Viscoelasticity-tuned mass damping shock absorber suitable for double-sling vibration control

Abstract

The invention discloses a viscoelasticity-tuned mass damping shock absorber suitable for double-sling vibration control. The viscoelasticity-tuned mass damping shock absorber comprises a viscoelasticity-tuned mass damping element, a rigid cable clamp and a connecting rod. The viscoelasticity-tuned mass damping element comprises a viscoelasticity damping element, a tuned mass shell and a spring; the viscoelastic damping element is arranged in an inner cavity of the tuned mass shell, the two ends of the viscoelastic damping element are each provided with a connecting rod, and meanwhile a set of springs are arranged between the two ends of the viscoelastic damping element and the inner wall of the tuned mass shell. The end of the connecting rod extends out of the tuned mass shell, and the tuned mass shell is filled with damping oil. Therefore, a viscoelastic damping system and a tuned mass damping system are combined, a good wind vibration control effect on relative movement and overall movement between the double slings is achieved, the viscoelastic damping element is convenient to manufacture and replace, the stability of the oil damping system is high, and the applicability of the damper is improved.

Description

Technical Field

[0001] The invention belongs to the field of bridge engineering, in particular to a double-cable structure of a bridge, and specifically to a viscoelastic-tuned mass damping shock absorber suitable for double-cable vibration control. Background Art

[0002] In the field of long-span bridge design, suspension bridges have become the mainstream structural choice with their elegant light structure and excellent spanning capacity, especially the feat of being able to easily achieve a span of a kilometer. Globally, the top ten spans of long-span bridges are all occupied by suspension bridges. As suspension bridges continue to challenge longer distances, the length of the cables has also increased, and some have exceeded the 200-meter mark.

[0003] However, as a typical flexible structure, long cables are easily affected by strong winds, which can cause large-scale high-frequency vibrations. Such harmful vibrations not only accelerate structural fatigue, but also easily cause public concerns about bridge safety. Therefore, effective control and protection of cable vibrations is an important part of ensuring the safe operation of bridges.

[0004] The types of cables for suspension bridges mainly include single cable strand, double cable strand and multiple cable strands. The double cable structure is more widely used in practical applications. However, due to the mutual influence between the two cables, the double cable structure is prone to aerodynamic effects between the cables, resulting in wake-induced vibration, which is also another concern for cable vibration control. In the double cable structure, not only should large amplitude and high frequency vibration be prevented, but also the problem of cable collision between the double cables should be absolutely avoided.

[0005] For the vibration prevention of the existing double-cable structure, there are conventional facilities such as vibration-damping frames and viscous dampers, but these facilities are not effective in preventing and controlling the overall multi-modal vibration, and can only control the relative movement between the two cables. However, the double-cable structure not only has the problem of relative movement, but also faces large overall vibration, both of which have an adverse effect on the structure. Therefore, how to effectively control the relative and overall vibration in the double-cable structure has become the focus of current research on cable vibration control, which has important application value and engineering significance.

[0006] In addition, the cost, manufacturing method and implementation process of the damper are key factors in selecting an appropriate vibration control method. More importantly, the durability, applicability and economical maintenance and replacement of the vibration control system are also factors that designers and bridge users need to consider. Summary of the invention

[0007] In view of the shortcomings of existing dampers in controlling double-cable vibrations, the purpose of the present invention is to provide a viscoelastic-tuned mass damping vibration absorber suitable for double-cable vibration control, so as to solve the problems of existing dampers such as limited frequency control range, limited damping improvement, difficulty in controlling overall vibration, and difficulty in maintenance and replacement.

[0008] In order to achieve the above-mentioned actual sling vibration control, the technical solution adopted by the present invention is as follows:

[0009] A viscoelastic-tuned mass damping vibration absorber suitable for double-cable vibration control is arranged between double-cable structures; it includes a viscoelastic-tuned mass damping element and a connecting rod; wherein:

[0010] The viscoelastic-tuned mass damping element comprises a viscoelastic damping element, a tuned mass housing and a spring;

[0011] The viscoelastic damping element is arranged in the inner cavity of the tuned mass housing, and a connecting rod is respectively installed at both ends of the viscoelastic damping element, and a group of springs are arranged between both ends of the viscoelastic damping element and the inner wall of the tuned mass housing, the springs are sleeved on the periphery of the connecting rod, and the elastic expansion and contraction direction of the springs is parallel to the length extension direction of the connecting rod;

[0012] The end of the connecting rod extends out of the tuning mass housing, and the connecting rod and the tuning mass housing are sealed and connected, and the tuning mass housing is filled with damping oil;

[0013] The end of the connecting rod extending out of the tuning mass housing can be connected and fixed to the double sling structure.

[0014] Preferably, both ends of the viscoelastic damping element are each equipped with a connecting rod through an element fixture; and the spring is arranged between the element fixture and the inner wall of the tuning mass housing.

[0015] Preferably, the component fixture is a special component fixture, which is a two-piece structure, including a base piece and a pressing piece;

[0016] The compression plate is an annular plate, and the inner ring of the compression plate is arranged in a convex groove shape, and the compression plate is provided with a circle of bolt holes A along the circumference;

[0017] The base plate is in a T shape as a whole, including a vertical section and a horizontal section arranged in the middle of the vertical section. A connecting hole b (4-3) is arranged through the middle of the horizontal section, and a circle of bolt holes B is arranged along the circumference of the vertical section.

[0018] The viscoelastic damping element is cylindrical with flanges at both ends, and the shape of the flange end of the viscoelastic damping element matches the shape of the inner ring of the compression plate, so that the flange end of the viscoelastic damping element bites into the inner ring of the compression plate;

[0019] The base plate is sleeved on the connecting rod through the connecting hole b, and the vertical section of the base plate is tightly attached to the clamping plate. At the same time, the bolt holes B and bolt holes A of the base plate are arranged one by one; a part of each correspondingly arranged bolt hole B and bolt hole A is fastened by bolt fasteners, and the remaining part forms a damping oil hole for the flow of damping oil.

[0020] Preferably, the inner diameter of the tuning mass housing of the shock absorber is larger than the diameter of the special element fixture, balls are arranged between the tuning mass housing and the special element fixture for lubrication when the damper is in working state, and the special element fixture moves freely in the tuning mass housing.

[0021] Preferably, the vibration absorber tuned mass housing is provided with a connecting hole c, in which a linear bearing is embedded, and the connecting rod passes through the connecting hole c via the linear bearing.

[0022] Preferably, the diameter of the connecting channel c is smaller than the outer diameter of the horizontal and vertical sections in the special component fixture.

[0023] Preferably, a buffer pad is provided on the inner side of the connecting channel c.

[0024] Preferably, the connecting rod is fastened to the double sling structure by a rigid cable clamp.

[0025] Preferably, the rigid cable clamp is a two-piece structure, including a first and a second half-piece cable clamp;

[0026] There are fastening holes between the first and second half cable clamps, and the rigid cable clamp and the double sling structure are clamped and fixed by assembling fasteners in each fastening hole;

[0027] The second half cable clamp is arranged close to the tuning mass housing, and a connecting hole a is arranged on the second half cable clamp.

[0028] The beneficial effects of the present invention are:

[0029] The viscoelastic-tuned mass damping vibration isolator of the present invention has the function of controlling the relative and overall vibration of double slings. The viscoelastic damping system controls the relative vibration between the slings, and the tuned mass damping system controls the overall vibration of the slings.

[0030] 1. The viscoelastic-tuned mass damper of the present invention has a displacement limiting function. It provides flexible constraints to control abnormal vibration of the sling under small amplitudes, and constrains the relative displacement between the double slings through the rigid constraints provided by the tuned mass housing under large amplitudes.

[0031] 2. The viscoelastic-tuned mass damping shock absorber of the present invention has an insurance function. It can still provide a certain control effect after the viscoelastic element breaks, which only affects the tensile damping, but can still play a compression damping role. The reason is that after the viscoelastic element breaks, it provides damping during compression, and can restore the original length during stretching due to the elastic characteristics of the material, and continue to provide damping in the next compression.

[0032] 3. The viscoelastic damping element of the present invention controls the damping, mass and elasticity of the damping element by material properties and element size, thereby increasing the damping of the sling vibration process and achieving vibration control of the sling structure.

[0033] 4. The damper of the present invention has low cost, simple manufacturing method and safe and reliable implementation process, the viscoelastic material is easy to process, and the maintenance and replacement are economical. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A schematic diagram of the combination of a viscoelastic-tuned mass damping vibration isolator structure and a double-cable structure for controlling the vibration of the double-cable;

[0035] Figure 2 It is a structural schematic diagram of the cable clamp;

[0036] Figure 3 Schematic diagram of the structure of the base plate in the special component fixture; in the figure: (a) is a cross-sectional view of the base plate, (b) is a left view of (a);

[0037] Figure 4 Schematic diagram of the structure of the clamping plate in the special component fixture; in the figure: (a) is a cross-sectional view of the clamping plate, (b) is a left view of (a);

[0038] Figure 5 is a schematic diagram of the structure of the viscoelastic damping element;

[0039] Figure 6 It is a schematic diagram of the structure of the tuning mass housing;

[0040] The meanings of the serial numbers in the figure are: 1. sling, 2. cable clamp, 2-1. half-piece cable clamp, 2-2. half-piece cable clamp, 2-3. connecting rod connecting hole, 3. connecting rod, 4. special component clamp, 4-1. fixture base plate, 4-2. fixture pressing plate, 4-3. connecting rod connecting hole, 4-4. bolt hole A, 4-5. bolt hole B, 4-6. ball, 5. viscoelastic damping element, 5-1. flange, 6. tuned mass housing, 6-1. connecting rod hole c, 6-2. shock pad, 7. spring. DETAILED DESCRIPTION

[0041] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention but not to limit the scope of the present invention.

[0042] like Figures 1 to 6 As shown, the viscoelastic-tuned mass damping shock absorber suitable for double-cable vibration control of the present invention is arranged between the double-cable structures; it includes a viscoelastic-tuned mass damping element and a connecting rod 3; wherein:

[0043] Viscoelastic-tuned mass damping elements, such as Figure 1 As shown, it includes a viscoelastic damping element 5, a tuning mass housing 6 and a spring 7;

[0044] The viscoelastic damping element 5 is arranged in the inner cavity of the tuned mass housing 6, and a connecting rod 3 is respectively installed at both ends of the viscoelastic damping element 5. At the same time, a group of springs 7 are arranged between the two ends of the viscoelastic damping element 5 and the inner wall of the tuned mass housing 6. The springs 7 are arranged around the periphery of the connecting rod 3, and the elastic expansion and contraction direction of the springs 7 is parallel to the length extension direction of the connecting rod 3.

[0045] In the attached drawings, a connecting rod 3 is mounted at each end of the viscoelastic damping element 5 through a special element fixture 4; a spring 7 is arranged between the special element fixture 4 and the inner wall of the tuning mass housing 6. The inner diameter of the tuning mass housing 6 of the shock absorber is larger than the diameter of the special element fixture 4. Balls 4-6 are arranged between the tuning mass housing 6 and the special element fixture 4, which are lubricated when the damper is in working state, and the special element fixture 4 moves freely in the tuning mass housing 6. When compressed, the special element fixture 4 moves inward, and when the compression reaches the maximum limit, the viscoelastic damping element 5 is axially compressed and radially expanded to fill the entire internal space to limit the maximum compression of the shock absorber.

[0046] like Figure 3 , Figure 4 As shown, the special component fixture 4 is a two-piece structure, including a base piece 4-1 and a pressing piece 4-2;

[0047] like Figure 4 As shown, the pressing plate 4-2 is an annular plate, and the inner ring of the pressing plate 4-2 is arranged in a convex groove shape, and the pressing plate 4-2 is provided with a circle of bolt holes A4-4 along the circumferential direction; Figure 3As shown, the base plate 4-1 is T-shaped as a whole, including a vertical section and a horizontal section arranged in the middle of the vertical section, the horizontal section is provided with a connecting channel b4-3 along the middle position, and the vertical section is provided with a circle of bolt channels B4-5 along the circumferential direction; the viscoelastic damping element 5 is a cylinder with flanges at both ends, and the shape of the flange end of the viscoelastic damping element 5 matches the inner ring shape of the clamping plate 4-2, so that the flange end of the viscoelastic damping element 5 is engaged in the inner ring of the clamping plate 4-2, thereby realizing the flexible connection of the two slings and the relative vibration control between the slings.

[0048] The base plate 4-1 is sleeved on the connecting rod 3 through the connecting hole b and fixed to the connecting rod 3, and the vertical section of the base plate 4-1 is tightly attached to the clamping plate 4-2. At the same time, the bolt holes B4-5 and the bolt holes A4-4 of the base plate 4-1 are arranged one by one; a part of the corresponding bolt holes B4-5 and the bolt holes A4-4 are fastened by bolt fasteners, and the remaining part forms damping oil holes for the flow of damping oil.

[0049] In the present invention, the end of the connecting rod 3 extends out of the tuning mass housing 6, and the connecting rod 3 and the tuning mass housing 6 are sealed and connected, which can effectively prevent the leakage of the damping oil filled in the tuning mass housing 6. Specifically, the tuning mass housing 6 of the shock absorber is provided with a connecting channel c6-1, which is embedded with a linear bearing, and the connecting rod 3 passes through the connecting channel c6-1 through the linear bearing, which effectively ensures that the tuning mass housing 6 slides freely on the connecting rod 3. The diameter of the connecting channel c6-1 is smaller than the outer diameter of the horizontal and vertical sections in the special element fixture 4, so that when the stretching reaches the maximum limit, the damping element fixture 4 collides with the tuning mass housing 6 to limit the maximum stretching amount of the shock absorber.

[0050] In the present invention, a buffer pad 6 - 2 is provided inside the connection channel c6 - 1 to prevent the special component fixture 4 from directly and rigidly colliding with the tuning mass housing 6 when the tuning mass housing 6 is displaced.

[0051] The damping oil is filled in the tuning mass housing 6 of the shock absorber. When relative displacement occurs with the special element fixture 4, the damping oil passes through the damping oil channel 4-3 arranged on the special element fixture to produce a damping effect, forming an oil damping system.

[0052] The present invention can control the distance between the rigid cable clamp 2 and the special element clamp 4 by changing the length of the connecting rod 3, so as to be applicable to double sling structures with different spacings.

[0053] The end of the connecting rod 3 extending out of the tuned mass housing 6 can be connected and fixed to the double sling structure. In the present invention, the connecting rod 3 is fastened to the double sling structure 1 through a rigid cable clamp 2, that is, each sling of the double sling structure 1 is clamped by a rigid cable clamp 2. Figure 2As shown, the rigid cable clamp 2 is a two-piece structure, including a first half-piece cable clamp and a second half-piece cable clamp; there are fastening holes between the first half-piece cable clamp and the second half-piece cable clamp, and the rigid cable clamp 2 and the double sling structure 1 are clamped and fixed by assembling fasteners in each fastening hole; the second half-piece cable clamp is arranged close to the tuned mass housing 6, and the second half-piece cable clamp is provided with a connecting channel a2-3. In addition, the present invention places a certain amount of rubber gaskets between the sling and the rigid cable clamp 2 for friction engagement and appropriate elastic constraint.

[0054] It can be seen that when the viscoelastic-tuned mass damping shock absorber described in the present invention is actually used, two rigid cable clamps are fixed on two cables, and the rigid cable clamps transmit the displacement of the cables to the viscoelastic-tuned mass damping element via the connecting rod 3. The effective device of the viscoelastic-tuned mass damping element is sealed in the tuning mass housing 6; the distance between the rigid cable clamp and the connecting rod is adjustable to meet the double cable structure with different cable spacings; the tuning mass housing 6 seals the viscoelastic damper (i.e., the viscoelastic damping element 5) and the viscoelastic damping fixture (i.e., the special element fixture 4) to isolate them from the external environment, and at the same time acts as a tuning mass block; the viscoelastic damping element is cylindrical in shape, and the material and specifications can be changed; the special element fixture is connected to the tuning mass housing with a spring to form a spring-mass system; the tuning mass housing is filled with damping oil, and the damping of the oil damping system can be adjusted by adjusting the number of oil ports on the special element fixture. Therefore, the viscoelastic-tuned mass damping vibration absorber of the present invention combines the viscoelastic damping system with the tuned mass damping system, and has a good wind vibration control effect on the relative movement and overall movement between the double suspension cables. The viscoelastic damping elements are easy to manufacture and replace, and the oil damping system has strong stability, which increases the applicability of the damper.

[0055] The viscoelastic-tuned mass damping vibration absorber of the present invention specifically includes the following steps during actual installation:

[0056] Step 1: Conduct a thorough on-site investigation, select the slings for vibration control or vibration prevention, determine the geometric parameters and dynamic characteristics of the double sling system, determine the size of the rigid cable clamp and pre-assemble the viscoelastic-tuned mass damper that meets the requirements in the factory;

[0057] Step 2: determine the installation height of the viscoelastic-tuned mass damping shock absorber, install a rigid cable clamp on the double-cable structure, and connect the connecting rod to realize the assembly of the viscoelastic-tuned mass damping shock absorber on the double-cable structure; Step 3: fill the damping oil into the tuning mass housing of the shock absorber.

[0058] In this embodiment, the following aspects should be noted:

[0059] 1. The oil seal between the tuning mass housing and the connecting rod must ensure good sealing to prevent leakage of damping oil;

[0060] 2. The motion resistance between the tuned mass housing and the special component fixture needs to be reduced to ensure a small starting resistance for the tuned mass damping system;

[0061] 3. Clarify the dynamic characteristics of the sling and confirm the system parameters of the viscoelastic damping system and the tuned mass damping system;

[0062] The technical means disclosed in the scheme of the present invention are not limited to the technical means disclosed in the above-mentioned implementation mode, but also include technical schemes composed of any combination of the above technical features.

Claims

1. A viscoelastic-tuned mass damper suitable for double-cable vibration control, arranged between double-cable structures; characterized in that: It comprises a viscoelastic-tuned mass damping element and a connecting rod (3); wherein: The viscoelastic-tuned mass damping element comprises a viscoelastic damping element (5), a tuned mass housing (6) and a spring (7); The viscoelastic damping element (5) is arranged in the inner cavity of the tuning mass housing (6), and a connecting rod (3) is respectively installed at both ends of the viscoelastic damping element (5). Meanwhile, a group of springs (7) are arranged between both ends of the viscoelastic damping element (5) and the inner wall of the tuning mass housing (6), and the springs (7) are sleeved on the periphery of the connecting rod (3), and the elastic expansion and contraction direction of the springs (7) is parallel to the length extension direction of the connecting rod (3); The end of the connecting rod (3) extends out of the tuning mass housing (6), and the connecting rod (3) and the tuning mass housing (6) are sealed and connected, and the tuning mass housing (6) is filled with damping oil; The end of the connecting rod (3) extending out of the tuning mass housing (6) can be connected and fixed to the double sling structure.

2. The viscoelastic-tuned mass damping vibration absorber for double-cable vibration control according to claim 1, characterized in that: Both ends of the viscoelastic damping element (5) are respectively equipped with a connecting rod (3) via an element fixture; a spring (7) is arranged between the element fixture and the inner wall of the tuning mass housing (6).

3. The viscoelastic-tuned mass damping vibration absorber for double-cable vibration control according to claim 2, characterized in that: The component fixture is a special component fixture (4) having a two-piece structure, comprising a base piece (4-1) and a pressing piece (4-2); The pressing plate (4-2) is an annular plate, and the inner ring of the pressing plate (4-2) is arranged in a convex groove shape, and the pressing plate (4-2) is provided with a circle of bolt holes A along the circumference; The base plate (4-1) is in a T-shape as a whole, comprising a vertical section and a horizontal section arranged in the middle of the vertical section, a connecting hole b (4-3) is arranged through the middle of the horizontal section, and a circle of bolt holes B is arranged along the circumference of the vertical section; The viscoelastic damping element (5) is cylindrical with flanges at both ends, and the shape of the flange end of the viscoelastic damping element (5) matches the shape of the inner ring of the compression plate (4-2), so that the flange end of the viscoelastic damping element (5) is engaged in the inner ring of the compression plate (4-2); The base plate (4-1) is sleeved on the connecting rod (3) through the connecting hole b, and the vertical section of the base plate (4-1) is tightly attached to the pressing plate (4-2). At the same time, the bolt holes B and bolt holes A of the base plate (4-1) are arranged one by one in correspondence; a part of each correspondingly arranged bolt hole B and bolt hole A is fastened by a bolt fastener, and the remaining part forms a damping oil hole for the flow of damping oil.

4. The viscoelastic-tuned mass damping vibration absorber for double-cable vibration control according to claim 2, characterized in that: The inner diameter of the tuning mass housing (6) of the vibration damper is greater than the diameter of the special element fixture (4); balls (4-6) are arranged between the tuning mass housing (6) and the special element fixture (4) and are lubricated when the damper is in working condition; the special element fixture (4) moves freely in the tuning mass housing (6).

5. The viscoelastic-tuned mass damping vibration absorber for double-cable vibration control according to claim 2, characterized in that: The vibration absorber tuning mass housing (6) is provided with a connecting hole c (6-1) with a linear bearing embedded therein, and the connecting rod (3) passes through the connecting hole c (6-1) via the linear bearing.

6. The viscoelastic-tuned mass damping vibration absorber for double-cable vibration control according to claim 4, characterized in that: The diameter of the connecting channel c (6-1) is smaller than the outer diameter of the horizontal and vertical sections in the special element fixture (4).

7. The viscoelastic-tuned mass damping vibration absorber for double-cable vibration control according to claim 4, characterized in that: A buffer pad (6-2) is arranged inside the connecting channel c (6-1).

8. The viscoelastic-tuned mass damping vibration absorber for double-cable vibration control according to claim 1, characterized in that: The connecting rod (3) is fastened to the double sling structure (1) via a rigid cable clamp (2).

9. The viscoelastic-tuned mass damping vibration absorber for double-cable vibration control according to claim 7, characterized in that: The rigid cable clamp (2) is a two-piece structure, comprising a first half-piece cable clamp and a second half-piece cable clamp; There are fastening holes that penetrate each other between the first and second half cable clamps, and the rigid cable clamp (2) and the double sling structure (1) are clamped and fixed by assembling fasteners in the fastening holes; The second half cable clamp is arranged close to the tuning mass housing (6), and a connecting hole a (2-3) is arranged on the second half cable clamp; The outer end of the connecting rod (3) is assembled in the connecting channel a (2-3).

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