JP3736279B2 - Structural vibration control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a coupled vibration damping device in which a structure such as a high-rise or tower-like structure, which are arranged adjacent to each other independently, is coupled by an elastic body and a damper so as to attenuate mutual horizontal vibration. Regarding improvement.
[0002]
[Prior art]
Conventionally, there is a technology related to joint damping that reduces the seismic force on both structures by connecting the structures that are installed adjacent to each other independently by elastic bodies or dampers and interfering with each other. For example, it is publicly known in Japanese Patent Publication No. 54-1391.
[0003]
Recently, as shown in FIG. 9, the damper 1 and the elastic body 3 are interposed in parallel between the structures 21a and 21b, and the damping coefficient and the spring constant are optimal for the structure. It has been clarified that the damping effect can be further improved by adjusting the value.
[0004]
However, in the case of a high-rise or tower-like structure with a height of 100 meters, the most suitable elastic body 3 has an elastic capacity of several meters and a spring constant of several to several tens of TON / cm. It becomes necessary, and if such an elastic body 3 is constituted by a coil spring, it becomes a huge spring, and it is impossible not only to manufacture the elastic body 3 but also to fit the elastic body between the structures 21a and 21b. .
That is, an elastic body having a sufficient expansion / contraction ability and an optimal spring constant cannot be installed between the structures.
[0005]
Therefore, the applicant of the present application has developed a coupled vibration damping device capable of interposing an elastic body with an optimal spring constant and expansion / contraction amount between structures, and filed an application earlier (Japanese Patent Application No. 10-309107).
[0006]
FIG. 10 shows a side sectional view of the coupled vibration damping device according to this earlier application.
A connected vibration damping device 7 is provided between the tops of two adjacent structures 21a and 21b that are provided independently and adjacent to each other, and these structures 21a and 21b are connected to each other by the connected vibration damping device 7. The coupled vibration damping device 7 includes a damper 1 and an elastic body 11 that are interposed between the tops in parallel.
[0007]
A cable 11a is used as the elastic body 11, and one end of the cable 11a is fixed to the top 21c of one structure 21b, and the direction change provided on the top 21d of the other structure 21a in the middle. The other end is hung around the shaft 11b and the other end is moved to a position (ground G1 in FIG. 10) that absorbs the horizontal relative displacement generated between the fixed portion 21c of the one end and the direction changing shaft 11b. It is fixed.
[0008]
And according to this connection damping device 7, the cable 11a is used as the elastic body 11 in which a long horizontal expansion and contraction is required, and the horizontal relative displacement generated between the adjacent structures 21a and 21b is reduced. It is transmitted to the cable 11a by one end fixed to the structure 21b and the direction changing shaft 11b provided on the other structure, and is absorbed by the expansion and contraction of the entire length of the cable 11a. Since the cable 11a can freely change its routing direction by the direction changing shaft 11b, it can be changed and arranged in a direction having a sufficient installation space (in the direction of the ground G1 vertically below in FIG. 10). .
[0009]
Therefore, the elastic body 11 having an optimal spring constant and a sufficient amount of expansion and contraction can be provided equivalent to the parallel arrangement of the damper, and the structures 21a and 21b in which the elastic body 11 and the damper 1 are arranged in parallel can be provided. The coupled vibration damping device 7 can be put into practical use.
In this case, the cable 11a expands and contracts uniformly over the entire length of the cable 11a, so that the cable 11a functions as the elastic body 11 having an optimal spring constant, and the desired vibration damping effect is exhibited.
[0010]
[Problems to be solved by the invention]
However, in the above-described coupling damping device 7, a cable (hereinafter referred to as a horizontal cable) between the fixed portion 21c of the structure 21b and the direction changing shaft 11b in order to absorb the relative displacement in the horizontal direction by expansion and contraction of the cable 11a. The expansion and contraction of the vertical cable portion 11d is transmitted to the cable portion (hereinafter referred to as the vertical cable portion 11d) that is changed in direction by passing it over the direction change shaft 11b. It changes under the influence of the rotational resistance of the direction changing shaft 11b and the sliding resistance between the direction changing shaft 11b and the cable 11a.
[0011]
That is, when the resistance force is significantly smaller than the tension due to expansion and contraction, the expansion and contraction of the horizontal cable portion 11c is transmitted to the vertical cable portion 11d without being stopped by the direction changing shaft 11b, and the vertical The cable portion 11d also expands and contracts integrally with the horizontal cable portion 11c. Conversely, when the resistance force is larger than the tension due to the expansion and contraction, the expansion and contraction of the horizontal cable portion 11c causes the direction changing shaft 11b. The vertical cable portion 11d is difficult to expand and contract.
[0012]
For this reason, when the external force acting on the structures 21a and 21b is large as in an earthquake, the tension due to the expansion and contraction is remarkably large with respect to the resistance force, so that the expansion and contraction is not stopped by the direction changing shaft 11b. The expansion and contraction is transmitted to the vertical cable portion 11d, and the cable 11a can be expanded and contracted uniformly and uniformly to absorb the relative displacement. And the spring constant as the elastic body 11 can obtain the desired vibration damping effect without greatly deviating from the desired optimum spring constant.
[0013]
On the other hand, when a small external force that causes problems in terms of habitability, such as traffic vibration or vibration due to wind, acts, the resistance force is larger than the tension due to the expansion and contraction. Expansion and contraction is stopped at the conversion shaft 11b, and the tendency to expand and contract exclusively by the horizontal cable portion 11c becomes stronger. In other words, since only the horizontal cable portion 11c functions as the elastic body 11, the spring constant becomes significantly larger than the optimum spring constant designed as intended, and the desired vibration damping effect cannot be obtained. .
[0014]
That is, the above-described coupled vibration damping device has a problem that a vibration damping effect can be obtained when the external force acting on the structure is large, but is difficult to obtain when the external force is small.
[0015]
The present invention has been made in view of the above problems, and its purpose is to connect a structure with an elastic body and a damper to attenuate mutual horizontal vibrations. An object of the present invention is to provide a coupled vibration damping device capable of obtaining a stable vibration damping effect regardless of the magnitude of an external force acting on a structure.
[0016]
[Means for Solving the Problems]
As means for solving the above-mentioned problems, in the invention according to claim 1 of the present invention, adjacent structures are connected by a damper and an elastic body arranged side by side. In the coupled vibration damping device for damping an object, the elastic body includes a first cable having both ends fixed to the adjacent structure, and one end locked at an arbitrary position of the first cable. A second cable that applies a tension to the cable to bend the first cable, the second cable having the other end caused by a horizontal relative displacement between both ends of the first cable. It is characterized in that it is fixed at a position where it can be expanded and contracted by absorbing fluctuations in bending.
[0017]
According to the above configuration, one end of the second cable that applies tension to the first cable and bends the first cable is locked at an arbitrary position of the first cable whose both ends are fixed to the adjacent structure. Therefore, the relative displacement in the horizontal direction that occurs between the structures is converted into a displacement in the longitudinal direction of the second cable at the locking end, which is a bending point when the first cable is bent, and is transmitted to the second cable. It will be. Further, the other end of the second cable is fixed at a position where it can expand and contract by absorbing the displacement of the locking end caused by the relative displacement. Therefore, the relative displacement can be absorbed by expansion and contraction of the entire length of the second cable and the first cable. Further, since the arrangement direction of the second cable can be freely set, it can be stretched in a direction having a sufficient installation space.
[0018]
When the relative displacement is absorbed by the expansion and contraction of the cable, since the cable is not wound around the direction changing shaft, the transmitted cable is not easily expanded and contracted by changing the direction of the displacement. Therefore, the spring constant of the entire cable does not change depending on the magnitude of the external force acting on the structure, and the elastic body can always maintain the optimal spring constant, and the desired damper can be provided by the parallel damper. A vibration control effect can be achieved.
[0019]
The invention according to claim 2 is characterized in that, in claim 1, one end of the second cable is movably locked along the longitudinal direction of the first cable.
According to the above configuration, since the locking point of the second cable can freely move on the first cable, the locking point moves automatically so that the tension due to expansion and contraction of the first cable and the second cable is balanced. To adjust. For this reason, it can prevent that an excessive load acts on a cable, and the soundness of a cable becomes high.
[0020]
According to a third aspect of the present invention, in any one of the first and second aspects, an adjustment spring member for adjusting a spring constant of the entire elastic body is interposed at an end portion of the second cable or an arbitrary position in the middle. It is characterized by that.
According to the above configuration, the spring constant of the elastic body as a whole can be finely adjusted by directly connecting the spring, and the spring constant of the elastic body, which is one of the key components of the coupled vibration damping device, is adjusted to an optimum value. Thus, it becomes possible to maximize the capability of the coupled vibration damping device.
[0021]
According to a fourth aspect of the present invention, in any one of the first to third aspects, the elastic body and the damper are provided in parallel in a plurality of sets.
According to the above configuration, when a plurality of vibration antinodes exist in the height direction of the structure, by installing a plurality of sets of the vibration control devices according to the antinode positions, the antinode amplitude is significantly reduced. It can also cope with complicated high-order vibration modes.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.
[0023]
--- First Embodiment ---
FIG. 1 is a side sectional view of a structure provided with a coupled vibration damping device according to a first embodiment of the present invention.
A connected vibration damping device 13 is provided between the tops of two structures 21a and 21b that are adjacently and independently erected on the ground G, and these structures 21a and 21b are connected to each other by the connected vibration damping device 13. . The coupled vibration damping device 13 includes a damper 1 and an elastic body 15 that are interposed between the top portions in parallel.
[0024]
A cable 15 is used as the elastic body 15, and the cable 15 has a first cable 15 a fixed at both ends to the tops of the adjacent structures 21 a and 21 b, and one end at substantially the center of the first cable 15 a. It consists of a second cable 15b that is bound and has the other end fixed to the ground G1 and stretched. The second cable 15b applies tension to the first cable 15a, and bends the first cable 15a by bending it downward into a convex shape. It has a Y-shaped appearance.
[0025]
The elastic body 15 converts the horizontal relative displacement generated between the structures 21a and 21b into the vertical displacement of the locking point 15c, which is the bending point 15c of the first cable, and transmits it to the second cable 15b. The relative displacement can be absorbed by expansion and contraction of the entire length of the second cable 15b and the first cable 15a. At this time, since the second cable 15b is oriented in a vertical direction having a sufficient space, the second cable 15b can cope with large expansion and contraction due to a large relative displacement.
[0026]
The first cable 15a and the second cable 15b are formed by twisting wires made of wire stranded wires, each having the same diameter in the longitudinal direction, and the thickness thereof is for damping the structures 21a and 21b. It is appropriately set so as to obtain an optimal spring constant.
Further, the damper 1 may be any one that can set a desired optimum attenuation coefficient, and an oil damper, an air damper, a friction damper, or the like can be applied.
[0027]
Next, the vibration damping action of the connection vibration damping device 13 will be described with reference to FIG. When an external force is applied to the structures 21a and 21b due to an earthquake or the like, both the structures 21a and 21b roll in the horizontal direction, causing a relative displacement in the horizontal direction between them, and this displacement is particularly large at the top. Change. At this time, as shown in FIG. 2 (a), when the relative displacement increases, that is, when the two structures 21a and 21b are separated from each other, the first cable 15a bent downward is shaped into the two structures 21a. , 21b, and the bending point 15c moves upward.
At that time, the second cable 15b having one end locked to the bending point 15c is pulled upward and extends to absorb the relative displacement.
On the other hand, as shown in FIG. 2B, on the contrary, the relative displacement becomes small, that is, when the two structures 21a and 21b approach each other, the bending point 15c of the first cable 15a moves downward. At the same time, the second cable 15b is shortened to absorb the relative displacement.
That is, the relative displacement can be absorbed by the second cable 15b extending and contracting vertically.
[0028]
Since the direction changing shaft is not stretched over the first cable 15a and the second cable 15b, the expansion and contraction of the first cable 15a is possible through the vertical movement of the bending point 15c during the expansion and contraction. Therefore, the spring constant of the entire cable 15 is not changed by an external force. Accordingly, the optimum spring constant is always maintained, and a stable vibration damping effect can be obtained by the dampers 1 arranged in parallel.
[0029]
3 to 6 are side sectional views of structures provided with the coupled vibration damping devices of the second to fifth embodiments of the present invention. The basic configurations of the second to fifth embodiments are the same as those of the first embodiment. Therefore, in the figure, the same members as those in the first embodiment are denoted by the same reference numerals, and only the differences will be described below and the detailed description thereof will be omitted.
[0030]
--- Second Embodiment ---
Compared with the first embodiment, in the coupled vibration damping device of the second embodiment, the first cable 15a and the second cable 15b are not bundled, and one end of the second cable 15b is connected to the first cable 15a. It is different in that it is movably locked in the longitudinal direction.
That is, one end of the second cable 15b is locked to the central shaft 15e of the roller 15d placed on the first cable 15a, and the other end is fixed to the ground G1, thereby applying tension to the second cable 15b. Thus, the first cable 15a is bent and bent into a convex shape. The roller 15d and its central shaft 15e are configured to be rotatable relative to each other via a bearing or the like, and the roller 15d can move on the first cable 15a, that is, the locking end 15e of the second cable 15b can move. It is like that.
[0031]
According to this configuration, the locking end 15e at the end of the second cable 15b with respect to the first cable 15a can roll via the roller 15d, so that the locking end 15e is balanced so that the tension due to expansion and contraction of the cable 15 is balanced. By moving and automatically adjusting, it is possible to prevent an unreasonable load from acting on the cable 15 locally, and the soundness of the cable 15 is increased.
[0032]
--- Third Embodiment ---
As shown in FIG. 4, the connection damping device of the third embodiment is different from the first embodiment in that a spring member 17 is interposed at the end of the second cable 15b or in the middle thereof.
In order to maximize the damping capacity of the coupled damping device, it is necessary to adjust the spring constant of the elastic body 15 to an optimum value according to the structures 21a and 21b. Normally, cable specifications are determined by standards such as JIS, so fine adjustment is difficult. In contrast, in the third embodiment, a spring as an elastic body 15 is formed by connecting an adjustment spring member 17 such as a coil spring or a leaf spring in series at the end of the second cable 15b or in the middle thereof. It is possible to easily adjust the constant.
[0033]
--- Fourth Embodiment ---
As shown in FIG. 5, in the coupled vibration damping device of the fourth embodiment, the vibration damping device 13 including the elastic body 15 and the damper 1 as a set is positioned at two positions in the height direction of the structures 21 a and 21 b. In other words, the second embodiment differs from the first embodiment in that two sets of the damping device 13 are provided.
[0034]
Depending on the structures 21a and 21b, the vibration mode may be higher than primary. In the case of the primary vibration mode in which only one anti-vibration exists at the top of the structures 21a and 21b, the vibration control device can be provided in one place as in the first embodiment, but the higher-order vibration mode is prevented. In order to achieve this, it is necessary to install a plurality of sets of vibration control devices in accordance with the vibration amplitude having the largest amplitude, that is, the position of the vibration antinode.
[0035]
As a representative example of the high-order vibration mode, FIG. 5 shows a pattern of relative displacement in the secondary vibration mode in the left figure, and FIG. 5 shows a corresponding example of installation of the damping device 13 in the right figure. The secondary mode has two bellies, and is located at about one third of the height of the structures 21a and 21b from the tops of the structures 21a and 21b and the ground G. Basically, it is only necessary to install the vibration damping device 13 on the abdomen, the vibration damping device 13 on the top of the structures 21a and 21b, and a position about one third of the height of the structure from the ground G. If the vibration damping device 13 is installed in the door, a great vibration damping effect can be obtained. As an example, the case of the secondary vibration mode has been described, but a plurality of vibration control devices 13 may be similarly installed at the antinodes in other high-order modes. Further, when a plurality of vibration modes coexist, such as when the primary mode and the tertiary mode are combined, the vibration state may be investigated and the vibration damping device 13 may be installed at the antinode position.
[0036]
--- Fifth embodiment ---
As shown in FIG. 6, in the coupled vibration damping device of the fifth embodiment, the second cable 15b is locked to each of two locations of the first cable 15a, and tension is applied to the first cable 15a. The first cable 15a differs from the first embodiment in that two bending points 15c are formed. And by increasing the number of the 2nd cables 15b in this way, the spring constant as the whole elastic body 15 can be changed, and it can adjust easily to an optimal value.
[0037]
---- Application examples to other structures ---
7 and 8 show an example in which the first embodiment is applied to another structure.
FIG. 7 shows an example of application to a high-rise chimney 23 having a double cylindrical structure composed of an inner tower 23a and an outer tower 23b, and is a side sectional view at the center position.
Between the inner tower 23a and the outer tower 23b of the high-rise chimney 23, four sets of vibration damping devices 13 are installed in 90 ° increments in the circumferential direction of the inner and outer towers. In addition, horizontal vibration in an arbitrary direction can be suppressed.
[0038]
FIG. 8 shows an example of application to a core building 25 comprising a rectangular column-shaped central frame 25a standing upright independently and an outer frame 25b surrounding the periphery, and a side sectional view at the center of the vibration control device. It is.
The vibration control devices 13 of the first embodiment are respectively interposed between the four outer surfaces of the central frame 25a and the four inner surfaces of the outer frame 25b so that horizontal vibration in an arbitrary direction can be suppressed. It has become.
[0039]
As mentioned above, although embodiment of this invention was described, this invention is not limited to this embodiment, The deformation | transformation as shown below is possible in the range which does not deviate from the summary.
[0040]
(A) In this embodiment, the cable used is a twisted wire made of wire stranded wire, but is not limited to this as long as it has elasticity, and may be a resin or the like. Moreover, although the thickness was made into the same diameter over the longitudinal direction in the 1st cable and the 2nd cable, you may change it over a longitudinal direction.
[0041]
(B) In the first embodiment, the direction of switching the second cable is routed in the vertical downward direction in order to use a long space in the vertical downward direction, but may be in that direction if there is a separate space.
[0042]
(C) In the first embodiment, the second cable is bound to the first cable and the cables are integrated with each other. However, a cable that is integrally formed in a trifurcation may be used.
[0043]
【The invention's effect】
As described above, according to the first aspect of the present invention, the spring constant of the entire cable does not change depending on the magnitude of the external force acting on the structure, and the optimum spring constant can be maintained at all times. With the installed damper, the desired damping effect can always be achieved. Therefore, not only the roll caused by a large external force such as an earthquake, but also the roll caused by a small external force such as traffic vibration and wind can be suppressed as much as possible, and the comfort can be remarkably improved.
Further, the vibration damping device has a simple structure of a cable and a damper, and can be manufactured at a low cost because it can be manufactured with general-purpose products.
[0044]
According to the second aspect of the present invention, it is possible to prevent an excessive load from acting on the cable and maintain the soundness of the cable over a long period of time.
[0045]
In the invention of claim 3, it becomes easy to adjust the spring constant of the elastic body, which is one of the main components of the coupled vibration damping device, to the optimum value, and the ability of the coupled vibration damping method can be maximized, It can improve vibration control and comfort.
[0046]
In invention of Claim 4, it can respond also to a high-order vibration mode, and can further improve seismic control property and comfortability.
[Brief description of the drawings]
FIG. 1 is a side sectional view of a structure provided with a coupled vibration damping device according to a first embodiment of the present invention.
FIG. 2 is a side sectional view of a structure showing a vibration damping action of the coupled vibration damping device of the first embodiment.
FIG. 3 is a side sectional view of a structure provided with a coupled vibration damping device according to a second embodiment of the present invention.
FIG. 4 is a side sectional view of a structure provided with a coupled vibration damping device according to a third embodiment of the present invention.
FIG. 5 is a side sectional view of a structure provided with a coupled vibration damping device according to a fourth embodiment of the present invention.
FIG. 6 is a side sectional view of a structure provided with a coupled vibration damping device according to a fifth embodiment of the present invention.
FIG. 7 is a side sectional view of a high-rise chimney showing an application example of the first embodiment to a high-rise chimney composed of an inner tower and an outer tower.
FIG. 8 is a side sectional view of the core building showing an application example of the first embodiment to a core building composed of a central frame and an outer frame.
FIG. 9 is a conceptual diagram of a coupled vibration damping device including a damper and an elastic body interposed in parallel between adjacent structures.
FIG. 10 is a side sectional view of the coupled vibration damping device according to the previous application.
[Explanation of symbols]
G Ground 1 Damper 13 Connection damping device 15 Elastic body, cable 15a First cable 15b Second cable 15c Bending point, locking point 21a, 21b Structure

Claims (4)

In a connected vibration control device that suppresses horizontal vibration between both structures by connecting adjacent and independent structures with a damper and an elastic body arranged in parallel,
The elastic body has a first cable whose both ends are fixed to the adjacent structure, and one end is locked at an arbitrary position of the first cable, and tension is applied to the first cable to apply the first cable. A second cable that bends
The second cable has a structure in which the other end is fixed at a position where the fluctuation of the bending of the first cable caused by a relative displacement in the horizontal direction between the both ends of the first cable can be absorbed. Connected vibration control device for objects. 2. The connection vibration damping device for a structure according to claim 1, wherein one end of the second cable is movably locked along a longitudinal direction of the first cable. 3. The structure according to claim 1, wherein an adjustment spring member for adjusting a spring constant of the entire elastic body is interposed at an end portion of the second cable or an arbitrary position in the middle thereof. Connected vibration control device for objects. The structure damping device according to any one of claims 1 to 3, wherein the elastic body and the damper are arranged in a plurality of sets.

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