaced at intervals in a geometric progression, for example, by tuning the natural frequencies of the divided sub-vibration systems so that the representative natural frequency shown in the third embodiment is close to the natural frequency of the main vibration system, the natural frequencies of at least half of the divided sub-vibration systems can be easily set to a lower frequency than the natural frequency of the main vibration system.

[0021] The sixth aspect is a tuning method for a vibration control device for an architectural structure, in which a sub-vibration system provided in an architectural structure as a main vibration system is composed of a plurality of divided sub-vibration systems, and the divided sub-vibration systems are tuned to have mutually different natural frequencies, and the natural frequencies of the plurality of divided sub-vibration systems are tuned to be spaced apart in a geometric progression with a constant ratio.

[0022] With a vibration control device for architectural structures constructed in accordance with this embodiment, it is possible to easily obtain a vibration control device for architectural structures that exhibits better vibration control performance for low-frequency vibrations, to which people are highly sensitive, than for high-frequency vibrations, to which people are less sensitive, and that can effectively improve the vibration conditions felt by people. Effect of the Invention

[0023] According to the present invention, the vibration of a building structure felt by people can be effectively reduced by the vibration damping device for building structures. [Brief description of the drawings]

[0024] [Figure 1] FIG. 1 is a diagram showing a vibration damping device for architectural structures according to a first embodiment of the present invention, installed in a house. [Diagram 2] Plan view of the vibration damping device for architectural structures shown in Figure 1 [Diagram 3] Front view of the vibration damping device for architectural structures shown in FIG. [Figure 4]FIG. 2 is a right side view of the vibration damping device for architectural structures shown in FIG. 1, illustrating how the vibration damping device is installed in a house. [Diagram 5] Graph showing vibration damping characteristics of the vibration damping device for architectural structures shown in FIG. [Figure 6] Simulation results of vibration control performance when the representative natural frequency of a vibration control device for architectural structures differs from the natural frequency of the architectural structure [Figure 7] A graph showing an example of the vibration characteristics of a typical house and the tuning of multiple divided sub-vibration systems applied thereto. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0026] In Fig. 1, a vibration damping device for architectural structures (hereinafter referred to as a vibration damping device) 10 constructed according to the present invention is shown in a state where it is installed in a three-story house 12, which is an architectural structure. The vibration damping device 10 is arranged in an attic 14 on the third floor of the house 12 and attached to beams and the like that constitute the ceiling of the third floor of the house 12, forming a secondary vibration system with the house 12 as the primary vibration system. As shown in Figs. 2 to 4, the vibration damping device 10 has a structure in which a mass member 16 and a base member 18 are elastically connected by a rubber mount 20 that serves as a spring member. In the following description, the vertical direction basically refers to the vertical direction in Fig. 1, which is the height direction.

[0027] The mass member 16 is made of a material with a high specific gravity, such as an iron-based metal. The shape of the mass member 16 is not limited, but in this embodiment, it is in the shape of a substantially rectangular block or a thick rectangular flat plate. In this embodiment, as shown in Fig. 2, four mass members 16, 16, 16, 16 are arranged apart from each other vertically and horizontally so that the mass members 16 do not interfere with each other when the mass members 16 are displaced when vibration is input, which will be described later.

[0028] The base member 18 is formed of a steel material and has a rectangular frame portion 22. The rectangular frame portion 22 is composed of a pair of first beams 24a, 24a extending in parallel to each other in the left-right direction (left-right direction in FIG. 2), and four second beams 24b, 24b, 24b, 24b extending in parallel to each other in the front-rear direction (up-down direction in FIG. 2) and connecting the pair of first beams 24a, 24a to each other. In this embodiment, the first and second beams 24a, 24b having a substantially Z-shaped cross-sectional shape are illustrated as an example, but the specific shapes of the first and second beams 24a, 24b are not particularly limited, and shaped materials having various cross-sectional shapes such as an H-shape or a box shape can be used as the first and second beams 24a, 24b.

[0029] Four mass members 16, 16, 16, 16 are attached to the base member 18 (see FIG. 2). Each mass member 16 has its square portion elastically supported by four rubber mounts 20, 20, 20, 20. The rubber mounts 20 are not particularly limited in structure, but in this embodiment, as shown in FIG. 3, have a structure in which a plurality of plate members 28 stacked at a predetermined interval are elastically connected to each other by a rubber elastic body 30. The plate member 28 is a long rectangular plate, and may be a flat plate. For example, both end portions in the longitudinal direction are inclined upward toward the outside in the longitudinal direction, and the rubber elastic body 30 is fixed to each inclined portion. This allows the shared support load of the mass member 16 to be received as a compressive force, and the difference in spring characteristics between the longitudinal direction and the lateral direction of the plate member 28 can be increased, and the resonance frequency of the mass-spring resonance system can be adjusted with a greater degree of freedom by adjusting the orientation of the rubber mounts 20. Through holes are formed in the portions of the plate members 28 where the rubber elastic bodies 30 are fixed, and the rubber elastic bodies 30 disposed between the plate members 28 are integrally continuous. For ease of viewing, in Fig. 3, the plate members covered with the covering rubber are given the reference numeral 28.

[0030] The rubber mount 20 is interposed between the mass member 16 and the base member 18 by a first attachment member 32 arranged at the upper end being fixed to the mass member 16 and a second attachment member 34 arranged at the lower end being fixed to the base member 18. In this way, the mass member 16 is supported by the base member 18 via the rubber mount 20, and a divided secondary vibration system 36 is formed.

[0031] Four mass members 16, 16, 16, 16 are attached to the base member 18 by four rubber mounts 20, 20, 20, 20, and four divided sub-vibration systems 36, 36, 36, 36 are provided on the base member 18. In this way, the vibration damping device 10 including the four divided sub-vibration systems 36, 36, 36, 36 is configured.

[0032] The four divided sub-vibration systems 36, 36, 36, 36 constituting the vibration damping device 10 are set with different natural frequencies (tuning frequencies). The four divided sub-vibration systems 36, 36, 36, 36 are set with geometric progression natural frequencies that change at a constant ratio (common ratio) α. In short, the four divided sub-vibration systems 36, 36, 36, 36 are set so that their natural frequencies are at constant ratio intervals. In the following description, the four divided sub-vibration systems 36, 36, 36, 36 are referred to as divided sub-vibration system 36a, divided sub-vibration system 36b, divided sub-vibration system 36c, and divided sub-vibration system 36d, in order from the side with the lowest natural frequency.

[0033] That is, the natural frequency f2 of the divided sub-vibration system 36b is set to α times the natural frequency f1 of the divided sub-vibration system 36a, which is a positive constant greater than 1. Similarly, the natural frequency f3 of the divided sub-vibration system 36c is set to α times the natural frequency f2 of the divided sub-vibration system 36b, and the natural frequency f4 of the divided sub-vibration system 36d is set to α times the natural frequency f3 of the divided sub-vibration system 36c.

[0034] Preferably, the natural frequency f2 of the divided sub-vibration system 36b is 1 / N octave times the natural frequency f1 of the divided sub-vibration system 36a. Similarly, the natural frequency f3 of the divided sub-vibration system 36c is 1 / N octave times the natural frequency f2 of the divided sub-vibration system 36b, and the natural frequency f4 of the divided sub-vibration system 36d is 1 / N octave times the natural frequency f3 of the divided sub-vibration system 36c. In short, the natural frequencies of the four divided sub-vibration systems 36a, 36b, 36c, and 36d are set at intervals in a geometric progression with a common ratio α of 1 / N octave. In other words, the intervals between the natural frequencies of the four divided sub-vibration systems 36a, 36b, 36c, and 36d are set to be 1 / N octave bands. In this case, the common ratio α of the natural frequencies of the four divided sub-systems 36a, 36b, 36c, and 36d is (10 3 / 10 ) 1 / N It can be calculated as follows:

[0035] When the natural frequencies of the four divided sub-vibration systems 36a, 36b, 36c, and 36d are set at intervals of 1 / N octave band, N is not particularly limited as long as it is an integer of 1 or more, but the smaller the value of N, the wider the intervals of the natural frequencies of the four divided sub-vibration systems 36a, 36b, 36c, and 36d become, and the vibration damping effect can be exerted in a wider frequency range, while the larger the value of N, the narrower the intervals of the natural frequencies of the four divided sub-vibration systems 36a, 36b, 36c, and 36d become, and the higher vibration damping effect can be exerted in a narrower frequency range. The value of N is preferably any one of 1, 3, 6, and 12, and for example, the natural frequencies of the four divided sub-vibration systems 36a, 36b, 36c, and 36d are set at 1 / 3 octave band intervals of N=3.

[0036] In this embodiment, the arithmetic average value ((f1+f2+f3+f4) / 4) of the natural frequencies of all the divided sub-vibration systems 36a, 36b, 36c, 36d is set as the representative natural frequency fm of the four divided sub-vibration systems 36a, 36b, 36c, 36d. The natural frequencies of the divided sub-vibration systems 36a, 36b, 36c, 36d are set so that the difference between the natural frequency F of the house 12 constituting the main vibration system and the representative natural frequency fm is 40% or less (|F-fm|≦0.4F) of the natural frequency F of the house 12. In this embodiment, the representative natural frequency fm of the four divided sub-vibration systems 36a, 36b, 36c, 36d is set so as to be approximately equal to the natural frequency F of the house 12.

[0037] The natural frequency f2 of the divided sub-vibration system 36b is closest on the low frequency side to the natural frequency F of the house 12, and the natural frequency f3 of the divided sub-vibration system 36c is closest on the high frequency side to the natural frequency F of the house 12. Therefore, half of the four divided sub-vibration systems 36a, 36b, 36c, and 36d have natural frequencies tuned to a lower frequency than the natural frequency F of the house 12.

[0038] In addition, the difference between the natural frequency F and the natural frequency f3 of the house 12 is set to be smaller than half the difference between the natural frequency f2 and the natural frequency f3 (f3-F<(f3-f2) / 2). In other words, the divided sub-vibration system 36c is set to a natural frequency closer to the natural frequency F of the house 12 than the other divided sub-vibration systems 36a, 36b, and 36d. In this embodiment, the natural frequency f3 of the divided sub-vibration system 36c is different from the natural frequency F of the house 12, but the natural frequencies f3 and F may be the same. Note that when the natural frequency f3 of the divided sub-vibration system 36c is the same as the natural frequency F of the house 12, the difference between the natural frequency F and the natural frequency f3 of the house 12 is 0, so that the difference is smaller than half the difference between the natural frequency f2 and the natural frequency f3. In this way, when the natural frequency of one of the multiple divided sub-vibration systems 36 coincides with the natural frequency F of the house 12, the natural frequency of the divided sub-vibration system 36 can be regarded as the natural frequency that is closest on the high frequency side to the natural frequency F of the house 12.

[0039] The natural frequencies of the four divided sub-vibration systems 36a, 36b, 36c, and 36d can be tuned, for example, by adjusting the mass of the mass member 16 and the spring constant of the rubber mount 20. Also, the natural frequencies of the four divided sub-vibration systems 36a, 36b, 36c, and 36d can be tuned, for example, by adjusting the orientation of each rubber mount 20.

[0040] According to the vibration damping device 10 having the structure of this embodiment, the intervals between the natural frequencies of the four divided sub-vibration systems 36a, 36b, 36c, and 36d are set to have a constant ratio of a geometric progression, so that the intervals between the natural frequencies of the divided sub-vibration systems 36a, 36b, 36c, and 36d are set to be narrower in the low frequency range than in the high frequency range. Therefore, in the vibration damping device 10, the vibration damping action of the divided sub-vibration systems 36 contributes more to vibration input in the low frequency range than vibration input in the high frequency range, and as shown in Fig. 5, the vibration damping device 10 exhibits superior vibration damping performance in the low frequency range. Therefore, according to the vibration damping device 10, it is possible to effectively suppress vibrations in the low frequency range that people are sensitive to, and advantageously improve the vibration state felt by people. In Fig. 5, the intervals between the natural frequencies of the four divided sub-vibration systems 36a, 36b, 36c, and 36d are set to 1 / 6 octave bands, with f1 set to 3 Hz, f2 set to 3.37 Hz, f3 set to 3.78 Hz, and f4 set to 4.24 Hz. The input direction of vibration to the vibration damping device 10 is not particularly limited, and may be horizontal, vertical, or an oblique direction inclined relative to both the horizontal and vertical directions. The vibration direction of the natural frequency tuned in each divided sub-vibration system is set according to the vibration input direction to be damped in the house.

[0041] It is also known that the lower the frequency of the vibration, the narrower the frequency band and the steeper the input, and the higher the frequency of the vibration, the broader the waveform, with a wider frequency band and a smaller input. Therefore, if the natural frequencies of a plurality of divided sub-vibration systems are tuned at equal intervals, the number of divided sub-vibration systems that contribute to low-frequency vibration with a steep waveform may be small, and sufficient vibration damping effect may not be achieved, while the number of divided sub-vibration systems that contribute to high-frequency vibration with a gentle waveform may be large, and excessive vibration damping performance may result. In contrast, in the vibration damping device 10 of this embodiment, the intervals between the natural frequencies of the four divided sub-vibration systems 36a, 36b, 36c, and 36d are set to fixed ratio intervals that become narrower as the frequency decreases, so that a relatively large number of divided sub-vibration systems 36 contribute to vibration damping for low-frequency vibrations with steep waveforms, thereby providing a sufficient vibration damping effect, and a sufficient number of divided sub-vibration systems 36 contribute to vibration damping for high-frequency vibrations with gentle waveforms, even if the intervals between the natural frequencies of the divided sub-vibration systems 36 are wide, thereby providing an effective vibration damping effect. In this way, with the vibration damping device 10 in which the natural frequencies of the four divided sub-vibration systems 36a, 36b, 36c, and 36d are set to fixed ratio intervals, the vibration state experienced by a person can be efficiently improved with a small number of divided sub-vibration systems 36.

[0042] In addition, since the intervals between the natural frequencies of the four divided sub-vibration systems 36a, 36b, 36c, and 36d are set to a constant ratio, the natural frequencies can be easily set compared to when they are set individually according to the vibration damping target, and the vibration damping device 10 can be easily manufactured. That is, if the intervals between the natural frequencies of the four divided sub-vibration systems 36a, 36b, 36c, and 36d are set each time according to the vibration state of the vibration damping target, the work of tuning so that the intervals on the low frequency side become narrower is time-consuming, making mass production difficult and increasing costs and other problems likely to become problems. Therefore, in the vibration damping device 10, the intervals between the natural frequencies of the four divided sub-vibration systems 36a, 36b, 36c, and 36d are set at a constant ratio, so that tuning so that the intervals on the low frequency side become narrower can be easily performed, making mass production easy and realizing cost reduction. Moreover, for example, when constructing the vibration damping device 10 by selecting from a plurality of types of prefabricated divided sub-vibration systems 36, the number of combinations of the divided sub-vibration systems 36 does not become excessively large, making the selection easy.

[0043] Since the natural frequencies of the four divided sub-vibration systems 36a, 36b, 36c, and 36d are set at intervals of 1 / N octave band, it is possible to provide vibration control performance that is more in line with human sensations of vibration. In addition, by appropriately setting the value of N, it is possible to achieve an effective vibration control effect over a wide frequency range, or a high vibration control effect in a narrow frequency range.

[0044] Incidentally, it has been confirmed by simulation that the vibration control device 10, in which the natural frequencies of the four divided sub-systems 36a, 36b, 36c, and 36d are set at fixed ratio intervals, exerts an effective vibration control effect even when the representative natural frequency fm deviates from the natural frequency F of the house 12, as shown in FIG. 6. That is, according to the analysis results shown in FIG. 6, even when the natural frequency F of the house 12 deviates 40% toward the low frequency side from the representative natural frequency fm, it is found that a vibration reduction effect of about 22% is exerted compared to the case without the vibration control device. Also, even when the natural frequency F of the house 12 deviates 40% toward the high frequency side from the representative natural frequency fm, it is found that a vibration reduction effect of about 17% is exerted compared to the case without the vibration control device. Note that, preferably, a sufficient vibration reduction effect of 40% or more can be obtained by setting the deviation of the representative natural frequency fm from the natural frequency F of the house 12 within a range of ±20%.

[0045] The vibration acting on the vibration control device 10 has a steeper waveform with a narrower frequency band and larger input as the natural frequency of the house 12 is lower, and a broader waveform with a wider frequency band and smaller input as the natural frequency of the house 12 is higher. Therefore, in the vibration control device 10 in which the natural frequencies of the four divided sub-vibration systems 36a, 36b, 36c, 36d become narrower as the frequency decreases, when the natural frequency F of the house 12 is shifted toward the lower frequency side with respect to the representative natural frequency fm, the divided sub-vibration systems 36a, 36b on the lower frequency side, which are set at narrow frequency intervals, both contribute to vibration control against the vibration of the natural frequency F, and sufficient vibration control performance can be expected. On the other hand, when the natural frequency F of the house 12 is shifted to the high frequency side with respect to the representative natural frequency fm, the bandwidth of the vibration of the natural frequency F is wide, so that even if the interval between the natural frequencies of the divided sub-vibration systems 36c, 36d on the high frequency side is set wide, the divided sub-vibration systems 36c, 36d effectively contribute to vibration control, and sufficient vibration control performance can be expected. For these reasons, the vibration control device 10 is considered to exhibit an effective vibration control effect even when the natural frequency F of the house 12 is shifted to either the low frequency side or the high frequency side with respect to the representative natural frequency fm of the vibration control device 10, as shown in Fig. 6.

[0046] Also, as shown in Fig. 7, even if the house 12 to be damped has one natural frequency, the vibration characteristic graph shows a steeper slope in the lower frequency range than the natural frequency range. Therefore, it can be understood that in the high frequency range, the vibration damping effect is easily achieved even if the interval between the natural frequencies of the multiple divided vibration systems is widened, whereas in the low frequency range, it is effective to effectively achieve the vibration damping effect of the multiple divided vibration systems in the steep rise range by narrowing the interval between the natural frequencies of the multiple divided vibration systems. Note that Fig. 7 shows four divided sub-systems, and the natural frequencies f1, f2, f3, and f4 of the four divided sub-systems 36a, 36b, 36c, and 36d are set at 1 / 3 octave band intervals, with f1 set to 5 Hz, f2 set to 6.3 Hz, f3 set to 8 Hz, and f4 set to 10 Hz.

[0047] Although the embodiment of the present invention has been described above in detail, the present invention is not limited to the specific description. For example, the number of divided sub-vibration systems 36 constituting the vibration damping device 10 may be three or more, and may be three or five or more. In addition, the number of divided sub-vibration systems 36 attached to the base member 18 may be adjustable depending on the scale and vibration state of the architectural structure, for example.

[0048] When the common ratio α of the natural frequencies of the multiple divided sub-vibration systems 36 is set to 1 / N octave, the common ratio α (1 / N octave) can be calculated more accurately using a system of powers of 10 as in the above embodiment, or using a system of powers of 2. 1 / N It can also be calculated simply by:

[0049] The natural frequencies of the multiple divided sub-vibration systems 36 only need to be tuned to have geometric progression intervals at a constant ratio, and do not necessarily have to be tuned to 1 / N octave band intervals. For example, the natural frequencies of the multiple divided sub-vibration systems 36 can be set so that a common ratio is a positive constant greater than 1 that is set in consideration of the vibration state of the architectural structure.

[0050] The representative natural frequency fm of the divided sub-vibration systems 36a, 36b, 36c, and 36d is not necessarily limited to the arithmetic mean value of the minimum value f1 and the maximum value f4 of the natural frequencies of the divided sub-vibration systems. Specifically, for example, the representative natural frequency fm may be any one of the arithmetic mean value ((f1+f4) / 2) of the natural frequency f1 of the divided sub-vibration system 36a set to the lowest frequency and the natural frequency f4 of the divided sub-vibration system 36d set to the highest frequency, the median value of the natural frequencies of all the divided sub-vibration systems 36, and the natural frequency of the divided sub-vibration system 36 closest to either the arithmetic mean value or the median value of the natural frequencies of the divided sub-vibration systems 36.

[0051] The divided sub-vibration system 36 in the above embodiment has a structure in which the mass member 16 is supported by four rubber mounts 20, but may have a structure in which the mass member 16 is supported by three or fewer rubber mounts 20, or may have a structure in which the mass member 16 is supported by five or more rubber mounts 20. In addition, the shape of the mass member 16 is not limited to a rectangular plate, and may be, for example, a polygonal plate other than a rectangular shape, a polygonal column shape, a disk shape, a cylinder shape, etc.

[0052] Furthermore, the relative relationship of the natural frequency of the main vibration system to the multiple divided sub-vibration systems is not limited. For example, when a vibration damping effect is required in a specific frequency band, it is effective to set the tuning frequencies of the multiple divided vibration systems at equal intervals in that specific frequency band, and the natural frequency of the main vibration system may be anywhere within the frequency band to which the divided sub-vibration system is tuned, or it may be outside that tuning frequency band. In any of these cases, it is possible to obtain an effective vibration damping effect in the tuning frequency band of the multiple divided vibration systems.

[0053] The architectural structure is not limited to a small-scale architectural structure such as the house 12, but may be, for example, a large-scale architectural structure such as a hotel, an apartment building, or a commercial facility, or may be a store, a factory, a warehouse, or a multi-storey parking lot. The location where the vibration control device 10 is installed in the architectural structure is not necessarily limited to the ceiling space on the top floor, but may be installed, for example, in the ceiling space (under the floor) on an intermediate floor. The base member 18 may also be formed of, for example, a part of the architectural structure (such as a beam). [Explanation of symbols]

[0054] 10. Vibration damping device for architectural structures (first embodiment) 12 Houses (building structures) 14 Attic 16 Mass material 18 Base material 20 Rubber mount (spring member) 22 Rectangular frame 24a First beam material 24b Second beam material 28 Plate member 30 Rubber elastic body 32 First mounting member 34 Second mounting member 36(36a~36d) Split secondary vibration system

Claims

1. A vibration control device for an architectural structure, which configures a secondary vibration system with the architectural structure as a primary vibration system by elastically supporting a mass member with respect to the architectural structure by a spring member, The sub-vibration system includes a plurality of divided sub-vibration systems tuned to different natural frequencies, The vibration control device for architectural structures has a plurality of divided sub-vibration systems whose natural frequencies are set to be spaced at intervals in a geometric progression at a constant ratio.

2. 2. The vibration damping device for architectural structures according to claim 1, wherein the intervals between the natural frequencies of the plurality of divided sub-vibration systems are set to a 1 / N octave band.

3. the representative natural frequency of the plurality of divided sub-vibration systems is any one of an arithmetic average value of the minimum and maximum natural frequencies of the plurality of divided sub-vibration systems, an arithmetic average value of the natural frequencies of the plurality of divided sub-vibration systems, a median value of the natural frequencies of the plurality of divided sub-vibration systems, and a natural frequency of the divided sub-vibration system that is closest to either the arithmetic average value or the median value of the natural frequencies of the plurality of divided sub-vibration systems, 3. A vibration damping device for architectural structures as described in claim 1 or 2, wherein the difference between the representative natural frequency of the plurality of divided sub-vibration systems and the natural frequency of the main vibration system is 40% or less of the natural frequency of the main vibration system.

4. A vibration control device for architectural structures as described in claim 1 or 2, wherein the difference between the natural frequency of one of the multiple divided sub-vibration systems and the natural frequency of the main vibration system is smaller than half the difference between the natural frequency of the divided sub-vibration system that is closest to the natural frequency of the main vibration system on the high frequency side and the natural frequency of the divided sub-vibration system that is closest to the natural frequency of the main vibration system on the low frequency side.

5. 3. The vibration damping device for an architectural structure according to claim 1, wherein at least half of the plurality of divided secondary vibration systems have a natural frequency lower than a natural frequency of the main vibration system.

6. A tuning method for a vibration control device for an architectural structure, in which a secondary vibration system provided in an architectural structure as a primary vibration system is configured with a plurality of divided secondary vibration systems, and the divided secondary vibration systems are tuned to mutually different natural frequencies, comprising: A tuning method for a vibration control device for architectural structures, in which the natural frequencies of the plurality of divided sub-vibration systems are tuned to be spaced at intervals in a geometric progression of a constant ratio.

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