Analysis of Rain-Wind Induced Cable Vibration Using Spatially Measured Aerodynamic Coefficients: Fid-Bau Portal

Analysis of Rain-Wind Induced Cable Vibration Using Spatially Measured Aerodynamic Coefficients

Li, Yongle / Xu, Y.L. / Xiang, Huoyue / Chen, Bo / Shum, K.M. / Liao, Haili

In most currently-used analytical models for studying rain-wind induced cable vibration, wind velocity relative to cable motion was determined by trigonometric decomposition and the aerodynamic coefficients of a cable were measured through wind tunnel tests using a horizontal cable model with two-dimensional flow field. In this paper, the aerodynamic coefficients of a cable were measured using a spatial cable model with a three-dimensional flow and an analytical model was developed to predict rain-wind induced cable vibration. The feasibility of the proposed analytical model was examined through the comparison with wind tunnel test results. The mechanism of rain-wind induced cable vibration was also investigated from viewpoints of rivulet motion and system energy. Further, an extensive parametric study was carried out in this study to investigate the properties of rain-wind induced vibration of a stay cable. The observation indicates that rain-wind induced cable vibration is essentially similar to cable galloping with limited amplitude, which is mainly induced by negative slope of lift coefficient curve and rivulet oscillation. The results from the parametric study indicate that the aerodynamic and motion parameters of cables may affect the maximum amplitude and the wind speed range for the occurrence of rain-wind induced vibration.