Novel low-frequency tuned mass damper
By designing a new low-frequency tuning mass damper, using a combination of U-shaped seat, mass block, damping shock absorber and gear transmission mechanism, the problem of difficulty in controlling the vortex vibration of the bridge under medium and low frequency conditions in the prior art is solved, and a more efficient vibration damping effect and lower manufacturing deviation are achieved.
Patent Information
- Application Number
- CN202422310837.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-23
- Publication Date
- 2025-06-06
- Estimated Expiration
- 2034-09-23
AI Technical Summary
Existing tuned mass dampers are difficult to effectively control the vortex vibration of the bridge under low-frequency conditions, resulting in large static deformation of the spring, large manufacturing deviations, and frequency deviations that cannot meet engineering requirements.
A new low-frequency tuning mass damper is designed, using a combination of U-shaped seat, mass block, damping shock absorber and gear transmission mechanism to shorten the static deformation of the spring through the gear transmission mechanism, increase the spring stiffness and reduce manufacturing deviation.
It effectively shortens the static deformation of the spring, reduces manufacturing deviation, improves the vibration reduction effect on the bridge, and meets the requirements for frequency deviation in the project.
Smart Images
Figure CN222950302U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of tuned mass dampers, in particular to a novel low-frequency tuned mass damper. Background Art
[0002] In recent years, many large-span suspension bridges at home and abroad have experienced obvious vortex-induced vibration problems, which has attracted widespread attention from the whole society; people have begun to pay attention to and discuss topics related to the vibration theory and vibration control of bridge structures. For example: the vibration frequency of the Yingwuzhou Yangtze River Bridge is 0.23Hz, the vibration frequency of the Humen Bridge is 0.24Hz, and the vibration frequency of the Zhoushan Cross-sea Bridge (Xihoumen Bridge) is 0.32Hz. The vibration frequencies of these three large-span suspension bridges are all lower than 0.4Hz.
[0003] With the continuous development of technology, the span of bridges has increased, and the materials have become lighter and more flexible, making the overall structural mass of the bridge lighter, the structural stiffness lower, and the inherent frequency lower; when subjected to wind loads, the bridge is prone to produce obvious vortex-induced vibrations, which have the characteristics of large vibration amplitude, long periodicity, and easy structural fatigue.
[0004] Previous cases have proved that installing a tuned mass damper on a bridge can effectively control the vortex-induced vibration of the bridge. The tuned mass damper (TMD) is a common passive control damper, which mainly consists of three parts: mass system, spring system and damping system. Through the resonance principle, the vibration of the main structure is amplified and transmitted to the mass system of the tuned mass damper, and the energy is dissipated through the damping system to achieve effective control of bridge vibration.
[0005] When conventional tuned mass dampers (TMDs) are used for low-frequency vortex-induced vibration control, as the vibration frequency decreases, the spring stiffness decreases, and the static deformation of the spring increases rapidly. The static deformation of a 0.23Hz spring is 4.73m, the static deformation of a 0.24Hz spring is 4.34m, and the static deformation of a 0.32Hz spring is 2.44m. Considering the size of other components and the operating space during installation, the size of the existing bridge steel box girder is far from meeting the space requirements for installing conventional tuned mass dampers. In practice, when the static compression of the compression spring is large, it will cause problems such as lateral buckling instability, substandard shear stress, and difficulty in installation.
[0006] The vibration reduction effect of the tuned mass damper is very sensitive to the frequency deviation. In engineering practice, the frequency deviation of the tuned mass damper under different amplitude conditions is not allowed to exceed ±1%. Since the vibration frequency of the long-span suspension bridge is low and the static deformation of the spring is large, the difficulty of spring processing and manufacturing is increased, which invisibly increases the frequency deviation of the tuned mass damper, and thus cannot achieve the best vibration reduction effect, and cannot meet the requirements of the bridge in engineering to resist vortex-induced vibration. Utility Model Content
[0007] The purpose of the utility model is to provide a new low-frequency tuned mass damper that solves the problem that conventional tuned mass dampers are difficult to control vortex-induced vibration of bridges under low-frequency conditions, and effectively solves the problems raised in the above-mentioned background technology.
[0008] A novel low-frequency tuned mass damper includes a U-shaped seat, a mass block and a damping shock absorber. Top plates are installed at both ends of the U-shaped seat. Two movable plates parallel to each other are arranged on both sides of the interior of the U-shaped seat. Springs are arranged on opposite sides of the two movable plates in the length direction. The mass block is arranged inside the U-shaped seat and between the movable plates on both sides. The damping shock absorber is installed inside the U-shaped seat, and the end of the telescopic end of the damping shock absorber is connected to the lower surface of the mass block. Gear transmission mechanisms are arranged between the outer surfaces of both sides of the mass block and the movable plates on both sides. The gear transmission mechanism is used to shorten the static deformation of the spring.
[0009] Preferably, the gear transmission mechanism includes a first tooth plate installed together on the outer surfaces of the two movable plates, a second tooth plate is installed on the side surface of the mass block, a pinion and a large gear are arranged between the second tooth plate and the first tooth plate, and the pinion is meshed with the large gear, and the pinion is meshed with the first tooth plate, and the second tooth plate is meshed with the large gear.
[0010] Preferably, two side plates are installed on the inner walls on both sides of the U-shaped seat, and the first rotating shaft and the second rotating shaft are rotatably installed between the two side plates. The small gear is installed on the outer surface of the first rotating shaft, and the large gear is installed on the outer surface of the second rotating shaft.
[0011] Preferably, two sliding rods are connected between the U-shaped seat and the top plate, and the spring is sleeved on the outer surface of the sliding rod. Linear bearings are installed at both ends of the movable plate in the length direction, and the linear bearings are slidably installed on the outer surface of the sliding rod.
[0012] Preferably, the two springs on the outer surface of the slide bar are both in a compressed state.
[0013] Preferably, the number of the damping shock absorbers is four, and the four damping shock absorbers are respectively arranged at the four corners of the lower surface of the mass block.
[0014] Compared with the prior art, the utility model has the following beneficial effects:
[0015] (1) The utility model has top plates installed at both ends of the U-shaped seat, and two movable plates parallel to each other are arranged on both sides of the interior of the U-shaped seat, and springs are arranged on the opposite surfaces of the two movable plates at both ends in the length direction. The mass block is arranged inside the U-shaped seat and between the movable plates on both sides, and the damping shock absorber is installed inside the U-shaped seat, and the end of the telescopic end of the damping shock absorber is connected to the lower surface of the mass block. Gear transmission mechanisms are arranged between the outer surfaces of both sides of the mass block and the movable plates on both sides. The gear transmission mechanism is used to shorten the static deformation of the spring. When vibration occurs, the mass block swings up and down, and the vibration reduction effect on the bridge is achieved through the joint action of the spring and the damping shock absorber. In addition, through the setting of the gear transmission mechanism, the spring stiffness is amplified and the static deformation of the spring is shortened, thereby effectively reducing the manufacturing deviation of the tuned mass damper and improving the vibration reduction effect on the bridge.
[0016] (2) The utility model sets a gear transmission mechanism. When the mass block vibrates downward, the second tooth plate drives the large gear to rotate clockwise. Through the transmission action of the large gear and the small gear, the first tooth plate is driven to move downward, and the upper spring is stretched and the lower spring is compressed. When the mass block vibrates upward, the second tooth plate drives the large gear to rotate counterclockwise, so the upper spring is compressed and the lower spring is stretched through the first tooth plate. Therefore, the stiffness coefficient of the spring end is magnified and the static deformation of the spring end is shortened through gear transmission, thereby effectively reducing the manufacturing deviation of the tuned mass damper and improving the vibration reduction effect on the bridge. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 It is a three-dimensional schematic diagram of the overall structure of the utility model;
[0018] Figure 2 This is a front view structural schematic diagram of the utility model;
[0019] Figure 3 It is a schematic diagram of the top view structure of the utility model;
[0020] Figure 4 It is a structural schematic diagram of the gear transmission mechanism in the utility model. DETAILED DESCRIPTION
[0021] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.
[0022] like Figures 1 to 4As shown, a novel low-frequency tuned mass damper includes a U-shaped seat 100, a top plate 101, a movable plate 102, a spring 103, a mass block 104, a damping shock absorber 105, a gear transmission mechanism 200, a first tooth plate 201, a second tooth plate 202, a small gear 203, a large gear 204, a side plate 300, a first rotating shaft 301, a second rotating shaft 302, a sliding rod 400, and a linear bearing 401.
[0023] In the description of the present invention, unless otherwise specified, "multiple" means two or more; the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third" and the like are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.
[0024] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0025] like Figures 1 to 4 As shown, a top plate 101 is installed at both ends of the U-shaped seat 100, and two parallel movable plates 102 are arranged on both sides of the interior of the U-shaped seat 100. Springs 103 are arranged on the opposite sides of the two movable plates 102 in the length direction. When vibration occurs, one of the springs 103 on the upper and lower sides is compressed and the other is stretched. The interaction between the two can make the mass block 104 quickly stabilize and improve the vibration reduction effect on the bridge. The mass block 104 is arranged inside the U-shaped seat 100 and located between the movable plates 102 on both sides. The damping shock absorber 105 is installed inside the U-shaped seat 100, and the end of the telescopic end of the damping shock absorber 105 is connected to the lower surface of the mass block 104. Through the joint action of the spring 103 and the damping shock absorber 105, the vibration reduction effect on the bridge is achieved.
[0026] Gear transmission mechanisms 200 are provided between the outer surfaces of both sides of the mass block 104 and the movable plates 102 on both sides. The gear transmission mechanisms 200 are used to shorten the static deformation of the spring 103. By shortening the static deformation of the end of the spring 103, the manufacturing deviation of the tuned mass damper can be effectively reduced, and the vibration reduction effect on the bridge can be improved. There are four damping shock absorbers 105, and the four damping shock absorbers 105 are respectively arranged at the four corners of the lower surface of the mass block 104. Through the arrangement of the four damping shock absorbers 105, a stable and reliable damping effect can be provided for the mass block 104, so that the bridge can be quickly stabilized and the vibration reduction effect of the bridge can be improved.
[0027] The gear transmission mechanism 200 includes a first tooth plate 201 installed together on the outer surfaces of the two movable plates 102, a second tooth plate 202 is installed on the side surface of the mass block 104, a small gear 203 and a large gear 204 are arranged between the second tooth plate 202 and the first tooth plate 201, and the small gear 203 is meshed with the large gear 204, and the small gear 203 is meshed with the first tooth plate 201, and the second tooth plate 202 is meshed with the large gear 204. When the mass block 104 vibrates downward, the second tooth plate 202 drives the large gear 204 to rotate clockwise, and through the transmission action of the large gear 204 and the small gear 203, the first tooth plate 201 is driven to move downward, and the upper spring 103 is stretched, and the lower spring 103 is tightened. Compression, when the mass block 104 vibrates upward, the second tooth plate 202 drives the large gear 204 to rotate counterclockwise, so the upper spring 103 is compressed through the first tooth plate 201, and the lower spring 103 is stretched. Therefore, the stiffness coefficient of the spring 103 end is amplified and the static deformation of the spring 103 end is shortened through gear transmission, thereby effectively reducing the manufacturing deviation of the tuned mass damper and improving the vibration reduction effect on the bridge; in practical applications, considering the actual situation of the project, the gear transmission ratio is adjusted to appropriately shorten the static deformation of the spring 103; the overall size of the small low-frequency tuned mass damper is reduced to meet the internal installation space of the steel box girder of the bridge, effectively solving the problem of low-frequency vortex-induced vibration of large-span suspension bridges.
[0028] Two side plates 300 are installed on the inner walls on both sides of the U-shaped seat 100, and a first rotating shaft 301 and a second rotating shaft 302 are rotatably installed between the two side plates 300. The small gear 203 is installed on the outer surface of the first rotating shaft 301, and the large gear 204 is installed on the outer surface of the second rotating shaft 302. Through the arrangement of the side plates 300, the first rotating shaft 301 and the second rotating shaft 302, the transmission effect of the small gear 203 and the large gear 204 can be realized, and they are always kept in a meshing state.
[0029] Two slide bars 400 are connected between the U-shaped seat 100 and the top plate 101, and the spring 103 is sleeved on the outer surface of the slide bar 400. Linear bearings 401 are installed at both ends of the length direction of the movable plate 102, and the linear bearings 401 are slidably installed on the outer surface of the slide bar 400. Through the arrangement of the slide bar 400 and the linear bearing 401, a stable support and guide can be provided for the movable plate 102, which helps to reduce the displacement and shaking of the movable plate 102 during the up and down movement. The slide bar 400 also provides a guiding and limiting effect for the spring 103, so that the spring 103 can only be extended and retracted along the length direction of the slide bar 400, avoiding bending and deformation, and improving the performance of the spring 103. The two springs 103 on the outer surface of the slide bar 400 are both in a compressed state. Since the springs 103 are in a compressed state, when the mass block 104 vibrates, the springs 103 can quickly play a buffering and vibration reduction role, shortening the deformation of the spring 103.
[0030] The working principle of the utility model is as follows:
[0031] When vibration occurs, the mass block 104 shakes up and down. When the mass block 104 vibrates downward, the second tooth plate 202 drives the large gear 204 to rotate clockwise. Through the transmission action of the large gear 204 and the small gear 203, the first tooth plate 201 is driven to move downward, so that the movable plate 102 moves downward, and the upper spring 103 is stretched and the lower spring 103 is compressed. When the mass block 104 vibrates upward, the second tooth plate 202 drives the large gear 204 to rotate counterclockwise, so the upper spring 103 is compressed and the lower spring 103 is stretched through the first tooth plate 201. Therefore, the stiffness coefficient of the end of the spring 103 is amplified and the static deformation of the end of the spring 103 is shortened through gear transmission, thereby effectively reducing the manufacturing deviation of the tuned mass damper and improving the vibration reduction effect on the bridge. In addition, one of the springs 103 on the upper and lower sides is compressed and the other is stretched. The interaction between the two can make the mass block 104 quickly stabilize, thereby further improving the vibration reduction effect on the bridge.
[0032] The above-mentioned embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of rights of the present invention. Therefore, modifications, equivalent changes, improvements, etc. made according to the scope of the patent application of the present invention are still within the scope covered by the present invention.
Claims
1. A novel low-frequency tuned mass damper, comprising a U-shaped seat (100), a mass block (104) and a damping shock absorber (105), characterized in that: Top plates (101) are installed at both ends of the U-shaped seat (100); two movable plates (102) parallel to each other are arranged on both sides of the interior of the U-shaped seat (100); springs (103) are arranged on opposite surfaces of both ends of the two movable plates (102) in the length direction; the mass block (104) is arranged inside the U-shaped seat (100) and between the movable plates (102) on both sides; the damping shock absorber (105) is installed inside the U-shaped seat (100), and the end of the telescopic end of the damping shock absorber (105) is connected to the lower surface of the mass block (104); gear transmission mechanisms (200) are arranged between the outer surfaces of both sides of the mass block (104) and the movable plates (102) on both sides, and the gear transmission mechanisms (200) are used to shorten the static deformation of the spring (103).
2. A novel low frequency tuned mass damper according to claim 1, characterized in that: The gear transmission mechanism (200) comprises a first tooth plate (201) mounted on the outer surfaces of the two movable plates (102); a second tooth plate (202) is mounted on the side surface of the mass block (104); a pinion (203) and a large gear (204) are arranged between the second tooth plate (202) and the first tooth plate (201); the pinion (203) is meshedly connected to the large gear (204); the pinion (203) is meshedly connected to the first tooth plate (201); and the second tooth plate (202) is meshedly connected to the large gear (204).
3. A novel low frequency tuned mass damper according to claim 2, characterized in that: Two side plates (300) are installed on the inner walls of both sides of the U-shaped seat (100), and a first rotating shaft (301) and a second rotating shaft (302) are rotatably installed between the two side plates (300), the small gear (203) is installed on the outer surface of the first rotating shaft (301), and the large gear (204) is installed on the outer surface of the second rotating shaft (302).
4. A novel low frequency tuned mass damper according to claim 3, characterized in that: Two sliding rods (400) are connected between the U-shaped seat (100) and the top plate (101), and the spring (103) is sleeved on the outer surface of the sliding rod (400). Linear bearings (401) are installed at both ends of the movable plate (102) in the length direction, and the linear bearings (401) are slidably installed on the outer surface of the sliding rod (400).
5. A novel low frequency tuned mass damper according to claim 4, characterized in that: The two springs (103) on the outer surface of the sliding rod (400) are both in a compressed state.
6. A novel low frequency tuned mass damper according to claim 1, characterized in that: The number of the damping shock absorbers (105) is four, and the four damping shock absorbers (105) are respectively arranged at the four corners of the lower surface of the mass block (104).