Pulley-heaving block device for restraining flutter of long-span bridge

Abstract

The invention belongs to the technical field of bridge vibration control, and provides a pulley-heaving block device for inhibiting flutter of a large-span bridge, which is a vibration control system temporarily mounted on the bridge according to flutter control requirements and consists of a heaving block immersed in water, a rope for connecting a pulley block with the heaving block and an anchorage for providing downward tension. When the bridge vibrates upwards, due to the displacement amplification effect of the pulley block, the heaving block moves upwards in water at the speed multiple times that of the bridge, the gravity of the heaving block and the downward water resistance do negative work on the bridge, and vibration energy is consumed; when the bridge vibrates downwards, the heaving block and the bridge move approximately synchronously by optimizing design parameters, and large-amplitude flutter of the bridge is efficiently restrained. The reinforced concrete heaving block is more economical compared with a metal heaving plate, and due to the introduction of the pulley block, the total resistance borne by the bridge is multiple times of the gravity of the heaving block and the water resistance, so that the control efficiency is higher. The pulley-heaving block device has the advantages of being convenient to disassemble and assemble, economical, practical, safe and efficient.

Description

technical field [0001] The invention belongs to the technical field of bridge wind-induced vibration control research, and relates to a pulley-heave block device for suppressing flutter of long-span bridges. Background technique [0002] In the past 20 years, great achievements have been made in the construction of long-span bridges at home and abroad. The modern long-span bridges mainly represented by cable-stayed bridges and suspension bridges continue to develop in the direction of larger spans, and the structural stiffness and damping are reduced accordingly. It is more sensitive, and the problem of bridge wind resistance is more prominent. Wind-induced large-scale limit cycle vibration and divergent flutter of long-span bridges need to be eliminated. Traditional measures for flutter control of long-span bridges mainly include aerodynamic measures, structural measures and mechanical measures. Aiming at some deficiencies in traditional flutter control measures, the inve...

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Problems solved by technology

[0003] The technical problem to be solved by the present invention is to propose a pulley-heave block device for suppressing the chatter of long-span bridges to meet the needs of flutter control of long-span bridges such as crossing seas and rivers. The upward movement displacement and velocity of the heave block under the bridge and submerged in the water increase the water resistance of the heave block and the work range of the gravity and water resistance of the heave block, making it consume more energy. When the bridge moves downward When the heave block is affected by gravity, buoyancy and water resistance, by optimizing the density, size, shape and other parameters of the heave block, it can be as close as possible to the downward movement of the bridge and reduce the energy input to the bridge vibration. When the bridge moves upwards in one cycle, the heave blocks play an energy-dissipating role again, repeating the cycle, and finally greatly improve the critical wind speed of flutter and the safety of wind resistance, and effectively suppress the vibration of the bridge structure

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