Initial condition and damping effects on rain−wind induced cable vibration

Abstract

Rain−wind induced cable vibration (RWIV) has become a worldwide concern in bridge engineering and wind engineering in recent decades. Extensive research has been conducted with the aim of revealing the excitation mechanism of RWIV and suppressing this large vibration. Recently, the excitation mechanism of RWIV has been explained as the interaction between the upper rivulet, the air boundary layer, and the cable vibration, indicating that the initial condition and the structural damping might have significant effects on RWIV. However, experimental investigations of the initial condition and damping ratio effects are relatively rare. In this study, RWIV of a model cable is reproduced in an open-jet wind tunnel. The displacement of RWIV is measured when the model cable has different damping ratios and initial vibration amplitudes. The effects of the damping ratios and initial vibration amplitudes on RWIV are investigated and evaluated through the aerodynamic damping ratio induced by the upper rivulet and the wind flow. Finally, a critical damping ratio for RWIV suppression is estimated based on the statistical analysis results.