Semi-active vibration absorption and energy dissipation control system for restraining bridge vortex-induced vibration of bridge

Abstract

The invention belongs to the technical field of bridge wind-induced vibration control, and provides a semi-active vibration absorption and energy dissipation control system for restraining vortex-induced vibration of a bridge. Compared with a traditional tuned mass damping system, the semi-active vibration absorption and energy dissipation control system has the advantages and characteristics that (1) springs are horizontally placed at the bottom of a beam, and the lengths of the springs are not limited, so that the frequency requirement of a low-frequency target can be met; (2) different target frequencies can be realized through different combinations of the multiple springs connected in series and in parallel, so that the multi-order vortex vibration control requirement is met; (3) the springs made of fiber reinforced nylon materials are adopted, and the springs are slotted, so that the frequency implementation range can be greatly widened; (4) materials and forms of a mass body are not limited, and a water bag can be adopted, so that cost is low, and disassembly, assembly and mass adjustment are convenient; (5) coaxial pulleys with different diameters are adopted, so that the high-frequency vibration control efficiency can be obviously improved; (6) vibration of the mass body is controlled through manual semi-automatic intervention, and higher control efficiency is achieved; (7) the device is small in volume and is mounted at the bottom of the beam without influencing the appearance basically; and (8) the engineering cost is greatly reduced.

Description

technical field [0001] The invention belongs to the technical field of wind-induced vibration control of bridges, and relates to a semi-active vibration-absorbing and energy-dissipating control system for suppressing vortex-induced vibration of bridges. Background technique [0002] Vortex-induced vibration of long-span bridges (referred to as vortex vibration) occurs from time to time, causing adverse effects on the bridge structure itself and the drivers and passengers on the bridge, and even causing social panic, so it is necessary to prevent and control it. Long-span bridges generally experience vertical bending vortex vibration, and torsional vortex vibration rarely occurs. Moreover, even if there is torsional vortex vibration, the amplitude is generally small, and the problem is not serious. Tuned mass dampers can be used to control the vibration of bridges. However, the vertical bending vortex vibration frequency of bridges is low (<0.2Hz, even lower than 0.1Hz). ...

AI Technical Summary

Problems solved by technology

Tuned mass dampers can be used to control the vibration of bridges. However, the vertical bending vortex frequency of bridges is low (<0.2Hz, even lower than 0.1Hz), so the use of tuned mass dampers requires spring stretching or compression lengths of several meters or even dozens m, the lower the frequency, the smaller the corresponding system stiffness, the longer the spring required (squared with the vibration period), the greater the mass, the higher the cost

On the one hand, it is difficult to install directly inside the main girder. On the other hand, if traditional metal springs are used, their mass will be very large, reaching tens of tons or even greater, and their applicability will be greatly reduced.

Therefore, the existing traditional tuned mass dampers are generally only used in occasions where the vibration frequency is higher than 0.2Hz

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