Strong nonlinear variable stiffness damping system for controlling vertical bridge direction vortex-induced resonance

Abstract

The invention belongs to the technical field of engineering structure vibration control, and particularly relates to a strong nonlinear variable stiffness damping system for controlling vertical bridge direction vortex-induced resonance, which comprises a bridge tower and a bridge deck slab, and the bridge tower and the bridge deck slab are connected through the strong nonlinear variable stiffness damping system; the strong non-linear variable stiffness damping system comprises a triangular plate, a non-linear spring device and a damper unit are hinged to the end corner of the lower end of the triangular plate, the lower end of the non-linear spring device is hinged to the side face of the bridge tower, and the end, away from the triangular plate, of the damper unit is hinged to the lower side of the bridge deck slab. The end corner, close to the bridge tower, of the upper end of the triangular plate is hinged to the side face of the bridge tower, a connecting rod is hinged to the end corner, close to the bridge deck slab, of the upper end of the triangular plate, and the end, away from the triangular plate, of the connecting rod is hinged to the side face of the bridge deck slab. Vortex-induced resonance of a large-span bridge can be well controlled, and the safety and reliability of the bridge are greatly improved.

Description

Technical Field

[0001] The invention belongs to the technical field of engineering structure vibration control, and in particular relates to a strong nonlinear variable stiffness damping system for controlling vertical bridge vortex-induced resonance. Background Art

[0002] Large-span bridges are prone to generate large vortex-induced vibrations under the action of wind during service, which poses a serious threat to the normal use and safe operation and maintenance of large-span bridges. In order to control vortex-induced vibrations, dampers are usually used. The working principle of dampers is to absorb and dissipate vibration energy by providing damping, thereby reducing the vibration amplitude of the bridge.

[0003] However, traditional dampers have certain bottlenecks in energy consumption and cannot effectively control vortex-induced vibration. In addition, vortex-induced vibration occurs because the frequency of the bridge is close to the environmental excitation frequency, and installing dampers cannot fundamentally reduce the occurrence of vortex-induced vibration. How to fundamentally reduce the occurrence of vortex-induced resonance on the basis of improving the energy consumption of the damper has extremely important engineering application value and theoretical research significance.

[0004] Therefore, in response to the dual needs of increasing the energy efficiency of the damper and reducing vortex-induced resonance, the present invention combines the lever principle and the characteristics of nonlinear variable stiffness to achieve the energy efficiency of the damper to effectively control vibration and dynamically adjust the natural frequency to effectively reduce the occurrence of vortex-induced resonance. Summary of the invention

[0005] The purpose of the present invention is to provide a strong nonlinear variable stiffness damping system for controlling the vortex-induced resonance of a vertical bridge, which can provide a triple vibration reduction control for a long-span bridge, including dynamically adjusting the natural frequency, enhancing damping energy consumption, and limiting the development of large displacements, and can effectively control the vortex-induced resonance of the long-span bridge, thereby greatly improving the safety and reliability of the bridge.

[0006] The technical solution adopted by the present invention is as follows:

[0007] A strong nonlinear variable stiffness damping system for controlling vertical bridge vortex-induced resonance comprises a bridge tower and a bridge deck, wherein the bridge tower and the bridge deck are connected by the strong nonlinear variable stiffness damping system;

[0008] The strong nonlinear variable stiffness damping system includes a triangular plate, a nonlinear spring device and a damper unit are hinged at the end corner of the lower end of the triangular plate, the lower end of the nonlinear spring device is hinged to the side of the bridge tower, the end of the damper unit away from the triangular plate is hinged to the lower side of the bridge deck, the end corner of the upper end of the triangular plate close to the bridge tower is hinged to the side of the bridge tower, the end corner of the upper end of the triangular plate close to the bridge deck is hinged to a connecting rod, and the end of the connecting rod away from the triangular plate is hinged to the side of the bridge deck.

[0009] Furthermore, two first ear plates are fixedly connected to one side of the bridge tower, the side and lower sides of the bridge deck are fixedly connected to second ear plates, the lower end of the nonlinear spring device is hinged to the side of the bridge tower through the first ear plate, the end of the damper unit away from the triangular plate is hinged to the lower side of the bridge deck through the second ear plate, and the end of the connecting rod away from the triangular plate is hinged to the side of the bridge deck through another second ear plate.

[0010] Further, the nonlinear spring device comprises an outer frame, a hollow cavity is formed inside the outer frame, a through hole is formed at one end of the outer frame close to the triangular plate, a special-shaped piston rod is inserted inside the through hole, the special-shaped piston rod can slide in the hollow cavity along the axial direction of the special-shaped piston rod, the special-shaped piston rod is located inside the hollow cavity, and the outer side of the rod body is fixedly connected to two limiting rings, the rod body of the special-shaped piston rod located between the two limiting rings is a guide rod body, the outer side of the guide rod body is sleeved with two baffles, and at least two nonlinear spring bodies are fixedly connected between the two baffles;

[0011] A groove is provided on the inner wall of the hollow cavity, and the two baffles are slidably connected inside the groove, and the length of the groove is smaller than the length of the guide rod body;

[0012] One end of the special-shaped piston rod close to the triangular plate is located on the outside of the outer frame, and the end of the special-shaped piston rod close to the triangular plate is fixedly connected to a connecting ear plate, and the connecting ear plate and the end corner of the lower end of the triangular plate are hinged together, and one end of the outer frame away from the triangular plate is fixedly connected to another connecting ear plate, and the end of the outer frame away from the triangular plate is hinged together with the first ear plate through the connecting ear plate.

[0013] Further, the vertical cross-section of the triangular plate is a right triangle, the short right-angled side of the triangular plate is initially arranged horizontally, the long right-angled side of the triangular plate is initially arranged vertically, and the hypotenuse of the triangular plate is initially opposite to the side of the bridge deck;

[0014] The nonlinear spring device is initially arranged vertically, and the damper unit is initially arranged horizontally.

[0015] The technical effects achieved by the present invention are:

[0016] The strong nonlinear variable stiffness damping system for controlling vertical bridge vortex-induced resonance of the present invention provides a triple vibration reduction control for long-span bridges, including dynamically adjusting the natural frequency, enhancing damping energy consumption, and limiting the development of large displacements. It can well control the vortex-induced resonance of long-span bridges and greatly improve the safety and reliability of bridges. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a plan view schematic diagram of the present invention;

[0018] Figure 2 is a schematic diagram of a nonlinear spring device of the present invention;

[0019] Figure 2 (a) is a cross-sectional view of the nonlinear spring device of the present invention at the initial stage;

[0020] Figure 2 (b) is a cross-sectional view of the nonlinear spring device of the present invention when displacement occurs;

[0021] Figure 2 (c) is a schematic diagram of the conical helical spring under pressure of the present invention;

[0022] Figure 2 (d) is a force displacement curve diagram of a common annular spring and a conical helical spring of the present invention;

[0023] Figure 2 (e) is a stiffness displacement curve diagram of a common annular spring and a conical spiral spring of the present invention;

[0024] Figure 3 The present invention Figure 1 The enlarged view of the initial part at A in the middle;

[0025] Figure 4 The present invention Figure 1 A partial enlarged view of the work at A in the middle;

[0026] Figure 5 It is a stiffness displacement curve diagram of the nonlinear spring device of the present invention.

[0027] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0028] 1. Bridge tower; 2. Bridge deck; 3. Triangle plate; 4. Connecting rod; 5. First ear plate; 6. Nonlinear spring device; 61. Outer frame; 62. Baffle; 63. Nonlinear spring body; 64. Special-shaped piston rod; 65. Bolt; 66. Connecting ear plate; 7. Damper unit; 8. Second ear plate. DETAILED DESCRIPTION

[0029] In order to make the purpose and advantages of the present invention more clearly understood, the present invention is specifically described below in conjunction with embodiments. It should be understood that the following text is only used to describe one or several specific embodiments of the present invention, and does not strictly limit the scope of protection of the specific claims of the present invention.

[0030] like Figure 1-5 As shown, a strong nonlinear variable stiffness damping system for controlling vertical bridge vortex-induced resonance includes a bridge tower 1 and a bridge deck 2. The bridge tower 1 and the bridge deck 2 are connected by the strong nonlinear variable stiffness damping system, so that the bridge tower 1 and the bridge deck 2 form a large-span bridge;

[0031] like Figure 1 and Figure 3-4 As shown, the strong nonlinear variable stiffness damping system comprises a triangular plate 3, a nonlinear spring device 6 and a damper unit 7 are hinged at the end angle of the lower end of the triangular plate 3, the lower end of the nonlinear spring device 6 is hinged to the side of the bridge tower 1 through a first ear plate 5, and the end of the damper unit 7 away from the triangular plate 3 is hinged to the lower side of the bridge deck 2 through a second ear plate 8;

[0032] The upper end of the triangle plate 3 is hinged to the side of the bridge tower 1 through another first ear plate 5 at the end corner near the bridge tower 1, and the upper end of the triangle plate 3 is hinged to the end corner near the bridge deck 2 with a connecting rod 4, and the end of the connecting rod 4 away from the triangle plate 3 is hinged to the side of the bridge deck 2 through another second ear plate 8.

[0033] Specifically, circular holes are provided at the three end corners of the triangular plate 3 for easy hinge connection. The first ear plate 5 at the upper end is connected to the circular hole at the upper end of the triangular plate 3 close to the direction of the bridge tower 1. The connecting rod 4 is connected to the circular hole at the upper end of the triangular plate 3 close to the direction of the bridge deck 2. The upper end of the nonlinear spring device 6 is connected to the circular hole at the lower end of the triangular plate 3.

[0034] At the same time, the two first ear plates 5 are fixedly connected to one side of the bridge tower 1, and the fixing method thereof can be welding or screw connection, and the two second ear plates 8 are respectively fixedly connected to the side and lower sides of the bridge deck 2, and the fixing method of the second ear plates 8 can also be welding or screw connection.

[0035] The nonlinear spring device 6 can dynamically adjust the natural frequency of the long-span bridge through its variable stiffness characteristics, which can effectively reduce the occurrence of resonance; when the amplitude of the vibration displacement is small, the stiffness of the nonlinear spring device 6 is small, and the stroke of the damper unit 7 is guaranteed as much as possible, thereby increasing the energy consumption of the damper unit 7; when the amplitude of the vibration displacement is large, the damper unit 7 plays a full role, and the stiffness of the nonlinear spring device 6 is large, showing a limiting effect.

[0036] Among them, Figure 2-5 As shown, another core of the technical solution is the improvement of the nonlinear spring device 6, which is specifically that the nonlinear spring device 6 includes an outer frame 61, a hollow cavity is opened inside the outer frame 61, a through hole is opened at one end of the outer frame 61 close to the triangular plate 3, a special-shaped piston rod 64 is inserted inside the through hole, the special-shaped piston rod 64 can slide in the hollow cavity along the axial direction of the special-shaped piston rod 64, the special-shaped piston rod 64 is located inside the hollow cavity, and the outer side of the rod body is fixedly connected to two limiting rings, the rod body of the special-shaped piston rod 64 located between the two limiting rings is a guide rod body, and the outer side of the guide rod body is sleeved with two baffles 62, and at least two nonlinear spring bodies 63 are fixedly connected between the two baffles 62;

[0037] like Figure 2 As shown, when the number of the nonlinear spring bodies 63 is two, the two nonlinear spring bodies 63 are symmetrically arranged with the axis of the guide rod body as the center line. When the number of the nonlinear spring bodies 63 is multiple, the multiple nonlinear spring bodies 63 are arranged in a circular array with the axis of the guide rod body as the center of the circle, so that the thrust applied by the nonlinear spring body 63 to the baffle 62 is more uniform.

[0038] At the same time, a groove is provided on the inner wall of the hollow cavity, and two baffles 62 are slidably connected inside the groove. The baffles 62 can only move inside the groove, and the length of the groove is less than the length of the guide rod body. With such a configuration, when the nonlinear spring device 6 is subjected to tension, the special-shaped piston rod 64 is pulled out of the outer frame 61 and extends to the outside of the outer frame 61. The special-shaped piston rod 64 drives the baffle 62 to move, which can convert the tension of the nonlinear spring device 6 into pressure applied to the nonlinear spring body 63. The stiffness of the nonlinear spring body 63 remains unchanged and then increases as the pressure changes. When the special-shaped piston rod 64 of the nonlinear spring device 6 is extended by △L, the nonlinear spring body 63 is in a compressed state and the compression displacement is △L; as the bridge deck 2 undergoes a vertical displacement △Z, the rotation of the triangular plate 3 makes the nonlinear stiffness of the nonlinear spring device 6 more obvious.

[0039] Among them, Figure 2-3 As shown, a bolt 65 is fixedly connected to one end of the outer frame 61 close to the triangular plate 3 and located on the outside of the through hole, and the special-shaped piston rod 64 is slidably connected inside the bolt 65. The bolt 65 can be used to guide the special-shaped piston rod 64 more stably.

[0040] One end of the special-shaped piston rod 64 close to the triangle plate 3 is located on the outside of the outer frame 61, and the end of the special-shaped piston rod 64 close to the triangle plate 3 is fixedly connected to a connecting ear plate 66. The connecting ear plate 66 and the end corner of the lower end of the triangle plate 3 are hinged together. The downward force applied by the triangle plate 3 can be directly applied to the special-shaped piston rod 64 through the connecting ear plate 66.

[0041] One end of the outer frame 61 away from the triangular plate 3 is fixedly connected to another connecting ear plate 66 , and one end of the outer frame 61 away from the triangular plate 3 is hinged to the first ear plate 5 through the connecting ear plate 66 .

[0042] Among them, the nonlinear spring body 63 can be any one of a conical coil spring, a tower spring, an air spring and a variable pitch spring, preferably a conical coil spring, which has a smaller stiffness when initially subjected to force, and ensures the stroke of the damper unit 7 as much as possible, thereby improving the energy consumption of the damper unit 7; as the compressive stroke of the nonlinear spring body 63 increases, the stiffness of the nonlinear spring body 63 is larger, and can exhibit a limiting effect.

[0043] The damper unit 7 may be any one of a viscous damper, a viscoelastic damper, a friction damper and a metal damper, and has high structural safety and good structural durability.

[0044] like Figure 2-3 As shown, the vertical cross-section of the triangle plate 3 is a right triangle, one of the right-angled sides of the triangle plate 3 is a short right-angled side, which is initially horizontally arranged, the other of the triangle plate 3 is a long right-angled side, which is initially vertically arranged, and the hypotenuse of the triangle plate 3 is initially opposite to the side of the bridge deck 2. The sizes of the long and short right-angled sides of the triangle plate 3 can be adjusted according to specific needs.

[0045] In line with the initial structure of the triangular plate 3, the nonlinear spring device 6 is initially arranged vertically, and the damper unit 7 is initially arranged horizontally, so that the relative displacement of the bridge deck 2 can be amplified to both ends of the damper through the triangular plate, thereby achieving the amplification effect of the damper energy consumption.

[0046] The working principle of the present invention is:

[0047] like Figure 2 and Figure 4 As shown, when the bridge deck 2 moves relative to the bridge tower 1, it can be seen that when the vibration displacement amplitude is small, the stiffness of the nonlinear spring device 6 is small, and the stroke of the damper unit 7 is guaranteed as much as possible, thereby increasing the energy consumption of the damper unit 7; when the vibration displacement amplitude is large, the damper unit 7 plays a full role, and the stiffness of the nonlinear spring device 6 is large, showing a limiting effect, limiting the development of large displacement. At the same time, the relative displacement of the bridge deck 3 is amplified by the triangle plate 3 to both ends of the nonlinear spring device 6 and the damper unit 7, and the energy consumption of the damper increases. During the entire vibration process, the stiffness of the nonlinear spring device 6 is not fixed, so that the natural frequency of the long-span bridge changes with the vibration, and the natural frequency is dynamically adjusted, which can effectively reduce the occurrence of resonance.

[0048] In summary, the strong nonlinear variable stiffness damping system in this technical solution provides triple vibration reduction control for long-span bridges: dynamically adjusting the natural frequency, enhancing damping energy consumption, and limiting the development of large displacements. It can effectively control the vortex-induced resonance of large-span bridges and greatly improve the safety and reliability of bridges.

[0049] The above is only a preferred embodiment of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principles of the present invention, and these improvements and modifications should also be considered as the protection scope of the present invention. The structures, devices and operating methods not specifically described and explained in the present invention shall be implemented according to the conventional means in the art unless otherwise specified and limited.

Claims

1. A strong nonlinear variable stiffness damping system for controlling vertical bridge vortex induced resonance, characterized in that: It comprises a bridge tower (1) and a bridge deck (2), wherein the bridge tower (1) and the bridge deck (2) are connected via a strong nonlinear variable stiffness damping system; The strong nonlinear variable stiffness damping system comprises a triangular plate (3), a nonlinear spring device (6) and a damper unit (7) are hinged at the end angle of the lower end of the triangular plate (3), the lower end of the nonlinear spring device (6) is hinged to the side of the bridge tower (1), the end of the damper unit (7) away from the triangular plate (3) is hinged to the lower side of the bridge deck (2), the end angle of the upper end of the triangular plate (3) close to the bridge tower (1) is hinged to the side of the bridge tower (1), the end of the upper end of the triangular plate (3) close to the bridge deck (2) is hinged to a connecting rod (4), and the end of the connecting rod (4) away from the triangular plate (3) is hinged to the side of the bridge deck (2).

2. A strong nonlinear variable stiffness damping system for controlling vertical bridge vortex induced resonance according to claim 1, characterized in that: Two first ear plates (5) are fixedly connected to one side of the bridge tower (1), and second ear plates (8) are fixedly connected to the side and lower side of the bridge deck (2). The lower end of the nonlinear spring device (6) is hinged to the side of the bridge tower (1) through the first ear plate (5), and the end of the damper unit (7) away from the triangular plate (3) is hinged to the lower side of the bridge deck (2) through the second ear plate (8). The end of the connecting rod (4) away from the triangular plate (3) is hinged to the side of the bridge deck (2) through another second ear plate (8).

3. A strong nonlinear variable stiffness damping system for controlling vertical bridge vortex induced resonance according to claim 2, characterized in that: The nonlinear spring device (6) comprises an outer frame (61), a hollow cavity is formed inside the outer frame (61), a through hole is formed at one end of the outer frame (61) close to the triangular plate (3), a special-shaped piston rod (64) is inserted into the through hole, the special-shaped piston rod (64) can slide in the hollow cavity along the axis direction of the special-shaped piston rod (64), the special-shaped piston rod (64) is located inside the hollow cavity and is fixedly connected to two limiting rings on the outside of the rod body, the rod body of the special-shaped piston rod (64) located between the two limiting rings is a guide rod body, the outside of the guide rod body is sleeved with two baffles (62), and at least two nonlinear spring bodies (63) are fixedly connected between the two baffles (62); A groove is provided on the inner wall of the hollow cavity, and the two baffles (62) are slidably connected inside the groove, and the length of the groove is smaller than the length of the guide rod body; The end of the special-shaped piston rod (64) close to the triangular plate (3) is located outside the outer frame (61), and the end of the special-shaped piston rod (64) close to the triangular plate (3) is fixedly connected to a connecting ear plate (66), and the connecting ear plate (66) and the end angle of the lower end of the triangular plate (3) are hinged together, and the end of the outer frame (61) away from the triangular plate (3) is fixedly connected to another connecting ear plate (66), and the end of the outer frame (61) away from the triangular plate (3) is hinged together with the first ear plate (5) through the connecting ear plate (66).

4. A strong nonlinear variable stiffness damping system for controlling vertical bridge vortex induced resonance according to claim 3, characterized in that: When the number of the nonlinear spring bodies (63) is two, the two nonlinear spring bodies (63) are symmetrically arranged with the axis of the guide rod body as the midline; when the number of the nonlinear spring bodies (63) is multiple, the multiple nonlinear spring bodies (63) are arranged in a ring array with the axis of the guide rod body as the center.

5. A strong nonlinear variable stiffness damping system for controlling vertical bridge vortex induced resonance according to claim 3, characterized in that: A bolt (65) is fixedly connected to one end of the outer frame (61) close to the triangular plate (3) and located outside the through hole, and the special-shaped piston rod (64) is slidably connected inside the bolt (65).

6. A strong nonlinear variable stiffness damping system for controlling vertical bridge vortex induced resonance according to claim 3, characterized in that: The nonlinear spring body (63) is any one of a conical helical spring, a conical spring, an air spring and a variable pitch spring.

7. A strong nonlinear variable stiffness damping system for controlling vertical bridge vortex induced resonance according to claim 3, characterized in that: The damper unit (7) is any one of a viscous damper, a viscoelastic damper, a friction damper and a metal damper.

8. A strong nonlinear variable stiffness damping system for controlling vertical bridge vortex induced resonance according to claim 1, characterized in that: The vertical cross-section of the triangular plate (3) is a right triangle, the short right-angled side of the triangular plate (3) is initially arranged horizontally, the long right-angled side of the triangular plate (3) is initially arranged vertically, and the hypotenuse of the triangular plate (3) is initially opposite to the side of the bridge deck (2); The nonlinear spring device (6) is initially arranged vertically, and the damper unit (7) is initially arranged horizontally.

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