Vibration damping device

Abstract

This invention provides a vibration damping device that can achieve a state of multiple tuning, similar to dividing a weight into multiple parts, without increasing the size of the weight, thereby improving response reduction and robustness. [Solution] The lower structure 11 (vibration-damping target structure) has a weight 2 attached to its top via an additional spring 3, and an inertia mass damper 4 and a spring 5 provided in parallel with the additional spring 3 between the top of the lower structure 11 and the weight 2. The inertia mass damper 4 and the spring 5 are provided in series between the top of the lower structure 11 and the weight 2, and the inertia mass damper 4 has an inertia mass element 6 and a viscous damping element 7 (damping element), and the inertia mass element 6 and the viscous damping element 7 are provided in parallel between the weight 2 and the spring 5.

Description

Technical Field

[0001] The present invention relates to a vibration control device.

Background Art

[0002] As a vibration control technology for super high-rise buildings, a vibration control device called a tuned mass damper or a dynamic absorber (hereinafter referred to as TMD) is known, which adds a weight to the top (mainly the rooftop) of the building to be vibration-controlled and tries to cancel out the vibration of the building by its sway (see, for example, Patent Document 1). In recent years, from the conventional TMD for suppressing wind sway, large-sized TMDs that also exhibit effects even when the building is greatly deformed such as by seismic motion have been developed and have already been adopted in a plurality of buildings. Note that the TMD for suppressing wind sway has a mass ratio of less than 1%, while the TMD for earthquake usually secures a mass ratio μ of 2% or more in consideration of robustness in addition to the response reduction effect. The mass ratio μ is the ratio of the mass M of the weight to the equivalent mass M of the building (μ = (M TMD / M). TMD / M).

[0003] TMD has the property that the vibration control effect becomes higher as the mass ratio μ increases. The additional damping constant h a due to the installation of TMD in a building can be roughly calculated by the following formula (1) using the mass ratio μ. The additional damping constant h a has a relationship that is approximately proportional to the square root of the mass ratio μ. h a ≒0.3√(μ) ···(1)

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] There is a trade-off relationship between the response reduction effect and the mass ratio μ. If one attempts to increase the response reduction effect, the mass M of the weight TMD That is, the weight must be made larger, and a large space for installing the large weight is required at the top of the building (mainly the rooftop). However, in reality, it is not always possible to secure a large space for installing a large weight on the rooftop, and there is a problem that the weight cannot be made sufficiently large. That is, there is a need for a vibration control device that can achieve greater response reduction while ensuring robustness with a limited weight size. Also, a vibration control device (multiple dynamic vibration absorber) is known that uses multiple TMDs to disperse their respective tuning periods to enhance robustness while simultaneously improving the response reduction effect. However, such a vibration control device also has problems such as the need to install additional springs and damping elements between each of the divided weights and the top of the building because the weights of the multiple TMDs are divided and made independent, resulting in an increase in the number of components and an increase in cost.

[0006] Therefore, an object of the present invention is to provide a vibration control device that can achieve an improved response reduction effect and robustness by realizing a multi-tuning state in which the tuning periods are dispersed, similar to dividing the weight into multiple parts, without increasing the size of the weight.

Means for Solving the Problem

[0007] To achieve the above object, the vibration control device according to the present invention includes a weight added to the top of a vibration control target structure via an additional spring, and an inertial mass damper and a spring provided in parallel with the additional spring between the top of the vibration control target structure and the weight. The inertial mass damper and the spring are provided in series between the top of the vibration control target structure and the weight. The inertial mass damper has an inertial mass element and a damping element, and the inertial mass element and the damping element are provided in parallel between the weight and the spring.

[0008] In this invention, an inertia mass damper, which has an inertia mass element and a damping element arranged in parallel, and a spring are arranged in series between the top of the structure to be damped and a weight, and the period of the vibration system formed by the inertia mass damper and spring is synchronized with the period of the vibration system formed by the additional spring and weight. As a result, compared to conventional vibration damping devices in which a spring and a damping element are arranged in parallel between the top of the structure to be damped and a weight, the response reduction effect and robustness can be improved. Thus, in the vibration damping device of the present invention, the robustness and response reduction effect of the vibration damping device can be improved without increasing the size of the weight or dividing the weight into multiple parts and providing springs or viscous damping elements between each divided weight and the top of the structure to be damped. In the vibration damping device of the present invention, a state of multiple synchronization, in which the synchronization periods are dispersed without dividing the weight, can be achieved. In the vibration damping device of the present invention, since there is no need to divide the weight, a multi-tuning vibration damping device can be realized at a relatively low cost without increasing the number of components.

[0009] In the vibration damping device according to the present invention, the period of the vibration system formed by the inertial mass damper and the spring may be set to synchronize with the period of the vibration system formed by the additional spring and the weight.

[0010] This configuration enables the realization of a multi-synchronization state. Furthermore, this configuration creates four fixed points in the relationship between the period and the response magnification. Approximating the response magnification values ​​of these fixed points, the greater the distance between the fixed points, the greater the robustness. In conventional vibration damping devices, where a spring and a damping element are arranged in parallel between the top of the structure to be damped and a weight, there are only two fixed points. Therefore, increasing the number of fixed points to four improves robustness.

[0011] In the vibration damping device according to the present invention, the mass ratio of the inertial mass element to the weight may be 0.1 to 0.06.

[0012] By adopting this configuration, the response magnification can be reduced, and the response reduction effect can be improved.

[0013] In the vibration damping device according to the present invention, a state of multiple tuning may be achieved.

[0014] This configuration allows for reduced response time and improved robustness.

[0015] The vibration damping device according to the present invention comprises an upper weight provided above the weight via an upper additional spring, and an upper inertia mass damper and an upper spring provided in parallel with the upper additional spring between the weight and the upper weight, wherein the upper inertia mass damper and the upper spring are provided in series between the weight and the upper weight, and the upper inertia mass damper comprises an upper inertia mass element and an upper damping element, wherein the upper inertia mass element and the upper damping element may be provided in parallel between the upper weight and the upper spring.

[0016] The vibration damping device according to the present invention may include an upper weight provided above the weight via an upper additional spring, and an upper damping element provided between the weight and the upper weight in parallel with the upper additional spring.

[0017] This configuration improves robustness and response reduction effects, and enables the realization of multiple tunings, even when multiple weights are arranged vertically (multi-stage). [Effects of the Invention]

[0018] According to the present invention, a state of multiple tuning similar to that achieved by dividing the weight into multiple parts can be realized without increasing the size of the weight, thereby improving response reduction and robustness. [Brief explanation of the drawing]

[0019] [Figure 1] This is a model diagram of a vibration damping device according to the first embodiment. [Figure 2] This is a model diagram of a conventional vibration damping device. [Figure 3] This graph shows the relationship between the period and response magnification of a vibration damping device according to the first embodiment and a conventional vibration damping device. [Figure 4] It is a graph showing the relationship between the period and the response magnification factor of a conventional vibration control device. [Figure 5] It is a front view of the vibration control device according to the second embodiment. [Figure 6] It is a model diagram of the vibration control device according to the second embodiment. [Figure 7] It is a model diagram of the vibration control device according to the third embodiment. [Figure 8] It is a graph showing the resonance curve of the weight (two-mass points). [Figure 9] It is a graph showing the resonance curve of the lower structure (two-mass points). [Figure 10] It is a table showing the time history response analysis results of the input ground motion with respect to BCJ-L2 (two-mass points). [Figure 11] It is a graph showing the resonance curve of the lower structure (four-mass points). [Figure 12] It is a table showing the time history response analysis results of the input ground motion with respect to BCJ-L2 (four-mass points).

Embodiments for Carrying Out the Invention

[0020] (First Embodiment) Hereinafter, the vibration control device according to the first embodiment of the present invention will be described based on FIGS. 1 to 4. As shown in FIG. 1, the vibration control device 1 according to the first embodiment is provided at the top of the lower structure 11 which is a vibration control target structure. The lower structure 11 is, for example, a high-rise building or the like. The lower structure 11 is supported by the ground 13 (support) via the support spring element 12. In FIG. 1, the vibration control device 1 is shown as a mass system.

[0021] The vibration control device 1 includes a weight 2 (m TMD ), an additional spring 3 (k TMD ), an inertial mass damper 4 (m d , c d ), and a spring 5 (k d ). The inertial mass damper 4 includes an inertial mass element 6 (m d ) and a viscous damping element 7 (c dThe weight 2 is connected to the lower structure 11 via an additional spring 3. That is, the weight 2 is attached to the lower structure 11 via an additional spring 3. The inertia mass damper 4 and the spring 5 are arranged in series. The inertia mass damper 4 and the spring 5, arranged in series, are provided in parallel with the additional spring 3 between the weight 2 and the lower structure 11.

[0022] Figure 2 shows a conventional vibration damping device 101 (conventional TMD) as a mass system. In the conventional vibration damping device 101, similar to the vibration damping device 1 of this embodiment, the weight 2 is connected to the lower structure 11 via an additional spring 3. A viscous damping element 107 is provided between the weight 2 and the lower structure 11 in parallel with the additional spring 3. The conventional vibration damping device 101 does not have an inertial mass element 6 and a spring 5.

[0023] Figure 3 shows the values ​​of the viscous damping element 7 in both the conventional vibration damping device 101 and the vibration damping device 1 according to this embodiment (c d The relationship between the period and response magnification when ) is smaller than the optimal value is shown by the dashed line, and the value of the viscous damping element 7 (c d The solid line shows the relationship between the period and the response magnification when the height of the fixed point is at the position of the peak of the curve, which is the optimal state. Figure 4 shows the value of the viscous damping element 7 (c) in the conventional vibration damping device 101. d The relationship between the period and response magnification when ) is smaller than the optimal value is shown by the dashed line, and the value of the viscous damping element 7 (c d The solid line shows the relationship between the period and the response magnification when the height of the fixed point is at the peak position of the curve, which is the optimal state. As shown in Figures 3 and 4, the conventional vibration damping device 101 has two fixed points, whereas the vibration damping device 1 according to this embodiment has four fixed points. In the vibration damping device 1 of this embodiment, the parameters of the inertial mass element 6 of the inertial mass damper 4, the viscous damping element 7, and the spring 5 are set so that the vibration system consisting of the spring 5 and the inertial mass damper 4 is synchronized with the period of the vibration system consisting of the weight 2 and the additional spring 3. Specifically, the viscous damping element 7(c d ), inertial mass element 6 (m d ) and spring 5(k dThe specifications of the device are set. In this way, if the distance between fixed points represents robustness, then the vibration damping device 1 according to this embodiment has four more fixed points than the conventional vibration damping device 101, resulting in a larger distance between fixed points and improved robustness. Furthermore, the maximum response magnification value of the vibration damping device 1 according to this embodiment is also smaller than that of the conventional vibration damping device 101.

[0024] In addition, the inertial mass element 6(m d Regarding the specifications of the weight 2 (m TMD The mass ratio (μ') to (μ'=m) should be set to 0.1 to 0.06 (μ'=m d / m TMD (=0.1~0.06). This allows for a smaller response magnification, improving the response reduction effect. However, if the mass ratio (μ') exceeds 0.1 or falls below 0.06, the response magnification may actually increase.

[0025] Natural period of weight 2 (T tmd ) is based on the fixed-point theory, T tmd ≈T / λ Here, λ = (1 + μ) μ: Mass ratio between weight 2 and lower structure 11 T: Natural period of the substructure 11 It is approximately 1.1 times.

[0026] In the vibration damping device 1 according to the first embodiment, an inertial mass damper 4, which has an inertial mass element 6 and a viscous damping element 7 arranged in parallel, and a spring 5 are arranged in series between the lower structure 11 and the weight 2. The specifications of the inertial mass element 6 of the inertial mass damper 4, the viscous damping element 7, and the spring 5 are set so that the vibration system consisting of the spring 5 and the inertial mass damper 4 is synchronized with the period of the vibration system consisting of the weight 2 and the additional spring 3. As a result, the response reduction effect and robustness can be improved compared to the conventional vibration damping device 101. Thus, in the vibration damping device 1 according to the first embodiment, the robustness and response reduction effect of the vibration damping device 1 can be improved without increasing the size of the weight 2 or dividing the weight 2 into multiple parts and providing springs 5 ​​and viscous damping elements 7 between each divided weight and the lower structure 11. Furthermore, in the vibration damping device 1 according to the first embodiment, a state of multiple synchronization, in which the synchronization period is dispersed without dividing the weight 2, can be achieved. In the vibration damping device 1 according to the first embodiment, since there is no need to divide the weight 2, a multi-tuned vibration damping device (TMD) can be realized at a relatively low cost without increasing the number of components.

[0027] Next, other embodiments will be described. The same reference numerals will be used for components and parts identical or similar to those in the first embodiment described above, and their descriptions will be omitted. Configurations different from the first embodiment will be described.

[0028] (Second Embodiment) As shown in Figure 5, the vibration damping device 1B according to the second embodiment has three weights 21, 22, and 23 arranged vertically on the lower structure 11. In other words, the vibration damping device 1B according to the second embodiment has multiple weights. The three weights 21, 22, and 23 are denoted as the first weight 21, the second weight 22, and the third weight 23, from bottom to top. The first weight 21 corresponds to the weight in the claims. The second weight 22 corresponds to the upper weight in the claims. Figure 6 shows a model diagram of the vibration damping device 1B.

[0029] The lower structure 11 and the first weight 21 are connected via an additional spring 31 and also via an inertia mass damper 41 and a spring 51. The inertia mass damper 41 and the spring 51 are arranged in series. The inertia mass damper 41 and the spring 51, arranged in series, are arranged in parallel with the additional spring 31. The inertia mass damper 41 has inertia mass elements 61 and viscous damping elements 71 arranged in parallel.

[0030] The first weight 21 and the second weight 22 are connected via an additional spring 32 and also via an inertia mass damper 42 and a spring 52. The inertia mass damper 42 and the spring 52 are arranged in series. The inertia mass damper 42 and the spring 52, arranged in series, are arranged in parallel with the additional spring 32. The inertia mass damper 42 has an inertia mass element 62 and a viscous damping element 72 arranged in parallel. The additional spring 32, the inertia mass damper 42, the spring 52, the inertia mass element 62 and the viscous damping element 72 correspond to the upper additional spring, upper inertia mass damper, upper spring, upper inertia mass element and upper damping element in the claims.

[0031] The second weight 22 and the third weight 23 are connected via an additional spring 33, and also via an inertia mass damper 43 and a spring 53. The inertia mass damper 43 and the spring 53 are arranged in series. The inertia mass damper 43 and the spring 53 arranged in series are arranged in parallel with the additional spring 33. The inertia mass damper 43 has an inertia mass element 63 and a viscous damping element 73 arranged in parallel.

[0032] In the vibration damping device 1B according to the second embodiment, even when multiple weights 21-23 are arranged in the vertical direction, robustness and response reduction effects can be improved, and a state of multiple tuning can be achieved.

[0033] (Third embodiment) As shown in Figure 7, the vibration damping device 1C according to the third embodiment, like the vibration damping device 1B according to the second embodiment, has three weights 24, 25, and 26 arranged vertically on the lower structure 11. In other words, in the vibration damping device 1C according to the third embodiment, the weights are arranged in multiple stages. The three weights 24, 25, and 26 will be referred to as the first weight 24, the second weight 25, and the third weight 26, from bottom to top. The first weight 24 corresponds to the weight in the claims. The second weight 25 corresponds to the upper weight in the claims.

[0034] The lower structure 11 and the first weight 24 are connected via an additional spring 34 and also via an inertia mass damper 44 and a spring 54. The inertia mass damper 44 and the spring 54 are arranged in series. The inertia mass damper 44 and the spring 54 arranged in series are arranged in parallel with the additional spring 34. The inertia mass damper 44 has inertia mass elements 64 and viscous damping elements 74 arranged in parallel.

[0035] The first weight 24 and the second weight 25 are connected via an additional spring 35 and also via a viscous damping element 75. The additional spring 35 and the viscous damping element 75 correspond to the upper additional spring and upper damping element in the claims. The additional spring 35 and the viscous damping element 75 are arranged in parallel. The second weight 25 and the third weight 26 are connected via an additional spring 36 and also via a viscous damping element 76.

[0036] In the vibration damping device 1C according to the third embodiment, even when multiple weights 24-26 are arranged in the vertical direction, robustness and response reduction effects can be improved, and a state of multiple tuning can be achieved.

[0037] (Example of consideration) Here, we will examine the specific specifications of the inertial mass damper 4 and spring 5 (m) for the vibration damping device 1 according to this embodiment, shown in Figure 1, and the conventional vibration damping device 101 (conventional TMD), shown in Figure 2, which are based on a two-mass system. d ,c d ,k d This explains the setup procedure. (Step 1) The rigidity parameters of the conventional vibration damping device 101 are set for the substructure 11 using the fixed-point theory. (Step 2) Equivalent inertial mass m of the inertial mass damper 4 of the vibration damping device 1 according to this embodiment d and the mass m of weight 2 of TMD TMD Set this arbitrarily so that the mass ratio μ is between 0.1 and 0.06. Using the fixed-point theory, the stiffness parameters and viscous damping coefficients of the inertial mass damper 4 and spring 5 are set for the period of the conventional vibration damping device 101 obtained in step 1 above.

[0038] An example of an examination using the above steps 1 and 2 is shown. The specifications are as follows: Period T of lower structure 11 = 2.0 seconds Mass M of the lower structure 11 = 1000 tons The stiffness of the substructure 11 is K = 9869.6 kN / m Mass m of weight 2 TMD = 50 tons The mass ratio μ of weight 2 to lower structure 11 is 50 / 1000 = 0.05

[0039] (Step 1) In the fixed-point theory, the optimal frequency ratio γ = (1 / 1 + μ) = 0.9524 Optimal damping constant h in fixed-point theory opt =[3μ / {8(1+μ)}]^ (1 / 2) =0.1336 Optimal stiffness k TMD ={2π / (T / γ)}^ 2 xm TMD = 447.6 kN / m Optimal damping coefficient c d =2h opt / {2π / (T / γ)}×k TMD = 40.0 kNs / m

[0040] (Step 2) Equivalent inertial mass m of inertial mass damper 4 d = 10 tons The equivalent inertia mass ratio μ' is set to μ' = 4 / 50 = 0.08. Optimal frequency ratio γ' in fixed-point theory ={1-(1-4μ')^ (1 / 2)} / (2μ')=1.096 Optimal damping constant h in fixed-point theory opt =[3{1-(1-4μ')^ (1 / 2)}]^(1 / 2) / 4 = 0.181 Optimal stiffness k d ={2π / (T' / γ')}^2×m d = 43.0 kN / m Optimal damping coefficient c d =2h opt ×{2π / (T' / γ')}×m d = 4.76 kNs / m Here, T' = T / γ

[0041] Figures 8 and 9 show the resonance curves of the conventional vibration damping device 101 and the vibration damping device 1 of this embodiment, with the absolute acceleration response magnification on the vertical axis. As shown in Figures 8 and 9, it can be confirmed that the maximum value of the response magnification of the lower structure 11, which is the target of vibration damping, is reduced in the vibration damping device 1 of this embodiment compared to the conventional vibration damping device 101. Furthermore, as shown in Figure 10, the results of the time history response analysis with the input seismic motion set to BCJ-L2 (maximum acceleration 356 gal) also confirm that the vibration damping device 1 of this embodiment has a superior response reduction effect on the substructure 11 compared to the conventional vibration damping device 101.

[0042] Next, we will present an example of a vibration damping device 1B with a 4-mass system where the weights are arranged in multiple stages (an example of 3 stages), as shown in Figure 6. The setup procedure is the same as that for the 2-mass system described above.

[0043] The specifications are as follows: Period T of lower structure 11 = 2.0 seconds Mass M of the lower structure 11 = 1000 tons The stiffness of the substructure 11 is K = 9869.6 kN / m The mass m of the third weight 23 of the TMD TMD ,3 = 50 tons The mass ratio μ of weight 2 to lower structure 11 is 50 / 1000 = 0.05 Also, the mass m of the second weight 22 TMD,2 = 1 ton, mass m of the first weight 21 TMD,1 Let's assume it equals 1 ton.

[0044] Furthermore, the parameters of the inertial mass damper 4, which were determined using a two-mass system, are assigned values ​​that are uniformly tripled at each stage. Equivalent inertial mass m of dampers 41, 42, and 43 in each stage d,1 ,m d,2 ,m d,3 m d,3 =m d,2 =m d,1 = 43.0 kN / m × 3 = 129 kN / m Damping coefficient c of the inertial mass dampers 41, 42, and 43 for each stage d,1 ,c d,2 ,c d,3 c d,3 =c d,2 =c d,1 = 4.76 kNs / m × 3 = 14.3 kNs / m

[0045] As shown in Figure 11, it can be confirmed that the maximum response magnification of the lower structure 11, which is the target of vibration damping, is reduced in the vibration damping device 1B (multi-stage) of this embodiment compared to the conventional vibration damping device 101.

[0046] As shown in Figure 12, the results of the time history response analysis with the input seismic motion set to BCJ-L2 (maximum acceleration 356 gal) confirm that, similar to the case of a two-mass system, the vibration control device 1B (multi-stage) according to this embodiment has a superior response reduction effect on the substructure 11.

[0047] Although embodiments of the vibration damping device according to the present invention have been described above, the present invention is not limited to the embodiments described above and can be modified as appropriate without departing from the spirit of the invention. For example, in the above embodiment, the inertia mass damper 4 has a viscous damping element 7(c d Although a viscous damping element 7 is provided, damping elements other than the viscous damping element 7 may also be provided. The period of the vibration system formed by the inertial mass damper 4 and spring 5, and the period of the vibration system formed by the additional spring 3 and weight 2, may be set to values ​​other than those described above as appropriate. The mass ratio μ' of the inertial mass element 6 to the weight 2 may be set appropriately in addition to the above.

[0048] The Sustainable Development Goals (SDGs) are among the 17 international goals adopted at the UN Summit in September 2015. The vibration damping device according to this embodiment can contribute to achieving one of the 17 Sustainable Development Goals (SDGs), such as Goal 11, "Make cities and human settlements inclusive, safe, resilient and sustainable." [Explanation of Symbols]

[0049] 1,1B,1C Vibration damping device 2,21-26 Weight 3,31-36 Additional spring 4,41-44 Inertial Mass Damper 5,51-54 Spring 6,61-64 Inertial mass element 7,71-76 Viscous damping elements 11. Substructure (object to be damped) 21,24 1st spindle 22,25 2nd spindle 23,26 3rd spindle 100 Vibration damping device 101 Vibration damping device

Claims

1. A weight attached to the top of the vibration-damping structure via an additional spring, The structure has an inertia mass damper and a spring provided in parallel with the additional spring between the top of the vibration-damping target structure and the weight, The inertial mass damper and the spring are provided in series between the top of the vibration-damping structure and the weight. The aforementioned inertial mass damper comprises an inertial mass element and a damping element, The inertial mass element and the damping element are vibration damping devices provided in parallel between the weight and the spring.

2. The vibration damping device according to claim 1, wherein the period of the vibration system formed by the inertial mass damper and the spring is set to be in synchronization with the period of the vibration system formed by the additional spring and the weight.

3. The vibration damping device according to claim 1 or 2, wherein the mass ratio of the inertial mass element to the weight is 0.1 to 0.

06.

4. A vibration damping device according to claim 1 or 2 that achieves a state of multiple synchronization.

5. An upper weight is provided above the aforementioned weight via an upper additional spring, The upper inertia mass damper and upper spring are provided in parallel with the upper additional spring between the weight and the upper weight, The upper inertia mass damper and the upper spring are provided in series between the weight and the upper weight. The upper inertial mass damper comprises an upper inertial mass element and an upper damping element, The vibration damping device according to claim 1 or 2, wherein the upper inertial mass element and the upper damping element are provided in parallel between the upper weight and the upper spring.

6. An upper weight is provided above the aforementioned weight via an upper additional spring, The vibration damping device according to claim 1 or 2, further comprising an upper damping element provided in parallel with the upper additional spring between the weight and the upper weight.

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