Mass displacement bridge torsional vibration damper

Abstract

The invention discloses a mass shifting type bridge torsional vibration absorber. The mass shifting type bridge torsional vibration absorber mainly comprises a main guide rail horizontally mounted on a bridge base plate, wherein a left guide rail and a right guide rail are symmetrically and movably overlapped at two ends of the main guide rail; the outer side ends of the left guide rail and the right guide rail are fixedly connected with a left baffle and a right baffle respectively; the left guide rail and the left baffle as well as the right guide rail and the right baffle are connected to form right-angle L shapes; the middle bottoms of the left guide rail and the right guide rail are respectively hinged to the bridge base plate through a left hinge support and a right hinge support; a left spring and a right spring are respectively arranged between the bottoms of the outer side ends of the left guide rail and the right guide rail and the bridge base plate; a left vertical column and a right vertical column are further respectively arranged on the bridge base plate at the outer side ends of the left spring and the right spring; grooves with the same shapes are formed in the upper surfaces of the main guide rail, the left guide rail and the right guide rail; a gravity ball is arranged in each groove. With the reduction of the vibration frequency of a bridge, the mass shifting type bridge torsional vibration absorber can supply larger torque to the bridge, so that the vibration absorption effect is better.

Description

technical field [0001] The invention belongs to the technical field of bridge damping, and in particular relates to a mass displacement type bridge torsional vibration damper. Background technique [0002] As the span of the bridge increases, its fundamental frequency becomes smaller and smaller. Under the action of strong winds, bridges will vibrate greatly, endangering the safety of bridges. Among them, the torsion of bridges is the most harmful. Many bridges have collapsed due to torsion. Because, under the action of strong wind, when the bridge undergoes dangerous torsional vibration, that is, bridge flutter, according to the theory of bridge flutter, when the main girder (usually a steel box girder) twists counterclockwise around its centroid, the wind will affect the main girder. There is a counterclockwise torque force (simplified from the main beam surface wind pressure force to the main beam centroid); when the main beam twists clockwise around its centroid, the wi...

AI Technical Summary

Problems solved by technology

The effect of TMD on bridge vibration reduction decreases significantly with the decrease of bridge vibration frequency

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