斜拉桥气弹模型拉索振动数字摄影测量技术

Vibration Measurement Technique for Cables of Full Aeroelastic Model for CableStayed Bridge Based on Digital Photogrammetry

摘要:

利用数字摄影测量的方法,在斜拉桥全桥气弹模型风洞试验中对拉索结构实现振动位移的动态测量.介绍了该方法的基本原理,并通过某斜拉桥进行了实测研究,获得了该桥气动失稳状态时的拉索振动形态,为桥梁颤振发散机理的研究提供了直接依据.讨论了拉索位移测量方法的误差,并提出改进测量精度的对策.

Abstract:

This paper presents the application of digital photogrammetry in obtaining the vibration response of cables for full aeroelastic cablestayed bridge model in wind tunnel test.In the wind tunnel test,aeroelastic model for a cable stayed bridge with the span of 1 088 m was adopted and the vibration modes for cables during aerodynamic instable status were acquired by image capture and analysis,which clearly revealed the relationship between cable and girder of cable stayed bridge and provided essential data for future research on the mechanism of the flutter of cable stayed bridge with long span.Moreover,the measurement error was discussed and the countermeasures for improving precision were proposed.