SEMI-ACTIVE VIBRATION ABSORPTION AND ENERGY DISSIPATION CONTROL SYSTEM FOR RESTRAINING VORTEX-INDUCED VIBRATION OF BRIDGES

Abstract

The present invention provides a semi-active vibration absorption and energy dissipation control system for restraining vortex-induced vibration of bridges. It has the advantages and characteristics that: (1) springs are horizontally placed at the bottom of a beam, and lengths are not limited, so that the frequency requirement of a low-frequency target can be satisfied; (2) different target frequencies can be realized through different combinations of a plurality of springs connected in series and in parallel, so that multi-order vortex-induced vibration control needs are satisfied; (3) the springs made of fiber reinforced nylon materials are adopted, and are notched, so that a frequency implementation range can be greatly widened; (4) the material and the form of a mass body are not limited, and a water bag can be used, which has low cost and is convenient for disassembly, assembly and mass adjustment.

Claims

1. A semi-active vibration absorption and energy dissipation control system for restraining vortex-induced vibration of bridges, comprising a spring end plate fixed on a bottom plate of a main beam, a linear tensile spring, a vertical suspension rope, a slider, a slideway, a first high-strength rope, a first pulley, a second pulley, a second high-strength rope, a mass body, a pulley fixing device, an energy dissipation device, an electric control jack and a controller, wherein the spring end plate is fixed on the bottom plate of the main beam and used to fix a starting end of the horizontally arranged linear tensile spring; the upper end of the vertical suspension rope and the slider are connected, and arranged at intervals to provide vertical suspension points for the linear tensile spring; the slider is embedded in the slideway fixed on the bottom plate of the main beam; one end of the first high-strength rope is connected with the end of the linear tensile spring, and the other end is fixed and wound on the first pulley; the first pulley is coaxially fixed with the second pulley, and the diameter of the second pulley is larger than the diameter of the first pulley; the upper end of the second high-strength rope is fixed and wound on the second pulley, and the lower end is connected with the mass body; the first pulley and the second pulley are supported below the bottom plate of the main beam by the pulley fixing device; the energy dissipation device is connected with the electric control jack which is fixed below the bottom plate of the main beam; the controller is used to control the electric control jack so as to drive the energy dissipation device; the mass of the linear tensile spring, the stiffness of the linear tensile spring, the mass of the mass body and the diameter ratio of the first pulley and the second pulley are adjusted to make the vibration frequency of the semi-active vibration absorption and energy dissipation control system close to the vibration frequency of a bridge; the principle of resonance energy absorption is used to transfer the vibration energy of the bridge to the semi-active vibration absorption and energy dissipation control system, and the friction between the energy dissipation device and the second pulley is used to dissipate the total energy of the semi-active vibration absorption and energy dissipation control system to suppress the vibration of the bridge.

2. The semi-active vibration absorption and energy dissipation control system for restraining vortex-induced vibration of bridges according to claim 1, wherein the sag effect and nonlinear effect of the linear tensile spring are reduced or eliminated by using the vertical suspension rope, the slider (4) and the slideway, and the linear tensile spring is placed in a horizontally placed pipeline, groove or plate or sleeved on a horizontally placed pipe rod for replacement.

3. The semi-active vibration absorption and energy dissipation control system for restraining vortex-induced vibration of bridges according to claim 1, wherein the linear tensile spring is horizontally placed on the bottom plate of the main beam, and the length is not limited, and also not limited to the internal space of the main beam; the linear tensile spring is made of fiber reinforced nylon material and is opened or grooved, to reduce the amount of the material.

4. The semi-active vibration absorption and energy dissipation control system for restraining vortex-induced vibration of bridges according to claim 1, wherein two sets of semi-active vibration absorption and energy dissipation control systems are symmetrically arranged to reduce the weight of a single set of semi-active vibration absorption and energy dissipation control system, eliminate the horizontal force of the spring end plate and the pulley fixing device, and improve the stress of the bridge.

5. The semi-active vibration absorption and energy dissipation control system for restraining vortex-induced vibration of bridges according to claim 3, wherein two sets of semi-active vibration absorption and energy dissipation control systems are symmetrically arranged to reduce the weight of a single set of semi-active vibration absorption and energy dissipation control system, eliminate the horizontal force of the spring end plate and the pulley fixing device, and improve the stress of the bridge.

6. The semi-active vibration absorption and energy dissipation control system for restraining vortex-induced vibration of bridges according to claim 1, wherein the linear tensile spring is a full-length spring, or arranged in sections in series or in parallel.

7. The semi-active vibration absorption and energy dissipation control system for restraining vortex-induced vibration of bridges according to claim 3, wherein the linear tensile spring is a full-length spring, or arranged in sections in series or in parallel.

8. The semi-active vibration absorption and energy dissipation control system for restraining vortex-induced vibration of bridges according to claim 4, wherein the linear tensile spring is a full-length spring, or arranged in sections in series or in parallel.

9. The semi-active vibration absorption and energy dissipation control system for restraining vortex-induced vibration of bridges according to claim 1, wherein the mass body is a steel plate, a steel block, a lead block, a concrete block or a water bag.

10. The semi-active vibration absorption and energy dissipation control system for restraining vortex-induced vibration of bridges according to claim 6, wherein the mass body is a steel plate, a steel block, a lead block, a concrete block or a water bag.

Description

DESCRIPTION OF DRAWINGS

[0025] FIG. 1 is a structural diagram of a semi-active vibration absorption and energy dissipation control system for restraining vortex-induced vibration of long-span bridges.

[0026] FIG. 2 is a locally enlarged view of an energy dissipation device of a pulley in FIG. 1.

[0027] In the drawings: 1 spring end plate; 2 linear tensile spring; 3 vertical suspension rope; 4 slider; 5 slideway; 6 first high-strength rope; 7 first pulley; 8 second pulley; 9 second high-strength rope; 10 mass body; 11 pulley fixing device; 12 energy dissipation device; 13 electric control jack; 14 controller.

DETAILED DESCRIPTION

[0028] Specific embodiments of the present invention are described below in detail in combination with the technical solution and accompanying drawings, but the implementation of the present invention is not limited to this.

[0029] As shown in FIG. 1, a semi-active vibration absorption and energy dissipation control system for restraining vortex-induced vibration of long-span bridges comprises a spring end plate 1 fixed on a bottom plate of the main beam, a linear tensile spring 2, a vertical suspension rope 3, a slider 4, a slideway 5, a first high-strength rope 6, a first pulley 7, a second pulley 8, a second high-strength rope 9, a mass body 10, a pulley fixing device 11, an energy dissipation device 12, an electric control jack 13 and a controller 14. The spring end plate 1 is generally arranged on the bottom of the main beam or a pier (tower and abutment), can be made of stiffener steel plates and is used to fix one or a plurality of horizontally arranged linear tensile springs 2 connected in series or in parallel. The original length and tensile length of the linear tensile spring 2 are generally long. A plurality of vertical suspension ropes 3 can be arranged at intervals to provide vertical suspension points to reduce the nonlinear effect caused by the sag. The upper end of the vertical suspension rope 3 and the slider 4 are connected; the slider 4 is embedded in the slideway 5 fixed on the bottom plate of the main beam; One end of the first high-strength rope 6 is connected with the end of the linear tensile spring 2, and the other end is fixed and wound on the first pulley 7; and the winding length is ensured to be enough to satisfy the expansion and contraction needs of the linear tensile spring 2.The first pulley 7 is coaxially fixed with the second pulley 8 with a larger diameter; the upper end of the second high-strength rope 9 is fixed and wound on the second pulley 8, and the winding length is ensured to be enough; and the lower end of the second high-strength rope 9 is connected with the mass body 10; the first pulley 7 and the second pulley 8 are supported below the main beam by the fixing device 11; The energy dissipation device 12 is connected with the electric control jack 13, and controlled by movement and states. The controller 14 is used to control the electric control jack 13 so as to drive the energy dissipation device 12. When the speed of the mass body 10 is basically close to zero, the second pulley 8 is clamped and then relaxed. The kinetic energy and the potential energy of the mass body 10 can be rapidly consumed by friction. Energy consumption can also be generated through the friction between energy dissipation device 12 and the second pulley 8 in the vibration process of the mass body 10. The stiffness of the linear tensile spring 2, the mass of the mass body 10 and the diameter ratio of the first pulley 7 and the second pulley 8 are set according to the vibration frequency of the bridge to make the vibration frequency of the control system close to the vibration frequency of the bridge; the principle of resonance energy absorption is used to transfer the vibration energy of the bridge to the semi-active vibration absorption and energy dissipation control system, and the friction between the energy dissipation device 12 and the second pulley 8 is used to dissipate the total energy of the semi-active vibration absorption and energy dissipation control system to suppress the vibration of the bridge. If two sets of the devices are arranged symmetrically left and right, the weight of a single set of mass body 10 can be reduced, and the specification of the linear tensile spring 2 is adjusted accordingly. The horizontal tension of a single spring end plate 1 can also be reduced. The horizontal force of the pulley fixing device 11 can also be offset and the local stress of the main beam can be improved. For the working condition of high frequency, when the tensile length of the spring is short, two sets of the devices can be made symmetrically left and right, and installed symmetrically in a frame fixed at the bottom of the main beam, thereby improving the structural stress.

[0030] The semi-active vibration absorption and energy dissipation control system for restraining vortex-induced vibration of bridges provided by the present invention can conveniently adjust the system parameters to realize the control requirements of multi-order vertical bending vortex-induced vibration. The reasonably arranged semi-active vibration absorption and energy dissipation control system can also control the torsional vortex-induced vibration of the bridges, restrain the flutter of some bridges, increase the critical wind speed of flutter and reduce the amplitude. Through the appropriate transformation of the device, the control system can also be applied to vortex-induced vibration, flutter, and galloping control of other structures, and has wide application scope, convenience, rapidness, safety and, practicality.

[0031] The above only describes preferred embodiments of the present invention and is not intended to limit the present invention in any form. Any equivalent change, modification, or evolution made to the above embodiments by those skilled in the art through the technical solutions of the present invention shall still belong to the scope of the technical solutions of the present invention.