Liquid-filled rubber damping shock absorber and method suitable for vibration control of double slings of suspension bridge

Abstract

The invention discloses a liquid-filled rubber damping shock absorber and method suitable for vibration control over double slings of a suspension bridge, the shock absorber is connected between the two slings, and the shock absorber comprises an inner side clamp located in the center of the whole shock absorber; the variable-diameter outer side clamp is positioned on the outer side of the inner side clamp; the plurality of liquid-filled rubber damping elements are connected between the inner side clamp and the variable-diameter outer side clamp and are uniformly arranged along the circumferential direction of the inner side clamp; the fastening cable clamp is connected between the sling and the variable-diameter outer side clamp; according to the liquid-filled rubber damping elements, the service performance of the liquid-filled rubber damping elements is adjusted through high-pressure hydraulic oil, the vibration mode damping ratio of the liquid-filled rubber damping elements is controlled to be larger than 0.8%, the multiple liquid-filled rubber damping elements are combined to control the multi-order mode, and effective control over in-plane movement and out-of-plane movement of the double slings is achieved in a circumferential arrangement mode. The shock absorber has a multi-frequency control effect, in-plane and out-of-plane vibration control of a double-sling structure can be achieved at the same time, and economical efficiency is good.

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 liquid-filled rubber damping shock absorber and a method suitable for vibration control of double-cables of a suspension bridge. Background Art

[0002] In the field of long-span bridge design, suspension bridges have become a major structural choice. They are lightweight, beautiful, and can span distances of kilometers, making them popular. In fact, in the global ranking of long-span bridges, the top ten are completely dominated by suspension bridge structures. As the span of suspension bridges continues to increase, the length of the cables continues to grow, and the longest cable has reached more than 200 meters.

[0003] However, long cable structures are typical flexible components, which are prone to large-amplitude vibration and high-frequency vibration under wind loads. Continuous vibration will lead to fatigue damage and cause widespread negative social concern. In order to ensure the safe operation of bridge structures, vibration control and protection of cable structures are crucial and cannot be ignored.

[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 cable collision problem should be absolutely avoided.

[0005] There are also some reports on the vibration control of double cables. Among them, in a vibration control device and method for a suspension bridge cable with patent number ZL201510062295.X, the dampers are arranged in sequence along the length direction of the cable and fixed to the cable by cable clamps. In this implementation scheme, a large number of dampers are used, and the probability of connection fatigue hazards increases. The risk of the damper falling from a high altitude cannot be avoided, which brings safety hazards to driving. Most importantly, this damper can only control in-plane vibrations and lacks effective effect on out-of-plane vibrations. The same shortcomings also appear in other shock absorber schemes, such as the damper provided by patent number ZL201020161536.9. The safety hazards of this multi-point arrangement and the limitation of only being able to achieve in-plane vibration reduction are factors that are often not considered in current suspension cable shock absorber schemes. Patent No. ZL202211734647.8, an array-type tuned mass damper for multi-modal high-frequency vibration control of double slings and its construction method, can control in-plane and out-of-plane vibrations and also has a multi-frequency tuning effect. However, the number of tuned damping elements installed is limited, resulting in a limited control frequency range for this implementation scheme. More importantly, by using tuned mass to control the vibration of the sling, the type of vibration controlled is targeted, and it tends to control high-frequency vortex-induced vibrations.

[0006] For the vibration prevention and control of existing double-cable structures, there are conventional facilities such as vibration-damping frames and viscous dampers, but these facilities have considerable limitations in terms of simultaneous multi-frequency control, in-plane and out-of-plane control, and near-ground layout. However, in actual operation, the double-cable structure has multiple risk factors. Not only does it have an unpredictable frequency range, but it also faces large out-of-plane vibrations. In the safe operation and maintenance of many bridges, there are also mandatory requirements for the installation height of the damper. The superposition of these related factors poses a challenge to the effective vibration reduction of the damper. Therefore, how to effectively control harmful vibrations in double-cable structures has become the focus of current research on cable vibration control, which has important application value and engineering significance.

[0007] In addition, the cost, manufacturing method and implementation process of the damper are key factors in selecting an appropriate vibration control method. In actual operation, 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

[0008] In view of the shortcomings of existing dampers in controlling double-cable vibrations, the purpose of the present invention is to propose a liquid-filled rubber damping shock absorber suitable for controlling double-cable vibrations of suspension bridges, so as to solve the problems of limited frequency control range, limited damping improvement, difficulty in controlling off-surface vibrations, and difficulty in maintenance and replacement of existing dampers.

[0009] In order to achieve the above-mentioned actual sling vibration control, the technical solution adopted by the present invention is as follows: A liquid-filled rubber damping shock absorber suitable for vibration control of double suspension cables of a suspension bridge, connected between the two suspension cables, comprising: The inner clamp is located in the center of the entire shock absorber; A variable diameter outer clamp, located outside the inner clamp; A liquid-filled rubber damping element, comprising a plurality of liquid-filled rubber damping elements connected between the inner clamp and the variable diameter outer clamp, and uniformly arranged along the circumference of the inner clamp; A first fastening cable clamp, one end of which is fixedly connected to the first sling located on one side, and the other end of which has a first damper connecting end, wherein the first damper connecting end is connected to a side of the variable diameter outer clamp adjacent to the first sling; A second fastening cable clamp, one end of which is fixedly connected to the second sling located at the other side, and the other end of which has a second damper connecting end, wherein the second damper connecting end is connected to a side of the variable diameter outer clamp adjacent to the second sling; The service performance of the liquid-filled rubber damping element is adjusted by high-pressure hydraulic oil, and the damping ratio of the vibration mode controlled by the liquid-filled rubber damping element is controlled to be greater than 0.8%. A plurality of liquid-filled rubber damping elements are combined to control multi-order modes, and the in-plane and out-of-plane movement of the double slings are controlled by circumferential arrangement.

[0010] It also includes a protective shell, which covers the inside clamp, the variable diameter outside clamp and the outside of the liquid-filled rubber damping element; A space is left between the inner diameter of the protective shell and the variable diameter outer clamp for the variable diameter outer clamp to change its diameter, and the maximum deformation of the variable diameter outer clamp can be restricted; The protective shell is provided with a cable clamp channel for the first damper connecting end and the second damper connecting end to pass through.

[0011] The liquid-filled rubber damping element comprises a rubber body, the interior of the rubber body is hollow, a self-locking oil filling hole is provided on the rubber body, and hydraulic oil is injected into the internal hollow part through the self-locking oil filling hole.

[0012] The outer wall of the inner clamp is provided with inner fixing channels in the circumferential direction, the number of which is equal to the number of the liquid-filled rubber damping elements; The variable diameter outer clamp is provided with an outer fixing hole corresponding to the inner fixing hole; The liquid-filled rubber damping element is provided with a first groove at one end and a second groove at the other end. When the liquid-filled rubber damping element is injected with pressurized liquid, the liquid-filled rubber damping element can expand, the first groove fully engages with the inner fixed channel on the inner clamp, and the second groove fully engages with the outer fixed channel on the variable diameter outer clamp, thereby realizing a flexible connection between the two slings.

[0013] The first fastening cable clip comprises: Two first semi-annular clamps, the two first semi-annular clamps are fixedly connected by a first square clamping plate group and a fastener, and one of the first semi-annular clamps is connected to the first damper connection end; The second fastening cable clip comprises: Two second semi-annular clamps are fixedly connected by a second square clamp plate group and a fastener, and one of the second semi-annular clamps is connected to the second damper connection end.

[0014] The variable diameter outer clamp comprises: Two arc-shaped clamps, one of which is threadedly connected to the first damper connecting end, and the other arc-shaped clamp is threadedly connected to the second damper connecting end. The distance between the fastening cable clamp and the variable diameter outer clamp is changed by adjusting the threads to adapt to double sling structures with different spacings.

[0015] The arc angle of the arc-shaped clamp is less than π to prevent rigid collision between the two clamps.

[0016] The two ends of the liquid-filled rubber damping element are set to different sizes to adapt to the circumferential arrangement of the liquid-filled rubber damping element in the damper. The larger end of the liquid-filled rubber damping element is connected to the variable diameter outer clamp, and the smaller end of the liquid-filled rubber damping element is connected to the inner clamp.

[0017] The installation method of the liquid-filled rubber damping shock absorber suitable for vibration control of double cables of a suspension bridge comprises the following steps: Step 1: Conduct a thorough on-site investigation, select slings for vibration control or vibration prevention, determine the geometric parameters and dynamic characteristics of the double sling system, and determine the size of the cable clamp; Step 2: Determine the installation height of the liquid-filled rubber damper, install the cable clamp on the double sling, connect the outer protective shell of the shock absorber, and then install the variable diameter outer clamp to control the spacing of the variable diameter outer clamp; Step 3: placing a rubber liquid-filled rubber damping element between the inner clamp and the variable diameter outer clamp, and injecting high-pressure oil into the plurality of rubber liquid-filled rubber damping elements through the self-locking oil injection hole; Step 4: Use a protective shell to cover and seal the inner clamp, the variable diameter outer clamp and the liquid-filled rubber damping element.

[0018] The working method of the liquid-filled rubber damping shock absorber suitable for the vibration control of the double cables of the suspension bridge is to make the dynamic characteristics of the multiple liquid-filled rubber damping elements different by filling different volumes of liquid inside the multiple liquid-filled rubber damping elements, and multiple combinations are used to realize the nonlinear and multi-band vibration control of the damper; Multiple liquid-filled rubber damping elements are arranged along the circumference, and the movement of the sling in each direction can achieve damping energy dissipation, which will simultaneously control the abnormal vibration of the sling in the plane, that is, the span direction, and out of the plane, that is, the vertical span direction; By controlling the liquid pressure inside the liquid-filled rubber damping element, the damping, mass and elasticity of the liquid-filled rubber damping element are controlled, the damping of the sling vibration process is increased, and broadband vibration control of the sling structure is achieved.

[0019] 1. The circumferentially arranged liquid-filled rubber damping shock absorber of the present invention has different liquid filling volumes inside the liquid-filled rubber damping elements, resulting in different dynamic characteristics of each liquid-filled rubber damping element. Various combinations can achieve nonlinear and multi-band vibration control of the damper.

[0020] 2. The circumferentially arranged liquid-filled rubber damping shock absorber of the present invention has liquid-filled rubber damping elements arranged circumferentially, and the movement in each direction can realize damping energy dissipation, which will simultaneously control the abnormal vibration of the sling in the plane, that is, the span direction, and out of the plane, that is, the vertical span direction.

[0021] 3. The liquid-filled rubber damping element of the present invention controls the damping, mass and elasticity of the damping element by the pressure of the internal liquid, thereby increasing the damping of the sling vibration process and achieving broadband vibration control of the sling structure.

[0022] 4. The damper of the present invention has low cost, simple manufacturing method and safe and reliable implementation process, the rubber material is easy to process, and the maintenance and replacement are economical. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the combination of the liquid-filled rubber damping shock absorber structure and the double-cable structure suitable for the vibration control of the double-cable of the suspension bridge of the present invention; Figure 2 The overall appearance of the rubber damping shock absorber with a protective shell; Figure 3 To fasten the cable clip; Figure 4 It is a variable diameter outer clamp; Figure 5 For the inner clamp; Figure 6 It is a liquid-filled rubber damping element; Figure 7 is the cross section of the liquid-filled rubber damping element; Among them: 1. sling, 2. fastening cable clamp, 2-1. square clamp, 2-2. bolt hole, 3. protective shell, 3-1. cable clamp channel, 4. variable diameter outer clamp, 4-1. outer fixed channel, 4-2. cable clamp connecting channel, 5. liquid-filled rubber damping element, 5-1. groove, 5-2. self-locking oil filling hole, 5-3. high-pressure hydraulic oil, 6. inner clamp, 6-1. inner fixed channel. DETAILED DESCRIPTION

[0024] 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.

[0025] like Figure 1 As shown, a liquid-filled rubber damping shock absorber suitable for vibration control of double cables of a suspension bridge in this embodiment includes a fastening cable clamp 2, a protective shell 3, a variable diameter outer clamp 4, a liquid-filled rubber damping element 5 and an inner clamp 6.

[0026] Each sling 1 of the double sling structure described in this embodiment is clamped by a fastening cable clamp 2, and the fastening cable clamp 2 fastens and clamps the sling 1 through the bolts in the bolt holes 2-2, and a certain amount of rubber gaskets are placed between the sling 1 and the fastening cable clamp 2 for friction engagement and appropriate elastic constraint.

[0027] The fastening cable clamp 2 described in this embodiment has a damper connecting end, which passes through the cable clamp channel 3-1 opened on the protective shell 3 and is connected to the variable diameter outer clamp. The surfaces of the fastening cable clamp 2 and the cable clamp channel 3-1 are smooth and are lubricated when the damper is in working state to ensure that the fastening cable clamp 2 can freely retract and retract in the cable clamp channel 3-1.

[0028] When the fastening cable clamp 2 described in this embodiment is connected to the variable diameter outer clamp 4, the threaded connection section 2-3 of the fastening cable clamp 2 extends into the cable clamp connection channel 4-2 of the variable diameter outer clamp 4, and the threaded connection section of the fastening cable clamp 2 is connected to the variable diameter outer clamp 4 through two nuts, and controls the distance between the fastening cable clamp 2 and the variable diameter outer clamp 4.

[0029] In this embodiment, the outer wall of the inner clamp 6 is provided with inner fixing channels 6 - 1 in the circumferential direction, the number of which is equal to the number of the liquid-filled rubber damping elements 5 ; The variable diameter outer clamp is provided with an outer fixing hole 4-1 corresponding to the inner fixing hole 6-1; The liquid-filled rubber damping element 5 is provided with a first groove at one end and a second groove at the other end. When the liquid-filled rubber damping element is injected with pressure liquid, the liquid-filled rubber damping element 5 can expand, the first groove fully bites the inner fixing hole 6-1 on the inner clamp 6, and the second groove fully bites the outer fixing hole 4-1 on the variable diameter outer clamp 4, so as to realize the flexible connection of the two slings. Finally, the outer protective shell is encapsulated.

[0030] As a further preferred embodiment of the present invention, the two ends of the liquid-filled rubber damping element 5 are set to different sizes to adapt to the circumferential arrangement of the liquid-filled rubber damping element in the damper, the larger end of the liquid-filled rubber damping element 5 is engaged with the outer fixed channel 4-1 in the variable diameter outer clamp 4, and the smaller end of the liquid-filled rubber damping element 5 is engaged with the inner fixed channel 6-1 on the inner clamp 6.

[0031] The present invention is applicable to the installation method of the liquid-filled rubber damping vibration isolator for double-cable vibration control of a suspension bridge, comprising the following steps: Step 1: Conduct a thorough on-site investigation, select slings for vibration control or vibration prevention, determine the geometric parameters and dynamic characteristics of the double sling system, and determine the size of the cable clamp; Step 2: Determine the installation height of the liquid-filled rubber damper, install the cable clamp on the double sling, connect the outer protective shell of the shock absorber, and then install the variable diameter outer clamp to control the spacing of the variable diameter outer clamp; Step 3: placing a rubber liquid-filled rubber damping element between the inner clamp and the variable diameter outer clamp, and injecting high-pressure oil into the plurality of rubber liquid-filled rubber damping elements through the self-locking oil injection hole; Step 4: Use a protective shell to cover and seal the inner clamp, the variable diameter outer clamp and the liquid-filled rubber damping element.

[0032] The following points should be noted in the above installation steps: 1. Control the size and center angle of the variable diameter outer clamps to avoid collision between the variable diameter outer clamps; 2. The rubber damping element filled with rubber liquid needs to be lubricated when it is engaged with the outer and inner clamps to prevent the rubber joint from drying out; 3. Clarify the dynamic characteristics of the sling, and the installation height of the damper should not be too high.

[0033] The working method of the liquid-filled rubber damping shock absorber suitable for the vibration control of the double cables of the suspension bridge is to make the dynamic characteristics of the multiple liquid-filled rubber damping elements different by filling different volumes of liquid inside the multiple liquid-filled rubber damping elements, and multiple combinations are used to realize the nonlinear and multi-band vibration control of the damper; Multiple liquid-filled rubber damping elements are arranged along the circumference, and the movement of the sling in each direction can achieve damping energy dissipation, which will simultaneously control the abnormal vibration of the sling in the plane, that is, the span direction, and out of the plane, that is, the vertical span direction; By controlling the liquid pressure inside the liquid-filled rubber damping element, the damping, mass and elasticity of the liquid-filled rubber damping element are controlled, the damping of the sling vibration process is increased, and broadband vibration control of the sling structure is achieved.

[0034] 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 liquid-filled rubber damping shock absorber suitable for vibration control of double suspension cables of a suspension bridge, connected between the two suspension cables, characterized in that: include: The inner clamp is located in the center of the entire shock absorber; A variable diameter outer clamp, located outside the inner clamp; A liquid-filled rubber damping element (5), comprising a plurality of liquid-filled rubber damping elements connected between the inner clamp and the variable-diameter outer clamp, and evenly arranged along the circumference of the inner clamp; A first fastening cable clamp, one end of which is fixedly connected to the first sling located on one side, and the other end of which has a first damper connecting end, wherein the first damper connecting end is connected to a side of the variable diameter outer clamp adjacent to the first sling; A second fastening cable clamp, one end of which is fixedly connected to the second sling located at the other side, and the other end of which has a second damper connecting end, wherein the second damper connecting end is connected to a side of the variable diameter outer clamp adjacent to the second sling; The service performance of the liquid-filled rubber damping element (5) is adjusted by high-pressure hydraulic oil (5-3), and the vibration modal damping ratio targeted by the liquid-filled rubber damping element (5) is controlled to be greater than 0.8%. A plurality of liquid-filled rubber damping elements (5) are combined to control multiple modes, and the in-plane and out-of-plane movements of the double slings are controlled by circumferential arrangement.

2. The liquid-filled rubber damping shock absorber suitable for double-cable vibration control of suspension bridge according to claim 1 is characterized in that: It also includes a protective shell, which covers the inside clamp, the variable diameter outside clamp and the outside of the liquid-filled rubber damping element; A space is reserved between the inner diameter of the protective shell and the variable diameter outer clamp for the variable diameter outer clamp to change its diameter, and the maximum deformation of the variable diameter outer clamp can be restricted; The protective shell is provided with a cable clamp channel for the first damper connecting end and the second damper connecting end to pass through.

3. The liquid-filled rubber damping shock absorber suitable for double-cable vibration control of suspension bridge according to claim 1, characterized in that: The liquid-filled rubber damping element comprises a rubber body, the interior of the rubber body is hollow, a self-locking oil injection hole (5-2) is provided on the rubber body, and hydraulic oil (5-3) is injected into the internal hollow portion through the self-locking oil injection hole (5-2).

4. The liquid-filled rubber damping shock absorber suitable for double-cable vibration control of suspension bridge according to claim 3 is characterized in that: The outer wall of the inner clamp (6) is provided with inner fixing channels (6-1) in the circumferential direction, the number of which is equal to the number of the liquid-filled rubber damping elements (5); An outer fixing hole (4-1) is provided on the variable diameter outer clamp corresponding to the inner fixing hole (6-1); The liquid-filled rubber damping element (5) is provided with a first groove at one end and a second groove at the other end. When pressure liquid is injected into the liquid-filled rubber damping element, the liquid-filled rubber damping element (5) can expand, the first groove fully engages with the inner fixing hole (6-1) on the inner clamp (6), and the second groove fully engages with the outer fixing hole (4-1) on the variable diameter outer clamp (4), thereby realizing a flexible connection between the two slings.

5. The liquid-filled rubber damping shock absorber suitable for double-cable vibration control of suspension bridge according to claim 1, characterized in that: The first fastening cable clip comprises: Two first semi-annular clamps, the two first semi-annular clamps are fixedly connected by a first square clamping plate group and a fastener, and one of the first semi-annular clamps is connected to the first damper connection end; The second fastening cable clip comprises: Two second semi-annular clamps are fixedly connected by a second square clamp plate group and a fastener, and one of the second semi-annular clamps is connected to the second damper connection end.

6. The liquid-filled rubber damping shock absorber suitable for double-cable vibration control of suspension bridge according to claim 5, characterized in that: The variable diameter outer clamp comprises: Two arc-shaped clamps, one of which is threadedly connected to the first damper connecting end, and the other arc-shaped clamp is threadedly connected to the second damper connecting end. The distance between the fastening cable clamp and the variable diameter outer clamp is changed by adjusting the threads to adapt to double sling structures with different spacings.

7. The liquid-filled rubber damping shock absorber suitable for vibration control of double cables of a suspension bridge according to claim 6 is characterized in that: The arc angle of the arc-shaped clamp is less than π to prevent rigid collision between the two clamps.

8. The liquid-filled rubber damping shock absorber suitable for double-cable vibration control of suspension bridge according to claim 1 is characterized in that: The two ends of the liquid-filled rubber damping element (5) are arranged to have different sizes to accommodate the circumferential arrangement of the liquid-filled rubber damping element in the damper; the larger end of the liquid-filled rubber damping element (5) is connected to the variable diameter outer clamp (4), and the smaller end of the liquid-filled rubber damping element (5) is connected to the inner clamp (6).

9. The installation method of the liquid-filled rubber damping shock absorber suitable for double-cable vibration control of a suspension bridge according to claim 1, characterized in that: The steps include: Step 1: Conduct a thorough on-site investigation, select slings for vibration control or vibration prevention, determine the geometric parameters and dynamic characteristics of the double sling system, and determine the size of the cable clamp; Step 2: Determine the installation height of the liquid-filled rubber damper, install the cable clamp on the double sling, connect the outer protective shell of the shock absorber, and then install the variable diameter outer clamp to control the spacing of the variable diameter outer clamp; Step 3: placing a rubber liquid-filled rubber damping element between the inner clamp and the variable diameter outer clamp, and injecting high-pressure oil into the plurality of rubber liquid-filled rubber damping elements through the self-locking oil injection hole; Step 4: Use a protective shell to cover and seal the inner clamp, the variable diameter outer clamp and the liquid-filled rubber damping element.

10. The working method of the liquid-filled rubber damping shock absorber suitable for double-cable vibration control of a suspension bridge according to claim 1, characterized in that: By filling different volumes of liquid into a plurality of liquid-filled rubber damping elements, the dynamic characteristics of the plurality of liquid-filled rubber damping elements are made different, and a variety of combinations are used to achieve nonlinear and multi-band vibration control of the damper; Multiple liquid-filled rubber damping elements are arranged along the circumference, and the movement of the sling in each direction can achieve damping energy dissipation, which will simultaneously control the abnormal vibration of the sling in the plane, that is, the span direction, and out of the plane, that is, the vertical span direction; By controlling the liquid pressure inside the liquid-filled rubber damping element, the damping, mass and elasticity of the liquid-filled rubber damping element are controlled, the damping of the sling vibration process is increased, and broadband vibration control of the sling structure is achieved.

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