A built-in negative stiffness damping system for in-plane and out-of-plane vibration control of a cable

Abstract

The application relates to the technical field of structural engineering, in particular to a built-in negative stiffness damper system for controlling in-plane and out-of-plane vibration of a cable, which is used for controlling the vibration of a cable body and comprises a stand, a cross beam, a negative stiffness device, a damper and a connecting rod, the cross beam is arranged above the stand, a first hole is arranged at the top end of the stand away from the stand, the damper is arranged on the side of the cross beam away from the stand and is connected with the cable body, the damper is symmetrically arranged along the vertical plane where the cable body is located, and the negative stiffness device is arranged inside the hollow cross beam and is connected with the cable body through the connecting rod. The built-in negative stiffness damper system for controlling in-plane and out-of-plane vibration of the cable can provide negative stiffness and damping effects when the cable vibrates in the in-plane and out-of-plane directions.

Description

Technical Field

[0001] This invention relates to the field of structural engineering technology, and in particular to a built-in negative stiffness damping system for controlling in-plane and out-of-plane vibration of cables. Background Technology

[0002] Cables play a crucial role in long-span cable-stayed bridges, such as cable-stayed bridges, suspension bridges, and through-arch bridges. As bridge spans increase, so do the lengths and numbers of cables used in bridges. For example, the longest cable in the Changtai Yangtze River Highway-Railway Bridge, currently under construction and the world's longest cable-stayed bridge, reaches 630 meters. The longest cable in the Ma'anshan Highway-Railway Yangtze River Bridge, currently under construction and the largest span three-tower cable-stayed bridge, has reached 650 meters, with over 500 cables used in the entire bridge. Cables are slender, have high axial force and stiffness, but low lateral stiffness, making them prone to lateral vibrations, including in-plane (the vertical plane where the cable lies) and out-of-plane (the horizontal plane perpendicular to the cable axis). The fundamental frequencies of these vibrations are low and densely distributed, and the cables themselves have low damping, making them susceptible to various forms and mechanisms of vibration under loads from wind, rain, and vehicles. Vibration of bridge cables can cause discomfort to pedestrians and affect the normal operation of the bridge. Long-term vibration can damage protective structures, including cable sheaths, caps, and waterproof seals, accelerate the corrosion and fatigue of steel wires, and may eventually lead to sudden breakage and failure of the cables, endangering the safety of the entire bridge.

[0003] With the increasing number of cable-stayed structures in service, the continued increase in cable length, the deterioration of wind conditions, and the increasing service life of some bridges, vibration control of cables has become a key challenge in bridge construction and safe operation. Existing long cables are all equipped with dampers to enhance damping and achieve vibration control. Various types of dampers have been applied in cable structure vibration reduction, including viscous shear dampers, viscous dampers, friction dampers, rubber dampers, eddy current dampers, and magnetorheological dampers. The damping effect of these dampers is directly proportional to the ratio of their installation location to the distance from nearby cable anchor points to the total cable length. As cable length increases, the installation location of the damper needs to be raised to meet damping requirements. Furthermore, many current cable-stayed bridges use anchor plates on the beam for cable fastening, further increasing the installation height of the dampers. The installation height of the cable dampers in a cable-stayed-suspension hybrid system bridge in Turkey has exceeded 7 meters. Excessive installation height brings a series of challenges to installation, inspection, and maintenance, and also affects the aesthetics of the bridge. Therefore, developing and improving the damping effect of dampers and overcoming the limitation of damper installation height on damping effect is of great engineering significance.

[0004] Controlling the in-plane and out-of-plane vibrations of cables in engineering structures remains a pressing problem. Existing dampers have been applied, but they suffer from issues such as large installation height and insufficient damping enhancement for long cables. Effective and practical cable damping enhancement technologies are still lacking. Summary of the Invention

[0005] To address the aforementioned problems, the present invention aims to provide a built-in negative stiffness damping system for controlling the vibration inside and outside the cable surface, offering a new solution for controlling the vibration inside and outside the cable surface and effectively reducing the installation height of the damper.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] This invention provides a built-in negative stiffness damping system for controlling the vibration of a cable body (also referred to as "cable" or "rope"), comprising a column, a crossbeam, a negative stiffness device, a damper, and a connecting rod.

[0008] The negative stiffness device is installed inside the hollow crossbeam, which is located above the column. The top of the crossbeam away from the column has a first hole. The damper is located on the side of the crossbeam away from the column and is connected to the cable body. The damper is symmetrically arranged along the vertical plane of the cable body.

[0009] The negative stiffness device includes a first end plate, a second end plate, a first conduit and a second conduit, an amplifying lever, a fixing plate, a compression spring and a guide tube; one end of the first conduit is connected to the first end plate, and the other end is nested outside the second conduit; the end of the second conduit away from the first conduit is connected to one end of the amplifying lever, and the end of the amplifying lever away from the second conduit is connected to the second end plate.

[0010] The fixing plate is disposed at one end of the second conduit near the amplifying lever; the guide tube is sleeved on the first conduit; the compression spring is sleeved on the first and second conduits, with one end connected to the fixing plate and the other end connected to the guide tube; the first end plate and the second end plate are connected to the inner wall of the crossbeam.

[0011] The amplifying lever has a central hole, and the connecting rod passes through the first hole and is connected to the amplifying lever through the central hole. The end of the connecting rod away from the amplifying lever is connected to the cable body.

[0012] In one embodiment of the present invention, the amplifying lever is connected to the second end plate via a ball joint, the first conduit is connected to the first end plate via a hinge, the second conduit is connected to the amplifying lever via a ball joint, and the amplifying lever is connected to the second end plate via a ball joint.

[0013] In this invention, when the cable body is not vibrating, the central axis of the connecting rod along its length is perpendicular to the central axis of the amplifying lever along its length.

[0014] When the main cable vibrates vertically (in-plane) and horizontally (out-of-plane) in a direction perpendicular to the vertical plane of the cable under the action of dynamic loads such as wind, the connecting rod drives the amplifying lever to rotate around the ball joint on the second end plate. At the same time, the compression spring rotates around the ball joint on the first end plate. The preload inside the compression spring generates a thrust perpendicular to the axis of the crossbeam, which generates a force to push the main cable to continue moving, thus achieving a negative stiffness effect.

[0015] When the cable body vibrates in-plane or out-of-plane, it causes the damper to elongate or compress, generating damping force.

[0016] In this invention, the negative stiffness device is installed inside the crossbeam supporting the damper, forming an integral unit; the negative stiffness device and the damper form a parallel system, which enhances the damping of the overall vibration of the cable and realizes vibration control.

[0017] In one embodiment of the present invention, when the guide tube is close to the fixed plate, the spring is compressed; the length and initial pressure of the spring can be adjusted by adjusting the distance between the first end plate and the second end plate.

[0018] In one embodiment of the present invention, a cable clamp is provided on the outer surface of the cable body, the cable clamp including two half-clips, the two half-clips being fixed by a bolt kit.

[0019] In one embodiment of the present invention, the damper is connected to the half-cable clamp via a ball joint; the connecting rod is connected to the half-cable clamp via a ball joint; and the damper is connected to the crossbeam via a ball joint.

[0020] In one embodiment of the present invention, the outer surface of the first end plate is provided with a first thread; at the connection between the crossbeam and the first end plate, the inner wall is provided with a second thread that matches the first thread.

[0021] In one embodiment of the present invention, the first end plate is screwed into the crossbeam and fixedly connected to the crossbeam by means of a first thread and a second thread engaging.

[0022] In one embodiment of the present invention, a limiting rubber ring is further provided inside the crossbeam, the outer surface of the limiting rubber ring being connected to the inner wall of the crossbeam and sleeved on the outside of the fixing plate;

[0023] The limiting rubber ring is used to restrict the displacement of the fixing plate in the direction perpendicular to its axis.

[0024] In one embodiment of the present invention, the central axis of the crossbeam along its length is perpendicular to the central axis of the column along its height and perpendicular to the vertical plane where the cable body is located.

[0025] In one embodiment of the present invention, the bottom of the column is fixedly connected to the main beam of the bridge or other structure to support the crossbeam.

[0026] In one embodiment of the present invention, the damper is selected from one of a viscous damper, a viscous shear damper, or a friction damper.

[0027] In one embodiment of the present invention, the central axis of the damper is perpendicular to the central axis of the cable body, and the angle between the damper and the vertical plane in which the cable body is located is 10° to 80°.

[0028] In one embodiment of the present invention, the stiffness coefficient k of the negative stiffness device is [not specified] when the cable vibrates in the in-plane. ns (Unit: N / m) Approximately determined by the following formula

[0029]

[0030] Where f0 is the initial pressure of the compression spring (unit: N), l s l is the length of the compression spring in its initial position (in meters), l is the length of the amplifying lever (in meters), and l1 is the distance between the connection point of the connecting rod and the amplifying lever and the connection point of the amplifying lever and the second end plate (in meters).

[0031] When the stiffness coefficient of the connecting rod is k, the negative stiffness coefficient of the negative stiffness device for in-plane vibration of the cable is:

[0032]

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] (1) The present invention proposes a built-in negative stiffness damping system for controlling in-plane and out-of-plane vibration of a cable. When the cable vibrates in both in-plane and out-of-plane directions, it provides negative stiffness and damping effect. Compared with the existing damper scheme, the damping effect is improved by negative stiffness, or the installation height of the damper is reduced when a given damping requirement is met.

[0035] (2) The negative stiffness device in the built-in negative stiffness damping system for controlling the vibration inside and outside the cable surface proposed in this invention is set inside the existing damper support beam and forms an integral part with the damper system, which has good aesthetics.

[0036] (3) The present invention proposes a built-in negative stiffness damping system for controlling the vibration inside and outside of the cable surface. The initial length of the compression spring can be adjusted by screwing in or out the first end plate to meet the vibration control requirements of different cables or cables at different stages of installation and use. Attached Figure Description

[0037] Figure 1 A front view of a built-in negative stiffness damping system for controlling in-plane and out-of-plane vibration of a cable;

[0038] Figure 2 A side view of a built-in negative stiffness damping system for controlling in- and out-of-plane vibration of a cable;

[0039] Figure 3 A mechanical analysis diagram of a negative stiffness device in a built-in negative stiffness damping system for controlling the in-plane and out-of-plane vibration of a cable (the cable is not vibrating);

[0040] Figure 4 A mechanical analysis diagram of a negative stiffness device in a built-in negative stiffness damping system for controlling the in-plane and out-of-plane vibration of a cable (the cable is vibrating);

[0041] Figure 5 This is a damping analysis model of a cable with a built-in negative stiffness damping system for controlling the in-plane and out-of-plane vibrations of a cable, and the cable as a whole.

[0042] Figure 6 The cable damping improvement effect before and after using this technology in Example 1;

[0043] The following are the labels in the diagram: 1. Column; 2. Horizontal beam; 3. Damper; 4. Connecting rod; 5. Cable body; 6. First end plate; 7. Second end plate; 8. First guide tube; 9. Second guide tube; 10. Enlarging lever; 11. Fixing plate; 12. Guide tube; 13. Compression spring; 14. Limiting rubber ring; 15. Half cable clamp; 16. Bolt kit; 17. First hole; 18. Intermediate hole. Detailed Implementation

[0044] This invention provides a built-in negative stiffness damping system for controlling the vibration of a cable's inner and outer surfaces. The system comprises a column, a crossbeam, a negative stiffness device, a damper, and a connecting rod.

[0045] The negative stiffness device is installed inside the hollow crossbeam, which is located above the column. The top of the crossbeam away from the column has a first hole. The damper is located on the side of the crossbeam away from the column and is connected to the cable body. The damper is symmetrically arranged along the vertical plane of the cable body.

[0046] The negative stiffness device includes a first end plate, a second end plate, a first conduit and a second conduit, an amplifying lever, a fixing plate, a compression spring and a guide tube; one end of the first conduit is connected to the first end plate, and the other end is nested outside the second conduit; the end of the second conduit away from the first conduit is connected to one end of the amplifying lever, and the end of the amplifying lever away from the second conduit is connected to the second end plate.

[0047] The fixing plate is disposed at one end of the second conduit near the amplifying lever; the guide tube is sleeved on the first conduit; the compression spring is sleeved on the first and second conduits, with one end connected to the fixing plate and the other end connected to the guide tube; the first end plate and the second end plate are connected to the inner wall of the crossbeam.

[0048] The amplifying lever has a central hole, and the connecting rod passes through the first hole and is connected to the amplifying lever through the central hole. The end of the connecting rod away from the amplifying lever is connected to the cable body.

[0049] In one embodiment of the present invention, the amplifying lever is connected to the second end plate via a ball joint, the first conduit is connected to the first end plate via a hinge, the second conduit is connected to the amplifying lever via a ball joint, and the amplifying lever is connected to the second end plate via a ball joint.

[0050] In this invention, when the cable body is not vibrating, the central axis of the connecting rod along its length is perpendicular to the central axis of the amplifying lever along its length.

[0051] When the main cable vibrates vertically (in-plane) and horizontally (out-of-plane) in a direction perpendicular to the vertical plane of the cable under the action of dynamic loads such as wind, the connecting rod drives the amplifying lever to rotate around the ball joint on the second end plate. At the same time, the compression spring rotates around the ball joint on the first end plate. The preload inside the compression spring generates a thrust perpendicular to the axis of the crossbeam, which generates a force to push the main cable to continue moving, thus achieving a negative stiffness effect.

[0052] When the cable body vibrates in-plane or out-of-plane, it causes the damper to elongate or compress, generating damping force.

[0053] In this invention, the negative stiffness device is installed inside the crossbeam supporting the damper, forming an integral unit; the negative stiffness device and the damper form a parallel system, which enhances the damping of the overall vibration of the cable and realizes vibration control.

[0054] In one embodiment of the present invention, when the guide tube is close to the fixed plate, the spring is compressed; the length and initial pressure of the spring can be adjusted by adjusting the distance between the first end plate and the second end plate.

[0055] In one embodiment of the present invention, a cable clamp is provided on the outer surface of the cable body, the cable clamp including two half-clips, the two half-clips being fixed by a bolt kit.

[0056] In one embodiment of the present invention, the damper is connected to the half-cable clamp via a ball joint; the connecting rod is connected to the half-cable clamp via a ball joint; and the damper is connected to the crossbeam via a ball joint.

[0057] In one embodiment of the present invention, the outer surface of the first end plate is provided with a first thread; at the connection between the crossbeam and the first end plate, the inner wall is provided with a second thread that matches the first thread.

[0058] In one embodiment of the present invention, the first end plate is screwed into the crossbeam and fixedly connected to the crossbeam by means of a first thread and a second thread engaging.

[0059] In one embodiment of the present invention, a limiting rubber ring is further provided inside the crossbeam, the outer surface of the limiting rubber ring being connected to the inner wall of the crossbeam and sleeved on the outside of the fixing plate;

[0060] The limiting rubber ring is used to restrict the displacement of the fixing plate in the direction perpendicular to its axis.

[0061] In one embodiment of the present invention, the central axis of the crossbeam along its length is perpendicular to the central axis of the column along its height and perpendicular to the vertical plane where the cable body is located.

[0062] In one embodiment of the present invention, the bottom of the column is fixedly connected to the main beam of the bridge or other structure to support the crossbeam.

[0063] In one embodiment of the present invention, the damper is selected from one of the following: a viscous damper, a viscous shear damper, or a friction damper.

[0064] In one embodiment of the present invention, the central axis of the damper is perpendicular to the central axis of the cable body, and the angle between the damper and the vertical plane in which the cable body is located is 10° to 80°.

[0065] In one embodiment of the present invention, the stiffness coefficient k of the negative stiffness device is [not specified] when the cable vibrates in the in-plane. ns (Unit: N / m) Approximately determined by the following formula

[0066]

[0067] Where f0 is the initial pressure of the compression spring (unit: N), l s l is the length of the compression spring in its initial position (in meters), l is the length of the amplifying lever (in meters), and l1 is the distance between the connection point of the connecting rod and the amplifying lever and the connection point of the amplifying lever and the second end plate (in meters).

[0068] When the stiffness coefficient of the connecting rod is k, the negative stiffness coefficient of the negative stiffness device for in-plane vibration of the cable is:

[0069]

[0070] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0071] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0072] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0073] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0074] Example 1

[0075] This embodiment provides a built-in negative stiffness damping system for controlling the vibration inside and outside the cable surface, used to control the vibration of the cable body 5, such as... Figure 1-2 As shown, it includes a column 1, a crossbeam 2, a negative stiffness device, a damper 3, and a connecting rod 4.

[0076] The crossbeam 2 is located above the column 1, and the top of the crossbeam away from the column 1 is provided with the first hole 17. The damper 3 is located on the side of the crossbeam 2 away from the column 1 and is connected to the cable body 5. The damper 3 is symmetrically arranged along the vertical plane where the cable body 5 is located.

[0077] The negative stiffness device is installed inside the hollow crossbeam 2 and includes a first end plate 6, a second end plate 7, a first conduit 8, a second conduit 9, an amplifying lever 10, a fixing plate 11, a guide tube 12, and a compression spring 13. One end of the first conduit 8 is connected to the first end plate 6 via a ball joint, and the other end is nested outside the second conduit 9. The end of the second conduit 9 away from the first conduit 8 is connected to one end of the amplifying lever 10 via a ball joint, and the end of the amplifying lever 10 away from the second conduit 9 is connected to the second end plate 7 via a ball joint. The fixing plate 11 is located at one end of the second conduit 9 near the amplifying lever 10. The guide tube 12 is sleeved on the first conduit 8. The compression spring 13 is sleeved on the first conduit 8 and the second conduit 9, with one end connected to the fixing plate 11 and the other end connected to the guide tube 12. The tube 12 is connected; the first end plate 6 and the second end plate 7 are connected to the inner wall of the crossbeam 2; the outer surface of the first end plate 6 is provided with a first thread; at the connection between the crossbeam 2 and the first end plate 6, the inner wall is provided with a second thread that matches the first thread; the first end plate 6 is screwed into the crossbeam 2 and fixedly connected to the crossbeam 2 by the cooperation of the first thread and the second thread; a limiting rubber ring 14 is also provided in the crossbeam 2 to limit the displacement of the fixed plate 11 in the direction perpendicular to its axis, the outer surface of the limiting rubber ring 14 is connected to the inner wall of the crossbeam 2 and is sleeved on the outside of the fixed plate 11; the amplifying lever 10 is provided with a middle hole 18, the connecting rod 4 passes through the first hole 17 and is connected to the amplifying lever 10 through the middle hole 18, and the end of the connecting rod 4 away from the amplifying lever 10 is connected to the cable body 5 through a ball joint.

[0078] The cable body 5 has a cable clamp on its outer surface. The cable clamp includes two half-clips 15, which are fixed by bolt kits 16. The damper 3 is connected to the half-clips 15 by ball joints. The connecting rod 4 is connected to the half-clips 15 by ball joints. The damper 3 is connected to the crossbeam 2 by ball joints.

[0079] The central axis of the crossbeam 2 along its length is perpendicular to the central axis of the column 1 along its height and perpendicular to the vertical plane where the cable body 5 is located; the bottom of the column 1 is fixedly connected to the main beam of the bridge or other structures to support the crossbeam 2; the damper 3 is selected from one of the following: viscous damper, viscous shear damper or friction damper; the central axis of the damper 3 is perpendicular to the central axis of the cable body 5 and the angle between the damper 3 and the vertical plane where the cable body 5 is located is 10°-80°.

[0080] In this embodiment, the negative stiffness device is installed inside the crossbeam 2 supporting the damper 3, forming an integral unit; the negative stiffness device and the damper 3 form a parallel system to enhance the damping of the overall vibration of the cable and realize vibration control; when the guide tube 12 is close to the fixed plate 11, the compression spring 13 is compressed; by adjusting the distance between the first end plate 6 and the second end plate 7, the length and initial pressure of the compression spring 13 can be adjusted.

[0081] When the cable body 5 is not vibrating, the central axis of the connecting rod 4 along its length is perpendicular to the central axis of the amplifying lever 10 along its length.

[0082] When the cable body 5 vibrates vertically (in-plane) and horizontally (out-of-plane) in a direction perpendicular to the vertical plane where the cable body 5 is located under the action of dynamic loads such as wind, the connecting rod 4 drives the amplifying lever 10 to rotate around the ball joint on the second end plate 7. At the same time, the compression spring 13 rotates around the ball joint on the first end plate 6. The preload inside the compression spring 13 generates a thrust perpendicular to the axis of the crossbeam 2, which generates a force to push the cable body 5 to continue moving, thus achieving a negative stiffness effect.

[0083] When the cable body 5 experiences in-plane and out-of-plane vibrations, it causes the damper 3 to extend or compress, generating damping force.

[0084] like Figure 3 As shown, in the initial installation position (without cable vibration), f0 is the initial pressure (in N) of the compression spring 13, l s l is the length of the compression spring 13 in its initial position (in meters), l is the length of the amplifying lever 10 (in meters), and l1 is the distance between the connection point of the connecting rod 4 and the connection point of the amplifying lever 10 and the connection point of the amplifying lever 10 and the second end plate 7 (in meters).

[0085] When the cable vibrates, the connecting rod 4 causes the amplifying lever 10 to deviate from its initial position. At this time, the force balance of the negative stiffness device is as follows: Figure 4 As shown. When the cable body 5 vibrates in the plane and the connecting rod 4 is rigid, the stiffness coefficient k of the negative stiffness device is... ns (Unit: N / m) Approximately determined by the following formula:

[0086]

[0087] When the stiffness coefficient of the connecting rod 4 is k, the negative stiffness coefficient of the device for in-plane vibration is:

[0088]

[0089] Design the dimensions of the negative stiffness device according to Table 1 below, considering that the stiffness of connecting rod 4 is infinite.

[0090] Table 1 shows the negative stiffness device coefficients in the embodiments.

[0091]

[0092] The cable parameters considered in this embodiment are shown in Table 2.

[0093] Table 2 Cable parameters in the embodiments

[0094]

[0095] Damper 3 can be equivalently represented as a viscous unit (viscosity coefficient c) without loss of generality. d ) and a spring element (stiffness coefficient k) d The parallel structure, for the cable-mounted in-plane and out-of-plane vibration control built-in negative stiffness damping system provided in this embodiment, also requires a spring unit with negative stiffness connected in parallel. The mathematical model of the cable after installing the vibration reduction system of this embodiment is as follows: Figure 5 As shown. The nth-order vibration damping of the cable can be calculated using the following formula:

[0096]

[0097] in,

[0098]

[0099]

[0100]

[0101]

[0102] Based on the negative stiffness device coefficients shown in Table 1 and the cable parameters in Table 2, the above formula can be used to analyze and adjust the damper 3 coefficient to determine the maximum value achievable for any first-order modal damping ratio of the cable. In this embodiment, a viscous damper 3 is considered, whose stiffness can be neglected, i.e., k d =0. Figure 6 Table 2 shows the curves of the first-order modal damping ratio of the cable as a function of the equivalent damping coefficient. It can be seen that with traditional damping technology (without negative stiffness effect), the maximum modal damping ratio is 0.011 when damper 3 is installed at 2.25%. However, with this embodiment (negative stiffness coefficient of -178560 N / m), the maximum modal damping ratio is 0.0156, an increase of 41%. Correspondingly, to achieve the same damping ratio (0.011), the installation distance of damper 3 in this embodiment can be significantly reduced to approximately 1.8%, a reduction of 20%.

[0103] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the interpretation of the present invention, without departing from the scope of the invention, should be within the protection scope of the present invention.

Claims

1. A built-in negative stiffness damping system for controlling the vibration of a cable body (5) with and without surface vibration, characterized in that, It includes columns (1), beams (2), negative stiffness devices, dampers (3), and connecting rods (4). The negative stiffness device is installed inside the hollow crossbeam (2). The crossbeam (2) is located above the column (1). The top of the crossbeam away from the column (1) has a first hole (17). The damper (3) is located on the side of the crossbeam (2) away from the column (1) and is connected to the cable body (5). The damper (3) is symmetrically arranged along the vertical plane where the cable body (5) is located. The negative stiffness device includes a first end plate (6), a second end plate (7), a first conduit (8) and a second conduit (9), an amplifying lever (10), a fixing plate (11), a compression spring (13) and a guide tube (12); one end of the first conduit (8) is movably connected to the first end plate (6), and the other end is nested outside the second conduit (9); the end of the second conduit (9) away from the first conduit (8) is movably connected to one end of the amplifying lever (10); the end of the amplifying lever (10) away from the second conduit (9) is movably connected to the second end plate (7); The fixing plate (11) is located at one end of the second conduit (9) near the amplifying lever (10). The guide tube (12) is sleeved on the first conduit (8). The compression spring (13) is sleeved on the first conduit (8) and the second conduit (9), with one end connected to the fixing plate (11) and the other end connected to the guide tube (12). The first end plate (6) and the second end plate (7) are connected to the inner wall of the crossbeam (2). The amplifying lever (10) is provided with a central hole (18). The connecting rod (4) passes through the first hole (17) and is connected to the amplifying lever (10) through the central hole (18). The end of the connecting rod (4) away from the amplifying lever (10) is connected to the cable body (5).

2. The built-in negative stiffness damping system for controlling in-situ vibration of a cable as described in claim 1, characterized in that, The outer surface of the cable body (5) is provided with a cable clamp, which includes two half cable clamps (15), and the two half cable clamps (15) are fixed by a bolt kit (16).

3. The built-in negative stiffness damping system for controlling in-situ vibration of a cable as described in claim 2, characterized in that, The damper (3) is connected to the half cable clamp (15) by a ball joint; the connecting rod (4) is connected to the half cable clamp (15) by a ball joint; the damper (3) is connected to the crossbeam (2) by a ball joint.

4. The built-in negative stiffness damping system for controlling in-situ vibration of a cable as described in claim 1, characterized in that, The outer surface of the first end plate (6) is provided with a first thread; at the connection between the crossbeam (2) and the first end plate (6), the inner wall is provided with a second thread that matches the first thread.

5. The built-in negative stiffness damping system for controlling in-situ vibration of a cable as described in claim 1, characterized in that, The first end plate (6) is connected to the first conduit (8) by a ball joint.

6. The built-in negative stiffness damping system for controlling in-situ vibration of a cable as described in claim 1, characterized in that, The second conduit (9) is connected to the amplifying lever (10) via a ball joint; the amplifying lever (10) is connected to the second end plate (7) via a ball joint.

7. The built-in negative stiffness damping system for controlling in-situ vibration of a cable as described in claim 1, characterized in that, The crossbeam (2) is also provided with a limiting rubber ring (14), the outer surface of which is connected to the inner wall of the crossbeam (2) and is sleeved on the outside of the fixing plate (11); The limiting rubber ring (14) is used to limit the displacement of the fixing plate (11) in the direction perpendicular to its axis.

8. The built-in negative stiffness damping system for controlling in-situ vibration of a cable as described in claim 1, characterized in that, The central axis of the beam (2) along its length is perpendicular to the central axis of the column (1) along its height, and is perpendicular to the vertical plane where the cable body (5) is located.

9. The built-in negative stiffness damping system for controlling in-situ vibration of a cable as described in claim 1, characterized in that, The damper (3) is selected from one of the following: viscous damper, viscous shear damper, or friction damper.

10. The built-in negative stiffness damping system for controlling in-situ vibration of a cable as described in claim 1, characterized in that, The central axis of the damper (3) is perpendicular to the central axis of the cable body (5), and the angle between the damper (3) and the vertical plane where the cable body (5) is located is 10° to 80°.

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